Add specialized instructions for loading undefined, null and ints

Change-Id: Iab0b77328f5756972ef6eff82c0041b184290a32
Reviewed-by: Erik Verbruggen <erik.verbruggen@qt.io>

4 files changed, 60 insertions, 3 deletions

diff --git a/src/qml/compiler/qv4codegen.cpp b/src/qml/compiler/qv4codegen.cpp
index a91a6e62e0..6492bb6028 100644
--- a/src/qml/compiler/qv4codegen.cpp
+++ b/src/qml/compiler/qv4codegen.cpp
@@ -3001,9 +3001,28 @@ void Codegen::Reference::loadInAccumulator() const
     case Accumulator:
         return;
     case Const: {
-        Instruction::LoadConst load;
-        load.index = codegen->registerConstant(constant);
-        codegen->bytecodeGenerator->addInstruction(load);
+        if (constant == Encode::null()) {
+            Instruction::LoadNull load;
+            codegen->bytecodeGenerator->addInstruction(load);
+        } else if (constant == Encode::undefined()) {
+            Instruction::LoadUndefined load;
+            codegen->bytecodeGenerator->addInstruction(load);
+        } else {
+            Value p = Primitive::fromReturnedValue(constant);
+            if (p.isNumber()) {
+                double d = p.asDouble();
+                int i = static_cast<int>(d);
+                if (d == i && (d != 0 || !std::signbit(d))) {
+                    Instruction::LoadInt load;
+                    load.value = Primitive::fromReturnedValue(constant).toInt32();
+                    codegen->bytecodeGenerator->addInstruction(load);
+                    return;
+                }
+            }
+            Instruction::LoadConst load;
+            load.index = codegen->registerConstant(constant);
+            codegen->bytecodeGenerator->addInstruction(load);
+        }
     } return;
     case StackSlot: {
         Instruction::LoadReg load;
diff --git a/src/qml/compiler/qv4instr_moth.cpp b/src/qml/compiler/qv4instr_moth.cpp
index ed2f556e01..b885db30bf 100644
--- a/src/qml/compiler/qv4instr_moth.cpp
+++ b/src/qml/compiler/qv4instr_moth.cpp
@@ -133,6 +133,16 @@ void dumpBytecode(const char *code, int len, int nFormals)
             d << "C" << instr.index;
         MOTH_END_INSTR(LoadConst)
 
+        MOTH_BEGIN_INSTR(LoadNull)
+        MOTH_END_INSTR(LoadNull)
+
+        MOTH_BEGIN_INSTR(LoadUndefined)
+        MOTH_END_INSTR(LoadUndefined)
+
+        MOTH_BEGIN_INSTR(LoadInt)
+            d << instr.value;
+        MOTH_END_INSTR(LoadInt)
+
         MOTH_BEGIN_INSTR(MoveConst)
             d << instr.destTemp.dump(nFormals) << ", C" << instr.constIndex;
         MOTH_END_INSTR(MoveConst)
diff --git a/src/qml/compiler/qv4instr_moth_p.h b/src/qml/compiler/qv4instr_moth_p.h
index d07e44c41b..df1c9ddef7 100644
--- a/src/qml/compiler/qv4instr_moth_p.h
+++ b/src/qml/compiler/qv4instr_moth_p.h
@@ -72,6 +72,9 @@ QT_BEGIN_NAMESPACE
     F(Ret, ret) \
     MOTH_DEBUG_INSTR(F) \
     F(LoadConst, loadConst) \
+    F(LoadNull, loadNull) \
+    F(LoadUndefined, loadUndefined) \
+    F(LoadInt, loadInt) \
     F(MoveConst, moveConst) \
     F(LoadReg, loadReg) \
     F(StoreReg, storeReg) \
@@ -266,6 +269,16 @@ union Instr
         MOTH_INSTR_HEADER
         int index;
     };
+    struct instr_loadNull {
+        MOTH_INSTR_HEADER
+    };
+    struct instr_loadUndefined {
+        MOTH_INSTR_HEADER
+    };
+    struct instr_loadInt {
+        MOTH_INSTR_HEADER
+        int value;
+    };
     struct instr_moveConst {
         MOTH_INSTR_HEADER
         int constIndex;
@@ -711,6 +724,9 @@ union Instr
     instr_line line;
     instr_debug debug;
     instr_loadConst loadConst;
+    instr_loadNull loadNull;
+    instr_loadUndefined loadUndefined;
+    instr_loadInt loadInt;
     instr_moveConst moveConst;
     instr_loadReg loadReg;
     instr_storeReg storeReg;
diff --git a/src/qml/jsruntime/qv4vme_moth.cpp b/src/qml/jsruntime/qv4vme_moth.cpp
index b17341e5e5..72a707fe51 100644
--- a/src/qml/jsruntime/qv4vme_moth.cpp
+++ b/src/qml/jsruntime/qv4vme_moth.cpp
@@ -468,6 +468,18 @@ QV4::ReturnedValue VME::exec(const FunctionObject *jsFunction, CallData *callDat
         accumulator = constant(function, instr.index);
     MOTH_END_INSTR(LoadConst)
 
+    MOTH_BEGIN_INSTR(LoadNull)
+        accumulator = Encode::null();
+    MOTH_END_INSTR(LoadNull)
+
+    MOTH_BEGIN_INSTR(LoadUndefined)
+        accumulator = Encode::undefined();
+    MOTH_END_INSTR(LoadUndefined)
+
+    MOTH_BEGIN_INSTR(LoadInt)
+        accumulator = Encode(instr.value);
+    MOTH_END_INSTR(LoadInt)
+
     MOTH_BEGIN_INSTR(MoveConst)
         STACK_VALUE(instr.destTemp) = constant(function, instr.constIndex);
     MOTH_END_INSTR(MoveConst)