Merge "Merge remote-tracking branch 'origin/dev' into wip/scenegraphng"wip/scenegraphng

234 files changed, 5712 insertions, 3284 deletions

diff --git a/.gitignore b/.gitignore
index 57606bfacf..9905dd1fdc 100644
--- a/.gitignore
+++ b/.gitignore
@@ -32,6 +32,7 @@ wrapper.bat
 *.*#
 core
 .qmake.cache
+.qmake.stash
 .qmake.vars
 *.prl
 tags
diff --git a/src/3rdparty/masm/assembler/ARM64Assembler.h b/src/3rdparty/masm/assembler/ARM64Assembler.h
index a9166e83a2..ca6b33d39a 100644
--- a/src/3rdparty/masm/assembler/ARM64Assembler.h
+++ b/src/3rdparty/masm/assembler/ARM64Assembler.h
@@ -26,7 +26,7 @@
 #ifndef ARM64Assembler_h
 #define ARM64Assembler_h
 
-#if ENABLE(ASSEMBLER) && (CPU(ARM64) || defined(V4_BOOTSTRAP))
+#if ENABLE(ASSEMBLER) && CPU(ARM64)
 
 #include "AssemblerBuffer.h"
 #include "AbstractMacroAssembler.h"
@@ -3021,10 +3021,7 @@ public:
 
     static void cacheFlush(void* code, size_t size)
     {
-#if defined(V4_BOOTSTRAP)
-        UNUSED_PARAM(code)
-        UNUSED_PARAM(size)
-#elif OS(IOS)
+#if OS(IOS)
         sys_cache_control(kCacheFunctionPrepareForExecution, code, size);
 #elif OS(LINUX)
         size_t page = pageSize();
diff --git a/src/3rdparty/masm/assembler/ARMv7Assembler.h b/src/3rdparty/masm/assembler/ARMv7Assembler.h
index d57e5a7c78..f2e8dc1a1b 100644
--- a/src/3rdparty/masm/assembler/ARMv7Assembler.h
+++ b/src/3rdparty/masm/assembler/ARMv7Assembler.h
@@ -27,7 +27,7 @@
 #ifndef ARMAssembler_h
 #define ARMAssembler_h
 
-#if ENABLE(ASSEMBLER) && (CPU(ARM_THUMB2) || defined(V4_BOOTSTRAP))
+#if ENABLE(ASSEMBLER) && CPU(ARM_THUMB2)
 
 #include "AssemblerBuffer.h"
 #include "MacroAssemblerCodeRef.h"
@@ -2166,7 +2166,6 @@ public:
         linkJumpAbsolute(location, to);
     }
 
-#if !defined(V4_BOOTSTRAP)
     static void linkCall(void* code, AssemblerLabel from, void* to)
     {
         ASSERT(!(reinterpret_cast<intptr_t>(code) & 1));
@@ -2175,14 +2174,12 @@ public:
 
         setPointer(reinterpret_cast<uint16_t*>(reinterpret_cast<intptr_t>(code) + from.m_offset) - 1, to, false);
     }
-#endif
 
     static void linkPointer(void* code, AssemblerLabel where, void* value)
     {
         setPointer(reinterpret_cast<char*>(code) + where.m_offset, value, false);
     }
 
-#if !defined(V4_BOOTSTRAP)
     static void relinkJump(void* from, void* to)
     {
         ASSERT(!(reinterpret_cast<intptr_t>(from) & 1));
@@ -2205,7 +2202,6 @@ public:
     {
         return readPointer(reinterpret_cast<uint16_t*>(from) - 1);
     }
-#endif
 
     static void repatchInt32(void* where, int32_t value)
     {
@@ -2234,7 +2230,6 @@ public:
         cacheFlush(location, sizeof(uint16_t) * 2);
     }
 
-#if !defined(V4_BOOTSTRAP)
     static void repatchPointer(void* where, void* value)
     {
         ASSERT(!(reinterpret_cast<intptr_t>(where) & 1));
@@ -2246,7 +2241,6 @@ public:
     {
         return reinterpret_cast<void*>(readInt32(where));
     }
-#endif
 
     static void replaceWithJump(void* instructionStart, void* to)
     {
@@ -2321,7 +2315,7 @@ public:
 
     unsigned debugOffset() { return m_formatter.debugOffset(); }
 
-#if OS(LINUX) && !defined(V4_BOOTSTRAP)
+#if OS(LINUX)
     static inline void linuxPageFlush(uintptr_t begin, uintptr_t end)
     {
         asm volatile(
@@ -2341,10 +2335,7 @@ public:
 
     static void cacheFlush(void* code, size_t size)
     {
-#if defined(V4_BOOTSTRAP)
-        UNUSED_PARAM(code)
-        UNUSED_PARAM(size)
-#elif OS(IOS)
+#if OS(IOS)
         sys_cache_control(kCacheFunctionPrepareForExecution, code, size);
 #elif OS(LINUX)
         size_t page = pageSize();
@@ -2662,11 +2653,6 @@ private:
     
     static void linkBX(uint16_t* instruction, void* target)
     {
-#if defined(V4_BOOTSTRAP)
-        UNUSED_PARAM(instruction);
-        UNUSED_PARAM(target);
-        RELEASE_ASSERT_NOT_REACHED();
-#else
         // FIMXE: this should be up in the MacroAssembler layer. :-(
         ASSERT(!(reinterpret_cast<intptr_t>(instruction) & 1));
         ASSERT(!(reinterpret_cast<intptr_t>(target) & 1));
@@ -2679,7 +2665,6 @@ private:
         instruction[-3] = twoWordOp5i6Imm4Reg4EncodedImmFirst(OP_MOVT, hi16);
         instruction[-2] = twoWordOp5i6Imm4Reg4EncodedImmSecond(JUMP_TEMPORARY_REGISTER, hi16);
         instruction[-1] = OP_BX | (JUMP_TEMPORARY_REGISTER << 3);
-#endif
     }
     
     void linkConditionalBX(Condition cond, uint16_t* instruction, void* target)
@@ -2712,9 +2697,6 @@ private:
             instruction[-3] = OP_NOP_T2b;
             linkJumpT4(instruction, target);
         } else {
-#if defined(V4_BOOTSTRAP)
-            RELEASE_ASSERT_NOT_REACHED();
-#else
             const uint16_t JUMP_TEMPORARY_REGISTER = ARMRegisters::ip;
             ARMThumbImmediate lo16 = ARMThumbImmediate::makeUInt16(static_cast<uint16_t>(reinterpret_cast<uint32_t>(target) + 1));
             ARMThumbImmediate hi16 = ARMThumbImmediate::makeUInt16(static_cast<uint16_t>(reinterpret_cast<uint32_t>(target) >> 16));
@@ -2723,7 +2705,6 @@ private:
             instruction[-3] = twoWordOp5i6Imm4Reg4EncodedImmFirst(OP_MOVT, hi16);
             instruction[-2] = twoWordOp5i6Imm4Reg4EncodedImmSecond(JUMP_TEMPORARY_REGISTER, hi16);
             instruction[-1] = OP_BX | (JUMP_TEMPORARY_REGISTER << 3);
-#endif
         }
     }
     
diff --git a/src/3rdparty/masm/assembler/AbstractMacroAssembler.h b/src/3rdparty/masm/assembler/AbstractMacroAssembler.h
index d0c1c4613e..14644a4193 100644
--- a/src/3rdparty/masm/assembler/AbstractMacroAssembler.h
+++ b/src/3rdparty/masm/assembler/AbstractMacroAssembler.h
@@ -66,7 +66,7 @@ public:
     typedef MacroAssemblerCodePtr CodePtr;
     typedef MacroAssemblerCodeRef CodeRef;
 
-#if !CPU(ARM_THUMB2) && !CPU(ARM64) && !defined(V4_BOOTSTRAP)
+#if !CPU(ARM_THUMB2) && !CPU(ARM64)
     class Jump;
 #endif
 
@@ -328,7 +328,7 @@ public:
         friend class AbstractMacroAssembler;
         friend struct DFG::OSRExit;
 
-#if CPU(ARM_THUMB2) || CPU(ARM64) || defined(V4_BOOTSTRAP)
+#if CPU(ARM_THUMB2) || CPU(ARM64)
         using Jump = typename AssemblerType::template Jump<Label>;
         friend Jump;
 #else
@@ -461,7 +461,7 @@ public:
         AssemblerLabel m_label;
     };
 
-#if CPU(ARM_THUMB2) || CPU(ARM64) || defined(V4_BOOTSTRAP)
+#if CPU(ARM_THUMB2) || CPU(ARM64)
     using Jump = typename AssemblerType::template Jump<Label>;
     friend Jump;
 #endif
@@ -516,7 +516,7 @@ public:
     // into the code buffer - it is typically used to link the jump, setting the
     // relative offset such that when executed it will jump to the desired
     // destination.
-#if !CPU(ARM_THUMB2) && !CPU(ARM64) && !defined(V4_BOOTSTRAP)
+#if !CPU(ARM_THUMB2) && !CPU(ARM64)
     class Jump {
         template<class TemplateAssemblerType>
         friend class AbstractMacroAssembler;
@@ -528,7 +528,7 @@ public:
         {
         }
         
-#if CPU(ARM_THUMB2) || defined(V4_BOOTSTRAP)
+#if CPU(ARM_THUMB2)
         // Fixme: this information should be stored in the instruction stream, not in the Jump object.
         Jump(AssemblerLabel jmp, ARMv7Assembler::JumpType type = ARMv7Assembler::JumpNoCondition, ARMv7Assembler::Condition condition = ARMv7Assembler::ConditionInvalid)
             : m_label(jmp)
@@ -621,7 +621,7 @@ public:
 
     private:
         AssemblerLabel m_label;
-#if CPU(ARM_THUMB2) || defined(V4_BOOTSTRAP)
+#if CPU(ARM_THUMB2)
         ARMv7Assembler::JumpType m_type;
         ARMv7Assembler::Condition m_condition;
 #endif
@@ -878,12 +878,10 @@ protected:
         AssemblerType::repatchPointer(dataLabelPtr.dataLocation(), value);
     }
     
-#if !defined(V4_BOOTSTRAP)
     static void* readPointer(CodeLocationDataLabelPtr dataLabelPtr)
     {
         return AssemblerType::readPointer(dataLabelPtr.dataLocation());
     }
-#endif
     
     static void replaceWithLoad(CodeLocationConvertibleLoad label)
     {
diff --git a/src/3rdparty/masm/assembler/LinkBuffer.h b/src/3rdparty/masm/assembler/LinkBuffer.h
index a1bb046d43..8e9a3d9c7a 100644
--- a/src/3rdparty/masm/assembler/LinkBuffer.h
+++ b/src/3rdparty/masm/assembler/LinkBuffer.h
@@ -374,7 +374,7 @@ public:
     }
 };
 
-#if CPU(ARM_THUMB2) || CPU(ARM64) || defined(V4_BOOTSTRAP)
+#if CPU(ARM_THUMB2) || CPU(ARM64)
 
 template <typename T>
 struct BranchCompactingExecutableOffsetCalculator {
@@ -509,7 +509,7 @@ inline void BranchCompactingLinkBuffer<MacroAssembler>::linkCode(void* ownerUID,
     m_executableMemory->shrink(m_size);
 }
 
-#if CPU(ARM_THUMB2) || defined(V4_BOOTSTRAP)
+#if CPU(ARM_THUMB2)
 template <>
 class LinkBuffer<JSC::MacroAssembler<MacroAssemblerARMv7>> : public BranchCompactingLinkBuffer<JSC::MacroAssembler<MacroAssemblerARMv7>>
 {
@@ -520,7 +520,7 @@ public:
 };
 #endif
 
-#if CPU(ARM64) || defined(V4_BOOTSTRAP)
+#if CPU(ARM64)
 template <>
 class LinkBuffer<JSC::MacroAssembler<MacroAssemblerARM64>> : public BranchCompactingLinkBuffer<JSC::MacroAssembler<MacroAssemblerARM64>>
 {
diff --git a/src/3rdparty/masm/assembler/MacroAssembler.h b/src/3rdparty/masm/assembler/MacroAssembler.h
index b442a81bd0..aada47303f 100644
--- a/src/3rdparty/masm/assembler/MacroAssembler.h
+++ b/src/3rdparty/masm/assembler/MacroAssembler.h
@@ -97,10 +97,7 @@ public:
     using MacroAssemblerBase::load32;
 
 
-#if defined(V4_BOOTSTRAP)
-    using MacroAssemblerBase::loadPtr;
-    using MacroAssemblerBase::storePtr;
-#elif CPU(X86_64) || CPU(ARM64)
+#if CPU(X86_64) || CPU(ARM64)
     using MacroAssemblerBase::add64;
     using MacroAssemblerBase::sub64;
     using MacroAssemblerBase::xor64;
@@ -214,14 +211,12 @@ public:
         store32(value, addressForPoke(index));
     }
 
-#if !defined(V4_BOOTSTRAP)
     void poke(TrustedImmPtr imm, int index = 0)
     {
         storePtr(imm, addressForPoke(index));
     }
-#endif
 
-#if (CPU(X86_64) || CPU(ARM64)) && !defined(V4_BOOTSTRAP)
+#if CPU(X86_64) || CPU(ARM64)
     void peek64(RegisterID dest, int index = 0)
     {
         load64(Address(MacroAssemblerBase::stackPointerRegister, (index * sizeof(void*))), dest);
@@ -352,7 +347,6 @@ public:
         return !(this->random() & (BlindingModulus - 1));
     }
 
-#if !defined(V4_BOOTSTRAP)
     // Ptr methods
     // On 32-bit platforms (i.e. x86), these methods directly map onto their 32-bit equivalents.
     // FIXME: should this use a test for 32-bitness instead of this specific exception?
@@ -877,7 +871,7 @@ public:
     {
         return branchSub64(cond, src1, src2, dest);
     }
-#endif // !defined(V4_BOOTSTRAP)
+#endif // !CPU(X86_64) && !CPU(ARM64)
 
 #if ENABLE(JIT_CONSTANT_BLINDING)
     using MacroAssemblerBase::and64;
@@ -1101,8 +1095,6 @@ public:
 
 #endif
 
-#endif // !CPU(X86_64)
-
 #if ENABLE(JIT_CONSTANT_BLINDING)
     bool shouldBlind(Imm32 imm)
     {
diff --git a/src/3rdparty/masm/assembler/MacroAssemblerARM64.h b/src/3rdparty/masm/assembler/MacroAssemblerARM64.h
index 3e6dfcf635..c0c68f6393 100644
--- a/src/3rdparty/masm/assembler/MacroAssemblerARM64.h
+++ b/src/3rdparty/masm/assembler/MacroAssemblerARM64.h
@@ -26,7 +26,7 @@
 #ifndef MacroAssemblerARM64_h
 #define MacroAssemblerARM64_h
 
-#if ENABLE(ASSEMBLER) && (CPU(ARM64) || defined(V4_BOOTSTRAP))
+#if ENABLE(ASSEMBLER) && CPU(ARM64)
 
 #include "ARM64Assembler.h"
 #include "AbstractMacroAssembler.h"
@@ -211,33 +211,6 @@ public:
     static bool shouldBlindForSpecificArch(uint32_t value) { return value >= 0x00ffffff; }
     static bool shouldBlindForSpecificArch(uint64_t value) { return value >= 0x00ffffff; }
 
-#if defined(V4_BOOTSTRAP)
-    void loadPtr(ImplicitAddress address, RegisterID dest)
-    {
-        load64(address, dest);
-    }
-
-    void subPtr(TrustedImm32 imm, RegisterID dest)
-    {
-        sub64(imm, dest);
-    }
-
-    void addPtr(TrustedImm32 imm, RegisterID dest)
-    {
-        add64(imm, dest);
-    }
-
-    void addPtr(TrustedImm32 imm, RegisterID src, RegisterID dest)
-    {
-        add64(imm, src, dest);
-    }
-
-    void storePtr(RegisterID src, ImplicitAddress address)
-    {
-        store64(src, address);
-    }
-#endif
-
     // Integer operations:
 
     void add32(RegisterID a, RegisterID b, RegisterID dest)
@@ -2822,7 +2795,6 @@ public:
         return branch32(cond, left, dataTempRegister);
     }
 
-#if !defined(V4_BOOTSTRAP)
     PatchableJump patchableBranchPtr(RelationalCondition cond, Address left, TrustedImmPtr right)
     {
         m_makeJumpPatchable = true;
@@ -2830,7 +2802,6 @@ public:
         m_makeJumpPatchable = false;
         return PatchableJump(result);
     }
-#endif
 
     PatchableJump patchableBranchTest32(ResultCondition cond, RegisterID reg, TrustedImm32 mask = TrustedImm32(-1))
     {
diff --git a/src/3rdparty/masm/assembler/MacroAssemblerARMv7.h b/src/3rdparty/masm/assembler/MacroAssemblerARMv7.h
index 99801a0e3b..6232834fde 100644
--- a/src/3rdparty/masm/assembler/MacroAssemblerARMv7.h
+++ b/src/3rdparty/masm/assembler/MacroAssemblerARMv7.h
@@ -27,7 +27,7 @@
 #ifndef MacroAssemblerARMv7_h
 #define MacroAssemblerARMv7_h
 
-#if ENABLE(ASSEMBLER) && (CPU(ARM_THUMB2) || defined(V4_BOOTSTRAP))
+#if ENABLE(ASSEMBLER) && CPU(ARM_THUMB2)
 
 #include "ARMv7Assembler.h"
 #include "AbstractMacroAssembler.h"
@@ -162,41 +162,12 @@ public:
     {
         add32(imm, dest, dest);
     }
-
-#if defined(V4_BOOTSTRAP)
-    void loadPtr(ImplicitAddress address, RegisterID dest)
-    {
-        load32(address, dest);
-    }
-
-    void subPtr(TrustedImm32 imm, RegisterID dest)
-    {
-        sub32(imm, dest);
-    }
-
-    void addPtr(TrustedImm32 imm, RegisterID dest)
-    {
-        add32(imm, dest);
-    }
-
-    void addPtr(TrustedImm32 imm, RegisterID src, RegisterID dest)
-    {
-        add32(imm, src, dest);
-    }
-
-    void storePtr(RegisterID src, ImplicitAddress address)
-    {
-        store32(src, address);
-    }
-#endif
     
-#if !defined(V4_BOOTSTRAP)
     void add32(AbsoluteAddress src, RegisterID dest)
     {
         load32(src.m_ptr, dataTempRegister);
         add32(dataTempRegister, dest);
     }
-#endif
 
     void add32(TrustedImm32 imm, RegisterID src, RegisterID dest)
     {
@@ -237,7 +208,6 @@ public:
         add32(dataTempRegister, dest);
     }
 
-#if !defined(V4_BOOTSTRAP)
     void add32(TrustedImm32 imm, AbsoluteAddress address)
     {
         load32(address.m_ptr, dataTempRegister);
@@ -282,7 +252,6 @@ public:
         m_assembler.adc(dataTempRegister, dataTempRegister, ARMThumbImmediate::makeEncodedImm(imm.m_value >> 31));
         m_assembler.str(dataTempRegister, addressTempRegister, ARMThumbImmediate::makeUInt12(4));
     }
-#endif
 
     void and32(RegisterID op1, RegisterID op2, RegisterID dest)
     {
@@ -384,7 +353,6 @@ public:
         or32(dataTempRegister, dest);
     }
     
-#if !defined(V4_BOOTSTRAP)
     void or32(RegisterID src, AbsoluteAddress dest)
     {
         move(TrustedImmPtr(dest.m_ptr), addressTempRegister);
@@ -392,7 +360,6 @@ public:
         or32(src, dataTempRegister);
         store32(dataTempRegister, addressTempRegister);
     }
-#endif
 
     void or32(TrustedImm32 imm, RegisterID dest)
     {
@@ -504,7 +471,6 @@ public:
         sub32(dataTempRegister, dest);
     }
 
-#if !defined(V4_BOOTSTRAP)
     void sub32(TrustedImm32 imm, AbsoluteAddress address)
     {
         load32(address.m_ptr, dataTempRegister);
@@ -521,7 +487,6 @@ public:
 
         store32(dataTempRegister, address.m_ptr);
     }
-#endif
 
     void xor32(Address src, RegisterID dest)
     {
@@ -698,13 +663,11 @@ public:
         load16(setupArmAddress(address), dest);
     }
 
-#if !defined(V4_BOOTSTRAP)
     void load32(const void* address, RegisterID dest)
     {
         move(TrustedImmPtr(address), addressTempRegister);
         m_assembler.ldr(dest, addressTempRegister, ARMThumbImmediate::makeUInt16(0));
     }
-#endif
     
     ConvertibleLoadLabel convertibleLoadPtr(Address address, RegisterID dest)
     {
@@ -809,7 +772,6 @@ public:
         store32(dataTempRegister, setupArmAddress(address));
     }
 
-#if !defined(V4_BOOTSTRAP)
     void store32(RegisterID src, const void* address)
     {
         move(TrustedImmPtr(address), addressTempRegister);
@@ -821,7 +783,6 @@ public:
         move(imm, dataTempRegister);
         store32(dataTempRegister, address);
     }
-#endif
 
     void store8(RegisterID src, BaseIndex address)
     {
@@ -839,7 +800,6 @@ public:
         store8(dataTempRegister, address);
     }
 
-#if !defined(V4_BOOTSTRAP)
     void store8(RegisterID src, void* address)
     {
         move(TrustedImmPtr(address), addressTempRegister);
@@ -851,7 +811,6 @@ public:
         move(imm, dataTempRegister);
         store8(dataTempRegister, address);
     }
-#endif
     
     void store16(RegisterID src, BaseIndex address)
     {
@@ -949,13 +908,11 @@ public:
             m_assembler.vmov(dest, src);
     }
 
-#if !defined(V4_BOOTSTRAP)
     void loadDouble(const void* address, FPRegisterID dest)
     {
         move(TrustedImmPtr(address), addressTempRegister);
         m_assembler.vldr(dest, addressTempRegister, 0);
     }
-#endif
 
     void storeDouble(FPRegisterID src, ImplicitAddress address)
     {
@@ -987,13 +944,11 @@ public:
         m_assembler.fsts(ARMRegisters::asSingle(src), base, offset);
     }
 
-#if !defined(V4_BOOTSTRAP)
     void storeDouble(FPRegisterID src, const void* address)
     {
         move(TrustedImmPtr(address), addressTempRegister);
         storeDouble(src, addressTempRegister);
     }
-#endif
 
     void storeDouble(FPRegisterID src, BaseIndex address)
     {
@@ -1027,13 +982,11 @@ public:
         m_assembler.vadd(dest, op1, op2);
     }
 
-#if !defined(V4_BOOTSTRAP)
     void addDouble(AbsoluteAddress address, FPRegisterID dest)
     {
         loadDouble(address.m_ptr, fpTempRegister);
         m_assembler.vadd(dest, dest, fpTempRegister);
     }
-#endif
 
     void divDouble(FPRegisterID src, FPRegisterID dest)
     {
@@ -1112,7 +1065,6 @@ public:
         m_assembler.vcvt_signedToFloatingPoint(dest, fpTempRegisterAsSingle());
     }
 
-#if !defined(V4_BOOTSTRAP)
     void convertInt32ToDouble(AbsoluteAddress address, FPRegisterID dest)
     {
         // Fixme: load directly into the fpr!
@@ -1120,7 +1072,6 @@ public:
         m_assembler.vmov(fpTempRegister, dataTempRegister, dataTempRegister);
         m_assembler.vcvt_signedToFloatingPoint(dest, fpTempRegisterAsSingle());
     }
-#endif
 
     void convertUInt32ToDouble(RegisterID src, FPRegisterID dest, RegisterID /*scratch*/)
     {
@@ -1316,12 +1267,10 @@ public:
             m_assembler.mov(dest, src);
     }
 
-#if !defined(V4_BOOTSTRAP)
     void move(TrustedImmPtr imm, RegisterID dest)
     {
         move(TrustedImm32(imm), dest);
     }
-#endif
 
     void swap(RegisterID reg1, RegisterID reg2)
     {
@@ -1462,7 +1411,6 @@ public:
         return branch32(cond, addressTempRegister, right);
     }
 
-#if !defined(V4_BOOTSTRAP)
     Jump branch32(RelationalCondition cond, AbsoluteAddress left, RegisterID right)
     {
         load32(left.m_ptr, dataTempRegister);
@@ -1475,7 +1423,6 @@ public:
         load32(left.m_ptr, addressTempRegister);
         return branch32(cond, addressTempRegister, right);
     }
-#endif
 
     Jump branch8(RelationalCondition cond, RegisterID left, TrustedImm32 right)
     {
@@ -1532,7 +1479,6 @@ public:
         return branchTest32(cond, addressTempRegister, mask);
     }
 
-#if !defined(V4_BOOTSTRAP)
     Jump branchTest8(ResultCondition cond, AbsoluteAddress address, TrustedImm32 mask = TrustedImm32(-1))
     {
         // use addressTempRegister incase the branchTest8 we call uses dataTempRegister. :-/
@@ -1540,7 +1486,6 @@ public:
         load8(Address(addressTempRegister), addressTempRegister);
         return branchTest32(cond, addressTempRegister, mask);
     }
-#endif
 
     void jump(RegisterID target)
     {
@@ -1554,14 +1499,12 @@ public:
         m_assembler.bx(dataTempRegister);
     }
     
-#if !defined(V4_BOOTSTRAP)
     void jump(AbsoluteAddress address)
     {
         move(TrustedImmPtr(address.m_ptr), dataTempRegister);
         load32(Address(dataTempRegister), dataTempRegister);
         m_assembler.bx(dataTempRegister);
     }
-#endif
 
 
     // Arithmetic control flow operations:
@@ -1602,7 +1545,6 @@ public:
         return branchAdd32(cond, dest, imm, dest);
     }
 
-#if !defined(V4_BOOTSTRAP)
     Jump branchAdd32(ResultCondition cond, TrustedImm32 imm, AbsoluteAddress dest)
     {
         // Move the high bits of the address into addressTempRegister,
@@ -1628,7 +1570,6 @@ public:
 
         return Jump(makeBranch(cond));
     }
-#endif
 
     Jump branchMul32(ResultCondition cond, RegisterID src1, RegisterID src2, RegisterID dest)
     {
@@ -1799,7 +1740,6 @@ public:
         return DataLabel32(this);
     }
 
-#if !defined(V4_BOOTSTRAP)
     ALWAYS_INLINE DataLabelPtr moveWithPatch(TrustedImmPtr imm, RegisterID dst)
     {
         padBeforePatch();
@@ -1827,7 +1767,6 @@ public:
         m_makeJumpPatchable = false;
         return PatchableJump(result);
     }
-#endif
 
     PatchableJump patchableBranchTest32(ResultCondition cond, RegisterID reg, TrustedImm32 mask = TrustedImm32(-1))
     {
@@ -1845,7 +1784,6 @@ public:
         return PatchableJump(result);
     }
 
-#if !defined(V4_BOOTSTRAP)
     PatchableJump patchableBranchPtrWithPatch(RelationalCondition cond, Address left, DataLabelPtr& dataLabel, TrustedImmPtr initialRightValue = TrustedImmPtr(0))
     {
         m_makeJumpPatchable = true;
@@ -1853,7 +1791,6 @@ public:
         m_makeJumpPatchable = false;
         return PatchableJump(result);
     }
-#endif
 
     PatchableJump patchableJump()
     {
@@ -1864,7 +1801,6 @@ public:
         return PatchableJump(result);
     }
 
-#if !defined(V4_BOOTSTRAP)
     ALWAYS_INLINE DataLabelPtr storePtrWithPatch(TrustedImmPtr initialValue, ImplicitAddress address)
     {
         DataLabelPtr label = moveWithPatch(initialValue, dataTempRegister);
@@ -1872,7 +1808,6 @@ public:
         return label;
     }
     ALWAYS_INLINE DataLabelPtr storePtrWithPatch(ImplicitAddress address) { return storePtrWithPatch(TrustedImmPtr(0), address); }
-#endif
 
     ALWAYS_INLINE Call tailRecursiveCall()
     {
@@ -1893,7 +1828,6 @@ public:
         return m_assembler.executableOffsetFor(location);
     }
 
-#if !defined(V4_BOOTSTRAP)
     static FunctionPtr readCallTarget(CodeLocationCall call)
     {
         return FunctionPtr(reinterpret_cast<void(*)()>(ARMv7Assembler::readCallTarget(call.dataLocation())));
@@ -1906,7 +1840,6 @@ public:
         const unsigned twoWordOpSize = 4;
         return label.labelAtOffset(-twoWordOpSize * 2);
     }
-#endif
 
     static void revertJumpReplacementToBranchPtrWithPatch(CodeLocationLabel instructionStart, RegisterID rd, void* initialValue)
     {
@@ -2024,7 +1957,6 @@ private:
     template <typename, template <typename> class> friend class LinkBufferBase;
     friend class RepatchBuffer;
 
-#if !defined(V4_BOOTSTRAP)
     static void linkCall(void* code, Call call, FunctionPtr function)
     {
         ARMv7Assembler::linkCall(code, call.m_label, function.value());
@@ -2039,7 +1971,6 @@ private:
     {
         ARMv7Assembler::relinkCall(call.dataLocation(), destination.executableAddress());
     }
-#endif
 
     bool m_makeJumpPatchable;
 };
diff --git a/src/3rdparty/masm/assembler/MacroAssemblerX86.h b/src/3rdparty/masm/assembler/MacroAssemblerX86.h
index e3e0bfe5e1..5cffa787ec 100644
--- a/src/3rdparty/masm/assembler/MacroAssemblerX86.h
+++ b/src/3rdparty/masm/assembler/MacroAssemblerX86.h
@@ -55,38 +55,6 @@ public:
     using MacroAssemblerX86Common::convertInt32ToDouble;
     using MacroAssemblerX86Common::branchTest8;
 
-#if defined(V4_BOOTSTRAP)
-    void loadPtr(ImplicitAddress address, RegisterID dest)
-    {
-        load32(address, dest);
-    }
-
-    void subPtr(TrustedImm32 imm, RegisterID dest)
-    {
-        sub32(imm, dest);
-    }
-
-    void addPtr(TrustedImm32 imm, RegisterID dest)
-    {
-        add32(imm, dest);
-    }
-
-    void addPtr(TrustedImm32 imm, RegisterID src, RegisterID dest)
-    {
-        add32(imm, src, dest);
-    }
-
-    void storePtr(RegisterID src, ImplicitAddress address)
-    {
-        store32(src, address);
-    }
-
-    Jump branchTest8(ResultCondition cond, ExtendedAddress address, TrustedImm32 mask = TrustedImm32(-1))
-    {
-        return branchTest8(cond, Address(address.base, address.offset), mask);
-    }
-#endif
-
     void add32(TrustedImm32 imm, RegisterID src, RegisterID dest)
     {
         m_assembler.leal_mr(imm.m_value, src, dest);
diff --git a/src/3rdparty/masm/assembler/MacroAssemblerX86_64.h b/src/3rdparty/masm/assembler/MacroAssemblerX86_64.h
index 64df58d121..0a6db0805b 100644
--- a/src/3rdparty/masm/assembler/MacroAssemblerX86_64.h
+++ b/src/3rdparty/masm/assembler/MacroAssemblerX86_64.h
@@ -53,33 +53,6 @@ public:
     using MacroAssemblerX86Common::loadDouble;
     using MacroAssemblerX86Common::convertInt32ToDouble;
 
-#if defined(V4_BOOTSTRAP)
-    void loadPtr(ImplicitAddress address, RegisterID dest)
-    {
-        load64(address, dest);
-    }
-
-    void subPtr(TrustedImm32 imm, RegisterID dest)
-    {
-        sub64(imm, dest);
-    }
-
-    void addPtr(TrustedImm32 imm, RegisterID dest)
-    {
-        add64(imm, dest);
-    }
-
-    void addPtr(TrustedImm32 imm, RegisterID src, RegisterID dest)
-    {
-        add64(imm, src, dest);
-    }
-
-    void storePtr(RegisterID src, ImplicitAddress address)
-    {
-        store64(src, address);
-    }
-#endif
-
     void add32(TrustedImm32 imm, AbsoluteAddress address)
     {
         move(TrustedImmPtr(address.m_ptr), scratchRegister);
diff --git a/src/3rdparty/masm/assembler/X86Assembler.h b/src/3rdparty/masm/assembler/X86Assembler.h
index 2257cb2b9a..e8ae687036 100644
--- a/src/3rdparty/masm/assembler/X86Assembler.h
+++ b/src/3rdparty/masm/assembler/X86Assembler.h
@@ -255,47 +255,6 @@ public:
     {
     }
 
-#if defined(V4_BOOTSTRAP)
-    template <typename LabelType>
-    class Jump {
-        template<class TemplateAssemblerType>
-        friend class AbstractMacroAssembler;
-        friend class Call;
-        template <typename, template <typename> class> friend class LinkBufferBase;
-    public:
-        Jump()
-        {
-        }
-
-        Jump(AssemblerLabel jmp)
-            : m_label(jmp)
-        {
-        }
-
-        LabelType label() const
-        {
-            LabelType result;
-            result.m_label = m_label;
-            return result;
-        }
-
-        void link(AbstractMacroAssembler<X86Assembler>* masm) const
-        {
-            masm->m_assembler.linkJump(m_label, masm->m_assembler.label());
-        }
-
-        void linkTo(LabelType label, AbstractMacroAssembler<X86Assembler>* masm) const
-        {
-            masm->m_assembler.linkJump(m_label, label.label());
-        }
-
-        bool isSet() const { return m_label.isSet(); }
-
-    private:
-        AssemblerLabel m_label;
-    };
-#endif
-
     // Stack operations:
 
     void push_r(RegisterID reg)
diff --git a/src/imports/imports.pro b/src/imports/imports.pro
index 901c263be5..6b31dfc65d 100644
--- a/src/imports/imports.pro
+++ b/src/imports/imports.pro
@@ -1,4 +1,5 @@
 TEMPLATE = subdirs
+QT_FOR_CONFIG += qml-private
 
 SUBDIRS += \
     builtins \
@@ -6,6 +7,7 @@ SUBDIRS += \
     models \
     labsmodels
 
+qtConfig(qml-worker-script): SUBDIRS += workerscript
 qtConfig(thread): SUBDIRS += folderlistmodel
 qtHaveModule(sql): SUBDIRS += localstorage
 qtConfig(settings): SUBDIRS += settings
diff --git a/src/imports/localstorage/plugin.cpp b/src/imports/localstorage/plugin.cpp
index 0aad0d7c16..9004d1ee6f 100644
--- a/src/imports/localstorage/plugin.cpp
+++ b/src/imports/localstorage/plugin.cpp
@@ -85,7 +85,7 @@ QT_BEGIN_NAMESPACE
 }
 
 
-class QQmlSqlDatabaseData : public QV8Engine::Deletable
+class QQmlSqlDatabaseData : public QV4::ExecutionEngine::Deletable
 {
 public:
     QQmlSqlDatabaseData(QV4::ExecutionEngine *engine);
diff --git a/src/imports/qtquick2/plugin.cpp b/src/imports/qtquick2/plugin.cpp
index a5a2c73ced..efa05c349c 100644
--- a/src/imports/qtquick2/plugin.cpp
+++ b/src/imports/qtquick2/plugin.cpp
@@ -42,6 +42,9 @@
 #if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
 #include <QtQml/private/qqmlengine_p.h>
 #include <QtQmlModels/private/qqmlmodelsmodule_p.h>
+#if QT_CONFIG(qml_worker_script)
+#include <QtQmlWorkerScript/private/qqmlworkerscriptmodule_p.h>
+#endif
 #endif // QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
 
 #include <private/qtquick2_p.h>
@@ -63,6 +66,9 @@ public:
 #if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
         QQmlEnginePrivate::registerQuickTypes();
         QQmlModelsModule::registerQuickTypes();
+#if QT_CONFIG(qml_worker_script)
+        QQmlWorkerScriptModule::registerQuickTypes();
+#endif
 #endif
         QQmlQtQuick2Module::defineModule();
 
diff --git a/src/imports/qtquick2/qtquick2.pro b/src/imports/qtquick2/qtquick2.pro
index 1b45d69eb7..8543049ead 100644
--- a/src/imports/qtquick2/qtquick2.pro
+++ b/src/imports/qtquick2/qtquick2.pro
@@ -8,4 +8,6 @@ SOURCES += \
 
 QT += quick-private qml-private qmlmodels-private
 
+qtConfig(qml-worker-script): QT += qmlworkerscript-private
+
 load(qml_plugin)
diff --git a/src/imports/statemachine/signaltransition.cpp b/src/imports/statemachine/signaltransition.cpp
index 52dffe9004..468f2020c7 100644
--- a/src/imports/statemachine/signaltransition.cpp
+++ b/src/imports/statemachine/signaltransition.cpp
@@ -184,7 +184,7 @@ void SignalTransition::connectTriggered()
     m_signalExpression = expression;
 }
 
-void SignalTransitionParser::verifyBindings(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &props)
+void SignalTransitionParser::verifyBindings(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &props)
 {
     for (int ii = 0; ii < props.count(); ++ii) {
         const QV4::CompiledData::Binding *binding = props.at(ii);
@@ -203,7 +203,9 @@ void SignalTransitionParser::verifyBindings(const QQmlRefPointer<QV4::CompiledDa
     }
 }
 
-void SignalTransitionParser::applyBindings(QObject *object, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings)
+void SignalTransitionParser::applyBindings(
+        QObject *object, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit,
+        const QList<const QV4::CompiledData::Binding *> &bindings)
 {
     SignalTransition *st = qobject_cast<SignalTransition*>(object);
     st->m_compilationUnit = compilationUnit;
diff --git a/src/imports/statemachine/signaltransition.h b/src/imports/statemachine/signaltransition.h
index 90e6f96fbc..f005c5e9b1 100644
--- a/src/imports/statemachine/signaltransition.h
+++ b/src/imports/statemachine/signaltransition.h
@@ -89,7 +89,7 @@ private:
     QJSValue m_signal;
     QQmlScriptString m_guard;
     bool m_complete;
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> m_compilationUnit;
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> m_compilationUnit;
     QList<const QV4::CompiledData::Binding *> m_bindings;
     QQmlBoundSignalExpressionPointer m_signalExpression;
 };
@@ -97,8 +97,8 @@ private:
 class SignalTransitionParser : public QQmlCustomParser
 {
 public:
-    void verifyBindings(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &props) override;
-    void applyBindings(QObject *object, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings) override;
+    void verifyBindings(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &props) override;
+    void applyBindings(QObject *object, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings) override;
 };
 
 QT_END_NAMESPACE
diff --git a/src/imports/statemachine/statemachine.cpp b/src/imports/statemachine/statemachine.cpp
index ca6c59b6ac..a983644018 100644
--- a/src/imports/statemachine/statemachine.cpp
+++ b/src/imports/statemachine/statemachine.cpp
@@ -51,6 +51,7 @@ StateMachine::StateMachine(QObject *parent)
     : QStateMachine(parent), m_completed(false), m_running(false)
 {
     connect(this, SIGNAL(runningChanged(bool)), SIGNAL(qmlRunningChanged()));
+    connect(this, SIGNAL(childModeChanged()), SLOT(checkChildMode()));
 }
 
 bool StateMachine::isRunning() const
@@ -66,6 +67,15 @@ void StateMachine::setRunning(bool running)
         m_running = running;
 }
 
+void StateMachine::checkChildMode()
+{
+    if (childMode() != QState::ExclusiveStates) {
+        qmlWarning(this) << "Setting the childMode of a StateMachine to anything else than\n"
+                            "QState.ExclusiveStates will result in an invalid state machine,\n"
+                            "and can lead to incorrect behavior!";
+    }
+}
+
 void StateMachine::componentComplete()
 {
     if (QStateMachine::initialState() == nullptr && childMode() == QState::ExclusiveStates)
@@ -129,6 +139,9 @@ QQmlListProperty<QObject> StateMachine::children()
     erroneous state, the machine will stop executing and an error message will
     be printed to the console.
 
+    \warning Setting the childMode of a StateMachine to anything else than QState::ExclusiveStates
+    will result in an invalid state machine, and can lead to incorrect behavior.
+
     \clearfloat
 
     \sa QAbstractState, State, SignalTransition, TimeoutTransition, HistoryState {The Declarative State Machine Framework}
diff --git a/src/imports/statemachine/statemachine.h b/src/imports/statemachine/statemachine.h
index cb0ab43f8b..1fa7a9da43 100644
--- a/src/imports/statemachine/statemachine.h
+++ b/src/imports/statemachine/statemachine.h
@@ -69,6 +69,9 @@ public:
     bool isRunning() const;
     void setRunning(bool running);
 
+private Q_SLOTS:
+    void checkChildMode();
+
 Q_SIGNALS:
     void childrenChanged();
     /*!
diff --git a/src/imports/workerscript/dependencies.json b/src/imports/workerscript/dependencies.json
new file mode 100644
index 0000000000..0d4f101c7a
--- /dev/null
+++ b/src/imports/workerscript/dependencies.json
@@ -0,0 +1,2 @@
+[
+]
diff --git a/src/imports/workerscript/plugin.cpp b/src/imports/workerscript/plugin.cpp
new file mode 100644
index 0000000000..5b3bff7934
--- /dev/null
+++ b/src/imports/workerscript/plugin.cpp
@@ -0,0 +1,81 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtQmlWorkerScript/private/qqmlworkerscriptmodule_p.h>
+#include <QtQml/qqmlextensionplugin.h>
+#include <QtQml/qqml.h>
+
+QT_BEGIN_NAMESPACE
+
+/*!
+    \qmlmodule QtQml.WorkerScript 2.\QtMinorVersion
+    \title Qt QML WorkerScript QML Types
+    \ingroup qmlmodules
+    \brief Provides QML types for worker scripts
+    \since 5.14
+
+    This QML module contains types for using worker scripts.
+
+    To use the types in this module, import the module with the following line:
+
+    \qml \QtMinorVersion
+    import QtQml.WorkerScript 2.\1
+    \endqml
+*/
+
+class QtQmlWorkerScriptPlugin : public QQmlExtensionPlugin
+{
+    Q_OBJECT
+    Q_PLUGIN_METADATA(IID QQmlExtensionInterface_iid)
+public:
+    QtQmlWorkerScriptPlugin(QObject *parent = nullptr) : QQmlExtensionPlugin(parent) { }
+    void registerTypes(const char *uri) override
+    {
+        Q_ASSERT(QLatin1String(uri) == QLatin1String("QtQml.WorkerScript"));
+
+        QQmlWorkerScriptModule::defineModule();
+
+        // Auto-increment the import to stay in sync with ALL future QtQuick minor versions from 5.11 onward
+        qmlRegisterModule(uri, 2, QT_VERSION_MINOR);
+    }
+};
+
+QT_END_NAMESPACE
+
+#include "plugin.moc"
diff --git a/src/imports/workerscript/qmldir b/src/imports/workerscript/qmldir
new file mode 100644
index 0000000000..0e811d1dbc
--- /dev/null
+++ b/src/imports/workerscript/qmldir
@@ -0,0 +1,3 @@
+module QtQml.WorkerScript
+plugin workerscriptsplugin
+classname QtQmlWorkerScriptPlugin
diff --git a/src/imports/workerscript/workerscript.pro b/src/imports/workerscript/workerscript.pro
new file mode 100644
index 0000000000..d48e285bda
--- /dev/null
+++ b/src/imports/workerscript/workerscript.pro
@@ -0,0 +1,11 @@
+CXX_MODULE = qml
+TARGET  = workerscriptplugin
+TARGETPATH = QtQml/WorkerScript.2
+IMPORT_VERSION = 2.$$QT_MINOR_VERSION
+
+SOURCES += \
+    plugin.cpp
+
+QT = qml-private qmlworkerscript-private
+
+load(qml_plugin)
diff --git a/src/particles/qquickv4particledata.cpp b/src/particles/qquickv4particledata.cpp
index 383444a808..459797f977 100644
--- a/src/particles/qquickv4particledata.cpp
+++ b/src/particles/qquickv4particledata.cpp
@@ -290,7 +290,7 @@ struct QV4ParticleData : public QV4::Object
 
 DEFINE_OBJECT_VTABLE(QV4ParticleData);
 
-class QV4ParticleDataDeletable : public QV8Engine::Deletable
+class QV4ParticleDataDeletable : public QV4::ExecutionEngine::Deletable
 {
 public:
     QV4ParticleDataDeletable(QV4::ExecutionEngine *engine);
diff --git a/src/plugins/qmltooling/qmldbg_debugger/qv4debugjob.cpp b/src/plugins/qmltooling/qmldbg_debugger/qv4debugjob.cpp
index b424ef9f6c..61fea96e2f 100644
--- a/src/plugins/qmltooling/qmldbg_debugger/qv4debugjob.cpp
+++ b/src/plugins/qmltooling/qmldbg_debugger/qv4debugjob.cpp
@@ -264,7 +264,7 @@ GatherSourcesJob::GatherSourcesJob(QV4::ExecutionEngine *engine)
 
 void GatherSourcesJob::run()
 {
-    for (QV4::CompiledData::CompilationUnit *unit : engine->compilationUnits) {
+    for (QV4::ExecutableCompilationUnit *unit : engine->compilationUnits) {
         QString fileName = unit->fileName();
         if (!fileName.isEmpty())
             sources.append(fileName);
diff --git a/src/plugins/qmltooling/qmldbg_inspector/globalinspector.cpp b/src/plugins/qmltooling/qmldbg_inspector/globalinspector.cpp
index bac4e01df1..012730902b 100644
--- a/src/plugins/qmltooling/qmldbg_inspector/globalinspector.cpp
+++ b/src/plugins/qmltooling/qmldbg_inspector/globalinspector.cpp
@@ -48,6 +48,7 @@
 #include <private/qversionedpacket_p.h>
 
 #include <QtGui/qwindow.h>
+#include <QtCore/qregularexpression.h>
 
 //INSPECTOR SERVICE PROTOCOL
 // <HEADER><COMMAND><DATA>
@@ -273,8 +274,10 @@ QString GlobalInspector::titleForItem(QQuickItem *item) const
     QString className = QLatin1String(item->metaObject()->className());
     QString objectStringId = idStringForObject(item);
 
-    className.remove(QRegExp(QLatin1String("_QMLTYPE_\\d+")));
-    className.remove(QRegExp(QLatin1String("_QML_\\d+")));
+#if QT_CONFIG(regularexpression)
+    className.remove(QRegularExpression(QLatin1String("_QMLTYPE_\\d+")));
+    className.remove(QRegularExpression(QLatin1String("_QML_\\d+")));
+#endif
     if (className.startsWith(QLatin1String("QQuick")))
         className = className.mid(6);
 
diff --git a/src/plugins/qmltooling/qmldbg_server/qqmldebugserver.cpp b/src/plugins/qmltooling/qmldbg_server/qqmldebugserver.cpp
index 8293e88038..2d5282b48c 100644
--- a/src/plugins/qmltooling/qmldbg_server/qqmldebugserver.cpp
+++ b/src/plugins/qmltooling/qmldbg_server/qqmldebugserver.cpp
@@ -355,14 +355,12 @@ void QQmlDebugServerImpl::parseArguments()
             if (argsNext == argsItEnd)
                 break;
             if (ok) {
-                const QString nextArgument = argsNext->toString();
-
-                // Don't use QStringLiteral here. QRegExp has a global cache and will save an implicitly
-                // shared copy of the passed string. That copy isn't properly detached when the library
-                // is unloaded if the original string lives in the library's .rodata
-                if (nextArgument.contains(QRegExp(QLatin1String("^\\s*\\d+\\s*$")))) {
-                    portTo = nextArgument.toInt(&ok);
+                portTo = argsNext->toString().toInt(&ok);
+                if (ok) {
                     ++argsIt;
+                } else {
+                    portTo = portFrom;
+                    ok = true;
                 }
             }
         } else if (strArgument.startsWith(QLatin1String("host:"))) {
diff --git a/src/qml/compiler/compiler.pri b/src/qml/compiler/compiler.pri
index da3c173545..3291d6e1f5 100644
--- a/src/qml/compiler/compiler.pri
+++ b/src/qml/compiler/compiler.pri
@@ -10,7 +10,6 @@ HEADERS += \
     $$PWD/qv4compilerscanfunctions_p.h \
     $$PWD/qv4codegen_p.h \
     $$PWD/qqmlirbuilder_p.h \
-    $$PWD/qqmltypecompiler_p.h \
     $$PWD/qv4instr_moth_p.h \
     $$PWD/qv4bytecodehandler_p.h
 
@@ -28,17 +27,22 @@ SOURCES += \
 !qmldevtools_build {
 
 HEADERS += \
+    $$PWD/qqmlirloader_p.h \
+    $$PWD/qqmlpropertyresolver_p.h \
     $$PWD/qqmltypecompiler_p.h \
     $$PWD/qqmlpropertycachecreator_p.h \
     $$PWD/qqmlpropertyvalidator_p.h \
-    $$PWD/qv4compilationunitmapper_p.h
-
+    $$PWD/qv4compilationunitmapper_p.h \
+    $$PWD/qv4executablecompilationunit_p.h
 
 SOURCES += \
+    $$PWD/qqmlirloader.cpp \
+    $$PWD/qqmlpropertyresolver.cpp \
     $$PWD/qqmltypecompiler.cpp \
     $$PWD/qqmlpropertycachecreator.cpp \
     $$PWD/qqmlpropertyvalidator.cpp \
-    $$PWD/qv4compilationunitmapper.cpp
+    $$PWD/qv4compilationunitmapper.cpp \
+    $$PWD/qv4executablecompilationunit.cpp
 
 unix: SOURCES += $$PWD/qv4compilationunitmapper_unix.cpp
 else: SOURCES += $$PWD/qv4compilationunitmapper_win.cpp
diff --git a/src/qml/compiler/qqmlirbuilder.cpp b/src/qml/compiler/qqmlirbuilder.cpp
index 6e077ec44c..6f46648572 100644
--- a/src/qml/compiler/qqmlirbuilder.cpp
+++ b/src/qml/compiler/qqmlirbuilder.cpp
@@ -48,12 +48,6 @@
 #include <QCryptographicHash>
 #include <cmath>
 
-#ifndef V4_BOOTSTRAP
-#include <private/qqmlglobal_p.h>
-#include <private/qqmltypeloader_p.h>
-#include <private/qqmlengine_p.h>
-#endif
-
 #ifdef CONST
 #undef CONST
 #endif
@@ -61,11 +55,6 @@
 QT_USE_NAMESPACE
 
 static const quint32 emptyStringIndex = 0;
-
-#if 0 //ndef V4_BOOTSTRAP
-DEFINE_BOOL_CONFIG_OPTION(lookupHints, QML_LOOKUP_HINTS);
-#endif // V4_BOOTSTRAP
-
 using namespace QmlIR;
 
 #define COMPILE_EXCEPTION(location, desc) \
@@ -1559,20 +1548,12 @@ void QmlUnitGenerator::generate(Document &output, const QV4::CompiledData::Depen
     output.jsGenerator.stringTable.registerString(output.jsModule.fileName);
     output.jsGenerator.stringTable.registerString(output.jsModule.finalUrl);
 
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> compilationUnit = output.javaScriptCompilationUnit;
-
-    const QV4::CompiledData::Unit *jsUnit = nullptr;
-    std::function<QV4::CompiledData::QmlUnit *(QV4::CompiledData::QmlUnit *, uint)> unitFinalizer
-            = [](QV4::CompiledData::QmlUnit *unit, uint) {
-        return unit;
-    };
+    QV4::CompiledData::Unit *jsUnit = nullptr;
 
     // We may already have unit data if we're loading an ahead-of-time generated cache file.
-    if (compilationUnit->data) {
-        jsUnit = compilationUnit->data;
-#ifndef V4_BOOTSTRAP
-        output.javaScriptCompilationUnit->dynamicStrings = output.jsGenerator.stringTable.allStrings();
-#endif
+    if (output.javaScriptCompilationUnit.data) {
+        jsUnit = const_cast<QV4::CompiledData::Unit *>(output.javaScriptCompilationUnit.data);
+        output.javaScriptCompilationUnit.dynamicStrings = output.jsGenerator.stringTable.allStrings();
     } else {
         QV4::CompiledData::Unit *createdUnit;
         jsUnit = createdUnit = output.jsGenerator.generateUnit();
@@ -1584,38 +1565,17 @@ void QmlUnitGenerator::generate(Document &output, const QV4::CompiledData::Depen
                 break;
             }
         }
-        // This unit's memory was allocated with malloc on the heap, so it's
-        // definitely not suitable for StaticData access.
-        createdUnit->flags &= ~QV4::CompiledData::Unit::StaticData;
 
-#ifndef V4_BOOTSTRAP
         if (dependencyHasher) {
-            QCryptographicHash hash(QCryptographicHash::Md5);
-            if (dependencyHasher(&hash)) {
-                QByteArray checksum = hash.result();
-                Q_ASSERT(checksum.size() == sizeof(createdUnit->dependencyMD5Checksum));
-                memcpy(createdUnit->dependencyMD5Checksum, checksum.constData(), sizeof(createdUnit->dependencyMD5Checksum));
+            const QByteArray checksum = dependencyHasher();
+            if (checksum.size() == sizeof(createdUnit->dependencyMD5Checksum)) {
+                memcpy(createdUnit->dependencyMD5Checksum, checksum.constData(),
+                       sizeof(createdUnit->dependencyMD5Checksum));
             }
         }
-#else
-        Q_UNUSED(dependencyHasher);
-#endif
+
         createdUnit->sourceFileIndex = output.jsGenerator.stringTable.getStringId(output.jsModule.fileName);
         createdUnit->finalUrlIndex = output.jsGenerator.stringTable.getStringId(output.jsModule.finalUrl);
-
-        // Combine the qml data into the general unit data.
-        unitFinalizer = [&jsUnit](QV4::CompiledData::QmlUnit *qmlUnit, uint qmlDataSize) {
-            void *ptr = const_cast<QV4::CompiledData::Unit*>(jsUnit);
-            QV4::CompiledData::Unit *newUnit = (QV4::CompiledData::Unit *)realloc(ptr, jsUnit->unitSize + qmlDataSize);
-            jsUnit = newUnit;
-            newUnit->offsetToQmlUnit = newUnit->unitSize;
-            newUnit->unitSize += qmlDataSize;
-            memcpy(const_cast<QV4::CompiledData::QmlUnit *>(newUnit->qmlUnit()), qmlUnit, qmlDataSize);
-            free(const_cast<QV4::CompiledData::QmlUnit*>(qmlUnit));
-            qmlUnit = nullptr;
-            newUnit->generateChecksum();
-            return const_cast<QV4::CompiledData::QmlUnit*>(newUnit->qmlUnit());
-        };
     }
 
     // No more new strings after this point, we're calculating offsets.
@@ -1782,7 +1742,16 @@ void QmlUnitGenerator::generate(Document &output, const QV4::CompiledData::Depen
         }
     }
 
-    qmlUnit = unitFinalizer(qmlUnit, totalSize);
+    if (!output.javaScriptCompilationUnit.data) {
+        // Combine the qml data into the general unit data.
+        jsUnit = static_cast<QV4::CompiledData::Unit *>(realloc(jsUnit, jsUnit->unitSize + totalSize));
+        jsUnit->offsetToQmlUnit = jsUnit->unitSize;
+        jsUnit->unitSize += totalSize;
+        memcpy(jsUnit->qmlUnit(), qmlUnit, totalSize);
+        free(qmlUnit);
+        jsUnit->generateChecksum();
+        qmlUnit = jsUnit->qmlUnit();
+    }
 
     static const bool showStats = qEnvironmentVariableIsSet("QML_SHOW_UNIT_STATS");
     if (showStats) {
@@ -1806,7 +1775,8 @@ void QmlUnitGenerator::generate(Document &output, const QV4::CompiledData::Depen
         qDebug() << "    " << totalStringSize << "bytes total strings";
     }
 
-    compilationUnit->setUnitData(jsUnit, qmlUnit, output.jsModule.fileName, output.jsModule.finalUrl);
+    output.javaScriptCompilationUnit.setUnitData(jsUnit, qmlUnit, output.jsModule.fileName,
+                                                 output.jsModule.finalUrl);
 }
 
 char *QmlUnitGenerator::writeBindings(char *bindingPtr, const Object *o, BindingFilter filter) const
@@ -1911,214 +1881,3 @@ QVector<int> JSCodeGen::generateJSCodeForFunctionsAndBindings(const QList<Compil
 
     return runtimeFunctionIndices;
 }
-
-#ifndef V4_BOOTSTRAP
-
-QQmlPropertyData *PropertyResolver::property(const QString &name, bool *notInRevision, RevisionCheck check) const
-{
-    if (notInRevision) *notInRevision = false;
-
-    QQmlPropertyData *d = cache->property(name, nullptr, nullptr);
-
-    // Find the first property
-    while (d && d->isFunction())
-        d = cache->overrideData(d);
-
-    if (check != IgnoreRevision && d && !cache->isAllowedInRevision(d)) {
-        if (notInRevision) *notInRevision = true;
-        return nullptr;
-    } else {
-        return d;
-    }
-}
-
-
-QQmlPropertyData *PropertyResolver::signal(const QString &name, bool *notInRevision) const
-{
-    if (notInRevision) *notInRevision = false;
-
-    QQmlPropertyData *d = cache->property(name, nullptr, nullptr);
-    if (notInRevision) *notInRevision = false;
-
-    while (d && !(d->isFunction()))
-        d = cache->overrideData(d);
-
-    if (d && !cache->isAllowedInRevision(d)) {
-        if (notInRevision) *notInRevision = true;
-        return nullptr;
-    } else if (d && d->isSignal()) {
-        return d;
-    }
-
-    if (name.endsWith(QLatin1String("Changed"))) {
-        QString propName = name.mid(0, name.length() - static_cast<int>(strlen("Changed")));
-
-        d = property(propName, notInRevision);
-        if (d)
-            return cache->signal(d->notifyIndex());
-    }
-
-    return nullptr;
-}
-
-IRLoader::IRLoader(const QV4::CompiledData::Unit *qmlData, QmlIR::Document *output)
-    : unit(qmlData)
-    , output(output)
-{
-    pool = output->jsParserEngine.pool();
-}
-
-void IRLoader::load()
-{
-    output->jsGenerator.stringTable.initializeFromBackingUnit(unit);
-
-    const QV4::CompiledData::QmlUnit *qmlUnit = unit->qmlUnit();
-
-    for (quint32 i = 0; i < qmlUnit->nImports; ++i)
-        output->imports << qmlUnit->importAt(i);
-
-    if (unit->flags & QV4::CompiledData::Unit::IsSingleton) {
-        QmlIR::Pragma *p = New<QmlIR::Pragma>();
-        p->location = QV4::CompiledData::Location();
-        p->type = QmlIR::Pragma::PragmaSingleton;
-        output->pragmas << p;
-    }
-
-    for (uint i = 0; i < qmlUnit->nObjects; ++i) {
-        const QV4::CompiledData::Object *serializedObject = qmlUnit->objectAt(i);
-        QmlIR::Object *object = loadObject(serializedObject);
-        output->objects.append(object);
-    }
-}
-
-struct FakeExpression : public QQmlJS::AST::NullExpression
-{
-    FakeExpression(int start, int length)
-        : location(start, length)
-    {}
-
-    virtual QQmlJS::AST::SourceLocation firstSourceLocation() const
-    { return location; }
-
-    virtual QQmlJS::AST::SourceLocation lastSourceLocation() const
-    { return location; }
-
-private:
-    QQmlJS::AST::SourceLocation location;
-};
-
-QmlIR::Object *IRLoader::loadObject(const QV4::CompiledData::Object *serializedObject)
-{
-    QmlIR::Object *object = pool->New<QmlIR::Object>();
-    object->init(pool, serializedObject->inheritedTypeNameIndex, serializedObject->idNameIndex);
-
-    object->indexOfDefaultPropertyOrAlias = serializedObject->indexOfDefaultPropertyOrAlias;
-    object->defaultPropertyIsAlias = serializedObject->defaultPropertyIsAlias;
-    object->flags = serializedObject->flags;
-    object->id = serializedObject->id;
-    object->location = serializedObject->location;
-    object->locationOfIdProperty = serializedObject->locationOfIdProperty;
-
-    QVector<int> functionIndices;
-    functionIndices.reserve(serializedObject->nFunctions + serializedObject->nBindings / 2);
-
-    for (uint i = 0; i < serializedObject->nBindings; ++i) {
-        QmlIR::Binding *b = pool->New<QmlIR::Binding>();
-        *static_cast<QV4::CompiledData::Binding*>(b) = serializedObject->bindingTable()[i];
-        object->bindings->append(b);
-        if (b->type == QV4::CompiledData::Binding::Type_Script) {
-            functionIndices.append(b->value.compiledScriptIndex);
-            b->value.compiledScriptIndex = functionIndices.count() - 1;
-
-            QmlIR::CompiledFunctionOrExpression *foe = pool->New<QmlIR::CompiledFunctionOrExpression>();
-            foe->nameIndex = 0;
-
-            QQmlJS::AST::ExpressionNode *expr;
-
-            if (b->stringIndex != quint32(0)) {
-                const int start = output->code.length();
-                const QString script = output->stringAt(b->stringIndex);
-                const int length = script.length();
-                output->code.append(script);
-                expr = new (pool) FakeExpression(start, length);
-            } else
-                expr = new (pool) QQmlJS::AST::NullExpression();
-            foe->node = new (pool) QQmlJS::AST::ExpressionStatement(expr); // dummy
-            object->functionsAndExpressions->append(foe);
-        }
-    }
-
-    Q_ASSERT(object->functionsAndExpressions->count == functionIndices.count());
-
-    for (uint i = 0; i < serializedObject->nSignals; ++i) {
-        const QV4::CompiledData::Signal *serializedSignal = serializedObject->signalAt(i);
-        QmlIR::Signal *s = pool->New<QmlIR::Signal>();
-        s->nameIndex = serializedSignal->nameIndex;
-        s->location = serializedSignal->location;
-        s->parameters = pool->New<QmlIR::PoolList<QmlIR::SignalParameter> >();
-
-        for (uint i = 0; i < serializedSignal->nParameters; ++i) {
-            QmlIR::SignalParameter *p = pool->New<QmlIR::SignalParameter>();
-            *static_cast<QV4::CompiledData::Parameter*>(p) = *serializedSignal->parameterAt(i);
-            s->parameters->append(p);
-        }
-
-        object->qmlSignals->append(s);
-    }
-
-    for (uint i = 0; i < serializedObject->nEnums; ++i) {
-        const QV4::CompiledData::Enum *serializedEnum = serializedObject->enumAt(i);
-        QmlIR::Enum *e = pool->New<QmlIR::Enum>();
-        e->nameIndex = serializedEnum->nameIndex;
-        e->location = serializedEnum->location;
-        e->enumValues = pool->New<QmlIR::PoolList<QmlIR::EnumValue> >();
-
-        for (uint i = 0; i < serializedEnum->nEnumValues; ++i) {
-            QmlIR::EnumValue *v = pool->New<QmlIR::EnumValue>();
-            *static_cast<QV4::CompiledData::EnumValue*>(v) = *serializedEnum->enumValueAt(i);
-            e->enumValues->append(v);
-        }
-
-        object->qmlEnums->append(e);
-    }
-
-    const QV4::CompiledData::Property *serializedProperty = serializedObject->propertyTable();
-    for (uint i = 0; i < serializedObject->nProperties; ++i, ++serializedProperty) {
-        QmlIR::Property *p = pool->New<QmlIR::Property>();
-        *static_cast<QV4::CompiledData::Property*>(p) = *serializedProperty;
-        object->properties->append(p);
-    }
-
-    {
-        const QV4::CompiledData::Alias *serializedAlias = serializedObject->aliasTable();
-        for (uint i = 0; i < serializedObject->nAliases; ++i, ++serializedAlias) {
-            QmlIR::Alias *a = pool->New<QmlIR::Alias>();
-            *static_cast<QV4::CompiledData::Alias*>(a) = *serializedAlias;
-            object->aliases->append(a);
-        }
-    }
-
-    const quint32_le *functionIdx = serializedObject->functionOffsetTable();
-    for (uint i = 0; i < serializedObject->nFunctions; ++i, ++functionIdx) {
-        QmlIR::Function *f = pool->New<QmlIR::Function>();
-        const QV4::CompiledData::Function *compiledFunction = unit->functionAt(*functionIdx);
-
-        functionIndices.append(*functionIdx);
-        f->index = functionIndices.count() - 1;
-        f->location = compiledFunction->location;
-        f->nameIndex = compiledFunction->nameIndex;
-
-        f->formals.allocate(pool, int(compiledFunction->nFormals));
-        const quint32_le *formalNameIdx = compiledFunction->formalsTable();
-        for (uint i = 0; i < compiledFunction->nFormals; ++i, ++formalNameIdx)
-            f->formals[i] = *formalNameIdx;
-
-        object->functions->append(f);
-    }
-
-    object->runtimeFunctionIndices.allocate(pool, functionIndices);
-
-    return object;
-}
-
-#endif // V4_BOOTSTRAP
diff --git a/src/qml/compiler/qqmlirbuilder_p.h b/src/qml/compiler/qqmlirbuilder_p.h
index 298fe7dd92..b49eaee420 100644
--- a/src/qml/compiler/qqmlirbuilder_p.h
+++ b/src/qml/compiler/qqmlirbuilder_p.h
@@ -65,11 +65,11 @@ QT_BEGIN_NAMESPACE
 class QQmlPropertyCache;
 class QQmlContextData;
 class QQmlTypeNameCache;
+struct QQmlIRLoader;
 
 namespace QmlIR {
 
 struct Document;
-struct IRLoader;
 
 template <typename T>
 struct PoolList
@@ -347,7 +347,7 @@ public:
     const quint32 *namedObjectsInComponentTable() const { return namedObjectsInComponent.begin(); }
 
 private:
-    friend struct IRLoader;
+    friend struct ::QQmlIRLoader;
 
     PoolList<Property> *properties;
     PoolList<Alias> *aliases;
@@ -379,7 +379,7 @@ struct Q_QML_PRIVATE_EXPORT Document
     QVector<Object*> objects;
     QV4::Compiler::JSUnitGenerator jsGenerator;
 
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> javaScriptCompilationUnit;
+    QV4::CompiledData::CompilationUnit javaScriptCompilationUnit;
 
     int registerString(const QString &str) { return jsGenerator.registerString(str); }
     QString stringAt(int index) const { return jsGenerator.stringForIndex(index); }
@@ -508,32 +508,6 @@ private:
     char *writeBindings(char *bindingPtr, const Object *o, BindingFilter filter) const;
 };
 
-#ifndef V4_BOOTSTRAP
-struct Q_QML_EXPORT PropertyResolver
-{
-    PropertyResolver(const QQmlRefPointer<QQmlPropertyCache> &cache)
-        : cache(cache)
-    {}
-
-    QQmlPropertyData *property(int index) const
-    {
-        return cache->property(index);
-    }
-
-    enum RevisionCheck {
-        CheckRevision,
-        IgnoreRevision
-    };
-
-    QQmlPropertyData *property(const QString &name, bool *notInRevision = nullptr, RevisionCheck check = CheckRevision) const;
-
-    // This code must match the semantics of QQmlPropertyPrivate::findSignalByName
-    QQmlPropertyData *signal(const QString &name, bool *notInRevision) const;
-
-    QQmlRefPointer<QQmlPropertyCache> cache;
-};
-#endif
-
 struct Q_QML_PRIVATE_EXPORT JSCodeGen : public QV4::Compiler::Codegen
 {
     JSCodeGen(const QString &sourceCode, QV4::Compiler::JSUnitGenerator *jsUnitGenerator, QV4::Compiler::Module *jsModule,
@@ -550,21 +524,6 @@ private:
     const QV4::Compiler::StringTableGenerator *stringPool;
 };
 
-struct Q_QML_PRIVATE_EXPORT IRLoader {
-    IRLoader(const QV4::CompiledData::Unit *unit, QmlIR::Document *output);
-
-    void load();
-
-private:
-    QmlIR::Object *loadObject(const QV4::CompiledData::Object *serializedObject);
-
-    template <typename _Tp> _Tp *New() { return pool->New<_Tp>(); }
-
-    const QV4::CompiledData::Unit *unit;
-    QmlIR::Document *output;
-    QQmlJS::MemoryPool *pool;
-};
-
 } // namespace QmlIR
 
 struct QQmlCompileError
diff --git a/src/qml/compiler/qqmlirloader.cpp b/src/qml/compiler/qqmlirloader.cpp
new file mode 100644
index 0000000000..c2eb6da2fa
--- /dev/null
+++ b/src/qml/compiler/qqmlirloader.cpp
@@ -0,0 +1,205 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the tools applications of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qqmlirloader_p.h"
+#include <private/qqmlirbuilder_p.h>
+
+QT_BEGIN_NAMESPACE
+
+QQmlIRLoader::QQmlIRLoader(const QV4::CompiledData::Unit *qmlData, QmlIR::Document *output)
+    : unit(qmlData)
+      , output(output)
+{
+    pool = output->jsParserEngine.pool();
+}
+
+void QQmlIRLoader::load()
+{
+    output->jsGenerator.stringTable.initializeFromBackingUnit(unit);
+
+    const QV4::CompiledData::QmlUnit *qmlUnit = unit->qmlUnit();
+
+    for (quint32 i = 0; i < qmlUnit->nImports; ++i)
+        output->imports << qmlUnit->importAt(i);
+
+    if (unit->flags & QV4::CompiledData::Unit::IsSingleton) {
+        QmlIR::Pragma *p = New<QmlIR::Pragma>();
+        p->location = QV4::CompiledData::Location();
+        p->type = QmlIR::Pragma::PragmaSingleton;
+        output->pragmas << p;
+    }
+
+    for (uint i = 0; i < qmlUnit->nObjects; ++i) {
+        const QV4::CompiledData::Object *serializedObject = qmlUnit->objectAt(i);
+        QmlIR::Object *object = loadObject(serializedObject);
+        output->objects.append(object);
+    }
+}
+
+struct FakeExpression : public QQmlJS::AST::NullExpression
+{
+    FakeExpression(int start, int length)
+        : location(start, length)
+    {}
+
+    virtual QQmlJS::AST::SourceLocation firstSourceLocation() const
+    { return location; }
+
+    virtual QQmlJS::AST::SourceLocation lastSourceLocation() const
+    { return location; }
+
+private:
+    QQmlJS::AST::SourceLocation location;
+};
+
+QmlIR::Object *QQmlIRLoader::loadObject(const QV4::CompiledData::Object *serializedObject)
+{
+    QmlIR::Object *object = pool->New<QmlIR::Object>();
+    object->init(pool, serializedObject->inheritedTypeNameIndex, serializedObject->idNameIndex);
+
+    object->indexOfDefaultPropertyOrAlias = serializedObject->indexOfDefaultPropertyOrAlias;
+    object->defaultPropertyIsAlias = serializedObject->defaultPropertyIsAlias;
+    object->flags = serializedObject->flags;
+    object->id = serializedObject->id;
+    object->location = serializedObject->location;
+    object->locationOfIdProperty = serializedObject->locationOfIdProperty;
+
+    QVector<int> functionIndices;
+    functionIndices.reserve(serializedObject->nFunctions + serializedObject->nBindings / 2);
+
+    for (uint i = 0; i < serializedObject->nBindings; ++i) {
+        QmlIR::Binding *b = pool->New<QmlIR::Binding>();
+        *static_cast<QV4::CompiledData::Binding*>(b) = serializedObject->bindingTable()[i];
+        object->bindings->append(b);
+        if (b->type == QV4::CompiledData::Binding::Type_Script) {
+            functionIndices.append(b->value.compiledScriptIndex);
+            b->value.compiledScriptIndex = functionIndices.count() - 1;
+
+            QmlIR::CompiledFunctionOrExpression *foe = pool->New<QmlIR::CompiledFunctionOrExpression>();
+            foe->nameIndex = 0;
+
+            QQmlJS::AST::ExpressionNode *expr;
+
+            if (b->stringIndex != quint32(0)) {
+                const int start = output->code.length();
+                const QString script = output->stringAt(b->stringIndex);
+                const int length = script.length();
+                output->code.append(script);
+                expr = new (pool) FakeExpression(start, length);
+            } else
+                expr = new (pool) QQmlJS::AST::NullExpression();
+            foe->node = new (pool) QQmlJS::AST::ExpressionStatement(expr); // dummy
+            object->functionsAndExpressions->append(foe);
+        }
+    }
+
+    Q_ASSERT(object->functionsAndExpressions->count == functionIndices.count());
+
+    for (uint i = 0; i < serializedObject->nSignals; ++i) {
+        const QV4::CompiledData::Signal *serializedSignal = serializedObject->signalAt(i);
+        QmlIR::Signal *s = pool->New<QmlIR::Signal>();
+        s->nameIndex = serializedSignal->nameIndex;
+        s->location = serializedSignal->location;
+        s->parameters = pool->New<QmlIR::PoolList<QmlIR::SignalParameter> >();
+
+        for (uint i = 0; i < serializedSignal->nParameters; ++i) {
+            QmlIR::SignalParameter *p = pool->New<QmlIR::SignalParameter>();
+            *static_cast<QV4::CompiledData::Parameter*>(p) = *serializedSignal->parameterAt(i);
+            s->parameters->append(p);
+        }
+
+        object->qmlSignals->append(s);
+    }
+
+    for (uint i = 0; i < serializedObject->nEnums; ++i) {
+        const QV4::CompiledData::Enum *serializedEnum = serializedObject->enumAt(i);
+        QmlIR::Enum *e = pool->New<QmlIR::Enum>();
+        e->nameIndex = serializedEnum->nameIndex;
+        e->location = serializedEnum->location;
+        e->enumValues = pool->New<QmlIR::PoolList<QmlIR::EnumValue> >();
+
+        for (uint i = 0; i < serializedEnum->nEnumValues; ++i) {
+            QmlIR::EnumValue *v = pool->New<QmlIR::EnumValue>();
+            *static_cast<QV4::CompiledData::EnumValue*>(v) = *serializedEnum->enumValueAt(i);
+            e->enumValues->append(v);
+        }
+
+        object->qmlEnums->append(e);
+    }
+
+    const QV4::CompiledData::Property *serializedProperty = serializedObject->propertyTable();
+    for (uint i = 0; i < serializedObject->nProperties; ++i, ++serializedProperty) {
+        QmlIR::Property *p = pool->New<QmlIR::Property>();
+        *static_cast<QV4::CompiledData::Property*>(p) = *serializedProperty;
+        object->properties->append(p);
+    }
+
+    {
+        const QV4::CompiledData::Alias *serializedAlias = serializedObject->aliasTable();
+        for (uint i = 0; i < serializedObject->nAliases; ++i, ++serializedAlias) {
+            QmlIR::Alias *a = pool->New<QmlIR::Alias>();
+            *static_cast<QV4::CompiledData::Alias*>(a) = *serializedAlias;
+            object->aliases->append(a);
+        }
+    }
+
+    const quint32_le *functionIdx = serializedObject->functionOffsetTable();
+    for (uint i = 0; i < serializedObject->nFunctions; ++i, ++functionIdx) {
+        QmlIR::Function *f = pool->New<QmlIR::Function>();
+        const QV4::CompiledData::Function *compiledFunction = unit->functionAt(*functionIdx);
+
+        functionIndices.append(*functionIdx);
+        f->index = functionIndices.count() - 1;
+        f->location = compiledFunction->location;
+        f->nameIndex = compiledFunction->nameIndex;
+
+        f->formals.allocate(pool, int(compiledFunction->nFormals));
+        const quint32_le *formalNameIdx = compiledFunction->formalsTable();
+        for (uint i = 0; i < compiledFunction->nFormals; ++i, ++formalNameIdx)
+            f->formals[i] = *formalNameIdx;
+
+        object->functions->append(f);
+    }
+
+    object->runtimeFunctionIndices.allocate(pool, functionIndices);
+
+    return object;
+}
+
+QT_END_NAMESPACE
diff --git a/src/qml/compiler/qqmlirloader_p.h b/src/qml/compiler/qqmlirloader_p.h
new file mode 100644
index 0000000000..aa303c923f
--- /dev/null
+++ b/src/qml/compiler/qqmlirloader_p.h
@@ -0,0 +1,81 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the tools applications of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QQMLIRLOADER_P_H
+#define QQMLIRLOADER_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <private/qv4compileddata_p.h>
+#include <private/qqmljsmemorypool_p.h>
+
+QT_BEGIN_NAMESPACE
+
+namespace QmlIR {
+struct Document;
+struct Object;
+}
+
+struct Q_QML_PRIVATE_EXPORT QQmlIRLoader {
+    QQmlIRLoader(const QV4::CompiledData::Unit *unit, QmlIR::Document *output);
+
+    void load();
+
+private:
+    QmlIR::Object *loadObject(const QV4::CompiledData::Object *serializedObject);
+
+    template <typename _Tp> _Tp *New() { return pool->New<_Tp>(); }
+
+    const QV4::CompiledData::Unit *unit;
+    QmlIR::Document *output;
+    QQmlJS::MemoryPool *pool;
+};
+
+QT_END_NAMESPACE
+
+#endif // QQMLIRLOADER_P_H
diff --git a/src/qml/compiler/qqmlpropertycachecreator.cpp b/src/qml/compiler/qqmlpropertycachecreator.cpp
index fb54da5b73..bd4f2a0612 100644
--- a/src/qml/compiler/qqmlpropertycachecreator.cpp
+++ b/src/qml/compiler/qqmlpropertycachecreator.cpp
@@ -64,7 +64,9 @@ bool QQmlBindingInstantiationContext::resolveInstantiatingProperty()
     Q_ASSERT(instantiatingBinding->propertyNameIndex != 0);
 
     bool notInRevision = false;
-    instantiatingProperty = QmlIR::PropertyResolver(referencingObjectPropertyCache).property(instantiatingPropertyName, &notInRevision, QmlIR::PropertyResolver::IgnoreRevision);
+    instantiatingProperty = QQmlPropertyResolver(referencingObjectPropertyCache)
+                                    .property(instantiatingPropertyName, &notInRevision,
+                                              QQmlPropertyResolver::IgnoreRevision);
     return instantiatingProperty != nullptr;
 }
 
diff --git a/src/qml/compiler/qqmlpropertycachecreator_p.h b/src/qml/compiler/qqmlpropertycachecreator_p.h
index 346cfb5803..28eea27675 100644
--- a/src/qml/compiler/qqmlpropertycachecreator_p.h
+++ b/src/qml/compiler/qqmlpropertycachecreator_p.h
@@ -53,6 +53,7 @@
 #include <private/qqmlvaluetype_p.h>
 #include <private/qqmlengine_p.h>
 #include <private/qqmlmetaobject_p.h>
+#include <private/qqmlpropertyresolver_p.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -323,7 +324,7 @@ inline QQmlCompileError QQmlPropertyCacheCreator<ObjectContainer>::createMetaObj
 
     int varPropCount = 0;
 
-    QmlIR::PropertyResolver resolver(baseTypeCache);
+    QQmlPropertyResolver resolver(baseTypeCache);
 
     auto p = obj->propertiesBegin();
     auto pend = obj->propertiesEnd();
diff --git a/src/qml/compiler/qqmlpropertyresolver.cpp b/src/qml/compiler/qqmlpropertyresolver.cpp
new file mode 100644
index 0000000000..90eaca0b90
--- /dev/null
+++ b/src/qml/compiler/qqmlpropertyresolver.cpp
@@ -0,0 +1,92 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the tools applications of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qqmlpropertyresolver_p.h"
+
+QT_BEGIN_NAMESPACE
+
+QQmlPropertyData *QQmlPropertyResolver::property(const QString &name, bool *notInRevision,
+                                                 RevisionCheck check) const
+{
+    if (notInRevision) *notInRevision = false;
+
+    QQmlPropertyData *d = cache->property(name, nullptr, nullptr);
+
+    // Find the first property
+    while (d && d->isFunction())
+        d = cache->overrideData(d);
+
+    if (check != IgnoreRevision && d && !cache->isAllowedInRevision(d)) {
+        if (notInRevision) *notInRevision = true;
+        return nullptr;
+    } else {
+        return d;
+    }
+}
+
+
+QQmlPropertyData *QQmlPropertyResolver::signal(const QString &name, bool *notInRevision) const
+{
+    if (notInRevision) *notInRevision = false;
+
+    QQmlPropertyData *d = cache->property(name, nullptr, nullptr);
+    if (notInRevision) *notInRevision = false;
+
+    while (d && !(d->isFunction()))
+        d = cache->overrideData(d);
+
+    if (d && !cache->isAllowedInRevision(d)) {
+        if (notInRevision) *notInRevision = true;
+        return nullptr;
+    } else if (d && d->isSignal()) {
+        return d;
+    }
+
+    if (name.endsWith(QLatin1String("Changed"))) {
+        QString propName = name.mid(0, name.length() - static_cast<int>(strlen("Changed")));
+
+        d = property(propName, notInRevision);
+        if (d)
+            return cache->signal(d->notifyIndex());
+    }
+
+    return nullptr;
+}
+
+QT_END_NAMESPACE
diff --git a/src/qml/compiler/qqmlpropertyresolver_p.h b/src/qml/compiler/qqmlpropertyresolver_p.h
new file mode 100644
index 0000000000..df857f242e
--- /dev/null
+++ b/src/qml/compiler/qqmlpropertyresolver_p.h
@@ -0,0 +1,87 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the tools applications of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QQMLPROPERTYRESOLVER_P_H
+#define QQMLPROPERTYRESOLVER_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <private/qtqmlglobal_p.h>
+#include <private/qqmlpropertycache_p.h>
+#include <private/qqmlrefcount_p.h>
+
+QT_BEGIN_NAMESPACE
+
+struct Q_QML_EXPORT QQmlPropertyResolver
+{
+    QQmlPropertyResolver(const QQmlRefPointer<QQmlPropertyCache> &cache)
+        : cache(cache)
+    {}
+
+    QQmlPropertyData *property(int index) const
+    {
+        return cache->property(index);
+    }
+
+    enum RevisionCheck {
+        CheckRevision,
+        IgnoreRevision
+    };
+
+    QQmlPropertyData *property(const QString &name, bool *notInRevision = nullptr,
+                               RevisionCheck check = CheckRevision) const;
+
+    // This code must match the semantics of QQmlPropertyPrivate::findSignalByName
+    QQmlPropertyData *signal(const QString &name, bool *notInRevision) const;
+
+    QQmlRefPointer<QQmlPropertyCache> cache;
+};
+
+QT_END_NAMESPACE
+
+#endif // QQMLPROPERTYRESOLVER_P_H
diff --git a/src/qml/compiler/qqmlpropertyvalidator.cpp b/src/qml/compiler/qqmlpropertyvalidator.cpp
index 8c06760d42..71d5318652 100644
--- a/src/qml/compiler/qqmlpropertyvalidator.cpp
+++ b/src/qml/compiler/qqmlpropertyvalidator.cpp
@@ -41,11 +41,12 @@
 
 #include <private/qqmlcustomparser_p.h>
 #include <private/qqmlstringconverters_p.h>
+#include <private/qqmlpropertyresolver_p.h>
 #include <QtCore/qdatetime.h>
 
 QT_BEGIN_NAMESPACE
 
-QQmlPropertyValidator::QQmlPropertyValidator(QQmlEnginePrivate *enginePrivate, const QQmlImports &imports, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit)
+QQmlPropertyValidator::QQmlPropertyValidator(QQmlEnginePrivate *enginePrivate, const QQmlImports &imports, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit)
     : enginePrivate(enginePrivate)
     , compilationUnit(compilationUnit)
     , imports(imports)
@@ -121,7 +122,7 @@ QVector<QQmlCompileError> QQmlPropertyValidator::validateObject(int objectIndex,
         groupProperties.insert(pos, binding);
     }
 
-    QmlIR::PropertyResolver propertyResolver(propertyCache);
+    QQmlPropertyResolver propertyResolver(propertyCache);
 
     QString defaultPropertyName;
     QQmlPropertyData *defaultProperty = nullptr;
@@ -164,7 +165,7 @@ QVector<QQmlCompileError> QQmlPropertyValidator::validateObject(int objectIndex,
                 pd = propertyResolver.signal(name, &notInRevision);
             } else {
                 pd = propertyResolver.property(name, &notInRevision,
-                                               QmlIR::PropertyResolver::CheckRevision);
+                                               QQmlPropertyResolver::CheckRevision);
             }
 
             if (notInRevision) {
@@ -338,7 +339,7 @@ QQmlCompileError QQmlPropertyValidator::validateLiteralBinding(QQmlPropertyCache
         if (binding->flags & QV4::CompiledData::Binding::IsResolvedEnum)
             return noError;
 
-        QString value = binding->valueAsString(compilationUnit.data());
+        QString value = compilationUnit->bindingValueAsString(binding);
         QMetaProperty p = propertyCache->firstCppMetaObject()->property(property->coreIndex());
         bool ok;
         if (p.isFlagType()) {
@@ -396,7 +397,7 @@ QQmlCompileError QQmlPropertyValidator::validateLiteralBinding(QQmlPropertyCache
     break;
     case QVariant::UInt: {
         if (binding->type == QV4::CompiledData::Binding::Type_Number) {
-            double d = binding->valueAsNumber(compilationUnit->constants);
+            double d = compilationUnit->bindingValueAsNumber(binding);
             if (double(uint(d)) == d)
                 return noError;
         }
@@ -405,7 +406,7 @@ QQmlCompileError QQmlPropertyValidator::validateLiteralBinding(QQmlPropertyCache
     break;
     case QVariant::Int: {
         if (binding->type == QV4::CompiledData::Binding::Type_Number) {
-            double d = binding->valueAsNumber(compilationUnit->constants);
+            double d = compilationUnit->bindingValueAsNumber(binding);
             if (double(int(d)) == d)
                 return noError;
         }
@@ -426,7 +427,7 @@ QQmlCompileError QQmlPropertyValidator::validateLiteralBinding(QQmlPropertyCache
     break;
     case QVariant::Color: {
         bool ok = false;
-        QQmlStringConverters::rgbaFromString(binding->valueAsString(compilationUnit.data()), &ok);
+        QQmlStringConverters::rgbaFromString(compilationUnit->bindingValueAsString(binding), &ok);
         if (!ok) {
             return warnOrError(tr("Invalid property assignment: color expected"));
         }
@@ -435,7 +436,7 @@ QQmlCompileError QQmlPropertyValidator::validateLiteralBinding(QQmlPropertyCache
 #if QT_CONFIG(datestring)
     case QVariant::Date: {
         bool ok = false;
-        QQmlStringConverters::dateFromString(binding->valueAsString(compilationUnit.data()), &ok);
+        QQmlStringConverters::dateFromString(compilationUnit->bindingValueAsString(binding), &ok);
         if (!ok) {
             return warnOrError(tr("Invalid property assignment: date expected"));
         }
@@ -443,7 +444,7 @@ QQmlCompileError QQmlPropertyValidator::validateLiteralBinding(QQmlPropertyCache
     break;
     case QVariant::Time: {
         bool ok = false;
-        QQmlStringConverters::timeFromString(binding->valueAsString(compilationUnit.data()), &ok);
+        QQmlStringConverters::timeFromString(compilationUnit->bindingValueAsString(binding), &ok);
         if (!ok) {
             return warnOrError(tr("Invalid property assignment: time expected"));
         }
@@ -451,7 +452,7 @@ QQmlCompileError QQmlPropertyValidator::validateLiteralBinding(QQmlPropertyCache
     break;
     case QVariant::DateTime: {
         bool ok = false;
-        QQmlStringConverters::dateTimeFromString(binding->valueAsString(compilationUnit.data()), &ok);
+        QQmlStringConverters::dateTimeFromString(compilationUnit->bindingValueAsString(binding), &ok);
         if (!ok) {
             return warnOrError(tr("Invalid property assignment: datetime expected"));
         }
@@ -460,7 +461,7 @@ QQmlCompileError QQmlPropertyValidator::validateLiteralBinding(QQmlPropertyCache
 #endif // datestring
     case QVariant::Point: {
         bool ok = false;
-        QQmlStringConverters::pointFFromString(binding->valueAsString(compilationUnit.data()), &ok);
+        QQmlStringConverters::pointFFromString(compilationUnit->bindingValueAsString(binding), &ok);
         if (!ok) {
             return warnOrError(tr("Invalid property assignment: point expected"));
         }
@@ -468,7 +469,7 @@ QQmlCompileError QQmlPropertyValidator::validateLiteralBinding(QQmlPropertyCache
     break;
     case QVariant::PointF: {
         bool ok = false;
-        QQmlStringConverters::pointFFromString(binding->valueAsString(compilationUnit.data()), &ok);
+        QQmlStringConverters::pointFFromString(compilationUnit->bindingValueAsString(binding), &ok);
         if (!ok) {
             return warnOrError(tr("Invalid property assignment: point expected"));
         }
@@ -476,7 +477,7 @@ QQmlCompileError QQmlPropertyValidator::validateLiteralBinding(QQmlPropertyCache
     break;
     case QVariant::Size: {
         bool ok = false;
-        QQmlStringConverters::sizeFFromString(binding->valueAsString(compilationUnit.data()), &ok);
+        QQmlStringConverters::sizeFFromString(compilationUnit->bindingValueAsString(binding), &ok);
         if (!ok) {
             return warnOrError(tr("Invalid property assignment: size expected"));
         }
@@ -484,7 +485,7 @@ QQmlCompileError QQmlPropertyValidator::validateLiteralBinding(QQmlPropertyCache
     break;
     case QVariant::SizeF: {
         bool ok = false;
-        QQmlStringConverters::sizeFFromString(binding->valueAsString(compilationUnit.data()), &ok);
+        QQmlStringConverters::sizeFFromString(compilationUnit->bindingValueAsString(binding), &ok);
         if (!ok) {
             return warnOrError(tr("Invalid property assignment: size expected"));
         }
@@ -492,7 +493,7 @@ QQmlCompileError QQmlPropertyValidator::validateLiteralBinding(QQmlPropertyCache
     break;
     case QVariant::Rect: {
         bool ok = false;
-        QQmlStringConverters::rectFFromString(binding->valueAsString(compilationUnit.data()), &ok);
+        QQmlStringConverters::rectFFromString(compilationUnit->bindingValueAsString(binding), &ok);
         if (!ok) {
             return warnOrError(tr("Invalid property assignment: rect expected"));
         }
@@ -500,7 +501,7 @@ QQmlCompileError QQmlPropertyValidator::validateLiteralBinding(QQmlPropertyCache
     break;
     case QVariant::RectF: {
         bool ok = false;
-        QQmlStringConverters::rectFFromString(binding->valueAsString(compilationUnit.data()), &ok);
+        QQmlStringConverters::rectFFromString(compilationUnit->bindingValueAsString(binding), &ok);
         if (!ok) {
             return warnOrError(tr("Invalid property assignment: point expected"));
         }
@@ -517,7 +518,7 @@ QQmlCompileError QQmlPropertyValidator::validateLiteralBinding(QQmlPropertyCache
             float xp;
             float yp;
         } vec;
-        if (!QQmlStringConverters::createFromString(QMetaType::QVector2D, binding->valueAsString(compilationUnit.data()), &vec, sizeof(vec))) {
+        if (!QQmlStringConverters::createFromString(QMetaType::QVector2D, compilationUnit->bindingValueAsString(binding), &vec, sizeof(vec))) {
             return warnOrError(tr("Invalid property assignment: 2D vector expected"));
         }
     }
@@ -528,7 +529,7 @@ QQmlCompileError QQmlPropertyValidator::validateLiteralBinding(QQmlPropertyCache
             float yp;
             float zy;
         } vec;
-        if (!QQmlStringConverters::createFromString(QMetaType::QVector3D, binding->valueAsString(compilationUnit.data()), &vec, sizeof(vec))) {
+        if (!QQmlStringConverters::createFromString(QMetaType::QVector3D, compilationUnit->bindingValueAsString(binding), &vec, sizeof(vec))) {
             return warnOrError(tr("Invalid property assignment: 3D vector expected"));
         }
     }
@@ -540,7 +541,7 @@ QQmlCompileError QQmlPropertyValidator::validateLiteralBinding(QQmlPropertyCache
             float zy;
             float wp;
         } vec;
-        if (!QQmlStringConverters::createFromString(QMetaType::QVector4D, binding->valueAsString(compilationUnit.data()), &vec, sizeof(vec))) {
+        if (!QQmlStringConverters::createFromString(QMetaType::QVector4D, compilationUnit->bindingValueAsString(binding), &vec, sizeof(vec))) {
             return warnOrError(tr("Invalid property assignment: 4D vector expected"));
         }
     }
@@ -552,7 +553,7 @@ QQmlCompileError QQmlPropertyValidator::validateLiteralBinding(QQmlPropertyCache
             float yp;
             float zp;
         } vec;
-        if (!QQmlStringConverters::createFromString(QMetaType::QQuaternion, binding->valueAsString(compilationUnit.data()), &vec, sizeof(vec))) {
+        if (!QQmlStringConverters::createFromString(QMetaType::QQuaternion, compilationUnit->bindingValueAsString(binding), &vec, sizeof(vec))) {
             return warnOrError(tr("Invalid property assignment: quaternion expected"));
         }
     }
@@ -570,7 +571,7 @@ QQmlCompileError QQmlPropertyValidator::validateLiteralBinding(QQmlPropertyCache
         } else if (property->propType() == qMetaTypeId<QList<int> >()) {
             bool ok = (binding->type == QV4::CompiledData::Binding::Type_Number);
             if (ok) {
-                double n = binding->valueAsNumber(compilationUnit->constants);
+                double n = compilationUnit->bindingValueAsNumber(binding);
                 if (double(int(n)) != n)
                     ok = false;
             }
diff --git a/src/qml/compiler/qqmlpropertyvalidator_p.h b/src/qml/compiler/qqmlpropertyvalidator_p.h
index e9ae844ccb..8244b2df21 100644
--- a/src/qml/compiler/qqmlpropertyvalidator_p.h
+++ b/src/qml/compiler/qqmlpropertyvalidator_p.h
@@ -58,7 +58,7 @@ class QQmlPropertyValidator
 {
     Q_DECLARE_TR_FUNCTIONS(QQmlPropertyValidator)
 public:
-    QQmlPropertyValidator(QQmlEnginePrivate *enginePrivate, const QQmlImports &imports, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit);
+    QQmlPropertyValidator(QQmlEnginePrivate *enginePrivate, const QQmlImports &imports, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit);
 
     QVector<QQmlCompileError> validate();
 
@@ -72,13 +72,13 @@ private:
     Q_REQUIRED_RESULT QVector<QQmlCompileError> recordError(const QV4::CompiledData::Location &location, const QString &description) const;
     Q_REQUIRED_RESULT QVector<QQmlCompileError> recordError(const QQmlCompileError &error) const;
     QString stringAt(int index) const { return compilationUnit->stringAt(index); }
-    QV4::CompiledData::ResolvedTypeReference *resolvedType(int id) const
+    QV4::ResolvedTypeReference *resolvedType(int id) const
     {
         return compilationUnit->resolvedType(id);
     }
 
     QQmlEnginePrivate *enginePrivate;
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> compilationUnit;
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> compilationUnit;
     const QQmlImports &imports;
     const QV4::CompiledData::Unit *qmlUnit;
     const QQmlPropertyCacheVector &propertyCaches;
diff --git a/src/qml/compiler/qqmltypecompiler.cpp b/src/qml/compiler/qqmltypecompiler.cpp
index 239f04a58f..66320b8db9 100644
--- a/src/qml/compiler/qqmltypecompiler.cpp
+++ b/src/qml/compiler/qqmltypecompiler.cpp
@@ -44,6 +44,7 @@
 #include <private/qqmlcustomparser_p.h>
 #include <private/qqmlvmemetaobject_p.h>
 #include <private/qqmlcomponent_p.h>
+#include <private/qqmlpropertyresolver_p.h>
 
 #define COMPILE_EXCEPTION(token, desc) \
     { \
@@ -55,7 +56,7 @@ QT_BEGIN_NAMESPACE
 
 QQmlTypeCompiler::QQmlTypeCompiler(QQmlEnginePrivate *engine, QQmlTypeData *typeData,
                                    QmlIR::Document *parsedQML, const QQmlRefPointer<QQmlTypeNameCache> &typeNameCache,
-                                   QV4::CompiledData::ResolvedTypeReferenceMap *resolvedTypeCache, const QV4::CompiledData::DependentTypesHasher &dependencyHasher)
+                                   QV4::ResolvedTypeReferenceMap *resolvedTypeCache, const QV4::CompiledData::DependentTypesHasher &dependencyHasher)
     : resolvedTypes(resolvedTypeCache)
     , engine(engine)
     , typeData(typeData)
@@ -65,7 +66,7 @@ QQmlTypeCompiler::QQmlTypeCompiler(QQmlEnginePrivate *engine, QQmlTypeData *type
 {
 }
 
-QQmlRefPointer<QV4::CompiledData::CompilationUnit> QQmlTypeCompiler::compile()
+QQmlRefPointer<QV4::ExecutableCompilationUnit> QQmlTypeCompiler::compile()
 {
     // Build property caches and VME meta object data
 
@@ -133,7 +134,7 @@ QQmlRefPointer<QV4::CompiledData::CompilationUnit> QQmlTypeCompiler::compile()
             return nullptr;
     }
 
-    if (!document->javaScriptCompilationUnit) {
+    if (!document->javaScriptCompilationUnit.unitData()) {
         // Compile JS binding expressions and signal handlers if necessary
         {
             // We can compile script strings ahead of time, but they must be compiled
@@ -145,7 +146,7 @@ QQmlRefPointer<QV4::CompiledData::CompilationUnit> QQmlTypeCompiler::compile()
         document->jsModule.fileName = typeData->urlString();
         document->jsModule.finalUrl = typeData->finalUrlString();
         QmlIR::JSCodeGen v4CodeGenerator(document->code, &document->jsGenerator, &document->jsModule, &document->jsParserEngine,
-                                         document->program, &document->jsGenerator.stringTable, engine->v8engine()->illegalNames());
+                                         document->program, &document->jsGenerator.stringTable, engine->v4engine()->illegalNames());
         QQmlJSCodeGenerator jsCodeGen(this, &v4CodeGenerator);
         if (!jsCodeGen.generateCodeForComponents())
             return nullptr;
@@ -158,7 +159,9 @@ QQmlRefPointer<QV4::CompiledData::CompilationUnit> QQmlTypeCompiler::compile()
     QmlIR::QmlUnitGenerator qmlGenerator;
     qmlGenerator.generate(*document, dependencyHasher);
 
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> compilationUnit = document->javaScriptCompilationUnit;
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> compilationUnit
+            = QV4::ExecutableCompilationUnit::create(std::move(
+                    document->javaScriptCompilationUnit));
     compilationUnit->typeNameCache = typeNameCache;
     compilationUnit->resolvedTypes = *resolvedTypes;
     compilationUnit->propertyCaches = std::move(m_propertyCaches);
@@ -208,7 +211,7 @@ int QQmlTypeCompiler::registerConstant(QV4::ReturnedValue v)
 
 const QV4::CompiledData::Unit *QQmlTypeCompiler::qmlUnit() const
 {
-    return document->javaScriptCompilationUnit->unitData();
+    return document->javaScriptCompilationUnit.unitData();
 }
 
 const QQmlImports *QQmlTypeCompiler::imports() const
@@ -252,11 +255,6 @@ const QV4::Compiler::StringTableGenerator *QQmlTypeCompiler::stringPool() const
     return &document->jsGenerator.stringTable;
 }
 
-void QQmlTypeCompiler::setBindingPropertyDataPerObject(const QVector<QV4::CompiledData::BindingPropertyData> &propertyData)
-{
-    document->javaScriptCompilationUnit->bindingPropertyDataPerObject = propertyData;
-}
-
 QString QQmlTypeCompiler::bindingAsString(const QmlIR::Object *object, int scriptIndex) const
 {
     return object->bindingAsString(document, scriptIndex);
@@ -297,7 +295,7 @@ SignalHandlerConverter::SignalHandlerConverter(QQmlTypeCompiler *typeCompiler)
     , qmlObjects(*typeCompiler->qmlObjects())
     , imports(typeCompiler->imports())
     , customParsers(typeCompiler->customParserCache())
-    , illegalNames(typeCompiler->enginePrivate()->v8engine()->illegalNames())
+    , illegalNames(typeCompiler->enginePrivate()->v4engine()->illegalNames())
     , propertyCaches(typeCompiler->propertyCaches())
 {
 }
@@ -357,7 +355,7 @@ bool SignalHandlerConverter::convertSignalHandlerExpressionsToFunctionDeclaratio
         if (!QmlIR::IRBuilder::isSignalPropertyName(propertyName))
             continue;
 
-        QmlIR::PropertyResolver resolver(propertyCache);
+        QQmlPropertyResolver resolver(propertyCache);
 
         Q_ASSERT(propertyName.startsWith(QLatin1String("on")));
         propertyName.remove(0, 2);
@@ -513,7 +511,7 @@ bool QQmlEnumTypeResolver::resolveEnumBindings()
             continue;
         const QmlIR::Object *obj = qmlObjects.at(i);
 
-        QmlIR::PropertyResolver resolver(propertyCache);
+        QQmlPropertyResolver resolver(propertyCache);
 
         for (QmlIR::Binding *binding = obj->firstBinding(); binding; binding = binding->next) {
             if (binding->flags & QV4::CompiledData::Binding::IsSignalHandlerExpression
@@ -722,7 +720,7 @@ void QQmlAliasAnnotator::annotateBindingsToAliases()
 
         const QmlIR::Object *obj = qmlObjects.at(i);
 
-        QmlIR::PropertyResolver resolver(propertyCache);
+        QQmlPropertyResolver resolver(propertyCache);
         QQmlPropertyData *defaultProperty = obj->indexOfDefaultPropertyOrAlias != -1 ? propertyCache->parent()->defaultProperty() : propertyCache->defaultProperty();
 
         for (QmlIR::Binding *binding = obj->firstBinding(); binding; binding = binding->next) {
@@ -754,7 +752,7 @@ void QQmlScriptStringScanner::scan()
 
         const QmlIR::Object *obj = qmlObjects.at(i);
 
-        QmlIR::PropertyResolver resolver(propertyCache);
+        QQmlPropertyResolver resolver(propertyCache);
         QQmlPropertyData *defaultProperty = obj->indexOfDefaultPropertyOrAlias != -1 ? propertyCache->parent()->defaultProperty() : propertyCache->defaultProperty();
 
         for (QmlIR::Binding *binding = obj->firstBinding(); binding; binding = binding->next) {
@@ -799,7 +797,7 @@ static bool isUsableComponent(const QMetaObject *metaObject)
 
 void QQmlComponentAndAliasResolver::findAndRegisterImplicitComponents(const QmlIR::Object *obj, QQmlPropertyCache *propertyCache)
 {
-    QmlIR::PropertyResolver propertyResolver(propertyCache);
+    QQmlPropertyResolver propertyResolver(propertyCache);
 
     QQmlPropertyData *defaultProperty = obj->indexOfDefaultPropertyOrAlias != -1 ? propertyCache->parent()->defaultProperty() : propertyCache->defaultProperty();
 
@@ -856,7 +854,7 @@ void QQmlComponentAndAliasResolver::findAndRegisterImplicitComponents(const QmlI
         syntheticComponent->flags |= QV4::CompiledData::Object::IsComponent;
 
         if (!containsResolvedType(syntheticComponent->inheritedTypeNameIndex)) {
-            auto typeRef = new QV4::CompiledData::ResolvedTypeReference;
+            auto typeRef = new QV4::ResolvedTypeReference;
             typeRef->type = componentType;
             typeRef->majorVersion = componentType.majorVersion();
             typeRef->minorVersion = componentType.minorVersion();
@@ -1110,7 +1108,7 @@ QQmlComponentAndAliasResolver::AliasResolutionResult QQmlComponentAndAliasResolv
                 break;
             }
 
-            QmlIR::PropertyResolver resolver(targetCache);
+            QQmlPropertyResolver resolver(targetCache);
 
             QQmlPropertyData *targetProperty = resolver.property(property.toString());
 
@@ -1224,7 +1222,7 @@ bool QQmlDeferredAndCustomParserBindingScanner::scanObject(int objectIndex)
 
     QQmlCustomParser *customParser = customParsers.value(obj->inheritedTypeNameIndex);
 
-    QmlIR::PropertyResolver propertyResolver(propertyCache);
+    QQmlPropertyResolver propertyResolver(propertyCache);
 
     QStringList deferredPropertyNames;
     {
@@ -1263,7 +1261,8 @@ bool QQmlDeferredAndCustomParserBindingScanner::scanObject(int objectIndex)
                 continue;
 
             bool notInRevision = false;
-            pd = propertyResolver.property(name, &notInRevision, QmlIR::PropertyResolver::CheckRevision);
+            pd = propertyResolver.property(name, &notInRevision,
+                                           QQmlPropertyResolver::CheckRevision);
         }
 
         bool seenSubObjectWithId = false;
diff --git a/src/qml/compiler/qqmltypecompiler_p.h b/src/qml/compiler/qqmltypecompiler_p.h
index a49b97453f..f588909c42 100644
--- a/src/qml/compiler/qqmltypecompiler_p.h
+++ b/src/qml/compiler/qqmltypecompiler_p.h
@@ -81,7 +81,7 @@ struct QQmlTypeCompiler
 public:
     QQmlTypeCompiler(QQmlEnginePrivate *engine, QQmlTypeData *typeData, QmlIR::Document *document,
                      const QQmlRefPointer<QQmlTypeNameCache> &typeNameCache,
-                     QV4::CompiledData::ResolvedTypeReferenceMap *resolvedTypeCache,
+                     QV4::ResolvedTypeReferenceMap *resolvedTypeCache,
                      const QV4::CompiledData::DependentTypesHasher &dependencyHasher);
 
     // --- interface used by QQmlPropertyCacheCreator
@@ -91,10 +91,10 @@ public:
     QString stringAt(int idx) const;
     QmlIR::PoolList<QmlIR::Function>::Iterator objectFunctionsBegin(const QmlIR::Object *object) const { return object->functionsBegin(); }
     QmlIR::PoolList<QmlIR::Function>::Iterator objectFunctionsEnd(const QmlIR::Object *object) const { return object->functionsEnd(); }
-    QV4::CompiledData::ResolvedTypeReferenceMap *resolvedTypes = nullptr;
+    QV4::ResolvedTypeReferenceMap *resolvedTypes = nullptr;
     // ---
 
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> compile();
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> compile();
 
     QList<QQmlError> compilationErrors() const { return errors; }
     void recordError(QQmlError error);
@@ -118,7 +118,6 @@ public:
     QQmlJS::MemoryPool *memoryPool();
     QStringRef newStringRef(const QString &string);
     const QV4::Compiler::StringTableGenerator *stringPool() const;
-    void setBindingPropertyDataPerObject(const QVector<QV4::CompiledData::BindingPropertyData> &propertyData);
 
     const QHash<int, QQmlCustomParser*> &customParserCache() const { return customParsers; }
 
@@ -126,7 +125,7 @@ public:
 
     void addImport(const QString &module, const QString &qualifier, int majorVersion, int minorVersion);
 
-    QV4::CompiledData::ResolvedTypeReference *resolvedType(int id) const
+    QV4::ResolvedTypeReference *resolvedType(int id) const
     {
         return resolvedTypes->value(id);
     }
@@ -157,12 +156,12 @@ protected:
     void recordError(const QQmlCompileError &error)
     { compiler->recordError(error); }
 
-    QV4::CompiledData::ResolvedTypeReference *resolvedType(int id) const
+    QV4::ResolvedTypeReference *resolvedType(int id) const
     { return compiler->resolvedType(id); }
     bool containsResolvedType(int id) const
     { return compiler->resolvedTypes->contains(id); }
-    QV4::CompiledData::ResolvedTypeReferenceMap::iterator insertResolvedType(
-            int id, QV4::CompiledData::ResolvedTypeReference *value)
+    QV4::ResolvedTypeReferenceMap::iterator insertResolvedType(
+            int id, QV4::ResolvedTypeReference *value)
     { return compiler->resolvedTypes->insert(id, value); }
 
     QQmlTypeCompiler *compiler;
diff --git a/src/qml/compiler/qv4codegen.cpp b/src/qml/compiler/qv4codegen.cpp
index 1bf0e7147d..b145ceb51e 100644
--- a/src/qml/compiler/qv4codegen.cpp
+++ b/src/qml/compiler/qv4codegen.cpp
@@ -45,16 +45,15 @@
 #include <QtCore/QStack>
 #include <QScopeGuard>
 #include <private/qqmljsast_p.h>
-#include <private/qv4string_p.h>
+#include <private/qqmljslexer_p.h>
+#include <private/qqmljsparser_p.h>
+#include <private/qv4stringtoarrayindex_p.h>
 #include <private/qv4value_p.h>
 #include <private/qv4compilercontext_p.h>
 #include <private/qv4compilercontrolflow_p.h>
 #include <private/qv4bytecodegenerator_p.h>
 #include <private/qv4compilerscanfunctions_p.h>
-
-#ifndef V4_BOOTSTRAP
-#  include <qqmlerror.h>
-#endif
+#include <qqmlerror.h>
 
 #include <cmath>
 #include <iostream>
@@ -1243,7 +1242,7 @@ bool Codegen::visit(ArrayMemberExpression *ast)
         return false;
     if (AST::StringLiteral *str = AST::cast<AST::StringLiteral *>(ast->expression)) {
         QString s = str->value.toString();
-        uint arrayIndex = QV4::String::toArrayIndex(s);
+        uint arrayIndex = stringToArrayIndex(s);
         if (arrayIndex == UINT_MAX) {
             setExprResult(Reference::fromMember(base, str->value.toString()));
             return false;
@@ -2513,7 +2512,7 @@ bool Codegen::visit(ObjectPattern *ast)
         if (cname || p->type != PatternProperty::Literal)
             break;
         QString name = p->name->asString();
-        uint arrayIndex = QV4::String::toArrayIndex(name);
+        uint arrayIndex = stringToArrayIndex(name);
         if (arrayIndex != UINT_MAX)
             break;
         if (members.contains(name))
@@ -3781,23 +3780,54 @@ QList<QQmlJS::DiagnosticMessage> Codegen::errors() const
     return _errors;
 }
 
-QQmlRefPointer<CompiledData::CompilationUnit> Codegen::generateCompilationUnit(bool generateUnitData)
+QV4::CompiledData::CompilationUnit Codegen::generateCompilationUnit(
+        bool generateUnitData)
 {
-    CompiledData::Unit *unitData = nullptr;
-    if (generateUnitData)
-        unitData = jsUnitGenerator->generateUnit();
-    CompiledData::CompilationUnit *compilationUnit = new CompiledData::CompilationUnit(unitData);
-
-    QQmlRefPointer<CompiledData::CompilationUnit> unit;
-    unit.adopt(compilationUnit);
-    return unit;
+    return QV4::CompiledData::CompilationUnit(
+            generateUnitData ? jsUnitGenerator->generateUnit() : nullptr);
 }
 
-QQmlRefPointer<CompiledData::CompilationUnit> Codegen::createUnitForLoading()
+CompiledData::CompilationUnit Codegen::compileModule(
+        bool debugMode, const QString &url, const QString &sourceCode,
+        const QDateTime &sourceTimeStamp, QList<QQmlJS::DiagnosticMessage> *diagnostics)
 {
-    QQmlRefPointer<CompiledData::CompilationUnit> result;
-    result.adopt(new CompiledData::CompilationUnit);
-    return result;
+    QQmlJS::Engine ee;
+    QQmlJS::Lexer lexer(&ee);
+    lexer.setCode(sourceCode, /*line*/1, /*qml mode*/false);
+    QQmlJS::Parser parser(&ee);
+
+    const bool parsed = parser.parseModule();
+
+    if (diagnostics)
+        *diagnostics = parser.diagnosticMessages();
+
+    if (!parsed)
+        return CompiledData::CompilationUnit();
+
+    QQmlJS::AST::ESModule *moduleNode = QQmlJS::AST::cast<QQmlJS::AST::ESModule*>(parser.rootNode());
+    if (!moduleNode) {
+        // if parsing was successful, and we have no module, then
+        // the file was empty.
+        if (diagnostics)
+            diagnostics->clear();
+        return nullptr;
+    }
+
+    using namespace QV4::Compiler;
+    Compiler::Module compilerModule(debugMode);
+    compilerModule.unitFlags |= CompiledData::Unit::IsESModule;
+    compilerModule.sourceTimeStamp = sourceTimeStamp;
+    JSUnitGenerator jsGenerator(&compilerModule);
+    Codegen cg(&jsGenerator, /*strictMode*/true);
+    cg.generateFromModule(url, url, sourceCode, moduleNode, &compilerModule);
+    auto errors = cg.errors();
+    if (diagnostics)
+        *diagnostics << errors;
+
+    if (!errors.isEmpty())
+        return CompiledData::CompilationUnit();
+
+    return cg.generateCompilationUnit();
 }
 
 class Codegen::VolatileMemoryLocationScanner: protected QQmlJS::AST::Visitor
@@ -3914,8 +3944,6 @@ Codegen::VolatileMemoryLocations Codegen::scanVolatileMemoryLocations(AST::Node
 }
 
 
-#ifndef V4_BOOTSTRAP
-
 QList<QQmlError> Codegen::qmlErrors() const
 {
     QList<QQmlError> qmlErrors;
@@ -3939,8 +3967,6 @@ QList<QQmlError> Codegen::qmlErrors() const
     return qmlErrors;
 }
 
-#endif // V4_BOOTSTRAP
-
 bool Codegen::RValue::operator==(const RValue &other) const
 {
     switch (type) {
diff --git a/src/qml/compiler/qv4codegen_p.h b/src/qml/compiler/qv4codegen_p.h
index ad86483132..e519da0142 100644
--- a/src/qml/compiler/qv4codegen_p.h
+++ b/src/qml/compiler/qv4codegen_p.h
@@ -52,12 +52,15 @@
 
 #include "private/qv4global_p.h"
 #include <private/qqmljsastvisitor_p.h>
+#include <private/qqmljsengine_p.h>
 #include <private/qqmljsast_p.h>
 #include <private/qv4compiler_p.h>
 #include <private/qv4compilercontext_p.h>
 #include <private/qv4util_p.h>
 #include <private/qv4bytecodegenerator_p.h>
-#include <private/qv4stackframe_p.h>
+#include <private/qv4calldata_p.h>
+
+#include <QtQml/qqmlerror.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -659,9 +662,7 @@ protected:
 
 public:
     QList<DiagnosticMessage> errors() const;
-#ifndef V4_BOOTSTRAP
     QList<QQmlError> qmlErrors() const;
-#endif
 
     Reference binopHelper(QSOperator::Op oper, Reference &left, Reference &right);
     Reference jumpBinop(QSOperator::Op oper, Reference &left, Reference &right);
@@ -681,8 +682,10 @@ public:
 
     Reference referenceForName(const QString &name, bool lhs, const QQmlJS::AST::SourceLocation &accessLocation = QQmlJS::AST::SourceLocation());
 
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> generateCompilationUnit(bool generateUnitData = true);
-    static QQmlRefPointer<QV4::CompiledData::CompilationUnit> createUnitForLoading();
+    QV4::CompiledData::CompilationUnit generateCompilationUnit(bool generateUnitData = true);
+    static QV4::CompiledData::CompilationUnit compileModule(
+            bool debugMode, const QString &url, const QString &sourceCode,
+            const QDateTime &sourceTimeStamp, QList<DiagnosticMessage> *diagnostics);
 
     Context *currentContext() const { return _context; }
     BytecodeGenerator *generator() const { return bytecodeGenerator; }
diff --git a/src/qml/compiler/qv4compileddata.cpp b/src/qml/compiler/qv4compileddata.cpp
index a78094f17c..0fed0a03b2 100644
--- a/src/qml/compiler/qv4compileddata.cpp
+++ b/src/qml/compiler/qv4compileddata.cpp
@@ -39,34 +39,12 @@
 
 #include "qv4compileddata_p.h"
 #include <private/qv4value_p.h>
-#ifndef V4_BOOTSTRAP
-#include <private/qv4engine_p.h>
-#include <private/qv4function_p.h>
-#include <private/qv4objectproto_p.h>
-#include <private/qv4lookup_p.h>
-#include <private/qv4regexpobject_p.h>
-#include <private/qv4regexp_p.h>
-#include <private/qqmltypeloader_p.h>
-#include <private/qqmlengine_p.h>
-#include <private/qv4vme_moth_p.h>
-#include <private/qv4module_p.h>
-#include <private/qv4qobjectwrapper_p.h>
-#include <private/qqmlvaluetypewrapper_p.h>
-#include "qv4compilationunitmapper_p.h"
-#include <QQmlPropertyMap>
-#include <QDateTime>
-#include <QFile>
-#include <QFileInfo>
-#include <QScopedValueRollback>
-#include <QStandardPaths>
-#include <QDir>
-#include <private/qv4identifiertable_p.h>
-#endif
 #include <private/qqmlirbuilder_p.h>
 #include <QCoreApplication>
 #include <QCryptographicHash>
 #include <QSaveFile>
 #include <QScopeGuard>
+#include <QFileInfo>
 
 // generated by qmake:
 #include "qml_compile_hash_p.h"
@@ -99,23 +77,13 @@ CompilationUnit::CompilationUnit(const Unit *unitData, const QString &fileName,
 
 CompilationUnit::~CompilationUnit()
 {
-#ifndef V4_BOOTSTRAP
-    unlink();
-#endif
-
     if (data) {
         if (data->qmlUnit() != qmlData)
             free(const_cast<QmlUnit *>(qmlData));
         qmlData = nullptr;
 
-#ifndef V4_BOOTSTRAP
         if (!(data->flags & QV4::CompiledData::Unit::StaticData))
             free(const_cast<Unit *>(data));
-#else
-        // Unconditionally free the memory. In the dev tools we create units that have
-        // the flag set and will be saved to disk, so intended to persist later.
-        free(const_cast<Unit *>(data));
-#endif
     }
     data = nullptr;
 #if Q_BYTE_ORDER == Q_BIG_ENDIAN
@@ -126,585 +94,11 @@ CompilationUnit::~CompilationUnit()
     delete [] imports;
     imports = nullptr;
 }
-#ifndef V4_BOOTSTRAP
-
-QString CompilationUnit::localCacheFilePath(const QUrl &url)
-{
-    const QString localSourcePath = QQmlFile::urlToLocalFileOrQrc(url);
-    const QString cacheFileSuffix = QFileInfo(localSourcePath + QLatin1Char('c')).completeSuffix();
-    QCryptographicHash fileNameHash(QCryptographicHash::Sha1);
-    fileNameHash.addData(localSourcePath.toUtf8());
-    QString directory = QStandardPaths::writableLocation(QStandardPaths::CacheLocation) + QLatin1String("/qmlcache/");
-    QDir::root().mkpath(directory);
-    return directory + QString::fromUtf8(fileNameHash.result().toHex()) + QLatin1Char('.') + cacheFileSuffix;
-}
-
-QV4::Function *CompilationUnit::linkToEngine(ExecutionEngine *engine)
-{
-    this->engine = engine;
-    engine->compilationUnits.insert(this);
-
-    Q_ASSERT(!runtimeStrings);
-    Q_ASSERT(data);
-    const quint32 stringCount = totalStringCount();
-    runtimeStrings = (QV4::Heap::String **)malloc(stringCount * sizeof(QV4::Heap::String*));
-    // memset the strings to 0 in case a GC run happens while we're within the loop below
-    memset(runtimeStrings, 0, stringCount * sizeof(QV4::Heap::String*));
-    for (uint i = 0; i < stringCount; ++i)
-        runtimeStrings[i] = engine->newString(stringAt(i));
-
-    runtimeRegularExpressions = new QV4::Value[data->regexpTableSize];
-    // memset the regexps to 0 in case a GC run happens while we're within the loop below
-    memset(runtimeRegularExpressions, 0, data->regexpTableSize * sizeof(QV4::Value));
-    for (uint i = 0; i < data->regexpTableSize; ++i) {
-        const CompiledData::RegExp *re = data->regexpAt(i);
-        uint f = re->flags;
-        const CompiledData::RegExp::Flags flags = static_cast<CompiledData::RegExp::Flags>(f);
-        runtimeRegularExpressions[i] = QV4::RegExp::create(engine, stringAt(re->stringIndex), flags);
-    }
-
-    if (data->lookupTableSize) {
-        runtimeLookups = new QV4::Lookup[data->lookupTableSize];
-        memset(runtimeLookups, 0, data->lookupTableSize * sizeof(QV4::Lookup));
-        const CompiledData::Lookup *compiledLookups = data->lookupTable();
-        for (uint i = 0; i < data->lookupTableSize; ++i) {
-            QV4::Lookup *l = runtimeLookups + i;
-
-            Lookup::Type type = Lookup::Type(uint(compiledLookups[i].type_and_flags));
-            if (type == CompiledData::Lookup::Type_Getter)
-                l->getter = QV4::Lookup::getterGeneric;
-            else if (type == CompiledData::Lookup::Type_Setter)
-                l->setter = QV4::Lookup::setterGeneric;
-            else if (type == CompiledData::Lookup::Type_GlobalGetter)
-                l->globalGetter = QV4::Lookup::globalGetterGeneric;
-            else if (type == CompiledData::Lookup::Type_QmlContextPropertyGetter)
-                l->qmlContextPropertyGetter = QQmlContextWrapper::resolveQmlContextPropertyLookupGetter;
-            l->nameIndex = compiledLookups[i].nameIndex;
-        }
-    }
-
-    if (data->jsClassTableSize) {
-        runtimeClasses = (QV4::Heap::InternalClass **)malloc(data->jsClassTableSize * sizeof(QV4::Heap::InternalClass *));
-        // memset the regexps to 0 in case a GC run happens while we're within the loop below
-        memset(runtimeClasses, 0, data->jsClassTableSize * sizeof(QV4::Heap::InternalClass *));
-        for (uint i = 0; i < data->jsClassTableSize; ++i) {
-            int memberCount = 0;
-            const CompiledData::JSClassMember *member = data->jsClassAt(i, &memberCount);
-            runtimeClasses[i] = engine->internalClasses(QV4::ExecutionEngine::Class_Object);
-            for (int j = 0; j < memberCount; ++j, ++member)
-                runtimeClasses[i] = runtimeClasses[i]->addMember(engine->identifierTable->asPropertyKey(runtimeStrings[member->nameOffset]), member->isAccessor ? QV4::Attr_Accessor : QV4::Attr_Data);
-        }
-    }
-
-    runtimeFunctions.resize(data->functionTableSize);
-    for (int i = 0 ;i < runtimeFunctions.size(); ++i) {
-        const QV4::CompiledData::Function *compiledFunction = data->functionAt(i);
-        runtimeFunctions[i] = QV4::Function::create(engine, this, compiledFunction);
-    }
-
-    Scope scope(engine);
-    Scoped<InternalClass> ic(scope);
-
-    runtimeBlocks.resize(data->blockTableSize);
-    for (int i = 0 ;i < runtimeBlocks.size(); ++i) {
-        const QV4::CompiledData::Block *compiledBlock = data->blockAt(i);
-        ic = engine->internalClasses(EngineBase::Class_CallContext);
-
-        // first locals
-        const quint32_le *localsIndices = compiledBlock->localsTable();
-        for (quint32 j = 0; j < compiledBlock->nLocals; ++j)
-            ic = ic->addMember(engine->identifierTable->asPropertyKey(runtimeStrings[localsIndices[j]]), Attr_NotConfigurable);
-        runtimeBlocks[i] = ic->d();
-    }
-
-    static const bool showCode = qEnvironmentVariableIsSet("QV4_SHOW_BYTECODE");
-    if (showCode) {
-        qDebug() << "=== Constant table";
-        Moth::dumpConstantTable(constants, data->constantTableSize);
-        qDebug() << "=== String table";
-        for (uint i = 0, end = totalStringCount(); i < end; ++i)
-            qDebug() << "    " << i << ":" << runtimeStrings[i]->toQString();
-        qDebug() << "=== Closure table";
-        for (uint i = 0; i < data->functionTableSize; ++i)
-            qDebug() << "    " << i << ":" << runtimeFunctions[i]->name()->toQString();
-        qDebug() << "root function at index " << (data->indexOfRootFunction != -1 ? data->indexOfRootFunction : 0);
-    }
-
-    if (data->indexOfRootFunction != -1)
-        return runtimeFunctions[data->indexOfRootFunction];
-    else
-        return nullptr;
-}
-
-Heap::Object *CompilationUnit::templateObjectAt(int index) const
-{
-    Q_ASSERT(index < int(data->templateObjectTableSize));
-    if (!templateObjects.size())
-        templateObjects.resize(data->templateObjectTableSize);
-    Heap::Object *o = templateObjects.at(index);
-    if (o)
-        return o;
-
-    // create the template object
-    Scope scope(engine);
-    const CompiledData::TemplateObject *t = data->templateObjectAt(index);
-    Scoped<ArrayObject> a(scope, engine->newArrayObject(t->size));
-    Scoped<ArrayObject> raw(scope, engine->newArrayObject(t->size));
-    ScopedValue s(scope);
-    for (uint i = 0; i < t->size; ++i) {
-        s = runtimeStrings[t->stringIndexAt(i)];
-        a->arraySet(i, s);
-        s = runtimeStrings[t->rawStringIndexAt(i)];
-        raw->arraySet(i, s);
-    }
-
-    ObjectPrototype::method_freeze(engine->functionCtor(), nullptr, raw, 1);
-    a->defineReadonlyProperty(QStringLiteral("raw"), raw);
-    ObjectPrototype::method_freeze(engine->functionCtor(), nullptr, a, 1);
-
-    templateObjects[index] = a->objectValue()->d();
-    return templateObjects.at(index);
-}
-
-void CompilationUnit::unlink()
-{
-    if (engine)
-        nextCompilationUnit.remove();
-
-    if (isRegisteredWithEngine) {
-        Q_ASSERT(data && propertyCaches.count() > 0 && propertyCaches.at(/*root object*/0));
-        if (qmlEngine)
-            qmlEngine->unregisterInternalCompositeType(this);
-        QQmlMetaType::unregisterInternalCompositeType(this);
-        isRegisteredWithEngine = false;
-    }
-
-    propertyCaches.clear();
-
-    if (runtimeLookups) {
-        for (uint i = 0; i < data->lookupTableSize; ++i) {
-            QV4::Lookup &l = runtimeLookups[i];
-            if (l.getter == QV4::QObjectWrapper::lookupGetter) {
-                if (QQmlPropertyCache *pc = l.qobjectLookup.propertyCache)
-                    pc->release();
-            } else if (l.getter == QQmlValueTypeWrapper::lookupGetter) {
-                if (QQmlPropertyCache *pc = l.qgadgetLookup.propertyCache)
-                    pc->release();
-            }
-
-            if (l.qmlContextPropertyGetter == QQmlContextWrapper::lookupScopeObjectProperty) {
-                if (QQmlPropertyCache *pc = l.qobjectLookup.propertyCache)
-                    pc->release();
-            }
-        }
-    }
-
-    dependentScripts.clear();
-
-    typeNameCache = nullptr;
-
-    qDeleteAll(resolvedTypes);
-    resolvedTypes.clear();
-
-    engine = nullptr;
-    qmlEngine = nullptr;
-    free(runtimeStrings);
-    runtimeStrings = nullptr;
-    delete [] runtimeLookups;
-    runtimeLookups = nullptr;
-    delete [] runtimeRegularExpressions;
-    runtimeRegularExpressions = nullptr;
-    free(runtimeClasses);
-    runtimeClasses = nullptr;
-    for (QV4::Function *f : qAsConst(runtimeFunctions))
-        f->destroy();
-    runtimeFunctions.clear();
-}
 
-void CompilationUnit::markObjects(QV4::MarkStack *markStack)
-{
-    if (runtimeStrings) {
-        for (uint i = 0, end = totalStringCount(); i < end; ++i)
-            if (runtimeStrings[i])
-                runtimeStrings[i]->mark(markStack);
-    }
-    if (runtimeRegularExpressions) {
-        for (uint i = 0; i < data->regexpTableSize; ++i)
-            runtimeRegularExpressions[i].mark(markStack);
-    }
-    if (runtimeClasses) {
-        for (uint i = 0; i < data->jsClassTableSize; ++i)
-            if (runtimeClasses[i])
-                runtimeClasses[i]->mark(markStack);
-    }
-    for (QV4::Function *f : qAsConst(runtimeFunctions))
-        if (f && f->internalClass)
-            f->internalClass->mark(markStack);
-    for (QV4::Heap::InternalClass *c : qAsConst(runtimeBlocks))
-        if (c)
-            c->mark(markStack);
-
-    for (QV4::Heap::Object *o : qAsConst(templateObjects))
-        if (o)
-            o->mark(markStack);
-
-    if (runtimeLookups) {
-        for (uint i = 0; i < data->lookupTableSize; ++i)
-            runtimeLookups[i].markObjects(markStack);
-    }
-
-    if (m_module)
-        m_module->mark(markStack);
-}
-
-IdentifierHash CompilationUnit::createNamedObjectsPerComponent(int componentObjectIndex)
-{
-    IdentifierHash namedObjectCache(engine);
-    const CompiledData::Object *component = objectAt(componentObjectIndex);
-    const quint32_le *namedObjectIndexPtr = component->namedObjectsInComponentTable();
-    for (quint32 i = 0; i < component->nNamedObjectsInComponent; ++i, ++namedObjectIndexPtr) {
-        const CompiledData::Object *namedObject = objectAt(*namedObjectIndexPtr);
-        namedObjectCache.add(runtimeStrings[namedObject->idNameIndex], namedObject->id);
-    }
-    return *namedObjectsPerComponentCache.insert(componentObjectIndex, namedObjectCache);
-}
-
-void CompilationUnit::finalizeCompositeType(QQmlEnginePrivate *qmlEngine)
-{
-    this->qmlEngine = qmlEngine;
-
-    // Add to type registry of composites
-    if (propertyCaches.needsVMEMetaObject(/*root object*/0)) {
-        QQmlMetaType::registerInternalCompositeType(this);
-        qmlEngine->registerInternalCompositeType(this);
-    } else {
-        const QV4::CompiledData::Object *obj = objectAt(/*root object*/0);
-        auto *typeRef = resolvedTypes.value(obj->inheritedTypeNameIndex);
-        Q_ASSERT(typeRef);
-        if (typeRef->compilationUnit) {
-            metaTypeId = typeRef->compilationUnit->metaTypeId;
-            listMetaTypeId = typeRef->compilationUnit->listMetaTypeId;
-        } else {
-            metaTypeId = typeRef->type.typeId();
-            listMetaTypeId = typeRef->type.qListTypeId();
-        }
-    }
-
-    // Collect some data for instantiation later.
-    int bindingCount = 0;
-    int parserStatusCount = 0;
-    int objectCount = 0;
-    for (quint32 i = 0, count = this->objectCount(); i < count; ++i) {
-        const QV4::CompiledData::Object *obj = objectAt(i);
-        bindingCount += obj->nBindings;
-        if (auto *typeRef = resolvedTypes.value(obj->inheritedTypeNameIndex)) {
-            if (typeRef->type.isValid()) {
-                if (typeRef->type.parserStatusCast() != -1)
-                    ++parserStatusCount;
-            }
-            ++objectCount;
-            if (typeRef->compilationUnit) {
-                bindingCount += typeRef->compilationUnit->totalBindingsCount;
-                parserStatusCount += typeRef->compilationUnit->totalParserStatusCount;
-                objectCount += typeRef->compilationUnit->totalObjectCount;
-            }
-        }
-    }
-
-    totalBindingsCount = bindingCount;
-    totalParserStatusCount = parserStatusCount;
-    totalObjectCount = objectCount;
-}
-
-bool CompilationUnit::verifyChecksum(const DependentTypesHasher &dependencyHasher) const
-{
-    if (!dependencyHasher) {
-        for (size_t i = 0; i < sizeof(data->dependencyMD5Checksum); ++i) {
-            if (data->dependencyMD5Checksum[i] != 0)
-                return false;
-        }
-        return true;
-    }
-    QCryptographicHash hash(QCryptographicHash::Md5);
-    if (!dependencyHasher(&hash))
-        return false;
-    QByteArray checksum = hash.result();
-    Q_ASSERT(checksum.size() == sizeof(data->dependencyMD5Checksum));
-    return memcmp(data->dependencyMD5Checksum, checksum.constData(),
-                  sizeof(data->dependencyMD5Checksum)) == 0;
-}
-
-QStringList CompilationUnit::moduleRequests() const
-{
-    QStringList requests;
-    requests.reserve(data->moduleRequestTableSize);
-    for (uint i = 0; i < data->moduleRequestTableSize; ++i)
-        requests << stringAt(data->moduleRequestTable()[i]);
-    return requests;
-}
-
-Heap::Module *CompilationUnit::instantiate(ExecutionEngine *engine)
-{
-    if (isESModule() && m_module)
-        return m_module;
-
-    if (data->indexOfRootFunction < 0)
-        return nullptr;
-
-    if (!this->engine)
-        linkToEngine(engine);
-
-    Scope scope(engine);
-    Scoped<Module> module(scope, engine->memoryManager->allocate<Module>(engine, this));
-
-    if (isESModule())
-        m_module = module->d();
-
-    for (const QString &request: moduleRequests()) {
-        auto dependentModuleUnit = engine->loadModule(QUrl(request), this);
-        if (engine->hasException)
-            return nullptr;
-        dependentModuleUnit->instantiate(engine);
-    }
-
-    ScopedString importName(scope);
-
-    const uint importCount = data->importEntryTableSize;
-    if (importCount > 0) {
-        imports = new const Value *[importCount];
-        memset(imports, 0, importCount * sizeof(Value *));
-    }
-    for (uint i = 0; i < importCount; ++i) {
-        const CompiledData::ImportEntry &entry = data->importEntryTable()[i];
-        auto dependentModuleUnit = engine->loadModule(QUrl(stringAt(entry.moduleRequest)), this);
-        importName = runtimeStrings[entry.importName];
-        const Value *valuePtr = dependentModuleUnit->resolveExport(importName);
-        if (!valuePtr) {
-            QString referenceErrorMessage = QStringLiteral("Unable to resolve import reference ");
-            referenceErrorMessage += importName->toQString();
-            engine->throwReferenceError(referenceErrorMessage, fileName(), entry.location.line, entry.location.column);
-            return nullptr;
-        }
-        imports[i] = valuePtr;
-    }
-
-    for (uint i = 0; i < data->indirectExportEntryTableSize; ++i) {
-        const CompiledData::ExportEntry &entry = data->indirectExportEntryTable()[i];
-        auto dependentModuleUnit = engine->loadModule(QUrl(stringAt(entry.moduleRequest)), this);
-        if (!dependentModuleUnit)
-            return nullptr;
-
-        ScopedString importName(scope, runtimeStrings[entry.importName]);
-        if (!dependentModuleUnit->resolveExport(importName)) {
-            QString referenceErrorMessage = QStringLiteral("Unable to resolve re-export reference ");
-            referenceErrorMessage += importName->toQString();
-            engine->throwReferenceError(referenceErrorMessage, fileName(), entry.location.line, entry.location.column);
-            return nullptr;
-        }
-    }
-
-    return module->d();
-}
-
-const Value *CompilationUnit::resolveExport(QV4::String *exportName)
-{
-    QVector<ResolveSetEntry> resolveSet;
-    return resolveExportRecursively(exportName, &resolveSet);
-}
-
-QStringList CompilationUnit::exportedNames() const
-{
-    QStringList names;
-    QVector<const CompiledData::CompilationUnit*> exportNameSet;
-    getExportedNamesRecursively(&names, &exportNameSet);
-    names.sort();
-    auto last = std::unique(names.begin(), names.end());
-    names.erase(last, names.end());
-    return names;
-}
-
-const Value *CompilationUnit::resolveExportRecursively(QV4::String *exportName, QVector<ResolveSetEntry> *resolveSet)
-{
-    if (!m_module)
-        return nullptr;
-
-    for (const auto &entry: *resolveSet)
-        if (entry.module == this && entry.exportName->isEqualTo(exportName))
-            return nullptr;
-
-    (*resolveSet) << ResolveSetEntry(this, exportName);
-
-    if (exportName->toQString() == QLatin1String("*"))
-        return &m_module->self;
-
-    Scope scope(engine);
-
-    if (auto localExport = lookupNameInExportTable(data->localExportEntryTable(), data->localExportEntryTableSize, exportName)) {
-        ScopedString localName(scope, runtimeStrings[localExport->localName]);
-        uint index = m_module->scope->internalClass->indexOfValueOrGetter(localName->toPropertyKey());
-        if (index == UINT_MAX)
-            return nullptr;
-        if (index >= m_module->scope->locals.size)
-            return imports[index - m_module->scope->locals.size];
-        return &m_module->scope->locals[index];
-    }
-
-    if (auto indirectExport = lookupNameInExportTable(data->indirectExportEntryTable(), data->indirectExportEntryTableSize, exportName)) {
-        auto dependentModuleUnit = engine->loadModule(QUrl(stringAt(indirectExport->moduleRequest)), this);
-        if (!dependentModuleUnit)
-            return nullptr;
-        ScopedString importName(scope, runtimeStrings[indirectExport->importName]);
-        return dependentModuleUnit->resolveExportRecursively(importName, resolveSet);
-    }
-
-
-    if (exportName->toQString() == QLatin1String("default"))
-        return nullptr;
-
-    const Value *starResolution = nullptr;
-
-    for (uint i = 0; i < data->starExportEntryTableSize; ++i) {
-        const CompiledData::ExportEntry &entry = data->starExportEntryTable()[i];
-        auto dependentModuleUnit = engine->loadModule(QUrl(stringAt(entry.moduleRequest)), this);
-        if (!dependentModuleUnit)
-            return nullptr;
-
-        const Value *resolution = dependentModuleUnit->resolveExportRecursively(exportName, resolveSet);
-        // ### handle ambiguous
-        if (resolution) {
-            if (!starResolution) {
-                starResolution = resolution;
-                continue;
-            }
-            if (resolution != starResolution)
-                return nullptr;
-        }
-    }
-
-    return starResolution;
-}
-
-const ExportEntry *CompilationUnit::lookupNameInExportTable(const ExportEntry *firstExportEntry, int tableSize, QV4::String *name) const
-{
-    const CompiledData::ExportEntry *lastExportEntry = firstExportEntry + tableSize;
-    auto matchingExport = std::lower_bound(firstExportEntry, lastExportEntry, name, [this](const CompiledData::ExportEntry &lhs, QV4::String *name) {
-        return stringAt(lhs.exportName) < name->toQString();
-    });
-    if (matchingExport == lastExportEntry || stringAt(matchingExport->exportName) != name->toQString())
-        return nullptr;
-    return matchingExport;
-}
-
-void CompilationUnit::getExportedNamesRecursively(QStringList *names, QVector<const CompilationUnit*> *exportNameSet, bool includeDefaultExport) const
-{
-    if (exportNameSet->contains(this))
-        return;
-    exportNameSet->append(this);
-
-    const auto append = [names, includeDefaultExport](const QString &name) {
-        if (!includeDefaultExport && name == QLatin1String("default"))
-            return;
-        names->append(name);
-    };
-
-    for (uint i = 0; i < data->localExportEntryTableSize; ++i) {
-        const CompiledData::ExportEntry &entry = data->localExportEntryTable()[i];
-        append(stringAt(entry.exportName));
-    }
-
-    for (uint i = 0; i < data->indirectExportEntryTableSize; ++i) {
-        const CompiledData::ExportEntry &entry = data->indirectExportEntryTable()[i];
-        append(stringAt(entry.exportName));
-    }
-
-    for (uint i = 0; i < data->starExportEntryTableSize; ++i) {
-        const CompiledData::ExportEntry &entry = data->starExportEntryTable()[i];
-        auto dependentModuleUnit = engine->loadModule(QUrl(stringAt(entry.moduleRequest)), this);
-        if (!dependentModuleUnit)
-            return;
-        dependentModuleUnit->getExportedNamesRecursively(names, exportNameSet, /*includeDefaultExport*/false);
-    }
-}
-
-void CompilationUnit::evaluate()
-{
-    QV4::Scope scope(engine);
-    QV4::Scoped<Module> module(scope, m_module);
-    module->evaluate();
-}
-
-void CompilationUnit::evaluateModuleRequests()
-{
-    for (const QString &request: moduleRequests()) {
-        auto dependentModuleUnit = engine->loadModule(QUrl(request), this);
-        if (engine->hasException)
-            return;
-        dependentModuleUnit->evaluate();
-        if (engine->hasException)
-            return;
-    }
-}
-
-bool CompilationUnit::loadFromDisk(const QUrl &url, const QDateTime &sourceTimeStamp, QString *errorString)
-{
-    if (!QQmlFile::isLocalFile(url)) {
-        *errorString = QStringLiteral("File has to be a local file.");
-        return false;
-    }
-
-    const QString sourcePath = QQmlFile::urlToLocalFileOrQrc(url);
-    QScopedPointer<CompilationUnitMapper> cacheFile(new CompilationUnitMapper());
-
-    const QStringList cachePaths = { sourcePath + QLatin1Char('c'), localCacheFilePath(url) };
-    for (const QString &cachePath : cachePaths) {
-        CompiledData::Unit *mappedUnit = cacheFile->open(cachePath, sourceTimeStamp, errorString);
-        if (!mappedUnit)
-            continue;
-
-        const Unit * const oldDataPtr = (data && !(data->flags & QV4::CompiledData::Unit::StaticData)) ? data : nullptr;
-        const Unit *oldData = data;
-        auto dataPtrRevert = qScopeGuard([this, oldData](){
-            setUnitData(oldData);
-        });
-        setUnitData(mappedUnit);
-
-        if (data->sourceFileIndex != 0 && sourcePath != QQmlFile::urlToLocalFileOrQrc(stringAt(data->sourceFileIndex))) {
-            *errorString = QStringLiteral("QML source file has moved to a different location.");
-            continue;
-        }
-
-        dataPtrRevert.dismiss();
-        free(const_cast<Unit*>(oldDataPtr));
-        backingFile.reset(cacheFile.take());
-        return true;
-    }
-
-    return false;
-}
-
-#endif // V4_BOOTSTRAP
-
-#if defined(V4_BOOTSTRAP)
-bool CompilationUnit::saveToDisk(const QString &outputFileName, QString *errorString)
-#else
-bool CompilationUnit::saveToDisk(const QUrl &unitUrl, QString *errorString)
-#endif
+bool CompilationUnit::saveToDisk(const QString &outputFileName, QString *errorString) const
 {
     errorString->clear();
 
-#if !defined(V4_BOOTSTRAP)
-    if (data->sourceTimeStamp == 0) {
-        *errorString = QStringLiteral("Missing time stamp for source file");
-        return false;
-    }
-
-    if (!QQmlFile::isLocalFile(unitUrl)) {
-        *errorString = QStringLiteral("File has to be a local file.");
-        return false;
-    }
-    const QString outputFileName = localCacheFilePath(unitUrl);
-#endif
-
 #if QT_CONFIG(temporaryfile)
     // Foo.qml -> Foo.qmlc
     QSaveFile cacheFile(outputFileName);
@@ -713,16 +107,9 @@ bool CompilationUnit::saveToDisk(const QUrl &unitUrl, QString *errorString)
         return false;
     }
 
-    QByteArray modifiedUnit;
-    modifiedUnit.resize(data->unitSize);
-    memcpy(modifiedUnit.data(), data, data->unitSize);
-    const char *dataPtr = modifiedUnit.data();
-    Unit *unitPtr;
-    memcpy(&unitPtr, &dataPtr, sizeof(unitPtr));
-    unitPtr->flags |= Unit::StaticData;
-
-    qint64 headerWritten = cacheFile.write(modifiedUnit);
-    if (headerWritten != modifiedUnit.size()) {
+    SaveableUnitPointer saveable(this);
+    qint64 headerWritten = cacheFile.write(saveable.data<char>(), saveable.size());
+    if (headerWritten != saveable.size()) {
         *errorString = cacheFile.errorString();
         return false;
     }
@@ -770,51 +157,6 @@ void CompilationUnit::setUnitData(const Unit *unitData, const QmlUnit *qmlUnit,
     m_finalUrlString = !finalUrlString.isEmpty() ? finalUrlString : stringAt(data->finalUrlIndex);
 }
 
-#ifndef V4_BOOTSTRAP
-QString Binding::valueAsString(const CompilationUnit *unit) const
-{
-    switch (type) {
-    case Type_Script:
-    case Type_String:
-        return unit->stringAt(stringIndex);
-    case Type_Null:
-        return QStringLiteral("null");
-    case Type_Boolean:
-        return value.b ? QStringLiteral("true") : QStringLiteral("false");
-    case Type_Number:
-        return QString::number(valueAsNumber(unit->constants));
-    case Type_Invalid:
-        return QString();
-#if !QT_CONFIG(translation)
-    case Type_TranslationById:
-    case Type_Translation:
-        return unit->stringAt(unit->unitData()->translations()[value.translationDataIndex].stringIndex);
-#else
-    case Type_TranslationById: {
-        const TranslationData &translation = unit->unitData()->translations()[value.translationDataIndex];
-        QByteArray id = unit->stringAt(translation.stringIndex).toUtf8();
-        return qtTrId(id.constData(), translation.number);
-    }
-    case Type_Translation: {
-        const TranslationData &translation = unit->unitData()->translations()[value.translationDataIndex];
-        // This code must match that in the qsTr() implementation
-        const QString &path = unit->fileName();
-        int lastSlash = path.lastIndexOf(QLatin1Char('/'));
-        QStringRef context = (lastSlash > -1) ? path.midRef(lastSlash + 1, path.length() - lastSlash - 5)
-                                              : QStringRef();
-        QByteArray contextUtf8 = context.toUtf8();
-        QByteArray comment = unit->stringAt(translation.commentIndex).toUtf8();
-        QByteArray text = unit->stringAt(translation.stringIndex).toUtf8();
-        return QCoreApplication::translate(contextUtf8.constData(), text.constData(),
-                                           comment.constData(), translation.number);
-    }
-#endif
-    default:
-        break;
-    }
-    return QString();
-}
-
 //reverse of Lexer::singleEscape()
 QString Binding::escapedString(const QString &string)
 {
@@ -858,101 +200,19 @@ QString Binding::escapedString(const QString &string)
     return tmp;
 }
 
-QString Binding::valueAsScriptString(const CompilationUnit *unit) const
-{
-    if (type == Type_String)
-        return escapedString(unit->stringAt(stringIndex));
-    else
-        return valueAsString(unit);
-}
-
-/*!
-Returns the property cache, if one alread exists.  The cache is not referenced.
-*/
-QQmlRefPointer<QQmlPropertyCache> ResolvedTypeReference::propertyCache() const
-{
-    if (type.isValid())
-        return typePropertyCache;
-    else
-        return compilationUnit->rootPropertyCache();
-}
-
-/*!
-Returns the property cache, creating one if it doesn't already exist.  The cache is not referenced.
-*/
-QQmlRefPointer<QQmlPropertyCache> ResolvedTypeReference::createPropertyCache(QQmlEngine *engine)
-{
-    if (typePropertyCache) {
-        return typePropertyCache;
-    } else if (type.isValid()) {
-        typePropertyCache = QQmlEnginePrivate::get(engine)->cache(type.metaObject(), minorVersion);
-        return typePropertyCache;
-    } else {
-        return compilationUnit->rootPropertyCache();
-    }
-}
-
-bool ResolvedTypeReference::addToHash(QCryptographicHash *hash, QQmlEngine *engine)
-{
-    if (type.isValid()) {
-        bool ok = false;
-        hash->addData(createPropertyCache(engine)->checksum(&ok));
-        return ok;
-    }
-    if (!compilationUnit)
-        return false;
-    hash->addData(compilationUnit->unitData()->md5Checksum, sizeof(compilationUnit->unitData()->md5Checksum));
-    return true;
-}
-
-template <typename T>
-bool qtTypeInherits(const QMetaObject *mo) {
-    while (mo) {
-        if (mo == &T::staticMetaObject)
-            return true;
-        mo = mo->superClass();
-    }
-    return false;
-}
-
-void ResolvedTypeReference::doDynamicTypeCheck()
-{
-    const QMetaObject *mo = nullptr;
-    if (typePropertyCache)
-        mo = typePropertyCache->firstCppMetaObject();
-    else if (type.isValid())
-        mo = type.metaObject();
-    else if (compilationUnit)
-        mo = compilationUnit->rootPropertyCache()->firstCppMetaObject();
-    isFullyDynamicType = qtTypeInherits<QQmlPropertyMap>(mo);
-}
-
-bool ResolvedTypeReferenceMap::addToHash(QCryptographicHash *hash, QQmlEngine *engine) const
-{
-    for (auto it = constBegin(), end = constEnd(); it != end; ++it) {
-        if (!it.value()->addToHash(hash, engine))
-            return false;
-    }
-
-    return true;
-}
-
-#endif
-
-void CompilationUnit::destroy()
+void CompilationUnit::unlink()
 {
-#if !defined(V4_BOOTSTRAP)
-    if (qmlEngine)
-        QQmlEnginePrivate::deleteInEngineThread(qmlEngine, this);
-    else
-#endif
-        delete this;
+    free(runtimeStrings);
+    runtimeStrings = nullptr;
+    delete [] runtimeRegularExpressions;
+    runtimeRegularExpressions = nullptr;
+    free(runtimeClasses);
+    runtimeClasses = nullptr;
 }
 
-
 void Unit::generateChecksum()
 {
-#ifndef V4_BOOTSTRAP
+#ifndef QT_CRYPTOGRAPHICHASH_ONLY_SHA1
     QCryptographicHash hash(QCryptographicHash::Md5);
 
     const int checksummableDataOffset = offsetof(QV4::CompiledData::Unit, md5Checksum) + sizeof(md5Checksum);
@@ -970,7 +230,6 @@ void Unit::generateChecksum()
 
 bool Unit::verifyHeader(QDateTime expectedSourceTimeStamp, QString *errorString) const
 {
-#ifndef V4_BOOTSTRAP
     if (strncmp(magic, CompiledData::magic_str, sizeof(magic))) {
         *errorString = QStringLiteral("Magic bytes in the header do not match");
         return false;
@@ -1008,11 +267,6 @@ bool Unit::verifyHeader(QDateTime expectedSourceTimeStamp, QString *errorString)
 #endif
 
     return true;
-#else
-    Q_UNUSED(expectedSourceTimeStamp)
-    Q_UNUSED(errorString)
-    return false;
-#endif
 }
 
 Location &Location::operator=(const QQmlJS::AST::SourceLocation &astLocation)
diff --git a/src/qml/compiler/qv4compileddata_p.h b/src/qml/compiler/qv4compileddata_p.h
index dd7ba471c3..94b64694ae 100644
--- a/src/qml/compiler/qv4compileddata_p.h
+++ b/src/qml/compiler/qv4compileddata_p.h
@@ -51,12 +51,12 @@
 //
 
 #include <QtCore/qstring.h>
+#include <QtCore/qcryptographichash.h>
 #include <QVector>
 #include <QStringList>
 #include <QHash>
 #include <QUrl>
 
-#include <private/qv4value_p.h>
 #include <private/qv4executableallocator_p.h>
 #include <private/qqmlrefcount_p.h>
 #include <private/qqmlnullablevalue_p.h>
@@ -64,11 +64,6 @@
 #include <private/qflagpointer_p.h>
 #include <private/qendian_p.h>
 #include <private/qqmljsastfwd_p.h>
-#ifndef V4_BOOTSTRAP
-#include <private/qqmltypenamecache_p.h>
-#include <private/qqmlpropertycachevector_p.h>
-#include "private/qintrusivelist_p.h"
-#endif
 
 QT_BEGIN_NAMESPACE
 
@@ -100,7 +95,6 @@ struct Module;
 
 struct Function;
 class EvalISelFactory;
-class CompilationUnitMapper;
 
 namespace CompiledData {
 
@@ -527,17 +521,6 @@ struct Q_QML_PRIVATE_EXPORT Binding
     bool isTranslationBinding() const { return type == Type_Translation || type == Type_TranslationById; }
     bool evaluatesToString() const { return type == Type_String || isTranslationBinding(); }
 
-#ifndef V4_BOOTSTRAP
-    QString valueAsString(const CompilationUnit *unit) const;
-    QString valueAsScriptString(const CompilationUnit *unit) const;
-#endif
-    double valueAsNumber(const Value *constantTable) const
-    {
-        if (type != Type_Number)
-            return 0.0;
-        return constantTable[value.constantValueIndex].doubleValue();
-    }
-
     bool valueAsBoolean() const
     {
         if (type == Type_Boolean)
@@ -903,6 +886,10 @@ struct Unit
         return reinterpret_cast<const QmlUnit *>(reinterpret_cast<const char *>(this) + offsetToQmlUnit);
     }
 
+    QmlUnit *qmlUnit() {
+        return reinterpret_cast<QmlUnit *>(reinterpret_cast<char *>(this) + offsetToQmlUnit);
+    }
+
     bool isSingleton() const {
         return flags & Unit::IsSingleton;
     }
@@ -1048,20 +1035,7 @@ struct TypeReferenceMap : QHash<int, TypeReference>
     }
 };
 
-#ifndef V4_BOOTSTRAP
-struct ResolvedTypeReference;
-// map from name index
-// While this could be a hash, a map is chosen here to provide a stable
-// order, which is used to calculating a check-sum on dependent meta-objects.
-struct ResolvedTypeReferenceMap: public QMap<int, ResolvedTypeReference*>
-{
-    bool addToHash(QCryptographicHash *hash, QQmlEngine *engine) const;
-};
-
-using DependentTypesHasher = std::function<bool(QCryptographicHash *)>;
-#else
-struct DependentTypesHasher {};
-#endif
+using DependentTypesHasher = std::function<QByteArray()>;
 
 // index is per-object binding index
 typedef QVector<QQmlPropertyData*> BindingPropertyData;
@@ -1070,6 +1044,30 @@ typedef QVector<QQmlPropertyData*> BindingPropertyData;
 
 struct Q_QML_PRIVATE_EXPORT CompilationUnitBase
 {
+    Q_DISABLE_COPY(CompilationUnitBase)
+
+    CompilationUnitBase() = default;
+    ~CompilationUnitBase() = default;
+
+    CompilationUnitBase(CompilationUnitBase &&other) noexcept { *this = std::move(other); }
+
+    CompilationUnitBase &operator=(CompilationUnitBase &&other) noexcept
+    {
+        if (this != &other) {
+            runtimeStrings = other.runtimeStrings;
+            other.runtimeStrings = nullptr;
+            constants = other.constants;
+            other.constants = nullptr;
+            runtimeRegularExpressions = other.runtimeRegularExpressions;
+            other.runtimeRegularExpressions = nullptr;
+            runtimeClasses = other.runtimeClasses;
+            other.runtimeClasses = nullptr;
+            imports = other.imports;
+            other.imports = nullptr;
+        }
+        return *this;
+    }
+
     // pointers either to data->constants() or little-endian memory copy.
     QV4::Heap::String **runtimeStrings = nullptr; // Array
     const Value* constants = nullptr;
@@ -1085,105 +1083,48 @@ Q_STATIC_ASSERT(offsetof(CompilationUnitBase, runtimeRegularExpressions) == offs
 Q_STATIC_ASSERT(offsetof(CompilationUnitBase, runtimeClasses) == offsetof(CompilationUnitBase, runtimeRegularExpressions) + sizeof(const Value *));
 Q_STATIC_ASSERT(offsetof(CompilationUnitBase, imports) == offsetof(CompilationUnitBase, runtimeClasses) + sizeof(const Value *));
 
-struct Q_QML_PRIVATE_EXPORT CompilationUnit final : public CompilationUnitBase
+struct Q_QML_PRIVATE_EXPORT CompilationUnit : public CompilationUnitBase
 {
+    Q_DISABLE_COPY(CompilationUnit)
+
     const Unit *data = nullptr;
     const QmlUnit *qmlData = nullptr;
+    QStringList dynamicStrings;
 public:
+    using CompiledObject = CompiledData::Object;
+
     CompilationUnit(const Unit *unitData = nullptr, const QString &fileName = QString(), const QString &finalUrlString = QString());
     ~CompilationUnit();
 
-    void addref()
+    CompilationUnit(CompilationUnit &&other) noexcept
     {
-        Q_ASSERT(refCount.load() > 0);
-        refCount.ref();
+        *this = std::move(other);
     }
 
-    void release()
+    CompilationUnit &operator=(CompilationUnit &&other) noexcept
     {
-        Q_ASSERT(refCount.load() > 0);
-        if (!refCount.deref())
-            destroy();
-    }
-    int count() const
-    {
-        return refCount.load();
+        if (this != &other) {
+            data = other.data;
+            other.data = nullptr;
+            qmlData = other.qmlData;
+            other.qmlData = nullptr;
+            dynamicStrings = std::move(other.dynamicStrings);
+            other.dynamicStrings.clear();
+            m_fileName = std::move(other.m_fileName);
+            other.m_fileName.clear();
+            m_finalUrlString = std::move(other.m_finalUrlString);
+            other.m_finalUrlString.clear();
+            m_module = other.m_module;
+            other.m_module = nullptr;
+            CompilationUnitBase::operator=(std::move(other));
+        }
+        return *this;
     }
 
     const Unit *unitData() const { return data; }
     void setUnitData(const Unit *unitData, const QmlUnit *qmlUnit = nullptr,
                      const QString &fileName = QString(), const QString &finalUrlString = QString());
 
-#ifndef V4_BOOTSTRAP
-    QIntrusiveListNode nextCompilationUnit;
-    ExecutionEngine *engine = nullptr;
-    QQmlEnginePrivate *qmlEngine = nullptr; // only used in QML environment for composite types, not in plain QJSEngine case.
-
-    // url() and fileName() shall be used to load the actual QML/JS code or to show errors or
-    // warnings about that code. They include any potential URL interceptions and thus represent the
-    // "physical" location of the code.
-    //
-    // finalUrl() and finalUrlString() shall be used to resolve further URLs referred to in the code
-    // They are _not_ intercepted and thus represent the "logical" name for the code.
-
-    QString fileName() const { return m_fileName; }
-    QString finalUrlString() const { return m_finalUrlString; }
-    QUrl url() const { if (m_url.isNull) m_url = QUrl(fileName()); return m_url; }
-    QUrl finalUrl() const
-    {
-        if (m_finalUrl.isNull)
-            m_finalUrl = QUrl(finalUrlString());
-        return m_finalUrl;
-    }
-
-    QV4::Lookup *runtimeLookups = nullptr;
-    QVector<QV4::Function *> runtimeFunctions;
-    QVector<QV4::Heap::InternalClass *> runtimeBlocks;
-    mutable QVector<QV4::Heap::Object *> templateObjects;
-    mutable QQmlNullableValue<QUrl> m_url;
-    mutable QQmlNullableValue<QUrl> m_finalUrl;
-
-    // QML specific fields
-    QQmlPropertyCacheVector propertyCaches;
-    QQmlRefPointer<QQmlPropertyCache> rootPropertyCache() const { return propertyCaches.at(/*root object*/0); }
-
-    QQmlRefPointer<QQmlTypeNameCache> typeNameCache;
-
-    // index is object index. This allows fast access to the
-    // property data when initializing bindings, avoiding expensive
-    // lookups by string (property name).
-    QVector<BindingPropertyData> bindingPropertyDataPerObject;
-
-    // mapping from component object index (CompiledData::Unit object index that points to component) to identifier hash of named objects
-    // this is initialized on-demand by QQmlContextData
-    QHash<int, IdentifierHash> namedObjectsPerComponentCache;
-    inline IdentifierHash namedObjectsPerComponent(int componentObjectIndex);
-
-    void finalizeCompositeType(QQmlEnginePrivate *qmlEngine);
-
-    int totalBindingsCount = 0; // Number of bindings used in this type
-    int totalParserStatusCount = 0; // Number of instantiated types that are QQmlParserStatus subclasses
-    int totalObjectCount = 0; // Number of objects explicitly instantiated
-
-    QVector<QQmlRefPointer<QQmlScriptData>> dependentScripts;
-    ResolvedTypeReferenceMap resolvedTypes;
-    ResolvedTypeReference *resolvedType(int id) const { return resolvedTypes.value(id); }
-
-    bool verifyChecksum(const DependentTypesHasher &dependencyHasher) const;
-
-    int metaTypeId = -1;
-    int listMetaTypeId = -1;
-    bool isRegisteredWithEngine = false;
-
-    QScopedPointer<CompilationUnitMapper> backingFile;
-    QStringList dynamicStrings;
-
-    // --- interface for QQmlPropertyCacheCreator
-    typedef Object CompiledObject;
-    int objectCount() const { return qmlData->nObjects; }
-    const Object *objectAt(int index) const { return qmlData->objectAt(index); }
-    int importCount() const { return qmlData->nImports; }
-    const Import *importAt(int index) const { return qmlData->importAt(index); }
     QString stringAt(int index) const
     {
         if (uint(index) >= data->stringTableSize)
@@ -1191,117 +1132,66 @@ public:
         return data->stringAtInternal(index);
     }
 
-    Heap::Object *templateObjectAt(int index) const;
-
-    struct FunctionIterator
-    {
-        FunctionIterator(const Unit *unit, const Object *object, int index) : unit(unit), object(object), index(index) {}
-        const Unit *unit;
-        const Object *object;
-        int index;
-
-        const Function *operator->() const { return unit->functionAt(object->functionOffsetTable()[index]); }
-        void operator++() { ++index; }
-        bool operator==(const FunctionIterator &rhs) const { return index == rhs.index; }
-        bool operator!=(const FunctionIterator &rhs) const { return index != rhs.index; }
-    };
-    FunctionIterator objectFunctionsBegin(const Object *object) const { return FunctionIterator(data, object, 0); }
-    FunctionIterator objectFunctionsEnd(const Object *object) const { return FunctionIterator(data, object, object->nFunctions); }
-    // ---
+    QString fileName() const { return m_fileName; }
+    QString finalUrlString() const { return m_finalUrlString; }
 
-    bool isESModule() const { return data->flags & Unit::IsESModule; }
-    bool isSharedLibrary() const { return data->flags & Unit::IsSharedLibrary; }
-    QStringList moduleRequests() const;
-    Heap::Module *instantiate(ExecutionEngine *engine);
-    const Value *resolveExport(QV4::String *exportName);
-    QStringList exportedNames() const;
-    void evaluate();
-    void evaluateModuleRequests();
+    Heap::Module *module() const { return m_module; }
+    void setModule(Heap::Module *module) { m_module = module; }
 
-    QV4::Function *linkToEngine(QV4::ExecutionEngine *engine);
     void unlink();
 
-    void markObjects(MarkStack *markStack);
-
-    bool loadFromDisk(const QUrl &url, const QDateTime &sourceTimeStamp, QString *errorString);
-
-    static QString localCacheFilePath(const QUrl &url);
-
-protected:
-    quint32 totalStringCount() const
-    { return data->stringTableSize; }
-
-#else // V4_BOOTSTRAP
-    QString stringAt(int index) const { return data->stringAtInternal(index); }
-#endif // V4_BOOTSTRAP
-
 private:
-    void destroy();
-
-    struct ResolveSetEntry
-    {
-        ResolveSetEntry() {}
-        ResolveSetEntry(CompilationUnit *module, QV4::String *exportName)
-            : module(module), exportName(exportName) {}
-        CompilationUnit *module = nullptr;
-        QV4::String *exportName = nullptr;
-    };
-
-    const Value *resolveExportRecursively(QV4::String *exportName, QVector<ResolveSetEntry> *resolveSet);
-    const ExportEntry *lookupNameInExportTable(const ExportEntry *firstExportEntry, int tableSize, QV4::String *name) const;
-    void getExportedNamesRecursively(QStringList *names, QVector<const CompilationUnit *> *exportNameSet, bool includeDefaultExport = true) const;
-
     QString m_fileName; // initialized from data->sourceFileIndex
     QString m_finalUrlString; // initialized from data->finalUrlIndex
 
-    QAtomicInt refCount = 1;
-
-    Q_NEVER_INLINE IdentifierHash createNamedObjectsPerComponent(int componentObjectIndex);
-
     Heap::Module *m_module = nullptr;
 
 public:
-#if defined(V4_BOOTSTRAP)
-    bool saveToDisk(const QString &outputFileName, QString *errorString);
-#else
-    bool saveToDisk(const QUrl &unitUrl, QString *errorString);
-#endif
+    bool saveToDisk(const QString &outputFileName, QString *errorString) const;
 };
 
-#ifndef V4_BOOTSTRAP
-struct ResolvedTypeReference
+class SaveableUnitPointer
 {
-    ResolvedTypeReference()
-        : majorVersion(0)
-        , minorVersion(0)
-        , isFullyDynamicType(false)
-    {}
+    Q_DISABLE_COPY_MOVE(SaveableUnitPointer)
+public:
+    SaveableUnitPointer(const CompilationUnit *unit, quint32 temporaryFlags = Unit::StaticData) :
+          unit(unit)
+    {
+        quint32_le &unitFlags = mutableFlags();
+        quint32 origFlags = unitFlags;
+        unitFlags |= temporaryFlags;
+        changedFlags = origFlags ^ unitFlags;
+    }
 
-    QQmlType type;
-    QQmlRefPointer<QQmlPropertyCache> typePropertyCache;
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> compilationUnit;
+    ~SaveableUnitPointer()
+    {
+        mutableFlags() ^= changedFlags;
+    }
 
-    int majorVersion;
-    int minorVersion;
-    // Types such as QQmlPropertyMap can add properties dynamically at run-time and
-    // therefore cannot have a property cache installed when instantiated.
-    bool isFullyDynamicType;
+    const CompilationUnit *operator->() const { return unit; }
+    const CompilationUnit &operator*() const { return *unit; }
+    operator const CompilationUnit *() { return unit; }
 
-    QQmlRefPointer<QQmlPropertyCache> propertyCache() const;
-    QQmlRefPointer<QQmlPropertyCache> createPropertyCache(QQmlEngine *);
-    bool addToHash(QCryptographicHash *hash, QQmlEngine *engine);
+    template<typename Char>
+    const Char *data() const
+    {
+        Q_STATIC_ASSERT(sizeof(Char) == 1);
+        const Char *dataPtr;
+        memcpy(&dataPtr, &unit->data, sizeof(dataPtr));
+        return dataPtr;
+    }
 
-    void doDynamicTypeCheck();
+    quint32 size() const
+    {
+        return unit->data->unitSize;
+    }
+
+private:
+    quint32_le &mutableFlags() { return const_cast<Unit *>(unit->unitData())->flags; };
+    const CompilationUnit *unit;
+    quint32 changedFlags;
 };
 
-IdentifierHash CompilationUnit::namedObjectsPerComponent(int componentObjectIndex)
-{
-    auto it = namedObjectsPerComponentCache.find(componentObjectIndex);
-    if (Q_UNLIKELY(it == namedObjectsPerComponentCache.end()))
-        return createNamedObjectsPerComponent(componentObjectIndex);
-    return *it;
-}
-#endif // V4_BOOTSTRAP
 
 } // CompiledData namespace
 } // QV4 namespace
diff --git a/src/qml/compiler/qv4compiler.cpp b/src/qml/compiler/qv4compiler.cpp
index 123d77f788..4a54e5a44b 100644
--- a/src/qml/compiler/qv4compiler.cpp
+++ b/src/qml/compiler/qv4compiler.cpp
@@ -40,7 +40,6 @@
 #include <qv4compiler_p.h>
 #include <qv4compileddata_p.h>
 #include <qv4codegen_p.h>
-#include <private/qv4string_p.h>
 #include <private/qv4value_p.h>
 #include <private/qv4alloca_p.h>
 #include <private/qqmljslexer_p.h>
diff --git a/src/qml/compiler/qv4compilerscanfunctions.cpp b/src/qml/compiler/qv4compilerscanfunctions.cpp
index 8984b6931e..ef67a11a70 100644
--- a/src/qml/compiler/qv4compilerscanfunctions.cpp
+++ b/src/qml/compiler/qv4compilerscanfunctions.cpp
@@ -49,7 +49,6 @@
 #include <private/qqmljsast_p.h>
 #include <private/qv4compilercontext_p.h>
 #include <private/qv4codegen_p.h>
-#include <private/qv4string_p.h>
 
 QT_USE_NAMESPACE
 using namespace QV4;
diff --git a/src/qml/compiler/qv4executablecompilationunit.cpp b/src/qml/compiler/qv4executablecompilationunit.cpp
new file mode 100644
index 0000000000..97c828d4d8
--- /dev/null
+++ b/src/qml/compiler/qv4executablecompilationunit.cpp
@@ -0,0 +1,809 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the tools applications of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qv4executablecompilationunit_p.h"
+
+#include <private/qv4engine_p.h>
+#include <private/qv4regexp_p.h>
+#include <private/qv4lookup_p.h>
+#include <private/qv4qmlcontext_p.h>
+#include <private/qv4identifiertable_p.h>
+#include <private/qv4instr_moth_p.h>
+#include <private/qv4objectproto_p.h>
+#include <private/qqmlengine_p.h>
+#include <private/qv4qobjectwrapper_p.h>
+#include <private/qqmlvaluetypewrapper_p.h>
+#include <private/qv4module_p.h>
+#include <private/qv4compilationunitmapper_p.h>
+
+#include <QtQml/qqmlfile.h>
+#include <QtQml/qqmlpropertymap.h>
+
+#include <QtCore/qdir.h>
+#include <QtCore/qstandardpaths.h>
+#include <QtCore/qfileinfo.h>
+#include <QtCore/qscopeguard.h>
+
+QT_BEGIN_NAMESPACE
+
+namespace QV4 {
+
+ExecutableCompilationUnit::ExecutableCompilationUnit() = default;
+
+ExecutableCompilationUnit::ExecutableCompilationUnit(
+        CompiledData::CompilationUnit &&compilationUnit)
+    : CompiledData::CompilationUnit(std::move(compilationUnit))
+{}
+
+ExecutableCompilationUnit::~ExecutableCompilationUnit()
+{
+    unlink();
+}
+
+QString ExecutableCompilationUnit::localCacheFilePath(const QUrl &url)
+{
+    const QString localSourcePath = QQmlFile::urlToLocalFileOrQrc(url);
+    const QString cacheFileSuffix = QFileInfo(localSourcePath + QLatin1Char('c')).completeSuffix();
+    QCryptographicHash fileNameHash(QCryptographicHash::Sha1);
+    fileNameHash.addData(localSourcePath.toUtf8());
+    QString directory = QStandardPaths::writableLocation(QStandardPaths::CacheLocation) + QLatin1String("/qmlcache/");
+    QDir::root().mkpath(directory);
+    return directory + QString::fromUtf8(fileNameHash.result().toHex()) + QLatin1Char('.') + cacheFileSuffix;
+}
+
+static QString toString(QV4::ReturnedValue v)
+{
+    Value val = Value::fromReturnedValue(v);
+    QString result;
+    if (val.isInt32())
+        result = QLatin1String("int ");
+    else if (val.isDouble())
+        result = QLatin1String("double ");
+    if (val.isEmpty())
+        result += QLatin1String("empty");
+    else
+        result += val.toQStringNoThrow();
+    return result;
+}
+
+static void dumpConstantTable(const Value *constants, uint count)
+{
+    QDebug d = qDebug();
+    d.nospace() << right;
+    for (uint i = 0; i < count; ++i) {
+        d << qSetFieldWidth(8) << i << qSetFieldWidth(0) << ":    "
+          << toString(constants[i].asReturnedValue()).toUtf8().constData() << "\n";
+    }
+}
+
+QV4::Function *ExecutableCompilationUnit::linkToEngine(ExecutionEngine *engine)
+{
+    this->engine = engine;
+    engine->compilationUnits.insert(this);
+
+    Q_ASSERT(!runtimeStrings);
+    Q_ASSERT(data);
+    const quint32 stringCount = totalStringCount();
+    runtimeStrings = (QV4::Heap::String **)malloc(stringCount * sizeof(QV4::Heap::String*));
+    // memset the strings to 0 in case a GC run happens while we're within the loop below
+    memset(runtimeStrings, 0, stringCount * sizeof(QV4::Heap::String*));
+    for (uint i = 0; i < stringCount; ++i)
+        runtimeStrings[i] = engine->newString(stringAt(i));
+
+    runtimeRegularExpressions
+            = new QV4::Value[data->regexpTableSize];
+    // memset the regexps to 0 in case a GC run happens while we're within the loop below
+    memset(runtimeRegularExpressions, 0,
+           data->regexpTableSize * sizeof(QV4::Value));
+    for (uint i = 0; i < data->regexpTableSize; ++i) {
+        const CompiledData::RegExp *re = data->regexpAt(i);
+        uint f = re->flags;
+        const CompiledData::RegExp::Flags flags = static_cast<CompiledData::RegExp::Flags>(f);
+        runtimeRegularExpressions[i] = QV4::RegExp::create(
+                engine, stringAt(re->stringIndex), flags);
+    }
+
+    if (data->lookupTableSize) {
+        runtimeLookups = new QV4::Lookup[data->lookupTableSize];
+        memset(runtimeLookups, 0, data->lookupTableSize * sizeof(QV4::Lookup));
+        const CompiledData::Lookup *compiledLookups = data->lookupTable();
+        for (uint i = 0; i < data->lookupTableSize; ++i) {
+            QV4::Lookup *l = runtimeLookups + i;
+
+            CompiledData::Lookup::Type type
+                    = CompiledData::Lookup::Type(uint(compiledLookups[i].type_and_flags));
+            if (type == CompiledData::Lookup::Type_Getter)
+                l->getter = QV4::Lookup::getterGeneric;
+            else if (type == CompiledData::Lookup::Type_Setter)
+                l->setter = QV4::Lookup::setterGeneric;
+            else if (type == CompiledData::Lookup::Type_GlobalGetter)
+                l->globalGetter = QV4::Lookup::globalGetterGeneric;
+            else if (type == CompiledData::Lookup::Type_QmlContextPropertyGetter)
+                l->qmlContextPropertyGetter = QQmlContextWrapper::resolveQmlContextPropertyLookupGetter;
+            l->nameIndex = compiledLookups[i].nameIndex;
+        }
+    }
+
+    if (data->jsClassTableSize) {
+        runtimeClasses
+                = (QV4::Heap::InternalClass **)malloc(data->jsClassTableSize
+                                                      * sizeof(QV4::Heap::InternalClass *));
+        // memset the regexps to 0 in case a GC run happens while we're within the loop below
+        memset(runtimeClasses, 0,
+               data->jsClassTableSize * sizeof(QV4::Heap::InternalClass *));
+        for (uint i = 0; i < data->jsClassTableSize; ++i) {
+            int memberCount = 0;
+            const CompiledData::JSClassMember *member
+                    = data->jsClassAt(i, &memberCount);
+            runtimeClasses[i]
+                    = engine->internalClasses(QV4::ExecutionEngine::Class_Object);
+            for (int j = 0; j < memberCount; ++j, ++member)
+                runtimeClasses[i]
+                        = runtimeClasses[i]->addMember(
+                                engine->identifierTable->asPropertyKey(
+                                        runtimeStrings[member->nameOffset]),
+                                member->isAccessor
+                                        ? QV4::Attr_Accessor
+                                        : QV4::Attr_Data);
+        }
+    }
+
+    runtimeFunctions.resize(data->functionTableSize);
+    for (int i = 0 ;i < runtimeFunctions.size(); ++i) {
+        const QV4::CompiledData::Function *compiledFunction = data->functionAt(i);
+        runtimeFunctions[i] = QV4::Function::create(engine, this, compiledFunction);
+    }
+
+    Scope scope(engine);
+    Scoped<InternalClass> ic(scope);
+
+    runtimeBlocks.resize(data->blockTableSize);
+    for (int i = 0 ;i < runtimeBlocks.size(); ++i) {
+        const QV4::CompiledData::Block *compiledBlock = data->blockAt(i);
+        ic = engine->internalClasses(EngineBase::Class_CallContext);
+
+        // first locals
+        const quint32_le *localsIndices = compiledBlock->localsTable();
+        for (quint32 j = 0; j < compiledBlock->nLocals; ++j)
+            ic = ic->addMember(
+                    engine->identifierTable->asPropertyKey(runtimeStrings[localsIndices[j]]),
+                    Attr_NotConfigurable);
+        runtimeBlocks[i] = ic->d();
+    }
+
+    static const bool showCode = qEnvironmentVariableIsSet("QV4_SHOW_BYTECODE");
+    if (showCode) {
+        qDebug() << "=== Constant table";
+        dumpConstantTable(constants, data->constantTableSize);
+        qDebug() << "=== String table";
+        for (uint i = 0, end = totalStringCount(); i < end; ++i)
+            qDebug() << "    " << i << ":" << runtimeStrings[i]->toQString();
+        qDebug() << "=== Closure table";
+        for (uint i = 0; i < data->functionTableSize; ++i)
+            qDebug() << "    " << i << ":" << runtimeFunctions[i]->name()->toQString();
+        qDebug() << "root function at index "
+                 << (data->indexOfRootFunction != -1
+                             ? data->indexOfRootFunction : 0);
+    }
+
+    if (data->indexOfRootFunction != -1)
+        return runtimeFunctions[data->indexOfRootFunction];
+    else
+        return nullptr;
+}
+
+Heap::Object *ExecutableCompilationUnit::templateObjectAt(int index) const
+{
+    Q_ASSERT(index < int(data->templateObjectTableSize));
+    if (!templateObjects.size())
+        templateObjects.resize(data->templateObjectTableSize);
+    Heap::Object *o = templateObjects.at(index);
+    if (o)
+        return o;
+
+    // create the template object
+    Scope scope(engine);
+    const CompiledData::TemplateObject *t = data->templateObjectAt(index);
+    Scoped<ArrayObject> a(scope, engine->newArrayObject(t->size));
+    Scoped<ArrayObject> raw(scope, engine->newArrayObject(t->size));
+    ScopedValue s(scope);
+    for (uint i = 0; i < t->size; ++i) {
+        s = runtimeStrings[t->stringIndexAt(i)];
+        a->arraySet(i, s);
+        s = runtimeStrings[t->rawStringIndexAt(i)];
+        raw->arraySet(i, s);
+    }
+
+    ObjectPrototype::method_freeze(engine->functionCtor(), nullptr, raw, 1);
+    a->defineReadonlyProperty(QStringLiteral("raw"), raw);
+    ObjectPrototype::method_freeze(engine->functionCtor(), nullptr, a, 1);
+
+    templateObjects[index] = a->objectValue()->d();
+    return templateObjects.at(index);
+}
+
+void ExecutableCompilationUnit::unlink()
+{
+    if (engine)
+        nextCompilationUnit.remove();
+
+    if (isRegisteredWithEngine) {
+        Q_ASSERT(data && propertyCaches.count() > 0 && propertyCaches.at(/*root object*/0));
+        if (qmlEngine)
+            qmlEngine->unregisterInternalCompositeType(this);
+        QQmlMetaType::unregisterInternalCompositeType(this);
+        isRegisteredWithEngine = false;
+    }
+
+    propertyCaches.clear();
+
+    if (runtimeLookups) {
+        for (uint i = 0; i < data->lookupTableSize; ++i) {
+            QV4::Lookup &l = runtimeLookups[i];
+            if (l.getter == QV4::QObjectWrapper::lookupGetter) {
+                if (QQmlPropertyCache *pc = l.qobjectLookup.propertyCache)
+                    pc->release();
+            } else if (l.getter == QQmlValueTypeWrapper::lookupGetter) {
+                if (QQmlPropertyCache *pc = l.qgadgetLookup.propertyCache)
+                    pc->release();
+            }
+
+            if (l.qmlContextPropertyGetter == QQmlContextWrapper::lookupScopeObjectProperty) {
+                if (QQmlPropertyCache *pc = l.qobjectLookup.propertyCache)
+                    pc->release();
+            }
+        }
+    }
+
+    dependentScripts.clear();
+
+    typeNameCache = nullptr;
+
+    qDeleteAll(resolvedTypes);
+    resolvedTypes.clear();
+
+    engine = nullptr;
+    qmlEngine = nullptr;
+
+    delete [] runtimeLookups;
+    runtimeLookups = nullptr;
+
+    for (QV4::Function *f : qAsConst(runtimeFunctions))
+        f->destroy();
+    runtimeFunctions.clear();
+
+    CompiledData::CompilationUnit::unlink();
+}
+
+void ExecutableCompilationUnit::markObjects(QV4::MarkStack *markStack)
+{
+    if (runtimeStrings) {
+        for (uint i = 0, end = totalStringCount(); i < end; ++i)
+            if (runtimeStrings[i])
+                runtimeStrings[i]->mark(markStack);
+    }
+    if (runtimeRegularExpressions) {
+        for (uint i = 0; i < data->regexpTableSize; ++i)
+            runtimeRegularExpressions[i].mark(markStack);
+    }
+    if (runtimeClasses) {
+        for (uint i = 0; i < data->jsClassTableSize; ++i)
+            if (runtimeClasses[i])
+                runtimeClasses[i]->mark(markStack);
+    }
+    for (QV4::Function *f : qAsConst(runtimeFunctions))
+        if (f && f->internalClass)
+            f->internalClass->mark(markStack);
+    for (QV4::Heap::InternalClass *c : qAsConst(runtimeBlocks))
+        if (c)
+            c->mark(markStack);
+
+    for (QV4::Heap::Object *o : qAsConst(templateObjects))
+        if (o)
+            o->mark(markStack);
+
+    if (runtimeLookups) {
+        for (uint i = 0; i < data->lookupTableSize; ++i)
+            runtimeLookups[i].markObjects(markStack);
+    }
+
+    if (auto mod = module())
+        mod->mark(markStack);
+}
+
+IdentifierHash ExecutableCompilationUnit::createNamedObjectsPerComponent(int componentObjectIndex)
+{
+    IdentifierHash namedObjectCache(engine);
+    const CompiledData::Object *component = objectAt(componentObjectIndex);
+    const quint32_le *namedObjectIndexPtr = component->namedObjectsInComponentTable();
+    for (quint32 i = 0; i < component->nNamedObjectsInComponent; ++i, ++namedObjectIndexPtr) {
+        const CompiledData::Object *namedObject = objectAt(*namedObjectIndexPtr);
+        namedObjectCache.add(runtimeStrings[namedObject->idNameIndex], namedObject->id);
+    }
+    return *namedObjectsPerComponentCache.insert(componentObjectIndex, namedObjectCache);
+}
+
+void ExecutableCompilationUnit::finalizeCompositeType(QQmlEnginePrivate *qmlEngine)
+{
+    this->qmlEngine = qmlEngine;
+
+    // Add to type registry of composites
+    if (propertyCaches.needsVMEMetaObject(/*root object*/0)) {
+        QQmlMetaType::registerInternalCompositeType(this);
+        qmlEngine->registerInternalCompositeType(this);
+    } else {
+        const QV4::CompiledData::Object *obj = objectAt(/*root object*/0);
+        auto *typeRef = resolvedTypes.value(obj->inheritedTypeNameIndex);
+        Q_ASSERT(typeRef);
+        if (typeRef->compilationUnit) {
+            metaTypeId = typeRef->compilationUnit->metaTypeId;
+            listMetaTypeId = typeRef->compilationUnit->listMetaTypeId;
+        } else {
+            metaTypeId = typeRef->type.typeId();
+            listMetaTypeId = typeRef->type.qListTypeId();
+        }
+    }
+
+    // Collect some data for instantiation later.
+    int bindingCount = 0;
+    int parserStatusCount = 0;
+    int objectCount = 0;
+    for (quint32 i = 0, count = this->objectCount(); i < count; ++i) {
+        const QV4::CompiledData::Object *obj = objectAt(i);
+        bindingCount += obj->nBindings;
+        if (auto *typeRef = resolvedTypes.value(obj->inheritedTypeNameIndex)) {
+            if (typeRef->type.isValid()) {
+                if (typeRef->type.parserStatusCast() != -1)
+                    ++parserStatusCount;
+            }
+            ++objectCount;
+            if (typeRef->compilationUnit) {
+                bindingCount += typeRef->compilationUnit->totalBindingsCount;
+                parserStatusCount += typeRef->compilationUnit->totalParserStatusCount;
+                objectCount += typeRef->compilationUnit->totalObjectCount;
+            }
+        }
+    }
+
+    totalBindingsCount = bindingCount;
+    totalParserStatusCount = parserStatusCount;
+    totalObjectCount = objectCount;
+}
+
+bool ExecutableCompilationUnit::verifyChecksum(const CompiledData::DependentTypesHasher &dependencyHasher) const
+{
+    if (!dependencyHasher) {
+        for (size_t i = 0; i < sizeof(data->dependencyMD5Checksum); ++i) {
+            if (data->dependencyMD5Checksum[i] != 0)
+                return false;
+        }
+        return true;
+    }
+    const QByteArray checksum = dependencyHasher();
+    return checksum.size() == sizeof(data->dependencyMD5Checksum)
+            && memcmp(data->dependencyMD5Checksum, checksum.constData(),
+                      sizeof(data->dependencyMD5Checksum)) == 0;
+}
+
+QStringList ExecutableCompilationUnit::moduleRequests() const
+{
+    QStringList requests;
+    requests.reserve(data->moduleRequestTableSize);
+    for (uint i = 0; i < data->moduleRequestTableSize; ++i)
+        requests << stringAt(data->moduleRequestTable()[i]);
+    return requests;
+}
+
+Heap::Module *ExecutableCompilationUnit::instantiate(ExecutionEngine *engine)
+{
+    if (isESModule() && module())
+        return module();
+
+    if (data->indexOfRootFunction < 0)
+        return nullptr;
+
+    if (!this->engine)
+        linkToEngine(engine);
+
+    Scope scope(engine);
+    Scoped<Module> module(scope, engine->memoryManager->allocate<Module>(engine, this));
+
+    if (isESModule())
+        setModule(module->d());
+
+    for (const QString &request: moduleRequests()) {
+        auto dependentModuleUnit = engine->loadModule(QUrl(request), this);
+        if (engine->hasException)
+            return nullptr;
+        dependentModuleUnit->instantiate(engine);
+    }
+
+    ScopedString importName(scope);
+
+    const uint importCount = data->importEntryTableSize;
+    if (importCount > 0) {
+        imports = new const Value *[importCount];
+        memset(imports, 0, importCount * sizeof(Value *));
+    }
+    for (uint i = 0; i < importCount; ++i) {
+        const CompiledData::ImportEntry &entry = data->importEntryTable()[i];
+        auto dependentModuleUnit = engine->loadModule(urlAt(entry.moduleRequest), this);
+        importName = runtimeStrings[entry.importName];
+        const Value *valuePtr = dependentModuleUnit->resolveExport(importName);
+        if (!valuePtr) {
+            QString referenceErrorMessage = QStringLiteral("Unable to resolve import reference ");
+            referenceErrorMessage += importName->toQString();
+            engine->throwReferenceError(referenceErrorMessage, fileName(), entry.location.line, entry.location.column);
+            return nullptr;
+        }
+        imports[i] = valuePtr;
+    }
+
+    for (uint i = 0; i < data->indirectExportEntryTableSize; ++i) {
+        const CompiledData::ExportEntry &entry = data->indirectExportEntryTable()[i];
+        auto dependentModuleUnit = engine->loadModule(urlAt(entry.moduleRequest), this);
+        if (!dependentModuleUnit)
+            return nullptr;
+
+        ScopedString importName(scope, runtimeStrings[entry.importName]);
+        if (!dependentModuleUnit->resolveExport(importName)) {
+            QString referenceErrorMessage = QStringLiteral("Unable to resolve re-export reference ");
+            referenceErrorMessage += importName->toQString();
+            engine->throwReferenceError(referenceErrorMessage, fileName(), entry.location.line, entry.location.column);
+            return nullptr;
+        }
+    }
+
+    return module->d();
+}
+
+const Value *ExecutableCompilationUnit::resolveExportRecursively(
+        QV4::String *exportName, QVector<ResolveSetEntry> *resolveSet)
+{
+    if (!module())
+        return nullptr;
+
+    for (const auto &entry: *resolveSet)
+        if (entry.module == this && entry.exportName->isEqualTo(exportName))
+            return nullptr;
+
+    (*resolveSet) << ResolveSetEntry(this, exportName);
+
+    if (exportName->toQString() == QLatin1String("*"))
+        return &module()->self;
+
+    Scope scope(engine);
+
+    if (auto localExport = lookupNameInExportTable(
+                data->localExportEntryTable(), data->localExportEntryTableSize, exportName)) {
+        ScopedString localName(scope, runtimeStrings[localExport->localName]);
+        uint index = module()->scope->internalClass->indexOfValueOrGetter(localName->toPropertyKey());
+        if (index == UINT_MAX)
+            return nullptr;
+        if (index >= module()->scope->locals.size)
+            return imports[index - module()->scope->locals.size];
+        return &module()->scope->locals[index];
+    }
+
+    if (auto indirectExport = lookupNameInExportTable(
+                data->indirectExportEntryTable(), data->indirectExportEntryTableSize, exportName)) {
+        auto dependentModuleUnit = engine->loadModule(urlAt(indirectExport->moduleRequest), this);
+        if (!dependentModuleUnit)
+            return nullptr;
+        ScopedString importName(scope, runtimeStrings[indirectExport->importName]);
+        return dependentModuleUnit->resolveExportRecursively(importName, resolveSet);
+    }
+
+
+    if (exportName->toQString() == QLatin1String("default"))
+        return nullptr;
+
+    const Value *starResolution = nullptr;
+
+    for (uint i = 0; i < data->starExportEntryTableSize; ++i) {
+        const CompiledData::ExportEntry &entry = data->starExportEntryTable()[i];
+        auto dependentModuleUnit = engine->loadModule(urlAt(entry.moduleRequest), this);
+        if (!dependentModuleUnit)
+            return nullptr;
+
+        const Value *resolution = dependentModuleUnit->resolveExportRecursively(exportName, resolveSet);
+        // ### handle ambiguous
+        if (resolution) {
+            if (!starResolution) {
+                starResolution = resolution;
+                continue;
+            }
+            if (resolution != starResolution)
+                return nullptr;
+        }
+    }
+
+    return starResolution;
+}
+
+const CompiledData::ExportEntry *ExecutableCompilationUnit::lookupNameInExportTable(
+        const CompiledData::ExportEntry *firstExportEntry, int tableSize, QV4::String *name) const
+{
+    const CompiledData::ExportEntry *lastExportEntry = firstExportEntry + tableSize;
+    auto matchingExport = std::lower_bound(firstExportEntry, lastExportEntry, name, [this](const CompiledData::ExportEntry &lhs, QV4::String *name) {
+        return stringAt(lhs.exportName) < name->toQString();
+    });
+    if (matchingExport == lastExportEntry || stringAt(matchingExport->exportName) != name->toQString())
+        return nullptr;
+    return matchingExport;
+}
+
+void ExecutableCompilationUnit::getExportedNamesRecursively(
+        QStringList *names, QVector<const ExecutableCompilationUnit*> *exportNameSet,
+        bool includeDefaultExport) const
+{
+    if (exportNameSet->contains(this))
+        return;
+    exportNameSet->append(this);
+
+    const auto append = [names, includeDefaultExport](const QString &name) {
+        if (!includeDefaultExport && name == QLatin1String("default"))
+            return;
+        names->append(name);
+    };
+
+    for (uint i = 0; i < data->localExportEntryTableSize; ++i) {
+        const CompiledData::ExportEntry &entry = data->localExportEntryTable()[i];
+        append(stringAt(entry.exportName));
+    }
+
+    for (uint i = 0; i < data->indirectExportEntryTableSize; ++i) {
+        const CompiledData::ExportEntry &entry = data->indirectExportEntryTable()[i];
+        append(stringAt(entry.exportName));
+    }
+
+    for (uint i = 0; i < data->starExportEntryTableSize; ++i) {
+        const CompiledData::ExportEntry &entry = data->starExportEntryTable()[i];
+        auto dependentModuleUnit = engine->loadModule(urlAt(entry.moduleRequest), this);
+        if (!dependentModuleUnit)
+            return;
+        dependentModuleUnit->getExportedNamesRecursively(names, exportNameSet, /*includeDefaultExport*/false);
+    }
+}
+
+void ExecutableCompilationUnit::evaluate()
+{
+    QV4::Scope scope(engine);
+    QV4::Scoped<Module> mod(scope, module());
+    mod->evaluate();
+}
+
+void ExecutableCompilationUnit::evaluateModuleRequests()
+{
+    for (const QString &request: moduleRequests()) {
+        auto dependentModuleUnit = engine->loadModule(QUrl(request), this);
+        if (engine->hasException)
+            return;
+        dependentModuleUnit->evaluate();
+        if (engine->hasException)
+            return;
+    }
+}
+
+bool ExecutableCompilationUnit::loadFromDisk(const QUrl &url, const QDateTime &sourceTimeStamp, QString *errorString)
+{
+    if (!QQmlFile::isLocalFile(url)) {
+        *errorString = QStringLiteral("File has to be a local file.");
+        return false;
+    }
+
+    const QString sourcePath = QQmlFile::urlToLocalFileOrQrc(url);
+    QScopedPointer<CompilationUnitMapper> cacheFile(new CompilationUnitMapper());
+
+    const QStringList cachePaths = { sourcePath + QLatin1Char('c'), localCacheFilePath(url) };
+    for (const QString &cachePath : cachePaths) {
+        CompiledData::Unit *mappedUnit = cacheFile->open(cachePath, sourceTimeStamp, errorString);
+        if (!mappedUnit)
+            continue;
+
+        const CompiledData::Unit * const oldDataPtr
+                = (data && !(data->flags & QV4::CompiledData::Unit::StaticData)) ? data
+                                                                                     : nullptr;
+        const CompiledData::Unit *oldData = data;
+        auto dataPtrRevert = qScopeGuard([this, oldData](){
+            setUnitData(oldData);
+        });
+        setUnitData(mappedUnit);
+
+        if (data->sourceFileIndex != 0
+            && sourcePath != QQmlFile::urlToLocalFileOrQrc(stringAt(data->sourceFileIndex))) {
+            *errorString = QStringLiteral("QML source file has moved to a different location.");
+            continue;
+        }
+
+        dataPtrRevert.dismiss();
+        free(const_cast<CompiledData::Unit*>(oldDataPtr));
+        backingFile.reset(cacheFile.take());
+        return true;
+    }
+
+    return false;
+}
+
+bool ExecutableCompilationUnit::saveToDisk(const QUrl &unitUrl, QString *errorString)
+{
+    if (data->sourceTimeStamp == 0) {
+        *errorString = QStringLiteral("Missing time stamp for source file");
+        return false;
+    }
+
+    if (!QQmlFile::isLocalFile(unitUrl)) {
+        *errorString = QStringLiteral("File has to be a local file.");
+        return false;
+    }
+
+    return CompilationUnit::saveToDisk(localCacheFilePath(unitUrl), errorString);
+}
+
+/*!
+Returns the property cache, if one alread exists.  The cache is not referenced.
+*/
+QQmlRefPointer<QQmlPropertyCache> ResolvedTypeReference::propertyCache() const
+{
+    if (type.isValid())
+        return typePropertyCache;
+    else
+        return compilationUnit->rootPropertyCache();
+}
+
+/*!
+Returns the property cache, creating one if it doesn't already exist.  The cache is not referenced.
+*/
+QQmlRefPointer<QQmlPropertyCache> ResolvedTypeReference::createPropertyCache(QQmlEngine *engine)
+{
+    if (typePropertyCache) {
+        return typePropertyCache;
+    } else if (type.isValid()) {
+        typePropertyCache = QQmlEnginePrivate::get(engine)->cache(type.metaObject(), minorVersion);
+        return typePropertyCache;
+    } else {
+        return compilationUnit->rootPropertyCache();
+    }
+}
+
+bool ResolvedTypeReference::addToHash(QCryptographicHash *hash, QQmlEngine *engine)
+{
+    if (type.isValid()) {
+        bool ok = false;
+        hash->addData(createPropertyCache(engine)->checksum(&ok));
+        return ok;
+    }
+    if (!compilationUnit)
+        return false;
+    hash->addData(compilationUnit->data->md5Checksum,
+                  sizeof(compilationUnit->data->md5Checksum));
+    return true;
+}
+
+template <typename T>
+bool qtTypeInherits(const QMetaObject *mo) {
+    while (mo) {
+        if (mo == &T::staticMetaObject)
+            return true;
+        mo = mo->superClass();
+    }
+    return false;
+}
+
+void ResolvedTypeReference::doDynamicTypeCheck()
+{
+    const QMetaObject *mo = nullptr;
+    if (typePropertyCache)
+        mo = typePropertyCache->firstCppMetaObject();
+    else if (type.isValid())
+        mo = type.metaObject();
+    else if (compilationUnit)
+        mo = compilationUnit->rootPropertyCache()->firstCppMetaObject();
+    isFullyDynamicType = qtTypeInherits<QQmlPropertyMap>(mo);
+}
+
+bool ResolvedTypeReferenceMap::addToHash(QCryptographicHash *hash, QQmlEngine *engine) const
+{
+    for (auto it = constBegin(), end = constEnd(); it != end; ++it) {
+        if (!it.value()->addToHash(hash, engine))
+            return false;
+    }
+
+    return true;
+}
+
+QString ExecutableCompilationUnit::bindingValueAsString(const CompiledData::Binding *binding) const
+{
+    using namespace CompiledData;
+    switch (binding->type) {
+    case Binding::Type_Script:
+    case Binding::Type_String:
+        return stringAt(binding->stringIndex);
+    case Binding::Type_Null:
+        return QStringLiteral("null");
+    case Binding::Type_Boolean:
+        return binding->value.b ? QStringLiteral("true") : QStringLiteral("false");
+    case Binding::Type_Number:
+        return QString::number(bindingValueAsNumber(binding));
+    case Binding::Type_Invalid:
+        return QString();
+#if !QT_CONFIG(translation)
+    case Binding::Type_TranslationById:
+    case Binding::Type_Translation:
+        return unit->stringAt(
+                unit->data->translations()[binding->value.translationDataIndex].stringIndex);
+#else
+    case Binding::Type_TranslationById: {
+        const TranslationData &translation
+                = data->translations()[binding->value.translationDataIndex];
+        QByteArray id = stringAt(translation.stringIndex).toUtf8();
+        return qtTrId(id.constData(), translation.number);
+    }
+    case Binding::Type_Translation: {
+        const TranslationData &translation
+                = data->translations()[binding->value.translationDataIndex];
+        // This code must match that in the qsTr() implementation
+        const QString &path = fileName();
+        int lastSlash = path.lastIndexOf(QLatin1Char('/'));
+        QStringRef context = (lastSlash > -1) ? path.midRef(lastSlash + 1, path.length() - lastSlash - 5)
+                                              : QStringRef();
+        QByteArray contextUtf8 = context.toUtf8();
+        QByteArray comment = stringAt(translation.commentIndex).toUtf8();
+        QByteArray text = stringAt(translation.stringIndex).toUtf8();
+        return QCoreApplication::translate(contextUtf8.constData(), text.constData(),
+                                           comment.constData(), translation.number);
+    }
+#endif
+    default:
+        break;
+    }
+    return QString();
+}
+
+QString ExecutableCompilationUnit::bindingValueAsScriptString(
+        const CompiledData::Binding *binding) const
+{
+    return (binding->type == CompiledData::Binding::Type_String)
+            ? CompiledData::Binding::escapedString(stringAt(binding->stringIndex))
+            : bindingValueAsString(binding);
+}
+
+} // namespace QV4
+
+QT_END_NAMESPACE
diff --git a/src/qml/compiler/qv4executablecompilationunit_p.h b/src/qml/compiler/qv4executablecompilationunit_p.h
new file mode 100644
index 0000000000..4e3aadf28a
--- /dev/null
+++ b/src/qml/compiler/qv4executablecompilationunit_p.h
@@ -0,0 +1,324 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the tools applications of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QV4EXECUTABLECOMPILATIONUNIT_P_H
+#define QV4EXECUTABLECOMPILATIONUNIT_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <private/qv4compileddata_p.h>
+#include <private/qqmlrefcount_p.h>
+#include <private/qintrusivelist_p.h>
+#include <private/qqmlpropertycachevector_p.h>
+#include <private/qqmltype_p.h>
+
+QT_BEGIN_NAMESPACE
+
+class QQmlEnginePrivate;
+namespace QV4 {
+
+class CompilationUnitMapper;
+struct ResolvedTypeReference;
+// map from name index
+// While this could be a hash, a map is chosen here to provide a stable
+// order, which is used to calculating a check-sum on dependent meta-objects.
+struct ResolvedTypeReferenceMap: public QMap<int, ResolvedTypeReference*>
+{
+    bool addToHash(QCryptographicHash *hash, QQmlEngine *engine) const;
+};
+
+class Q_QML_PRIVATE_EXPORT ExecutableCompilationUnit final: public CompiledData::CompilationUnit,
+                                                            public QQmlRefCount
+{
+    Q_DISABLE_COPY_MOVE(ExecutableCompilationUnit)
+public:
+    friend class QQmlRefPointer<ExecutableCompilationUnit>;
+
+    static QQmlRefPointer<ExecutableCompilationUnit> create(
+            CompiledData::CompilationUnit &&compilationUnit)
+    {
+        return QQmlRefPointer<ExecutableCompilationUnit>(
+                new ExecutableCompilationUnit(std::move(compilationUnit)),
+                QQmlRefPointer<ExecutableCompilationUnit>::Adopt);
+    }
+
+    static QQmlRefPointer<ExecutableCompilationUnit> create()
+    {
+        return QQmlRefPointer<ExecutableCompilationUnit>(
+                new ExecutableCompilationUnit,
+                QQmlRefPointer<ExecutableCompilationUnit>::Adopt);
+    }
+
+    QIntrusiveListNode nextCompilationUnit;
+    ExecutionEngine *engine = nullptr;
+    QQmlEnginePrivate *qmlEngine = nullptr; // only used in QML environment for composite types, not in plain QJSEngine case.
+
+    // url() and fileName() shall be used to load the actual QML/JS code or to show errors or
+    // warnings about that code. They include any potential URL interceptions and thus represent the
+    // "physical" location of the code.
+    //
+    // finalUrl() and finalUrlString() shall be used to resolve further URLs referred to in the code
+    // They are _not_ intercepted and thus represent the "logical" name for the code.
+
+    QUrl url() const { if (m_url.isNull) m_url = QUrl(fileName()); return m_url; }
+    QUrl finalUrl() const
+    {
+        if (m_finalUrl.isNull)
+            m_finalUrl = QUrl(finalUrlString());
+        return m_finalUrl;
+    }
+
+    QV4::Lookup *runtimeLookups = nullptr;
+    QVector<QV4::Function *> runtimeFunctions;
+    QVector<QV4::Heap::InternalClass *> runtimeBlocks;
+    mutable QVector<QV4::Heap::Object *> templateObjects;
+    mutable QQmlNullableValue<QUrl> m_url;
+    mutable QQmlNullableValue<QUrl> m_finalUrl;
+
+    // QML specific fields
+    QQmlPropertyCacheVector propertyCaches;
+    QQmlRefPointer<QQmlPropertyCache> rootPropertyCache() const { return propertyCaches.at(/*root object*/0); }
+
+    QQmlRefPointer<QQmlTypeNameCache> typeNameCache;
+
+    // index is object index. This allows fast access to the
+    // property data when initializing bindings, avoiding expensive
+    // lookups by string (property name).
+    QVector<CompiledData::BindingPropertyData> bindingPropertyDataPerObject;
+
+    // mapping from component object index (CompiledData::Unit object index that points to component) to identifier hash of named objects
+    // this is initialized on-demand by QQmlContextData
+    QHash<int, IdentifierHash> namedObjectsPerComponentCache;
+    inline IdentifierHash namedObjectsPerComponent(int componentObjectIndex);
+
+    void finalizeCompositeType(QQmlEnginePrivate *qmlEngine);
+
+    int totalBindingsCount = 0; // Number of bindings used in this type
+    int totalParserStatusCount = 0; // Number of instantiated types that are QQmlParserStatus subclasses
+    int totalObjectCount = 0; // Number of objects explicitly instantiated
+
+    QVector<QQmlRefPointer<QQmlScriptData>> dependentScripts;
+    ResolvedTypeReferenceMap resolvedTypes;
+    ResolvedTypeReference *resolvedType(int id) const { return resolvedTypes.value(id); }
+
+    bool verifyChecksum(const CompiledData::DependentTypesHasher &dependencyHasher) const;
+
+    int metaTypeId = -1;
+    int listMetaTypeId = -1;
+    bool isRegisteredWithEngine = false;
+
+    QScopedPointer<CompilationUnitMapper> backingFile;
+
+    // --- interface for QQmlPropertyCacheCreator
+    using CompiledObject = CompiledData::Object;
+    using CompiledFunction = CompiledData::Function;
+
+    int objectCount() const { return qmlData->nObjects; }
+    const CompiledObject *objectAt(int index) const
+    {
+        return qmlData->objectAt(index);
+    }
+
+    int importCount() const { return qmlData->nImports; }
+    const CompiledData::Import *importAt(int index) const
+    {
+        return qmlData->importAt(index);
+    }
+
+    Heap::Object *templateObjectAt(int index) const;
+
+    struct FunctionIterator
+    {
+        FunctionIterator(const CompiledData::Unit *unit, const CompiledObject *object, int index)
+            : unit(unit), object(object), index(index) {}
+        const CompiledData::Unit *unit;
+        const CompiledObject *object;
+        int index;
+
+        const CompiledFunction *operator->() const
+        {
+            return unit->functionAt(object->functionOffsetTable()[index]);
+        }
+
+        void operator++() { ++index; }
+        bool operator==(const FunctionIterator &rhs) const { return index == rhs.index; }
+        bool operator!=(const FunctionIterator &rhs) const { return index != rhs.index; }
+    };
+
+    FunctionIterator objectFunctionsBegin(const CompiledObject *object) const
+    {
+        return FunctionIterator(data, object, 0);
+    }
+
+    FunctionIterator objectFunctionsEnd(const CompiledObject *object) const
+    {
+        return FunctionIterator(data, object, object->nFunctions);
+    }
+
+    bool isESModule() const
+    {
+        return data->flags & CompiledData::Unit::IsESModule;
+    }
+
+    bool isSharedLibrary() const
+    {
+        return data->flags & CompiledData::Unit::IsSharedLibrary;
+    }
+
+    QStringList moduleRequests() const;
+    Heap::Module *instantiate(ExecutionEngine *engine);
+    const Value *resolveExport(QV4::String *exportName)
+    {
+        QVector<ResolveSetEntry> resolveSet;
+        return resolveExportRecursively(exportName, &resolveSet);
+    }
+
+    QStringList exportedNames() const
+    {
+        QStringList names;
+        QVector<const ExecutableCompilationUnit*> exportNameSet;
+        getExportedNamesRecursively(&names, &exportNameSet);
+        names.sort();
+        auto last = std::unique(names.begin(), names.end());
+        names.erase(last, names.end());
+        return names;
+    }
+
+    void evaluate();
+    void evaluateModuleRequests();
+
+    QV4::Function *linkToEngine(QV4::ExecutionEngine *engine);
+    void unlink();
+
+    void markObjects(MarkStack *markStack);
+
+    bool loadFromDisk(const QUrl &url, const QDateTime &sourceTimeStamp, QString *errorString);
+
+    static QString localCacheFilePath(const QUrl &url);
+    bool saveToDisk(const QUrl &unitUrl, QString *errorString);
+
+    QString bindingValueAsString(const CompiledData::Binding *binding) const;
+    QString bindingValueAsScriptString(const CompiledData::Binding *binding) const;
+    double bindingValueAsNumber(const CompiledData::Binding *binding) const
+    {
+        if (binding->type != CompiledData::Binding::Type_Number)
+            return 0.0;
+        return constants[binding->value.constantValueIndex].doubleValue();
+    }
+
+protected:
+    quint32 totalStringCount() const
+    { return data->stringTableSize; }
+
+private:
+    struct ResolveSetEntry
+    {
+        ResolveSetEntry() {}
+        ResolveSetEntry(ExecutableCompilationUnit *module, QV4::String *exportName)
+            : module(module), exportName(exportName) {}
+        ExecutableCompilationUnit *module = nullptr;
+        QV4::String *exportName = nullptr;
+    };
+
+    ExecutableCompilationUnit();
+    ExecutableCompilationUnit(CompiledData::CompilationUnit &&compilationUnit);
+    ~ExecutableCompilationUnit();
+
+    const Value *resolveExportRecursively(QV4::String *exportName,
+                                          QVector<ResolveSetEntry> *resolveSet);
+
+    QUrl urlAt(int index) const { return QUrl(stringAt(index)); }
+
+    Q_NEVER_INLINE IdentifierHash createNamedObjectsPerComponent(int componentObjectIndex);
+    const CompiledData::ExportEntry *lookupNameInExportTable(
+            const CompiledData::ExportEntry *firstExportEntry, int tableSize,
+            QV4::String *name) const;
+
+    void getExportedNamesRecursively(
+            QStringList *names, QVector<const ExecutableCompilationUnit *> *exportNameSet,
+            bool includeDefaultExport = true) const;
+};
+
+struct ResolvedTypeReference
+{
+    ResolvedTypeReference()
+        : majorVersion(0)
+          , minorVersion(0)
+          , isFullyDynamicType(false)
+    {}
+
+    QQmlType type;
+    QQmlRefPointer<QQmlPropertyCache> typePropertyCache;
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> compilationUnit;
+
+    int majorVersion;
+    int minorVersion;
+    // Types such as QQmlPropertyMap can add properties dynamically at run-time and
+    // therefore cannot have a property cache installed when instantiated.
+    bool isFullyDynamicType;
+
+    QQmlRefPointer<QQmlPropertyCache> propertyCache() const;
+    QQmlRefPointer<QQmlPropertyCache> createPropertyCache(QQmlEngine *);
+    bool addToHash(QCryptographicHash *hash, QQmlEngine *engine);
+
+    void doDynamicTypeCheck();
+};
+
+IdentifierHash ExecutableCompilationUnit::namedObjectsPerComponent(int componentObjectIndex)
+{
+    auto it = namedObjectsPerComponentCache.find(componentObjectIndex);
+    if (Q_UNLIKELY(it == namedObjectsPerComponentCache.end()))
+        return createNamedObjectsPerComponent(componentObjectIndex);
+    return *it;
+}
+
+} // namespace QV4
+
+QT_END_NAMESPACE
+
+#endif // QV4EXECUTABLECOMPILATIONUNIT_P_H
diff --git a/src/qml/compiler/qv4instr_moth.cpp b/src/qml/compiler/qv4instr_moth.cpp
index 5148154a6a..8a9bd66103 100644
--- a/src/qml/compiler/qv4instr_moth.cpp
+++ b/src/qml/compiler/qv4instr_moth.cpp
@@ -39,7 +39,7 @@
 
 #include "qv4instr_moth_p.h"
 #include <private/qv4compileddata_p.h>
-#include <private/qv4stackframe_p.h>
+#include <private/qv4calldata_p.h>
 
 using namespace QV4;
 using namespace QV4::Moth;
@@ -56,9 +56,7 @@ int InstrInfo::size(Instr::Type type)
 
 static QByteArray alignedNumber(int n) {
     QByteArray number = QByteArray::number(n);
-    while (number.size() < 8)
-        number.prepend(' ');
-    return number;
+    return number.prepend(8 - number.size(), ' ');
 }
 
 static QByteArray alignedLineNumber(int line) {
@@ -83,25 +81,6 @@ static QByteArray rawBytes(const char *data, int n)
     return ba;
 }
 
-static QString toString(QV4::ReturnedValue v)
-{
-#ifdef V4_BOOTSTRAP
-    return QStringLiteral("string-const(%1)").arg(v);
-#else // !V4_BOOTSTRAP
-    Value val = Value::fromReturnedValue(v);
-    QString result;
-    if (val.isInt32())
-        result = QLatin1String("int ");
-    else if (val.isDouble())
-        result = QLatin1String("double ");
-    if (val.isEmpty())
-        result += QLatin1String("empty");
-    else
-        result += val.toQStringNoThrow();
-    return result;
-#endif // V4_BOOTSTRAP
-}
-
 #define ABSOLUTE_OFFSET() \
     (code - start + offset)
 
@@ -128,16 +107,6 @@ const int InstrInfo::argumentCount[] = {
     FOR_EACH_MOTH_INSTR_ALL(MOTH_COLLECT_NARGS)
 };
 
-
-void dumpConstantTable(const Value *constants, uint count)
-{
-    QDebug d = qDebug();
-    d.nospace();
-    for (uint i = 0; i < count; ++i)
-        d << alignedNumber(int(i)).constData() << ":    "
-          << toString(constants[i].asReturnedValue()).toUtf8().constData() << "\n";
-}
-
 QString dumpRegister(int reg, int nFormals)
 {
     Q_STATIC_ASSERT(offsetof(CallData, function) == 0);
diff --git a/src/qml/compiler/qv4instr_moth_p.h b/src/qml/compiler/qv4instr_moth_p.h
index 35a5fdfba5..5338583164 100644
--- a/src/qml/compiler/qv4instr_moth_p.h
+++ b/src/qml/compiler/qv4instr_moth_p.h
@@ -51,7 +51,6 @@
 // We mean it.
 //
 #include <private/qv4global_p.h>
-#include <private/qv4value_p.h>
 #include <private/qv4runtime_p.h>
 #include <private/qv4compileddata_p.h> // for CompiledData::CodeOffsetToLine used by the dumper
 #include <qendian.h>
@@ -534,7 +533,6 @@ inline bool operator!=(const StackSlot &l, const StackSlot &r) { return l.stackS
 
 // When making changes to the instructions, make sure to bump QV4_DATA_STRUCTURE_VERSION in qv4compileddata_p.h
 
-void dumpConstantTable(const Value *constants, uint count);
 void dumpBytecode(const char *bytecode, int len, int nLocals, int nFormals, int startLine = 1,
                   const QVector<CompiledData::CodeOffsetToLine> &lineNumberMapping = QVector<CompiledData::CodeOffsetToLine>());
 inline void dumpBytecode(const QByteArray &bytecode, int nLocals, int nFormals, int startLine = 1,
diff --git a/src/qml/configure.json b/src/qml/configure.json
index 2f88aef1fb..9313e4594b 100644
--- a/src/qml/configure.json
+++ b/src/qml/configure.json
@@ -90,8 +90,8 @@
             "purpose": "Provides a JIT for QML and JavaScript",
             "section": "QML",
             "condition": [
-                "   (arch.i386   && tests.pointer_32bit)
-                 || (arch.x86_64 && tests.pointer_64bit)
+                "   (arch.i386   && tests.pointer_32bit && features.sse2)
+                 || (arch.x86_64 && tests.pointer_64bit && features.sse2)
                  || (arch.arm    && tests.pointer_32bit && tests.arm_fp && tests.arm_thumb
                      && (config.linux || config.ios || config.tvos || config.qnx))
                  || (arch.arm64  && tests.pointer_64bit && tests.arm_fp
diff --git a/src/qml/debugger/qqmlprofiler_p.h b/src/qml/debugger/qqmlprofiler_p.h
index d01e2bc429..d3eedab1c6 100644
--- a/src/qml/debugger/qqmlprofiler_p.h
+++ b/src/qml/debugger/qqmlprofiler_p.h
@@ -171,10 +171,11 @@ public:
             : Location(ref->sourceLocation()), locationType(Binding), sent(false)
         {
             function = ref;
-            function->compilationUnit->addref();
+            function->executableCompilationUnit()->addref();
         }
 
-        RefLocation(QV4::CompiledData::CompilationUnit *ref, const QUrl &url, const QV4::CompiledData::Object *obj, const QString &type)
+        RefLocation(QV4::ExecutableCompilationUnit *ref, const QUrl &url,
+                    const QV4::CompiledData::Object *obj, const QString &type)
             : Location(QQmlSourceLocation(type, obj->location.line, obj->location.column), url),
               locationType(Creating), sent(false)
         {
@@ -230,7 +231,7 @@ public:
 
             switch (locationType) {
             case Binding:
-                function->compilationUnit->addref();
+                function->executableCompilationUnit()->addref();
                 break;
             case Creating:
                 unit->addref();
@@ -254,7 +255,7 @@ public:
 
             switch (locationType) {
             case Binding:
-                function->compilationUnit->release();
+                function->executableCompilationUnit()->release();
                 break;
             case Creating:
                 unit->release();
@@ -284,7 +285,7 @@ public:
         RangeType locationType;
         union {
             QV4::Function *function;
-            QV4::CompiledData::CompilationUnit *unit;
+            QV4::ExecutableCompilationUnit *unit;
             QQmlBoundSignalExpression *boundSignal;
             QQmlDataBlob *blob;
             void *something;
@@ -356,7 +357,7 @@ public:
     }
 
     void updateCreating(const QV4::CompiledData::Object *obj,
-                        QV4::CompiledData::CompilationUnit *ref,
+                        QV4::ExecutableCompilationUnit *ref,
                         const QUrl &url, const QString &type)
     {
         quintptr locationId(id(obj));
@@ -492,7 +493,7 @@ public:
         Q_QML_PROFILE(QQmlProfilerDefinitions::ProfileCreating, profiler, endRange<QQmlProfilerDefinitions::Creating>());
     }
 
-    void update(QV4::CompiledData::CompilationUnit *ref, const QV4::CompiledData::Object *obj,
+    void update(QV4::ExecutableCompilationUnit *ref, const QV4::CompiledData::Object *obj,
                 const QString &typeName, const QUrl &url)
     {
         profiler->updateCreating(obj, ref, url, typeName);
diff --git a/src/qml/doc/src/qmllanguageref/typesystem/basictypes.qdoc b/src/qml/doc/src/qmllanguageref/typesystem/basictypes.qdoc
index c4c1b61693..5144fe219e 100644
--- a/src/qml/doc/src/qmllanguageref/typesystem/basictypes.qdoc
+++ b/src/qml/doc/src/qmllanguageref/typesystem/basictypes.qdoc
@@ -44,6 +44,10 @@ Basic types can be used to refer to:
 \li A value that contains a simple set of property-value pairs (e.g. \l size refers to a value with \c width and \c height attributes)
 \endlist
 
+When a variable or property holds a basic type and it is assigned to another
+variable or property, then a copy of the value is made. In JavaScript, this
+value is called a primitive value.
+
 \sa {qtqml-typesystem-topic.html}{The QML Type System}
 
 
diff --git a/src/qml/jit/qv4assemblercommon_p.h b/src/qml/jit/qv4assemblercommon_p.h
index f305213ce2..b9f71b7bd9 100644
--- a/src/qml/jit/qv4assemblercommon_p.h
+++ b/src/qml/jit/qv4assemblercommon_p.h
@@ -449,7 +449,7 @@ public:
     // r6 is used by MacroAssemblerARMv7
     static const RegisterID JSStackFrameRegister     = JSC::ARMRegisters::r8;
     static const RegisterID CppStackFrameRegister    = JSC::ARMRegisters::r10;
-#if CPU(ARM_THUMB2) || defined(V4_BOOTSTRAP)
+#if CPU(ARM_THUMB2)
     static const RegisterID FramePointerRegister     = JSC::ARMRegisters::r7;
     static const RegisterID EngineRegister           = JSC::ARMRegisters::r11;
 #else // Thumbs down
diff --git a/src/qml/jsapi/qjsengine.cpp b/src/qml/jsapi/qjsengine.cpp
index 45ea79d31a..7bf2a4d004 100644
--- a/src/qml/jsapi/qjsengine.cpp
+++ b/src/qml/jsapi/qjsengine.cpp
@@ -41,7 +41,6 @@
 #include "qjsengine_p.h"
 #include "qjsvalue.h"
 #include "qjsvalue_p.h"
-#include "private/qv8engine_p.h"
 
 #include "private/qv4engine_p.h"
 #include "private/qv4mm_p.h"
@@ -348,7 +347,6 @@ QJSEngine::QJSEngine(QObject *parent)
     : QObject(*new QJSEnginePrivate, parent)
     , m_v4Engine(new QV4::ExecutionEngine(this))
 {
-    m_v4Engine->v8Engine = new QV8Engine(m_v4Engine);
     checkForApplicationInstance();
 
     QJSEnginePrivate::addToDebugServer(this);
@@ -361,7 +359,6 @@ QJSEngine::QJSEngine(QJSEnginePrivate &dd, QObject *parent)
     : QObject(dd, parent)
     , m_v4Engine(new QV4::ExecutionEngine(this))
 {
-    m_v4Engine->v8Engine = new QV8Engine(m_v4Engine);
     checkForApplicationInstance();
 }
 
@@ -375,7 +372,6 @@ QJSEngine::QJSEngine(QJSEnginePrivate &dd, QObject *parent)
 QJSEngine::~QJSEngine()
 {
     QJSEnginePrivate::removeFromDebugServer(this);
-    delete m_v4Engine->v8Engine;
     delete m_v4Engine;
 }
 
diff --git a/src/qml/jsruntime/jsruntime.pri b/src/qml/jsruntime/jsruntime.pri
index a24ee0a188..e6f1079aa7 100644
--- a/src/qml/jsruntime/jsruntime.pri
+++ b/src/qml/jsruntime/jsruntime.pri
@@ -3,6 +3,7 @@ INCLUDEPATH += $$OUT_PWD
 
 !qmldevtools_build {
 SOURCES += \
+    $$PWD/qv4engine.cpp \
     $$PWD/qv4context.cpp \
     $$PWD/qv4persistent.cpp \
     $$PWD/qv4lookup.cpp \
@@ -36,13 +37,13 @@ SOURCES += \
     $$PWD/qv4reflect.cpp \
     $$PWD/qv4regexpobject.cpp \
     $$PWD/qv4stackframe.cpp \
+    $$PWD/qv4string.cpp \
     $$PWD/qv4stringiterator.cpp \
     $$PWD/qv4stringobject.cpp \
     $$PWD/qv4variantobject.cpp \
     $$PWD/qv4objectiterator.cpp \
     $$PWD/qv4regexp.cpp \
     $$PWD/qv4runtimecodegen.cpp \
-    $$PWD/qv4serialize.cpp \
     $$PWD/qv4script.cpp \
     $$PWD/qv4symbol.cpp \
     $$PWD/qv4setobject.cpp \
@@ -103,13 +104,13 @@ HEADERS += \
     $$PWD/qv4regexpobject_p.h \
     $$PWD/qv4runtimecodegen_p.h \
     $$PWD/qv4stackframe_p.h \
+    $$PWD/qv4string_p.h \
     $$PWD/qv4stringiterator_p.h \
     $$PWD/qv4stringobject_p.h \
     $$PWD/qv4variantobject_p.h \
     $$PWD/qv4property_p.h \
     $$PWD/qv4objectiterator_p.h \
     $$PWD/qv4regexp_p.h \
-    $$PWD/qv4serialize_p.h \
     $$PWD/qv4script_p.h \
     $$PWD/qv4symbol_p.h \
     $$PWD/qv4setobject_p.h \
@@ -142,18 +143,17 @@ qtConfig(qml-sequence-object) {
 
 
 HEADERS += \
+    $$PWD/qv4calldata_p.h \
     $$PWD/qv4runtime_p.h \
     $$PWD/qv4runtimeapi_p.h \
     $$PWD/qv4value_p.h \
-    $$PWD/qv4string_p.h \
+    $$PWD/qv4stringtoarrayindex_p.h \
     $$PWD/qv4util_p.h \
     $$PWD/qv4value_p.h \
     $$PWD/qv4functiontable_p.h
 
 SOURCES += \
-    $$PWD/qv4engine.cpp \
     $$PWD/qv4runtime.cpp \
-    $$PWD/qv4string.cpp \
     $$PWD/qv4value.cpp \
     $$PWD/qv4executableallocator.cpp
 
diff --git a/src/qml/jsruntime/qv4calldata_p.h b/src/qml/jsruntime/qv4calldata_p.h
new file mode 100644
index 0000000000..8487872bf5
--- /dev/null
+++ b/src/qml/jsruntime/qv4calldata_p.h
@@ -0,0 +1,113 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtQml module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QV4CALLDATA_P_H
+#define QV4CALLDATA_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <private/qv4value_p.h>
+
+QT_BEGIN_NAMESPACE
+
+namespace QV4 {
+
+struct CallData
+{
+    enum Offsets {
+        Function = 0,
+        Context = 1,
+        Accumulator = 2,
+        This = 3,
+        NewTarget = 4,
+        Argc = 5,
+
+        LastOffset = Argc,
+        OffsetCount = LastOffset + 1
+    };
+
+    Value function;
+    Value context;
+    Value accumulator;
+    Value thisObject;
+    Value newTarget;
+    Value _argc;
+
+    int argc() const {
+        Q_ASSERT(_argc.isInteger());
+        return _argc.int_32();
+    }
+
+    void setArgc(int argc) {
+        Q_ASSERT(argc >= 0);
+        _argc.setInt_32(argc);
+    }
+
+    inline ReturnedValue argument(int i) const {
+        return i < argc() ? args[i].asReturnedValue() : Value::undefinedValue().asReturnedValue();
+    }
+
+    Value args[1];
+
+    static Q_DECL_CONSTEXPR int HeaderSize() { return offsetof(CallData, args) / sizeof(QV4::Value); }
+};
+
+Q_STATIC_ASSERT(std::is_standard_layout<CallData>::value);
+Q_STATIC_ASSERT(offsetof(CallData, function   ) == CallData::Function    * sizeof(Value));
+Q_STATIC_ASSERT(offsetof(CallData, context    ) == CallData::Context     * sizeof(Value));
+Q_STATIC_ASSERT(offsetof(CallData, accumulator) == CallData::Accumulator * sizeof(Value));
+Q_STATIC_ASSERT(offsetof(CallData, thisObject ) == CallData::This        * sizeof(Value));
+Q_STATIC_ASSERT(offsetof(CallData, newTarget  ) == CallData::NewTarget   * sizeof(Value));
+Q_STATIC_ASSERT(offsetof(CallData, _argc      ) == CallData::Argc        * sizeof(Value));
+Q_STATIC_ASSERT(offsetof(CallData, args       ) == 6 * sizeof(Value));
+
+} // namespace QV4
+
+QT_END_NAMESPACE
+
+#endif // QV4CALLDATA_P_H
diff --git a/src/qml/jsruntime/qv4context.cpp b/src/qml/jsruntime/qv4context.cpp
index b3bcfe21d5..130727378d 100644
--- a/src/qml/jsruntime/qv4context.cpp
+++ b/src/qml/jsruntime/qv4context.cpp
@@ -60,7 +60,7 @@ Heap::CallContext *ExecutionContext::newBlockContext(CppStackFrame *frame, int b
 {
     Function *function = frame->v4Function;
 
-    Heap::InternalClass *ic = function->compilationUnit->runtimeBlocks.at(blockIndex);
+    Heap::InternalClass *ic = function->executableCompilationUnit()->runtimeBlocks.at(blockIndex);
     uint nLocals = ic->size;
     size_t requiredMemory = sizeof(CallContext::Data) - sizeof(Value) + sizeof(Value) * nLocals;
 
@@ -76,7 +76,7 @@ Heap::CallContext *ExecutionContext::newBlockContext(CppStackFrame *frame, int b
     c->locals.size = nLocals;
     c->locals.alloc = nLocals;
 
-    c->setupLocalTemporalDeadZone(function->compilationUnit->unitData()->blockAt(blockIndex));
+    c->setupLocalTemporalDeadZone(function->executableCompilationUnit()->unitData()->blockAt(blockIndex));
 
     return c;
 }
diff --git a/src/qml/jsruntime/qv4engine.cpp b/src/qml/jsruntime/qv4engine.cpp
index e10bf3cf79..cd77ebd22a 100644
--- a/src/qml/jsruntime/qv4engine.cpp
+++ b/src/qml/jsruntime/qv4engine.cpp
@@ -38,9 +38,6 @@
 ****************************************************************************/
 #include <qv4engine_p.h>
 
-#include <private/qqmljslexer_p.h>
-#include <private/qqmljsparser_p.h>
-#include <private/qqmljsast_p.h>
 #include <private/qv4compileddata_p.h>
 #include <private/qv4compiler_p.h>
 #include <private/qv4compilercontext_p.h>
@@ -55,8 +52,6 @@
 #include <QRegularExpression>
 #endif
 
-#ifndef V4_BOOTSTRAP
-
 #include <qv4qmlcontext_p.h>
 #include <qv4value_p.h>
 #include <qv4object_p.h>
@@ -107,7 +102,6 @@
 #include "qv4dataview_p.h"
 #include "qv4promiseobject_p.h"
 #include "qv4typedarray_p.h"
-#include <private/qv8engine_p.h>
 #include <private/qjsvalue_p.h>
 #include <private/qqmltypewrapper_p.h>
 #include <private/qqmlvaluetypewrapper_p.h>
@@ -115,9 +109,16 @@
 #include <private/qqmllistwrapper_p.h>
 #include <private/qqmllist_p.h>
 #include <private/qqmltypeloader_p.h>
+#include <private/qqmlmemoryprofiler_p.h>
+#include <private/qqmlbuiltinfunctions_p.h>
 #if QT_CONFIG(qml_locale)
 #include <private/qqmllocale_p.h>
 #endif
+#if QT_CONFIG(qml_xml_http_request)
+#include <private/qv4domerrors_p.h>
+#include <private/qqmlxmlhttprequest_p.h>
+#endif
+#include <private/qv4sqlerrors_p.h>
 #include <qqmlfile.h>
 
 #if USE(PTHREADS)
@@ -134,14 +135,12 @@
 #include <valgrind/memcheck.h>
 #endif
 
-#endif // #ifndef V4_BOOTSTRAP
+Q_DECLARE_METATYPE(QList<int>)
 
 QT_BEGIN_NAMESPACE
 
 using namespace QV4;
 
-#ifndef V4_BOOTSTRAP
-
 static QBasicAtomicInt engineSerial = Q_BASIC_ATOMIC_INITIALIZER(1);
 
 ReturnedValue throwTypeError(const FunctionObject *b, const QV4::Value *, const QV4::Value *, int)
@@ -151,6 +150,43 @@ ReturnedValue throwTypeError(const FunctionObject *b, const QV4::Value *, const
 
 qint32 ExecutionEngine::maxCallDepth = -1;
 
+template <typename ReturnType>
+ReturnType convertJSValueToVariantType(const QJSValue &value)
+{
+    return value.toVariant().value<ReturnType>();
+}
+
+static void saveJSValue(QDataStream &stream, const void *data)
+{
+    const QJSValue *jsv = reinterpret_cast<const QJSValue *>(data);
+    quint32 isNullOrUndefined = 0;
+    if (jsv->isNull())
+        isNullOrUndefined |= 0x1;
+    if (jsv->isUndefined())
+        isNullOrUndefined |= 0x2;
+    stream << isNullOrUndefined;
+    if (!isNullOrUndefined)
+        reinterpret_cast<const QJSValue*>(data)->toVariant().save(stream);
+}
+
+static void restoreJSValue(QDataStream &stream, void *data)
+{
+    QJSValue *jsv = reinterpret_cast<QJSValue*>(data);
+
+    quint32 isNullOrUndefined;
+    stream >> isNullOrUndefined;
+
+    if (isNullOrUndefined & 0x1) {
+        *jsv = QJSValue(QJSValue::NullValue);
+    } else if (isNullOrUndefined & 0x2) {
+        *jsv = QJSValue();
+    } else {
+        QVariant v;
+        v.load(stream);
+        QJSValuePrivate::setVariant(jsv, v);
+    }
+}
+
 ExecutionEngine::ExecutionEngine(QJSEngine *jsEngine)
     : executableAllocator(new QV4::ExecutableAllocator)
     , regExpAllocator(new QV4::ExecutableAllocator)
@@ -158,7 +194,6 @@ ExecutionEngine::ExecutionEngine(QJSEngine *jsEngine)
     , jsStack(new WTF::PageAllocation)
     , gcStack(new WTF::PageAllocation)
     , globalCode(nullptr)
-    , v8Engine(nullptr)
     , publicEngine(jsEngine)
     , m_engineId(engineSerial.fetchAndAddOrdered(1))
     , regExpCache(nullptr)
@@ -166,6 +201,10 @@ ExecutionEngine::ExecutionEngine(QJSEngine *jsEngine)
 #if QT_CONFIG(qml_jit)
     , m_canAllocateExecutableMemory(OSAllocator::canAllocateExecutableMemory())
 #endif
+#if QT_CONFIG(qml_xml_http_request)
+    , m_xmlHttpRequestData(nullptr)
+#endif
+    , m_qmlEngine(nullptr)
 {
     memoryManager = new QV4::MemoryManager(this);
 
@@ -652,11 +691,28 @@ ExecutionEngine::ExecutionEngine(QJSEngine *jsEngine)
     pd->set = thrower();
     functionPrototype()->insertMember(id_caller(), pd, Attr_Accessor|Attr_ReadOnly_ButConfigurable);
     functionPrototype()->insertMember(id_arguments(), pd, Attr_Accessor|Attr_ReadOnly_ButConfigurable);
+
+    QML_MEMORY_SCOPE_STRING("QV4Engine::QV4Engine");
+    qMetaTypeId<QJSValue>();
+    qMetaTypeId<QList<int> >();
+
+    if (!QMetaType::hasRegisteredConverterFunction<QJSValue, QVariantMap>())
+        QMetaType::registerConverter<QJSValue, QVariantMap>(convertJSValueToVariantType<QVariantMap>);
+    if (!QMetaType::hasRegisteredConverterFunction<QJSValue, QVariantList>())
+        QMetaType::registerConverter<QJSValue, QVariantList>(convertJSValueToVariantType<QVariantList>);
+    if (!QMetaType::hasRegisteredConverterFunction<QJSValue, QStringList>())
+        QMetaType::registerConverter<QJSValue, QStringList>(convertJSValueToVariantType<QStringList>);
+    QMetaType::registerStreamOperators(qMetaTypeId<QJSValue>(), saveJSValue, restoreJSValue);
+
+    QV4::QObjectWrapper::initializeBindings(this);
+
+    m_delayedCallQueue.init(this);
 }
 
 ExecutionEngine::~ExecutionEngine()
 {
     modules.clear();
+    qDeleteAll(m_extensionData);
     delete m_multiplyWrappedQObjects;
     m_multiplyWrappedQObjects = nullptr;
     delete identifierTable;
@@ -673,6 +729,11 @@ ExecutionEngine::~ExecutionEngine()
     delete jsStack;
     gcStack->deallocate();
     delete gcStack;
+
+#if QT_CONFIG(qml_xml_http_request)
+    qt_rem_qmlxmlhttprequest(this, m_xmlHttpRequestData);
+    m_xmlHttpRequestData = nullptr;
+#endif
 }
 
 ExecutionContext *ExecutionEngine::currentContext() const
@@ -1682,7 +1743,7 @@ ReturnedValue ExecutionEngine::global()
     return globalObject->asReturnedValue();
 }
 
-QQmlRefPointer<CompiledData::CompilationUnit> ExecutionEngine::compileModule(const QUrl &url)
+QQmlRefPointer<ExecutableCompilationUnit> ExecutionEngine::compileModule(const QUrl &url)
 {
     QFile f(QQmlFile::urlToLocalFileOrQrc(url));
     if (!f.open(QIODevice::ReadOnly)) {
@@ -1699,10 +1760,12 @@ QQmlRefPointer<CompiledData::CompilationUnit> ExecutionEngine::compileModule(con
 }
 
 
-QQmlRefPointer<CompiledData::CompilationUnit> ExecutionEngine::compileModule(const QUrl &url, const QString &sourceCode, const QDateTime &sourceTimeStamp)
+QQmlRefPointer<ExecutableCompilationUnit> ExecutionEngine::compileModule(
+        const QUrl &url, const QString &sourceCode, const QDateTime &sourceTimeStamp)
 {
     QList<QQmlJS::DiagnosticMessage> diagnostics;
-    auto unit = compileModule(/*debugMode*/debugger() != nullptr, url.toString(), sourceCode, sourceTimeStamp, &diagnostics);
+    auto unit = Compiler::Codegen::compileModule(/*debugMode*/debugger() != nullptr, url.toString(),
+                                                 sourceCode, sourceTimeStamp, &diagnostics);
     for (const QQmlJS::DiagnosticMessage &m : diagnostics) {
         if (m.isError()) {
             throwSyntaxError(m.message, url.toString(), m.loc.startLine, m.loc.startColumn);
@@ -1712,56 +1775,11 @@ QQmlRefPointer<CompiledData::CompilationUnit> ExecutionEngine::compileModule(con
                       << ": warning: " << m.message;
         }
     }
-    return unit;
-}
-
-#endif // ifndef V4_BOOTSTRAP
-
-QQmlRefPointer<CompiledData::CompilationUnit> ExecutionEngine::compileModule(bool debugMode, const QString &url, const QString &sourceCode,
-                                                                             const QDateTime &sourceTimeStamp, QList<QQmlJS::DiagnosticMessage> *diagnostics)
-{
-    QQmlJS::Engine ee;
-    QQmlJS::Lexer lexer(&ee);
-    lexer.setCode(sourceCode, /*line*/1, /*qml mode*/false);
-    QQmlJS::Parser parser(&ee);
-
-    const bool parsed = parser.parseModule();
-
-    if (diagnostics)
-        *diagnostics = parser.diagnosticMessages();
-
-    if (!parsed)
-        return nullptr;
-
-    QQmlJS::AST::ESModule *moduleNode = QQmlJS::AST::cast<QQmlJS::AST::ESModule*>(parser.rootNode());
-    if (!moduleNode) {
-        // if parsing was successful, and we have no module, then
-        // the file was empty.
-        if (diagnostics)
-            diagnostics->clear();
-        return nullptr;
-    }
-
-    using namespace QV4::Compiler;
-    Compiler::Module compilerModule(debugMode);
-    compilerModule.unitFlags |= CompiledData::Unit::IsESModule;
-    compilerModule.sourceTimeStamp = sourceTimeStamp;
-    JSUnitGenerator jsGenerator(&compilerModule);
-    Codegen cg(&jsGenerator, /*strictMode*/true);
-    cg.generateFromModule(url, url, sourceCode, moduleNode, &compilerModule);
-    auto errors = cg.errors();
-    if (diagnostics)
-        *diagnostics << errors;
-
-    if (!errors.isEmpty())
-        return nullptr;
 
-    return cg.generateCompilationUnit();
+    return ExecutableCompilationUnit::create(std::move(unit));
 }
 
-#ifndef V4_BOOTSTRAP
-
-void ExecutionEngine::injectModule(const QQmlRefPointer<CompiledData::CompilationUnit> &moduleUnit)
+void ExecutionEngine::injectModule(const QQmlRefPointer<ExecutableCompilationUnit> &moduleUnit)
 {
     // Injection can happen from the QML type loader thread for example, but instantiation and
     // evaluation must be limited to the ExecutionEngine's thread.
@@ -1769,7 +1787,7 @@ void ExecutionEngine::injectModule(const QQmlRefPointer<CompiledData::Compilatio
     modules.insert(moduleUnit->finalUrl(), moduleUnit);
 }
 
-QQmlRefPointer<CompiledData::CompilationUnit> ExecutionEngine::moduleForUrl(const QUrl &_url, const CompiledData::CompilationUnit *referrer) const
+QQmlRefPointer<ExecutableCompilationUnit> ExecutionEngine::moduleForUrl(const QUrl &_url, const ExecutableCompilationUnit *referrer) const
 {
     QUrl url = QQmlTypeLoader::normalize(_url);
     if (referrer)
@@ -1782,7 +1800,7 @@ QQmlRefPointer<CompiledData::CompilationUnit> ExecutionEngine::moduleForUrl(cons
     return *existingModule;
 }
 
-QQmlRefPointer<CompiledData::CompilationUnit> ExecutionEngine::loadModule(const QUrl &_url, const CompiledData::CompilationUnit *referrer)
+QQmlRefPointer<ExecutableCompilationUnit> ExecutionEngine::loadModule(const QUrl &_url, const ExecutableCompilationUnit *referrer)
 {
     QUrl url = QQmlTypeLoader::normalize(_url);
     if (referrer)
@@ -1804,6 +1822,133 @@ QQmlRefPointer<CompiledData::CompilationUnit> ExecutionEngine::loadModule(const
     return newModule;
 }
 
+void ExecutionEngine::initQmlGlobalObject()
+{
+    initializeGlobal();
+    freezeObject(*globalObject);
+}
+
+void ExecutionEngine::initializeGlobal()
+{
+    QV4::Scope scope(this);
+    QV4::GlobalExtensions::init(globalObject, QJSEngine::AllExtensions);
+
+    QV4::ScopedObject qt(scope, memoryManager->allocate<QV4::QtObject>(qmlEngine()));
+    globalObject->defineDefaultProperty(QStringLiteral("Qt"), qt);
+
+#if QT_CONFIG(qml_locale)
+    QQmlLocale::registerStringLocaleCompare(this);
+    QQmlDateExtension::registerExtension(this);
+    QQmlNumberExtension::registerExtension(this);
+#endif
+
+#if QT_CONFIG(qml_xml_http_request)
+    qt_add_domexceptions(this);
+    m_xmlHttpRequestData = qt_add_qmlxmlhttprequest(this);
+#endif
+
+    qt_add_sqlexceptions(this);
+
+    {
+        for (uint i = 0; i < globalObject->internalClass()->size; ++i) {
+            if (globalObject->internalClass()->nameMap.at(i).isString()) {
+                QV4::PropertyKey id = globalObject->internalClass()->nameMap.at(i);
+                m_illegalNames.insert(id.toQString());
+            }
+        }
+    }
+}
+
+const QSet<QString> &ExecutionEngine::illegalNames() const
+{
+    return m_illegalNames;
+}
+
+void ExecutionEngine::setQmlEngine(QQmlEngine *engine)
+{
+    m_qmlEngine = engine;
+    initQmlGlobalObject();
+}
+
+static void freeze_recursive(QV4::ExecutionEngine *v4, QV4::Object *object)
+{
+    if (object->as<QV4::QObjectWrapper>())
+        return;
+
+    QV4::Scope scope(v4);
+
+    bool instanceOfObject = false;
+    QV4::ScopedObject p(scope, object->getPrototypeOf());
+    while (p) {
+        if (p->d() == v4->objectPrototype()->d()) {
+            instanceOfObject = true;
+            break;
+        }
+        p = p->getPrototypeOf();
+    }
+    if (!instanceOfObject)
+        return;
+
+    QV4::Heap::InternalClass *frozen = object->internalClass()->propertiesFrozen();
+    if (object->internalClass() == frozen)
+        return;
+    object->setInternalClass(frozen);
+
+    QV4::ScopedObject o(scope);
+    for (uint i = 0; i < frozen->size; ++i) {
+        if (!frozen->nameMap.at(i).isStringOrSymbol())
+            continue;
+        o = *object->propertyData(i);
+        if (o)
+            freeze_recursive(v4, o);
+    }
+}
+
+void ExecutionEngine::freezeObject(const QV4::Value &value)
+{
+    QV4::Scope scope(this);
+    QV4::ScopedObject o(scope, value);
+    freeze_recursive(this, o);
+}
+
+void ExecutionEngine::startTimer(const QString &timerName)
+{
+    if (!m_time.isValid())
+        m_time.start();
+    m_startedTimers[timerName] = m_time.elapsed();
+}
+
+qint64 ExecutionEngine::stopTimer(const QString &timerName, bool *wasRunning)
+{
+    if (!m_startedTimers.contains(timerName)) {
+        *wasRunning = false;
+        return 0;
+    }
+    *wasRunning = true;
+    qint64 startedAt = m_startedTimers.take(timerName);
+    return m_time.elapsed() - startedAt;
+}
+
+int ExecutionEngine::consoleCountHelper(const QString &file, quint16 line, quint16 column)
+{
+    const QString key = file + QString::number(line) + QString::number(column);
+    int number = m_consoleCount.value(key, 0);
+    number++;
+    m_consoleCount.insert(key, number);
+    return number;
+}
+
+void ExecutionEngine::setExtensionData(int index, Deletable *data)
+{
+    if (m_extensionData.count() <= index)
+        m_extensionData.resize(index + 1);
+
+    if (m_extensionData.at(index))
+        delete m_extensionData.at(index);
+
+    m_extensionData[index] = data;
+}
+
 // Converts a JS value to a meta-type.
 // data must point to a place that can store a value of the given type.
 // Returns true if conversion succeeded, false otherwise.
@@ -2050,6 +2195,23 @@ static QObject *qtObjectFromJS(QV4::ExecutionEngine *engine, const QV4::Value &v
     return wrapper->object();
 }
 
-#endif // ifndef V4_BOOTSTRAP
+struct QV4EngineRegistrationData
+{
+    QV4EngineRegistrationData() : extensionCount(0) {}
+
+    QMutex mutex;
+    int extensionCount;
+};
+Q_GLOBAL_STATIC(QV4EngineRegistrationData, registrationData);
+
+QMutex *ExecutionEngine::registrationMutex()
+{
+    return &registrationData()->mutex;
+}
+
+int ExecutionEngine::registerExtension()
+{
+    return registrationData()->extensionCount++;
+}
 
 QT_END_NAMESPACE
diff --git a/src/qml/jsruntime/qv4engine_p.h b/src/qml/jsruntime/qv4engine_p.h
index d0c58eee8f..f8ac0e0268 100644
--- a/src/qml/jsruntime/qv4engine_p.h
+++ b/src/qml/jsruntime/qv4engine_p.h
@@ -53,25 +53,83 @@
 #include "qv4global_p.h"
 #include "qv4managed_p.h"
 #include "qv4context_p.h"
+#include "qv4stackframe_p.h"
 #include <private/qintrusivelist_p.h>
 #include "qv4enginebase_p.h"
 #include <private/qqmlrefcount_p.h>
 #include <private/qqmljsengine_p.h>
+#include <private/qqmldelayedcallqueue_p.h>
+#include <QtCore/qelapsedtimer.h>
+#include <QtCore/qmutex.h>
 
-#ifndef V4_BOOTSTRAP
-#  include "qv4function_p.h"
-#  include <private/qv8engine_p.h>
-#  include <private/qv4compileddata_p.h>
-#endif
+#include "qv4function_p.h"
+#include <private/qv4compileddata_p.h>
+#include <private/qv4executablecompilationunit_p.h>
 
 namespace WTF {
 class BumpPointerAllocator;
 class PageAllocation;
 }
 
+#define V4_DEFINE_EXTENSION(dataclass, datafunction) \
+    static inline dataclass *datafunction(QV4::ExecutionEngine *engine) \
+    { \
+        static int extensionId = -1; \
+        if (extensionId == -1) { \
+            QV4::ExecutionEngine::registrationMutex()->lock(); \
+            if (extensionId == -1) \
+                extensionId = QV4::ExecutionEngine::registerExtension(); \
+            QV4::ExecutionEngine::registrationMutex()->unlock(); \
+        } \
+        dataclass *rv = (dataclass *)engine->extensionData(extensionId); \
+        if (!rv) { \
+            rv = new dataclass(engine); \
+            engine->setExtensionData(extensionId, rv); \
+        } \
+        return rv; \
+    } \
+
+
 QT_BEGIN_NAMESPACE
 
-class QV8Engine;
+namespace QV4 { struct QObjectMethod; }
+
+// Used to allow a QObject method take and return raw V4 handles without having to expose
+// 48 in the public API.
+// Use like this:
+//     class MyClass : public QObject {
+//         Q_OBJECT
+//         ...
+//         Q_INVOKABLE void myMethod(QQmlV4Function*);
+//     };
+// The QQmlV8Function - and consequently the arguments and return value - only remains
+// valid during the call.  If the return value isn't set within myMethod(), the will return
+// undefined.
+
+class QQmlV4Function
+{
+public:
+    int length() const { return callData->argc(); }
+    QV4::ReturnedValue operator[](int idx) const { return (idx < callData->argc() ? callData->args[idx].asReturnedValue() : QV4::Encode::undefined()); }
+    void setReturnValue(QV4::ReturnedValue rv) { *retVal = rv; }
+    QV4::ExecutionEngine *v4engine() const { return e; }
+private:
+    friend struct QV4::QObjectMethod;
+    QQmlV4Function();
+    QQmlV4Function(const QQmlV4Function &);
+    QQmlV4Function &operator=(const QQmlV4Function &);
+
+    QQmlV4Function(QV4::CallData *callData, QV4::Value *retVal, QV4::ExecutionEngine *e)
+        : callData(callData), retVal(retVal), e(e)
+    {
+        callData->thisObject = QV4::Encode::undefined();
+    }
+
+    QV4::CallData *callData;
+    QV4::Value *retVal;
+    QV4::ExecutionEngine *e;
+};
+
 class QQmlError;
 class QJSEngine;
 class QQmlEngine;
@@ -128,14 +186,8 @@ public:
 
     Function *globalCode;
 
-#ifdef V4_BOOTSTRAP
-    QJSEngine *jsEngine() const;
-    QQmlEngine *qmlEngine() const;
-#else // !V4_BOOTSTRAP
     QJSEngine *jsEngine() const { return publicEngine; }
-    QQmlEngine *qmlEngine() const { return v8Engine ? v8Engine->engine() : nullptr; }
-#endif // V4_BOOTSTRAP
-    QV8Engine *v8Engine;
+    QQmlEngine *qmlEngine() const { return m_qmlEngine; }
     QJSEngine *publicEngine;
 
     enum JSObjects {
@@ -438,9 +490,7 @@ public:
     Symbol *symbol_unscopables() const { return reinterpret_cast<Symbol *>(jsSymbols + Symbol_unscopables); }
     Symbol *symbol_revokableProxy() const { return reinterpret_cast<Symbol *>(jsSymbols + Symbol_revokableProxy); }
 
-#ifndef V4_BOOTSTRAP
-    QIntrusiveList<CompiledData::CompilationUnit, &CompiledData::CompilationUnit::nextCompilationUnit> compilationUnits;
-#endif
+    QIntrusiveList<ExecutableCompilationUnit, &ExecutableCompilationUnit::nextCompilationUnit> compilationUnits;
 
     quint32 m_engineId;
 
@@ -608,30 +658,82 @@ public:
     }
 
     QV4::ReturnedValue global();
+    void initQmlGlobalObject();
+    void initializeGlobal();
+
+    void freezeObject(const QV4::Value &value);
+
+    // Return the list of illegal id names (the names of the properties on the global object)
+    const QSet<QString> &illegalNames() const;
+
+#if QT_CONFIG(qml_xml_http_request)
+    void *xmlHttpRequestData() const { return m_xmlHttpRequestData; }
+#endif
+
+    void setQmlEngine(QQmlEngine *engine);
+
+    QQmlDelayedCallQueue *delayedCallQueue() { return &m_delayedCallQueue; }
+
+    // used for console.time(), console.timeEnd()
+    void startTimer(const QString &timerName);
+    qint64 stopTimer(const QString &timerName, bool *wasRunning);
+
+    // used for console.count()
+    int consoleCountHelper(const QString &file, quint16 line, quint16 column);
+
+    struct Deletable {
+        virtual ~Deletable() {}
+    };
+
+    static QMutex *registrationMutex();
+    static int registerExtension();
+
+    void setExtensionData(int, Deletable *);
+    Deletable *extensionData(int index) const
+    {
+        if (index < m_extensionData.count())
+            return m_extensionData[index];
+        else
+            return nullptr;
+    }
 
     double localTZA = 0.0; // local timezone, initialized at startup
 
-    static QQmlRefPointer<CompiledData::CompilationUnit> compileModule(bool debugMode, const QString &url, const QString &sourceCode, const QDateTime &sourceTimeStamp, QList<QQmlJS::DiagnosticMessage> *diagnostics);
-#ifndef V4_BOOTSTRAP
-    QQmlRefPointer<CompiledData::CompilationUnit> compileModule(const QUrl &url);
-    QQmlRefPointer<CompiledData::CompilationUnit> compileModule(const QUrl &url, const QString &sourceCode, const QDateTime &sourceTimeStamp);
+    QQmlRefPointer<ExecutableCompilationUnit> compileModule(const QUrl &url);
+    QQmlRefPointer<ExecutableCompilationUnit> compileModule(
+            const QUrl &url, const QString &sourceCode, const QDateTime &sourceTimeStamp);
 
     mutable QMutex moduleMutex;
-    QHash<QUrl, QQmlRefPointer<CompiledData::CompilationUnit>> modules;
-    void injectModule(const QQmlRefPointer<CompiledData::CompilationUnit> &moduleUnit);
-    QQmlRefPointer<CompiledData::CompilationUnit> moduleForUrl(const QUrl &_url, const CompiledData::CompilationUnit *referrer = nullptr) const;
-    QQmlRefPointer<CompiledData::CompilationUnit> loadModule(const QUrl &_url, const CompiledData::CompilationUnit *referrer = nullptr);
-#endif
+    QHash<QUrl, QQmlRefPointer<ExecutableCompilationUnit>> modules;
+    void injectModule(const QQmlRefPointer<ExecutableCompilationUnit> &moduleUnit);
+    QQmlRefPointer<ExecutableCompilationUnit> moduleForUrl(const QUrl &_url, const ExecutableCompilationUnit *referrer = nullptr) const;
+    QQmlRefPointer<ExecutableCompilationUnit> loadModule(const QUrl &_url, const ExecutableCompilationUnit *referrer = nullptr);
 
 private:
 #if QT_CONFIG(qml_debug)
     QScopedPointer<QV4::Debugging::Debugger> m_debugger;
     QScopedPointer<QV4::Profiling::Profiler> m_profiler;
 #endif
+    QSet<QString> m_illegalNames;
     int jitCallCountThreshold;
 
     // used by generated Promise objects to handle 'then' events
     QScopedPointer<QV4::Promise::ReactionHandler> m_reactionHandler;
+
+#if QT_CONFIG(qml_xml_http_request)
+    void *m_xmlHttpRequestData;
+#endif
+
+    QQmlEngine *m_qmlEngine;
+
+    QQmlDelayedCallQueue m_delayedCallQueue;
+
+    QElapsedTimer m_time;
+    QHash<QString, qint64> m_startedTimers;
+
+    QHash<QString, quint32> m_consoleCount;
+
+    QVector<Deletable *> m_extensionData;
 };
 
 #define CHECK_STACK_LIMITS(v4) if ((v4)->checkStackLimits()) return Encode::undefined(); \
diff --git a/src/qml/jsruntime/qv4enginebase_p.h b/src/qml/jsruntime/qv4enginebase_p.h
index 82eccd9f3c..788897bdad 100644
--- a/src/qml/jsruntime/qv4enginebase_p.h
+++ b/src/qml/jsruntime/qv4enginebase_p.h
@@ -79,9 +79,6 @@ struct Q_QML_EXPORT EngineBase {
 #elif defined(Q_ATOMIC_INT16_IS_SUPPORTED)
     quint8 unused = 0;
     QAtomicInteger<quint16> isInterrupted = false;
-#elif defined(V4_BOOTSTRAP)
-    // We don't need the isInterrupted flag when bootstrapping.
-    quint8 unused[3];
 #else
 #   error V4 needs either 8bit or 16bit atomics.
 #endif
@@ -150,10 +147,7 @@ Q_STATIC_ASSERT(offsetof(EngineBase, jsStackTop) == offsetof(EngineBase, current
 Q_STATIC_ASSERT(offsetof(EngineBase, hasException) == offsetof(EngineBase, jsStackTop) + QT_POINTER_SIZE);
 Q_STATIC_ASSERT(offsetof(EngineBase, memoryManager) == offsetof(EngineBase, hasException) + 8);
 Q_STATIC_ASSERT(offsetof(EngineBase, runtime) == offsetof(EngineBase, memoryManager) + QT_POINTER_SIZE);
-
-#ifndef V4_BOOTSTRAP
 Q_STATIC_ASSERT(offsetof(EngineBase, isInterrupted) + sizeof(EngineBase::isInterrupted) <= offsetof(EngineBase, hasException) + 4);
-#endif
 
 }
 
diff --git a/src/qml/jsruntime/qv4function.cpp b/src/qml/jsruntime/qv4function.cpp
index debdf23d27..d870cec68a 100644
--- a/src/qml/jsruntime/qv4function.cpp
+++ b/src/qml/jsruntime/qv4function.cpp
@@ -73,7 +73,8 @@ ReturnedValue Function::call(const Value *thisObject, const Value *argv, int arg
     return result;
 }
 
-Function *Function::create(ExecutionEngine *engine, CompiledData::CompilationUnit *unit, const CompiledData::Function *function)
+Function *Function::create(ExecutionEngine *engine, ExecutableCompilationUnit *unit,
+                           const CompiledData::Function *function)
 {
     return new Function(engine, unit, function);
 }
@@ -83,7 +84,8 @@ void Function::destroy()
     delete this;
 }
 
-Function::Function(ExecutionEngine *engine, CompiledData::CompilationUnit *unit, const CompiledData::Function *function)
+Function::Function(ExecutionEngine *engine, ExecutableCompilationUnit *unit,
+                   const CompiledData::Function *function)
     : FunctionData(unit)
     , compiledFunction(function)
     , codeData(function->code())
@@ -146,8 +148,11 @@ void Function::updateInternalClass(ExecutionEngine *engine, const QList<QByteArr
 
     // first locals
     const quint32_le *localsIndices = compiledFunction->localsTable();
-    for (quint32 i = 0; i < compiledFunction->nLocals; ++i)
-        internalClass = internalClass->addMember(engine->identifierTable->asPropertyKey(compilationUnit->runtimeStrings[localsIndices[i]]), Attr_NotConfigurable);
+    for (quint32 i = 0; i < compiledFunction->nLocals; ++i) {
+        internalClass = internalClass->addMember(
+                engine->identifierTable->asPropertyKey(compilationUnit->runtimeStrings[localsIndices[i]]),
+                Attr_NotConfigurable);
+    }
 
     Scope scope(engine);
     ScopedString arg(scope);
diff --git a/src/qml/jsruntime/qv4function_p.h b/src/qml/jsruntime/qv4function_p.h
index 01b212370d..cbbb61c68c 100644
--- a/src/qml/jsruntime/qv4function_p.h
+++ b/src/qml/jsruntime/qv4function_p.h
@@ -51,7 +51,7 @@
 //
 
 #include "qv4global_p.h"
-#include <private/qv4compileddata_p.h>
+#include <private/qv4executablecompilationunit_p.h>
 #include <private/qv4context_p.h>
 
 namespace JSC {
@@ -65,9 +65,13 @@ struct QQmlSourceLocation;
 namespace QV4 {
 
 struct Q_QML_EXPORT FunctionData {
-    CompiledData::CompilationUnit *compilationUnit;
+    CompiledData::CompilationUnitBase *compilationUnit;
 
-    FunctionData(CompiledData::CompilationUnit *compilationUnit)
+    // Intentionally require an ExecutableCompilationUnit but save only a pointer to
+    // CompilationUnitBase. This is so that we can take advantage of the standard layout
+    // of CompilationUnitBase in the JIT. Furthermore we can safely static_cast to
+    // ExecutableCompilationUnit where we need it.
+    FunctionData(ExecutableCompilationUnit *compilationUnit)
         : compilationUnit(compilationUnit)
     {}
 };
@@ -76,12 +80,24 @@ Q_STATIC_ASSERT(std::is_standard_layout< FunctionData >::value);
 
 struct Q_QML_EXPORT Function : public FunctionData {
 private:
-    Function(ExecutionEngine *engine, CompiledData::CompilationUnit *unit, const CompiledData::Function *function);
+    Function(ExecutionEngine *engine, ExecutableCompilationUnit *unit,
+             const CompiledData::Function *function);
     ~Function();
 
 public:
     const CompiledData::Function *compiledFunction;
 
+    QV4::ExecutableCompilationUnit *executableCompilationUnit() const
+    {
+        // This is safe: We require an ExecutableCompilationUnit in the ctor.
+        return static_cast<QV4::ExecutableCompilationUnit *>(compilationUnit);
+    }
+
+    QV4::Heap::String *runtimeString(uint i)
+    {
+        return compilationUnit->runtimeStrings[i];
+    }
+
     ReturnedValue call(const Value *thisObject, const Value *argv, int argc, const ExecutionContext *context);
 
     const char *codeData;
@@ -96,7 +112,8 @@ public:
     int interpreterCallCount = 0;
     bool isEval = false;
 
-    static Function *create(ExecutionEngine *engine, CompiledData::CompilationUnit *unit, const CompiledData::Function *function);
+    static Function *create(ExecutionEngine *engine, ExecutableCompilationUnit *unit,
+                            const CompiledData::Function *function);
     void destroy();
 
     // used when dynamically assigning signal handlers (QQmlConnection)
@@ -108,8 +125,8 @@ public:
 
     static QString prettyName(const Function *function, const void *address);
 
-    inline QString sourceFile() const { return compilationUnit->fileName(); }
-    inline QUrl finalUrl() const { return compilationUnit->finalUrl(); }
+    inline QString sourceFile() const { return executableCompilationUnit()->fileName(); }
+    inline QUrl finalUrl() const { return executableCompilationUnit()->finalUrl(); }
 
     inline bool isStrict() const { return compiledFunction->flags & CompiledData::Function::IsStrict; }
     inline bool isArrowFunction() const { return compiledFunction->flags & CompiledData::Function::IsArrowFunction; }
@@ -121,7 +138,7 @@ public:
     {
         if (compiledFunction->nestedFunctionIndex == std::numeric_limits<uint32_t>::max())
             return nullptr;
-        return compilationUnit->runtimeFunctions[compiledFunction->nestedFunctionIndex];
+        return executableCompilationUnit()->runtimeFunctions[compiledFunction->nestedFunctionIndex];
     }
 };
 
diff --git a/src/qml/jsruntime/qv4functionobject.cpp b/src/qml/jsruntime/qv4functionobject.cpp
index 41a21ba379..b1b0d67e64 100644
--- a/src/qml/jsruntime/qv4functionobject.cpp
+++ b/src/qml/jsruntime/qv4functionobject.cpp
@@ -135,13 +135,13 @@ void Heap::FunctionObject::setFunction(Function *f)
 {
     if (f) {
         function = f;
-        function->compilationUnit->addref();
+        function->executableCompilationUnit()->addref();
     }
 }
 void Heap::FunctionObject::destroy()
 {
     if (function)
-        function->compilationUnit->release();
+        function->executableCompilationUnit()->release();
     Object::destroy();
 }
 
@@ -229,7 +229,7 @@ void Heap::FunctionCtor::init(QV4::ExecutionContext *scope)
 }
 
 // 15.3.2
-QQmlRefPointer<CompiledData::CompilationUnit> FunctionCtor::parse(ExecutionEngine *engine, const Value *argv, int argc, Type t)
+QQmlRefPointer<ExecutableCompilationUnit> FunctionCtor::parse(ExecutionEngine *engine, const Value *argv, int argc, Type t)
 {
     QString arguments;
     QString body;
@@ -273,14 +273,15 @@ QQmlRefPointer<CompiledData::CompilationUnit> FunctionCtor::parse(ExecutionEngin
     if (engine->hasException)
         return nullptr;
 
-    return cg.generateCompilationUnit();
+    return ExecutableCompilationUnit::create(cg.generateCompilationUnit());
 }
 
 ReturnedValue FunctionCtor::virtualCallAsConstructor(const FunctionObject *f, const Value *argv, int argc, const Value *newTarget)
 {
     ExecutionEngine *engine = f->engine();
 
-    QQmlRefPointer<CompiledData::CompilationUnit> compilationUnit = parse(engine, argv, argc, Type_Function);
+    QQmlRefPointer<ExecutableCompilationUnit> compilationUnit
+            = parse(engine, argv, argc, Type_Function);
     if (engine->hasException)
         return Encode::undefined();
 
diff --git a/src/qml/jsruntime/qv4functionobject_p.h b/src/qml/jsruntime/qv4functionobject_p.h
index 4fee26f341..c99cad8e33 100644
--- a/src/qml/jsruntime/qv4functionobject_p.h
+++ b/src/qml/jsruntime/qv4functionobject_p.h
@@ -244,7 +244,7 @@ protected:
         Type_Function,
         Type_Generator
     };
-    static QQmlRefPointer<CompiledData::CompilationUnit> parse(ExecutionEngine *engine, const Value *argv, int argc, Type t = Type_Function);
+    static QQmlRefPointer<ExecutableCompilationUnit> parse(ExecutionEngine *engine, const Value *argv, int argc, Type t = Type_Function);
 };
 
 struct FunctionPrototype: FunctionObject
diff --git a/src/qml/jsruntime/qv4generatorobject.cpp b/src/qml/jsruntime/qv4generatorobject.cpp
index 14caa6953f..4eee6f4338 100644
--- a/src/qml/jsruntime/qv4generatorobject.cpp
+++ b/src/qml/jsruntime/qv4generatorobject.cpp
@@ -58,7 +58,7 @@ ReturnedValue GeneratorFunctionCtor::virtualCallAsConstructor(const FunctionObje
 {
     ExecutionEngine *engine = f->engine();
 
-    QQmlRefPointer<CompiledData::CompilationUnit> compilationUnit = parse(engine, argv, argc, Type_Generator);
+    QQmlRefPointer<ExecutableCompilationUnit> compilationUnit = parse(engine, argv, argc, Type_Generator);
     if (engine->hasException)
         return Encode::undefined();
 
diff --git a/src/qml/jsruntime/qv4include.cpp b/src/qml/jsruntime/qv4include.cpp
index 3c732bc555..c0885a418c 100644
--- a/src/qml/jsruntime/qv4include.cpp
+++ b/src/qml/jsruntime/qv4include.cpp
@@ -72,13 +72,17 @@ QV4Include::QV4Include(const QUrl &url, QV4::ExecutionEngine *engine,
     m_resultObject.set(v4, resultValue(v4));
 
 #if QT_CONFIG(qml_network)
-    m_network = engine->v8Engine->networkAccessManager();
+    if (QQmlEngine *qmlEngine = engine->qmlEngine()) {
+        m_network = qmlEngine->networkAccessManager();
 
-    QNetworkRequest request;
-    request.setUrl(url);
+        QNetworkRequest request;
+        request.setUrl(url);
 
-    m_reply = m_network->get(request);
-    QObject::connect(m_reply, SIGNAL(finished()), this, SLOT(finished()));
+        m_reply = m_network->get(request);
+        QObject::connect(m_reply, SIGNAL(finished()), this, SLOT(finished()));
+    } else {
+        finished();
+    }
 #else
     finished();
 #endif
@@ -197,7 +201,7 @@ void QV4Include::finished()
 }
 
 /*
-    Documented in qv8engine.cpp
+    Documented in qv4engine.cpp
 */
 QV4::ReturnedValue QV4Include::method_include(const QV4::FunctionObject *b, const QV4::Value *, const QV4::Value *argv, int argc)
 {
diff --git a/src/qml/jsruntime/qv4lookup_p.h b/src/qml/jsruntime/qv4lookup_p.h
index f2e0afd797..94bf1a98ae 100644
--- a/src/qml/jsruntime/qv4lookup_p.h
+++ b/src/qml/jsruntime/qv4lookup_p.h
@@ -54,11 +54,8 @@
 #include "qv4runtime_p.h"
 #include "qv4engine_p.h"
 #include "qv4context_p.h"
-
-#if !defined(V4_BOOTSTRAP)
 #include "qv4object_p.h"
 #include "qv4internalclass_p.h"
-#endif
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/qml/jsruntime/qv4managed_p.h b/src/qml/jsruntime/qv4managed_p.h
index d85b30a056..4f22dc7330 100644
--- a/src/qml/jsruntime/qv4managed_p.h
+++ b/src/qml/jsruntime/qv4managed_p.h
@@ -54,7 +54,6 @@
 #include "qv4value_p.h"
 #include "qv4enginebase_p.h"
 #include <private/qv4heap_p.h>
-#include <private/qv4writebarrier_p.h>
 #include <private/qv4vtable_p.h>
 
 QT_BEGIN_NAMESPACE
diff --git a/src/qml/jsruntime/qv4memberdata.cpp b/src/qml/jsruntime/qv4memberdata.cpp
index f327c85001..ffebe1b5da 100644
--- a/src/qml/jsruntime/qv4memberdata.cpp
+++ b/src/qml/jsruntime/qv4memberdata.cpp
@@ -72,8 +72,8 @@ Heap::MemberData *MemberData::allocate(ExecutionEngine *e, uint n, Heap::MemberD
 
     // The above code can overflow in a number of interesting ways. All of those are unsigned,
     // and therefore defined behavior. Still, apply some sane bounds.
-    if (alloc > std::numeric_limits<int>::max())
-        alloc = std::numeric_limits<int>::max();
+    if (alloc > size_t(std::numeric_limits<int>::max()))
+        alloc = size_t(std::numeric_limits<int>::max());
 
     Heap::MemberData *m;
     if (old) {
diff --git a/src/qml/jsruntime/qv4module.cpp b/src/qml/jsruntime/qv4module.cpp
index 237ada8321..08a1900383 100644
--- a/src/qml/jsruntime/qv4module.cpp
+++ b/src/qml/jsruntime/qv4module.cpp
@@ -52,7 +52,7 @@ using namespace QV4;
 
 DEFINE_OBJECT_VTABLE(Module);
 
-void Heap::Module::init(ExecutionEngine *engine, CompiledData::CompilationUnit *moduleUnit)
+void Heap::Module::init(ExecutionEngine *engine, ExecutableCompilationUnit *moduleUnit)
 {
     Object::init();
 
@@ -106,7 +106,7 @@ void Module::evaluate()
         return;
     d()->evaluated = true;
 
-    CompiledData::CompilationUnit *unit = d()->unit;
+    ExecutableCompilationUnit *unit = d()->unit;
 
     unit->evaluateModuleRequests();
 
diff --git a/src/qml/jsruntime/qv4module_p.h b/src/qml/jsruntime/qv4module_p.h
index dca0678fe9..aabb2e005e 100644
--- a/src/qml/jsruntime/qv4module_p.h
+++ b/src/qml/jsruntime/qv4module_p.h
@@ -60,7 +60,7 @@ namespace QV4 {
 namespace Heap {
 
 #define ModuleMembers(class, Member) \
-    Member(class, NoMark, CompiledData::CompilationUnit *, unit) \
+    Member(class, NoMark, ExecutableCompilationUnit *, unit) \
     Member(class, Pointer, CallContext *, scope) \
     Member(class, HeapValue, HeapValue, self) \
     Member(class, NoMark, bool, evaluated)
@@ -68,7 +68,7 @@ namespace Heap {
 DECLARE_EXPORTED_HEAP_OBJECT(Module, Object) {
     DECLARE_MARKOBJECTS(Module)
 
-    void init(ExecutionEngine *engine, CompiledData::CompilationUnit *moduleUnit);
+    void init(ExecutionEngine *engine, ExecutableCompilationUnit *moduleUnit);
 };
 
 }
diff --git a/src/qml/jsruntime/qv4object.cpp b/src/qml/jsruntime/qv4object.cpp
index 206b410cf4..89161433ed 100644
--- a/src/qml/jsruntime/qv4object.cpp
+++ b/src/qml/jsruntime/qv4object.cpp
@@ -93,7 +93,7 @@ void Heap::Object::setUsedAsProto()
     internalClass.set(internalClass->engine, internalClass->asProtoClass());
 }
 
-ReturnedValue Object::getValueAccessor(const Value &thisObject, const Value &v, PropertyAttributes attrs)
+ReturnedValue Object::getValueAccessor(const Value *thisObject, const Value &v, PropertyAttributes attrs)
 {
     if (!attrs.isAccessor())
         return v.asReturnedValue();
@@ -103,7 +103,8 @@ ReturnedValue Object::getValueAccessor(const Value &thisObject, const Value &v,
 
     Scope scope(f->engine());
     JSCallData jsCallData(scope);
-    *jsCallData->thisObject = thisObject;
+    if (thisObject)
+        *jsCallData->thisObject = *thisObject;
     return f->call(jsCallData);
 }
 
@@ -415,7 +416,7 @@ ReturnedValue Object::internalGet(PropertyKey id, const Value *receiver, bool *h
             if (o->arrayData && o->arrayData->getProperty(index, pd, &attrs)) {
                 if (hasProperty)
                     *hasProperty = true;
-                return Object::getValue(*receiver, pd->value, attrs);
+                return Object::getValue(receiver, pd->value, attrs);
             }
             if (o->internalClass->vtable->type == Type_StringObject) {
                 ScopedString str(scope, static_cast<Heap::StringObject *>(o)->getIndex(index));
@@ -436,7 +437,7 @@ ReturnedValue Object::internalGet(PropertyKey id, const Value *receiver, bool *h
             if (idx.isValid()) {
                 if (hasProperty)
                     *hasProperty = true;
-                return Object::getValue(*receiver, *o->propertyData(idx.index), idx.attrs);
+                return Object::getValue(receiver, *o->propertyData(idx.index), idx.attrs);
             }
             o = o->prototype();
             if (!o || o->internalClass->vtable->get != Object::virtualGet)
diff --git a/src/qml/jsruntime/qv4object_p.h b/src/qml/jsruntime/qv4object_p.h
index 38055ef407..f3375929a3 100644
--- a/src/qml/jsruntime/qv4object_p.h
+++ b/src/qml/jsruntime/qv4object_p.h
@@ -185,22 +185,22 @@ struct Q_QML_EXPORT Object: Managed {
     //
     // helpers
     //
-    static ReturnedValue getValue(const Value &thisObject, const Value &v, PropertyAttributes attrs) {
+    static ReturnedValue getValue(const Value *thisObject, const Value &v, PropertyAttributes attrs) {
         if (attrs.isData())
             return v.asReturnedValue();
         return getValueAccessor(thisObject, v, attrs);
     }
     ReturnedValue getValue(const Value &v, PropertyAttributes attrs) const {
-        return getValue(*this, v, attrs);
+        return getValue(this, v, attrs);
     }
     ReturnedValue getValueByIndex(uint propertyIndex) const {
         PropertyAttributes attrs = internalClass()->propertyData.at(propertyIndex);
         const Value *v = propertyData(propertyIndex);
         if (!attrs.isAccessor())
             return v->asReturnedValue();
-        return getValueAccessor(*this, *v, attrs);
+        return getValueAccessor(this, *v, attrs);
     }
-    static ReturnedValue getValueAccessor(const Value &thisObject, const Value &v, PropertyAttributes attrs);
+    static ReturnedValue getValueAccessor(const Value *thisObject, const Value &v, PropertyAttributes attrs);
 
     bool putValue(uint memberIndex, PropertyAttributes attrs, const Value &value);
 
@@ -543,13 +543,11 @@ inline const ArrayObject *Value::as() const {
     return isManaged() && m()->internalClass->vtable->type == Managed::Type_ArrayObject ? static_cast<const ArrayObject *>(this) : nullptr;
 }
 
-#ifndef V4_BOOTSTRAP
 template<>
 inline ReturnedValue value_convert<Object>(ExecutionEngine *e, const Value &v)
 {
     return v.toObject(e)->asReturnedValue();
 }
-#endif
 
 }
 
diff --git a/src/qml/jsruntime/qv4objectproto_p.h b/src/qml/jsruntime/qv4objectproto_p.h
index e9515b5b68..8707305dc2 100644
--- a/src/qml/jsruntime/qv4objectproto_p.h
+++ b/src/qml/jsruntime/qv4objectproto_p.h
@@ -74,7 +74,7 @@ struct ObjectCtor: FunctionObject
     static ReturnedValue virtualCall(const FunctionObject *m, const Value *thisObject, const Value *argv, int argc);
 };
 
-struct ObjectPrototype: Object
+struct Q_QML_PRIVATE_EXPORT ObjectPrototype: Object
 {
     void init(ExecutionEngine *engine, Object *ctor);
 
diff --git a/src/qml/jsruntime/qv4profiling.cpp b/src/qml/jsruntime/qv4profiling.cpp
index b337243204..26e1074fe3 100644
--- a/src/qml/jsruntime/qv4profiling.cpp
+++ b/src/qml/jsruntime/qv4profiling.cpp
@@ -49,7 +49,7 @@ namespace Profiling {
 FunctionLocation FunctionCall::resolveLocation() const
 {
     return FunctionLocation(m_function->name()->toQString(),
-                            m_function->compilationUnit->fileName(),
+                            m_function->executableCompilationUnit()->fileName(),
                             m_function->compiledFunction->location.line,
                             m_function->compiledFunction->location.column);
 }
diff --git a/src/qml/jsruntime/qv4profiling_p.h b/src/qml/jsruntime/qv4profiling_p.h
index 8461384e9a..ccf7c9210d 100644
--- a/src/qml/jsruntime/qv4profiling_p.h
+++ b/src/qml/jsruntime/qv4profiling_p.h
@@ -144,19 +144,19 @@ public:
 
     FunctionCall(Function *function, qint64 start, qint64 end) :
         m_function(function), m_start(start), m_end(end)
-    { m_function->compilationUnit->addref(); }
+    { m_function->executableCompilationUnit()->addref(); }
 
     FunctionCall(const FunctionCall &other) :
         m_function(other.m_function), m_start(other.m_start), m_end(other.m_end)
-    { m_function->compilationUnit->addref(); }
+    { m_function->executableCompilationUnit()->addref(); }
 
     ~FunctionCall()
-    { m_function->compilationUnit->release(); }
+    { m_function->executableCompilationUnit()->release(); }
 
     FunctionCall &operator=(const FunctionCall &other) {
         if (&other != this) {
-            other.m_function->compilationUnit->addref();
-            m_function->compilationUnit->release();
+            other.m_function->executableCompilationUnit()->addref();
+            m_function->executableCompilationUnit()->release();
             m_function = other.m_function;
             m_start = other.m_start;
             m_end = other.m_end;
@@ -189,22 +189,22 @@ public:
         SentMarker(const SentMarker &other) : m_function(other.m_function)
         {
             if (m_function)
-                m_function->compilationUnit->addref();
+                m_function->executableCompilationUnit()->addref();
         }
 
         ~SentMarker()
         {
             if (m_function)
-                m_function->compilationUnit->release();
+                m_function->executableCompilationUnit()->release();
         }
 
         SentMarker &operator=(const SentMarker &other)
         {
             if (&other != this) {
                 if (m_function)
-                    m_function->compilationUnit->release();
+                    m_function->executableCompilationUnit()->release();
                 m_function = other.m_function;
-                m_function->compilationUnit->addref();
+                m_function->executableCompilationUnit()->addref();
             }
             return *this;
         }
@@ -213,7 +213,7 @@ public:
         {
             Q_ASSERT(m_function == nullptr);
             m_function = function;
-            m_function->compilationUnit->addref();
+            m_function->executableCompilationUnit()->addref();
         }
 
         bool isValid() const
diff --git a/src/qml/jsruntime/qv4qobjectwrapper.cpp b/src/qml/jsruntime/qv4qobjectwrapper.cpp
index e81c90dd1a..095f27279f 100644
--- a/src/qml/jsruntime/qv4qobjectwrapper.cpp
+++ b/src/qml/jsruntime/qv4qobjectwrapper.cpp
@@ -763,6 +763,8 @@ struct QObjectWrapperOwnPropertyKeyIterator : ObjectOwnPropertyKeyIterator
     ~QObjectWrapperOwnPropertyKeyIterator() override = default;
     PropertyKey next(const QV4::Object *o, Property *pd = nullptr, PropertyAttributes *attrs = nullptr) override;
 
+private:
+    QSet<QByteArray> m_alreadySeen;
 };
 
 PropertyKey QObjectWrapperOwnPropertyKeyIterator::next(const QV4::Object *o, Property *pd, PropertyAttributes *attrs)
@@ -803,6 +805,11 @@ PropertyKey QObjectWrapperOwnPropertyKeyIterator::next(const QV4::Object *o, Pro
             ++propertyIndex;
             if (method.access() == QMetaMethod::Private || (preventDestruction && (index == deleteLaterIdx || index == destroyedIdx1 || index == destroyedIdx2)))
                 continue;
+            // filter out duplicates due to overloads:
+            if (m_alreadySeen.contains(method.name()))
+                continue;
+            else
+                m_alreadySeen.insert(method.name());
             ExecutionEngine *thatEngine = that->engine();
             Scope scope(thatEngine);
             ScopedString methodName(scope, thatEngine->newString(QString::fromUtf8(method.name())));
diff --git a/src/qml/jsruntime/qv4regexpobject.cpp b/src/qml/jsruntime/qv4regexpobject.cpp
index 5bd25dcbec..64aba1d85c 100644
--- a/src/qml/jsruntime/qv4regexpobject.cpp
+++ b/src/qml/jsruntime/qv4regexpobject.cpp
@@ -198,13 +198,6 @@ QString RegExpObject::toString() const
     return p;
 }
 
-QString RegExpObject::source() const
-{
-    Scope scope(engine());
-    ScopedValue s(scope, get(scope.engine->id_source()));
-    return s->toQString();
-}
-
 ReturnedValue RegExpObject::builtinExec(ExecutionEngine *engine, const String *str)
 {
     QString s = str->toQString();
diff --git a/src/qml/jsruntime/qv4regexpobject_p.h b/src/qml/jsruntime/qv4regexpobject_p.h
index 04b533e49d..b94889e9f0 100644
--- a/src/qml/jsruntime/qv4regexpobject_p.h
+++ b/src/qml/jsruntime/qv4regexpobject_p.h
@@ -101,7 +101,7 @@ DECLARE_HEAP_OBJECT(RegExpCtor, FunctionObject) {
 
 }
 
-struct RegExpObject: Object {
+struct Q_QML_PRIVATE_EXPORT RegExpObject: Object {
     V4_OBJECT2(RegExpObject, Object)
     Q_MANAGED_TYPE(RegExpObject)
     V4_INTERNALCLASS(RegExpObject)
@@ -145,7 +145,12 @@ struct RegExpObject: Object {
     QRegularExpression toQRegularExpression() const;
 #endif
     QString toString() const;
-    QString source() const;
+    QString source() const
+    {
+        Scope scope(engine());
+        ScopedValue s(scope, get(scope.engine->id_source()));
+        return s->toQString();
+    }
 
     Heap::RegExp *value() const { return d()->value; }
     uint flags() const { return d()->value->flags; }
diff --git a/src/qml/jsruntime/qv4runtime.cpp b/src/qml/jsruntime/qv4runtime.cpp
index e95dfa775f..478114a38a 100644
--- a/src/qml/jsruntime/qv4runtime.cpp
+++ b/src/qml/jsruntime/qv4runtime.cpp
@@ -38,9 +38,9 @@
 ****************************************************************************/
 
 #include "qv4global_p.h"
-#include "qv4engine_p.h"
 #include "qv4runtime_p.h"
 #ifndef V4_BOOTSTRAP
+#include "qv4engine_p.h"
 #include "qv4object_p.h"
 #include "qv4objectproto_p.h"
 #include "qv4globalobject_p.h"
@@ -224,6 +224,11 @@ void RuntimeCounters::count(const char *func, uint tag1, uint tag2)
 
 #ifndef V4_BOOTSTRAP
 
+static QV4::Lookup *runtimeLookup(Function *f, uint i)
+{
+    return f->executableCompilationUnit()->runtimeLookups + i;
+}
+
 void RuntimeHelpers::numberToString(QString *result, double num, int radix)
 {
     Q_ASSERT(result);
@@ -314,7 +319,8 @@ void RuntimeHelpers::numberToString(QString *result, double num, int radix)
 
 ReturnedValue Runtime::Closure::call(ExecutionEngine *engine, int functionId)
 {
-    QV4::Function *clos = static_cast<CompiledData::CompilationUnit*>(engine->currentStackFrame->v4Function->compilationUnit)->runtimeFunctions[functionId];
+    QV4::Function *clos = engine->currentStackFrame->v4Function->executableCompilationUnit()
+                                  ->runtimeFunctions[functionId];
     Q_ASSERT(clos);
     ExecutionContext *current = static_cast<ExecutionContext *>(&engine->currentStackFrame->jsFrame->context);
     if (clos->isGenerator())
@@ -620,7 +626,7 @@ QV4::ReturnedValue RuntimeHelpers::addHelper(ExecutionEngine *engine, const Valu
 
 ReturnedValue Runtime::GetTemplateObject::call(Function *function, int index)
 {
-    return function->compilationUnit->templateObjectAt(index)->asReturnedValue();
+    return function->executableCompilationUnit()->templateObjectAt(index)->asReturnedValue();
 }
 
 void Runtime::StoreProperty::call(ExecutionEngine *engine, const Value &object, int nameIndex, const Value &value)
@@ -1077,33 +1083,33 @@ void Runtime::StoreSuperProperty::call(ExecutionEngine *engine, const Value &pro
 
 ReturnedValue Runtime::LoadGlobalLookup::call(ExecutionEngine *engine, Function *f, int index)
 {
-    Lookup *l = f->compilationUnit->runtimeLookups + index;
+    Lookup *l = runtimeLookup(f, index);
     return l->globalGetter(l, engine);
 }
 
 ReturnedValue Runtime::LoadQmlContextPropertyLookup::call(ExecutionEngine *engine, uint index)
 {
-    Lookup *l = engine->currentStackFrame->v4Function->compilationUnit->runtimeLookups + index;
+    Lookup *l = runtimeLookup(engine->currentStackFrame->v4Function, index);
     return l->qmlContextPropertyGetter(l, engine, nullptr);
 }
 
 ReturnedValue Runtime::GetLookup::call(ExecutionEngine *engine, Function *f, const Value &base, int index)
 {
-    Lookup *l = f->compilationUnit->runtimeLookups + index;
+    Lookup *l = runtimeLookup(f, index);
     return l->getter(l, engine, base);
 }
 
 void Runtime::SetLookupSloppy::call(Function *f, const Value &base, int index, const Value &value)
 {
     ExecutionEngine *engine = f->internalClass->engine;
-    QV4::Lookup *l = f->compilationUnit->runtimeLookups + index;
+    QV4::Lookup *l = runtimeLookup(f, index);
     l->setter(l, engine, const_cast<Value &>(base), value);
 }
 
 void Runtime::SetLookupStrict::call(Function *f, const Value &base, int index, const Value &value)
 {
     ExecutionEngine *engine = f->internalClass->engine;
-    QV4::Lookup *l = f->compilationUnit->runtimeLookups + index;
+    QV4::Lookup *l = runtimeLookup(f, index);
     if (!l->setter(l, engine, const_cast<Value &>(base), value))
         engine->throwTypeError();
 }
@@ -1175,8 +1181,14 @@ Bool RuntimeHelpers::strictEqual(const Value &x, const Value &y)
 
     if (x.isNumber())
         return y.isNumber() && x.asDouble() == y.asDouble();
-    if (x.isManaged())
+    if (x.isManaged()) {
+#ifdef V4_BOOTSTRAP
+        Q_UNIMPLEMENTED();
+        return false;
+#else
         return y.isManaged() && x.cast<Managed>()->isEqualTo(y.cast<Managed>());
+#endif
+    }
     return false;
 }
 
@@ -1360,12 +1372,13 @@ static ReturnedValue throwPropertyIsNotAFunctionTypeError(ExecutionEngine *engin
 ReturnedValue Runtime::CallGlobalLookup::call(ExecutionEngine *engine, uint index, Value argv[], int argc)
 {
     Scope scope(engine);
-    Lookup *l = engine->currentStackFrame->v4Function->compilationUnit->runtimeLookups + index;
+    Lookup *l = runtimeLookup(engine->currentStackFrame->v4Function, index);
     Value function = Value::fromReturnedValue(l->globalGetter(l, engine));
     Value thisObject = Value::undefinedValue();
-    if (!function.isFunctionObject())
+    if (!function.isFunctionObject()) {
         return throwPropertyIsNotAFunctionTypeError(engine, &thisObject,
                                                     engine->currentStackFrame->v4Function->compilationUnit->runtimeStrings[l->nameIndex]->toQString());
+    }
 
     return static_cast<FunctionObject &>(function).call(&thisObject, argv, argc);
 }
@@ -1375,11 +1388,12 @@ ReturnedValue Runtime::CallQmlContextPropertyLookup::call(ExecutionEngine *engin
 {
     Scope scope(engine);
     ScopedValue thisObject(scope);
-    Lookup *l = engine->currentStackFrame->v4Function->compilationUnit->runtimeLookups + index;
+    Lookup *l = runtimeLookup(engine->currentStackFrame->v4Function, index);
     Value function = Value::fromReturnedValue(l->qmlContextPropertyGetter(l, engine, thisObject));
-    if (!function.isFunctionObject())
+    if (!function.isFunctionObject()) {
         return throwPropertyIsNotAFunctionTypeError(engine, thisObject,
                                                     engine->currentStackFrame->v4Function->compilationUnit->runtimeStrings[l->nameIndex]->toQString());
+    }
 
     return static_cast<FunctionObject &>(function).call(thisObject, argv, argc);
 }
@@ -1414,9 +1428,11 @@ ReturnedValue Runtime::CallName::call(ExecutionEngine *engine, int nameIndex, Va
     if (engine->hasException)
         return Encode::undefined();
 
-    if (!f)
-        return throwPropertyIsNotAFunctionTypeError(engine, thisObject,
-                                                    engine->currentStackFrame->v4Function->compilationUnit->runtimeStrings[nameIndex]->toQString());
+    if (!f) {
+        return throwPropertyIsNotAFunctionTypeError(
+                engine, thisObject, engine->currentStackFrame->v4Function->compilationUnit
+                                            ->runtimeStrings[nameIndex]->toQString());
+    }
 
     return f->call(thisObject, argv, argc);
 }
@@ -1425,7 +1441,9 @@ ReturnedValue Runtime::CallProperty::call(ExecutionEngine *engine, const Value &
 {
     const Value *base = &baseRef;
     Scope scope(engine);
-    ScopedString name(scope, engine->currentStackFrame->v4Function->compilationUnit->runtimeStrings[nameIndex]);
+    ScopedString name(
+            scope,
+            engine->currentStackFrame->v4Function->compilationUnit->runtimeStrings[nameIndex]);
     ScopedObject lookupObject(scope, base);
 
     if (!lookupObject) {
@@ -1463,7 +1481,7 @@ ReturnedValue Runtime::CallProperty::call(ExecutionEngine *engine, const Value &
 
 ReturnedValue Runtime::CallPropertyLookup::call(ExecutionEngine *engine, const Value &base, uint index, Value *argv, int argc)
 {
-    Lookup *l = engine->currentStackFrame->v4Function->compilationUnit->runtimeLookups + index;
+    Lookup *l = runtimeLookup(engine->currentStackFrame->v4Function, index);
     // ok to have the value on the stack here
     Value f = Value::fromReturnedValue(l->getter(l, engine, base));
 
@@ -1783,7 +1801,8 @@ ReturnedValue Runtime::ObjectLiteral::call(ExecutionEngine *engine, int classId,
         if (arg != ObjectLiteralArgument::Value) {
             Q_ASSERT(args[2].isInteger());
             int functionId = args[2].integerValue();
-            QV4::Function *clos = static_cast<CompiledData::CompilationUnit*>(engine->currentStackFrame->v4Function->compilationUnit)->runtimeFunctions[functionId];
+            QV4::Function *clos = engine->currentStackFrame->v4Function->executableCompilationUnit()
+                                          ->runtimeFunctions[functionId];
             Q_ASSERT(clos);
 
             PropertyKey::FunctionNamePrefix prefix = PropertyKey::None;
@@ -1827,7 +1846,8 @@ ReturnedValue Runtime::ObjectLiteral::call(ExecutionEngine *engine, int classId,
 ReturnedValue Runtime::CreateClass::call(ExecutionEngine *engine, int classIndex,
                                           const Value &superClass, Value computedNames[])
 {
-    const CompiledData::CompilationUnit *unit = engine->currentStackFrame->v4Function->compilationUnit;
+    const QV4::ExecutableCompilationUnit *unit
+            = engine->currentStackFrame->v4Function->executableCompilationUnit();
     const QV4::CompiledData::Class *cls = unit->unitData()->classAt(classIndex);
 
     Scope scope(engine);
@@ -2170,6 +2190,7 @@ ReturnedValue Runtime::LessEqual::call(const Value &left, const Value &right)
     return Encode(r);
 }
 
+#ifndef V4_BOOTSTRAP
 struct LazyScope
 {
     ExecutionEngine *engine = nullptr;
@@ -2189,6 +2210,7 @@ struct LazyScope
         **scopedValue = value;
     }
 };
+#endif
 
 Bool Runtime::CompareEqual::call(const Value &left, const Value &right)
 {
diff --git a/src/qml/jsruntime/qv4runtime_p.h b/src/qml/jsruntime/qv4runtime_p.h
index 72af90d1dc..349099f8d5 100644
--- a/src/qml/jsruntime/qv4runtime_p.h
+++ b/src/qml/jsruntime/qv4runtime_p.h
@@ -52,8 +52,6 @@
 
 #include "qv4global_p.h"
 #include "qv4value_p.h"
-#include "qv4context_p.h"
-#include "qv4engine_p.h"
 #include "qv4math_p.h"
 #include "qv4runtimeapi_p.h"
 #include <QtCore/qnumeric.h>
diff --git a/src/qml/jsruntime/qv4runtimecodegen.cpp b/src/qml/jsruntime/qv4runtimecodegen.cpp
index 9866966936..99d0de5ec6 100644
--- a/src/qml/jsruntime/qv4runtimecodegen.cpp
+++ b/src/qml/jsruntime/qv4runtimecodegen.cpp
@@ -37,6 +37,7 @@
 **
 ****************************************************************************/
 
+#include "qv4engine_p.h"
 #include "qv4runtimecodegen_p.h"
 #include "qv4compilerscanfunctions_p.h"
 
diff --git a/src/qml/jsruntime/qv4script.cpp b/src/qml/jsruntime/qv4script.cpp
index 6cb2e95cdc..ee7f4dff0b 100644
--- a/src/qml/jsruntime/qv4script.cpp
+++ b/src/qml/jsruntime/qv4script.cpp
@@ -61,7 +61,7 @@
 
 using namespace QV4;
 
-Script::Script(ExecutionEngine *v4, QmlContext *qml, const QQmlRefPointer<CompiledData::CompilationUnit> &compilationUnit)
+Script::Script(ExecutionEngine *v4, QmlContext *qml, const QQmlRefPointer<ExecutableCompilationUnit> &compilationUnit)
     : line(1), column(0), context(v4->rootContext()), strictMode(false), inheritContext(true), parsed(false)
     , compilationUnit(compilationUnit), vmFunction(nullptr), parseAsBinding(true)
 {
@@ -133,7 +133,7 @@ void Script::parse()
         if (v4->hasException)
             return;
 
-        compilationUnit = cg.generateCompilationUnit();
+        compilationUnit = QV4::ExecutableCompilationUnit::create(cg.generateCompilationUnit());
         vmFunction = compilationUnit->linkToEngine(v4);
     }
 
@@ -172,10 +172,11 @@ Function *Script::function()
     return vmFunction;
 }
 
-QQmlRefPointer<QV4::CompiledData::CompilationUnit> Script::precompile(QV4::Compiler::Module *module, QQmlJS::Engine *jsEngine, Compiler::JSUnitGenerator *unitGenerator,
-                                                                      const QString &fileName, const QString &finalUrl, const QString &source,
-                                                                      QList<QQmlError> *reportedErrors,
-                                                                      QV4::Compiler::ContextType contextType)
+QV4::CompiledData::CompilationUnit Script::precompile(
+        QV4::Compiler::Module *module, QQmlJS::Engine *jsEngine,
+        Compiler::JSUnitGenerator *unitGenerator, const QString &fileName, const QString &finalUrl,
+        const QString &source, QList<QQmlError> *reportedErrors,
+        QV4::Compiler::ContextType contextType)
 {
     using namespace QV4::Compiler;
     using namespace QQmlJS::AST;
@@ -219,8 +220,9 @@ Script *Script::createFromFileOrCache(ExecutionEngine *engine, QmlContext *qmlCo
 
     QQmlMetaType::CachedUnitLookupError cacheError = QQmlMetaType::CachedUnitLookupError::NoError;
     if (const QV4::CompiledData::Unit *cachedUnit = QQmlMetaType::findCachedCompilationUnit(originalUrl, &cacheError)) {
-        QQmlRefPointer<QV4::CompiledData::CompilationUnit> jsUnit;
-        jsUnit.adopt(new QV4::CompiledData::CompilationUnit(cachedUnit));
+        QQmlRefPointer<QV4::ExecutableCompilationUnit> jsUnit
+                = QV4::ExecutableCompilationUnit::create(
+                        QV4::CompiledData::CompilationUnit(cachedUnit));
         return new QV4::Script(engine, qmlContext, jsUnit);
     }
 
diff --git a/src/qml/jsruntime/qv4script_p.h b/src/qml/jsruntime/qv4script_p.h
index a1e9b83a8b..aecedea701 100644
--- a/src/qml/jsruntime/qv4script_p.h
+++ b/src/qml/jsruntime/qv4script_p.h
@@ -80,7 +80,7 @@ struct Q_QML_EXPORT Script {
         if (qml)
             qmlContext.set(engine, *qml);
     }
-    Script(ExecutionEngine *engine, QmlContext *qml, const QQmlRefPointer<CompiledData::CompilationUnit> &compilationUnit);
+    Script(ExecutionEngine *engine, QmlContext *qml, const QQmlRefPointer<ExecutableCompilationUnit> &compilationUnit);
     ~Script();
     QString sourceFile;
     int line;
@@ -92,7 +92,7 @@ struct Q_QML_EXPORT Script {
     bool parsed;
     QV4::Compiler::ContextType contextType = QV4::Compiler::ContextType::Eval;
     QV4::PersistentValue qmlContext;
-    QQmlRefPointer<CompiledData::CompilationUnit> compilationUnit;
+    QQmlRefPointer<ExecutableCompilationUnit> compilationUnit;
     Function *vmFunction;
     bool parseAsBinding;
 
@@ -101,8 +101,10 @@ struct Q_QML_EXPORT Script {
 
     Function *function();
 
-    static QQmlRefPointer<CompiledData::CompilationUnit> precompile(QV4::Compiler::Module *module, QQmlJS::Engine *jsEngine, Compiler::JSUnitGenerator *unitGenerator,
-            const QString &fileName, const QString &finalUrl, const QString &source,
+    static QV4::CompiledData::CompilationUnit precompile(
+            QV4::Compiler::Module *module, QQmlJS::Engine *jsEngine,
+            Compiler::JSUnitGenerator *unitGenerator, const QString &fileName,
+            const QString &finalUrl, const QString &source,
             QList<QQmlError> *reportedErrors = nullptr,
             QV4::Compiler::ContextType contextType = QV4::Compiler::ContextType::Global);
     static Script *createFromFileOrCache(ExecutionEngine *engine, QmlContext *qmlContext, const QString &fileName, const QUrl &originalUrl, QString *error);
diff --git a/src/qml/jsruntime/qv4sequenceobject_p.h b/src/qml/jsruntime/qv4sequenceobject_p.h
index da71215bed..886dfaa521 100644
--- a/src/qml/jsruntime/qv4sequenceobject_p.h
+++ b/src/qml/jsruntime/qv4sequenceobject_p.h
@@ -65,7 +65,7 @@ QT_BEGIN_NAMESPACE
 
 namespace QV4 {
 
-struct SequencePrototype : public QV4::Object
+struct Q_QML_PRIVATE_EXPORT SequencePrototype : public QV4::Object
 {
     V4_PROTOTYPE(arrayPrototype)
     void init();
diff --git a/src/qml/jsruntime/qv4stackframe_p.h b/src/qml/jsruntime/qv4stackframe_p.h
index 44cfef9173..bf689a74bc 100644
--- a/src/qml/jsruntime/qv4stackframe_p.h
+++ b/src/qml/jsruntime/qv4stackframe_p.h
@@ -52,63 +52,13 @@
 
 #include <private/qv4context_p.h>
 #include <private/qv4enginebase_p.h>
-#ifndef V4_BOOTSTRAP
+#include <private/qv4calldata_p.h>
 #include <private/qv4function_p.h>
-#endif
 
 QT_BEGIN_NAMESPACE
 
 namespace QV4 {
 
-struct CallData
-{
-    enum Offsets {
-        Function = 0,
-        Context = 1,
-        Accumulator = 2,
-        This = 3,
-        NewTarget = 4,
-        Argc = 5,
-
-        LastOffset = Argc,
-        OffsetCount = LastOffset + 1
-    };
-
-    Value function;
-    Value context;
-    Value accumulator;
-    Value thisObject;
-    Value newTarget;
-    Value _argc;
-
-    int argc() const {
-        Q_ASSERT(_argc.isInteger());
-        return _argc.int_32();
-    }
-
-    void setArgc(int argc) {
-        Q_ASSERT(argc >= 0);
-        _argc.setInt_32(argc);
-    }
-
-    inline ReturnedValue argument(int i) const {
-        return i < argc() ? args[i].asReturnedValue() : Value::undefinedValue().asReturnedValue();
-    }
-
-    Value args[1];
-
-    static Q_DECL_CONSTEXPR int HeaderSize() { return offsetof(CallData, args) / sizeof(QV4::Value); }
-};
-
-Q_STATIC_ASSERT(std::is_standard_layout<CallData>::value);
-Q_STATIC_ASSERT(offsetof(CallData, function   ) == CallData::Function    * sizeof(Value));
-Q_STATIC_ASSERT(offsetof(CallData, context    ) == CallData::Context     * sizeof(Value));
-Q_STATIC_ASSERT(offsetof(CallData, accumulator) == CallData::Accumulator * sizeof(Value));
-Q_STATIC_ASSERT(offsetof(CallData, thisObject ) == CallData::This        * sizeof(Value));
-Q_STATIC_ASSERT(offsetof(CallData, newTarget  ) == CallData::NewTarget   * sizeof(Value));
-Q_STATIC_ASSERT(offsetof(CallData, _argc      ) == CallData::Argc        * sizeof(Value));
-Q_STATIC_ASSERT(offsetof(CallData, args       ) == 6 * sizeof(Value));
-
 struct Q_QML_EXPORT CppStackFrame {
     EngineBase *engine;
     Value *savedStackTop;
@@ -155,7 +105,6 @@ struct Q_QML_EXPORT CppStackFrame {
         engine->jsStackTop = savedStackTop;
     }
 
-#ifndef V4_BOOTSTRAP
     static uint requiredJSStackFrameSize(uint nRegisters) {
         return CallData::HeaderSize() + nRegisters;
     }
@@ -198,7 +147,6 @@ struct Q_QML_EXPORT CppStackFrame {
                 *v = Value::emptyValue().asReturnedValue();
         }
     }
-#endif
 
     QString source() const;
     QString function() const;
diff --git a/src/qml/jsruntime/qv4string.cpp b/src/qml/jsruntime/qv4string.cpp
index 68d65f2e24..223f4a4769 100644
--- a/src/qml/jsruntime/qv4string.cpp
+++ b/src/qml/jsruntime/qv4string.cpp
@@ -39,19 +39,15 @@
 
 #include "qv4string_p.h"
 #include "qv4value_p.h"
-#ifndef V4_BOOTSTRAP
 #include "qv4identifiertable_p.h"
 #include "qv4runtime_p.h"
 #include "qv4objectproto_p.h"
 #include "qv4stringobject_p.h"
-#endif
 #include <QtCore/QHash>
 #include <QtCore/private/qnumeric_p.h>
 
 using namespace QV4;
 
-#ifndef V4_BOOTSTRAP
-
 void Heap::StringOrSymbol::markObjects(Heap::Base *that, MarkStack *markStack)
 {
     StringOrSymbol *s = static_cast<StringOrSymbol *>(that);
@@ -254,10 +250,3 @@ qint64 String::virtualGetLength(const Managed *m)
 {
     return static_cast<const String *>(m)->d()->length();
 }
-
-#endif // V4_BOOTSTRAP
-
-uint String::toArrayIndex(const QString &str)
-{
-    return QV4::String::toArrayIndex(str.constData(), str.constData() + str.length());
-}
diff --git a/src/qml/jsruntime/qv4string_p.h b/src/qml/jsruntime/qv4string_p.h
index fbd4f5f550..7888809490 100644
--- a/src/qml/jsruntime/qv4string_p.h
+++ b/src/qml/jsruntime/qv4string_p.h
@@ -54,6 +54,7 @@
 #include "qv4managed_p.h"
 #include <QtCore/private/qnumeric_p.h>
 #include "qv4enginebase_p.h"
+#include "qv4stringtoarrayindex_p.h"
 
 QT_BEGIN_NAMESPACE
 
@@ -104,7 +105,6 @@ struct Q_QML_PRIVATE_EXPORT StringOrSymbol : Base
 struct Q_QML_PRIVATE_EXPORT String : StringOrSymbol {
     static void markObjects(Heap::Base *that, MarkStack *markStack);
 
-#ifndef V4_BOOTSTRAP
     const VTable *vtable() const {
         return internalClass->vtable;
     }
@@ -140,11 +140,9 @@ struct Q_QML_PRIVATE_EXPORT String : StringOrSymbol {
 
 private:
     static void append(const String *data, QChar *ch);
-#endif
 };
 Q_STATIC_ASSERT(std::is_trivial< String >::value);
 
-#ifndef V4_BOOTSTRAP
 struct ComplexString : String {
     void init(String *l, String *n);
     void init(String *ref, int from, int len);
@@ -162,12 +160,10 @@ inline
 int String::length() const {
     return text ? text->size : static_cast<const ComplexString *>(this)->len;
 }
-#endif
 
 }
 
 struct Q_QML_PRIVATE_EXPORT StringOrSymbol : public Managed {
-#ifndef V4_BOOTSTRAP
     V4_MANAGED(StringOrSymbol, Managed)
     V4_NEEDS_DESTROY
     enum {
@@ -184,11 +180,9 @@ public:
     inline QString toQString() const {
         return d()->toQString();
     }
-#endif
 };
 
 struct Q_QML_PRIVATE_EXPORT String : public StringOrSymbol {
-#ifndef V4_BOOTSTRAP
     V4_MANAGED(String, StringOrSymbol)
     Q_MANAGED_TYPE(String)
     V4_INTERNALCLASS(String)
@@ -239,43 +233,13 @@ struct Q_QML_PRIVATE_EXPORT String : public StringOrSymbol {
 protected:
     static bool virtualIsEqualTo(Managed *that, Managed *o);
     static qint64 virtualGetLength(const Managed *m);
-#endif
-
-public:
-    static uint toArrayIndex(const QString &str);
-
-private:
-    static inline uint toUInt(const QChar *ch) { return ch->unicode(); }
-    static inline uint toUInt(const char *ch) { return static_cast<unsigned char>(*ch); }
-
-    template <typename T>
-    static inline uint toArrayIndex(const T *ch, const T *end)
-    {
-        uint i = toUInt(ch) - '0';
-        if (i > 9)
-            return UINT_MAX;
-        ++ch;
-        // reject "01", "001", ...
-        if (i == 0 && ch != end)
-            return UINT_MAX;
-
-        while (ch < end) {
-            uint x = toUInt(ch) - '0';
-            if (x > 9)
-                return UINT_MAX;
-            if (mul_overflow(i, uint(10), &i) || add_overflow(i, x, &i)) // i = i * 10 + x
-                return UINT_MAX;
-            ++ch;
-        }
-        return i;
-    }
 
 public:
     template <typename T>
     static inline uint calculateHashValue(const T *ch, const T* end, uint *subtype)
     {
         // array indices get their number as hash value
-        uint h = toArrayIndex(ch, end);
+        uint h = stringToArrayIndex(ch, end);
         if (h != UINT_MAX) {
             if (subtype)
                 *subtype = Heap::StringOrSymbol::StringType_ArrayIndex;
@@ -283,17 +247,16 @@ public:
         }
 
         while (ch < end) {
-            h = 31 * h + toUInt(ch);
+            h = 31 * h + charToUInt(ch);
             ++ch;
         }
 
         if (subtype)
-            *subtype = (toUInt(ch) == '@') ? Heap::StringOrSymbol::StringType_Symbol : Heap::StringOrSymbol::StringType_Regular;
+            *subtype = (charToUInt(ch) == '@') ? Heap::StringOrSymbol::StringType_Symbol : Heap::StringOrSymbol::StringType_Regular;
         return h;
     }
 };
 
-#ifndef V4_BOOTSTRAP
 struct ComplexString : String {
     typedef QV4::Heap::ComplexString Data;
     QV4::Heap::ComplexString *d_unchecked() const { return static_cast<QV4::Heap::ComplexString *>(m()); }
@@ -332,8 +295,6 @@ inline ReturnedValue value_convert<String>(ExecutionEngine *e, const Value &v)
 {
     return v.toString(e)->asReturnedValue();
 }
-#endif
-
 
 }
 
diff --git a/src/qml/jsruntime/qv4stringtoarrayindex_p.h b/src/qml/jsruntime/qv4stringtoarrayindex_p.h
new file mode 100644
index 0000000000..61bd988d1e
--- /dev/null
+++ b/src/qml/jsruntime/qv4stringtoarrayindex_p.h
@@ -0,0 +1,96 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtQml module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QV4STRINGTOARRAYINDEX_P_H
+#define QV4STRINGTOARRAYINDEX_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <QtCore/private/qnumeric_p.h>
+#include <QtCore/qstring.h>
+#include <limits>
+
+QT_BEGIN_NAMESPACE
+
+namespace QV4 {
+
+inline uint charToUInt(const QChar *ch) { return ch->unicode(); }
+inline uint charToUInt(const char *ch) { return static_cast<unsigned char>(*ch); }
+
+template <typename T>
+uint stringToArrayIndex(const T *ch, const T *end)
+{
+    uint i = charToUInt(ch) - '0';
+    if (i > 9)
+        return std::numeric_limits<uint>::max();
+    ++ch;
+    // reject "01", "001", ...
+    if (i == 0 && ch != end)
+        return std::numeric_limits<uint>::max();
+
+    while (ch < end) {
+        uint x = charToUInt(ch) - '0';
+        if (x > 9)
+            return std::numeric_limits<uint>::max();
+        if (mul_overflow(i, uint(10), &i) || add_overflow(i, x, &i)) // i = i * 10 + x
+            return std::numeric_limits<uint>::max();
+        ++ch;
+    }
+    return i;
+}
+
+inline uint stringToArrayIndex(const QString &str)
+{
+    return stringToArrayIndex(str.constData(), str.constData() + str.length());
+}
+
+} // namespace QV4
+
+QT_END_NAMESPACE
+
+#endif // QV4STRINGTOARRAYINDEX_P_H
diff --git a/src/qml/jsruntime/qv4value.cpp b/src/qml/jsruntime/qv4value.cpp
index cbc153bb86..82cf11f148 100644
--- a/src/qml/jsruntime/qv4value.cpp
+++ b/src/qml/jsruntime/qv4value.cpp
@@ -36,11 +36,11 @@
 ** $QT_END_LICENSE$
 **
 ****************************************************************************/
-#include <qv4engine_p.h>
+
 #include <qv4runtime_p.h>
-#include <qv4string_p.h>
 #include <qv4propertykey_p.h>
 #ifndef V4_BOOTSTRAP
+#include <qv4string_p.h>
 #include <qv4symbol_p.h>
 #include <qv4object_p.h>
 #include <qv4objectproto_p.h>
@@ -248,7 +248,6 @@ QV4::PropertyKey Value::toPropertyKey(ExecutionEngine *e) const
     ScopedStringOrSymbol s(scope, v);
     return s->toPropertyKey();
 }
-#endif // V4_BOOTSTRAP
 
 bool Value::sameValue(Value other) const {
     if (_val == other._val)
@@ -285,7 +284,6 @@ bool Value::sameValueZero(Value other) const {
     return false;
 }
 
-#ifndef V4_BOOTSTRAP
 Heap::String *Value::toString(ExecutionEngine *e, Value val)
 {
     return RuntimeHelpers::convertToString(e, val);
diff --git a/src/qml/jsruntime/qv4vme_moth.cpp b/src/qml/jsruntime/qv4vme_moth.cpp
index ec44f42933..c6322fb504 100644
--- a/src/qml/jsruntime/qv4vme_moth.cpp
+++ b/src/qml/jsruntime/qv4vme_moth.cpp
@@ -65,6 +65,8 @@
 #include <private/qv4baselinejit_p.h>
 #endif
 
+#include <qtqml_tracepoints_p.h>
+
 #undef COUNT_INSTRUCTIONS
 
 enum { ShowWhenDeoptimiationHappens = 0 };
@@ -422,6 +424,10 @@ ReturnedValue VME::exec(CppStackFrame *frame, ExecutionEngine *engine)
     CHECK_STACK_LIMITS(engine);
 
     Function *function = frame->v4Function;
+    Q_TRACE_SCOPE(QQmlV4_function_call, engine, function->name()->toQString(),
+                  function->compilationUnit->fileName(),
+                  function->compiledFunction->location.line,
+                  function->compiledFunction->location.column);
     Profiling::FunctionCallProfiler profiler(engine, function); // start execution profiling
     QV4::Debugging::Debugger *debugger = engine->debugger();
 
@@ -559,14 +565,14 @@ QV4::ReturnedValue VME::interpret(CppStackFrame *frame, ExecutionEngine *engine,
 
     MOTH_BEGIN_INSTR(LoadGlobalLookup)
         STORE_IP();
-        QV4::Lookup *l = function->compilationUnit->runtimeLookups + index;
+        QV4::Lookup *l = function->executableCompilationUnit()->runtimeLookups + index;
         acc = l->globalGetter(l, engine);
         CHECK_EXCEPTION;
     MOTH_END_INSTR(LoadGlobalLookup)
 
     MOTH_BEGIN_INSTR(LoadQmlContextPropertyLookup)
         STORE_IP();
-        QV4::Lookup *l = function->compilationUnit->runtimeLookups + index;
+        QV4::Lookup *l = function->executableCompilationUnit()->runtimeLookups + index;
         acc = l->qmlContextPropertyGetter(l, engine, nullptr);
         CHECK_EXCEPTION;
     MOTH_END_INSTR(LoadQmlContextPropertyLookup)
@@ -610,7 +616,7 @@ QV4::ReturnedValue VME::interpret(CppStackFrame *frame, ExecutionEngine *engine,
         STORE_IP();
         STORE_ACC();
 
-        QV4::Lookup *l = function->compilationUnit->runtimeLookups + index;
+        QV4::Lookup *l = function->executableCompilationUnit()->runtimeLookups + index;
 
         if (accumulator.isNullOrUndefined()) {
             QString message = QStringLiteral("Cannot read property '%1' of %2")
@@ -634,7 +640,7 @@ QV4::ReturnedValue VME::interpret(CppStackFrame *frame, ExecutionEngine *engine,
     MOTH_BEGIN_INSTR(SetLookup)
         STORE_IP();
         STORE_ACC();
-        QV4::Lookup *l = function->compilationUnit->runtimeLookups + index;
+        QV4::Lookup *l = function->executableCompilationUnit()->runtimeLookups + index;
         if (!l->setter(l, engine, STACK_VALUE(base), accumulator) && function->isStrict())
             engine->throwTypeError();
         CHECK_EXCEPTION;
@@ -716,7 +722,7 @@ QV4::ReturnedValue VME::interpret(CppStackFrame *frame, ExecutionEngine *engine,
 
     MOTH_BEGIN_INSTR(CallPropertyLookup)
         STORE_IP();
-        Lookup *l = function->compilationUnit->runtimeLookups + lookupIndex;
+        Lookup *l = function->executableCompilationUnit()->runtimeLookups + lookupIndex;
 
         if (stack[base].isNullOrUndefined()) {
             QString message = QStringLiteral("Cannot call method '%1' of %2")
diff --git a/src/qml/memory/qv4mm.cpp b/src/qml/memory/qv4mm.cpp
index 34d334a24d..9288d3e3b6 100644
--- a/src/qml/memory/qv4mm.cpp
+++ b/src/qml/memory/qv4mm.cpp
@@ -63,6 +63,7 @@
 #include "qv4profiling_p.h"
 #include "qv4mapobject_p.h"
 #include "qv4setobject_p.h"
+#include "qv4writebarrier_p.h"
 
 //#define MM_STATS
 
diff --git a/src/qml/memory/qv4writebarrier_p.h b/src/qml/memory/qv4writebarrier_p.h
index 8b04aa6cb1..c65cfc0269 100644
--- a/src/qml/memory/qv4writebarrier_p.h
+++ b/src/qml/memory/qv4writebarrier_p.h
@@ -51,7 +51,6 @@
 //
 
 #include <private/qv4global_p.h>
-#include <private/qv4enginebase_p.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -60,6 +59,7 @@ QT_BEGIN_NAMESPACE
 #define WRITEBARRIER(x) (1/WRITEBARRIER_##x == 1)
 
 namespace QV4 {
+struct EngineBase;
 
 namespace WriteBarrier {
 
diff --git a/src/qml/qml.pro b/src/qml/qml.pro
index ca3282556e..5cb51e0d03 100644
--- a/src/qml/qml.pro
+++ b/src/qml/qml.pro
@@ -4,6 +4,9 @@ QT = core-private
 qtConfig(qml-network): \
     QT += network
 
+TRACEPOINT_PROVIDER = $$PWD/qtqml.tracepoints
+CONFIG += qt_tracepoints
+
 DEFINES   += QT_NO_URL_CAST_FROM_STRING QT_NO_INTEGER_EVENT_COORDINATES
 
 msvc:equals(QT_ARCH, i386): QMAKE_LFLAGS += /BASE:0x66000000
diff --git a/src/qml/qml/qqmlbinding.cpp b/src/qml/qml/qqmlbinding.cpp
index 656c7dd515..7fb15af570 100644
--- a/src/qml/qml/qqmlbinding.cpp
+++ b/src/qml/qml/qqmlbinding.cpp
@@ -335,7 +335,7 @@ protected:
 
 class QQmlTranslationBinding : public GenericBinding<QMetaType::QString> {
 public:
-    QQmlTranslationBinding(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QV4::CompiledData::Binding *binding)
+    QQmlTranslationBinding(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QV4::CompiledData::Binding *binding)
     {
         setCompilationUnit(compilationUnit);
         m_binding = binding;
@@ -356,7 +356,7 @@ public:
         if (!isAddedToObject() || hasError())
             return;
 
-        const QString result = m_binding->valueAsString(m_compilationUnit.data());
+        const QString result = m_compilationUnit->bindingValueAsString(m_binding);
 
         Q_ASSERT(targetObject());
 
@@ -378,7 +378,7 @@ private:
     const QV4::CompiledData::Binding *m_binding;
 };
 
-QQmlBinding *QQmlBinding::createTranslationBinding(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &unit, const QV4::CompiledData::Binding *binding, QObject *obj, QQmlContextData *ctxt)
+QQmlBinding *QQmlBinding::createTranslationBinding(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &unit, const QV4::CompiledData::Binding *binding, QObject *obj, QQmlContextData *ctxt)
 {
     QQmlTranslationBinding *b = new QQmlTranslationBinding(unit, binding);
 
diff --git a/src/qml/qml/qqmlbinding_p.h b/src/qml/qml/qqmlbinding_p.h
index f192de4342..85b02dcde4 100644
--- a/src/qml/qml/qqmlbinding_p.h
+++ b/src/qml/qml/qqmlbinding_p.h
@@ -79,7 +79,7 @@ public:
                                const QString &url = QString(), quint16 lineNumber = 0);
     static QQmlBinding *create(const QQmlPropertyData *property, QV4::Function *function,
                                QObject *obj, QQmlContextData *ctxt, QV4::ExecutionContext *scope);
-    static QQmlBinding *createTranslationBinding(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &unit, const QV4::CompiledData::Binding *binding,
+    static QQmlBinding *createTranslationBinding(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &unit, const QV4::CompiledData::Binding *binding,
                                                  QObject *obj, QQmlContextData *ctxt);
     ~QQmlBinding() override;
 
diff --git a/src/qml/qml/qqmlcomponent.cpp b/src/qml/qml/qqmlcomponent.cpp
index 64d2a064df..04debc0615 100644
--- a/src/qml/qml/qqmlcomponent.cpp
+++ b/src/qml/qml/qqmlcomponent.cpp
@@ -72,7 +72,7 @@ namespace {
 
 QT_BEGIN_NAMESPACE
 
-class QQmlComponentExtension : public QV8Engine::Deletable
+class QQmlComponentExtension : public QV4::ExecutionEngine::Deletable
 {
 public:
     QQmlComponentExtension(QV4::ExecutionEngine *v4);
@@ -550,7 +550,8 @@ QQmlComponent::QQmlComponent(QQmlEngine *engine, const QString &fileName,
 /*!
     \internal
 */
-QQmlComponent::QQmlComponent(QQmlEngine *engine, QV4::CompiledData::CompilationUnit *compilationUnit, int start, QObject *parent)
+QQmlComponent::QQmlComponent(QQmlEngine *engine, QV4::ExecutableCompilationUnit *compilationUnit,
+                             int start, QObject *parent)
     : QQmlComponent(engine, parent)
 {
     Q_D(QQmlComponent);
diff --git a/src/qml/qml/qqmlcomponent.h b/src/qml/qml/qqmlcomponent.h
index 20199d0b21..39b6d4526f 100644
--- a/src/qml/qml/qqmlcomponent.h
+++ b/src/qml/qml/qqmlcomponent.h
@@ -59,9 +59,7 @@ class QQmlComponentPrivate;
 class QQmlComponentAttached;
 
 namespace QV4 {
-namespace CompiledData {
-struct CompilationUnit;
-}
+class ExecutableCompilationUnit;
 }
 
 class Q_QML_EXPORT QQmlComponent : public QObject
@@ -128,7 +126,8 @@ protected:
     Q_INVOKABLE void incubateObject(QQmlV4Function *);
 
 private:
-    QQmlComponent(QQmlEngine *, QV4::CompiledData::CompilationUnit *compilationUnit, int, QObject *parent);
+    QQmlComponent(QQmlEngine *, QV4::ExecutableCompilationUnit *compilationUnit, int,
+                  QObject *parent);
 
     Q_DISABLE_COPY(QQmlComponent)
     friend class QQmlTypeData;
diff --git a/src/qml/qml/qqmlcomponent_p.h b/src/qml/qml/qqmlcomponent_p.h
index 4d9e4c6c15..71275a2cd3 100644
--- a/src/qml/qml/qqmlcomponent_p.h
+++ b/src/qml/qml/qqmlcomponent_p.h
@@ -105,7 +105,7 @@ public:
     qreal progress;
 
     int start;
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> compilationUnit;
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> compilationUnit;
 
     struct ConstructionState {
         ConstructionState()
diff --git a/src/qml/qml/qqmlcontext.cpp b/src/qml/qml/qqmlcontext.cpp
index 3710cee162..bd59409475 100644
--- a/src/qml/qml/qqmlcontext.cpp
+++ b/src/qml/qml/qqmlcontext.cpp
@@ -438,23 +438,20 @@ QUrl QQmlContext::resolvedUrl(const QUrl &src)
 
 QUrl QQmlContextData::resolvedUrl(const QUrl &src)
 {
-    QQmlContextData *ctxt = this;
-
     QUrl resolved;
     if (src.isRelative() && !src.isEmpty()) {
-        if (ctxt) {
-            while(ctxt) {
-                if (ctxt->url().isValid())
-                    break;
-                else
-                    ctxt = ctxt->parent;
-            }
-
-            if (ctxt)
-                resolved = ctxt->url().resolved(src);
-            else if (engine)
-                resolved = engine->baseUrl().resolved(src);
-        }
+        QQmlContextData *ctxt = this;
+        do {
+            if (ctxt->url().isValid())
+                break;
+            else
+                ctxt = ctxt->parent;
+        } while (ctxt);
+
+        if (ctxt)
+            resolved = ctxt->url().resolved(src);
+        else if (engine)
+            resolved = engine->baseUrl().resolved(src);
     } else {
         resolved = src;
     }
@@ -845,7 +842,7 @@ QQmlContextPrivate *QQmlContextData::asQQmlContextPrivate()
     return QQmlContextPrivate::get(asQQmlContext());
 }
 
-void QQmlContextData::initFromTypeCompilationUnit(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &unit, int subComponentIndex)
+void QQmlContextData::initFromTypeCompilationUnit(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &unit, int subComponentIndex)
 {
     typeCompilationUnit = unit;
     componentObjectIndex = subComponentIndex == -1 ? /*root object*/0 : subComponentIndex;
diff --git a/src/qml/qml/qqmlcontext_p.h b/src/qml/qml/qqmlcontext_p.h
index 7e3cef8e1d..1ddd04c9ff 100644
--- a/src/qml/qml/qqmlcontext_p.h
+++ b/src/qml/qml/qqmlcontext_p.h
@@ -66,7 +66,7 @@
 #include <private/qflagpointer_p.h>
 #include <private/qqmlguard_p.h>
 
-#include <private/qv4compileddata_p.h>
+#include <private/qv4executablecompilationunit_p.h>
 #include <private/qv4identifier_p.h>
 
 QT_BEGIN_NAMESPACE
@@ -152,12 +152,12 @@ public:
     QQmlIncubatorPrivate *incubator;
 
     // Compilation unit for contexts that belong to a compiled type.
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> typeCompilationUnit;
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> typeCompilationUnit;
 
     // object index in CompiledData::Unit to component that created this context
     int componentObjectIndex;
 
-    void initFromTypeCompilationUnit(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &unit, int subComponentIndex);
+    void initFromTypeCompilationUnit(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &unit, int subComponentIndex);
 
     // flag indicates whether the context owns the cache (after mutation) or not.
     mutable QV4::IdentifierHash propertyNameCache;
diff --git a/src/qml/qml/qqmlcustomparser_p.h b/src/qml/qml/qqmlcustomparser_p.h
index aa933553a8..c8e1300a1b 100644
--- a/src/qml/qml/qqmlcustomparser_p.h
+++ b/src/qml/qml/qqmlcustomparser_p.h
@@ -80,8 +80,8 @@ public:
     void clearErrors();
     Flags flags() const { return m_flags; }
 
-    virtual void verifyBindings(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &) = 0;
-    virtual void applyBindings(QObject *, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &) = 0;
+    virtual void verifyBindings(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &) = 0;
+    virtual void applyBindings(QObject *, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &) = 0;
 
     QVector<QQmlCompileError> errors() const { return exceptions; }
 
diff --git a/src/qml/qml/qqmldata_p.h b/src/qml/qml/qqmldata_p.h
index f4c03fc17c..299476f5c8 100644
--- a/src/qml/qml/qqmldata_p.h
+++ b/src/qml/qml/qqmldata_p.h
@@ -76,8 +76,8 @@ class QQmlDataExtended;
 class QQmlNotifierEndpoint;
 
 namespace QV4 {
+class ExecutableCompilationUnit;
 namespace CompiledData {
-struct CompilationUnit;
 struct Binding;
 }
 }
@@ -226,14 +226,14 @@ public:
         ~DeferredData();
         unsigned int deferredIdx;
         QMultiHash<int, const QV4::CompiledData::Binding *> bindings;
-        QQmlRefPointer<QV4::CompiledData::CompilationUnit> compilationUnit;//Not always the same as the other compilation unit
+        QQmlRefPointer<QV4::ExecutableCompilationUnit> compilationUnit;//Not always the same as the other compilation unit
         QQmlContextData *context;//Could be either context or outerContext
         Q_DISABLE_COPY(DeferredData);
     };
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> compilationUnit;
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> compilationUnit;
     QVector<DeferredData *> deferredData;
 
-    void deferData(int objectIndex, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &, QQmlContextData *);
+    void deferData(int objectIndex, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &, QQmlContextData *);
     void releaseDeferredData();
 
     QV4::WeakValue jsWrapper;
diff --git a/src/qml/qml/qqmlengine.cpp b/src/qml/qml/qqmlengine.cpp
index bb2b3e462c..f977934b3e 100644
--- a/src/qml/qml/qqmlengine.cpp
+++ b/src/qml/qml/qqmlengine.cpp
@@ -87,9 +87,6 @@
 #include <private/qqmltimer_p.h>
 #endif
 #include <private/qqmlplatform_p.h>
-#if QT_CONFIG(qml_worker_script)
-#include <private/qquickworkerscript_p.h>
-#endif
 #include <private/qqmlloggingcategory_p.h>
 
 #ifdef Q_OS_WIN // for %APPDATA%
@@ -207,6 +204,7 @@ void QQmlEnginePrivate::defineModule()
     qmlRegisterType<QObject>(uri, 2, 0, "QtObject");
     qmlRegisterType<QQmlBind>(uri, 2, 0, "Binding");
     qmlRegisterType<QQmlBind, 8>(uri, 2, 8, "Binding"); // Only available in >= 2.8
+    qmlRegisterType<QQmlBind, 14>(uri, 2, 14, "Binding");
     qmlRegisterCustomType<QQmlConnections>(uri, 2, 0, "Connections", new QQmlConnectionsParser);
     qmlRegisterCustomType<QQmlConnections, 1>(uri, 2, 3, "Connections", new QQmlConnectionsParser); // Only available in QtQml >= 2.3
 #if QT_CONFIG(qml_animation)
@@ -239,9 +237,6 @@ void QQmlEnginePrivate::registerQuickTypes()
 #endif
     qmlRegisterType<QQmlLoggingCategory>(uri, 2, 8, "LoggingCategory");
     qmlRegisterType<QQmlLoggingCategory, 1>(uri, 2, 12, "LoggingCategory");
-#if QT_CONFIG(qml_worker_script)
-    qmlRegisterType<QQuickWorkerScript>(uri, 2, 0, "WorkerScript");
-#endif
 #if QT_CONFIG(qml_locale)
     qmlRegisterUncreatableType<QQmlLocale>(uri, 2, 0, "Locale", QQmlEngine::tr("Locale cannot be instantiated. Use Qt.locale()"));
 #endif
@@ -950,7 +945,11 @@ void QQmlEnginePrivate::init()
     Q_Q(QQmlEngine);
 
     if (baseModulesUninitialized) {
-        qmlRegisterType<QQmlComponent>("QML", 1, 0, "Component"); // required for the Compiler.
+
+        // required for the Compiler.
+        qmlRegisterType<QObject>("QML", 1, 0, "QtObject");
+        qmlRegisterType<QQmlComponent>("QML", 1, 0, "Component");
+
         QQmlData::init();
         baseModulesUninitialized = false;
     }
@@ -963,21 +962,11 @@ void QQmlEnginePrivate::init()
     qRegisterMetaType<QList<int> >();
     qRegisterMetaType<QQmlBinding*>();
 
-    v8engine()->setEngine(q);
+    q->handle()->setQmlEngine(q);
 
     rootContext = new QQmlContext(q,true);
 }
 
-#if QT_CONFIG(qml_worker_script)
-QQuickWorkerScriptEngine *QQmlEnginePrivate::getWorkerScriptEngine()
-{
-    Q_Q(QQmlEngine);
-    if (!workerScriptEngine)
-        workerScriptEngine = new QQuickWorkerScriptEngine(q);
-    return workerScriptEngine;
-}
-#endif
-
 /*!
   \class QQmlEngine
   \since 5.0
@@ -1782,7 +1771,7 @@ void QQmlData::NotifyList::layout()
     todo = nullptr;
 }
 
-void QQmlData::deferData(int objectIndex, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, QQmlContextData *context)
+void QQmlData::deferData(int objectIndex, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, QQmlContextData *context)
 {
     QQmlData::DeferredData *deferData = new QQmlData::DeferredData;
     deferData->deferredIdx = objectIndex;
@@ -2419,7 +2408,7 @@ QQmlPropertyCache *QQmlEnginePrivate::rawPropertyCacheForType(int t, int minorVe
     }
 }
 
-void QQmlEnginePrivate::registerInternalCompositeType(QV4::CompiledData::CompilationUnit *compilationUnit)
+void QQmlEnginePrivate::registerInternalCompositeType(QV4::ExecutableCompilationUnit *compilationUnit)
 {
     compilationUnit->isRegisteredWithEngine = true;
 
@@ -2429,7 +2418,7 @@ void QQmlEnginePrivate::registerInternalCompositeType(QV4::CompiledData::Compila
     m_compositeTypes.insert(compilationUnit->metaTypeId, compilationUnit);
 }
 
-void QQmlEnginePrivate::unregisterInternalCompositeType(QV4::CompiledData::CompilationUnit *compilationUnit)
+void QQmlEnginePrivate::unregisterInternalCompositeType(QV4::ExecutableCompilationUnit *compilationUnit)
 {
     compilationUnit->isRegisteredWithEngine = false;
 
diff --git a/src/qml/qml/qqmlengine_p.h b/src/qml/qml/qqmlengine_p.h
index 4f7fb79593..3b716683fd 100644
--- a/src/qml/qml/qqmlengine_p.h
+++ b/src/qml/qml/qqmlengine_p.h
@@ -76,7 +76,6 @@
 
 #include <private/qobject_p.h>
 
-#include <private/qv8engine_p.h>
 #include <private/qjsengine_p.h>
 #include <private/qqmldirparser_p.h>
 
@@ -94,7 +93,6 @@ class QQmlTypeNameCache;
 class QQmlComponentAttached;
 class QQmlCleanup;
 class QQmlDelayedError;
-class QQuickWorkerScriptEngine;
 class QQmlObjectCreator;
 class QDir;
 class QQmlIncubator;
@@ -150,12 +148,10 @@ public:
     QQmlDelayedError *erroredBindings;
     int inProgressCreations;
 
-    QV8Engine *v8engine() const { return q_func()->handle()->v8Engine; }
     QV4::ExecutionEngine *v4engine() const { return q_func()->handle(); }
 
 #if QT_CONFIG(qml_worker_script)
-    QQuickWorkerScriptEngine *getWorkerScriptEngine();
-    QQuickWorkerScriptEngine *workerScriptEngine;
+    QThread *workerScriptEngine;
 #endif
 
     QUrl baseUrl;
@@ -223,8 +219,8 @@ public:
     QQmlMetaObject metaObjectForType(int) const;
     QQmlPropertyCache *propertyCacheForType(int);
     QQmlPropertyCache *rawPropertyCacheForType(int, int minorVersion = -1);
-    void registerInternalCompositeType(QV4::CompiledData::CompilationUnit *compilationUnit);
-    void unregisterInternalCompositeType(QV4::CompiledData::CompilationUnit *compilationUnit);
+    void registerInternalCompositeType(QV4::ExecutableCompilationUnit *compilationUnit);
+    void unregisterInternalCompositeType(QV4::ExecutableCompilationUnit *compilationUnit);
 
     bool isTypeLoaded(const QUrl &url) const;
     bool isScriptLoaded(const QUrl &url) const;
@@ -242,7 +238,6 @@ public:
     static void warning(QQmlEnginePrivate *, const QQmlError &);
     static void warning(QQmlEnginePrivate *, const QList<QQmlError> &);
 
-    inline static QV8Engine *getV8Engine(QQmlEngine *e);
     inline static QV4::ExecutionEngine *getV4Engine(QQmlEngine *e);
     inline static QQmlEnginePrivate *get(QQmlEngine *e);
     inline static const QQmlEnginePrivate *get(const QQmlEngine *e);
@@ -270,7 +265,7 @@ private:
 
     // These members must be protected by a QQmlEnginePrivate::Locker as they are required by
     // the threaded loader.  Only access them through their respective accessor methods.
-    QHash<int, QV4::CompiledData::CompilationUnit *> m_compositeTypes;
+    QHash<int, QV4::ExecutableCompilationUnit *> m_compositeTypes;
     static bool s_designerMode;
 
     // These members is protected by the full QQmlEnginePrivate::mutex mutex
@@ -316,8 +311,8 @@ Returns true if the calling thread is the QQmlEngine thread.
 */
 bool QQmlEnginePrivate::isEngineThread() const
 {
-    Q_Q(const QQmlEngine);
-    return QThread::currentThread() == q->thread();
+
+    return QThread::currentThread() == q_ptr->thread();
 }
 
 /*!
@@ -342,8 +337,6 @@ the instance directly if not.
 template<typename T>
 void QQmlEnginePrivate::deleteInEngineThread(T *value)
 {
-    Q_Q(QQmlEngine);
-
     Q_ASSERT(value);
     if (isEngineThread()) {
         delete value;
@@ -359,7 +352,7 @@ void QQmlEnginePrivate::deleteInEngineThread(T *value)
         toDeleteInEngineThread.append(i);
         mutex.unlock();
         if (wasEmpty)
-            QCoreApplication::postEvent(q, new QEvent(QEvent::User));
+            QCoreApplication::postEvent(q_ptr, new QEvent(QEvent::User));
     }
 }
 
@@ -390,13 +383,6 @@ QQmlPropertyCache *QQmlEnginePrivate::cache(const QQmlType &type, int minorVersi
     return QQmlMetaType::propertyCache(type, minorVersion);
 }
 
-QV8Engine *QQmlEnginePrivate::getV8Engine(QQmlEngine *e)
-{
-    Q_ASSERT(e);
-
-    return e->handle()->v8Engine;
-}
-
 QV4::ExecutionEngine *QQmlEnginePrivate::getV4Engine(QQmlEngine *e)
 {
     Q_ASSERT(e);
diff --git a/src/qml/qml/qqmlglobal_p.h b/src/qml/qml/qqmlglobal_p.h
index 53caffe040..136159993a 100644
--- a/src/qml/qml/qqmlglobal_p.h
+++ b/src/qml/qml/qqmlglobal_p.h
@@ -55,7 +55,6 @@
 #include <QtCore/QObject>
 #include <private/qqmlmetaobject_p.h>
 #include <private/qmetaobject_p.h>
-#include <private/qv8engine_p.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/qml/qml/qqmlincubator_p.h b/src/qml/qml/qqmlincubator_p.h
index 676ba1a29a..57ec8249cb 100644
--- a/src/qml/qml/qqmlincubator_p.h
+++ b/src/qml/qml/qqmlincubator_p.h
@@ -87,7 +87,7 @@ public:
     QPointer<QObject> result;
     QQmlGuardedContextData rootContext;
     QQmlEnginePrivate *enginePriv;
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> compilationUnit;
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> compilationUnit;
     QScopedPointer<QQmlObjectCreator> creator;
     int subComponentToCreate;
     QQmlVMEGuard vmeGuard;
diff --git a/src/qml/qml/qqmljavascriptexpression.cpp b/src/qml/qml/qqmljavascriptexpression.cpp
index 9a3a5218e0..e799267769 100644
--- a/src/qml/qml/qqmljavascriptexpression.cpp
+++ b/src/qml/qml/qqmljavascriptexpression.cpp
@@ -392,10 +392,10 @@ void QQmlJavaScriptExpression::setupFunction(QV4::ExecutionContext *qmlContext,
         return;
     m_qmlScope.set(qmlContext->engine(), *qmlContext);
     m_v4Function = f;
-    setCompilationUnit(m_v4Function->compilationUnit);
+    setCompilationUnit(m_v4Function->executableCompilationUnit());
 }
 
-void QQmlJavaScriptExpression::setCompilationUnit(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit)
+void QQmlJavaScriptExpression::setCompilationUnit(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit)
 {
     m_compilationUnit = compilationUnit;
 }
diff --git a/src/qml/qml/qqmljavascriptexpression_p.h b/src/qml/qml/qqmljavascriptexpression_p.h
index 92f2ccbb4a..eecee08062 100644
--- a/src/qml/qml/qqmljavascriptexpression_p.h
+++ b/src/qml/qml/qqmljavascriptexpression_p.h
@@ -153,7 +153,7 @@ protected:
     void createQmlBinding(QQmlContextData *ctxt, QObject *scope, const QString &code, const QString &filename, quint16 line);
 
     void setupFunction(QV4::ExecutionContext *qmlContext, QV4::Function *f);
-    void setCompilationUnit(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit);
+    void setCompilationUnit(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit);
 
     // We store some flag bits in the following flag pointers.
     //    activeGuards:flag1  - notifyOnValueChanged
@@ -178,7 +178,7 @@ private:
     QQmlJavaScriptExpression  *m_nextExpression;
 
     QV4::PersistentValue m_qmlScope;
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> m_compilationUnit;
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> m_compilationUnit;
     QV4::Function *m_v4Function;
 };
 
diff --git a/src/qml/qml/qqmllocale.cpp b/src/qml/qml/qqmllocale.cpp
index 2b17037df0..dca13ac8d4 100644
--- a/src/qml/qml/qqmllocale.cpp
+++ b/src/qml/qml/qqmllocale.cpp
@@ -662,7 +662,7 @@ LOCALE_STRING_PROPERTY(exponential)
 LOCALE_STRING_PROPERTY(amText)
 LOCALE_STRING_PROPERTY(pmText)
 
-class QV4LocaleDataDeletable : public QV8Engine::Deletable
+class QV4LocaleDataDeletable : public QV4::ExecutionEngine::Deletable
 {
 public:
     QV4LocaleDataDeletable(QV4::ExecutionEngine *engine);
diff --git a/src/qml/qml/qqmlmetatype.cpp b/src/qml/qml/qqmlmetatype.cpp
index 09df23de51..a5b92d14f7 100644
--- a/src/qml/qml/qqmlmetatype.cpp
+++ b/src/qml/qml/qqmlmetatype.cpp
@@ -499,7 +499,7 @@ QQmlType QQmlMetaType::registerCompositeType(const QQmlPrivate::RegisterComposit
     return QQmlType(priv);
 }
 
-void QQmlMetaType::registerInternalCompositeType(QV4::CompiledData::CompilationUnit *compilationUnit)
+void QQmlMetaType::registerInternalCompositeType(QV4::ExecutableCompilationUnit *compilationUnit)
 {
     QByteArray name = compilationUnit->rootPropertyCache()->className();
 
@@ -526,7 +526,7 @@ void QQmlMetaType::registerInternalCompositeType(QV4::CompiledData::CompilationU
     data->qmlLists.insert(lst_type, ptr_type);
 }
 
-void QQmlMetaType::unregisterInternalCompositeType(QV4::CompiledData::CompilationUnit *compilationUnit)
+void QQmlMetaType::unregisterInternalCompositeType(QV4::ExecutableCompilationUnit *compilationUnit)
 {
     int ptr_type = compilationUnit->metaTypeId;
     int lst_type = compilationUnit->listMetaTypeId;
diff --git a/src/qml/qml/qqmlmetatype_p.h b/src/qml/qml/qqmlmetatype_p.h
index 9af982d1c3..911e519cf2 100644
--- a/src/qml/qml/qqmlmetatype_p.h
+++ b/src/qml/qml/qqmlmetatype_p.h
@@ -61,6 +61,8 @@ class QQmlTypeModule;
 class QMutex;
 class QQmlError;
 
+namespace QV4 { class ExecutableCompilationUnit; }
+
 class Q_QML_PRIVATE_EXPORT QQmlMetaType
 {
 public:
@@ -78,8 +80,8 @@ public:
 
     static void unregisterType(int type);
 
-    static void registerInternalCompositeType(QV4::CompiledData::CompilationUnit *compilationUnit);
-    static void unregisterInternalCompositeType(QV4::CompiledData::CompilationUnit *compilationUnit);
+    static void registerInternalCompositeType(QV4::ExecutableCompilationUnit *compilationUnit);
+    static void unregisterInternalCompositeType(QV4::ExecutableCompilationUnit *compilationUnit);
 
     static void registerModule(const char *uri, int versionMajor, int versionMinor);
     static bool protectModule(const char *uri, int majVersion);
diff --git a/src/qml/qml/qqmlobjectcreator.cpp b/src/qml/qml/qqmlobjectcreator.cpp
index 26d3b5b6c1..e5f376fd34 100644
--- a/src/qml/qml/qqmlobjectcreator.cpp
+++ b/src/qml/qml/qqmlobjectcreator.cpp
@@ -57,6 +57,8 @@
 #include <private/qqmldebugserviceinterfaces_p.h>
 #include <private/qjsvalue_p.h>
 
+#include <qtqml_tracepoints_p.h>
+
 QT_USE_NAMESPACE
 
 namespace {
@@ -71,7 +73,7 @@ struct ActiveOCRestorer
 };
 }
 
-QQmlObjectCreator::QQmlObjectCreator(QQmlContextData *parentContext, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, QQmlContextData *creationContext,
+QQmlObjectCreator::QQmlObjectCreator(QQmlContextData *parentContext, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, QQmlContextData *creationContext,
                                      QQmlIncubatorPrivate *incubator)
     : phase(Startup)
     , compilationUnit(compilationUnit)
@@ -98,7 +100,7 @@ QQmlObjectCreator::QQmlObjectCreator(QQmlContextData *parentContext, const QQmlR
     }
 }
 
-QQmlObjectCreator::QQmlObjectCreator(QQmlContextData *parentContext, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, QQmlObjectCreatorSharedState *inheritedSharedState)
+QQmlObjectCreator::QQmlObjectCreator(QQmlContextData *parentContext, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, QQmlObjectCreatorSharedState *inheritedSharedState)
     : phase(Startup)
     , compilationUnit(compilationUnit)
     , propertyCaches(&compilationUnit->propertyCaches)
@@ -371,7 +373,7 @@ void QQmlObjectCreator::setPropertyValue(const QQmlPropertyData *property, const
             propertyType = QMetaType::Int;
         } else {
             // ### This should be resolved earlier at compile time and the binding value should be changed accordingly.
-            QVariant value = binding->valueAsString(compilationUnit.data());
+            QVariant value = compilationUnit->bindingValueAsString(binding);
             bool ok = QQmlPropertyPrivate::write(_qobject, *property, value, context);
             Q_ASSERT(ok);
             Q_UNUSED(ok);
@@ -404,7 +406,7 @@ void QQmlObjectCreator::setPropertyValue(const QQmlPropertyData *property, const
     switch (propertyType) {
     case QMetaType::QVariant: {
         if (binding->type == QV4::CompiledData::Binding::Type_Number) {
-            double n = binding->valueAsNumber(compilationUnit->constants);
+            double n = compilationUnit->bindingValueAsNumber(binding);
             if (double(int(n)) == n) {
                 if (property->isVarProperty()) {
                     _vmeMetaObject->setVMEProperty(property->coreIndex(), QV4::Value::fromInt32(int(n)));
@@ -436,7 +438,7 @@ void QQmlObjectCreator::setPropertyValue(const QQmlPropertyData *property, const
                 property->writeProperty(_qobject, &nullValue, propertyWriteFlags);
             }
         } else {
-            QString stringValue = binding->valueAsString(compilationUnit.data());
+            QString stringValue = compilationUnit->bindingValueAsString(binding);
             if (property->isVarProperty()) {
                 QV4::ScopedString s(scope, v4->newString(stringValue));
                 _vmeMetaObject->setVMEProperty(property->coreIndex(), s);
@@ -449,25 +451,25 @@ void QQmlObjectCreator::setPropertyValue(const QQmlPropertyData *property, const
     break;
     case QVariant::String: {
         assertOrNull(binding->evaluatesToString());
-        QString value = binding->valueAsString(compilationUnit.data());
+        QString value = compilationUnit->bindingValueAsString(binding);
         property->writeProperty(_qobject, &value, propertyWriteFlags);
     }
     break;
     case QVariant::StringList: {
         assertOrNull(binding->evaluatesToString());
-        QStringList value(binding->valueAsString(compilationUnit.data()));
+        QStringList value(compilationUnit->bindingValueAsString(binding));
         property->writeProperty(_qobject, &value, propertyWriteFlags);
     }
     break;
     case QVariant::ByteArray: {
         assertType(QV4::CompiledData::Binding::Type_String);
-        QByteArray value(binding->valueAsString(compilationUnit.data()).toUtf8());
+        QByteArray value(compilationUnit->bindingValueAsString(binding).toUtf8());
         property->writeProperty(_qobject, &value, propertyWriteFlags);
     }
     break;
     case QVariant::Url: {
         assertType(QV4::CompiledData::Binding::Type_String);
-        QString string = binding->valueAsString(compilationUnit.data());
+        QString string = compilationUnit->bindingValueAsString(binding);
         // Encoded dir-separators defeat QUrl processing - decode them first
         string.replace(QLatin1String("%2f"), QLatin1String("/"), Qt::CaseInsensitive);
         QUrl value = string.isEmpty() ? QUrl() : compilationUnit->finalUrl().resolved(QUrl(string));
@@ -479,7 +481,7 @@ void QQmlObjectCreator::setPropertyValue(const QQmlPropertyData *property, const
     break;
     case QVariant::UInt: {
         assertType(QV4::CompiledData::Binding::Type_Number);
-        double d = binding->valueAsNumber(compilationUnit->constants);
+        double d = compilationUnit->bindingValueAsNumber(binding);
         uint value = uint(d);
         property->writeProperty(_qobject, &value, propertyWriteFlags);
         break;
@@ -487,7 +489,7 @@ void QQmlObjectCreator::setPropertyValue(const QQmlPropertyData *property, const
     break;
     case QVariant::Int: {
         assertType(QV4::CompiledData::Binding::Type_Number);
-        double d = binding->valueAsNumber(compilationUnit->constants);
+        double d = compilationUnit->bindingValueAsNumber(binding);
         int value = int(d);
         property->writeProperty(_qobject, &value, propertyWriteFlags);
         break;
@@ -495,19 +497,19 @@ void QQmlObjectCreator::setPropertyValue(const QQmlPropertyData *property, const
     break;
     case QMetaType::Float: {
         assertType(QV4::CompiledData::Binding::Type_Number);
-        float value = float(binding->valueAsNumber(compilationUnit->constants));
+        float value = float(compilationUnit->bindingValueAsNumber(binding));
         property->writeProperty(_qobject, &value, propertyWriteFlags);
     }
     break;
     case QVariant::Double: {
         assertType(QV4::CompiledData::Binding::Type_Number);
-        double value = binding->valueAsNumber(compilationUnit->constants);
+        double value = compilationUnit->bindingValueAsNumber(binding);
         property->writeProperty(_qobject, &value, propertyWriteFlags);
     }
     break;
     case QVariant::Color: {
         bool ok = false;
-        uint colorValue = QQmlStringConverters::rgbaFromString(binding->valueAsString(compilationUnit.data()), &ok);
+        uint colorValue = QQmlStringConverters::rgbaFromString(compilationUnit->bindingValueAsString(binding), &ok);
         assertOrNull(ok);
         struct { void *data[4]; } buffer;
         if (QQml_valueTypeProvider()->storeValueType(property->propType(), &colorValue, &buffer, sizeof(buffer))) {
@@ -518,21 +520,21 @@ void QQmlObjectCreator::setPropertyValue(const QQmlPropertyData *property, const
 #if QT_CONFIG(datestring)
     case QVariant::Date: {
         bool ok = false;
-        QDate value = QQmlStringConverters::dateFromString(binding->valueAsString(compilationUnit.data()), &ok);
+        QDate value = QQmlStringConverters::dateFromString(compilationUnit->bindingValueAsString(binding), &ok);
         assertOrNull(ok);
         property->writeProperty(_qobject, &value, propertyWriteFlags);
     }
     break;
     case QVariant::Time: {
         bool ok = false;
-        QTime value = QQmlStringConverters::timeFromString(binding->valueAsString(compilationUnit.data()), &ok);
+        QTime value = QQmlStringConverters::timeFromString(compilationUnit->bindingValueAsString(binding), &ok);
         assertOrNull(ok);
         property->writeProperty(_qobject, &value, propertyWriteFlags);
     }
     break;
     case QVariant::DateTime: {
         bool ok = false;
-        QDateTime value = QQmlStringConverters::dateTimeFromString(binding->valueAsString(compilationUnit.data()), &ok);
+        QDateTime value = QQmlStringConverters::dateTimeFromString(compilationUnit->bindingValueAsString(binding), &ok);
         // ### VME compatibility :(
         {
             const qint64 date = value.date().toJulianDay();
@@ -546,42 +548,42 @@ void QQmlObjectCreator::setPropertyValue(const QQmlPropertyData *property, const
 #endif // datestring
     case QVariant::Point: {
         bool ok = false;
-        QPoint value = QQmlStringConverters::pointFFromString(binding->valueAsString(compilationUnit.data()), &ok).toPoint();
+        QPoint value = QQmlStringConverters::pointFFromString(compilationUnit->bindingValueAsString(binding), &ok).toPoint();
         assertOrNull(ok);
         property->writeProperty(_qobject, &value, propertyWriteFlags);
     }
     break;
     case QVariant::PointF: {
         bool ok = false;
-        QPointF value = QQmlStringConverters::pointFFromString(binding->valueAsString(compilationUnit.data()), &ok);
+        QPointF value = QQmlStringConverters::pointFFromString(compilationUnit->bindingValueAsString(binding), &ok);
         assertOrNull(ok);
         property->writeProperty(_qobject, &value, propertyWriteFlags);
     }
     break;
     case QVariant::Size: {
         bool ok = false;
-        QSize value = QQmlStringConverters::sizeFFromString(binding->valueAsString(compilationUnit.data()), &ok).toSize();
+        QSize value = QQmlStringConverters::sizeFFromString(compilationUnit->bindingValueAsString(binding), &ok).toSize();
         assertOrNull(ok);
         property->writeProperty(_qobject, &value, propertyWriteFlags);
     }
     break;
     case QVariant::SizeF: {
         bool ok = false;
-        QSizeF value = QQmlStringConverters::sizeFFromString(binding->valueAsString(compilationUnit.data()), &ok);
+        QSizeF value = QQmlStringConverters::sizeFFromString(compilationUnit->bindingValueAsString(binding), &ok);
         assertOrNull(ok);
         property->writeProperty(_qobject, &value, propertyWriteFlags);
     }
     break;
     case QVariant::Rect: {
         bool ok = false;
-        QRect value = QQmlStringConverters::rectFFromString(binding->valueAsString(compilationUnit.data()), &ok).toRect();
+        QRect value = QQmlStringConverters::rectFFromString(compilationUnit->bindingValueAsString(binding), &ok).toRect();
         assertOrNull(ok);
         property->writeProperty(_qobject, &value, propertyWriteFlags);
     }
     break;
     case QVariant::RectF: {
         bool ok = false;
-        QRectF value = QQmlStringConverters::rectFFromString(binding->valueAsString(compilationUnit.data()), &ok);
+        QRectF value = QQmlStringConverters::rectFFromString(compilationUnit->bindingValueAsString(binding), &ok);
         assertOrNull(ok);
         property->writeProperty(_qobject, &value, propertyWriteFlags);
     }
@@ -597,7 +599,7 @@ void QQmlObjectCreator::setPropertyValue(const QQmlPropertyData *property, const
             float xp;
             float yp;
         } vec;
-        bool ok = QQmlStringConverters::createFromString(QMetaType::QVector2D, binding->valueAsString(compilationUnit.data()), &vec, sizeof(vec));
+        bool ok = QQmlStringConverters::createFromString(QMetaType::QVector2D, compilationUnit->bindingValueAsString(binding), &vec, sizeof(vec));
         assertOrNull(ok);
         Q_UNUSED(ok);
         property->writeProperty(_qobject, &vec, propertyWriteFlags);
@@ -609,7 +611,7 @@ void QQmlObjectCreator::setPropertyValue(const QQmlPropertyData *property, const
             float yp;
             float zy;
         } vec;
-        bool ok = QQmlStringConverters::createFromString(QMetaType::QVector3D, binding->valueAsString(compilationUnit.data()), &vec, sizeof(vec));
+        bool ok = QQmlStringConverters::createFromString(QMetaType::QVector3D, compilationUnit->bindingValueAsString(binding), &vec, sizeof(vec));
         assertOrNull(ok);
         Q_UNUSED(ok);
         property->writeProperty(_qobject, &vec, propertyWriteFlags);
@@ -622,7 +624,7 @@ void QQmlObjectCreator::setPropertyValue(const QQmlPropertyData *property, const
             float zy;
             float wp;
         } vec;
-        bool ok = QQmlStringConverters::createFromString(QMetaType::QVector4D, binding->valueAsString(compilationUnit.data()), &vec, sizeof(vec));
+        bool ok = QQmlStringConverters::createFromString(QMetaType::QVector4D, compilationUnit->bindingValueAsString(binding), &vec, sizeof(vec));
         assertOrNull(ok);
         Q_UNUSED(ok);
         property->writeProperty(_qobject, &vec, propertyWriteFlags);
@@ -635,7 +637,7 @@ void QQmlObjectCreator::setPropertyValue(const QQmlPropertyData *property, const
             float yp;
             float zp;
         } vec;
-        bool ok = QQmlStringConverters::createFromString(QMetaType::QQuaternion, binding->valueAsString(compilationUnit.data()), &vec, sizeof(vec));
+        bool ok = QQmlStringConverters::createFromString(QMetaType::QQuaternion, compilationUnit->bindingValueAsString(binding), &vec, sizeof(vec));
         assertOrNull(ok);
         Q_UNUSED(ok);
         property->writeProperty(_qobject, &vec, propertyWriteFlags);
@@ -649,12 +651,12 @@ void QQmlObjectCreator::setPropertyValue(const QQmlPropertyData *property, const
         if (property->propType() == qMetaTypeId<QList<qreal> >()) {
             assertType(QV4::CompiledData::Binding::Type_Number);
             QList<qreal> value;
-            value.append(binding->valueAsNumber(compilationUnit->constants));
+            value.append(compilationUnit->bindingValueAsNumber(binding));
             property->writeProperty(_qobject, &value, propertyWriteFlags);
             break;
         } else if (property->propType() == qMetaTypeId<QList<int> >()) {
             assertType(QV4::CompiledData::Binding::Type_Number);
-            double n = binding->valueAsNumber(compilationUnit->constants);
+            double n = compilationUnit->bindingValueAsNumber(binding);
             QList<int> value;
             value.append(int(n));
             property->writeProperty(_qobject, &value, propertyWriteFlags);
@@ -667,7 +669,7 @@ void QQmlObjectCreator::setPropertyValue(const QQmlPropertyData *property, const
             break;
         } else if (property->propType() == qMetaTypeId<QList<QUrl> >()) {
             assertType(QV4::CompiledData::Binding::Type_String);
-            QString urlString = binding->valueAsString(compilationUnit.data());
+            QString urlString = compilationUnit->bindingValueAsString(binding);
             QUrl u = urlString.isEmpty() ? QUrl()
                                          : compilationUnit->finalUrl().resolved(QUrl(urlString));
             QList<QUrl> value;
@@ -677,7 +679,7 @@ void QQmlObjectCreator::setPropertyValue(const QQmlPropertyData *property, const
         } else if (property->propType() == qMetaTypeId<QList<QString> >()) {
             assertOrNull(binding->evaluatesToString());
             QList<QString> value;
-            value.append(binding->valueAsString(compilationUnit.data()));
+            value.append(compilationUnit->bindingValueAsString(binding));
             property->writeProperty(_qobject, &value, propertyWriteFlags);
             break;
         } else if (property->propType() == qMetaTypeId<QJSValue>()) {
@@ -685,7 +687,7 @@ void QQmlObjectCreator::setPropertyValue(const QQmlPropertyData *property, const
             if (binding->type == QV4::CompiledData::Binding::Type_Boolean) {
                 value = QJSValue(binding->valueAsBoolean());
             } else if (binding->type == QV4::CompiledData::Binding::Type_Number) {
-                double n = binding->valueAsNumber(compilationUnit->constants);
+                double n = compilationUnit->bindingValueAsNumber(binding);
                 if (double(int(n)) == n) {
                     value = QJSValue(int(n));
                 } else
@@ -693,14 +695,14 @@ void QQmlObjectCreator::setPropertyValue(const QQmlPropertyData *property, const
             } else if (binding->type == QV4::CompiledData::Binding::Type_Null) {
                 value = QJSValue::NullValue;
             } else {
-                value = QJSValue(binding->valueAsString(compilationUnit.data()));
+                value = QJSValue(compilationUnit->bindingValueAsString(binding));
             }
             property->writeProperty(_qobject, &value, propertyWriteFlags);
             break;
         }
 
         // otherwise, try a custom type assignment
-        QString stringValue = binding->valueAsString(compilationUnit.data());
+        QString stringValue = compilationUnit->bindingValueAsString(binding);
         QQmlMetaType::StringConverter converter = QQmlMetaType::customStringConverter(property->propType());
         Q_ASSERT(converter);
         QVariant value = (*converter)(stringValue);
@@ -814,7 +816,7 @@ bool QQmlObjectCreator::setPropertyBinding(const QQmlPropertyData *bindingProper
 {
     if (binding->type == QV4::CompiledData::Binding::Type_AttachedProperty) {
         Q_ASSERT(stringAt(compilationUnit->objectAt(binding->value.objectIndex)->inheritedTypeNameIndex).isEmpty());
-        QV4::CompiledData::ResolvedTypeReference *tr = resolvedType(binding->propertyNameIndex);
+        QV4::ResolvedTypeReference *tr = resolvedType(binding->propertyNameIndex);
         Q_ASSERT(tr);
         QQmlType attachedType = tr->type;
         if (!attachedType.isValid()) {
@@ -833,13 +835,14 @@ bool QQmlObjectCreator::setPropertyBinding(const QQmlPropertyData *bindingProper
 
     // ### resolve this at compile time
     if (bindingProperty && bindingProperty->propType() == qMetaTypeId<QQmlScriptString>()) {
-        QQmlScriptString ss(binding->valueAsScriptString(compilationUnit.data()), context->asQQmlContext(), _scopeObject);
+        QQmlScriptString ss(compilationUnit->bindingValueAsScriptString(binding),
+                            context->asQQmlContext(), _scopeObject);
         ss.d.data()->bindingId = binding->type == QV4::CompiledData::Binding::Type_Script ? binding->value.compiledScriptIndex : (quint32)QQmlBinding::Invalid;
         ss.d.data()->lineNumber = binding->location.line;
         ss.d.data()->columnNumber = binding->location.column;
         ss.d.data()->isStringLiteral = binding->type == QV4::CompiledData::Binding::Type_String;
         ss.d.data()->isNumberLiteral = binding->type == QV4::CompiledData::Binding::Type_Number;
-        ss.d.data()->numberValue = binding->valueAsNumber(compilationUnit->constants);
+        ss.d.data()->numberValue = compilationUnit->bindingValueAsNumber(binding);
 
         QQmlPropertyData::WriteFlags propertyWriteFlags = QQmlPropertyData::BypassInterceptor |
                                                             QQmlPropertyData::RemoveBindingOnAliasWrite;
@@ -1161,6 +1164,9 @@ QObject *QQmlObjectCreator::createInstance(int index, QObject *parent, bool isCo
 {
     const QV4::CompiledData::Object *obj = compilationUnit->objectAt(index);
     QQmlObjectCreationProfiler profiler(sharedState->profiler.profiler, obj);
+    Q_TRACE(QQmlObjectCreator_createInstance_entry, compilationUnit.data(), obj, context->url());
+    QString typeName;
+    Q_TRACE_EXIT(QQmlObjectCreator_createInstance_exit, typeName);
 
     ActiveOCRestorer ocRestorer(this, QQmlEnginePrivate::get(engine));
 
@@ -1174,20 +1180,17 @@ QObject *QQmlObjectCreator::createInstance(int index, QObject *parent, bool isCo
     if (obj->flags & QV4::CompiledData::Object::IsComponent) {
         isComponent = true;
         QQmlComponent *component = new QQmlComponent(engine, compilationUnit.data(), index, parent);
-        Q_QML_OC_PROFILE(sharedState->profiler, profiler.update(
-                         compilationUnit.data(), obj, QStringLiteral("<component>"), context->url()));
+        typeName = QStringLiteral("<component>");
         QQmlComponentPrivate::get(component)->creationContext = context;
         instance = component;
         ddata = QQmlData::get(instance, /*create*/true);
     } else {
-        QV4::CompiledData::ResolvedTypeReference *typeRef
-                = resolvedType(obj->inheritedTypeNameIndex);
+        QV4::ResolvedTypeReference *typeRef = resolvedType(obj->inheritedTypeNameIndex);
         Q_ASSERT(typeRef);
         installPropertyCache = !typeRef->isFullyDynamicType;
         QQmlType type = typeRef->type;
         if (type.isValid()) {
-            Q_QML_OC_PROFILE(sharedState->profiler, profiler.update(
-                             compilationUnit.data(), obj, type.qmlTypeName(), context->url()));
+            typeName = type.qmlTypeName();
 
             void *ddataMemory = nullptr;
             type.create(&instance, &ddataMemory, sizeof(QQmlData));
@@ -1219,9 +1222,7 @@ QObject *QQmlObjectCreator::createInstance(int index, QObject *parent, bool isCo
             sharedState->allCreatedObjects.push(instance);
         } else {
             Q_ASSERT(typeRef->compilationUnit);
-            Q_QML_OC_PROFILE(sharedState->profiler, profiler.update(
-                             compilationUnit.data(), obj, typeRef->compilationUnit->fileName(),
-                             context->url()));
+            typeName = typeRef->compilationUnit->fileName();
             if (typeRef->compilationUnit->unitData()->isSingleton())
             {
                 recordError(obj->location, tr("Composite Singleton Type %1 is not creatable").arg(stringAt(obj->inheritedTypeNameIndex)));
@@ -1248,6 +1249,11 @@ QObject *QQmlObjectCreator::createInstance(int index, QObject *parent, bool isCo
 
         ddata = QQmlData::get(instance, /*create*/true);
     }
+
+    Q_QML_OC_PROFILE(sharedState->profiler, profiler.update(
+        compilationUnit.data(), obj, typeName, context->url()));
+    Q_UNUSED(typeName); // only relevant for tracing
+
     ddata->lineNumber = obj->location.line;
     ddata->columnNumber = obj->location.column;
 
diff --git a/src/qml/qml/qqmlobjectcreator_p.h b/src/qml/qml/qqmlobjectcreator_p.h
index 5aca60e2f0..0766e2082e 100644
--- a/src/qml/qml/qqmlobjectcreator_p.h
+++ b/src/qml/qml/qqmlobjectcreator_p.h
@@ -85,7 +85,7 @@ class Q_QML_PRIVATE_EXPORT QQmlObjectCreator
 {
     Q_DECLARE_TR_FUNCTIONS(QQmlObjectCreator)
 public:
-    QQmlObjectCreator(QQmlContextData *parentContext, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, QQmlContextData *creationContext, QQmlIncubatorPrivate  *incubator = nullptr);
+    QQmlObjectCreator(QQmlContextData *parentContext, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, QQmlContextData *creationContext, QQmlIncubatorPrivate  *incubator = nullptr);
     ~QQmlObjectCreator();
 
     QObject *create(int subComponentIndex = -1, QObject *parent = nullptr, QQmlInstantiationInterrupt *interrupt = nullptr);
@@ -104,7 +104,7 @@ public:
     QFiniteStack<QPointer<QObject> > &allCreatedObjects() const { return sharedState->allCreatedObjects; }
 
 private:
-    QQmlObjectCreator(QQmlContextData *contextData, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, QQmlObjectCreatorSharedState *inheritedSharedState);
+    QQmlObjectCreator(QQmlContextData *contextData, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, QQmlObjectCreatorSharedState *inheritedSharedState);
 
     void init(QQmlContextData *parentContext);
 
@@ -125,7 +125,7 @@ private:
 
     inline QV4::QmlContext *currentQmlContext();
     Q_NEVER_INLINE void createQmlContext();
-    QV4::CompiledData::ResolvedTypeReference *resolvedType(int id) const
+    QV4::ResolvedTypeReference *resolvedType(int id) const
     {
         return compilationUnit->resolvedType(id);
     }
@@ -141,7 +141,7 @@ private:
 
     QQmlEngine *engine;
     QV4::ExecutionEngine *v4;
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> compilationUnit;
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> compilationUnit;
     const QV4::CompiledData::Unit *qmlUnit;
     QQmlGuardedContextData parentContext;
     QQmlContextData *context;
diff --git a/src/qml/qml/qqmlprivate.h b/src/qml/qml/qqmlprivate.h
index fa05b3fe19..ae84803648 100644
--- a/src/qml/qml/qqmlprivate.h
+++ b/src/qml/qml/qqmlprivate.h
@@ -190,16 +190,13 @@ namespace QQmlPrivate
     template<typename T>
     class AttachedPropertySelector<T, 1>
     {
-        static inline QObject *attachedProperties(QObject *obj) {
-            return T::qmlAttachedProperties(obj);
-        }
         template<typename ReturnType>
         static inline const QMetaObject *attachedPropertiesMetaObject(ReturnType *(*)(QObject *)) {
             return &ReturnType::staticMetaObject;
         }
     public:
         static inline QQmlAttachedPropertiesFunc func() {
-            return &attachedProperties;
+            return QQmlAttachedPropertiesFunc(&T::qmlAttachedProperties);
         }
         static inline const QMetaObject *metaObject() {
             return attachedPropertiesMetaObject(&T::qmlAttachedProperties);
diff --git a/src/qml/qml/qqmlproperty_p.h b/src/qml/qml/qqmlproperty_p.h
index bafcba5971..285c34d7fa 100644
--- a/src/qml/qml/qqmlproperty_p.h
+++ b/src/qml/qml/qqmlproperty_p.h
@@ -59,6 +59,7 @@
 #include <private/qqmlrefcount_p.h>
 #include <private/qqmlcontext_p.h>
 #include <private/qqmlboundsignalexpressionpointer_p.h>
+#include <private/qqmlpropertydata_p.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/qml/qml/qqmlpropertycache.cpp b/src/qml/qml/qqmlpropertycache.cpp
index a6546ae330..48c4216d54 100644
--- a/src/qml/qml/qqmlpropertycache.cpp
+++ b/src/qml/qml/qqmlpropertycache.cpp
@@ -868,7 +868,7 @@ QQmlPropertyCacheMethodArguments *QQmlPropertyCache::createArgumentsObject(int a
 QString QQmlPropertyCache::signalParameterStringForJS(QV4::ExecutionEngine *engine, const QList<QByteArray> &parameterNameList, QString *errorString)
 {
     bool unnamedParameter = false;
-    const QSet<QString> &illegalNames = engine->v8Engine->illegalNames();
+    const QSet<QString> &illegalNames = engine->illegalNames();
     QString parameters;
 
     for (int i = 0; i < parameterNameList.count(); ++i) {
diff --git a/src/qml/qml/qqmltype.cpp b/src/qml/qml/qqmltype.cpp
index 926e2810d5..6b4e0a0734 100644
--- a/src/qml/qml/qqmltype.cpp
+++ b/src/qml/qml/qqmltype.cpp
@@ -178,7 +178,7 @@ QQmlType QQmlType::resolveCompositeBaseType(QQmlEnginePrivate *engine) const
     QQmlRefPointer<QQmlTypeData> td(engine->typeLoader.getType(sourceUrl()));
     if (td.isNull() || !td->isComplete())
         return QQmlType();
-    QV4::CompiledData::CompilationUnit *compilationUnit = td->compilationUnit();
+    QV4::ExecutableCompilationUnit *compilationUnit = td->compilationUnit();
     const QMetaObject *mo = compilationUnit->rootPropertyCache()->firstCppMetaObject();
     return QQmlMetaType::qmlType(mo);
 }
@@ -192,7 +192,7 @@ QQmlPropertyCache *QQmlType::compositePropertyCache(QQmlEnginePrivate *engine) c
     QQmlRefPointer<QQmlTypeData> td(engine->typeLoader.getType(sourceUrl()));
     if (td.isNull() || !td->isComplete())
         return nullptr;
-    QV4::CompiledData::CompilationUnit *compilationUnit = td->compilationUnit();
+    QV4::ExecutableCompilationUnit *compilationUnit = td->compilationUnit();
     return compilationUnit->rootPropertyCache().data();
 }
 
diff --git a/src/qml/qml/qqmltypeloader.cpp b/src/qml/qml/qqmltypeloader.cpp
index 457558fb56..1022412292 100644
--- a/src/qml/qml/qqmltypeloader.cpp
+++ b/src/qml/qml/qqmltypeloader.cpp
@@ -52,6 +52,7 @@
 #include <private/qqmlpropertyvalidator_p.h>
 #include <private/qqmlpropertycachecreator_p.h>
 #include <private/qv4module_p.h>
+#include <private/qqmlirloader_p.h>
 
 #include <QtCore/qdir.h>
 #include <QtCore/qfile.h>
@@ -2135,7 +2136,7 @@ const QList<QQmlTypeData::ScriptReference> &QQmlTypeData::resolvedScripts() cons
     return m_scripts;
 }
 
-QV4::CompiledData::CompilationUnit *QQmlTypeData::compilationUnit() const
+QV4::ExecutableCompilationUnit *QQmlTypeData::compilationUnit() const
 {
     return m_compiledData.data();
 }
@@ -2165,7 +2166,7 @@ bool QQmlTypeData::tryLoadFromDiskCache()
     if (!v4)
         return false;
 
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> unit = QV4::Compiler::Codegen::createUnitForLoading();
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> unit = QV4::ExecutableCompilationUnit::create();
     {
         QString error;
         if (!unit->loadFromDisk(url(), m_backupSourceCode.sourceTimeStamp(), &error)) {
@@ -2175,7 +2176,7 @@ bool QQmlTypeData::tryLoadFromDiskCache()
     }
 
     if (unit->unitData()->flags & QV4::CompiledData::Unit::PendingTypeCompilation) {
-        restoreIR(unit);
+        restoreIR(std::move(*unit));
         return true;
     }
 
@@ -2231,8 +2232,9 @@ bool QQmlTypeData::tryLoadFromDiskCache()
     return true;
 }
 
-void QQmlTypeData::createTypeAndPropertyCaches(const QQmlRefPointer<QQmlTypeNameCache> &typeNameCache,
-                                                const QV4::CompiledData::ResolvedTypeReferenceMap &resolvedTypeCache)
+void QQmlTypeData::createTypeAndPropertyCaches(
+        const QQmlRefPointer<QQmlTypeNameCache> &typeNameCache,
+        const QV4::ResolvedTypeReferenceMap &resolvedTypeCache)
 {
     Q_ASSERT(m_compiledData);
     m_compiledData->typeNameCache = typeNameCache;
@@ -2243,9 +2245,9 @@ void QQmlTypeData::createTypeAndPropertyCaches(const QQmlRefPointer<QQmlTypeName
     QQmlPendingGroupPropertyBindings pendingGroupPropertyBindings;
 
     {
-        QQmlPropertyCacheCreator<QV4::CompiledData::CompilationUnit> propertyCacheCreator(&m_compiledData->propertyCaches,
-                                                                                          &pendingGroupPropertyBindings,
-                                                                                          engine, m_compiledData.data(), &m_importCache);
+        QQmlPropertyCacheCreator<QV4::ExecutableCompilationUnit> propertyCacheCreator(
+                &m_compiledData->propertyCaches, &pendingGroupPropertyBindings, engine,
+                m_compiledData.data(), &m_importCache);
         QQmlCompileError error = propertyCacheCreator.buildMetaObjects();
         if (error.isSet()) {
             setError(error);
@@ -2253,7 +2255,8 @@ void QQmlTypeData::createTypeAndPropertyCaches(const QQmlRefPointer<QQmlTypeName
         }
     }
 
-    QQmlPropertyCacheAliasCreator<QV4::CompiledData::CompilationUnit> aliasCreator(&m_compiledData->propertyCaches, m_compiledData.data());
+    QQmlPropertyCacheAliasCreator<QV4::ExecutableCompilationUnit> aliasCreator(
+            &m_compiledData->propertyCaches, m_compiledData.data());
     aliasCreator.appendAliasPropertiesToMetaObjects();
 
     pendingGroupPropertyBindings.resolveMissingPropertyCaches(engine, &m_compiledData->propertyCaches);
@@ -2345,7 +2348,7 @@ void QQmlTypeData::done()
     }
 
     QQmlRefPointer<QQmlTypeNameCache> typeNameCache;
-    QV4::CompiledData::ResolvedTypeReferenceMap resolvedTypeCache;
+    QV4::ResolvedTypeReferenceMap resolvedTypeCache;
     {
         QQmlCompileError error = buildTypeResolutionCaches(&typeNameCache, &resolvedTypeCache);
         if (error.isSet()) {
@@ -2356,10 +2359,12 @@ void QQmlTypeData::done()
 
     QQmlEngine *const engine = typeLoader()->engine();
 
-    const auto dependencyHasher = [engine, &resolvedTypeCache, this](QCryptographicHash *hash) {
-        if (!resolvedTypeCache.addToHash(hash, engine))
-            return false;
-        return ::addTypeReferenceChecksumsToHash(m_compositeSingletons, hash, engine);
+    const auto dependencyHasher = [engine, &resolvedTypeCache, this]() {
+        QCryptographicHash hash(QCryptographicHash::Md5);
+        return (resolvedTypeCache.addToHash(&hash, engine)
+                    && ::addTypeReferenceChecksumsToHash(m_compositeSingletons, &hash, engine))
+                ? hash.result()
+                : QByteArray();
     };
 
     // verify if any dependencies changed if we're using a cache
@@ -2502,11 +2507,11 @@ void QQmlTypeData::dataReceived(const SourceCodeData &data)
 void QQmlTypeData::initializeFromCachedUnit(const QV4::CompiledData::Unit *unit)
 {
     m_document.reset(new QmlIR::Document(isDebugging()));
-    QmlIR::IRLoader loader(unit, m_document.data());
+    QQmlIRLoader loader(unit, m_document.data());
     loader.load();
     m_document->jsModule.fileName = urlString();
     m_document->jsModule.finalUrl = finalUrlString();
-    m_document->javaScriptCompilationUnit.adopt(new QV4::CompiledData::CompilationUnit(unit));
+    m_document->javaScriptCompilationUnit = QV4::CompiledData::CompilationUnit(unit);
     continueLoadFromIR();
 }
 
@@ -2515,7 +2520,7 @@ bool QQmlTypeData::loadFromSource()
     m_document.reset(new QmlIR::Document(isDebugging()));
     m_document->jsModule.sourceTimeStamp = m_backupSourceCode.sourceTimeStamp();
     QQmlEngine *qmlEngine = typeLoader()->engine();
-    QmlIR::IRBuilder compiler(qmlEngine->handle()->v8Engine->illegalNames());
+    QmlIR::IRBuilder compiler(qmlEngine->handle()->illegalNames());
 
     QString sourceError;
     const QString source = m_backupSourceCode.readAll(&sourceError);
@@ -2541,14 +2546,14 @@ bool QQmlTypeData::loadFromSource()
     return true;
 }
 
-void QQmlTypeData::restoreIR(QQmlRefPointer<QV4::CompiledData::CompilationUnit> unit)
+void QQmlTypeData::restoreIR(QV4::CompiledData::CompilationUnit &&unit)
 {
     m_document.reset(new QmlIR::Document(isDebugging()));
-    QmlIR::IRLoader loader(unit->unitData(), m_document.data());
+    QQmlIRLoader loader(unit.unitData(), m_document.data());
     loader.load();
     m_document->jsModule.fileName = urlString();
     m_document->jsModule.finalUrl = finalUrlString();
-    m_document->javaScriptCompilationUnit = unit;
+    m_document->javaScriptCompilationUnit = std::move(unit);
     continueLoadFromIR();
 }
 
@@ -2647,12 +2652,13 @@ QString QQmlTypeData::stringAt(int index) const
 }
 
 void QQmlTypeData::compile(const QQmlRefPointer<QQmlTypeNameCache> &typeNameCache,
-                           QV4::CompiledData::ResolvedTypeReferenceMap *resolvedTypeCache,
+                           QV4::ResolvedTypeReferenceMap *resolvedTypeCache,
                            const QV4::CompiledData::DependentTypesHasher &dependencyHasher)
 {
     Q_ASSERT(m_compiledData.isNull());
 
-    const bool typeRecompilation = m_document && m_document->javaScriptCompilationUnit && m_document->javaScriptCompilationUnit->unitData()->flags & QV4::CompiledData::Unit::PendingTypeCompilation;
+    const bool typeRecompilation = m_document && m_document->javaScriptCompilationUnit.unitData()
+            && (m_document->javaScriptCompilationUnit.unitData()->flags & QV4::CompiledData::Unit::PendingTypeCompilation);
 
     QQmlEnginePrivate * const enginePrivate = QQmlEnginePrivate::get(typeLoader()->engine());
     QQmlTypeCompiler compiler(enginePrivate, this, m_document.data(), typeNameCache, resolvedTypeCache, dependencyHasher);
@@ -2771,7 +2777,7 @@ void QQmlTypeData::resolveTypes()
 
 QQmlCompileError QQmlTypeData::buildTypeResolutionCaches(
         QQmlRefPointer<QQmlTypeNameCache> *typeNameCache,
-        QV4::CompiledData::ResolvedTypeReferenceMap *resolvedTypeCache
+        QV4::ResolvedTypeReferenceMap *resolvedTypeCache
         ) const
 {
     typeNameCache->adopt(new QQmlTypeNameCache(m_importCache));
@@ -2788,7 +2794,7 @@ QQmlCompileError QQmlTypeData::buildTypeResolutionCaches(
     QQmlEnginePrivate * const engine = QQmlEnginePrivate::get(typeLoader()->engine());
 
     for (auto resolvedType = m_resolvedTypes.constBegin(), end = m_resolvedTypes.constEnd(); resolvedType != end; ++resolvedType) {
-        QScopedPointer<QV4::CompiledData::ResolvedTypeReference> ref(new QV4::CompiledData::ResolvedTypeReference);
+        QScopedPointer<QV4::ResolvedTypeReference> ref(new QV4::ResolvedTypeReference);
         QQmlType qmlType = resolvedType->type;
         if (resolvedType->typeData) {
             if (resolvedType->needsCreation && qmlType.isCompositeSingleton()) {
@@ -3019,7 +3025,8 @@ QQmlRefPointer<QQmlScriptData> QQmlScriptBlob::scriptData() const
 void QQmlScriptBlob::dataReceived(const SourceCodeData &data)
 {
     if (!disableDiskCache() || forceDiskCache()) {
-        QQmlRefPointer<QV4::CompiledData::CompilationUnit> unit = QV4::Compiler::Codegen::createUnitForLoading();
+        QQmlRefPointer<QV4::ExecutableCompilationUnit> unit
+                = QV4::ExecutableCompilationUnit::create();
         QString error;
         if (unit->loadFromDisk(url(), data.sourceTimeStamp(), &error)) {
             initializeFromCompilationUnit(unit);
@@ -3044,11 +3051,12 @@ void QQmlScriptBlob::dataReceived(const SourceCodeData &data)
         return;
     }
 
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> unit;
+    QV4::CompiledData::CompilationUnit unit;
 
     if (m_isModule) {
         QList<QQmlJS::DiagnosticMessage> diagnostics;
-        unit = QV4::ExecutionEngine::compileModule(isDebugging(), urlString(), source, data.sourceTimeStamp(), &diagnostics);
+        unit = QV4::Compiler::Codegen::compileModule(isDebugging(), urlString(), source,
+                                                     data.sourceTimeStamp(), &diagnostics);
         QList<QQmlError> errors = QQmlEnginePrivate::qmlErrorFromDiagnostics(urlString(), diagnostics);
         if (!errors.isEmpty()) {
             setError(errors);
@@ -3063,44 +3071,43 @@ void QQmlScriptBlob::dataReceived(const SourceCodeData &data)
         irUnit.jsParserEngine.setDirectives(&collector);
 
         QList<QQmlError> errors;
-        unit = QV4::Script::precompile(
-                    &irUnit.jsModule, &irUnit.jsParserEngine, &irUnit.jsGenerator, urlString(), finalUrlString(),
-                    source, &errors, QV4::Compiler::ContextType::ScriptImportedByQML);
-        // No need to addref on unit, it's initial refcount is 1
+        irUnit.javaScriptCompilationUnit = QV4::Script::precompile(
+                     &irUnit.jsModule, &irUnit.jsParserEngine, &irUnit.jsGenerator, urlString(), finalUrlString(),
+                     source, &errors, QV4::Compiler::ContextType::ScriptImportedByQML);
+
         source.clear();
         if (!errors.isEmpty()) {
             setError(errors);
             return;
         }
-        if (!unit) {
-            unit.adopt(new QV4::CompiledData::CompilationUnit);
-        }
-        irUnit.javaScriptCompilationUnit = unit;
 
         QmlIR::QmlUnitGenerator qmlGenerator;
         qmlGenerator.generate(irUnit);
+        unit = std::move(irUnit.javaScriptCompilationUnit);
     }
 
+    auto executableUnit = QV4::ExecutableCompilationUnit::create(std::move(unit));
+
     if ((!disableDiskCache() || forceDiskCache()) && !isDebugging()) {
         QString errorString;
-        if (unit->saveToDisk(url(), &errorString)) {
+        if (executableUnit->saveToDisk(url(), &errorString)) {
             QString error;
-            if (!unit->loadFromDisk(url(), data.sourceTimeStamp(), &error)) {
+            if (!executableUnit->loadFromDisk(url(), data.sourceTimeStamp(), &error)) {
                 // ignore error, keep using the in-memory compilation unit.
             }
         } else {
-            qCDebug(DBG_DISK_CACHE()) << "Error saving cached version of" << unit->fileName() << "to disk:" << errorString;
+            qCDebug(DBG_DISK_CACHE()) << "Error saving cached version of"
+                                      << executableUnit->fileName() << "to disk:" << errorString;
         }
     }
 
-    initializeFromCompilationUnit(unit);
+    initializeFromCompilationUnit(executableUnit);
 }
 
 void QQmlScriptBlob::initializeFromCachedUnit(const QV4::CompiledData::Unit *unit)
 {
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> compilationUnit;
-    compilationUnit.adopt(new QV4::CompiledData::CompilationUnit(unit, urlString(), finalUrlString()));
-    initializeFromCompilationUnit(compilationUnit);
+    initializeFromCompilationUnit(QV4::ExecutableCompilationUnit::create(
+            QV4::CompiledData::CompilationUnit(unit, urlString(), finalUrlString())));
 }
 
 void QQmlScriptBlob::done()
@@ -3165,7 +3172,7 @@ void QQmlScriptBlob::scriptImported(const QQmlRefPointer<QQmlScriptBlob> &blob,
     m_scripts << ref;
 }
 
-void QQmlScriptBlob::initializeFromCompilationUnit(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &unit)
+void QQmlScriptBlob::initializeFromCompilationUnit(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &unit)
 {
     Q_ASSERT(!m_scriptData);
     m_scriptData.adopt(new QQmlScriptData());
@@ -3175,7 +3182,7 @@ void QQmlScriptBlob::initializeFromCompilationUnit(const QQmlRefPointer<QV4::Com
 
     m_importCache.setBaseUrl(finalUrl(), finalUrlString());
 
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> script = m_scriptData->m_precompiledScript;
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> script = m_scriptData->m_precompiledScript;
 
     if (!m_isModule) {
         QList<QQmlError> errors;
diff --git a/src/qml/qml/qqmltypeloader_p.h b/src/qml/qml/qqmltypeloader_p.h
index 987e47222d..d87812d48e 100644
--- a/src/qml/qml/qqmltypeloader_p.h
+++ b/src/qml/qml/qqmltypeloader_p.h
@@ -70,6 +70,7 @@
 #include <private/qqmldirparser_p.h>
 #include <private/qflagpointer_p.h>
 #include <private/qqmlirbuilder_p.h>
+#include <private/qv4executablecompilationunit_p.h>
 
 #include <private/qv4value_p.h>
 #include <private/qv4script_p.h>
@@ -453,7 +454,7 @@ public:
 
     const QList<ScriptReference> &resolvedScripts() const;
 
-    QV4::CompiledData::CompilationUnit *compilationUnit() const;
+    QV4::ExecutableCompilationUnit *compilationUnit() const;
 
     // Used by QQmlComponent to get notifications
     struct TypeDataCallback {
@@ -477,18 +478,18 @@ protected:
 private:
     bool tryLoadFromDiskCache();
     bool loadFromSource();
-    void restoreIR(QQmlRefPointer<QV4::CompiledData::CompilationUnit> unit);
+    void restoreIR(QV4::CompiledData::CompilationUnit &&unit);
     void continueLoadFromIR();
     void resolveTypes();
     QQmlCompileError buildTypeResolutionCaches(
             QQmlRefPointer<QQmlTypeNameCache> *typeNameCache,
-            QV4::CompiledData::ResolvedTypeReferenceMap *resolvedTypeCache
+            QV4::ResolvedTypeReferenceMap *resolvedTypeCache
             ) const;
     void compile(const QQmlRefPointer<QQmlTypeNameCache> &typeNameCache,
-                 QV4::CompiledData::ResolvedTypeReferenceMap *resolvedTypeCache,
+                 QV4::ResolvedTypeReferenceMap *resolvedTypeCache,
                  const QV4::CompiledData::DependentTypesHasher &dependencyHasher);
     void createTypeAndPropertyCaches(const QQmlRefPointer<QQmlTypeNameCache> &typeNameCache,
-                                      const QV4::CompiledData::ResolvedTypeReferenceMap &resolvedTypeCache);
+                                      const QV4::ResolvedTypeReferenceMap &resolvedTypeCache);
     bool resolveType(const QString &typeName, int &majorVersion, int &minorVersion,
                      TypeReference &ref, int lineNumber = -1, int columnNumber = -1,
                      bool reportErrors = true,
@@ -512,7 +513,7 @@ private:
     QMap<int, TypeReference> m_resolvedTypes;
     bool m_typesResolved:1;
 
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> m_compiledData;
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> m_compiledData;
 
     QList<TypeDataCallback *> m_callbacks;
 
@@ -542,7 +543,7 @@ public:
 
     QV4::ReturnedValue scriptValueForContext(QQmlContextData *parentCtxt);
 
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> compilationUnit() const { return m_precompiledScript; }
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> compilationUnit() const { return m_precompiledScript; }
 
 protected:
     void clear() override; // From QQmlCleanup
@@ -554,7 +555,7 @@ private:
     QQmlContextData *qmlContextDataForContext(QQmlContextData *parentQmlContextData);
 
     bool m_loaded;
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> m_precompiledScript;
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> m_precompiledScript;
     QV4::PersistentValue m_value;
 };
 
@@ -587,7 +588,7 @@ protected:
 
 private:
     void scriptImported(const QQmlRefPointer<QQmlScriptBlob> &blob, const QV4::CompiledData::Location &location, const QString &qualifier, const QString &nameSpace) override;
-    void initializeFromCompilationUnit(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &unit);
+    void initializeFromCompilationUnit(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &unit);
 
     QList<ScriptReference> m_scripts;
     QQmlRefPointer<QQmlScriptData> m_scriptData;
diff --git a/src/qml/qml/qqmltypewrapper.cpp b/src/qml/qml/qqmltypewrapper.cpp
index 236daac75c..9db089c330 100644
--- a/src/qml/qml/qqmltypewrapper.cpp
+++ b/src/qml/qml/qqmltypewrapper.cpp
@@ -418,7 +418,7 @@ ReturnedValue QQmlTypeWrapper::virtualInstanceOf(const Object *typeObject, const
             return Encode(false);
 
         QQmlRefPointer<QQmlTypeData> td = qenginepriv->typeLoader.getType(typeWrapper->d()->type().sourceUrl());
-        CompiledData::CompilationUnit *cu = td->compilationUnit();
+        ExecutableCompilationUnit *cu = td->compilationUnit();
         myQmlType = qenginepriv->metaObjectForType(cu->metaTypeId);
     } else {
         myQmlType = qenginepriv->metaObjectForType(myTypeId);
diff --git a/src/qml/qml/qqmlvaluetype.cpp b/src/qml/qml/qqmlvaluetype.cpp
index f08005fd20..fce753cd26 100644
--- a/src/qml/qml/qqmlvaluetype.cpp
+++ b/src/qml/qml/qqmlvaluetype.cpp
@@ -39,6 +39,7 @@
 
 #include "qqmlvaluetype_p.h"
 
+#include <QtCore/qmutex.h>
 #include <private/qqmlglobal_p.h>
 #include <QtCore/qdebug.h>
 #include <private/qmetaobjectbuilder_p.h>
diff --git a/src/qml/qml/qqmlvmemetaobject.cpp b/src/qml/qml/qqmlvmemetaobject.cpp
index 5d13415513..2881e71805 100644
--- a/src/qml/qml/qqmlvmemetaobject.cpp
+++ b/src/qml/qml/qqmlvmemetaobject.cpp
@@ -316,7 +316,7 @@ QAbstractDynamicMetaObject *QQmlInterceptorMetaObject::toDynamicMetaObject(QObje
 
 QQmlVMEMetaObject::QQmlVMEMetaObject(QV4::ExecutionEngine *engine,
                                      QObject *obj,
-                                     const QQmlRefPointer<QQmlPropertyCache> &cache, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &qmlCompilationUnit, int qmlObjectId)
+                                     const QQmlRefPointer<QQmlPropertyCache> &cache, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &qmlCompilationUnit, int qmlObjectId)
     : QQmlInterceptorMetaObject(obj, cache),
       engine(engine),
       ctxt(QQmlData::get(obj, true)->outerContext),
diff --git a/src/qml/qml/qqmlvmemetaobject_p.h b/src/qml/qml/qqmlvmemetaobject_p.h
index 2371d70f10..5025987586 100644
--- a/src/qml/qml/qqmlvmemetaobject_p.h
+++ b/src/qml/qml/qqmlvmemetaobject_p.h
@@ -144,7 +144,7 @@ class QQmlVMEMetaObjectEndpoint;
 class Q_QML_PRIVATE_EXPORT QQmlVMEMetaObject : public QQmlInterceptorMetaObject
 {
 public:
-    QQmlVMEMetaObject(QV4::ExecutionEngine *engine, QObject *obj, const QQmlRefPointer<QQmlPropertyCache> &cache, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &qmlCompilationUnit, int qmlObjectId);
+    QQmlVMEMetaObject(QV4::ExecutionEngine *engine, QObject *obj, const QQmlRefPointer<QQmlPropertyCache> &cache, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &qmlCompilationUnit, int qmlObjectId);
     ~QQmlVMEMetaObject() override;
 
     bool aliasTarget(int index, QObject **target, int *coreIndex, int *valueTypeIndex) const;
@@ -226,7 +226,7 @@ public:
 
     // keep a reference to the compilation unit in order to still
     // do property access when the context has been invalidated.
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> compilationUnit;
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> compilationUnit;
     const QV4::CompiledData::Object *compiledObject;
 };
 
diff --git a/src/qml/qml/qqmlxmlhttprequest.cpp b/src/qml/qml/qqmlxmlhttprequest.cpp
index c6b7f2ab3f..b435f8ef66 100644
--- a/src/qml/qml/qqmlxmlhttprequest.cpp
+++ b/src/qml/qml/qqmlxmlhttprequest.cpp
@@ -95,7 +95,7 @@ struct QQmlXMLHttpRequestData {
 
 static inline QQmlXMLHttpRequestData *xhrdata(ExecutionEngine *v4)
 {
-    return (QQmlXMLHttpRequestData *)v4->v8Engine->xmlHttpRequestData();
+    return (QQmlXMLHttpRequestData *)v4->xmlHttpRequestData();
 }
 
 QQmlXMLHttpRequestData::QQmlXMLHttpRequestData()
@@ -591,7 +591,7 @@ ReturnedValue NodePrototype::getProto(ExecutionEngine *v4)
     if (d->nodePrototype.isUndefined()) {
         ScopedObject p(scope, v4->memoryManager->allocate<NodePrototype>());
         d->nodePrototype.set(v4, p);
-        v4->v8Engine->freezeObject(p);
+        v4->freezeObject(p);
     }
     return d->nodePrototype.value();
 }
@@ -640,7 +640,7 @@ ReturnedValue Element::prototype(ExecutionEngine *engine)
         p->setPrototypeUnchecked((pp = NodePrototype::getProto(engine)));
         p->defineAccessorProperty(QStringLiteral("tagName"), NodePrototype::method_get_nodeName, nullptr);
         d->elementPrototype.set(engine, p);
-        engine->v8Engine->freezeObject(p);
+        engine->freezeObject(p);
     }
     return d->elementPrototype.value();
 }
@@ -657,7 +657,7 @@ ReturnedValue Attr::prototype(ExecutionEngine *engine)
         p->defineAccessorProperty(QStringLiteral("value"), method_value, nullptr);
         p->defineAccessorProperty(QStringLiteral("ownerElement"), method_ownerElement, nullptr);
         d->attrPrototype.set(engine, p);
-        engine->v8Engine->freezeObject(p);
+        engine->freezeObject(p);
     }
     return d->attrPrototype.value();
 }
@@ -713,7 +713,7 @@ ReturnedValue CharacterData::prototype(ExecutionEngine *v4)
         p->defineAccessorProperty(QStringLiteral("data"), NodePrototype::method_get_nodeValue, nullptr);
         p->defineAccessorProperty(QStringLiteral("length"), method_length, nullptr);
         d->characterDataPrototype.set(v4, p);
-        v4->v8Engine->freezeObject(p);
+        v4->freezeObject(p);
     }
     return d->characterDataPrototype.value();
 }
@@ -749,7 +749,7 @@ ReturnedValue Text::prototype(ExecutionEngine *v4)
         p->defineAccessorProperty(QStringLiteral("isElementContentWhitespace"), method_isElementContentWhitespace, nullptr);
         p->defineAccessorProperty(QStringLiteral("wholeText"), method_wholeText, nullptr);
         d->textPrototype.set(v4, p);
-        v4->v8Engine->freezeObject(p);
+        v4->freezeObject(p);
     }
     return d->textPrototype.value();
 }
@@ -764,7 +764,7 @@ ReturnedValue CDATA::prototype(ExecutionEngine *v4)
         ScopedObject pp(scope);
         p->setPrototypeUnchecked((pp = Text::prototype(v4)));
         d->cdataPrototype.set(v4, p);
-        v4->v8Engine->freezeObject(p);
+        v4->freezeObject(p);
     }
     return d->cdataPrototype.value();
 }
@@ -782,7 +782,7 @@ ReturnedValue Document::prototype(ExecutionEngine *v4)
         p->defineAccessorProperty(QStringLiteral("xmlStandalone"), method_xmlStandalone, nullptr);
         p->defineAccessorProperty(QStringLiteral("documentElement"), method_documentElement, nullptr);
         d->documentPrototype.set(v4, p);
-        v4->v8Engine->freezeObject(p);
+        v4->freezeObject(p);
     }
     return d->documentPrototype.value();
 }
@@ -1646,7 +1646,7 @@ struct QQmlXMLHttpRequestCtor : public FunctionObject
         Scope scope(f->engine());
         const QQmlXMLHttpRequestCtor *ctor = static_cast<const QQmlXMLHttpRequestCtor *>(f);
 
-        QQmlXMLHttpRequest *r = new QQmlXMLHttpRequest(scope.engine->v8Engine->networkAccessManager(), scope.engine);
+        QQmlXMLHttpRequest *r = new QQmlXMLHttpRequest(scope.engine->qmlEngine()->networkAccessManager(), scope.engine);
         Scoped<QQmlXMLHttpRequestWrapper> w(scope, scope.engine->memoryManager->allocate<QQmlXMLHttpRequestWrapper>(r));
         ScopedObject proto(scope, ctor->d()->proto);
         w->setPrototypeUnchecked(proto);
diff --git a/src/qml/qml/v8/qqmlbuiltinfunctions.cpp b/src/qml/qml/v8/qqmlbuiltinfunctions.cpp
index 3bc588b50e..4838ef3814 100644
--- a/src/qml/qml/v8/qqmlbuiltinfunctions.cpp
+++ b/src/qml/qml/v8/qqmlbuiltinfunctions.cpp
@@ -47,7 +47,6 @@
 #if QT_CONFIG(qml_locale)
 #include <private/qqmllocale_p.h>
 #endif
-#include <private/qv8engine_p.h>
 #include <private/qqmldelayedcallqueue_p.h>
 #include <QFileInfo>
 
@@ -1684,10 +1683,8 @@ ReturnedValue ConsoleObject::method_time(const FunctionObject *b, const Value *,
     if (argc != 1)
         THROW_GENERIC_ERROR("console.time(): Invalid arguments");
 
-    QV8Engine *v8engine = scope.engine->v8Engine;
-
     QString name = argv[0].toQStringNoThrow();
-    v8engine->startTimer(name);
+    scope.engine->startTimer(name);
     return QV4::Encode::undefined();
 }
 
@@ -1697,11 +1694,9 @@ ReturnedValue ConsoleObject::method_timeEnd(const FunctionObject *b, const Value
     if (argc != 1)
         THROW_GENERIC_ERROR("console.timeEnd(): Invalid arguments");
 
-    QV8Engine *v8engine = scope.engine->v8Engine;
-
     QString name = argv[0].toQStringNoThrow();
     bool wasRunning;
-    qint64 elapsed = v8engine->stopTimer(name, &wasRunning);
+    qint64 elapsed = scope.engine->stopTimer(name, &wasRunning);
     if (wasRunning) {
         qDebug("%s: %llims", qPrintable(name), elapsed);
     }
@@ -1717,13 +1712,12 @@ ReturnedValue ConsoleObject::method_count(const FunctionObject *b, const Value *
 
     Scope scope(b);
     QV4::ExecutionEngine *v4 = scope.engine;
-    QV8Engine *v8engine = scope.engine->v8Engine;
 
     QV4::CppStackFrame *frame = v4->currentStackFrame;
 
     QString scriptName = frame->source();
 
-    int value = v8engine->consoleCountHelper(scriptName, frame->lineNumber(), 0);
+    int value = v4->consoleCountHelper(scriptName, frame->lineNumber(), 0);
     QString message = name + QLatin1String(": ") + QString::number(value);
 
     QMessageLogger(qPrintable(scriptName), frame->lineNumber(),
@@ -1956,7 +1950,8 @@ ReturnedValue GlobalExtensions::method_qsTr(const FunctionObject *b, const Value
         CppStackFrame *frame = scope.engine->currentStackFrame;
         // The first non-empty source URL in the call stack determines the translation context.
         while (frame && context.isEmpty()) {
-            if (CompiledData::CompilationUnit *unit = frame->v4Function->compilationUnit) {
+            if (CompiledData::CompilationUnitBase *baseUnit = frame->v4Function->compilationUnit) {
+                const auto *unit = static_cast<const CompiledData::CompilationUnit *>(baseUnit);
                 QString fileName = unit->fileName();
                 QUrl url(unit->fileName());
                 if (url.isValid() && url.isRelative()) {
@@ -2147,8 +2142,7 @@ function.
 */
 ReturnedValue QtObject::method_callLater(const FunctionObject *b, const Value *thisObject, const Value *argv, int argc)
 {
-    QV8Engine *v8engine = b->engine()->v8Engine;
-    return v8engine->delayedCallQueue()->addUniquelyAndExecuteLater(b, thisObject, argv, argc);
+    return b->engine()->delayedCallQueue()->addUniquelyAndExecuteLater(b, thisObject, argv, argc);
 }
 
 QT_END_NAMESPACE
diff --git a/src/qml/qml/v8/qv8engine.cpp b/src/qml/qml/v8/qv8engine.cpp
deleted file mode 100644
index d76344b613..0000000000
--- a/src/qml/qml/v8/qv8engine.cpp
+++ /dev/null
@@ -1,331 +0,0 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the QtQml module of the Qt Toolkit.
-**
-** $QT_BEGIN_LICENSE:LGPL$
-** Commercial License Usage
-** Licensees holding valid commercial Qt licenses may use this file in
-** accordance with the commercial license agreement provided with the
-** Software or, alternatively, in accordance with the terms contained in
-** a written agreement between you and The Qt Company. For licensing terms
-** and conditions see https://www.qt.io/terms-conditions. For further
-** information use the contact form at https://www.qt.io/contact-us.
-**
-** GNU Lesser General Public License Usage
-** Alternatively, this file may be used under the terms of the GNU Lesser
-** General Public License version 3 as published by the Free Software
-** Foundation and appearing in the file LICENSE.LGPL3 included in the
-** packaging of this file. Please review the following information to
-** ensure the GNU Lesser General Public License version 3 requirements
-** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
-**
-** GNU General Public License Usage
-** Alternatively, this file may be used under the terms of the GNU
-** General Public License version 2.0 or (at your option) the GNU General
-** Public license version 3 or any later version approved by the KDE Free
-** Qt Foundation. The licenses are as published by the Free Software
-** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
-** included in the packaging of this file. Please review the following
-** information to ensure the GNU General Public License requirements will
-** be met: https://www.gnu.org/licenses/gpl-2.0.html and
-** https://www.gnu.org/licenses/gpl-3.0.html.
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
-
-#include "qv8engine_p.h"
-
-#if QT_CONFIG(qml_sequence_object)
-#include "qv4sequenceobject_p.h"
-#endif
-
-#include "private/qjsengine_p.h"
-
-#include <private/qqmlbuiltinfunctions_p.h>
-#include <private/qqmllist_p.h>
-#include <private/qqmlengine_p.h>
-#if QT_CONFIG(qml_xml_http_request)
-#include <private/qqmlxmlhttprequest_p.h>
-#endif
-#if QT_CONFIG(qml_locale)
-#include <private/qqmllocale_p.h>
-#endif
-#include <private/qqmlglobal_p.h>
-#include <private/qqmlmemoryprofiler_p.h>
-#include <private/qqmlplatform_p.h>
-#include <private/qjsvalue_p.h>
-#include <private/qqmltypewrapper_p.h>
-#include <private/qqmlvaluetypewrapper_p.h>
-#include <private/qqmllistwrapper_p.h>
-#include <private/qv4scopedvalue_p.h>
-
-#include "qv4domerrors_p.h"
-#include "qv4sqlerrors_p.h"
-
-#include <QtCore/qjsonarray.h>
-#include <QtCore/qjsonobject.h>
-#include <QtCore/qjsonvalue.h>
-#include <QtCore/qdatetime.h>
-#include <QtCore/qdatastream.h>
-#include <private/qsimd_p.h>
-
-#include <private/qv4value_p.h>
-#include <private/qv4dateobject_p.h>
-#include <private/qv4objectiterator_p.h>
-#include <private/qv4qobjectwrapper_p.h>
-#include <private/qv4mm_p.h>
-#include <private/qv4objectproto_p.h>
-#include <private/qv4globalobject_p.h>
-#include <private/qv4regexpobject_p.h>
-#include <private/qv4variantobject_p.h>
-#include <private/qv4script_p.h>
-#include <private/qv4include_p.h>
-#include <private/qv4jsonobject_p.h>
-#include <private/qv4identifiertable_p.h>
-
-Q_DECLARE_METATYPE(QList<int>)
-
-
-// XXX TODO: Need to check all the global functions will also work in a worker script where the
-// QQmlEngine is not available
-QT_BEGIN_NAMESPACE
-
-template <typename ReturnType>
-ReturnType convertJSValueToVariantType(const QJSValue &value)
-{
-    return value.toVariant().value<ReturnType>();
-}
-
-static void saveJSValue(QDataStream &stream, const void *data)
-{
-    const QJSValue *jsv = reinterpret_cast<const QJSValue *>(data);
-    quint32 isNullOrUndefined = 0;
-    if (jsv->isNull())
-        isNullOrUndefined |= 0x1;
-    if (jsv->isUndefined())
-        isNullOrUndefined |= 0x2;
-    stream << isNullOrUndefined;
-    if (!isNullOrUndefined)
-        reinterpret_cast<const QJSValue*>(data)->toVariant().save(stream);
-}
-
-static void restoreJSValue(QDataStream &stream, void *data)
-{
-    QJSValue *jsv = reinterpret_cast<QJSValue*>(data);
-
-    quint32 isNullOrUndefined;
-    stream >> isNullOrUndefined;
-
-    if (isNullOrUndefined & 0x1) {
-        *jsv = QJSValue(QJSValue::NullValue);
-    } else if (isNullOrUndefined & 0x2) {
-        *jsv = QJSValue();
-    } else {
-        QVariant v;
-        v.load(stream);
-        QJSValuePrivate::setVariant(jsv, v);
-    }
-}
-
-QV8Engine::QV8Engine(QV4::ExecutionEngine *v4)
-    : m_engine(nullptr)
-    , m_v4Engine(v4)
-#if QT_CONFIG(qml_xml_http_request)
-    , m_xmlHttpRequestData(nullptr)
-#endif
-{
-#ifndef Q_OS_WASM // wasm does not have working simd QTBUG-63924
-#ifdef Q_PROCESSOR_X86_32
-    if (!qCpuHasFeature(SSE2)) {
-        qFatal("This program requires an X86 processor that supports SSE2 extension, at least a Pentium 4 or newer");
-    }
-#endif
-#endif
-
-    QML_MEMORY_SCOPE_STRING("QV8Engine::QV8Engine");
-    qMetaTypeId<QJSValue>();
-    qMetaTypeId<QList<int> >();
-
-    if (!QMetaType::hasRegisteredConverterFunction<QJSValue, QVariantMap>())
-        QMetaType::registerConverter<QJSValue, QVariantMap>(convertJSValueToVariantType<QVariantMap>);
-    if (!QMetaType::hasRegisteredConverterFunction<QJSValue, QVariantList>())
-        QMetaType::registerConverter<QJSValue, QVariantList>(convertJSValueToVariantType<QVariantList>);
-    if (!QMetaType::hasRegisteredConverterFunction<QJSValue, QStringList>())
-        QMetaType::registerConverter<QJSValue, QStringList>(convertJSValueToVariantType<QStringList>);
-    QMetaType::registerStreamOperators(qMetaTypeId<QJSValue>(), saveJSValue, restoreJSValue);
-
-    m_delayedCallQueue.init(m_v4Engine);
-
-    QV4::QObjectWrapper::initializeBindings(m_v4Engine);
-}
-
-QV8Engine::~QV8Engine()
-{
-    qDeleteAll(m_extensionData);
-    m_extensionData.clear();
-
-#if QT_CONFIG(qml_xml_http_request)
-    qt_rem_qmlxmlhttprequest(m_v4Engine, m_xmlHttpRequestData);
-    m_xmlHttpRequestData = nullptr;
-#endif
-}
-
-#if QT_CONFIG(qml_network)
-QNetworkAccessManager *QV8Engine::networkAccessManager()
-{
-    return QQmlEnginePrivate::get(m_engine)->getNetworkAccessManager();
-}
-#endif
-
-const QSet<QString> &QV8Engine::illegalNames() const
-{
-    return m_illegalNames;
-}
-
-void QV8Engine::initializeGlobal()
-{
-    QV4::Scope scope(m_v4Engine);
-    QV4::GlobalExtensions::init(m_v4Engine->globalObject, QJSEngine::AllExtensions);
-
-    QV4::ScopedObject qt(scope, m_v4Engine->memoryManager->allocate<QV4::QtObject>(m_engine));
-    m_v4Engine->globalObject->defineDefaultProperty(QStringLiteral("Qt"), qt);
-
-#if QT_CONFIG(qml_locale)
-    QQmlLocale::registerStringLocaleCompare(m_v4Engine);
-    QQmlDateExtension::registerExtension(m_v4Engine);
-    QQmlNumberExtension::registerExtension(m_v4Engine);
-#endif
-
-#if QT_CONFIG(qml_xml_http_request)
-    qt_add_domexceptions(m_v4Engine);
-    m_xmlHttpRequestData = qt_add_qmlxmlhttprequest(m_v4Engine);
-#endif
-
-    qt_add_sqlexceptions(m_v4Engine);
-
-    {
-        for (uint i = 0; i < m_v4Engine->globalObject->internalClass()->size; ++i) {
-            if (m_v4Engine->globalObject->internalClass()->nameMap.at(i).isString()) {
-                QV4::PropertyKey id = m_v4Engine->globalObject->internalClass()->nameMap.at(i);
-                m_illegalNames.insert(id.toQString());
-            }
-        }
-    }
-}
-
-static void freeze_recursive(QV4::ExecutionEngine *v4, QV4::Object *object)
-{
-    if (object->as<QV4::QObjectWrapper>())
-        return;
-
-    QV4::Scope scope(v4);
-
-    bool instanceOfObject = false;
-    QV4::ScopedObject p(scope, object->getPrototypeOf());
-    while (p) {
-        if (p->d() == v4->objectPrototype()->d()) {
-            instanceOfObject = true;
-            break;
-        }
-        p = p->getPrototypeOf();
-    }
-    if (!instanceOfObject)
-        return;
-
-    QV4::Heap::InternalClass *frozen = object->internalClass()->propertiesFrozen();
-    if (object->internalClass() == frozen)
-        return;
-    object->setInternalClass(frozen);
-
-    QV4::ScopedObject o(scope);
-    for (uint i = 0; i < frozen->size; ++i) {
-        if (!frozen->nameMap.at(i).isStringOrSymbol())
-            continue;
-        o = *object->propertyData(i);
-        if (o)
-            freeze_recursive(v4, o);
-    }
-}
-
-void QV8Engine::freezeObject(const QV4::Value &value)
-{
-    QV4::Scope scope(m_v4Engine);
-    QV4::ScopedObject o(scope, value);
-    freeze_recursive(m_v4Engine, o);
-}
-
-struct QV8EngineRegistrationData
-{
-    QV8EngineRegistrationData() : extensionCount(0) {}
-
-    QMutex mutex;
-    int extensionCount;
-};
-Q_GLOBAL_STATIC(QV8EngineRegistrationData, registrationData);
-
-QMutex *QV8Engine::registrationMutex()
-{
-    return &registrationData()->mutex;
-}
-
-int QV8Engine::registerExtension()
-{
-    return registrationData()->extensionCount++;
-}
-
-void QV8Engine::setExtensionData(int index, Deletable *data)
-{
-    if (m_extensionData.count() <= index)
-        m_extensionData.resize(index + 1);
-
-    if (m_extensionData.at(index))
-        delete m_extensionData.at(index);
-
-    m_extensionData[index] = data;
-}
-
-void QV8Engine::initQmlGlobalObject()
-{
-    initializeGlobal();
-    freezeObject(*m_v4Engine->globalObject);
-}
-
-void QV8Engine::setEngine(QQmlEngine *engine)
-{
-    m_engine = engine;
-    initQmlGlobalObject();
-}
-
-void QV8Engine::startTimer(const QString &timerName)
-{
-    if (!m_time.isValid())
-        m_time.start();
-    m_startedTimers[timerName] = m_time.elapsed();
-}
-
-qint64 QV8Engine::stopTimer(const QString &timerName, bool *wasRunning)
-{
-    if (!m_startedTimers.contains(timerName)) {
-        *wasRunning = false;
-        return 0;
-    }
-    *wasRunning = true;
-    qint64 startedAt = m_startedTimers.take(timerName);
-    return m_time.elapsed() - startedAt;
-}
-
-int QV8Engine::consoleCountHelper(const QString &file, quint16 line, quint16 column)
-{
-    const QString key = file + QString::number(line) + QString::number(column);
-    int number = m_consoleCount.value(key, 0);
-    number++;
-    m_consoleCount.insert(key, number);
-    return number;
-}
-
-QT_END_NAMESPACE
-
diff --git a/src/qml/qml/v8/qv8engine_p.h b/src/qml/qml/v8/qv8engine_p.h
deleted file mode 100644
index f9b69cfacc..0000000000
--- a/src/qml/qml/v8/qv8engine_p.h
+++ /dev/null
@@ -1,228 +0,0 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the QtQml module of the Qt Toolkit.
-**
-** $QT_BEGIN_LICENSE:LGPL$
-** Commercial License Usage
-** Licensees holding valid commercial Qt licenses may use this file in
-** accordance with the commercial license agreement provided with the
-** Software or, alternatively, in accordance with the terms contained in
-** a written agreement between you and The Qt Company. For licensing terms
-** and conditions see https://www.qt.io/terms-conditions. For further
-** information use the contact form at https://www.qt.io/contact-us.
-**
-** GNU Lesser General Public License Usage
-** Alternatively, this file may be used under the terms of the GNU Lesser
-** General Public License version 3 as published by the Free Software
-** Foundation and appearing in the file LICENSE.LGPL3 included in the
-** packaging of this file. Please review the following information to
-** ensure the GNU Lesser General Public License version 3 requirements
-** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
-**
-** GNU General Public License Usage
-** Alternatively, this file may be used under the terms of the GNU
-** General Public License version 2.0 or (at your option) the GNU General
-** Public license version 3 or any later version approved by the KDE Free
-** Qt Foundation. The licenses are as published by the Free Software
-** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
-** included in the packaging of this file. Please review the following
-** information to ensure the GNU General Public License requirements will
-** be met: https://www.gnu.org/licenses/gpl-2.0.html and
-** https://www.gnu.org/licenses/gpl-3.0.html.
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
-
-#ifndef QQMLV8ENGINE_P_H
-#define QQMLV8ENGINE_P_H
-
-//
-//  W A R N I N G
-//  -------------
-//
-// This file is not part of the Qt API.  It exists purely as an
-// implementation detail.  This header file may change from version to
-// version without notice, or even be removed.
-//
-// We mean it.
-//
-
-#include <QtCore/qglobal.h>
-#include <QtCore/qvariant.h>
-#include <QtCore/qset.h>
-#include <QtCore/qmutex.h>
-#include <QtCore/qstack.h>
-#include <QtCore/qstringlist.h>
-#include <QtCore/QElapsedTimer>
-#include <QtCore/QThreadStorage>
-
-#include <QtQml/qjsengine.h>
-#include "private/qintrusivelist_p.h"
-
-
-#include <private/qv4value_p.h>
-#include <private/qv4identifier_p.h>
-#include <private/qv4context_p.h>
-#include <private/qv4stackframe_p.h>
-#include <private/qqmldelayedcallqueue_p.h>
-
-QT_BEGIN_NAMESPACE
-
-namespace QV4 {
-    struct ArrayObject;
-    struct ExecutionEngine;
-    struct QObjectMethod;
-}
-
-#define V4_DEFINE_EXTENSION(dataclass, datafunction) \
-    static inline dataclass *datafunction(QV4::ExecutionEngine *engine) \
-    { \
-        static int extensionId = -1; \
-        if (extensionId == -1) { \
-            QV8Engine::registrationMutex()->lock(); \
-            if (extensionId == -1) \
-                extensionId = QV8Engine::registerExtension(); \
-            QV8Engine::registrationMutex()->unlock(); \
-        } \
-        dataclass *rv = (dataclass *)engine->v8Engine->extensionData(extensionId); \
-        if (!rv) { \
-            rv = new dataclass(engine); \
-            engine->v8Engine->setExtensionData(extensionId, rv); \
-        } \
-        return rv; \
-    } \
-
-// Used to allow a QObject method take and return raw V4 handles without having to expose
-// 48 in the public API.
-// Use like this:
-//     class MyClass : public QObject {
-//         Q_OBJECT
-//         ...
-//         Q_INVOKABLE void myMethod(QQmlV4Function*);
-//     };
-// The QQmlV8Function - and consequently the arguments and return value - only remains
-// valid during the call.  If the return value isn't set within myMethod(), the will return
-// undefined.
-
-class QQmlV4Function
-{
-public:
-    int length() const { return callData->argc(); }
-    QV4::ReturnedValue operator[](int idx) const { return (idx < callData->argc() ? callData->args[idx].asReturnedValue() : QV4::Encode::undefined()); }
-    void setReturnValue(QV4::ReturnedValue rv) { *retVal = rv; }
-    QV4::ExecutionEngine *v4engine() const { return e; }
-private:
-    friend struct QV4::QObjectMethod;
-    QQmlV4Function();
-    QQmlV4Function(const QQmlV4Function &);
-    QQmlV4Function &operator=(const QQmlV4Function &);
-
-    QQmlV4Function(QV4::CallData *callData, QV4::Value *retVal, QV4::ExecutionEngine *e)
-        : callData(callData), retVal(retVal), e(e)
-    {
-        callData->thisObject = QV4::Encode::undefined();
-    }
-
-    QV4::CallData *callData;
-    QV4::Value *retVal;
-    QV4::ExecutionEngine *e;
-};
-
-class QObject;
-class QQmlEngine;
-class QNetworkAccessManager;
-class QQmlContextData;
-
-class Q_QML_PRIVATE_EXPORT QV8Engine
-{
-    friend class QJSEngine;
-public:
-//    static QJSEngine* get(QV8Engine* d) { Q_ASSERT(d); return d->q; }
-    static QV4::ExecutionEngine *getV4(QV8Engine *d) { return d->m_v4Engine; }
-
-    QV8Engine(QV4::ExecutionEngine *v4);
-    virtual ~QV8Engine();
-
-    // This enum should be in sync with QQmlEngine::ObjectOwnership
-    enum ObjectOwnership { CppOwnership, JavaScriptOwnership };
-
-    struct Deletable {
-        virtual ~Deletable() {}
-    };
-
-    void initQmlGlobalObject();
-    void setEngine(QQmlEngine *engine);
-    QQmlEngine *engine() { return m_engine; }
-    QQmlDelayedCallQueue *delayedCallQueue() { return &m_delayedCallQueue; }
-
-#if QT_CONFIG(qml_xml_http_request)
-    void *xmlHttpRequestData() const { return m_xmlHttpRequestData; }
-#endif
-
-    void freezeObject(const QV4::Value &value);
-
-#if QT_CONFIG(qml_network)
-    // Return the network access manager for this engine.  By default this returns the network
-    // access manager of the QQmlEngine.  It is overridden in the case of a threaded v8
-    // instance (like in WorkerScript).
-    virtual QNetworkAccessManager *networkAccessManager();
-#endif
-
-    // Return the list of illegal id names (the names of the properties on the global object)
-    const QSet<QString> &illegalNames() const;
-
-    static QMutex *registrationMutex();
-    static int registerExtension();
-
-    inline Deletable *extensionData(int) const;
-    void setExtensionData(int, Deletable *);
-
-public:
-    // used for console.time(), console.timeEnd()
-    void startTimer(const QString &timerName);
-    qint64 stopTimer(const QString &timerName, bool *wasRunning);
-
-    // used for console.count()
-    int consoleCountHelper(const QString &file, quint16 line, quint16 column);
-
-protected:
-    QQmlEngine *m_engine;
-    QQmlDelayedCallQueue m_delayedCallQueue;
-
-    QV4::ExecutionEngine *m_v4Engine;
-
-#if QT_CONFIG(qml_xml_http_request)
-    void *m_xmlHttpRequestData;
-#endif
-
-    QVector<Deletable *> m_extensionData;
-
-    QSet<QString> m_illegalNames;
-
-    QElapsedTimer m_time;
-    QHash<QString, qint64> m_startedTimers;
-
-    QHash<QString, quint32> m_consoleCount;
-
-    void initializeGlobal();
-
-private:
-    Q_DISABLE_COPY(QV8Engine)
-};
-
-inline QV8Engine::Deletable *QV8Engine::extensionData(int index) const
-{
-    if (index < m_extensionData.count())
-        return m_extensionData[index];
-    else
-        return nullptr;
-}
-
-
-QT_END_NAMESPACE
-
-#endif // QQMLV8ENGINE_P_H
diff --git a/src/qml/qml/v8/v8.pri b/src/qml/qml/v8/v8.pri
index 4592022939..fbcc47de0c 100644
--- a/src/qml/qml/v8/v8.pri
+++ b/src/qml/qml/v8/v8.pri
@@ -1,11 +1,9 @@
 HEADERS += \
-    $$PWD/qv8engine_p.h \
     $$PWD/qv4domerrors_p.h \
     $$PWD/qv4sqlerrors_p.h \
     $$PWD/qqmlbuiltinfunctions_p.h
 
 SOURCES += \
-    $$PWD/qv8engine.cpp \
     $$PWD/qv4domerrors.cpp \
     $$PWD/qv4sqlerrors.cpp \
     $$PWD/qqmlbuiltinfunctions.cpp
diff --git a/src/qml/qtqml.tracepoints b/src/qml/qtqml.tracepoints
new file mode 100644
index 0000000000..841748f201
--- /dev/null
+++ b/src/qml/qtqml.tracepoints
@@ -0,0 +1,14 @@
+{
+namespace QV4 {
+class ExecutionEngine;
+namespace CompiledData {
+class CompilationUnit;
+class Object;
+} // CompiledData
+} // QV4
+}
+
+QQmlObjectCreator_createInstance_entry(const QV4::CompiledData::CompilationUnit *compilationUnit, const QV4::CompiledData::Object *object, const QUrl &url)
+QQmlObjectCreator_createInstance_exit(const QString &typeName)
+QQmlV4_function_call_entry(const QV4::ExecutionEngine *engine, const QString &function, const QString &fileName, int line, int column)
+QQmlV4_function_call_exit()
diff --git a/src/qml/qtqmlglobal.h b/src/qml/qtqmlglobal.h
index a111f72e81..3e275c6359 100644
--- a/src/qml/qtqmlglobal.h
+++ b/src/qml/qtqmlglobal.h
@@ -54,6 +54,8 @@
 #  define QT_FEATURE_qml_debug -1
 #  define QT_FEATURE_qml_sequence_object 1
 #  define QT_FEATURE_qml_jit -1
+#  define QT_FEATURE_qml_worker_script -1
+#  define QT_FEATURE_qml_xml_http_request -1
 #endif
 
 QT_BEGIN_NAMESPACE
diff --git a/src/qml/types/qqmlbind.cpp b/src/qml/types/qqmlbind.cpp
index 513f7f2997..1ba015f796 100644
--- a/src/qml/types/qqmlbind.cpp
+++ b/src/qml/types/qqmlbind.cpp
@@ -43,6 +43,8 @@
 #include <private/qqmlproperty_p.h>
 #include <private/qqmlbinding_p.h>
 #include <private/qqmlmetatype_p.h>
+#include <private/qqmlvmemetaobject_p.h>
+#include <private/qv4persistent_p.h>
 
 #include <qqmlengine.h>
 #include <qqmlcontext.h>
@@ -60,7 +62,21 @@ QT_BEGIN_NAMESPACE
 class QQmlBindPrivate : public QObjectPrivate
 {
 public:
-    QQmlBindPrivate() : obj(nullptr), componentComplete(true), delayed(false), pendingEval(false) {}
+    QQmlBindPrivate()
+        : obj(nullptr)
+        , prevBind(QQmlAbstractBinding::Ptr())
+        , prevIsVariant(false)
+        , componentComplete(true)
+        , delayed(false)
+        , pendingEval(false)
+        , restoreBinding(true)
+#if QT_VERSION < QT_VERSION_CHECK(5, 15, 0)
+        , restoreValue(false)
+        , restoreModeExplicit(false)
+#else
+        , restoreValue(true)
+#endif
+    {}
     ~QQmlBindPrivate() { }
 
     QQmlNullableValue<bool> when;
@@ -69,11 +85,20 @@ public:
     QQmlNullableValue<QVariant> value;
     QQmlProperty prop;
     QQmlAbstractBinding::Ptr prevBind;
+    QV4::PersistentValue v4Value;
+    QVariant prevValue;
+    bool prevIsVariant:1;
     bool componentComplete:1;
     bool delayed:1;
     bool pendingEval:1;
+    bool restoreBinding:1;
+    bool restoreValue:1;
+#if QT_VERSION < QT_VERSION_CHECK(5, 15, 0)
+    bool restoreModeExplicit:1;
+#endif
 
     void validate(QObject *binding) const;
+    void clearPrev();
 };
 
 void QQmlBindPrivate::validate(QObject *binding) const
@@ -323,6 +348,57 @@ void QQmlBind::setDelayed(bool delayed)
         eval();
 }
 
+/*!
+    \qmlproperty enumeration QtQml::Binding::restoreMode
+    \since 5.14
+
+    This property can be used to describe if and how the original value should
+    be restored when the binding is disabled.
+
+    The possible values are:
+    \list
+    \li Binding.RestoreNone The original value is not restored at all
+    \li Binding.RestoreBinding The original value is restored if it was another
+        binding. In that case the old binding is in effect again.
+    \li Binding.RestoreValue The original value is restored if it was a plain
+        value rather than a binding.
+    \li Binding.RestoreBindingOrValue The original value is always restored.
+    \list
+
+    \warning The default value is Binding.RestoreBinding. This will change in
+    Qt 5.15 to Binding.RestoreBindingOrValue.
+
+    If you rely on any specific behavior regarding the restoration of plain
+    values when bindings get disabled you should migrate to explicitly set the
+    restoreMode.
+
+    Reliance on a restoreMode that doesn't restore the previous binding or value
+    for a specific property results in a run-time warning.
+*/
+QQmlBind::RestorationMode QQmlBind::restoreMode() const
+{
+    Q_D(const QQmlBind);
+    unsigned result = RestoreNone;
+    if (d->restoreValue)
+        result |= RestoreValue;
+    if (d->restoreBinding)
+        result |= RestoreBinding;
+    return RestorationMode(result);
+}
+
+void QQmlBind::setRestoreMode(RestorationMode newMode)
+{
+    Q_D(QQmlBind);
+    if (newMode != restoreMode()) {
+        d->restoreValue = (newMode & RestoreValue);
+        d->restoreBinding = (newMode & RestoreBinding);
+#if QT_VERSION < QT_VERSION_CHECK(5, 15, 0)
+        d->restoreModeExplicit = true;
+#endif
+        emit restoreModeChanged();
+    }
+}
+
 void QQmlBind::setTarget(const QQmlProperty &p)
 {
     Q_D(QQmlBind);
@@ -358,6 +434,14 @@ void QQmlBind::prepareEval()
     }
 }
 
+void QQmlBindPrivate::clearPrev()
+{
+    prevBind = nullptr;
+    v4Value.clear();
+    prevValue.clear();
+    prevIsVariant = false;
+}
+
 void QQmlBind::eval()
 {
     Q_D(QQmlBind);
@@ -369,16 +453,64 @@ void QQmlBind::eval()
         if (!d->when) {
             //restore any previous binding
             if (d->prevBind) {
-                QQmlAbstractBinding::Ptr p = d->prevBind;
-                d->prevBind = nullptr;
-                QQmlPropertyPrivate::setBinding(p.data());
+                if (d->restoreBinding) {
+                    QQmlAbstractBinding::Ptr p = d->prevBind;
+                    d->clearPrev(); // Do that before setBinding(), as setBinding() may recurse.
+                    QQmlPropertyPrivate::setBinding(p.data());
+                }
+            } else if (!d->v4Value.isEmpty()) {
+                if (d->restoreValue) {
+                    auto propPriv = QQmlPropertyPrivate::get(d->prop);
+                    QQmlVMEMetaObject *vmemo = QQmlVMEMetaObject::get(propPriv->object);
+                    Q_ASSERT(vmemo);
+                    vmemo->setVMEProperty(propPriv->core.coreIndex(), *d->v4Value.valueRef());
+                    d->clearPrev();
+#if QT_VERSION < QT_VERSION_CHECK(5, 15, 0)
+                } else if (!d->restoreModeExplicit) {
+                    qmlWarning(this)
+                            << "Not restoring previous value because restoreMode has not been set."
+                            << "This behavior is deprecated."
+                            << "In Qt < 5.15 the default is Binding.RestoreBinding."
+                            << "In Qt >= 5.15 the default is Binding.RestoreBindingOrValue.";
+#endif
+                }
+            } else if (d->prevIsVariant) {
+                if (d->restoreValue) {
+                    d->prop.write(d->prevValue);
+                    d->clearPrev();
+#if QT_VERSION < QT_VERSION_CHECK(5, 15, 0)
+                } else if (!d->restoreModeExplicit) {
+                    qmlWarning(this)
+                            << "Not restoring previous value because restoreMode has not been set."
+                            << "This behavior is deprecated."
+                            << "In Qt < 5.15 the default is Binding.RestoreBinding."
+                            << "In Qt >= 5.15 the default is Binding.RestoreBindingOrValue.";
+#endif
+                }
             }
             return;
         }
 
         //save any set binding for restoration
-        if (!d->prevBind)
+        if (!d->prevBind && d->v4Value.isEmpty() && !d->prevIsVariant) {
+            // try binding first
             d->prevBind = QQmlPropertyPrivate::binding(d->prop);
+
+            if (!d->prevBind) { // nope, try a V4 value next
+                auto propPriv = QQmlPropertyPrivate::get(d->prop);
+                auto propData = propPriv->core;
+                if (!propPriv->valueTypeData.isValid() && propData.isVarProperty()) {
+                    QQmlVMEMetaObject *vmemo = QQmlVMEMetaObject::get(propPriv->object);
+                    Q_ASSERT(vmemo);
+                    auto retVal = vmemo->vmeProperty(propData.coreIndex());
+                    d->v4Value = QV4::PersistentValue(vmemo->engine, retVal);
+                } else { // nope, use the meta object to get a QVariant
+                    d->prevValue = d->prop.read();
+                    d->prevIsVariant = true;
+                }
+            }
+        }
+
         QQmlPropertyPrivate::removeBinding(d->prop);
     }
 
diff --git a/src/qml/types/qqmlbind_p.h b/src/qml/types/qqmlbind_p.h
index 5bf9ef85c6..22007a3d25 100644
--- a/src/qml/types/qqmlbind_p.h
+++ b/src/qml/types/qqmlbind_p.h
@@ -60,6 +60,15 @@ QT_BEGIN_NAMESPACE
 class QQmlBindPrivate;
 class Q_AUTOTEST_EXPORT QQmlBind : public QObject, public QQmlPropertyValueSource, public QQmlParserStatus
 {
+public:
+    enum RestorationMode {
+        RestoreNone    = 0x0,
+        RestoreBinding = 0x1,
+        RestoreValue   = 0x2,
+        RestoreBindingOrValue = RestoreBinding | RestoreValue
+    };
+
+private:
     Q_OBJECT
     Q_DECLARE_PRIVATE(QQmlBind)
     Q_INTERFACES(QQmlParserStatus)
@@ -69,6 +78,9 @@ class Q_AUTOTEST_EXPORT QQmlBind : public QObject, public QQmlPropertyValueSourc
     Q_PROPERTY(QVariant value READ value WRITE setValue)
     Q_PROPERTY(bool when READ when WRITE setWhen)
     Q_PROPERTY(bool delayed READ delayed WRITE setDelayed REVISION 8)
+    Q_PROPERTY(RestorationMode restoreMode READ restoreMode WRITE setRestoreMode
+               NOTIFY restoreModeChanged REVISION 14)
+    Q_ENUM(RestorationMode)
 
 public:
     QQmlBind(QObject *parent=nullptr);
@@ -89,6 +101,12 @@ public:
     bool delayed() const;
     void setDelayed(bool);
 
+    RestorationMode restoreMode() const;
+    void setRestoreMode(RestorationMode);
+
+Q_SIGNALS:
+    void restoreModeChanged();
+
 protected:
     void setTarget(const QQmlProperty &) override;
     void classBegin() override;
diff --git a/src/qml/types/qqmlconnections.cpp b/src/qml/types/qqmlconnections.cpp
index f601087690..8ec754a9df 100644
--- a/src/qml/types/qqmlconnections.cpp
+++ b/src/qml/types/qqmlconnections.cpp
@@ -66,7 +66,7 @@ public:
     bool ignoreUnknownSignals;
     bool componentcomplete;
 
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> compilationUnit;
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> compilationUnit;
     QList<const QV4::CompiledData::Binding *> bindings;
 };
 
@@ -231,7 +231,7 @@ void QQmlConnections::setIgnoreUnknownSignals(bool ignore)
     d->ignoreUnknownSignals = ignore;
 }
 
-void QQmlConnectionsParser::verifyBindings(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &props)
+void QQmlConnectionsParser::verifyBindings(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &props)
 {
     for (int ii = 0; ii < props.count(); ++ii) {
         const QV4::CompiledData::Binding *binding = props.at(ii);
@@ -256,7 +256,7 @@ void QQmlConnectionsParser::verifyBindings(const QQmlRefPointer<QV4::CompiledDat
     }
 }
 
-void QQmlConnectionsParser::applyBindings(QObject *object, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings)
+void QQmlConnectionsParser::applyBindings(QObject *object, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings)
 {
     QQmlConnectionsPrivate *p =
         static_cast<QQmlConnectionsPrivate *>(QObjectPrivate::get(object));
diff --git a/src/qml/types/qqmlconnections_p.h b/src/qml/types/qqmlconnections_p.h
index bd03d7e152..f6ad1eb46c 100644
--- a/src/qml/types/qqmlconnections_p.h
+++ b/src/qml/types/qqmlconnections_p.h
@@ -98,8 +98,8 @@ private:
 class QQmlConnectionsParser : public QQmlCustomParser
 {
 public:
-    void verifyBindings(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &props) override;
-    void applyBindings(QObject *object, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings) override;
+    void verifyBindings(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &props) override;
+    void applyBindings(QObject *object, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings) override;
 };
 
 
diff --git a/src/qml/types/types.pri b/src/qml/types/types.pri
index ba11271d66..c50273071b 100644
--- a/src/qml/types/types.pri
+++ b/src/qml/types/types.pri
@@ -8,13 +8,6 @@ HEADERS += \
     $$PWD/qqmlconnections_p.h \
     $$PWD/qqmlmodelindexvaluetype_p.h
 
-qtConfig(qml-worker-script) {
-    SOURCES += \
-        $$PWD/qquickworkerscript.cpp
-    HEADERS += \
-        $$PWD/qquickworkerscript_p.h
-}
-
 qtConfig(qml-animation) {
     SOURCES += \
         $$PWD/qqmltimer.cpp
diff --git a/src/qmlmodels/configure.json b/src/qmlmodels/configure.json
index 2aa8a50e69..bfe7d538ec 100644
--- a/src/qmlmodels/configure.json
+++ b/src/qmlmodels/configure.json
@@ -6,6 +6,12 @@
     ],
 
     "features": {
+        "qml-object-model" : {
+            "label": "QML list model",
+            "purpose": "Provides the ObjectModel and Instantiator QML types.",
+            "section": "QML",
+            "output": [ "privateFeature" ]
+        },
         "qml-list-model": {
             "label": "QML list model",
             "purpose": "Provides the ListModel QML type.",
@@ -16,6 +22,13 @@
             "label": "QML delegate model",
             "purpose": "Provides the DelegateModel QML type.",
             "section": "QML",
+            "condition": "features.qml-object-model",
+            "output": [ "privateFeature" ]
+        },
+        "qml-table-model": {
+            "label": "QML table model",
+            "purpose": "Provides the TableModel QML type.",
+            "section": "QML",
             "output": [ "privateFeature" ]
         }
     },
diff --git a/src/qmlmodels/qmlmodels.pro b/src/qmlmodels/qmlmodels.pro
index 84f87f8bb1..7d1d9bdf67 100644
--- a/src/qmlmodels/qmlmodels.pro
+++ b/src/qmlmodels/qmlmodels.pro
@@ -5,30 +5,36 @@ DEFINES += QT_NO_URL_CAST_FROM_STRING QT_NO_INTEGER_EVENT_COORDINATES QT_NO_FORE
 
 HEADERS += \
     $$PWD/qqmlchangeset_p.h \
-    $$PWD/qqmlinstantiator_p.h \
-    $$PWD/qqmlinstantiator_p_p.h \
-    $$PWD/qqmllistaccessor_p.h \
-    $$PWD/qqmllistcompositor_p.h \
     $$PWD/qqmlmodelsmodule_p.h \
-    $$PWD/qqmlobjectmodel_p.h \
-    $$PWD/qqmltableinstancemodel_p.h \
-    $$PWD/qqmltablemodel_p.h \
-    $$PWD/qqmltablemodelcolumn_p.h \
-    $$PWD/qquickpackage_p.h \
     $$PWD/qtqmlmodelsglobal_p.h \
-    $$PWD/qtqmlmodelsglobal.h \
+    $$PWD/qtqmlmodelsglobal.h
 
 SOURCES += \
     $$PWD/qqmlchangeset.cpp \
-    $$PWD/qqmlinstantiator.cpp \
-    $$PWD/qqmllistaccessor.cpp \
-    $$PWD/qqmllistcompositor.cpp \
-    $$PWD/qqmlmodelsmodule.cpp \
-    $$PWD/qqmlobjectmodel.cpp \
-    $$PWD/qqmltableinstancemodel.cpp \
-    $$PWD/qqmltablemodel.cpp \
-    $$PWD/qqmltablemodelcolumn.cpp \
-    $$PWD/qquickpackage.cpp
+    $$PWD/qqmlmodelsmodule.cpp
+
+qtConfig(qml-object-model) {
+    SOURCES += \
+        $$PWD/qqmlinstantiator.cpp \
+        $$PWD/qqmlobjectmodel.cpp
+
+    HEADERS += \
+        $$PWD/qqmlinstantiator_p.h \
+        $$PWD/qqmlinstantiator_p_p.h \
+        $$PWD/qqmlobjectmodel_p.h
+}
+
+qtConfig(qml-table-model) {
+    SOURCES += \
+        $$PWD/qqmltableinstancemodel.cpp \
+        $$PWD/qqmltablemodel.cpp \
+        $$PWD/qqmltablemodelcolumn.cpp
+
+    HEADERS += \
+        $$PWD/qqmltableinstancemodel_p.h \
+        $$PWD/qqmltablemodel_p.h \
+        $$PWD/qqmltablemodelcolumn_p.h
+}
 
 qtConfig(qml-list-model) {
     SOURCES += \
@@ -45,13 +51,19 @@ qtConfig(qml-delegate-model) {
     SOURCES += \
         $$PWD/qqmladaptormodel.cpp \
         $$PWD/qqmldelegatemodel.cpp \
-        $$PWD/qqmldelegatecomponent.cpp
+        $$PWD/qqmldelegatecomponent.cpp \
+        $$PWD/qqmllistaccessor.cpp \
+        $$PWD/qqmllistcompositor.cpp \
+        $$PWD/qquickpackage.cpp
 
     HEADERS += \
         $$PWD/qqmladaptormodel_p.h \
         $$PWD/qqmldelegatemodel_p.h \
         $$PWD/qqmldelegatemodel_p_p.h \
-        $$PWD/qqmldelegatecomponent_p.h
+        $$PWD/qqmldelegatecomponent_p.h \
+        $$PWD/qqmllistaccessor_p.h \
+        $$PWD/qqmllistcompositor_p.h \
+        $$PWD/qquickpackage_p.h
 }
 
 load(qt_module)
diff --git a/src/qmlmodels/qqmladaptormodel.cpp b/src/qmlmodels/qqmladaptormodel.cpp
index f991ae0a69..0bc67e1aad 100644
--- a/src/qmlmodels/qqmladaptormodel.cpp
+++ b/src/qmlmodels/qqmladaptormodel.cpp
@@ -48,7 +48,7 @@
 
 QT_BEGIN_NAMESPACE
 
-class QQmlAdaptorModelEngineData : public QV8Engine::Deletable
+class QQmlAdaptorModelEngineData : public QV4::ExecutionEngine::Deletable
 {
 public:
     QQmlAdaptorModelEngineData(QV4::ExecutionEngine *v4);
diff --git a/src/qmlmodels/qqmldelegatemodel.cpp b/src/qmlmodels/qqmldelegatemodel.cpp
index 742c164508..2216e5fb50 100644
--- a/src/qmlmodels/qqmldelegatemodel.cpp
+++ b/src/qmlmodels/qqmldelegatemodel.cpp
@@ -123,7 +123,7 @@ DEFINE_OBJECT_VTABLE(QV4::DelegateModelGroupFunction);
 
 
 
-class QQmlDelegateModelEngineData : public QV8Engine::Deletable
+class QQmlDelegateModelEngineData : public QV4::ExecutionEngine::Deletable
 {
 public:
     QQmlDelegateModelEngineData(QV4::ExecutionEngine *v4);
diff --git a/src/qmlmodels/qqmlinstantiator_p.h b/src/qmlmodels/qqmlinstantiator_p.h
index 8b00a1e033..87accc304f 100644
--- a/src/qmlmodels/qqmlinstantiator_p.h
+++ b/src/qmlmodels/qqmlinstantiator_p.h
@@ -55,6 +55,8 @@
 #include <QtQml/qqmlparserstatus.h>
 #include <QtQmlModels/private/qtqmlmodelsglobal_p.h>
 
+QT_REQUIRE_CONFIG(qml_object_model);
+
 QT_BEGIN_NAMESPACE
 
 class QQmlInstantiatorPrivate;
diff --git a/src/qmlmodels/qqmlinstantiator_p_p.h b/src/qmlmodels/qqmlinstantiator_p_p.h
index bf153d8723..33cc2613e5 100644
--- a/src/qmlmodels/qqmlinstantiator_p_p.h
+++ b/src/qmlmodels/qqmlinstantiator_p_p.h
@@ -57,6 +57,8 @@
 #include <private/qqmlchangeset_p.h>
 #include <private/qqmlobjectmodel_p.h>
 
+QT_REQUIRE_CONFIG(qml_object_model);
+
 QT_BEGIN_NAMESPACE
 
 class Q_QMLMODELS_PRIVATE_EXPORT QQmlInstantiatorPrivate : public QObjectPrivate
diff --git a/src/qmlmodels/qqmllistmodel.cpp b/src/qmlmodels/qqmllistmodel.cpp
index 5b5bcd8464..c1684d955c 100644
--- a/src/qmlmodels/qqmllistmodel.cpp
+++ b/src/qmlmodels/qqmllistmodel.cpp
@@ -314,7 +314,7 @@ QString StringOrTranslation::toString(const QQmlListModel *owner) const
     }
     if (!owner)
         return QString();
-    return d.asT2()->valueAsString(owner->m_compilationUnit.data());
+    return owner->m_compilationUnit->bindingValueAsString(d.asT2());
 }
 
 QString StringOrTranslation::asString() const
@@ -2676,7 +2676,7 @@ void QQmlListModel::sync()
     qmlWarning(this) << "List sync() can only be called from a WorkerScript";
 }
 
-bool QQmlListModelParser::verifyProperty(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QV4::CompiledData::Binding *binding)
+bool QQmlListModelParser::verifyProperty(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QV4::CompiledData::Binding *binding)
 {
     if (binding->type >= QV4::CompiledData::Binding::Type_Object) {
         const quint32 targetObjectIndex = binding->value.objectIndex;
@@ -2707,7 +2707,7 @@ bool QQmlListModelParser::verifyProperty(const QQmlRefPointer<QV4::CompiledData:
                 return false;
         }
     } else if (binding->type == QV4::CompiledData::Binding::Type_Script) {
-        QString scriptStr = binding->valueAsScriptString(compilationUnit.data());
+        QString scriptStr = compilationUnit->bindingValueAsScriptString(binding);
         if (!binding->isFunctionExpression() && !definesEmptyList(scriptStr)) {
             QByteArray script = scriptStr.toUtf8();
             bool ok;
@@ -2722,7 +2722,9 @@ bool QQmlListModelParser::verifyProperty(const QQmlRefPointer<QV4::CompiledData:
     return true;
 }
 
-bool QQmlListModelParser::applyProperty(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QV4::CompiledData::Binding *binding, ListModel *model, int outterElementIndex)
+bool QQmlListModelParser::applyProperty(
+        const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit,
+        const QV4::CompiledData::Binding *binding, ListModel *model, int outterElementIndex)
 {
     const QString elementName = compilationUnit->stringAt(binding->propertyNameIndex);
 
@@ -2759,15 +2761,15 @@ bool QQmlListModelParser::applyProperty(const QQmlRefPointer<QV4::CompiledData::
         if (binding->isTranslationBinding()) {
             value = QVariant::fromValue<const QV4::CompiledData::Binding*>(binding);
         } else if (binding->evaluatesToString()) {
-            value = binding->valueAsString(compilationUnit.data());
+            value = compilationUnit->bindingValueAsString(binding);
         } else if (binding->type == QV4::CompiledData::Binding::Type_Number) {
-            value = binding->valueAsNumber(compilationUnit->constants);
+            value = compilationUnit->bindingValueAsNumber(binding);
         } else if (binding->type == QV4::CompiledData::Binding::Type_Boolean) {
             value = binding->valueAsBoolean();
         } else if (binding->type == QV4::CompiledData::Binding::Type_Null) {
             value = QVariant::fromValue(nullptr);
         } else if (binding->type == QV4::CompiledData::Binding::Type_Script) {
-            QString scriptStr = binding->valueAsScriptString(compilationUnit.data());
+            QString scriptStr = compilationUnit->bindingValueAsScriptString(binding);
             if (definesEmptyList(scriptStr)) {
                 const ListLayout::Role &role = model->getOrCreateListRole(elementName);
                 ListModel *emptyModel = new ListModel(role.subLayout, nullptr);
@@ -2802,7 +2804,7 @@ bool QQmlListModelParser::applyProperty(const QQmlRefPointer<QV4::CompiledData::
     return roleSet;
 }
 
-void QQmlListModelParser::verifyBindings(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings)
+void QQmlListModelParser::verifyBindings(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings)
 {
     listElementTypeName = QString(); // unknown
 
@@ -2817,7 +2819,7 @@ void QQmlListModelParser::verifyBindings(const QQmlRefPointer<QV4::CompiledData:
     }
 }
 
-void QQmlListModelParser::applyBindings(QObject *obj, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings)
+void QQmlListModelParser::applyBindings(QObject *obj, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings)
 {
     QQmlListModel *rv = static_cast<QQmlListModel *>(obj);
 
diff --git a/src/qmlmodels/qqmllistmodel_p.h b/src/qmlmodels/qqmllistmodel_p.h
index 4aabd790a5..10d67c1c6f 100644
--- a/src/qmlmodels/qqmllistmodel_p.h
+++ b/src/qmlmodels/qqmllistmodel_p.h
@@ -137,7 +137,7 @@ private:
 
     mutable QQmlListModelWorkerAgent *m_agent;
     mutable QV4::ExecutionEngine *m_engine;
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> m_compilationUnit;
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> m_compilationUnit;
     bool m_mainThread;
     bool m_primary;
 
@@ -188,13 +188,13 @@ public:
 
     QQmlListModelParser() : QQmlCustomParser(QQmlCustomParser::AcceptsSignalHandlers) {}
 
-    void verifyBindings(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings) override;
-    void applyBindings(QObject *obj, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings) override;
+    void verifyBindings(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings) override;
+    void applyBindings(QObject *obj, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings) override;
 
 private:
-    bool verifyProperty(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QV4::CompiledData::Binding *binding);
+    bool verifyProperty(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QV4::CompiledData::Binding *binding);
     // returns true if a role was set
-    bool applyProperty(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QV4::CompiledData::Binding *binding, ListModel *model, int outterElementIndex);
+    bool applyProperty(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QV4::CompiledData::Binding *binding, ListModel *model, int outterElementIndex);
 
     static bool definesEmptyList(const QString &);
 
diff --git a/src/qmlmodels/qqmllistmodelworkeragent_p.h b/src/qmlmodels/qqmllistmodelworkeragent_p.h
index f79c0c557a..1ef27cea3f 100644
--- a/src/qmlmodels/qqmllistmodelworkeragent_p.h
+++ b/src/qmlmodels/qqmllistmodelworkeragent_p.h
@@ -57,7 +57,7 @@
 #include <QMutex>
 #include <QWaitCondition>
 
-#include <private/qv8engine_p.h>
+#include <private/qv4engine_p.h>
 
 QT_REQUIRE_CONFIG(qml_list_model);
 
diff --git a/src/qmlmodels/qqmlmodelsmodule.cpp b/src/qmlmodels/qqmlmodelsmodule.cpp
index 989fec9b7d..2db5dd834f 100644
--- a/src/qmlmodels/qqmlmodelsmodule.cpp
+++ b/src/qmlmodels/qqmlmodelsmodule.cpp
@@ -39,19 +39,26 @@
 
 #include "qqmlmodelsmodule_p.h"
 #include <private/qtqmlmodelsglobal_p.h>
+
+#if QT_CONFIG(itemmodel)
 #include <QtCore/qitemselectionmodel.h>
+#endif
 #if QT_CONFIG(qml_list_model)
 #include <private/qqmllistmodel_p.h>
 #endif
 #if QT_CONFIG(qml_delegate_model)
 #include <private/qqmldelegatemodel_p.h>
 #include <private/qqmldelegatecomponent_p.h>
+#include <private/qquickpackage_p.h>
 #endif
+#if QT_CONFIG(qml_object_model)
 #include <private/qqmlobjectmodel_p.h>
+#include <private/qqmlinstantiator_p.h>
+#endif
+#if QT_CONFIG(qml_table_model)
 #include <private/qqmltablemodel_p.h>
 #include <private/qqmltablemodelcolumn_p.h>
-#include <private/qqmlinstantiator_p.h>
-#include <private/qquickpackage_p.h>
+#endif
 
 QT_BEGIN_NAMESPACE
 
@@ -60,8 +67,10 @@ QT_BEGIN_NAMESPACE
 void QQmlModelsModule::registerQmlTypes()
 {
     // Don't add anything here. These are only for backwards compatibility.
+#if QT_CONFIG(qml_object_model)
     qmlRegisterType<QQmlInstantiator>("QtQml", 2, 1, "Instantiator"); // Only available in >= 2.1
     qmlRegisterType<QQmlInstanceModel>();
+#endif
 }
 
 void QQmlModelsModule::registerQuickTypes()
@@ -70,18 +79,20 @@ void QQmlModelsModule::registerQuickTypes()
 
     const char uri[] = "QtQuick";
 
+#if QT_CONFIG(qml_object_model)
     qmlRegisterType<QQmlInstantiator>(uri, 2, 1, "Instantiator");
     qmlRegisterType<QQmlInstanceModel>();
+    qmlRegisterType<QQmlObjectModel>(uri, 2, 0, "VisualItemModel");
+#endif
 #if QT_CONFIG(qml_list_model)
     qmlRegisterType<QQmlListElement>(uri, 2, 0, "ListElement");
     qmlRegisterCustomType<QQmlListModel>(uri, 2, 0, "ListModel", new QQmlListModelParser);
 #endif
-    qmlRegisterType<QQuickPackage>(uri, 2, 0, "Package");
 #if QT_CONFIG(qml_delegate_model)
     qmlRegisterType<QQmlDelegateModel>(uri, 2, 0, "VisualDataModel");
     qmlRegisterType<QQmlDelegateModelGroup>(uri, 2, 0, "VisualDataGroup");
+    qmlRegisterType<QQuickPackage>(uri, 2, 0, "Package");
 #endif
-    qmlRegisterType<QQmlObjectModel>(uri, 2, 0, "VisualItemModel");
 }
 
 #endif // QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
@@ -97,15 +108,17 @@ void QQmlModelsModule::defineModule()
 #if QT_CONFIG(qml_delegate_model)
     qmlRegisterType<QQmlDelegateModel>(uri, 2, 1, "DelegateModel");
     qmlRegisterType<QQmlDelegateModelGroup>(uri, 2, 1, "DelegateModelGroup");
+    qmlRegisterType<QQuickPackage>(uri, 2, 14, "Package");
 #endif
+#if QT_CONFIG(qml_object_model)
     qmlRegisterType<QQmlObjectModel>(uri, 2, 1, "ObjectModel");
     qmlRegisterType<QQmlObjectModel,3>(uri, 2, 3, "ObjectModel");
-
-    qmlRegisterType<QItemSelectionModel>(uri, 2, 2, "ItemSelectionModel");
-
-    qmlRegisterType<QQuickPackage>(uri, 2, 14, "Package");
     qmlRegisterType<QQmlInstantiator>(uri, 2, 14, "Instantiator");
     qmlRegisterType<QQmlInstanceModel>();
+#endif
+#if QT_CONFIG(itemmodel)
+    qmlRegisterType<QItemSelectionModel>(uri, 2, 2, "ItemSelectionModel");
+#endif
 }
 
 void QQmlModelsModule::defineLabsModule()
@@ -117,8 +130,10 @@ void QQmlModelsModule::defineLabsModule()
     qmlRegisterType<QQmlDelegateChooser>(uri, 1, 0, "DelegateChooser");
     qmlRegisterType<QQmlDelegateChoice>(uri, 1, 0, "DelegateChoice");
 #endif
+#if QT_CONFIG(qml_table_model)
     qmlRegisterType<QQmlTableModel>(uri, 1, 0, "TableModel");
     qmlRegisterType<QQmlTableModelColumn>(uri, 1, 0, "TableModelColumn");
+#endif
 }
 
 QT_END_NAMESPACE
diff --git a/src/qmlmodels/qqmlobjectmodel_p.h b/src/qmlmodels/qqmlobjectmodel_p.h
index 99bfd86269..78a5615ae2 100644
--- a/src/qmlmodels/qqmlobjectmodel_p.h
+++ b/src/qmlmodels/qqmlobjectmodel_p.h
@@ -56,6 +56,8 @@
 #include <QtQml/qqml.h>
 #include <QtCore/qobject.h>
 
+QT_REQUIRE_CONFIG(qml_object_model);
+
 QT_BEGIN_NAMESPACE
 
 class QObject;
diff --git a/src/qmlmodels/qqmltableinstancemodel_p.h b/src/qmlmodels/qqmltableinstancemodel_p.h
index 20331df5cc..ce5a37bc98 100644
--- a/src/qmlmodels/qqmltableinstancemodel_p.h
+++ b/src/qmlmodels/qqmltableinstancemodel_p.h
@@ -54,6 +54,8 @@
 #include <QtQmlModels/private/qqmldelegatemodel_p.h>
 #include <QtQmlModels/private/qqmldelegatemodel_p_p.h>
 
+QT_REQUIRE_CONFIG(qml_table_model);
+
 QT_BEGIN_NAMESPACE
 
 class QQmlTableInstanceModel;
diff --git a/src/qmlmodels/qqmltablemodel_p.h b/src/qmlmodels/qqmltablemodel_p.h
index 114b162e5c..b3c0cc2848 100644
--- a/src/qmlmodels/qqmltablemodel_p.h
+++ b/src/qmlmodels/qqmltablemodel_p.h
@@ -59,6 +59,8 @@
 #include <QtQml/QJSValue>
 #include <QtQml/QQmlListProperty>
 
+QT_REQUIRE_CONFIG(qml_table_model);
+
 QT_BEGIN_NAMESPACE
 
 class Q_QMLMODELS_PRIVATE_EXPORT QQmlTableModel : public QAbstractTableModel, public QQmlParserStatus
diff --git a/src/qmlmodels/qqmltablemodelcolumn_p.h b/src/qmlmodels/qqmltablemodelcolumn_p.h
index d125f8bb16..0b6478ce38 100644
--- a/src/qmlmodels/qqmltablemodelcolumn_p.h
+++ b/src/qmlmodels/qqmltablemodelcolumn_p.h
@@ -56,6 +56,8 @@
 #include <QtQmlModels/private/qtqmlmodelsglobal_p.h>
 #include <QtQml/qjsvalue.h>
 
+QT_REQUIRE_CONFIG(qml_table_model);
+
 QT_BEGIN_NAMESPACE
 
 class Q_QMLMODELS_PRIVATE_EXPORT QQmlTableModelColumn : public QObject
diff --git a/src/qmlmodels/qquickpackage_p.h b/src/qmlmodels/qquickpackage_p.h
index 122c7fcb30..97f7818fee 100644
--- a/src/qmlmodels/qquickpackage_p.h
+++ b/src/qmlmodels/qquickpackage_p.h
@@ -52,6 +52,9 @@
 //
 
 #include <qqml.h>
+#include <QtQmlModels/private/qtqmlmodelsglobal_p.h>
+
+QT_REQUIRE_CONFIG(qml_delegate_model);
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/qmltest/quicktest.cpp b/src/qmltest/quicktest.cpp
index 9cddf61543..6aff7af0e7 100644
--- a/src/qmltest/quicktest.cpp
+++ b/src/qmltest/quicktest.cpp
@@ -70,6 +70,7 @@
 #include <QtQml/QQmlFileSelector>
 
 #include <private/qqmlcomponent_p.h>
+#include <private/qv4executablecompilationunit_p.h>
 
 #ifdef QT_QMLTEST_WITH_WIDGETS
 #include <QtWidgets/QApplication>
@@ -290,7 +291,8 @@ public:
         m_errors += component.errors();
 
         if (component.isReady()) {
-            QQmlRefPointer<CompilationUnit> rootCompilationUnit = QQmlComponentPrivate::get(&component)->compilationUnit;
+            QQmlRefPointer<QV4::ExecutableCompilationUnit> rootCompilationUnit
+                    = QQmlComponentPrivate::get(&component)->compilationUnit;
             TestCaseEnumerationResult result = enumerateTestCases(rootCompilationUnit.data());
             m_testCases = result.testCases + result.finalizedPartialTestCases();
             m_errors += result.errors;
@@ -330,7 +332,8 @@ private:
         }
     };
 
-    TestCaseEnumerationResult enumerateTestCases(CompilationUnit *compilationUnit, const Object *object = nullptr)
+    TestCaseEnumerationResult enumerateTestCases(QV4::ExecutableCompilationUnit *compilationUnit,
+                                                 const Object *object = nullptr)
     {
         QQmlType testCaseType;
         for (quint32 i = 0, count = compilationUnit->importCount(); i < count; ++i) {
@@ -353,7 +356,9 @@ private:
         if (!object) // Start at root of compilation unit if not enumerating a specific child
             object = compilationUnit->objectAt(0);
 
-        if (CompilationUnit *superTypeUnit = compilationUnit->resolvedTypes.value(object->inheritedTypeNameIndex)->compilationUnit.data()) {
+        if (QV4::ExecutableCompilationUnit *superTypeUnit
+            = compilationUnit->resolvedTypes.value(object->inheritedTypeNameIndex)
+                      ->compilationUnit.data()) {
             // We have a non-C++ super type, which could indicate we're a subtype of a TestCase
             if (testCaseType.isValid() && superTypeUnit->url() == testCaseType.sourceUrl())
                 result.isTestCase = true;
diff --git a/src/qmlworkerscript/qmlworkerscript.pro b/src/qmlworkerscript/qmlworkerscript.pro
new file mode 100644
index 0000000000..908caa4ed4
--- /dev/null
+++ b/src/qmlworkerscript/qmlworkerscript.pro
@@ -0,0 +1,20 @@
+TARGET = QtQmlWorkerScript
+QT = core-private qml-private
+
+DEFINES += QT_NO_URL_CAST_FROM_STRING QT_NO_INTEGER_EVENT_COORDINATES QT_NO_FOREACH
+
+HEADERS += \
+    qqmlworkerscriptmodule_p.h \
+    qquickworkerscript_p.h \
+    qtqmlworkerscriptglobal.h \
+    qtqmlworkerscriptglobal_p.h \
+    qv4serialize_p.h
+
+SOURCES += \
+    qqmlworkerscriptmodule.cpp \
+    qquickworkerscript.cpp \
+    qv4serialize.cpp
+
+include(../3rdparty/masm/masm-defs.pri)
+
+load(qt_module)
diff --git a/src/qmlworkerscript/qqmlworkerscriptmodule.cpp b/src/qmlworkerscript/qqmlworkerscriptmodule.cpp
new file mode 100644
index 0000000000..98e82dbeba
--- /dev/null
+++ b/src/qmlworkerscript/qqmlworkerscriptmodule.cpp
@@ -0,0 +1,62 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtQml module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qqmlworkerscriptmodule_p.h"
+#include "qquickworkerscript_p.h"
+
+QT_BEGIN_NAMESPACE
+
+#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
+
+void QQmlWorkerScriptModule::registerQuickTypes()
+{
+    // Don't add anything here. These are only for backwards compatibility.
+    const char uri[] = "QtQuick";
+    qmlRegisterType<QQuickWorkerScript>(uri, 2, 0, "WorkerScript");
+}
+
+#endif // QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
+
+void QQmlWorkerScriptModule::defineModule()
+{
+    const char uri[] = "QtQml.WorkerScript";
+    qmlRegisterType<QQuickWorkerScript>(uri, 2, 0, "WorkerScript");
+}
+
+QT_END_NAMESPACE
diff --git a/src/qmlworkerscript/qqmlworkerscriptmodule_p.h b/src/qmlworkerscript/qqmlworkerscriptmodule_p.h
new file mode 100644
index 0000000000..a2efb304c1
--- /dev/null
+++ b/src/qmlworkerscript/qqmlworkerscriptmodule_p.h
@@ -0,0 +1,69 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtQml module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QQMLWORKERSCRIPTMODULE_P_H
+#define QQMLWORKERSCRIPTMODULE_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <private/qtqmlworkerscriptglobal_p.h>
+
+QT_BEGIN_NAMESPACE
+
+class Q_QMLWORKERSCRIPT_PRIVATE_EXPORT QQmlWorkerScriptModule
+{
+public:
+#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
+    static void registerQuickTypes();
+#endif
+    static void defineModule();
+};
+
+QT_END_NAMESPACE
+
+#endif // QQMLWORKERSCRIPTMODULE_P_H
diff --git a/src/qml/types/qquickworkerscript.cpp b/src/qmlworkerscript/qquickworkerscript.cpp
index c081c9e7fc..4da1def5f5 100644
--- a/src/qml/types/qquickworkerscript.cpp
+++ b/src/qmlworkerscript/qquickworkerscript.cpp
@@ -37,7 +37,7 @@
 **
 ****************************************************************************/
 
-#include "qtqmlglobal_p.h"
+#include "qtqmlworkerscriptglobal_p.h"
 #include "qquickworkerscript_p.h"
 #include <private/qqmlengine_p.h>
 #include <private/qqmlexpression_p.h>
@@ -57,7 +57,6 @@
 #include "qqmlnetworkaccessmanagerfactory.h"
 #endif
 
-#include <private/qv8engine_p.h>
 #include <private/qv4serialize_p.h>
 
 #include <private/qv4value_p.h>
@@ -125,6 +124,15 @@ private:
     QQmlError m_error;
 };
 
+struct WorkerScript : public QV4::ExecutionEngine {
+    WorkerScript(int id, QQuickWorkerScriptEnginePrivate *parent);
+
+    QQuickWorkerScriptEnginePrivate *p = nullptr;
+    QUrl source;
+    QQuickWorkerScript *owner = nullptr;
+    int id = -1;
+};
+
 class QQuickWorkerScriptEnginePrivate : public QObject
 {
     Q_OBJECT
@@ -140,23 +148,6 @@ public:
     QMutex m_lock;
     QWaitCondition m_wait;
 
-    struct WorkerScript : public QV8Engine {
-        WorkerScript(int id, QQuickWorkerScriptEnginePrivate *parent);
-        ~WorkerScript() override;
-
-#if QT_CONFIG(qml_network)
-        QNetworkAccessManager *networkAccessManager() override;
-#endif
-
-        QQuickWorkerScriptEnginePrivate *p = nullptr;
-        QUrl source;
-        QQuickWorkerScript *owner = nullptr;
-#if QT_CONFIG(qml_network)
-        QScopedPointer<QNetworkAccessManager> accessManager;
-#endif
-        int id = -1;
-    };
-
     QHash<int, WorkerScript *> workers;
     QV4::ReturnedValue getWorker(WorkerScript *);
 
@@ -185,7 +176,7 @@ QV4::ReturnedValue QQuickWorkerScriptEnginePrivate::method_sendMessage(const QV4
                                                                        const QV4::Value *, const QV4::Value *argv, int argc)
 {
     QV4::Scope scope(b);
-    WorkerScript *script = static_cast<WorkerScript *>(scope.engine->v8Engine);
+    WorkerScript *script = static_cast<WorkerScript *>(scope.engine);
 
     QV4::ScopedValue v(scope, argc > 0 ? argv[0] : QV4::Value::undefinedValue());
     QByteArray data = QV4::Serialize::serialize(v, scope.engine);
@@ -230,21 +221,20 @@ void QQuickWorkerScriptEnginePrivate::processMessage(int id, const QByteArray &d
     if (!script)
         return;
 
-    QV4::ExecutionEngine *v4 = QV8Engine::getV4(script);
-    QV4::Scope scope(v4);
+    QV4::Scope scope(script);
     QV4::ScopedString v(scope);
-    QV4::ScopedObject worker(scope, v4->globalObject->get((v = v4->newString(QStringLiteral("WorkerScript")))));
+    QV4::ScopedObject worker(scope, script->globalObject->get((v = script->newString(QStringLiteral("WorkerScript")))));
     QV4::ScopedFunctionObject onmessage(scope);
     if (worker)
-        onmessage = worker->get((v = v4->newString(QStringLiteral("onMessage"))));
+        onmessage = worker->get((v = script->newString(QStringLiteral("onMessage"))));
 
     if (!onmessage)
         return;
 
-    QV4::ScopedValue value(scope, QV4::Serialize::deserialize(data, v4));
+    QV4::ScopedValue value(scope, QV4::Serialize::deserialize(data, script));
 
     QV4::JSCallData jsCallData(scope, 1);
-    *jsCallData->thisObject = v4->global();
+    *jsCallData->thisObject = script->global();
     jsCallData->args[0] = value;
     onmessage->call(jsCallData);
     if (scope.hasException()) {
@@ -264,35 +254,33 @@ void QQuickWorkerScriptEnginePrivate::processLoad(int id, const QUrl &url)
     if (!script)
         return;
 
-    QV4::ExecutionEngine *v4 = QV8Engine::getV4(script);
-
     script->source = url;
 
     if (fileName.endsWith(QLatin1String(".mjs"))) {
-        auto moduleUnit = v4->loadModule(url);
+        auto moduleUnit = script->loadModule(url);
         if (moduleUnit) {
-            if (moduleUnit->instantiate(v4))
+            if (moduleUnit->instantiate(script))
                 moduleUnit->evaluate();
         } else {
-            v4->throwError(QStringLiteral("Could not load module file"));
+            script->throwError(QStringLiteral("Could not load module file"));
         }
     } else {
         QString error;
-        QV4::Scope scope(v4);
+        QV4::Scope scope(script);
         QScopedPointer<QV4::Script> program;
-        program.reset(QV4::Script::createFromFileOrCache(v4, /*qmlContext*/nullptr, fileName, url, &error));
+        program.reset(QV4::Script::createFromFileOrCache(script, /*qmlContext*/nullptr, fileName, url, &error));
         if (program.isNull()) {
             if (!error.isEmpty())
                 qWarning().nospace() << error;
             return;
         }
 
-        if (!v4->hasException)
+        if (!script->hasException)
             program->run();
     }
 
-    if (v4->hasException) {
-        QQmlError error = v4->catchExceptionAsQmlError();
+    if (script->hasException) {
+        QQmlError error = script->catchExceptionAsQmlError();
         reportScriptException(script, error);
     }
 }
@@ -389,45 +377,22 @@ QQuickWorkerScriptEngine::~QQuickWorkerScriptEngine()
     d->deleteLater();
 }
 
-QQuickWorkerScriptEnginePrivate::WorkerScript::WorkerScript(int id, QQuickWorkerScriptEnginePrivate *parent)
-    : QV8Engine(new QV4::ExecutionEngine)
-    , p(parent)
+WorkerScript::WorkerScript(int id, QQuickWorkerScriptEnginePrivate *parent)
+    : p(parent)
     , id(id)
 {
-    m_v4Engine->v8Engine = this;
-
     initQmlGlobalObject();
 
-    QV4::Scope scope(m_v4Engine);
+    QV4::Scope scope(this);
     QV4::ScopedObject api(scope, scope.engine->newObject());
-    QV4::ScopedString name(scope, m_v4Engine->newString(QStringLiteral("sendMessage")));
-    QV4::ScopedValue sendMessage(scope, QV4::FunctionObject::createBuiltinFunction(m_v4Engine, name, method_sendMessage, 1));
+    QV4::ScopedString name(scope, newString(QStringLiteral("sendMessage")));
+    QV4::ScopedValue sendMessage(scope, QV4::FunctionObject::createBuiltinFunction(this, name, QQuickWorkerScriptEnginePrivate::method_sendMessage, 1));
     api->put(QV4::ScopedString(scope, scope.engine->newString(QStringLiteral("sendMessage"))), sendMessage);
-    m_v4Engine->globalObject->put(QV4::ScopedString(scope, scope.engine->newString(QStringLiteral("WorkerScript"))), api);
-}
-
-QQuickWorkerScriptEnginePrivate::WorkerScript::~WorkerScript()
-{
-    delete m_v4Engine;
-}
-
-#if QT_CONFIG(qml_network)
-QNetworkAccessManager *QQuickWorkerScriptEnginePrivate::WorkerScript::networkAccessManager()
-{
-    if (!accessManager) {
-        if (p->qmlengine && p->qmlengine->networkAccessManagerFactory()) {
-            accessManager.reset(p->qmlengine->networkAccessManagerFactory()->create(p));
-        } else {
-            accessManager.reset(new QNetworkAccessManager(p));
-        }
-    }
-    return accessManager.data();
+    globalObject->put(QV4::ScopedString(scope, scope.engine->newString(QStringLiteral("WorkerScript"))), api);
 }
-#endif
 
 int QQuickWorkerScriptEngine::registerWorkerScript(QQuickWorkerScript *owner)
 {
-    typedef QQuickWorkerScriptEnginePrivate::WorkerScript WorkerScript;
     WorkerScript *script = new WorkerScript(d->m_nextId++, d);
 
     script->owner = owner;
@@ -441,8 +406,7 @@ int QQuickWorkerScriptEngine::registerWorkerScript(QQuickWorkerScript *owner)
 
 void QQuickWorkerScriptEngine::removeWorkerScript(int id)
 {
-    QQuickWorkerScriptEnginePrivate::WorkerScript* script = d->workers.value(id);
-    if (script) {
+    if (WorkerScript *script = d->workers.value(id)) {
         script->owner = nullptr;
         QCoreApplication::postEvent(d, new WorkerRemoveEvent(id));
     }
@@ -618,7 +582,11 @@ QQuickWorkerScriptEngine *QQuickWorkerScript::engine()
             return nullptr;
         }
 
-        m_engine = QQmlEnginePrivate::get(engine)->getWorkerScriptEngine();
+        QQmlEnginePrivate *enginePrivate = QQmlEnginePrivate::get(engine);
+        if (enginePrivate->workerScriptEngine == nullptr)
+            enginePrivate->workerScriptEngine = new QQuickWorkerScriptEngine(engine);
+        m_engine = qobject_cast<QQuickWorkerScriptEngine *>(enginePrivate->workerScriptEngine);
+        Q_ASSERT(m_engine);
         m_scriptId = m_engine->registerWorkerScript(this);
 
         if (m_source.isValid())
diff --git a/src/qml/types/qquickworkerscript_p.h b/src/qmlworkerscript/qquickworkerscript_p.h
index 87cf2e9754..87cf2e9754 100644
--- a/src/qml/types/qquickworkerscript_p.h
+++ b/src/qmlworkerscript/qquickworkerscript_p.h
diff --git a/src/qmlworkerscript/qtqmlworkerscriptglobal.h b/src/qmlworkerscript/qtqmlworkerscriptglobal.h
new file mode 100644
index 0000000000..be3ea4e12a
--- /dev/null
+++ b/src/qmlworkerscript/qtqmlworkerscriptglobal.h
@@ -0,0 +1,58 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtQml module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QTQMLWORKERSCRIPTGLOBAL_H
+#define QTQMLWORKERSCRIPTGLOBAL_H
+
+#include <QtQml/qtqmlglobal.h>
+
+QT_BEGIN_NAMESPACE
+
+#if !defined(QT_STATIC)
+#  if defined(QT_BUILD_QMLWORKERSCRIPT_LIB)
+#    define Q_QMLWORKERSCRIPT_EXPORT Q_DECL_EXPORT
+#  else
+#    define Q_QMLWORKERSCRIPT_EXPORT Q_DECL_IMPORT
+#  endif
+#else
+#  define Q_QMLWORKERSCRIPT_EXPORT
+#endif
+
+QT_END_NAMESPACE
+#endif // QTQMLWORKERSCRIPTGLOBAL_H
diff --git a/src/qmlworkerscript/qtqmlworkerscriptglobal_p.h b/src/qmlworkerscript/qtqmlworkerscriptglobal_p.h
new file mode 100644
index 0000000000..34236cd79e
--- /dev/null
+++ b/src/qmlworkerscript/qtqmlworkerscriptglobal_p.h
@@ -0,0 +1,60 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtQml module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QTQMLWORKERSCRIPTGLOBAL_P_H
+#define QTQMLWORKERSCRIPTGLOBAL_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <QtQml/private/qtqmlglobal_p.h>
+#include <QtQmlWorkerScript/qtqmlworkerscriptglobal.h>
+
+#define Q_QMLWORKERSCRIPT_PRIVATE_EXPORT Q_QMLWORKERSCRIPT_EXPORT
+#define Q_QMLWORKERSCRIPT_AUTOTEST_EXPORT Q_AUTOTEST_EXPORT
+
+#endif // QTQMLWORKERSCRIPTGLOBAL_P_H
diff --git a/src/qml/jsruntime/qv4serialize.cpp b/src/qmlworkerscript/qv4serialize.cpp
index a5e62d3e35..a5e62d3e35 100644
--- a/src/qml/jsruntime/qv4serialize.cpp
+++ b/src/qmlworkerscript/qv4serialize.cpp
diff --git a/src/qml/jsruntime/qv4serialize_p.h b/src/qmlworkerscript/qv4serialize_p.h
index c8700c3ca5..c8700c3ca5 100644
--- a/src/qml/jsruntime/qv4serialize_p.h
+++ b/src/qmlworkerscript/qv4serialize_p.h
diff --git a/src/quick/accessible/qaccessiblequickitem.cpp b/src/quick/accessible/qaccessiblequickitem.cpp
index 98e7663c96..b87203c3ef 100644
--- a/src/quick/accessible/qaccessiblequickitem.cpp
+++ b/src/quick/accessible/qaccessiblequickitem.cpp
@@ -382,6 +382,22 @@ QString QAccessibleQuickItem::text(QAccessible::Text textType) const
     return QString();
 }
 
+void QAccessibleQuickItem::setText(QAccessible::Text textType, const QString &text)
+{
+    if (role() != QAccessible::EditableText)
+        return;
+    if (textType != QAccessible::Value)
+        return;
+
+    if (QTextDocument *doc = textDocument()) {
+        doc->setPlainText(text);
+        return;
+    }
+    auto textPropertyName = "text";
+    if (object()->metaObject()->indexOfProperty(textPropertyName) >= 0)
+        object()->setProperty(textPropertyName, text);
+}
+
 void *QAccessibleQuickItem::interface_cast(QAccessible::InterfaceType t)
 {
     QAccessible::Role r = role();
diff --git a/src/quick/accessible/qaccessiblequickitem_p.h b/src/quick/accessible/qaccessiblequickitem_p.h
index 5375d37bf0..931e995f0f 100644
--- a/src/quick/accessible/qaccessiblequickitem_p.h
+++ b/src/quick/accessible/qaccessiblequickitem_p.h
@@ -83,6 +83,7 @@ public:
     QAccessible::State state() const override;
     QAccessible::Role role() const override;
     QString text(QAccessible::Text) const override;
+    void setText(QAccessible::Text, const QString &text) override;
 
     bool isAccessible() const;
 
diff --git a/src/quick/configure.json b/src/quick/configure.json
index 70fe6d2129..4098db87aa 100644
--- a/src/quick/configure.json
+++ b/src/quick/configure.json
@@ -113,6 +113,7 @@
             "label": "TableView item",
             "purpose": "Provides the TableView item.",
             "section": "Qt Quick",
+            "condition": "features.qml-table-model",
             "output": [
                 "privateFeature"
             ]
diff --git a/src/quick/designer/qquickdesignercustomparserobject.cpp b/src/quick/designer/qquickdesignercustomparserobject.cpp
index 50a8b6a25b..841aae5bc3 100644
--- a/src/quick/designer/qquickdesignercustomparserobject.cpp
+++ b/src/quick/designer/qquickdesignercustomparserobject.cpp
@@ -46,12 +46,12 @@ QQuickDesignerCustomParserObject::QQuickDesignerCustomParserObject()
 
 }
 
-void QQuickDesignerCustomParser::verifyBindings(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &)
+void QQuickDesignerCustomParser::verifyBindings(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &)
 {
     /* Nothing to do we accept anything */
 }
 
-void QQuickDesignerCustomParser::applyBindings(QObject *, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &)
+void QQuickDesignerCustomParser::applyBindings(QObject *, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &)
 {
     /* Nothing to do we accept anything */
 }
diff --git a/src/quick/designer/qquickdesignercustomparserobject_p.h b/src/quick/designer/qquickdesignercustomparserobject_p.h
index b38417d102..4da00ea841 100644
--- a/src/quick/designer/qquickdesignercustomparserobject_p.h
+++ b/src/quick/designer/qquickdesignercustomparserobject_p.h
@@ -70,8 +70,8 @@ public:
     QQuickDesignerCustomParser()
     : QQmlCustomParser(AcceptsAttachedProperties | AcceptsSignalHandlers) {}
 
-    void verifyBindings(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &props) override;
-    void applyBindings(QObject *obj, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings) override;
+    void verifyBindings(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &props) override;
+    void applyBindings(QObject *obj, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings) override;
 };
 
 QT_END_NAMESPACE
diff --git a/src/quick/doc/snippets/pointerHandlers/tapHandlerOnTapped.qml b/src/quick/doc/snippets/pointerHandlers/tapHandlerOnTapped.qml
new file mode 100644
index 0000000000..f556c238da
--- /dev/null
+++ b/src/quick/doc/snippets/pointerHandlers/tapHandlerOnTapped.qml
@@ -0,0 +1,64 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+//![0]
+import QtQuick 2.12
+
+Rectangle {
+    width: 100
+    height: 100
+
+    TapHandler {
+        acceptedButtons: Qt.LeftButton | Qt.RightButton
+        onTapped: console.log("tapped", eventPoint.event.device.name,
+                              "button", eventPoint.event.button,
+                              "@", eventPoint.scenePosition)
+    }
+}
+//![0]
diff --git a/src/quick/handlers/qquickdraghandler.cpp b/src/quick/handlers/qquickdraghandler.cpp
index 22fe3df4d0..61b66beff4 100644
--- a/src/quick/handlers/qquickdraghandler.cpp
+++ b/src/quick/handlers/qquickdraghandler.cpp
@@ -114,8 +114,14 @@ void QQuickDragHandler::onGrabChanged(QQuickPointerHandler *grabber, QQuickEvent
     QQuickMultiPointHandler::onGrabChanged(grabber, transition, point);
     if (grabber == this && transition == QQuickEventPoint::GrabExclusive && target()) {
         // In case the grab got handed over from another grabber, we might not get the Press.
-        if (!m_pressedInsideTarget) {
-            if (target() != parentItem())
+
+        auto isDescendant = [](QQuickItem *parent, QQuickItem *target) {
+            return (target != parent) && !target->isAncestorOf(parent);
+        };
+        if (m_snapMode == SnapAlways
+            || (m_snapMode == SnapIfPressedOutsideTarget && !m_pressedInsideTarget)
+            || (m_snapMode == SnapAuto && !m_pressedInsideTarget && isDescendant(parentItem(), target()))
+            ) {
                 m_pressTargetPos = QPointF(target()->width(), target()->height()) / 2;
         } else if (m_pressTargetPos.isNull()) {
             m_pressTargetPos = targetCentroidPosition();
@@ -123,6 +129,33 @@ void QQuickDragHandler::onGrabChanged(QQuickPointerHandler *grabber, QQuickEvent
     }
 }
 
+/*!
+    \qmlproperty enumeration QtQuick.DragHandler::snapMode
+
+    This property holds the snap mode.
+
+    The snap mode configures snapping of the \l target item's center to the event point.
+
+    Possible values:
+    \value DragHandler.SnapNever Never snap
+    \value DragHandler.SnapAuto The \l target snaps if the event point was pressed outside of the \l target
+                                item \e and the \l target is a descendant of \l parentItem (default)
+    \value DragHandler.SnapWhenPressedOutsideTarget The \l target snaps if the event point was pressed outside of the \l target
+    \value DragHandler.SnapAlways Always snap
+*/
+QQuickDragHandler::SnapMode QQuickDragHandler::snapMode() const
+{
+    return m_snapMode;
+}
+
+void QQuickDragHandler::setSnapMode(QQuickDragHandler::SnapMode mode)
+{
+    if (mode == m_snapMode)
+        return;
+    m_snapMode = mode;
+    emit snapModeChanged();
+}
+
 void QQuickDragHandler::onActiveChanged()
 {
     QQuickMultiPointHandler::onActiveChanged();
diff --git a/src/quick/handlers/qquickdraghandler_p.h b/src/quick/handlers/qquickdraghandler_p.h
index 748026488a..18c1fd841d 100644
--- a/src/quick/handlers/qquickdraghandler_p.h
+++ b/src/quick/handlers/qquickdraghandler_p.h
@@ -62,8 +62,17 @@ class Q_QUICK_PRIVATE_EXPORT QQuickDragHandler : public QQuickMultiPointHandler
     Q_PROPERTY(QQuickDragAxis * xAxis READ xAxis CONSTANT)
     Q_PROPERTY(QQuickDragAxis * yAxis READ yAxis CONSTANT)
     Q_PROPERTY(QVector2D translation READ translation NOTIFY translationChanged)
+    Q_PROPERTY(SnapMode snapMode READ snapMode WRITE setSnapMode NOTIFY snapModeChanged)
 
 public:
+    enum SnapMode {
+        NoSnap = 0,
+        SnapAuto,
+        SnapIfPressedOutsideTarget,
+        SnapAlways
+    };
+    Q_ENUM(SnapMode)
+
     explicit QQuickDragHandler(QQuickItem *parent = nullptr);
 
     void handlePointerEventImpl(QQuickPointerEvent *event) override;
@@ -73,11 +82,14 @@ public:
 
     QVector2D translation() const { return m_translation; }
     void setTranslation(const QVector2D &trans);
+    QQuickDragHandler::SnapMode snapMode() const;
+    void setSnapMode(QQuickDragHandler::SnapMode mode);
 
     void enforceConstraints();
 
 Q_SIGNALS:
     void translationChanged();
+    void snapModeChanged();
 
 protected:
     void onActiveChanged() override;
@@ -97,6 +109,7 @@ private:
 
     QQuickDragAxis m_xAxis;
     QQuickDragAxis m_yAxis;
+    QQuickDragHandler::SnapMode m_snapMode = SnapAuto;
     bool m_pressedInsideTarget = false;
 
     friend class QQuickDragAxis;
diff --git a/src/quick/handlers/qquicktaphandler.cpp b/src/quick/handlers/qquicktaphandler.cpp
index 081645da71..40a4813527 100644
--- a/src/quick/handlers/qquicktaphandler.cpp
+++ b/src/quick/handlers/qquicktaphandler.cpp
@@ -381,35 +381,50 @@ void QQuickTapHandler::updateTimeHeld()
 */
 
 /*!
-    \qmlsignal QtQuick::TapHandler::tapped
+    \qmlsignal QtQuick::TapHandler::tapped(EventPoint eventPoint)
 
     This signal is emitted each time the \c parent Item is tapped.
 
     That is, if you press and release a touchpoint or button within a time
     period less than \l longPressThreshold, while any movement does not exceed
     the drag threshold, then the \c tapped signal will be emitted at the time
-    of release.
+    of release.  The \c eventPoint signal parameter contains information
+    from the release event about the point that was tapped:
+
+    \snippet pointerHandlers/tapHandlerOnTapped.qml 0
+
+    \note At the time this signal is emitted, \l point has been reset
+    (all coordinates are \c 0).
 */
 
 /*!
-    \qmlsignal QtQuick::TapHandler::singleTapped
+    \qmlsignal QtQuick::TapHandler::singleTapped(EventPoint eventPoint)
     \since 5.11
 
     This signal is emitted when the \c parent Item is tapped once.
     After an amount of time greater than QStyleHints::mouseDoubleClickInterval,
     it can be tapped again; but if the time until the next tap is less,
-    \l tapCount will increase.
+    \l tapCount will increase. The \c eventPoint signal parameter contains
+    information from the release event about the point that was tapped.
+
+    \note At the time this signal is emitted, \l point has been reset
+    (all coordinates are \c 0).
 */
 
 /*!
-    \qmlsignal QtQuick::TapHandler::doubleTapped
+    \qmlsignal QtQuick::TapHandler::doubleTapped(EventPoint eventPoint)
     \since 5.11
 
     This signal is emitted when the \c parent Item is tapped twice within a
     short span of time (QStyleHints::mouseDoubleClickInterval) and distance
     (QPlatformTheme::MouseDoubleClickDistance or
     QPlatformTheme::TouchDoubleTapDistance). This signal always occurs after
-    \l singleTapped, \l tapped, and \l tapCountChanged.
+    \l singleTapped, \l tapped, and \l tapCountChanged. The \c eventPoint
+    signal parameter contains information from the release event about the
+    point that was tapped.
+
+    \note At the time this signal is emitted, \l point has been reset
+    (all coordinates are \c 0).
 */
 
 /*!
diff --git a/src/quick/items/context2d/qquickcontext2d.cpp b/src/quick/items/context2d/qquickcontext2d.cpp
index 58bc12a221..0f104a122f 100644
--- a/src/quick/items/context2d/qquickcontext2d.cpp
+++ b/src/quick/items/context2d/qquickcontext2d.cpp
@@ -473,7 +473,7 @@ static QFont qt_font_from_string(const QString& fontString, const QFont &current
     return newFont;
 }
 
-class QQuickContext2DEngineData : public QV8Engine::Deletable
+class QQuickContext2DEngineData : public QV4::ExecutionEngine::Deletable
 {
 public:
     QQuickContext2DEngineData(QV4::ExecutionEngine *engine);
@@ -2000,7 +2000,7 @@ QV4::ReturnedValue QQuickJSContext2D::method_set_miterLimit(const QV4::FunctionO
     \since QtQuick 2.11
     Returns an array of qreals representing the dash pattern of the line.
 
-    \sa setLineDash()
+    \sa setLineDash(), lineDashOffset
   */
 QV4::ReturnedValue QQuickJSContext2DPrototype::method_getLineDash(const QV4::FunctionObject *b, const QV4::Value *thisObject, const QV4::Value *, int)
 {
@@ -2022,7 +2022,7 @@ QV4::ReturnedValue QQuickJSContext2DPrototype::method_getLineDash(const QV4::Fun
 /*!
     \qmlmethod QtQuick::Context2D::setLineDash(array pattern)
     \since QtQuick 2.11
-    Sets the dash pattern to the given pattern
+    Sets the dash pattern to the given pattern.
 
     \a pattern a list of numbers that specifies distances to alternately draw a line and a gap.
 
@@ -2041,7 +2041,7 @@ QV4::ReturnedValue QQuickJSContext2DPrototype::method_getLineDash(const QV4::Fun
     \endcode
     \endtable
 
-    \sa setLineDash
+    \sa getLineDash(), lineDashOffset
   */
 QV4::ReturnedValue QQuickJSContext2DPrototype::method_setLineDash(const QV4::FunctionObject *b, const QV4::Value *thisObject, const QV4::Value *argv, int argc)
 {
@@ -2083,8 +2083,10 @@ QV4::ReturnedValue QQuickJSContext2DPrototype::method_setLineDash(const QV4::Fun
     \qmlproperty real QtQuick::Context2D::lineDashOffset
     \since QtQuick 2.11
 
-     Holds the current line dash offset
-     The default line dash ofset value is 0
+     Holds the current line dash offset.
+     The default line dash offset value is \c 0.
+
+     \sa getLineDash(), setLineDash()
  */
 QV4::ReturnedValue QQuickJSContext2D::method_get_lineDashOffset(const QV4::FunctionObject *b, const QV4::Value *thisObject, const QV4::Value *, int)
 {
diff --git a/src/quick/items/qquickaccessibleattached.cpp b/src/quick/items/qquickaccessibleattached.cpp
index 0168c3160c..c150e4efa2 100644
--- a/src/quick/items/qquickaccessibleattached.cpp
+++ b/src/quick/items/qquickaccessibleattached.cpp
@@ -390,6 +390,49 @@ QQuickAccessibleAttached::~QQuickAccessibleAttached()
 {
 }
 
+void QQuickAccessibleAttached::setRole(QAccessible::Role role)
+{
+    if (role != m_role) {
+        m_role = role;
+        Q_EMIT roleChanged();
+        // There is no way to signify role changes at the moment.
+        // QAccessible::updateAccessibility(parent(), 0, QAccessible::);
+
+        switch (role) {
+        case QAccessible::CheckBox:
+        case QAccessible::RadioButton:
+            if (!m_stateExplicitlySet.focusable)
+                m_state.focusable = true;
+            if (!m_stateExplicitlySet.checkable)
+                m_state.checkable = true;
+            break;
+        case QAccessible::Button:
+        case QAccessible::MenuItem:
+        case QAccessible::PageTab:
+        case QAccessible::SpinBox:
+        case QAccessible::ComboBox:
+        case QAccessible::Terminal:
+        case QAccessible::ScrollBar:
+            if (!m_stateExplicitlySet.focusable)
+                m_state.focusable = true;
+            break;
+        case QAccessible::EditableText:
+            if (!m_stateExplicitlySet.editable)
+                m_state.editable = true;
+            if (!m_stateExplicitlySet.focusable)
+                m_state.focusable = true;
+            break;
+        case QAccessible::StaticText:
+            if (!m_stateExplicitlySet.readOnly) {
+                m_state.readOnly = true;
+            }
+            break;
+        default:
+            break;
+        }
+    }
+}
+
 QQuickAccessibleAttached *QQuickAccessibleAttached::qmlAttachedProperties(QObject *obj)
 {
     return new QQuickAccessibleAttached(obj);
diff --git a/src/quick/items/qquickaccessibleattached_p.h b/src/quick/items/qquickaccessibleattached_p.h
index 215a1e5db6..f4194ef13d 100644
--- a/src/quick/items/qquickaccessibleattached_p.h
+++ b/src/quick/items/qquickaccessibleattached_p.h
@@ -69,6 +69,7 @@ QT_BEGIN_NAMESPACE
     bool P() const { return m_state.P ; } \
     void set_ ## P(bool arg) \
     { \
+        m_stateExplicitlySet.P = true; \
         if (m_state.P == arg) \
             return; \
         m_state.P = arg; \
@@ -111,35 +112,7 @@ public:
     ~QQuickAccessibleAttached();
 
     QAccessible::Role role() const { return m_role; }
-    void setRole(QAccessible::Role role)
-    {
-        if (role != m_role) {
-            m_role = role;
-            Q_EMIT roleChanged();
-            // There is no way to signify role changes at the moment.
-            // QAccessible::updateAccessibility(parent(), 0, QAccessible::);
-
-            switch (role) {
-            case QAccessible::CheckBox:
-            case QAccessible::RadioButton:
-                m_state.focusable = true;
-                m_state.checkable = true;
-                break;
-            case QAccessible::Button:
-            case QAccessible::MenuItem:
-            case QAccessible::PageTab:
-            case QAccessible::EditableText:
-            case QAccessible::SpinBox:
-            case QAccessible::ComboBox:
-            case QAccessible::Terminal:
-            case QAccessible::ScrollBar:
-                m_state.focusable = true;
-                break;
-            default:
-                break;
-            }
-        }
-    }
+    void setRole(QAccessible::Role role);
     QString name() const {
         if (m_state.passwordEdit)
             return QString();
@@ -241,6 +214,7 @@ private:
 
     QAccessible::Role m_role;
     QAccessible::State m_state;
+    QAccessible::State m_stateExplicitlySet;
     QString m_name;
     QString m_description;
 
diff --git a/src/quick/items/qquickopenglshadereffect.cpp b/src/quick/items/qquickopenglshadereffect.cpp
index bc1f787b81..0cbabaa170 100644
--- a/src/quick/items/qquickopenglshadereffect.cpp
+++ b/src/quick/items/qquickopenglshadereffect.cpp
@@ -221,7 +221,7 @@ QQuickOpenGLShaderEffectCommon::~QQuickOpenGLShaderEffectCommon()
         clearSignalMappers(shaderType);
 }
 
-void QQuickOpenGLShaderEffectCommon::disconnectPropertySignals(QQuickItem *item, Key::ShaderType shaderType)
+void QQuickOpenGLShaderEffectCommon::disconnectPropertySignals(QObject *obj, Key::ShaderType shaderType)
 {
     for (int i = 0; i < uniformData[shaderType].size(); ++i) {
         if (signalMappers[shaderType].at(i) == 0)
@@ -229,12 +229,11 @@ void QQuickOpenGLShaderEffectCommon::disconnectPropertySignals(QQuickItem *item,
         const UniformData &d = uniformData[shaderType].at(i);
         auto mapper = signalMappers[shaderType].at(i);
         void *a = mapper;
-        QObjectPrivate::disconnect(item, mapper->signalIndex(), &a);
+        QObjectPrivate::disconnect(obj, mapper->signalIndex(), &a);
         if (d.specialType == UniformData::Sampler || d.specialType == UniformData::SamplerExternal) {
             QQuickItem *source = qobject_cast<QQuickItem *>(qvariant_cast<QObject *>(d.value));
             if (source) {
-                if (item->window())
-                    QQuickItemPrivate::get(source)->derefWindow();
+                QQuickItemPrivate::get(source)->derefWindow();
                 QObject::disconnect(source, SIGNAL(destroyed(QObject*)), host, SLOT(sourceDestroyed(QObject*)));
             }
         }
diff --git a/src/quick/items/qquickopenglshadereffect_p.h b/src/quick/items/qquickopenglshadereffect_p.h
index 0c2adadc62..3087c1eb0b 100644
--- a/src/quick/items/qquickopenglshadereffect_p.h
+++ b/src/quick/items/qquickopenglshadereffect_p.h
@@ -89,7 +89,7 @@ struct Q_QUICK_PRIVATE_EXPORT QQuickOpenGLShaderEffectCommon
 
     ~QQuickOpenGLShaderEffectCommon();
 
-    void disconnectPropertySignals(QQuickItem *item, Key::ShaderType shaderType);
+    void disconnectPropertySignals(QObject *item, Key::ShaderType shaderType);
     void connectPropertySignals(QQuickItem *item, const QMetaObject *itemMetaObject, Key::ShaderType shaderType);
     void updateParseLog(bool ignoreAttributes);
     void lookThroughShaderCode(QQuickItem *item, const QMetaObject *itemMetaObject, Key::ShaderType shaderType, const QByteArray &code);
diff --git a/src/quick/items/qquickopenglshadereffectnode.cpp b/src/quick/items/qquickopenglshadereffectnode.cpp
index f32b32491b..f96ebebcd6 100644
--- a/src/quick/items/qquickopenglshadereffectnode.cpp
+++ b/src/quick/items/qquickopenglshadereffectnode.cpp
@@ -477,11 +477,11 @@ void QQuickOpenGLShaderEffectMaterial::updateTextures() const
     }
 }
 
-void QQuickOpenGLShaderEffectMaterial::invalidateTextureProvider(QSGTextureProvider *provider)
+void QQuickOpenGLShaderEffectMaterial::invalidateTextureProvider(const QObject *provider)
 {
     for (int i = 0; i < textureProviders.size(); ++i) {
         if (provider == textureProviders.at(i))
-            textureProviders[i] = 0;
+            textureProviders[i] = nullptr;
     }
 }
 
@@ -505,10 +505,10 @@ void QQuickOpenGLShaderEffectNode::markDirtyTexture()
     Q_EMIT dirtyTexture();
 }
 
-void QQuickOpenGLShaderEffectNode::textureProviderDestroyed(QObject *object)
+void QQuickOpenGLShaderEffectNode::textureProviderDestroyed(const QObject *object)
 {
     Q_ASSERT(material());
-    static_cast<QQuickOpenGLShaderEffectMaterial *>(material())->invalidateTextureProvider(static_cast<QSGTextureProvider *>(object));
+    static_cast<QQuickOpenGLShaderEffectMaterial *>(material())->invalidateTextureProvider(object);
 }
 
 void QQuickOpenGLShaderEffectNode::preprocess()
diff --git a/src/quick/items/qquickopenglshadereffectnode_p.h b/src/quick/items/qquickopenglshadereffectnode_p.h
index 7c75bb3126..6d68ba87b9 100644
--- a/src/quick/items/qquickopenglshadereffectnode_p.h
+++ b/src/quick/items/qquickopenglshadereffectnode_p.h
@@ -122,7 +122,7 @@ public:
 
     void setProgramSource(const QQuickOpenGLShaderEffectMaterialKey &source);
     void updateTextures() const;
-    void invalidateTextureProvider(QSGTextureProvider *provider);
+    void invalidateTextureProvider(const QObject *provider);
 
     static void cleanupMaterialCache();
 
@@ -159,7 +159,7 @@ Q_SIGNALS:
 
 private Q_SLOTS:
     void markDirtyTexture();
-    void textureProviderDestroyed(QObject *object);
+    void textureProviderDestroyed(const QObject *object);
 };
 
 QT_END_NAMESPACE
diff --git a/src/quick/items/qquickshadereffect.cpp b/src/quick/items/qquickshadereffect.cpp
index ab79b69c8c..05d9e5e36d 100644
--- a/src/quick/items/qquickshadereffect.cpp
+++ b/src/quick/items/qquickshadereffect.cpp
@@ -795,7 +795,8 @@ bool QQuickShaderEffect::event(QEvent *e)
         return QQuickItem::event(e);
     }
 #endif
-    m_impl->handleEvent(e);
+    if (m_impl)
+        m_impl->handleEvent(e);
     return QQuickItem::event(e);
 }
 
diff --git a/src/quick/items/qquicktableview.cpp b/src/quick/items/qquicktableview.cpp
index 8f5130fc17..9583ef4231 100644
--- a/src/quick/items/qquicktableview.cpp
+++ b/src/quick/items/qquicktableview.cpp
@@ -305,9 +305,7 @@
     \l view, which means that the table's width could be larger or smaller than
     the viewport width. As a TableView cannot always know the exact width of
     the table without loading all columns in the model, the \c contentWidth is
-    usually an estimate based on the columns it has seen so far. This estimate
-    is recalculated whenever new columns are flicked into view, which means
-    that the content width can change dynamically.
+    usually an estimate based on the initially loaded table.
 
     If you know what the width of the table will be, assign a value to
     \c contentWidth, to avoid unnecessary calculations and updates to the
@@ -324,9 +322,7 @@
     \c view, which means that the table's height could be larger or smaller than the
     viewport height. As a TableView cannot always know the exact height of the
     table without loading all rows in the model, the \c contentHeight is
-    usually an estimate based on the rows it has seen so far. This estimate is
-    recalculated whenever new rows are flicked into view, which means that
-    the content height can change dynamically.
+    usually an estimate based on the initially loaded table.
 
     If you know what the height of the table will be, assign a
     value to \c contentHeight, to avoid unnecessary calculations and updates to
@@ -616,6 +612,7 @@ void QQuickTableViewPrivate::updateContentWidth()
     Q_Q(QQuickTableView);
 
     if (syncHorizontally) {
+        QBoolBlocker fixupGuard(inUpdateContentSize, true);
         q->QQuickFlickable::setContentWidth(syncView->contentWidth());
         return;
     }
@@ -632,6 +629,8 @@ void QQuickTableViewPrivate::updateContentWidth()
     const qreal remainingSpacing = columnsRemaining * cellSpacing.width();
     const qreal estimatedRemainingWidth = remainingColumnWidths + remainingSpacing;
     const qreal estimatedWidth = loadedTableOuterRect.right() + estimatedRemainingWidth;
+
+    QBoolBlocker fixupGuard(inUpdateContentSize, true);
     q->QQuickFlickable::setContentWidth(estimatedWidth);
 }
 
@@ -640,6 +639,7 @@ void QQuickTableViewPrivate::updateContentHeight()
     Q_Q(QQuickTableView);
 
     if (syncVertically) {
+        QBoolBlocker fixupGuard(inUpdateContentSize, true);
         q->QQuickFlickable::setContentHeight(syncView->contentHeight());
         return;
     }
@@ -656,64 +656,204 @@ void QQuickTableViewPrivate::updateContentHeight()
     const qreal remainingSpacing = rowsRemaining * cellSpacing.height();
     const qreal estimatedRemainingHeight = remainingRowHeights + remainingSpacing;
     const qreal estimatedHeight = loadedTableOuterRect.bottom() + estimatedRemainingHeight;
+
+    QBoolBlocker fixupGuard(inUpdateContentSize, true);
     q->QQuickFlickable::setContentHeight(estimatedHeight);
 }
 
-void QQuickTableViewPrivate::enforceTableAtOrigin()
+void QQuickTableViewPrivate::updateExtents()
 {
-    // Gaps before the first row/column can happen if rows/columns
-    // changes size while flicking e.g because of spacing changes or
-    // changes to a column maxWidth/row maxHeight. Check for this, and
-    // move the whole table rect accordingly.
-    bool layoutNeeded = false;
-    const qreal flickMargin = 50;
+    // When rows or columns outside the viewport are removed or added, or a rebuild
+    // forces us to guesstimate a new top-left, the edges of the table might end up
+    // out of sync with the edges of the content view. We detect this situation here, and
+    // move the origin to ensure that there will never be gaps at the end of the table.
+    // Normally we detect that the size of the whole table is not going to be equal to the
+    // size of the content view already when we load the last row/column, and especially
+    // before it's flicked completely inside the viewport. For those cases we simply adjust
+    // the origin/endExtent, to give a smooth flicking experience.
+    // But if flicking fast (e.g with a scrollbar), it can happen that the viewport ends up
+    // outside the end of the table in just one viewport update. To avoid a "blink" in the
+    // viewport when that happens, we "move" the loaded table into the viewport to cover it.
+    Q_Q(QQuickTableView);
 
-    const bool noMoreColumns = nextVisibleEdgeIndexAroundLoadedTable(Qt::LeftEdge) == kEdgeIndexAtEnd;
-    const bool noMoreRows = nextVisibleEdgeIndexAroundLoadedTable(Qt::TopEdge) == kEdgeIndexAtEnd;
+    bool tableMovedHorizontally = false;
+    bool tableMovedVertically = false;
 
-    if (noMoreColumns) {
-        if (!qFuzzyIsNull(loadedTableOuterRect.left())) {
-            // There are no more columns, but the table rect
-            // is not at origin. So we move it there.
-            loadedTableOuterRect.moveLeft(0);
-            layoutNeeded = true;
+    const int nextLeftColumn = nextVisibleEdgeIndexAroundLoadedTable(Qt::LeftEdge);
+    const int nextRightColumn = nextVisibleEdgeIndexAroundLoadedTable(Qt::RightEdge);
+    const int nextTopRow = nextVisibleEdgeIndexAroundLoadedTable(Qt::TopEdge);
+    const int nextBottomRow = nextVisibleEdgeIndexAroundLoadedTable(Qt::BottomEdge);
+
+    if (syncHorizontally) {
+        const auto syncView_d = syncView->d_func();
+        origin.rx() = syncView_d->origin.x();
+        endExtent.rwidth() = syncView_d->endExtent.width();
+        hData.markExtentsDirty();
+    } else if (nextLeftColumn == kEdgeIndexAtEnd) {
+        // There are no more columns to load on the left side of the table.
+        // In that case, we ensure that the origin match the beginning of the table.
+        if (loadedTableOuterRect.left() > viewportRect.left()) {
+            // We have a blank area at the left end of the viewport. In that case we don't have time to
+            // wait for the viewport to move (after changing origin), since that will take an extra
+            // update cycle, which will be visible as a blink. Instead, unless the blank spot is just
+            // us overshooting, we brute force the loaded table inside the already existing viewport.
+            if (loadedTableOuterRect.left() > origin.x()) {
+                const qreal diff = loadedTableOuterRect.left() - origin.x();
+                loadedTableOuterRect.moveLeft(loadedTableOuterRect.left() - diff);
+                loadedTableInnerRect.moveLeft(loadedTableInnerRect.left() - diff);
+                tableMovedHorizontally = true;
+            }
         }
-    } else {
-        if (loadedTableOuterRect.left() <= 0) {
-            // The table rect is at origin, or outside. But we still have
-            // more visible columns to the left. So we need to make some
-            // space so that they can be flicked in.
-            loadedTableOuterRect.moveLeft(flickMargin);
-            layoutNeeded = true;
+        origin.rx() = loadedTableOuterRect.left();
+        hData.markExtentsDirty();
+    } else if (loadedTableOuterRect.left() <= origin.x() + cellSpacing.width()) {
+        // The table rect is at the origin, or outside, but we still have more
+        // visible columns to the left. So we try to guesstimate how much space
+        // the rest of the columns will occupy, and move the origin accordingly.
+        const int columnsRemaining = nextLeftColumn + 1;
+        const qreal remainingColumnWidths = columnsRemaining * averageEdgeSize.width();
+        const qreal remainingSpacing = columnsRemaining * cellSpacing.width();
+        const qreal estimatedRemainingWidth = remainingColumnWidths + remainingSpacing;
+        origin.rx() = loadedTableOuterRect.left() - estimatedRemainingWidth;
+        hData.markExtentsDirty();
+    } else if (nextRightColumn == kEdgeIndexAtEnd) {
+        // There are no more columns to load on the right side of the table.
+        // In that case, we ensure that the end of the content view match the end of the table.
+        if (loadedTableOuterRect.right() < viewportRect.right()) {
+            // We have a blank area at the right end of the viewport. In that case we don't have time to
+            // wait for the viewport to move (after changing endExtent), since that will take an extra
+            // update cycle, which will be visible as a blink. Instead, unless the blank spot is just
+            // us overshooting, we brute force the loaded table inside the already existing viewport.
+            const qreal w = qMin(viewportRect.right(), q->contentWidth() + endExtent.width());
+            if (loadedTableOuterRect.right() < w) {
+                const qreal diff = loadedTableOuterRect.right() - w;
+                loadedTableOuterRect.moveRight(loadedTableOuterRect.right() - diff);
+                loadedTableInnerRect.moveRight(loadedTableInnerRect.right() - diff);
+                tableMovedHorizontally = true;
+            }
         }
+        endExtent.rwidth() = loadedTableOuterRect.right() - q->contentWidth();
+        hData.markExtentsDirty();
+    } else if (loadedTableOuterRect.right() >= q->contentWidth() + endExtent.width() - cellSpacing.width()) {
+        // The right-most column is outside the end of the content view, and we
+        // still have more visible columns in the model. This can happen if the application
+        // has set a fixed content width.
+        const int columnsRemaining = tableSize.width() - nextRightColumn;
+        const qreal remainingColumnWidths = columnsRemaining * averageEdgeSize.width();
+        const qreal remainingSpacing = columnsRemaining * cellSpacing.width();
+        const qreal estimatedRemainingWidth = remainingColumnWidths + remainingSpacing;
+        const qreal pixelsOutsideContentWidth = loadedTableOuterRect.right() - q->contentWidth();
+        endExtent.rwidth() = pixelsOutsideContentWidth + estimatedRemainingWidth;
+        hData.markExtentsDirty();
     }
 
-    if (noMoreRows) {
-        if (!qFuzzyIsNull(loadedTableOuterRect.top())) {
-            loadedTableOuterRect.moveTop(0);
-            layoutNeeded = true;
+    if (syncVertically) {
+        const auto syncView_d = syncView->d_func();
+        origin.ry() = syncView_d->origin.y();
+        endExtent.rheight() = syncView_d->endExtent.height();
+        vData.markExtentsDirty();
+    } else if (nextTopRow == kEdgeIndexAtEnd) {
+        // There are no more rows to load on the top side of the table.
+        // In that case, we ensure that the origin match the beginning of the table.
+        if (loadedTableOuterRect.top() > viewportRect.top()) {
+            // We have a blank area at the top of the viewport. In that case we don't have time to
+            // wait for the viewport to move (after changing origin), since that will take an extra
+            // update cycle, which will be visible as a blink. Instead, unless the blank spot is just
+            // us overshooting, we brute force the loaded table inside the already existing viewport.
+            if (loadedTableOuterRect.top() > origin.y()) {
+                const qreal diff = loadedTableOuterRect.top() - origin.y();
+                loadedTableOuterRect.moveTop(loadedTableOuterRect.top() - diff);
+                loadedTableInnerRect.moveTop(loadedTableInnerRect.top() - diff);
+                tableMovedVertically = true;
+            }
         }
-    } else {
-        if (loadedTableOuterRect.top() <= 0) {
-            loadedTableOuterRect.moveTop(flickMargin);
-            layoutNeeded = true;
+        origin.ry() = loadedTableOuterRect.top();
+        vData.markExtentsDirty();
+    } else if (loadedTableOuterRect.top() <= origin.y() + cellSpacing.height()) {
+        // The table rect is at the origin, or outside, but we still have more
+        // visible rows at the top. So we try to guesstimate how much space
+        // the rest of the rows will occupy, and move the origin accordingly.
+        const int rowsRemaining = nextTopRow + 1;
+        const qreal remainingRowHeights = rowsRemaining * averageEdgeSize.height();
+        const qreal remainingSpacing = rowsRemaining * cellSpacing.height();
+        const qreal estimatedRemainingHeight = remainingRowHeights + remainingSpacing;
+        origin.ry() = loadedTableOuterRect.top() - estimatedRemainingHeight;
+        vData.markExtentsDirty();
+    } else if (nextBottomRow == kEdgeIndexAtEnd) {
+        // There are no more rows to load on the bottom side of the table.
+        // In that case, we ensure that the end of the content view match the end of the table.
+        if (loadedTableOuterRect.bottom() < viewportRect.bottom()) {
+            // We have a blank area at the bottom of the viewport. In that case we don't have time to
+            // wait for the viewport to move (after changing endExtent), since that will take an extra
+            // update cycle, which will be visible as a blink. Instead, unless the blank spot is just
+            // us overshooting, we brute force the loaded table inside the already existing viewport.
+            const qreal h = qMin(viewportRect.bottom(), q->contentHeight() + endExtent.height());
+            if (loadedTableOuterRect.bottom() < h) {
+                const qreal diff = loadedTableOuterRect.bottom() - h;
+                loadedTableOuterRect.moveBottom(loadedTableOuterRect.bottom() - diff);
+                loadedTableInnerRect.moveBottom(loadedTableInnerRect.bottom() - diff);
+                tableMovedVertically = true;
+            }
+        }
+        endExtent.rheight() = loadedTableOuterRect.bottom() - q->contentHeight();
+        vData.markExtentsDirty();
+    } else if (loadedTableOuterRect.bottom() >= q->contentHeight() + endExtent.height() - cellSpacing.height()) {
+        // The bottom-most row is outside the end of the content view, and we
+        // still have more visible rows in the model. This can happen if the application
+        // has set a fixed content height.
+        const int rowsRemaining = tableSize.height() - nextBottomRow;
+        const qreal remainingRowHeigts = rowsRemaining * averageEdgeSize.height();
+        const qreal remainingSpacing = rowsRemaining * cellSpacing.height();
+        const qreal estimatedRemainingHeight = remainingRowHeigts + remainingSpacing;
+        const qreal pixelsOutsideContentHeight = loadedTableOuterRect.bottom() - q->contentHeight();
+        endExtent.rheight() = pixelsOutsideContentHeight + estimatedRemainingHeight;
+        vData.markExtentsDirty();
+    }
+
+    if (tableMovedHorizontally || tableMovedVertically) {
+        qCDebug(lcTableViewDelegateLifecycle) << "move table to" << loadedTableOuterRect;
+
+        // relayoutTableItems() will take care of moving the existing
+        // delegate items into the new loadedTableOuterRect.
+        relayoutTableItems();
+
+        // Inform the sync children that they need to rebuild to stay in sync
+        for (auto syncChild : qAsConst(syncChildren)) {
+            auto syncChild_d = syncChild->d_func();
+            syncChild_d->scheduledRebuildOptions |= RebuildOption::ViewportOnly;
+            if (tableMovedHorizontally)
+                syncChild_d->scheduledRebuildOptions |= RebuildOption::CalculateNewTopLeftColumn;
+            if (tableMovedVertically)
+                syncChild_d->scheduledRebuildOptions |= RebuildOption::CalculateNewTopLeftRow;
         }
     }
 
-    if (layoutNeeded) {
-        qCDebug(lcTableViewDelegateLifecycle);
-        relayoutTableItems();
+    if (hData.minExtentDirty || vData.minExtentDirty) {
+        qCDebug(lcTableViewDelegateLifecycle) << "move origin and endExtent to:" << origin << endExtent;
+        // updateBeginningEnd() will let the new extents take effect. This will also change the
+        // visualArea of the flickable, which again will cause any attached scrollbars to adjust
+        // the position of the handle. Note the latter will cause the viewport to move once more.
+        updateBeginningEnd();
     }
 }
 
 void QQuickTableViewPrivate::updateAverageEdgeSize()
 {
-    const int loadedRowCount = loadedRows.count();
-    const int loadedColumnCount = loadedColumns.count();
-    const qreal accRowSpacing = (loadedRowCount - 1) * cellSpacing.height();
-    const qreal accColumnSpacing = (loadedColumnCount - 1) * cellSpacing.width();
-    averageEdgeSize.setHeight((loadedTableOuterRect.height() - accRowSpacing) / loadedRowCount);
-    averageEdgeSize.setWidth((loadedTableOuterRect.width() - accColumnSpacing) / loadedColumnCount);
+    if (explicitContentWidth.isValid()) {
+        const qreal accColumnSpacing = (tableSize.width() - 1) * cellSpacing.width();
+        averageEdgeSize.setWidth((explicitContentWidth - accColumnSpacing) / tableSize.width());
+    } else {
+        const qreal accColumnSpacing = (loadedColumns.count() - 1) * cellSpacing.width();
+        averageEdgeSize.setWidth((loadedTableOuterRect.width() - accColumnSpacing) / loadedColumns.count());
+    }
+
+    if (explicitContentHeight.isValid()) {
+        const qreal accRowSpacing = (tableSize.height() - 1) * cellSpacing.height();
+        averageEdgeSize.setHeight((explicitContentHeight - accRowSpacing) / tableSize.height());
+    } else {
+        const qreal accRowSpacing = (loadedRows.count() - 1) * cellSpacing.height();
+        averageEdgeSize.setHeight((loadedTableOuterRect.height() - accRowSpacing) / loadedRows.count());
+    }
 }
 
 void QQuickTableViewPrivate::syncLoadedTableRectFromLoadedTable()
@@ -770,13 +910,12 @@ void QQuickTableViewPrivate::forceLayout()
 
     scheduleRebuildTable(rebuildOptions);
 
-    if (polishing) {
+    auto rootView = rootSyncView();
+    const bool updated = rootView->d_func()->updateTableRecursive();
+    if (!updated) {
         qWarning() << "TableView::forceLayout(): Cannot do an immediate re-layout during an ongoing layout!";
-        q_func()->polish();
-        return;
+        rootView->polish();
     }
-
-    updatePolish();
 }
 
 void QQuickTableViewPrivate::syncLoadedTableFromLoadRequest()
@@ -1212,19 +1351,6 @@ bool QQuickTableViewPrivate::isRowHidden(int row)
     return qFuzzyIsNull(getRowHeight(row));
 }
 
-void QQuickTableViewPrivate::relayoutTable()
-{
-    clearEdgeSizeCache();
-    relayoutTableItems();
-    syncLoadedTableRectFromLoadedTable();
-    enforceTableAtOrigin();
-    updateContentWidth();
-    updateContentHeight();
-    // Return back to updatePolish to loadAndUnloadVisibleEdges()
-    // since the re-layout might have caused some edges to be pushed
-    // out, while others might have been pushed in.
-}
-
 void QQuickTableViewPrivate::relayoutTableItems()
 {
     qCDebug(lcTableViewDelegateLifecycle);
@@ -1409,20 +1535,7 @@ void QQuickTableViewPrivate::processLoadRequest()
     if (rebuildState == RebuildState::Done) {
         // Loading of this edge was not done as a part of a rebuild, but
         // instead as an incremental build after e.g a flick.
-        switch (loadRequest.edge()) {
-        case Qt::LeftEdge:
-        case Qt::TopEdge:
-            enforceTableAtOrigin();
-            break;
-        case Qt::RightEdge:
-            updateAverageEdgeSize();
-            updateContentWidth();
-            break;
-        case Qt::BottomEdge:
-            updateAverageEdgeSize();
-            updateContentHeight();
-            break;
-        }
+        updateExtents();
         drainReusePoolAfterLoadRequest();
     }
 
@@ -1637,16 +1750,29 @@ void QQuickTableViewPrivate::beginRebuildTable()
     else if (rebuildOptions & RebuildOption::ViewportOnly)
         releaseLoadedItems(reusableFlag);
 
+    if (rebuildOptions & RebuildOption::All) {
+        origin = QPointF(0, 0);
+        endExtent = QSizeF(0, 0);
+        hData.markExtentsDirty();
+        vData.markExtentsDirty();
+        updateBeginningEnd();
+    }
+
     loadedColumns.clear();
     loadedRows.clear();
     loadedTableOuterRect = QRect();
     loadedTableInnerRect = QRect();
     clearEdgeSizeCache();
 
-    if (syncHorizontally)
+    if (syncHorizontally) {
         setLocalViewportX(syncView->contentX());
-    if (syncVertically)
+        viewportRect.moveLeft(syncView->d_func()->viewportRect.left());
+    }
+
+    if (syncVertically) {
         setLocalViewportY(syncView->contentY());
+        viewportRect.moveTop(syncView->d_func()->viewportRect.top());
+    }
 
     if (!model) {
         qCDebug(lcTableViewDelegateLifecycle()) << "no model found, leaving table empty";
@@ -1690,12 +1816,29 @@ void QQuickTableViewPrivate::layoutAfterLoadingInitialTable()
         // columns, since during the process, we didn't have all the items
         // available yet for the calculation. So we do it now. The exception
         // is if we specifically only requested a relayout.
-        relayoutTable();
+        clearEdgeSizeCache();
+        relayoutTableItems();
+        syncLoadedTableRectFromLoadedTable();
+    }
+
+    if (syncView || rebuildOptions.testFlag(RebuildOption::All)) {
+        // We try to limit how often we update the content size. The main reason is that is has a
+        // tendency to cause flicker in the viewport if it happens while flicking. But another just
+        // as valid reason is that we actually never really know what the size of the full table will
+        // ever be. Even if e.g spacing changes, and we normally would assume that the size of the table
+        // would increase accordingly, the model might also at some point have removed/hidden/resized
+        // rows/columns outside the viewport. This would also affect the size, but since we don't load
+        // rows or columns outside the viewport, this information is ignored. And even if we did, we
+        // might also have been fast-flicked to a new location at some point, and started a new rebuild
+        // there based on a new guesstimated top-left cell. Either way, changing the content size
+        // based on the currently visible row/columns/spacing can be really off. So instead of pretending
+        // that we know what the actual size of the table is, we just keep the first guesstimate.
+        updateAverageEdgeSize();
+        updateContentWidth();
+        updateContentHeight();
     }
 
-    updateAverageEdgeSize();
-    updateContentWidth();
-    updateContentHeight();
+    updateExtents();
 }
 
 void QQuickTableViewPrivate::unloadEdge(Qt::Edge edge)
@@ -1710,8 +1853,6 @@ void QQuickTableViewPrivate::unloadEdge(Qt::Edge edge)
             unloadItem(QPoint(column, r.key()));
         loadedColumns.remove(column);
         syncLoadedTableRectFromLoadedTable();
-        updateAverageEdgeSize();
-        updateContentWidth();
         break; }
     case Qt::TopEdge:
     case Qt::BottomEdge: {
@@ -1720,8 +1861,6 @@ void QQuickTableViewPrivate::unloadEdge(Qt::Edge edge)
             unloadItem(QPoint(c.key(), row));
         loadedRows.remove(row);
         syncLoadedTableRectFromLoadedTable();
-        updateAverageEdgeSize();
-        updateContentHeight();
         break; }
     }
 
@@ -1925,8 +2064,17 @@ bool QQuickTableViewPrivate::updateTable()
 
 void QQuickTableViewPrivate::fixup(QQuickFlickablePrivate::AxisData &data, qreal minExtent, qreal maxExtent)
 {
-    if (scheduledRebuildOptions || rebuildState != RebuildState::Done)
+    if (inUpdateContentSize) {
+        // We update the content size dynamically as we load and unload edges.
+        // Unfortunately, this also triggers a call to this function. The base
+        // implementation will do things like start a momentum animation or move
+        // the content view somewhere else, which causes glitches. This can
+        // especially happen if flicking on one of the syncView children, which triggers
+        // an update to our content size. In that case, the base implementation don't know
+        // that the view is being indirectly dragged, and will therefore do strange things as
+        // it tries to 'fixup' the geometry. So we use a guard to prevent this from happening.
         return;
+    }
 
     QQuickFlickablePrivate::fixup(data, minExtent, maxExtent);
 }
@@ -2011,13 +2159,11 @@ void QQuickTableViewPrivate::syncWithPendingChanges()
     Q_Q(QQuickTableView);
     viewportRect = QRectF(q->contentX(), q->contentY(), q->width(), q->height());
 
-    // Sync rebuild options first, in case we schedule a rebuild from one of the
-    // other sync calls above. If so, we need to start a new rebuild from the top.
-    syncRebuildOptions();
-
     syncModel();
     syncDelegate();
     syncSyncView();
+
+    syncRebuildOptions();
 }
 
 void QQuickTableViewPrivate::syncRebuildOptions()
@@ -2107,7 +2253,6 @@ void QQuickTableViewPrivate::syncSyncView()
 
             assignedSyncView->d_func()->syncChildren.append(q);
             scheduledRebuildOptions |= RebuildOption::ViewportOnly;
-            q->polish();
         }
 
         syncView = assignedSyncView;
@@ -2120,6 +2265,21 @@ void QQuickTableViewPrivate::syncSyncView()
         q->setColumnSpacing(syncView->columnSpacing());
     if (syncVertically)
         q->setRowSpacing(syncView->rowSpacing());
+
+    if (syncView && loadedItems.isEmpty() && !tableSize.isEmpty()) {
+        // When we have a syncView, we can sometimes temporarily end up with no loaded items.
+        // This can happen if the syncView has a model with more rows or columns than us, in
+        // which case the viewport can end up in a place where we have no rows or columns to
+        // show. In that case, check now if the viewport has been flicked back again, and
+        // that we can rebuild the table with a visible top-left cell.
+        const auto syncView_d = syncView->d_func();
+        if (!syncView_d->loadedItems.isEmpty()) {
+            if (syncHorizontally && syncView_d->leftColumn() <= tableSize.width() - 1)
+                scheduledRebuildOptions |= QQuickTableViewPrivate::RebuildOption::ViewportOnly;
+            else if (syncVertically && syncView_d->topRow() <= tableSize.height() - 1)
+                scheduledRebuildOptions |= QQuickTableViewPrivate::RebuildOption::ViewportOnly;
+        }
+    }
 }
 
 void QQuickTableViewPrivate::connectToModel()
@@ -2254,7 +2414,6 @@ void QQuickTableViewPrivate::modelResetCallback()
 void QQuickTableViewPrivate::scheduleRebuildIfFastFlick()
 {
     Q_Q(QQuickTableView);
-
     // If the viewport has moved more than one page vertically or horizontally, we switch
     // strategy from refilling edges around the current table to instead rebuild the table
     // from scratch inside the new viewport. This will greatly improve performance when flicking
@@ -2345,6 +2504,26 @@ QQuickTableView::QQuickTableView(QQuickTableViewPrivate &dd, QQuickItem *parent)
     setFlag(QQuickItem::ItemIsFocusScope);
 }
 
+qreal QQuickTableView::minXExtent() const
+{
+    return QQuickFlickable::minXExtent() - d_func()->origin.x();
+}
+
+qreal QQuickTableView::maxXExtent() const
+{
+    return QQuickFlickable::maxXExtent() - d_func()->endExtent.width();
+}
+
+qreal QQuickTableView::minYExtent() const
+{
+    return QQuickFlickable::minYExtent() - d_func()->origin.y();
+}
+
+qreal QQuickTableView::maxYExtent() const
+{
+    return QQuickFlickable::maxYExtent() - d_func()->endExtent.height();
+}
+
 int QQuickTableView::rows() const
 {
     return d_func()->tableSize.height();
diff --git a/src/quick/items/qquicktableview_p.h b/src/quick/items/qquicktableview_p.h
index 3d46221574..3b113efa4f 100644
--- a/src/quick/items/qquicktableview_p.h
+++ b/src/quick/items/qquicktableview_p.h
@@ -147,6 +147,11 @@ private:
     Q_DISABLE_COPY(QQuickTableView)
     Q_DECLARE_PRIVATE(QQuickTableView)
 
+    qreal minXExtent() const override;
+    qreal maxXExtent() const override;
+    qreal minYExtent() const override;
+    qreal maxYExtent() const override;
+
     Q_PRIVATE_SLOT(d_func(), void _q_componentFinalized())
 };
 
diff --git a/src/quick/items/qquicktableview_p_p.h b/src/quick/items/qquicktableview_p_p.h
index 7f2aee9105..b66ac66dec 100644
--- a/src/quick/items/qquicktableview_p_p.h
+++ b/src/quick/items/qquicktableview_p_p.h
@@ -251,6 +251,9 @@ public:
     QRectF loadedTableOuterRect;
     QRectF loadedTableInnerRect;
 
+    QPointF origin = QPointF(0, 0);
+    QSizeF endExtent = QSizeF(0, 0);
+
     QRectF viewportRect = QRectF(0, 0, -1, -1);
 
     QSize tableSize;
@@ -272,6 +275,7 @@ public:
     bool syncHorizontally = false;
     bool inSetLocalViewportPos = false;
     bool inSyncViewportPosRecursive = false;
+    bool inUpdateContentSize = false;
 
     QJSValue rowHeightProvider;
     QJSValue columnWidthProvider;
@@ -337,7 +341,6 @@ public:
 
     bool updateTableRecursive();
     bool updateTable();
-    void relayoutTable();
     void relayoutTableItems();
 
     void layoutVerticalEdge(Qt::Edge tableEdge);
@@ -350,7 +353,7 @@ public:
     void updateAverageEdgeSize();
     void forceLayout();
 
-    void enforceTableAtOrigin();
+    void updateExtents();
     void syncLoadedTableRectFromLoadedTable();
     void syncLoadedTableFromLoadRequest();
 
diff --git a/src/quick/items/qquicktext.cpp b/src/quick/items/qquicktext.cpp
index 6d343a91ce..ae849aeb4b 100644
--- a/src/quick/items/qquicktext.cpp
+++ b/src/quick/items/qquicktext.cpp
@@ -1653,13 +1653,17 @@ void QQuickText::setText(const QString &n)
     if (d->text == n)
         return;
 
-    d->richText = d->format == RichText;
+    d->markdownText = d->format == MarkdownText;
+    d->richText = d->format == RichText || d->markdownText;
     d->styledText = d->format == StyledText || (d->format == AutoText && Qt::mightBeRichText(n));
     d->text = n;
     if (isComponentComplete()) {
         if (d->richText) {
             d->ensureDoc();
-            d->extra->doc->setText(n);
+            if (d->markdownText)
+                d->extra->doc->setMarkdownText(n);
+            else
+                d->extra->doc->setText(n);
             d->rightToLeftText = d->extra->doc->toPlainText().isRightToLeft();
         } else {
             d->clearFormats();
@@ -2146,7 +2150,8 @@ void QQuickText::setTextFormat(TextFormat format)
         return;
     d->format = format;
     bool wasRich = d->richText;
-    d->richText = format == RichText;
+    d->markdownText = format == MarkdownText;
+    d->richText = format == RichText || d->markdownText;
     d->styledText = format == StyledText || (format == AutoText && Qt::mightBeRichText(d->text));
 
     if (isComponentComplete()) {
@@ -2687,7 +2692,10 @@ void QQuickText::componentComplete()
     if (d->updateOnComponentComplete) {
         if (d->richText) {
             d->ensureDoc();
-            d->extra->doc->setText(d->text);
+            if (d->markdownText)
+                d->extra->doc->setMarkdownText(d->text);
+            else
+                d->extra->doc->setText(d->text);
             d->rightToLeftText = d->extra->doc->toPlainText().isRightToLeft();
         } else {
             d->rightToLeftText = d->text.isRightToLeft();
diff --git a/src/quick/items/qquicktext_p.h b/src/quick/items/qquicktext_p.h
index 1af60051fb..45f387cb12 100644
--- a/src/quick/items/qquicktext_p.h
+++ b/src/quick/items/qquicktext_p.h
@@ -121,6 +121,7 @@ public:
     Q_ENUM(TextStyle)
     enum TextFormat { PlainText = Qt::PlainText,
                        RichText = Qt::RichText,
+                       MarkdownText = Qt::MarkdownText,
                        AutoText = Qt::AutoText,
                        StyledText = 4 };
     Q_ENUM(TextFormat)
diff --git a/src/quick/items/qquicktext_p_p.h b/src/quick/items/qquicktext_p_p.h
index efa45e0958..c01998b100 100644
--- a/src/quick/items/qquicktext_p_p.h
+++ b/src/quick/items/qquicktext_p_p.h
@@ -161,6 +161,7 @@ public:
     bool updateOnComponentComplete:1;
     bool richText:1;
     bool styledText:1;
+    bool markdownText:1;
     bool widthExceeded:1;
     bool heightExceeded:1;
     bool internalWidthUpdate:1;
diff --git a/src/quick/items/qquicktextcontrol.cpp b/src/quick/items/qquicktextcontrol.cpp
index a7a90c9134..caef24293a 100644
--- a/src/quick/items/qquicktextcontrol.cpp
+++ b/src/quick/items/qquicktextcontrol.cpp
@@ -1297,6 +1297,7 @@ void QQuickTextControlPrivate::inputMethodEvent(QInputMethodEvent *e)
             || e->preeditString() != cursor.block().layout()->preeditAreaText()
             || e->replacementLength() > 0;
     bool forceSelectionChanged = false;
+    int oldCursorPos = cursor.position();
 
     cursor.beginEditBlock();
     if (isGettingInput) {
@@ -1365,6 +1366,8 @@ void QQuickTextControlPrivate::inputMethodEvent(QInputMethodEvent *e)
     QTextCursorPrivate *cursor_d = QTextCursorPrivate::getPrivate(&cursor);
     if (cursor_d)
         cursor_d->setX();
+    if (cursor.position() != oldCursorPos)
+        emit q->cursorPositionChanged();
     q->updateCursorRectangle(oldPreeditCursor != preeditCursor || forceSelectionChanged || isGettingInput);
     selectionChanged(forceSelectionChanged);
 }
diff --git a/src/quick/items/qquicktextdocument.cpp b/src/quick/items/qquicktextdocument.cpp
index 06ac5804c4..021bbca0f6 100644
--- a/src/quick/items/qquicktextdocument.cpp
+++ b/src/quick/items/qquicktextdocument.cpp
@@ -237,6 +237,14 @@ void QQuickTextDocumentWithImageResources::setText(const QString &text)
 #endif
 }
 
+#if QT_CONFIG(textmarkdownreader)
+void QQuickTextDocumentWithImageResources::setMarkdownText(const QString &text)
+{
+    clearResources();
+    QTextDocument::setMarkdown(text);
+}
+#endif
+
 QSet<QUrl> QQuickTextDocumentWithImageResources::errors;
 
 QT_END_NAMESPACE
diff --git a/src/quick/items/qquicktextdocument_p.h b/src/quick/items/qquicktextdocument_p.h
index 1218b12b89..9c5152d442 100644
--- a/src/quick/items/qquicktextdocument_p.h
+++ b/src/quick/items/qquicktextdocument_p.h
@@ -73,6 +73,9 @@ public:
     virtual ~QQuickTextDocumentWithImageResources();
 
     void setText(const QString &);
+#if QT_CONFIG(textmarkdownreader)
+    void setMarkdownText(const QString &);
+#endif
     int resourcesLoading() const { return outstanding; }
 
     QSizeF intrinsicSize(QTextDocument *doc, int posInDocument, const QTextFormat &format) override;
diff --git a/src/quick/items/qquicktextedit.cpp b/src/quick/items/qquicktextedit.cpp
index 6b4b118eb7..b299e7c92f 100644
--- a/src/quick/items/qquicktextedit.cpp
+++ b/src/quick/items/qquicktextedit.cpp
@@ -2298,7 +2298,6 @@ void QQuickTextEditPrivate::init()
     qmlobject_connect(control, QQuickTextControl, SIGNAL(cursorPositionChanged()), q, QQuickTextEdit, SIGNAL(cursorPositionChanged()));
     qmlobject_connect(control, QQuickTextControl, SIGNAL(cursorRectangleChanged()), q, QQuickTextEdit, SLOT(moveCursorDelegate()));
     qmlobject_connect(control, QQuickTextControl, SIGNAL(linkActivated(QString)), q, QQuickTextEdit, SIGNAL(linkActivated(QString)));
-    qmlobject_connect(control, QQuickTextControl, SIGNAL(linkHovered(QString)), q, QQuickTextEdit, SIGNAL(linkHovered(QString)));
     qmlobject_connect(control, QQuickTextControl, SIGNAL(overwriteModeChanged(bool)), q, QQuickTextEdit, SIGNAL(overwriteModeChanged(bool)));
     qmlobject_connect(control, QQuickTextControl, SIGNAL(textChanged()), q, QQuickTextEdit, SLOT(q_textChanged()));
     qmlobject_connect(control, QQuickTextControl, SIGNAL(preeditTextChanged()), q, QQuickTextEdit, SIGNAL(preeditTextChanged()));
@@ -2310,6 +2309,7 @@ void QQuickTextEditPrivate::init()
     qmlobject_connect(document, QQuickTextDocumentWithImageResources, SIGNAL(imagesLoaded()), q, QQuickTextEdit, SLOT(updateSize()));
     QObject::connect(document, &QQuickTextDocumentWithImageResources::contentsChange, q, &QQuickTextEdit::q_contentsChange);
     QObject::connect(document->documentLayout(), &QAbstractTextDocumentLayout::updateBlock, q, &QQuickTextEdit::invalidateBlock);
+    QObject::connect(control, &QQuickTextControl::linkHovered, q, &QQuickTextEdit::q_linkHovered);
 
     document->setDefaultFont(font);
     document->setDocumentMargin(textMargin);
@@ -2317,6 +2317,9 @@ void QQuickTextEditPrivate::init()
     document->setUndoRedoEnabled(true);
     updateDefaultTextOption();
     q->updateSize();
+#if QT_CONFIG(cursor)
+    q->setCursor(Qt::IBeamCursor);
+#endif
 }
 
 void QQuickTextEditPrivate::resetInputMethod()
@@ -2584,6 +2587,20 @@ void QQuickTextEdit::updateCursor()
     }
 }
 
+void QQuickTextEdit::q_linkHovered(const QString &link)
+{
+    Q_D(QQuickTextEdit);
+    emit linkHovered(link);
+#if QT_CONFIG(cursor)
+    if (link.isEmpty()) {
+        setCursor(d->cursorToRestoreAfterHover);
+    } else if (cursor().shape() != Qt::PointingHandCursor) {
+        d->cursorToRestoreAfterHover = cursor().shape();
+        setCursor(Qt::PointingHandCursor);
+    }
+#endif
+}
+
 void QQuickTextEdit::q_updateAlignment()
 {
     Q_D(QQuickTextEdit);
diff --git a/src/quick/items/qquicktextedit_p.h b/src/quick/items/qquicktextedit_p.h
index 7a847ffeae..259a614d6b 100644
--- a/src/quick/items/qquicktextedit_p.h
+++ b/src/quick/items/qquicktextedit_p.h
@@ -374,6 +374,7 @@ private Q_SLOTS:
     void updateWholeDocument();
     void invalidateBlock(const QTextBlock &block);
     void updateCursor();
+    void q_linkHovered(const QString &link);
     void q_updateAlignment();
     void updateSize();
     void triggerPreprocess();
diff --git a/src/quick/items/qquicktextedit_p_p.h b/src/quick/items/qquicktextedit_p_p.h
index 46d3d5ff6b..389ce3175c 100644
--- a/src/quick/items/qquicktextedit_p_p.h
+++ b/src/quick/items/qquicktextedit_p_p.h
@@ -207,6 +207,7 @@ public:
     Qt::InputMethodHints inputMethodHints;
 #endif
     UpdateType updateType;
+    Qt::CursorShape cursorToRestoreAfterHover = Qt::IBeamCursor;
 
     bool dirty : 1;
     bool richText : 1;
diff --git a/src/quick/items/qquicktextnodeengine.cpp b/src/quick/items/qquicktextnodeengine.cpp
index a1b5eb1faf..32478ba375 100644
--- a/src/quick/items/qquicktextnodeengine.cpp
+++ b/src/quick/items/qquicktextnodeengine.cpp
@@ -1011,6 +1011,17 @@ void QQuickTextNodeEngine::addTextBlock(QTextDocument *textDocument, const QText
                 break;
             };
 
+            switch (block.blockFormat().marker()) {
+            case QTextBlockFormat::Checked:
+                listItemBullet = QChar(0x2612); // Checked checkbox
+                break;
+            case QTextBlockFormat::Unchecked:
+                listItemBullet = QChar(0x2610); // Unchecked checkbox
+                break;
+            case QTextBlockFormat::NoMarker:
+                break;
+            }
+
             QSizeF size(fontMetrics.horizontalAdvance(listItemBullet), fontMetrics.height());
             qreal xoff = fontMetrics.horizontalAdvance(QLatin1Char(' '));
             if (block.textDirection() == Qt::LeftToRight)
diff --git a/src/quick/items/qquickwindow.cpp b/src/quick/items/qquickwindow.cpp
index f3a2b07620..5dcd101462 100644
--- a/src/quick/items/qquickwindow.cpp
+++ b/src/quick/items/qquickwindow.cpp
@@ -64,6 +64,7 @@
 #include <QtGui/qpainter.h>
 #include <QtGui/qevent.h>
 #include <QtGui/qmatrix4x4.h>
+#include <QtGui/qpa/qplatformtheme.h>
 #include <QtCore/qvarlengtharray.h>
 #include <QtCore/qabstractanimation.h>
 #include <QtCore/QLibraryInfo>
@@ -632,25 +633,28 @@ static QMouseEvent *touchToMouseEvent(QEvent::Type type, const QTouchEvent::Touc
     return me;
 }
 
-bool QQuickWindowPrivate::checkIfDoubleClicked(ulong newPressEventTimestamp)
+bool QQuickWindowPrivate::checkIfDoubleTapped(ulong newPressEventTimestamp, QPoint newPressPos)
 {
-    bool doubleClicked;
+    bool doubleClicked = false;
+
+    if (touchMousePressTimestamp > 0) {
+        QPoint distanceBetweenPresses = newPressPos - touchMousePressPos;
+        const int doubleTapDistance = QGuiApplicationPrivate::platformTheme()->themeHint(QPlatformTheme::TouchDoubleTapDistance).toInt();
+        doubleClicked = (qAbs(distanceBetweenPresses.x()) <= doubleTapDistance) && (qAbs(distanceBetweenPresses.y()) <= doubleTapDistance);
 
-    if (touchMousePressTimestamp == 0) {
-        // just initialize the variable
-        touchMousePressTimestamp = newPressEventTimestamp;
-        doubleClicked = false;
-    } else {
-        ulong timeBetweenPresses = newPressEventTimestamp - touchMousePressTimestamp;
-        ulong doubleClickInterval = static_cast<ulong>(QGuiApplication::styleHints()->
-                mouseDoubleClickInterval());
-        doubleClicked = timeBetweenPresses < doubleClickInterval;
         if (doubleClicked) {
-            touchMousePressTimestamp = 0;
-        } else {
-            touchMousePressTimestamp = newPressEventTimestamp;
+            ulong timeBetweenPresses = newPressEventTimestamp - touchMousePressTimestamp;
+            ulong doubleClickInterval = static_cast<ulong>(QGuiApplication::styleHints()->
+                    mouseDoubleClickInterval());
+            doubleClicked = timeBetweenPresses < doubleClickInterval;
         }
     }
+    if (doubleClicked) {
+        touchMousePressTimestamp = 0;
+    } else {
+        touchMousePressTimestamp = newPressEventTimestamp;
+        touchMousePressPos = newPressPos;
+    }
 
     return doubleClicked;
 }
@@ -707,7 +711,9 @@ bool QQuickWindowPrivate::deliverTouchAsMouse(QQuickItem *item, QQuickPointerEve
                 if (auto pointerEventPoint = pointerEvent->pointById(p.id()))
                     pointerEventPoint->setGrabberItem(item);
 
-                if (checkIfDoubleClicked(event->timestamp())) {
+                if (checkIfDoubleTapped(event->timestamp(), p.screenPos().toPoint())) {
+                    // since we synth the mouse event from from touch, we respect the
+                    // QPlatformTheme::TouchDoubleTapDistance instead of QPlatformTheme::MouseDoubleClickDistance
                     QScopedPointer<QMouseEvent> mouseDoubleClick(touchToMouseEvent(QEvent::MouseButtonDblClick, p, event.data(), item, false));
                     QCoreApplication::sendEvent(item, mouseDoubleClick.data());
                     event->setAccepted(mouseDoubleClick->isAccepted());
@@ -722,6 +728,12 @@ bool QQuickWindowPrivate::deliverTouchAsMouse(QQuickItem *item, QQuickPointerEve
         // Touch point was there before and moved
         } else if (touchMouseDevice == device && p.id() == touchMouseId) {
             if (p.state() & Qt::TouchPointMoved) {
+                if (touchMousePressTimestamp != 0) {
+                    const int doubleTapDistance = QGuiApplicationPrivate::platformTheme()->themeHint(QPlatformTheme::TouchDoubleTapDistance).toInt();
+                    const QPoint moveDelta = p.screenPos().toPoint() - touchMousePressPos;
+                    if (moveDelta.x() >= doubleTapDistance || moveDelta.y() >= doubleTapDistance)
+                        touchMousePressTimestamp = 0;   // Got dragged too far, dismiss the double tap
+                }
                 if (QQuickItem *mouseGrabberItem = q->mouseGrabberItem()) {
                     QScopedPointer<QMouseEvent> me(touchToMouseEvent(QEvent::MouseMove, p, event.data(), mouseGrabberItem, false));
                     QCoreApplication::sendEvent(item, me.data());
diff --git a/src/quick/items/qquickwindow_p.h b/src/quick/items/qquickwindow_p.h
index 5a3807b24f..63760a3b68 100644
--- a/src/quick/items/qquickwindow_p.h
+++ b/src/quick/items/qquickwindow_p.h
@@ -135,8 +135,9 @@ public:
 #endif
     int touchMouseId;
     QQuickPointerDevice *touchMouseDevice;
-    bool checkIfDoubleClicked(ulong newPressEventTimestamp);
+    bool checkIfDoubleTapped(ulong newPressEventTimestamp, QPoint newPressPos);
     ulong touchMousePressTimestamp;
+    QPoint touchMousePressPos;      // in screen coordiantes
     void cancelTouchMouseSynthesis();
 
     // Mouse positions are saved in widget coordinates
diff --git a/src/quick/scenegraph/qsgcontext.cpp b/src/quick/scenegraph/qsgcontext.cpp
index d9ed25c099..53648e352a 100644
--- a/src/quick/scenegraph/qsgcontext.cpp
+++ b/src/quick/scenegraph/qsgcontext.cpp
@@ -393,7 +393,7 @@ QSGTexture *QSGRenderContext::textureForFactory(QQuickTextureFactory *factory, Q
 void QSGRenderContext::textureFactoryDestroyed(QObject *o)
 {
     m_mutex.lock();
-    m_texturesToDelete << m_textures.take(static_cast<QQuickTextureFactory *>(o));
+    m_texturesToDelete << m_textures.take(o);
     m_mutex.unlock();
 }
 
diff --git a/src/quick/scenegraph/qsgcontext_p.h b/src/quick/scenegraph/qsgcontext_p.h
index 6d70d7ef6b..282ce828af 100644
--- a/src/quick/scenegraph/qsgcontext_p.h
+++ b/src/quick/scenegraph/qsgcontext_p.h
@@ -194,7 +194,7 @@ protected:
     QPointer<QSGContext> m_sg;
 
     QMutex m_mutex;
-    QHash<QQuickTextureFactory *, QSGTexture *> m_textures;
+    QHash<QObject *, QSGTexture *> m_textures;
     QSet<QSGTexture *> m_texturesToDelete;
     QHash<QString, QSGDistanceFieldGlyphCache *> m_glyphCaches;
 
diff --git a/src/quick/scenegraph/qsgdefaultdistancefieldglyphcache.cpp b/src/quick/scenegraph/qsgdefaultdistancefieldglyphcache.cpp
index 8121b4559e..9ad0a77318 100644
--- a/src/quick/scenegraph/qsgdefaultdistancefieldglyphcache.cpp
+++ b/src/quick/scenegraph/qsgdefaultdistancefieldglyphcache.cpp
@@ -41,6 +41,7 @@
 
 #include <QtCore/qelapsedtimer.h>
 #include <QtCore/qbuffer.h>
+#include <QtCore/qendian.h>
 #include <QtQml/qqmlfile.h>
 
 #include <QtGui/private/qdistancefield_p.h>
diff --git a/src/quick/scenegraph/qsgdefaultglyphnode_p.h b/src/quick/scenegraph/qsgdefaultglyphnode_p.h
index 37a89c70b9..cfa1c1dad2 100644
--- a/src/quick/scenegraph/qsgdefaultglyphnode_p.h
+++ b/src/quick/scenegraph/qsgdefaultglyphnode_p.h
@@ -53,6 +53,7 @@
 
 #include <private/qsgadaptationlayer_p.h>
 #include <private/qsgbasicglyphnode_p.h>
+#include <qlinkedlist.h>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/quick/util/qquickpropertychanges.cpp b/src/quick/util/qquickpropertychanges.cpp
index d739c8a017..776e7ab59a 100644
--- a/src/quick/util/qquickpropertychanges.cpp
+++ b/src/quick/util/qquickpropertychanges.cpp
@@ -201,14 +201,14 @@ public:
 
     QPointer<QObject> object;
     QList<const QV4::CompiledData::Binding *> bindings;
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> compilationUnit;
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> compilationUnit;
 
     bool decoded : 1;
     bool restore : 1;
     bool isExplicit : 1;
 
     void decode();
-    void decodeBinding(const QString &propertyPrefix, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &qmlUnit, const QV4::CompiledData::Binding *binding);
+    void decodeBinding(const QString &propertyPrefix, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &qmlUnit, const QV4::CompiledData::Binding *binding);
 
     class ExpressionChange {
     public:
@@ -236,7 +236,7 @@ public:
     QQmlProperty property(const QString &);
 };
 
-void QQuickPropertyChangesParser::verifyList(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QV4::CompiledData::Binding *binding)
+void QQuickPropertyChangesParser::verifyList(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QV4::CompiledData::Binding *binding)
 {
     if (binding->type == QV4::CompiledData::Binding::Type_Object) {
         error(compilationUnit->objectAt(binding->value.objectIndex), QQuickPropertyChanges::tr("PropertyChanges does not support creating state-specific objects."));
@@ -266,7 +266,7 @@ void QQuickPropertyChangesPrivate::decode()
     decoded = true;
 }
 
-void QQuickPropertyChangesPrivate::decodeBinding(const QString &propertyPrefix, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QV4::CompiledData::Binding *binding)
+void QQuickPropertyChangesPrivate::decodeBinding(const QString &propertyPrefix, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QV4::CompiledData::Binding *binding)
 {
     Q_Q(QQuickPropertyChanges);
 
@@ -314,7 +314,7 @@ void QQuickPropertyChangesPrivate::decodeBinding(const QString &propertyPrefix,
         QQmlBinding::Identifier id = QQmlBinding::Invalid;
 
         if (!binding->isTranslationBinding()) {
-            expression = binding->valueAsString(compilationUnit.data());
+            expression = compilationUnit->bindingValueAsString(binding);
             id = binding->value.compiledScriptIndex;
         }
         expressions << ExpressionChange(propertyName, binding, id, expression, url, line, column);
@@ -328,10 +328,10 @@ void QQuickPropertyChangesPrivate::decodeBinding(const QString &propertyPrefix,
     case QV4::CompiledData::Binding::Type_TranslationById:
         Q_UNREACHABLE();
     case QV4::CompiledData::Binding::Type_String:
-        var = binding->valueAsString(compilationUnit.data());
+        var = compilationUnit->bindingValueAsString(binding);
         break;
     case QV4::CompiledData::Binding::Type_Number:
-        var = binding->valueAsNumber(compilationUnit->constants);
+        var = compilationUnit->bindingValueAsNumber(binding);
         break;
     case QV4::CompiledData::Binding::Type_Boolean:
         var = binding->valueAsBoolean();
@@ -346,13 +346,13 @@ void QQuickPropertyChangesPrivate::decodeBinding(const QString &propertyPrefix,
     properties << qMakePair(propertyName, var);
 }
 
-void QQuickPropertyChangesParser::verifyBindings(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &props)
+void QQuickPropertyChangesParser::verifyBindings(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &props)
 {
     for (int ii = 0; ii < props.count(); ++ii)
         verifyList(compilationUnit, props.at(ii));
 }
 
-void QQuickPropertyChangesParser::applyBindings(QObject *obj, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings)
+void QQuickPropertyChangesParser::applyBindings(QObject *obj, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings)
 {
     QQuickPropertyChangesPrivate *p =
         static_cast<QQuickPropertyChangesPrivate *>(QObjectPrivate::get(obj));
diff --git a/src/quick/util/qquickpropertychanges_p.h b/src/quick/util/qquickpropertychanges_p.h
index 74fe511d6e..82a6ebffac 100644
--- a/src/quick/util/qquickpropertychanges_p.h
+++ b/src/quick/util/qquickpropertychanges_p.h
@@ -101,10 +101,10 @@ public:
     QQuickPropertyChangesParser()
     : QQmlCustomParser(AcceptsAttachedProperties) {}
 
-    void verifyList(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QV4::CompiledData::Binding *binding);
+    void verifyList(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QV4::CompiledData::Binding *binding);
 
-    void verifyBindings(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &props) override;
-    void applyBindings(QObject *obj, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings) override;
+    void verifyBindings(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &props) override;
+    void applyBindings(QObject *obj, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings) override;
 };
 
 
diff --git a/src/quick/util/qquickstategroup.cpp b/src/quick/util/qquickstategroup.cpp
index d8daec2f07..b53949d21c 100644
--- a/src/quick/util/qquickstategroup.cpp
+++ b/src/quick/util/qquickstategroup.cpp
@@ -130,6 +130,8 @@ QQuickStateGroup::~QQuickStateGroup()
     Q_D(const QQuickStateGroup);
     for (int i = 0; i < d->states.count(); ++i)
         d->states.at(i)->setStateGroup(nullptr);
+    if (d->nullState)
+        d->nullState->setStateGroup(nullptr);
 }
 
 QList<QQuickState *> QQuickStateGroup::states() const
diff --git a/src/src.pro b/src/src.pro
index bd634247e7..b1e0a72c9f 100644
--- a/src/src.pro
+++ b/src/src.pro
@@ -7,6 +7,8 @@ SUBDIRS += \
     qml \
     qmlmodels
 
+qtConfig(qml-worker-script): \
+    SUBDIRS += qmlworkerscript
 
 qtHaveModule(gui):qtConfig(qml-animation) {
     SUBDIRS += \
diff --git a/sync.profile b/sync.profile
index b6a1825eed..ec880f2d67 100644
--- a/sync.profile
+++ b/sync.profile
@@ -8,6 +8,7 @@
     "QtPacketProtocol" => "$basedir/src/plugins/qmltooling/packetprotocol",
     "QtQmlDebug" => "$basedir/src/qmldebug",
     "QtQmlModels" => "$basedir/src/qmlmodels",
+    "QtQmlWorkerScript" => "$basedir/src/qmlworkerscript",
 );
 %inject_headers = (
     "$basedir/src/qml" => [ "^qqmljsgrammar_p.h", "^qqmljsparser_p.h" ],
diff --git a/tests/auto/qml/ecmascripttests/qjstest/test262runner.cpp b/tests/auto/qml/ecmascripttests/qjstest/test262runner.cpp
index cbe3be2e70..33efcb4da4 100644
--- a/tests/auto/qml/ecmascripttests/qjstest/test262runner.cpp
+++ b/tests/auto/qml/ecmascripttests/qjstest/test262runner.cpp
@@ -509,7 +509,7 @@ static bool executeTest(const QByteArray &data, bool runAsModule = false, const
         QVector<QUrl> modulesToLoad = { rootModuleUrl };
         while (!modulesToLoad.isEmpty()) {
             QUrl url = modulesToLoad.takeFirst();
-            QQmlRefPointer<QV4::CompiledData::CompilationUnit> module;
+            QQmlRefPointer<QV4::ExecutableCompilationUnit> module;
 
             QFile f(url.toLocalFile());
             if (f.open(QIODevice::ReadOnly)) {
diff --git a/tests/auto/qml/qmldiskcache/tst_qmldiskcache.cpp b/tests/auto/qml/qmldiskcache/tst_qmldiskcache.cpp
index e86b7bf5fe..c215e9620d 100644
--- a/tests/auto/qml/qmldiskcache/tst_qmldiskcache.cpp
+++ b/tests/auto/qml/qmldiskcache/tst_qmldiskcache.cpp
@@ -33,6 +33,7 @@
 #include <private/qv4engine_p.h>
 #include <private/qv4codegen_p.h>
 #include <private/qqmlcomponent_p.h>
+#include <private/qv4executablecompilationunit_p.h>
 #include <QQmlComponent>
 #include <QQmlEngine>
 #include <QQmlFileSelector>
@@ -118,7 +119,8 @@ struct TestCompiler
     {
         closeMapping();
         testFilePath = baseDirectory + QStringLiteral("/test.qml");
-        cacheFilePath = QV4::CompiledData::CompilationUnit::localCacheFilePath(QUrl::fromLocalFile(testFilePath));
+        cacheFilePath = QV4::ExecutableCompilationUnit::localCacheFilePath(
+                QUrl::fromLocalFile(testFilePath));
         mappedFile.setFileName(cacheFilePath);
     }
 
@@ -185,8 +187,10 @@ struct TestCompiler
 
     bool verify()
     {
-        QQmlRefPointer<QV4::CompiledData::CompilationUnit> unit = QV4::Compiler::Codegen::createUnitForLoading();
-        return unit->loadFromDisk(QUrl::fromLocalFile(testFilePath), QFileInfo(testFilePath).lastModified(), &lastErrorString);
+        QQmlRefPointer<QV4::ExecutableCompilationUnit> unit
+                = QV4::ExecutableCompilationUnit::create();
+        return unit->loadFromDisk(QUrl::fromLocalFile(testFilePath),
+                                  QFileInfo(testFilePath).lastModified(), &lastErrorString);
     }
 
     void closeMapping()
@@ -263,8 +267,9 @@ void tst_qmldiskcache::loadLocalAsFallback()
         f.write(reinterpret_cast<const char *>(&unit), sizeof(unit));
     }
 
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> unit = QV4::Compiler::Codegen::createUnitForLoading();
-    bool loaded = unit->loadFromDisk(QUrl::fromLocalFile(testCompiler.testFilePath), QFileInfo(testCompiler.testFilePath).lastModified(),
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> unit = QV4::ExecutableCompilationUnit::create();
+    bool loaded = unit->loadFromDisk(QUrl::fromLocalFile(testCompiler.testFilePath),
+                                     QFileInfo(testCompiler.testFilePath).lastModified(),
                                      &testCompiler.lastErrorString);
     QVERIFY2(loaded, qPrintable(testCompiler.lastErrorString));
     QCOMPARE(unit->objectCount(), 1);
@@ -323,7 +328,10 @@ void tst_qmldiskcache::regenerateAfterChange()
         const QV4::CompiledData::Object *obj = qmlUnit->objectAt(0);
         QCOMPARE(quint32(obj->nBindings), quint32(2));
         QCOMPARE(quint32(obj->bindingTable()->type), quint32(QV4::CompiledData::Binding::Type_Number));
-        QCOMPARE(obj->bindingTable()->valueAsNumber(reinterpret_cast<const QV4::Value *>(testUnit->constants())), double(42));
+
+        QCOMPARE(reinterpret_cast<const QV4::Value *>(testUnit->constants())
+                         [obj->bindingTable()->value.constantValueIndex].doubleValue(),
+                 double(42));
 
         QCOMPARE(quint32(testUnit->functionTableSize), quint32(1));
 
@@ -572,7 +580,8 @@ void tst_qmldiskcache::fileSelectors()
         QVERIFY(!obj.isNull());
         QCOMPARE(obj->property("value").toInt(), 42);
 
-        QFile cacheFile(QV4::CompiledData::CompilationUnit::localCacheFilePath(QUrl::fromLocalFile(testFilePath)));
+        QFile cacheFile(QV4::ExecutableCompilationUnit::localCacheFilePath(
+                QUrl::fromLocalFile(testFilePath)));
         QVERIFY2(cacheFile.exists(), qPrintable(cacheFile.fileName()));
     }
 
@@ -587,7 +596,8 @@ void tst_qmldiskcache::fileSelectors()
         QVERIFY(!obj.isNull());
         QCOMPARE(obj->property("value").toInt(), 100);
 
-        QFile cacheFile(QV4::CompiledData::CompilationUnit::localCacheFilePath(QUrl::fromLocalFile(selectedTestFilePath)));
+        QFile cacheFile(QV4::ExecutableCompilationUnit::localCacheFilePath(
+                QUrl::fromLocalFile(selectedTestFilePath)));
         QVERIFY2(cacheFile.exists(), qPrintable(cacheFile.fileName()));
     }
 }
@@ -737,7 +747,8 @@ void tst_qmldiskcache::stableOrderOfDependentCompositeTypes()
     QVERIFY2(firstDependentTypeClassName.contains("QMLTYPE"), firstDependentTypeClassName.constData());
     QVERIFY2(secondDependentTypeClassName.contains("QMLTYPE"), secondDependentTypeClassName.constData());
 
-    const QString testFileCachePath = QV4::CompiledData::CompilationUnit::localCacheFilePath(QUrl::fromLocalFile(testFilePath));
+    const QString testFileCachePath = QV4::ExecutableCompilationUnit::localCacheFilePath(
+            QUrl::fromLocalFile(testFilePath));
     QVERIFY(QFile::exists(testFileCachePath));
     QDateTime initialCacheTimeStamp = QFileInfo(testFileCachePath).lastModified();
 
@@ -815,7 +826,8 @@ void tst_qmldiskcache::singletonDependency()
         QCOMPARE(obj->property("value").toInt(), 42);
     }
 
-    const QString testFileCachePath = QV4::CompiledData::CompilationUnit::localCacheFilePath(QUrl::fromLocalFile(testFilePath));
+    const QString testFileCachePath = QV4::ExecutableCompilationUnit::localCacheFilePath(
+            QUrl::fromLocalFile(testFilePath));
     QVERIFY(QFile::exists(testFileCachePath));
     QDateTime initialCacheTimeStamp = QFileInfo(testFileCachePath).lastModified();
 
@@ -872,7 +884,8 @@ void tst_qmldiskcache::cppRegisteredSingletonDependency()
         QCOMPARE(value.toInt(), 42);
     }
 
-    const QString testFileCachePath = QV4::CompiledData::CompilationUnit::localCacheFilePath(QUrl::fromLocalFile(testFilePath));
+    const QString testFileCachePath = QV4::ExecutableCompilationUnit::localCacheFilePath(
+            QUrl::fromLocalFile(testFilePath));
     QVERIFY(QFile::exists(testFileCachePath));
     QDateTime initialCacheTimeStamp = QFileInfo(testFileCachePath).lastModified();
 
diff --git a/tests/auto/qml/qqmlbinding/data/restoreBinding2.qml b/tests/auto/qml/qqmlbinding/data/restoreBinding2.qml
new file mode 100644
index 0000000000..b42f975fe0
--- /dev/null
+++ b/tests/auto/qml/qqmlbinding/data/restoreBinding2.qml
@@ -0,0 +1,55 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:GPL-EXCEPT$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+import QtQuick 2.0
+import QtQml 2.14
+
+Rectangle {
+    height: 400
+    width: 400
+
+    Rectangle {
+        property bool when: true
+
+        id: myItem
+        objectName:  "myItem"
+        height: 300
+        width: 200
+    }
+
+    property var boundValue: 100
+
+    Binding {
+        restoreMode: Binding.RestoreValue
+        objectName: "theBinding"
+        target: myItem
+        property: "height"
+        when: myItem.when
+        value: boundValue
+    }
+}
diff --git a/tests/auto/qml/qqmlbinding/data/restoreBinding3.qml b/tests/auto/qml/qqmlbinding/data/restoreBinding3.qml
new file mode 100644
index 0000000000..1f63457ab6
--- /dev/null
+++ b/tests/auto/qml/qqmlbinding/data/restoreBinding3.qml
@@ -0,0 +1,56 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:GPL-EXCEPT$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+import QtQuick 2.0
+import QtQml 2.14
+
+Rectangle {
+    height: 400
+    width: 400
+
+    Rectangle {
+        property bool when: true
+
+        id: myItem
+        objectName:  "myItem"
+        height: 300
+        width: 200
+        property var foo: 42
+    }
+
+    property var boundValue: 13
+
+    Binding {
+        restoreMode: Binding.RestoreBindingOrValue
+        objectName: "theBinding"
+        target: myItem
+        property: "foo"
+        when: myItem.when
+        value: boundValue
+    }
+}
diff --git a/tests/auto/qml/qqmlbinding/data/restoreBinding4.qml b/tests/auto/qml/qqmlbinding/data/restoreBinding4.qml
new file mode 100644
index 0000000000..f34c3b40cf
--- /dev/null
+++ b/tests/auto/qml/qqmlbinding/data/restoreBinding4.qml
@@ -0,0 +1,59 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:GPL-EXCEPT$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+import QtQuick 2.0
+import QtQml 2.14
+
+Rectangle {
+    height: 400
+    width: 400
+
+    Rectangle {
+        property bool when: true
+
+        id: myItem
+        objectName:  "myItem"
+        height: 300
+        width: 200
+        property var foo: original
+        property bool fooCheck: foo === original && foo.bar() === 42
+    }
+
+    property var original: ({ bar: function() { return 42 } })
+
+    property var boundValue: 13
+
+    Binding {
+        restoreMode: Binding.RestoreBinding
+        objectName: "theBinding"
+        target: myItem
+        property: "foo"
+        when: myItem.when
+        value: boundValue
+    }
+}
diff --git a/tests/auto/qml/qqmlbinding/tst_qqmlbinding.cpp b/tests/auto/qml/qqmlbinding/tst_qqmlbinding.cpp
index 34cf21024d..717fd5dbd1 100644
--- a/tests/auto/qml/qqmlbinding/tst_qqmlbinding.cpp
+++ b/tests/auto/qml/qqmlbinding/tst_qqmlbinding.cpp
@@ -42,6 +42,9 @@ private slots:
     void binding();
     void whenAfterValue();
     void restoreBinding();
+    void restoreBindingValue();
+    void restoreBindingVarValue();
+    void restoreBindingJSValue();
     void restoreBindingWithLoop();
     void restoreBindingWithoutCrash();
     void deletedObject();
@@ -134,6 +137,78 @@ void tst_qqmlbinding::restoreBinding()
     delete rect;
 }
 
+void tst_qqmlbinding::restoreBindingValue()
+{
+    QQmlEngine engine;
+    QQmlComponent c(&engine, testFileUrl("restoreBinding2.qml"));
+    QScopedPointer<QQuickRectangle> rect(qobject_cast<QQuickRectangle*>(c.create()));
+    QVERIFY(!rect.isNull());
+
+    auto myItem = qobject_cast<QQuickRectangle*>(rect->findChild<QQuickRectangle*>("myItem"));
+    QVERIFY(myItem != nullptr);
+
+    QCOMPARE(myItem->height(), 100);
+    myItem->setProperty("when", QVariant(false));
+    QCOMPARE(myItem->height(), 300); // make sure the original value was restored
+
+    myItem->setProperty("when", QVariant(true));
+    QCOMPARE(myItem->height(), 100); // make sure the value specified in Binding is set
+    rect->setProperty("boundValue", 200);
+    QCOMPARE(myItem->height(), 200); // make sure the changed binding value is set
+    myItem->setProperty("when", QVariant(false));
+    // make sure that the original value is back, not e.g. the value from before the
+    // change (i.e. 100)
+    QCOMPARE(myItem->height(), 300);
+}
+
+void tst_qqmlbinding::restoreBindingVarValue()
+{
+    QQmlEngine engine;
+    QQmlComponent c(&engine, testFileUrl("restoreBinding3.qml"));
+    QScopedPointer<QQuickRectangle> rect(qobject_cast<QQuickRectangle*>(c.create()));
+    QVERIFY(!rect.isNull());
+
+    auto myItem = qobject_cast<QQuickRectangle*>(rect->findChild<QQuickRectangle*>("myItem"));
+    QVERIFY(myItem != nullptr);
+
+    QCOMPARE(myItem->property("foo"), 13);
+    myItem->setProperty("when", QVariant(false));
+    QCOMPARE(myItem->property("foo"), 42); // make sure the original value was restored
+
+    myItem->setProperty("when", QVariant(true));
+    QCOMPARE(myItem->property("foo"), 13); // make sure the value specified in Binding is set
+    rect->setProperty("boundValue", 31337);
+    QCOMPARE(myItem->property("foo"), 31337); // make sure the changed binding value is set
+    myItem->setProperty("when", QVariant(false));
+    // make sure that the original value is back, not e.g. the value from before the
+    // change (i.e. 100)
+    QCOMPARE(myItem->property("foo"), 42);
+}
+
+void tst_qqmlbinding::restoreBindingJSValue()
+{
+    QQmlEngine engine;
+    QQmlComponent c(&engine, testFileUrl("restoreBinding4.qml"));
+    QScopedPointer<QQuickRectangle> rect(qobject_cast<QQuickRectangle*>(c.create()));
+    QVERIFY(!rect.isNull());
+
+    auto myItem = qobject_cast<QQuickRectangle*>(rect->findChild<QQuickRectangle*>("myItem"));
+    QVERIFY(myItem != nullptr);
+
+    QCOMPARE(myItem->property("fooCheck"), false);
+    myItem->setProperty("when", QVariant(false));
+    QCOMPARE(myItem->property("fooCheck"), true); // make sure the original value was restored
+
+    myItem->setProperty("when", QVariant(true));
+    QCOMPARE(myItem->property("fooCheck"), false); // make sure the value specified in Binding is set
+    rect->setProperty("boundValue", 31337);
+    QCOMPARE(myItem->property("fooCheck"), false); // make sure the changed binding value is set
+    myItem->setProperty("when", QVariant(false));
+    // make sure that the original value is back, not e.g. the value from before the change
+    QCOMPARE(myItem->property("fooCheck"), true);
+
+}
+
 void tst_qqmlbinding::restoreBindingWithLoop()
 {
     QQmlEngine engine;
diff --git a/tests/auto/qml/qqmlengine/data/CachedGetterLookup.qml b/tests/auto/qml/qqmlengine/data/CachedGetterLookup.qml
new file mode 100644
index 0000000000..1a2a7ff341
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/CachedGetterLookup.qml
@@ -0,0 +1,20 @@
+import QtQuick 2.12
+
+QtObject {
+    Component.onCompleted: {
+        // create getter
+        var getFoo = function(o) { return o.foo; }
+
+        // create two diffrent shapes for x,y
+        var x = { foo:1 , bar:2 }
+        var y = { bar:2 , foo:1 }
+
+        // initialize inline cache with getFoo
+        getFoo(x);
+        getFoo(y);
+
+        // hit getter lookup with string "crash"
+        getFoo('crash');
+    }
+}
+
diff --git a/tests/auto/qml/qqmlengine/tst_qqmlengine.cpp b/tests/auto/qml/qqmlengine/tst_qqmlengine.cpp
index b9cb6b70d2..0cb6753020 100644
--- a/tests/auto/qml/qqmlengine/tst_qqmlengine.cpp
+++ b/tests/auto/qml/qqmlengine/tst_qqmlengine.cpp
@@ -81,6 +81,7 @@ private slots:
     void cppSignalAndEval();
     void singletonInstance();
     void aggressiveGc();
+    void cachedGetterLookup_qtbug_75335();
 
 public slots:
     QObject *createAQObjectForOwnershipTest ()
@@ -1056,6 +1057,16 @@ void tst_qqmlengine::aggressiveGc()
     qputenv("QV4_MM_AGGRESSIVE_GC", origAggressiveGc);
 }
 
+void tst_qqmlengine::cachedGetterLookup_qtbug_75335()
+{
+    QQmlEngine engine;
+    const QUrl testUrl = testFileUrl("CachedGetterLookup.qml");
+    QQmlComponent component(&engine, testUrl);
+    QVERIFY(component.isReady());
+    QScopedPointer<QObject> object(component.create());
+    QVERIFY(object != nullptr);
+}
+
 QTEST_MAIN(tst_qqmlengine)
 
 #include "tst_qqmlengine.moc"
diff --git a/tests/auto/qml/qqmllanguage/data/bareQmlImport.errors.txt b/tests/auto/qml/qqmllanguage/data/bareQmlImport.errors.txt
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/tests/auto/qml/qqmllanguage/data/bareQmlImport.errors.txt
diff --git a/tests/auto/qml/qqmllanguage/data/bareQmlImport.qml b/tests/auto/qml/qqmllanguage/data/bareQmlImport.qml
new file mode 100644
index 0000000000..3567cdb5a3
--- /dev/null
+++ b/tests/auto/qml/qqmllanguage/data/bareQmlImport.qml
@@ -0,0 +1,6 @@
+import QML 1.0
+QtObject {
+    property Component component: Component {
+        QtObject {}
+    }
+}
diff --git a/tests/auto/qml/qqmllanguage/testtypes.cpp b/tests/auto/qml/qqmllanguage/testtypes.cpp
index f9a6ee8e5a..d6215307bf 100644
--- a/tests/auto/qml/qqmllanguage/testtypes.cpp
+++ b/tests/auto/qml/qqmllanguage/testtypes.cpp
@@ -125,7 +125,7 @@ QVariant myCustomVariantTypeConverter(const QString &data)
 }
 
 
-void CustomBindingParser::applyBindings(QObject *object, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings)
+void CustomBindingParser::applyBindings(QObject *object, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings)
 {
     CustomBinding *customBinding = qobject_cast<CustomBinding*>(object);
     Q_ASSERT(customBinding);
@@ -154,7 +154,7 @@ void CustomBinding::componentComplete()
     }
 }
 
-void EnumSupportingCustomParser::verifyBindings(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings)
+void EnumSupportingCustomParser::verifyBindings(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &compilationUnit, const QList<const QV4::CompiledData::Binding *> &bindings)
 {
     if (bindings.count() != 1) {
         error(bindings.first(), QStringLiteral("Custom parser invoked incorrectly for unit test"));
@@ -184,7 +184,7 @@ void EnumSupportingCustomParser::verifyBindings(const QQmlRefPointer<QV4::Compil
     }
 }
 
-void SimpleObjectCustomParser::applyBindings(QObject *object, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &bindings)
+void SimpleObjectCustomParser::applyBindings(QObject *object, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &bindings)
 {
     SimpleObjectWithCustomParser *o = qobject_cast<SimpleObjectWithCustomParser*>(object);
     Q_ASSERT(o);
diff --git a/tests/auto/qml/qqmllanguage/testtypes.h b/tests/auto/qml/qqmllanguage/testtypes.h
index bb6e9582c2..0618d2b20f 100644
--- a/tests/auto/qml/qqmllanguage/testtypes.h
+++ b/tests/auto/qml/qqmllanguage/testtypes.h
@@ -781,15 +781,15 @@ class MyCustomParserType : public QObject
 class MyCustomParserTypeParser : public QQmlCustomParser
 {
 public:
-    virtual void verifyBindings(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &) {}
-    virtual void applyBindings(QObject *, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &) {}
+    virtual void verifyBindings(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &) {}
+    virtual void applyBindings(QObject *, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &) {}
 };
 
 class EnumSupportingCustomParser : public QQmlCustomParser
 {
 public:
-    virtual void verifyBindings(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &);
-    virtual void applyBindings(QObject *, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &) {}
+    virtual void verifyBindings(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &);
+    virtual void applyBindings(QObject *, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &) {}
 };
 
 class MyParserStatus : public QObject, public QQmlParserStatus
@@ -1275,15 +1275,15 @@ public:
     void setTarget(QObject *newTarget) { m_target = newTarget; }
 
     QPointer<QObject> m_target;
-    QQmlRefPointer<QV4::CompiledData::CompilationUnit> compilationUnit;
+    QQmlRefPointer<QV4::ExecutableCompilationUnit> compilationUnit;
     QList<const QV4::CompiledData::Binding*> bindings;
     QByteArray m_bindingData;
 };
 
 class CustomBindingParser : public QQmlCustomParser
 {
-    virtual void verifyBindings(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &) {}
-    virtual void applyBindings(QObject *, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &);
+    virtual void verifyBindings(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &) {}
+    virtual void applyBindings(QObject *, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &);
 };
 
 class SimpleObjectWithCustomParser : public QObject
@@ -1328,8 +1328,8 @@ private:
 
 class SimpleObjectCustomParser : public QQmlCustomParser
 {
-    virtual void verifyBindings(const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &) {}
-    virtual void applyBindings(QObject *, const QQmlRefPointer<QV4::CompiledData::CompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &);
+    virtual void verifyBindings(const QQmlRefPointer<QV4::ExecutableCompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &) {}
+    virtual void applyBindings(QObject *, const QQmlRefPointer<QV4::ExecutableCompilationUnit> &, const QList<const QV4::CompiledData::Binding *> &);
 };
 
 class RootObjectInCreationTester : public QObject
diff --git a/tests/auto/qml/qqmllanguage/tst_qqmllanguage.cpp b/tests/auto/qml/qqmllanguage/tst_qqmllanguage.cpp
index b97c75e2ce..8cbb39974e 100644
--- a/tests/auto/qml/qqmllanguage/tst_qqmllanguage.cpp
+++ b/tests/auto/qml/qqmllanguage/tst_qqmllanguage.cpp
@@ -620,6 +620,8 @@ void tst_qqmllanguage::errors_data()
 
     QTest::newRow("fuzzed.1") << "fuzzed.1.qml" << "fuzzed.1.errors.txt" << false;
     QTest::newRow("fuzzed.2") << "fuzzed.2.qml" << "fuzzed.2.errors.txt" << false;
+
+    QTest::newRow("bareQmlImport") << "bareQmlImport.qml" << "bareQmlImport.errors.txt" << false;
 }
 
 
@@ -2223,7 +2225,7 @@ void tst_qqmllanguage::scriptStringWithoutSourceCode()
         QV4::CompiledData::Unit *qmlUnit = reinterpret_cast<QV4::CompiledData::Unit *>(malloc(readOnlyQmlUnit->unitSize));
         memcpy(qmlUnit, readOnlyQmlUnit, readOnlyQmlUnit->unitSize);
         qmlUnit->flags &= ~QV4::CompiledData::Unit::StaticData;
-        QQmlRefPointer<QV4::CompiledData::CompilationUnit> compilationUnit = td->compilationUnit();
+        QQmlRefPointer<QV4::ExecutableCompilationUnit> compilationUnit = td->compilationUnit();
         compilationUnit->setUnitData(qmlUnit);
 
         const QV4::CompiledData::Object *rootObject = compilationUnit->objectAt(/*root object*/0);
@@ -2233,9 +2235,9 @@ void tst_qqmllanguage::scriptStringWithoutSourceCode()
             const QV4::CompiledData::Binding *binding = rootObject->bindingTable() + i;
             if (compilationUnit->stringAt(binding->propertyNameIndex) != QString("scriptProperty"))
                 continue;
-            QCOMPARE(binding->valueAsScriptString(compilationUnit.data()), QString("intProperty"));
+            QCOMPARE(compilationUnit->bindingValueAsScriptString(binding), QString("intProperty"));
             const_cast<QV4::CompiledData::Binding*>(binding)->stringIndex = 0; // empty string index
-            QVERIFY(binding->valueAsScriptString(compilationUnit.data()).isEmpty());
+            QVERIFY(compilationUnit->bindingValueAsScriptString(binding).isEmpty());
             break;
         }
         QVERIFY(i < rootObject->nBindings);
diff --git a/tests/auto/qml/qqmltranslation/tst_qqmltranslation.cpp b/tests/auto/qml/qqmltranslation/tst_qqmltranslation.cpp
index 809a9bd9db..3b17df9872 100644
--- a/tests/auto/qml/qqmltranslation/tst_qqmltranslation.cpp
+++ b/tests/auto/qml/qqmltranslation/tst_qqmltranslation.cpp
@@ -85,7 +85,8 @@ void tst_qqmltranslation::translation()
                              << QStringLiteral("disambiguation")
                              << QStringLiteral("singular") << QStringLiteral("plural");
 
-        const QV4::CompiledData::Object *rootObject = compilationUnit->objectAt(/*root object*/0);
+        const QV4::CompiledData::Object *rootObject
+                = compilationUnit->qmlData->objectAt(/*root object*/0);
         const QV4::CompiledData::Binding *binding = rootObject->bindingTable();
         for (quint32 i = 0; i < rootObject->nBindings; ++i, ++binding) {
             const QString propertyName = compilationUnit->stringAt(binding->propertyNameIndex);
@@ -139,7 +140,8 @@ void tst_qqmltranslation::idTranslation()
         QV4::CompiledData::CompilationUnit *compilationUnit = typeData->compilationUnit();
         QVERIFY(compilationUnit);
 
-        const QV4::CompiledData::Object *rootObject = compilationUnit->objectAt(/*root object*/0);
+        const QV4::CompiledData::Object *rootObject
+                = compilationUnit->qmlData->objectAt(/*root object*/0);
         const QV4::CompiledData::Binding *binding = rootObject->bindingTable();
         for (quint32 i = 0; i < rootObject->nBindings; ++i, ++binding) {
             const QString propertyName = compilationUnit->stringAt(binding->propertyNameIndex);
diff --git a/tests/auto/qml/qquickworkerscript/qquickworkerscript.pro b/tests/auto/qml/qquickworkerscript/qquickworkerscript.pro
index be8b9089a2..f58fd4543f 100644
--- a/tests/auto/qml/qquickworkerscript/qquickworkerscript.pro
+++ b/tests/auto/qml/qquickworkerscript/qquickworkerscript.pro
@@ -8,4 +8,4 @@ include (../../shared/util.pri)
 
 TESTDATA = data/*
 
-QT += core-private gui-private  qml-private testlib
+QT += core-private gui-private qml-private testlib qmlworkerscript-private
diff --git a/tests/auto/qmltest/statemachine/tst_parallelmachine.qml b/tests/auto/qmltest/statemachine/tst_parallelmachine.qml
index be7d73fbe5..eb996c7718 100644
--- a/tests/auto/qmltest/statemachine/tst_parallelmachine.qml
+++ b/tests/auto/qmltest/statemachine/tst_parallelmachine.qml
@@ -32,25 +32,29 @@ import QtQml.StateMachine 1.0
 TestCase {
     StateMachine {
         id: myStateMachine
-        childMode: State.ParallelStates
+        initialState: rootState
         State {