Fix run-time string handling with regards to the new heap

Changed runtimeStrings to be an array of Heap::String pointers instead of
indirect String pointers. Later that member along with other GC related members
will go into a managed subclass. Meanwhile the generated code no more loads
String pointers directly but just passes the index into the run-time strings to
the run-time functions, which in turn will load the heap string into a scoped
string.

Also replaced the template<T> Value::operator=(T *m) with a non-template
overload that takes a Managed *, in order to help the compiler choose the
non-template operator=(Heap::Base *) overload. This allows removing a bunch
of Value::fromHeapObject calls.

Change-Id: I20415c0549d33cca6813441a2495976b66d4c00e
Reviewed-by: Lars Knoll <lars.knoll@digia.com>

3 files changed, 22 insertions, 24 deletions

diff --git a/src/qml/jit/qv4assembler.cpp b/src/qml/jit/qv4assembler.cpp
index afbdeeb10b..e0fe31d6cf 100644
--- a/src/qml/jit/qv4assembler.cpp
+++ b/src/qml/jit/qv4assembler.cpp
@@ -219,11 +219,8 @@ Assembler::Pointer Assembler::loadStringAddress(RegisterID reg, const QString &s
 
 void Assembler::loadStringRef(RegisterID reg, const QString &string)
 {
-    loadPtr(Address(Assembler::EngineRegister, qOffsetOf(QV4::ExecutionEngine, current)), reg);
-    loadPtr(Address(reg, qOffsetOf(QV4::Heap::ExecutionContext, compilationUnit)), reg);
-    loadPtr(Address(reg, qOffsetOf(QV4::CompiledData::CompilationUnit, runtimeStrings)), reg);
     const int id = _isel->registerString(string);
-    loadPtr(Address(reg, id * sizeof(QV4::String*)), reg);
+    move(TrustedImm32(id), reg);
 }
 
 void Assembler::storeValue(QV4::Primitive value, IR::Expr *destination)
diff --git a/src/qml/jit/qv4assembler_p.h b/src/qml/jit/qv4assembler_p.h
index a4105550c6..a143690793 100644
--- a/src/qml/jit/qv4assembler_p.h
+++ b/src/qml/jit/qv4assembler_p.h
@@ -316,8 +316,8 @@ public:
         {}
         IR::Expr *value;
     };
-    struct PointerToString {
-        explicit PointerToString(const QString &string) : string(string) {}
+    struct StringToIndex {
+        explicit StringToIndex(const QString &string) : string(string) {}
         QString string;
     };
     struct Reference {
@@ -446,7 +446,7 @@ public:
             loadArgumentInRegister(addr, dest, argumentNumber);
         }
     }
-    void loadArgumentInRegister(PointerToString temp, RegisterID dest, int argumentNumber)
+    void loadArgumentInRegister(StringToIndex temp, RegisterID dest, int argumentNumber)
     {
         Q_UNUSED(argumentNumber);
         loadStringRef(dest, temp.string);
@@ -662,7 +662,7 @@ public:
     }
 
     template <int StackSlot>
-    void loadArgumentOnStack(PointerToString temp, int argumentNumber)
+    void loadArgumentOnStack(StringToIndex temp, int argumentNumber)
     {
         Q_UNUSED(argumentNumber);
         loadStringRef(ScratchRegister, temp.string);
diff --git a/src/qml/jit/qv4isel_masm.cpp b/src/qml/jit/qv4isel_masm.cpp
index 5c441a1edf..ff35abda67 100644
--- a/src/qml/jit/qv4isel_masm.cpp
+++ b/src/qml/jit/qv4isel_masm.cpp
@@ -313,7 +313,7 @@ void InstructionSelection::callBuiltinInvalid(IR::Name *func, IR::ExprList *args
     } else {
         generateFunctionCall(result, Runtime::callActivationProperty,
                              Assembler::EngineRegister,
-                             Assembler::PointerToString(*func->id),
+                             Assembler::StringToIndex(*func->id),
                              baseAddressForCallData());
     }
 }
@@ -322,7 +322,7 @@ void InstructionSelection::callBuiltinTypeofMember(IR::Expr *base, const QString
                                                    IR::Expr *result)
 {
     generateFunctionCall(result, Runtime::typeofMember, Assembler::EngineRegister,
-                         Assembler::PointerToValue(base), Assembler::PointerToString(name));
+                         Assembler::PointerToValue(base), Assembler::StringToIndex(name));
 }
 
 void InstructionSelection::callBuiltinTypeofSubscript(IR::Expr *base, IR::Expr *index,
@@ -336,7 +336,7 @@ void InstructionSelection::callBuiltinTypeofSubscript(IR::Expr *base, IR::Expr *
 void InstructionSelection::callBuiltinTypeofName(const QString &name, IR::Expr *result)
 {
     generateFunctionCall(result, Runtime::typeofName, Assembler::EngineRegister,
-                         Assembler::PointerToString(name));
+                         Assembler::StringToIndex(name));
 }
 
 void InstructionSelection::callBuiltinTypeofValue(IR::Expr *value, IR::Expr *result)
@@ -348,7 +348,7 @@ void InstructionSelection::callBuiltinTypeofValue(IR::Expr *value, IR::Expr *res
 void InstructionSelection::callBuiltinDeleteMember(IR::Expr *base, const QString &name, IR::Expr *result)
 {
     generateFunctionCall(result, Runtime::deleteMember, Assembler::EngineRegister,
-                         Assembler::Reference(base), Assembler::PointerToString(name));
+                         Assembler::Reference(base), Assembler::StringToIndex(name));
 }
 
 void InstructionSelection::callBuiltinDeleteSubscript(IR::Expr *base, IR::Expr *index,
@@ -361,7 +361,7 @@ void InstructionSelection::callBuiltinDeleteSubscript(IR::Expr *base, IR::Expr *
 void InstructionSelection::callBuiltinDeleteName(const QString &name, IR::Expr *result)
 {
     generateFunctionCall(result, Runtime::deleteName, Assembler::EngineRegister,
-                         Assembler::PointerToString(name));
+                         Assembler::StringToIndex(name));
 }
 
 void InstructionSelection::callBuiltinDeleteValue(IR::Expr *result)
@@ -388,7 +388,7 @@ void InstructionSelection::callBuiltinUnwindException(IR::Expr *result)
 
 void InstructionSelection::callBuiltinPushCatchScope(const QString &exceptionName)
 {
-    generateFunctionCall(Assembler::Void, Runtime::pushCatchScope, Assembler::EngineRegister, Assembler::PointerToString(exceptionName));
+    generateFunctionCall(Assembler::Void, Runtime::pushCatchScope, Assembler::EngineRegister, Assembler::StringToIndex(exceptionName));
 }
 
 void InstructionSelection::callBuiltinForeachIteratorObject(IR::Expr *arg, IR::Expr *result)
@@ -422,7 +422,7 @@ void InstructionSelection::callBuiltinPopScope()
 void InstructionSelection::callBuiltinDeclareVar(bool deletable, const QString &name)
 {
     generateFunctionCall(Assembler::Void, Runtime::declareVar, Assembler::EngineRegister,
-                         Assembler::TrustedImm32(deletable), Assembler::PointerToString(name));
+                         Assembler::TrustedImm32(deletable), Assembler::StringToIndex(name));
 }
 
 void InstructionSelection::callBuiltinDefineArray(IR::Expr *result, IR::ExprList *args)
@@ -575,7 +575,7 @@ void InstructionSelection::loadQmlScopeObject(IR::Expr *temp)
 
 void InstructionSelection::loadQmlSingleton(const QString &name, IR::Expr *temp)
 {
-    generateFunctionCall(temp, Runtime::getQmlSingleton, Assembler::EngineRegister, Assembler::PointerToString(name));
+    generateFunctionCall(temp, Runtime::getQmlSingleton, Assembler::EngineRegister, Assembler::StringToIndex(name));
 }
 
 void InstructionSelection::loadConst(IR::Const *sourceConst, IR::Expr *target)
@@ -632,14 +632,14 @@ void InstructionSelection::getActivationProperty(const IR::Name *name, IR::Expr
         generateLookupCall(target, index, qOffsetOf(QV4::Lookup, globalGetter), Assembler::EngineRegister, Assembler::Void);
         return;
     }
-    generateFunctionCall(target, Runtime::getActivationProperty, Assembler::EngineRegister, Assembler::PointerToString(*name->id));
+    generateFunctionCall(target, Runtime::getActivationProperty, Assembler::EngineRegister, Assembler::StringToIndex(*name->id));
 }
 
 void InstructionSelection::setActivationProperty(IR::Expr *source, const QString &targetName)
 {
     // ### should use a lookup call here
     generateFunctionCall(Assembler::Void, Runtime::setActivationProperty,
-                         Assembler::EngineRegister, Assembler::PointerToString(targetName), Assembler::PointerToValue(source));
+                         Assembler::EngineRegister, Assembler::StringToIndex(targetName), Assembler::PointerToValue(source));
 }
 
 void InstructionSelection::initClosure(IR::Closure *closure, IR::Expr *target)
@@ -652,10 +652,10 @@ void InstructionSelection::getProperty(IR::Expr *base, const QString &name, IR::
 {
     if (useFastLookups) {
         uint index = registerGetterLookup(name);
-        generateLookupCall(target, index, qOffsetOf(QV4::Lookup, getter), Assembler::PointerToValue(base), Assembler::Void);
+        generateLookupCall(target, index, qOffsetOf(QV4::Lookup, getter), Assembler::EngineRegister, Assembler::PointerToValue(base), Assembler::Void);
     } else {
         generateFunctionCall(target, Runtime::getProperty, Assembler::EngineRegister,
-                             Assembler::PointerToValue(base), Assembler::PointerToString(name));
+                             Assembler::PointerToValue(base), Assembler::StringToIndex(name));
     }
 }
 
@@ -677,11 +677,12 @@ void InstructionSelection::setProperty(IR::Expr *source, IR::Expr *targetBase,
     if (useFastLookups) {
         uint index = registerSetterLookup(targetName);
         generateLookupCall(Assembler::Void, index, qOffsetOf(QV4::Lookup, setter),
+                           Assembler::EngineRegister,
                            Assembler::PointerToValue(targetBase),
                            Assembler::PointerToValue(source));
     } else {
         generateFunctionCall(Assembler::Void, Runtime::setProperty, Assembler::EngineRegister,
-                             Assembler::PointerToValue(targetBase), Assembler::PointerToString(targetName),
+                             Assembler::PointerToValue(targetBase), Assembler::StringToIndex(targetName),
                              Assembler::PointerToValue(source));
     }
 }
@@ -894,7 +895,7 @@ void InstructionSelection::callProperty(IR::Expr *base, const QString &name, IR:
                              baseAddressForCallData());
     } else {
         generateFunctionCall(result, Runtime::callProperty, Assembler::EngineRegister,
-                             Assembler::PointerToString(name),
+                             Assembler::StringToIndex(name),
                              baseAddressForCallData());
     }
 }
@@ -1222,7 +1223,7 @@ void InstructionSelection::constructActivationProperty(IR::Name *func, IR::ExprL
 
     generateFunctionCall(result, Runtime::constructActivationProperty,
                          Assembler::EngineRegister,
-                         Assembler::PointerToString(*func->id),
+                         Assembler::StringToIndex(*func->id),
                          baseAddressForCallData());
 }
 
@@ -1240,7 +1241,7 @@ void InstructionSelection::constructProperty(IR::Expr *base, const QString &name
     }
 
     generateFunctionCall(result, Runtime::constructProperty, Assembler::EngineRegister,
-                         Assembler::PointerToString(name),
+                         Assembler::StringToIndex(name),
                          baseAddressForCallData());
 }