webkitgtk-2.4.9webkitgtk-2.4.9

1 files changed, 144 insertions, 184 deletions

diff --git a/Source/JavaScriptCore/runtime/Executable.h b/Source/JavaScriptCore/runtime/Executable.h
index bce2428cb..6ff27aee9 100644
--- a/Source/JavaScriptCore/runtime/Executable.h
+++ b/Source/JavaScriptCore/runtime/Executable.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009, 2010, 2013-2015 Apple Inc. All rights reserved.
+ * Copyright (C) 2009, 2010, 2013 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -26,23 +26,20 @@
 #ifndef Executable_h
 #define Executable_h
 
-#include "ArityCheckMode.h"
 #include "CallData.h"
 #include "CodeBlockHash.h"
 #include "CodeSpecializationKind.h"
 #include "CompilationResult.h"
 #include "DFGPlan.h"
-#include "ExecutableInfo.h"
 #include "HandlerInfo.h"
-#include "InferredValue.h"
+#include "JSFunction.h"
+#include "Interpreter.h"
 #include "JITCode.h"
 #include "JSGlobalObject.h"
-#include "RegisterPreservationMode.h"
 #include "SamplingTool.h"
 #include "SourceCode.h"
-#include "TypeSet.h"
 #include "UnlinkedCodeBlock.h"
-#include "UnlinkedFunctionExecutable.h"
+#include <wtf/PassOwnPtr.h>
 
 namespace JSC {
 
@@ -64,7 +61,8 @@ inline bool isCall(CodeSpecializationKind kind)
     return false;
 }
 
-class ExecutableBase : public JSCell {
+class ExecutableBase : public JSCell, public DoublyLinkedListNode<ExecutableBase> {
+    friend class WTF::DoublyLinkedListNode<ExecutableBase>;
     friend class JIT;
 
 protected:
@@ -85,24 +83,26 @@ protected:
 
 public:
     typedef JSCell Base;
-    static const unsigned StructureFlags = Base::StructureFlags;
 
+#if ENABLE(JIT)
     static const bool needsDestruction = true;
+    static const bool hasImmortalStructure = true;
     static void destroy(JSCell*);
+#endif
         
     CodeBlockHash hashFor(CodeSpecializationKind) const;
 
     bool isEvalExecutable()
     {
-        return type() == EvalExecutableType;
+        return structure()->typeInfo().type() == EvalExecutableType;
     }
     bool isFunctionExecutable()
     {
-        return type() == FunctionExecutableType;
+        return structure()->typeInfo().type() == FunctionExecutableType;
     }
     bool isProgramExecutable()
     {
-        return type() == ProgramExecutableType;
+        return structure()->typeInfo().type() == ProgramExecutableType;
     }
 
     bool isHostFunction() const
@@ -111,13 +111,14 @@ public:
         return m_numParametersForCall == NUM_PARAMETERS_IS_HOST;
     }
 
-    static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue proto) { return Structure::create(vm, globalObject, proto, TypeInfo(CellType, StructureFlags), info()); }
+    static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue proto) { return Structure::create(vm, globalObject, proto, TypeInfo(CompoundType, StructureFlags), info()); }
         
     void clearCode();
 
     DECLARE_EXPORT_INFO;
 
 protected:
+    static const unsigned StructureFlags = 0;
     int m_numParametersForCall;
     int m_numParametersForConstruct;
 
@@ -143,94 +144,37 @@ public:
         ASSERT(kind == CodeForConstruct);
         return generatedJITCodeForConstruct();
     }
-    
-    MacroAssemblerCodePtr entrypointFor(
-        VM& vm, CodeSpecializationKind kind, ArityCheckMode arity, RegisterPreservationMode registers)
-    {
-        // Check if we have a cached result. We only have it for arity check because we use the
-        // no-arity entrypoint in non-virtual calls, which will "cache" this value directly in
-        // machine code.
-        if (arity == MustCheckArity) {
-            switch (kind) {
-            case CodeForCall:
-                switch (registers) {
-                case RegisterPreservationNotRequired:
-                    if (MacroAssemblerCodePtr result = m_jitCodeForCallWithArityCheck)
-                        return result;
-                    break;
-                case MustPreserveRegisters:
-                    if (MacroAssemblerCodePtr result = m_jitCodeForCallWithArityCheckAndPreserveRegs)
-                        return result;
-                    break;
-                }
-                break;
-            case CodeForConstruct:
-                switch (registers) {
-                case RegisterPreservationNotRequired:
-                    if (MacroAssemblerCodePtr result = m_jitCodeForConstructWithArityCheck)
-                        return result;
-                    break;
-                case MustPreserveRegisters:
-                    if (MacroAssemblerCodePtr result = m_jitCodeForConstructWithArityCheckAndPreserveRegs)
-                        return result;
-                    break;
-                }
-                break;
-            }
-        }
-        MacroAssemblerCodePtr result =
-            generatedJITCodeFor(kind)->addressForCall(vm, this, arity, registers);
-        if (arity == MustCheckArity) {
-            // Cache the result; this is necessary for the JIT's virtual call optimizations.
-            switch (kind) {
-            case CodeForCall:
-                switch (registers) {
-                case RegisterPreservationNotRequired:
-                    m_jitCodeForCallWithArityCheck = result;
-                    break;
-                case MustPreserveRegisters:
-                    m_jitCodeForCallWithArityCheckAndPreserveRegs = result;
-                    break;
-                }
-                break;
-            case CodeForConstruct:
-                switch (registers) {
-                case RegisterPreservationNotRequired:
-                    m_jitCodeForConstructWithArityCheck = result;
-                    break;
-                case MustPreserveRegisters:
-                    m_jitCodeForConstructWithArityCheckAndPreserveRegs = result;
-                    break;
-                }
-                break;
-            }
-        }
-        return result;
-    }
-
-    static ptrdiff_t offsetOfJITCodeWithArityCheckFor(
-        CodeSpecializationKind kind, RegisterPreservationMode registers)
-    {
-        switch (kind) {
-        case CodeForCall:
-            switch (registers) {
-            case RegisterPreservationNotRequired:
-                return OBJECT_OFFSETOF(ExecutableBase, m_jitCodeForCallWithArityCheck);
-            case MustPreserveRegisters:
-                return OBJECT_OFFSETOF(ExecutableBase, m_jitCodeForCallWithArityCheckAndPreserveRegs);
-            }
-        case CodeForConstruct:
-            switch (registers) {
-            case RegisterPreservationNotRequired:
-                return OBJECT_OFFSETOF(ExecutableBase, m_jitCodeForConstructWithArityCheck);
-            case MustPreserveRegisters:
-                return OBJECT_OFFSETOF(ExecutableBase, m_jitCodeForConstructWithArityCheckAndPreserveRegs);
-            }
-        }
-        RELEASE_ASSERT_NOT_REACHED();
-        return 0;
+
+    MacroAssemblerCodePtr generatedJITCodeForCallWithArityCheck()
+    {
+        ASSERT(m_jitCodeForCall);
+        ASSERT(m_jitCodeForCallWithArityCheck);
+        return m_jitCodeForCallWithArityCheck;
     }
-    
+
+    MacroAssemblerCodePtr generatedJITCodeForConstructWithArityCheck()
+    {
+        ASSERT(m_jitCodeForConstruct);
+        ASSERT(m_jitCodeForConstructWithArityCheck);
+        return m_jitCodeForConstructWithArityCheck;
+    }
+        
+    MacroAssemblerCodePtr generatedJITCodeWithArityCheckFor(CodeSpecializationKind kind)
+    {
+        if (kind == CodeForCall)
+            return generatedJITCodeForCallWithArityCheck();
+        ASSERT(kind == CodeForConstruct);
+        return generatedJITCodeForConstructWithArityCheck();
+    }
+        
+    static ptrdiff_t offsetOfJITCodeWithArityCheckFor(CodeSpecializationKind kind)
+    {
+        if (kind == CodeForCall)
+            return OBJECT_OFFSETOF(ExecutableBase, m_jitCodeForCallWithArityCheck);
+        ASSERT(kind == CodeForConstruct);
+        return OBJECT_OFFSETOF(ExecutableBase, m_jitCodeForConstructWithArityCheck);
+    }
+        
     static ptrdiff_t offsetOfNumParametersFor(CodeSpecializationKind kind)
     {
         if (kind == CodeForCall)
@@ -266,34 +210,52 @@ public:
             return intrinsic();
         return NoIntrinsic;
     }
-    
-    void dump(PrintStream&) const;
         
+    MacroAssemblerCodePtr hostCodeEntryFor(CodeSpecializationKind kind)
+    {
+        return generatedJITCodeFor(kind)->addressForCall();
+    }
+
+    MacroAssemblerCodePtr jsCodeEntryFor(CodeSpecializationKind kind)
+    {
+        return generatedJITCodeFor(kind)->addressForCall();
+    }
+
+    MacroAssemblerCodePtr jsCodeWithArityCheckEntryFor(CodeSpecializationKind kind)
+    {
+        return generatedJITCodeWithArityCheckFor(kind);
+    }
+
 protected:
+    ExecutableBase* m_prev;
+    ExecutableBase* m_next;
+
     RefPtr<JITCode> m_jitCodeForCall;
     RefPtr<JITCode> m_jitCodeForConstruct;
     MacroAssemblerCodePtr m_jitCodeForCallWithArityCheck;
     MacroAssemblerCodePtr m_jitCodeForConstructWithArityCheck;
-    MacroAssemblerCodePtr m_jitCodeForCallWithArityCheckAndPreserveRegs;
-    MacroAssemblerCodePtr m_jitCodeForConstructWithArityCheckAndPreserveRegs;
 };
 
-class NativeExecutable final : public ExecutableBase {
+class NativeExecutable : public ExecutableBase {
     friend class JIT;
     friend class LLIntOffsetsExtractor;
 public:
     typedef ExecutableBase Base;
-    static const unsigned StructureFlags = Base::StructureFlags | StructureIsImmortal;
 
-    static NativeExecutable* create(VM& vm, PassRefPtr<JITCode> callThunk, NativeFunction function, PassRefPtr<JITCode> constructThunk, NativeFunction constructor, Intrinsic intrinsic)
+    static NativeExecutable* create(VM& vm, MacroAssemblerCodeRef callThunk, NativeFunction function, MacroAssemblerCodeRef constructThunk, NativeFunction constructor, Intrinsic intrinsic)
     {
         NativeExecutable* executable;
         executable = new (NotNull, allocateCell<NativeExecutable>(vm.heap)) NativeExecutable(vm, function, constructor);
-        executable->finishCreation(vm, callThunk, constructThunk, intrinsic);
+        if (!callThunk)
+            executable->finishCreation(vm, 0, 0, intrinsic);
+        else
+            executable->finishCreation(vm, JITCode::hostFunction(callThunk), JITCode::hostFunction(constructThunk), intrinsic);
         return executable;
     }
 
+#if ENABLE(JIT)
     static void destroy(JSCell*);
+#endif
 
     CodeBlockHash hashFor(CodeSpecializationKind) const;
 
@@ -316,7 +278,7 @@ public:
         return OBJECT_OFFSETOF(NativeExecutable, m_constructor);
     }
 
-    static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue proto) { return Structure::create(vm, globalObject, proto, TypeInfo(CellType, StructureFlags), info()); }
+    static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue proto) { return Structure::create(vm, globalObject, proto, TypeInfo(LeafType, StructureFlags), info()); }
         
     DECLARE_INFO;
 
@@ -326,6 +288,8 @@ protected:
     void finishCreation(VM& vm, PassRefPtr<JITCode> callThunk, PassRefPtr<JITCode> constructThunk, Intrinsic intrinsic)
     {
         Base::finishCreation(vm);
+        m_jitCodeForCallWithArityCheck = callThunk ? callThunk->addressForCall() : MacroAssemblerCodePtr();
+        m_jitCodeForConstructWithArityCheck = constructThunk ? constructThunk->addressForCall() : MacroAssemblerCodePtr();
         m_jitCodeForCall = callThunk;
         m_jitCodeForConstruct = constructThunk;
         m_intrinsic = intrinsic;
@@ -348,24 +312,40 @@ private:
 class ScriptExecutable : public ExecutableBase {
 public:
     typedef ExecutableBase Base;
-    static const unsigned StructureFlags = Base::StructureFlags;
 
+    ScriptExecutable(Structure* structure, VM& vm, const SourceCode& source, bool isInStrictContext)
+        : ExecutableBase(vm, structure, NUM_PARAMETERS_NOT_COMPILED)
+        , m_source(source)
+        , m_features(isInStrictContext ? StrictModeFeature : 0)
+        , m_neverInline(false)
+        , m_startColumn(UINT_MAX)
+        , m_endColumn(UINT_MAX)
+    {
+    }
+
+    ScriptExecutable(Structure* structure, ExecState* exec, const SourceCode& source, bool isInStrictContext)
+        : ExecutableBase(exec->vm(), structure, NUM_PARAMETERS_NOT_COMPILED)
+        , m_source(source)
+        , m_features(isInStrictContext ? StrictModeFeature : 0)
+        , m_neverInline(false)
+        , m_startColumn(UINT_MAX)
+        , m_endColumn(UINT_MAX)
+    {
+    }
+
+#if ENABLE(JIT)
     static void destroy(JSCell*);
+#endif
         
     CodeBlockHash hashFor(CodeSpecializationKind) const;
 
     const SourceCode& source() const { return m_source; }
     intptr_t sourceID() const { return m_source.providerID(); }
     const String& sourceURL() const { return m_source.provider()->url(); }
-    int firstLine() const { return m_firstLine; }
-    void setOverrideLineNumber(int overrideLineNumber) { m_overrideLineNumber = overrideLineNumber; }
-    bool hasOverrideLineNumber() const { return m_overrideLineNumber != -1; }
-    int overrideLineNumber() const { return m_overrideLineNumber; }
+    int lineNo() const { return m_firstLine; }
     int lastLine() const { return m_lastLine; }
     unsigned startColumn() const { return m_startColumn; }
     unsigned endColumn() const { return m_endColumn; }
-    unsigned typeProfilingStartOffset() const { return m_typeProfilingStartOffset; }
-    unsigned typeProfilingEndOffset() const { return m_typeProfilingEndOffset; }
 
     bool usesEval() const { return m_features & EvalFeature; }
     bool usesArguments() const { return m_features & ArgumentsFeature; }
@@ -374,12 +354,8 @@ public:
     ECMAMode ecmaMode() const { return isStrictMode() ? StrictMode : NotStrictMode; }
         
     void setNeverInline(bool value) { m_neverInline = value; }
-    void setDidTryToEnterInLoop(bool value) { m_didTryToEnterInLoop = value; }
     bool neverInline() const { return m_neverInline; }
-    bool didTryToEnterInLoop() const { return m_didTryToEnterInLoop; }
     bool isInliningCandidate() const { return !neverInline(); }
-    
-    bool* addressOfDidTryToEnterInLoop() { return &m_didTryToEnterInLoop; }
 
     void unlinkCalls();
         
@@ -400,24 +376,20 @@ public:
     }
 
     void installCode(CodeBlock*);
-    RefPtr<CodeBlock> newCodeBlockFor(CodeSpecializationKind, JSFunction*, JSScope*, JSObject*& exception);
+    PassRefPtr<CodeBlock> newCodeBlockFor(CodeSpecializationKind, JSScope*, JSObject*& exception);
     PassRefPtr<CodeBlock> newReplacementCodeBlockFor(CodeSpecializationKind);
     
-    JSObject* prepareForExecution(ExecState* exec, JSFunction* function, JSScope* scope, CodeSpecializationKind kind)
+    JSObject* prepareForExecution(ExecState* exec, JSScope* scope, CodeSpecializationKind kind)
     {
         if (hasJITCodeFor(kind))
             return 0;
-        return prepareForExecutionImpl(exec, function, scope, kind);
+        return prepareForExecutionImpl(exec, scope, kind);
     }
 
-    template <typename Functor> void forEachCodeBlock(Functor&&);
-
 private:
-    JSObject* prepareForExecutionImpl(ExecState*, JSFunction*, JSScope*, CodeSpecializationKind);
+    JSObject* prepareForExecutionImpl(ExecState*, JSScope*, CodeSpecializationKind);
 
 protected:
-    ScriptExecutable(Structure* structure, VM& vm, const SourceCode& source, bool isInStrictContext);
-
     void finishCreation(VM& vm)
     {
         Base::finishCreation(vm);
@@ -433,21 +405,16 @@ protected:
     CodeFeatures m_features;
     bool m_hasCapturedVariables;
     bool m_neverInline;
-    bool m_didTryToEnterInLoop;
-    int m_overrideLineNumber;
     int m_firstLine;
     int m_lastLine;
     unsigned m_startColumn;
     unsigned m_endColumn;
-    unsigned m_typeProfilingStartOffset;
-    unsigned m_typeProfilingEndOffset;
 };
 
-class EvalExecutable final : public ScriptExecutable {
+class EvalExecutable : public ScriptExecutable {
     friend class LLIntOffsetsExtractor;
 public:
     typedef ScriptExecutable Base;
-    static const unsigned StructureFlags = Base::StructureFlags | StructureIsImmortal;
 
     static void destroy(JSCell*);
 
@@ -456,7 +423,7 @@ public:
         return m_evalCodeBlock.get();
     }
 
-    static EvalExecutable* create(ExecState*, const SourceCode&, bool isInStrictContext, ThisTDZMode, const VariableEnvironment*);
+    static EvalExecutable* create(ExecState*, const SourceCode&, bool isInStrictContext);
 
     PassRefPtr<JITCode> generatedJITCode()
     {
@@ -474,13 +441,14 @@ public:
 
     void clearCode();
 
-    ExecutableInfo executableInfo() const { return ExecutableInfo(needsActivation(), usesEval(), isStrictMode(), false, false, ConstructorKind::None); }
+    ExecutableInfo executableInfo() const { return ExecutableInfo(needsActivation(), usesEval(), isStrictMode(), false); }
 
     unsigned numVariables() { return m_unlinkedEvalCodeBlock->numVariables(); }
     unsigned numberOfFunctionDecls() { return m_unlinkedEvalCodeBlock->numberOfFunctionDecls(); }
 
 private:
     friend class ScriptExecutable;
+    static const unsigned StructureFlags = OverridesVisitChildren | ScriptExecutable::StructureFlags;
     EvalExecutable(ExecState*, const SourceCode&, bool);
 
     static void visitChildren(JSCell*, SlotVisitor&);
@@ -489,11 +457,10 @@ private:
     WriteBarrier<UnlinkedEvalCodeBlock> m_unlinkedEvalCodeBlock;
 };
 
-class ProgramExecutable final : public ScriptExecutable {
+class ProgramExecutable : public ScriptExecutable {
     friend class LLIntOffsetsExtractor;
 public:
     typedef ScriptExecutable Base;
-    static const unsigned StructureFlags = Base::StructureFlags | StructureIsImmortal;
 
     static ProgramExecutable* create(ExecState* exec, const SourceCode& source)
     {
@@ -530,10 +497,12 @@ public:
 
     void clearCode();
 
-    ExecutableInfo executableInfo() const { return ExecutableInfo(needsActivation(), usesEval(), isStrictMode(), false, false, ConstructorKind::None); }
+    ExecutableInfo executableInfo() const { return ExecutableInfo(needsActivation(), usesEval(), isStrictMode(), false); }
 
 private:
     friend class ScriptExecutable;
+    
+    static const unsigned StructureFlags = OverridesVisitChildren | ScriptExecutable::StructureFlags;
 
     ProgramExecutable(ExecState*, const SourceCode&);
 
@@ -543,24 +512,19 @@ private:
     RefPtr<ProgramCodeBlock> m_programCodeBlock;
 };
 
-class FunctionExecutable final : public ScriptExecutable {
+class FunctionExecutable : public ScriptExecutable {
     friend class JIT;
     friend class LLIntOffsetsExtractor;
 public:
     typedef ScriptExecutable Base;
-    static const unsigned StructureFlags = Base::StructureFlags | StructureIsImmortal;
 
-    static FunctionExecutable* create(
-        VM& vm, const SourceCode& source, UnlinkedFunctionExecutable* unlinkedExecutable, 
-        unsigned firstLine, unsigned lastLine, unsigned startColumn, unsigned endColumn)
+    static FunctionExecutable* create(VM& vm, const SourceCode& source, UnlinkedFunctionExecutable* unlinkedExecutable, unsigned firstLine, unsigned lastLine, unsigned startColumn, unsigned endColumn, bool bodyIncludesBraces = true)
     {
-        FunctionExecutable* executable = new (NotNull, allocateCell<FunctionExecutable>(vm.heap)) FunctionExecutable(vm, source, unlinkedExecutable, firstLine, lastLine, startColumn, endColumn);
+        FunctionExecutable* executable = new (NotNull, allocateCell<FunctionExecutable>(vm.heap)) FunctionExecutable(vm, source, unlinkedExecutable, firstLine, lastLine, startColumn, endColumn, bodyIncludesBraces);
         executable->finishCreation(vm);
         return executable;
     }
-    static FunctionExecutable* fromGlobalCode(
-        const Identifier& name, ExecState&, const SourceCode&, 
-        JSObject*& exception, int overrideLineNumber);
+    static FunctionExecutable* fromGlobalCode(const Identifier& name, ExecState*, Debugger*, const SourceCode&, JSObject** exception);
 
     static void destroy(JSCell*);
         
@@ -621,68 +585,64 @@ public:
     {
         return baselineCodeBlockFor(kind);
     }
-
-    RefPtr<TypeSet> returnStatementTypeSet() 
-    {
-        if (!m_returnStatementTypeSet)
-            m_returnStatementTypeSet = TypeSet::create();
-
-        return m_returnStatementTypeSet;
-    }
         
-    FunctionMode functionMode() { return m_unlinkedExecutable->functionMode(); }
-    bool isBuiltinFunction() const { return m_unlinkedExecutable->isBuiltinFunction(); }
-    ConstructAbility constructAbility() const { return m_unlinkedExecutable->constructAbility(); }
-    bool isClassConstructorFunction() const { return m_unlinkedExecutable->isClassConstructorFunction(); }
     const Identifier& name() { return m_unlinkedExecutable->name(); }
     const Identifier& inferredName() { return m_unlinkedExecutable->inferredName(); }
     JSString* nameValue() const { return m_unlinkedExecutable->nameValue(); }
     size_t parameterCount() const { return m_unlinkedExecutable->parameterCount(); } // Excluding 'this'!
+    String paramString() const;
+    SymbolTable* symbolTable(CodeSpecializationKind);
 
-    void clearUnlinkedCodeForRecompilation();
+    void clearCodeIfNotCompiling();
+    void clearUnlinkedCodeForRecompilationIfNotCompiling();
     static void visitChildren(JSCell*, SlotVisitor&);
     static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue proto)
     {
         return Structure::create(vm, globalObject, proto, TypeInfo(FunctionExecutableType, StructureFlags), info());
     }
-
-    unsigned parametersStartOffset() const { return m_parametersStartOffset; }
-
-    void overrideParameterAndTypeProfilingStartEndOffsets(unsigned parametersStartOffset, unsigned typeProfilingStartOffset, unsigned typeProfilingEndOffset)
-    {
-        m_parametersStartOffset = parametersStartOffset;
-        m_typeProfilingStartOffset = typeProfilingStartOffset;
-        m_typeProfilingEndOffset = typeProfilingEndOffset;
-    }
-
+        
     DECLARE_INFO;
         
     void unlinkCalls();
 
     void clearCode();
-    
-    InferredValue* singletonFunction() { return m_singletonFunction.get(); }
+
+    bool bodyIncludesBraces() const { return m_bodyIncludesBraces; }
 
 private:
-    FunctionExecutable(
-        VM&, const SourceCode&, UnlinkedFunctionExecutable*, unsigned firstLine, 
-        unsigned lastLine, unsigned startColumn, unsigned endColumn);
-    
-    void finishCreation(VM&);
+    FunctionExecutable(VM&, const SourceCode&, UnlinkedFunctionExecutable*, unsigned firstLine, unsigned lastLine, unsigned startColumn, unsigned endColumn, bool bodyIncludesBraces);
+
+    bool isCompiling()
+    {
+#if ENABLE(JIT)
+        if (!m_jitCodeForCall && m_codeBlockForCall)
+            return true;
+        if (!m_jitCodeForConstruct && m_codeBlockForConstruct)
+            return true;
+#endif
+        return false;
+    }
 
     friend class ScriptExecutable;
-    
+
+    static const unsigned StructureFlags = OverridesVisitChildren | ScriptExecutable::StructureFlags;
     WriteBarrier<UnlinkedFunctionExecutable> m_unlinkedExecutable;
     RefPtr<FunctionCodeBlock> m_codeBlockForCall;
     RefPtr<FunctionCodeBlock> m_codeBlockForConstruct;
-    RefPtr<TypeSet> m_returnStatementTypeSet;
-    unsigned m_parametersStartOffset;
-    WriteBarrier<InferredValue> m_singletonFunction;
+    bool m_bodyIncludesBraces;
 };
 
+inline bool isHostFunction(JSValue value, NativeFunction nativeFunction)
+{
+    JSFunction* function = jsCast<JSFunction*>(getJSFunction(value));
+    if (!function || !function->isHostFunction())
+        return false;
+    return function->nativeFunction() == nativeFunction;
+}
+
 inline void ExecutableBase::clearCodeVirtual(ExecutableBase* executable)
 {
-    switch (executable->type()) {
+    switch (executable->structure()->typeInfo().type()) {
     case EvalExecutableType:
         return jsCast<EvalExecutable*>(executable)->clearCode();
     case ProgramExecutableType:
@@ -696,7 +656,7 @@ inline void ExecutableBase::clearCodeVirtual(ExecutableBase* executable)
 
 inline void ScriptExecutable::unlinkCalls()
 {
-    switch (type()) {
+    switch (structure()->typeInfo().type()) {
     case EvalExecutableType:
         return jsCast<EvalExecutable*>(this)->unlinkCalls();
     case ProgramExecutableType: