Imported WebKit commit 2ea9d364d0f6efa8fa64acf19f451504c59be0e4 (http://svn.webkit.org/repository/webkit/trunk@104285)

1 files changed, 1175 insertions, 0 deletions

diff --git a/Source/JavaScriptCore/jit/JIT.h b/Source/JavaScriptCore/jit/JIT.h
new file mode 100644
index 000000000..750b9d818
--- /dev/null
+++ b/Source/JavaScriptCore/jit/JIT.h
@@ -0,0 +1,1175 @@
+/*
+ * Copyright (C) 2008 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``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 APPLE INC. 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. 
+ */
+
+#ifndef JIT_h
+#define JIT_h
+
+#if ENABLE(JIT)
+
+// Verbose logging of code generation
+#define ENABLE_JIT_VERBOSE 0
+// Verbose logging for OSR-related code.
+#define ENABLE_JIT_VERBOSE_OSR 0
+
+// We've run into some problems where changing the size of the class JIT leads to
+// performance fluctuations.  Try forcing alignment in an attempt to stabalize this.
+#if COMPILER(GCC)
+#define JIT_CLASS_ALIGNMENT __attribute__ ((aligned (32)))
+#else
+#define JIT_CLASS_ALIGNMENT
+#endif
+
+#define ASSERT_JIT_OFFSET_UNUSED(variable, actual, expected) ASSERT_WITH_MESSAGE_UNUSED(variable, actual == expected, "JIT Offset \"%s\" should be %d, not %d.\n", #expected, static_cast<int>(expected), static_cast<int>(actual));
+#define ASSERT_JIT_OFFSET(actual, expected) ASSERT_WITH_MESSAGE(actual == expected, "JIT Offset \"%s\" should be %d, not %d.\n", #expected, static_cast<int>(expected), static_cast<int>(actual));
+
+#include "CodeBlock.h"
+#include "CompactJITCodeMap.h"
+#include "Interpreter.h"
+#include "JSInterfaceJIT.h"
+#include "Opcode.h"
+#include "Profiler.h"
+#include <bytecode/SamplingTool.h>
+
+namespace JSC {
+
+    class CodeBlock;
+    class FunctionExecutable;
+    class JIT;
+    class JSPropertyNameIterator;
+    class Interpreter;
+    class Register;
+    class RegisterFile;
+    class ScopeChainNode;
+    class StructureChain;
+
+    struct CallLinkInfo;
+    struct Instruction;
+    struct OperandTypes;
+    struct PolymorphicAccessStructureList;
+    struct SimpleJumpTable;
+    struct StringJumpTable;
+    struct StructureStubInfo;
+
+    struct CallRecord {
+        MacroAssembler::Call from;
+        unsigned bytecodeOffset;
+        void* to;
+
+        CallRecord()
+        {
+        }
+
+        CallRecord(MacroAssembler::Call from, unsigned bytecodeOffset, void* to = 0)
+            : from(from)
+            , bytecodeOffset(bytecodeOffset)
+            , to(to)
+        {
+        }
+    };
+
+    struct JumpTable {
+        MacroAssembler::Jump from;
+        unsigned toBytecodeOffset;
+
+        JumpTable(MacroAssembler::Jump f, unsigned t)
+            : from(f)
+            , toBytecodeOffset(t)
+        {
+        }
+    };
+
+    struct SlowCaseEntry {
+        MacroAssembler::Jump from;
+        unsigned to;
+        unsigned hint;
+        
+        SlowCaseEntry(MacroAssembler::Jump f, unsigned t, unsigned h = 0)
+            : from(f)
+            , to(t)
+            , hint(h)
+        {
+        }
+    };
+
+    struct SwitchRecord {
+        enum Type {
+            Immediate,
+            Character,
+            String
+        };
+
+        Type type;
+
+        union {
+            SimpleJumpTable* simpleJumpTable;
+            StringJumpTable* stringJumpTable;
+        } jumpTable;
+
+        unsigned bytecodeOffset;
+        unsigned defaultOffset;
+
+        SwitchRecord(SimpleJumpTable* jumpTable, unsigned bytecodeOffset, unsigned defaultOffset, Type type)
+            : type(type)
+            , bytecodeOffset(bytecodeOffset)
+            , defaultOffset(defaultOffset)
+        {
+            this->jumpTable.simpleJumpTable = jumpTable;
+        }
+
+        SwitchRecord(StringJumpTable* jumpTable, unsigned bytecodeOffset, unsigned defaultOffset)
+            : type(String)
+            , bytecodeOffset(bytecodeOffset)
+            , defaultOffset(defaultOffset)
+        {
+            this->jumpTable.stringJumpTable = jumpTable;
+        }
+    };
+
+    struct PropertyStubCompilationInfo {
+        unsigned bytecodeIndex;
+        MacroAssembler::Call callReturnLocation;
+        MacroAssembler::Label hotPathBegin;
+        
+#if !ASSERT_DISABLED
+        PropertyStubCompilationInfo()
+            : bytecodeIndex(std::numeric_limits<unsigned>::max())
+        {
+        }
+#endif
+    };
+
+    struct StructureStubCompilationInfo {
+        MacroAssembler::DataLabelPtr hotPathBegin;
+        MacroAssembler::Call hotPathOther;
+        MacroAssembler::Call callReturnLocation;
+        CallLinkInfo::CallType callType;
+        unsigned bytecodeIndex;
+    };
+
+    struct MethodCallCompilationInfo {
+        MethodCallCompilationInfo(unsigned bytecodeIndex, unsigned propertyAccessIndex)
+            : bytecodeIndex(bytecodeIndex)
+            , propertyAccessIndex(propertyAccessIndex)
+        {
+        }
+
+        unsigned bytecodeIndex;
+        MacroAssembler::DataLabelPtr structureToCompare;
+        unsigned propertyAccessIndex;
+    };
+
+    // Near calls can only be patched to other JIT code, regular calls can be patched to JIT code or relinked to stub functions.
+    void ctiPatchNearCallByReturnAddress(CodeBlock* codeblock, ReturnAddressPtr returnAddress, MacroAssemblerCodePtr newCalleeFunction);
+    void ctiPatchCallByReturnAddress(CodeBlock* codeblock, ReturnAddressPtr returnAddress, MacroAssemblerCodePtr newCalleeFunction);
+    void ctiPatchCallByReturnAddress(CodeBlock* codeblock, ReturnAddressPtr returnAddress, FunctionPtr newCalleeFunction);
+
+    class JIT : private JSInterfaceJIT {
+        friend class JITStubCall;
+
+        using MacroAssembler::Jump;
+        using MacroAssembler::JumpList;
+        using MacroAssembler::Label;
+
+        static const int patchGetByIdDefaultStructure = -1;
+        static const int patchGetByIdDefaultOffset = 0;
+        // Magic number - initial offset cannot be representable as a signed 8bit value, or the X86Assembler
+        // will compress the displacement, and we may not be able to fit a patched offset.
+        static const int patchPutByIdDefaultOffset = 256;
+
+    public:
+        static JITCode compile(JSGlobalData* globalData, CodeBlock* codeBlock, CodePtr* functionEntryArityCheck = 0)
+        {
+            return JIT(globalData, codeBlock).privateCompile(functionEntryArityCheck);
+        }
+
+        static void compileGetByIdProto(JSGlobalData* globalData, CallFrame* callFrame, CodeBlock* codeBlock, StructureStubInfo* stubInfo, Structure* structure, Structure* prototypeStructure, const Identifier& ident, const PropertySlot& slot, size_t cachedOffset, ReturnAddressPtr returnAddress)
+        {
+            JIT jit(globalData, codeBlock);
+            jit.privateCompileGetByIdProto(stubInfo, structure, prototypeStructure, ident, slot, cachedOffset, returnAddress, callFrame);
+        }
+
+        static void compileGetByIdSelfList(JSGlobalData* globalData, CodeBlock* codeBlock, StructureStubInfo* stubInfo, PolymorphicAccessStructureList* polymorphicStructures, int currentIndex, Structure* structure, const Identifier& ident, const PropertySlot& slot, size_t cachedOffset)
+        {
+            JIT jit(globalData, codeBlock);
+            jit.privateCompileGetByIdSelfList(stubInfo, polymorphicStructures, currentIndex, structure, ident, slot, cachedOffset);
+        }
+        static void compileGetByIdProtoList(JSGlobalData* globalData, CallFrame* callFrame, CodeBlock* codeBlock, StructureStubInfo* stubInfo, PolymorphicAccessStructureList* prototypeStructureList, int currentIndex, Structure* structure, Structure* prototypeStructure, const Identifier& ident, const PropertySlot& slot, size_t cachedOffset)
+        {
+            JIT jit(globalData, codeBlock);
+            jit.privateCompileGetByIdProtoList(stubInfo, prototypeStructureList, currentIndex, structure, prototypeStructure, ident, slot, cachedOffset, callFrame);
+        }
+        static void compileGetByIdChainList(JSGlobalData* globalData, CallFrame* callFrame, CodeBlock* codeBlock, StructureStubInfo* stubInfo, PolymorphicAccessStructureList* prototypeStructureList, int currentIndex, Structure* structure, StructureChain* chain, size_t count, const Identifier& ident, const PropertySlot& slot, size_t cachedOffset)
+        {
+            JIT jit(globalData, codeBlock);
+            jit.privateCompileGetByIdChainList(stubInfo, prototypeStructureList, currentIndex, structure, chain, count, ident, slot, cachedOffset, callFrame);
+        }
+
+        static void compileGetByIdChain(JSGlobalData* globalData, CallFrame* callFrame, CodeBlock* codeBlock, StructureStubInfo* stubInfo, Structure* structure, StructureChain* chain, size_t count, const Identifier& ident, const PropertySlot& slot, size_t cachedOffset, ReturnAddressPtr returnAddress)
+        {
+            JIT jit(globalData, codeBlock);
+            jit.privateCompileGetByIdChain(stubInfo, structure, chain, count, ident, slot, cachedOffset, returnAddress, callFrame);
+        }
+        
+        static void compilePutByIdTransition(JSGlobalData* globalData, CodeBlock* codeBlock, StructureStubInfo* stubInfo, Structure* oldStructure, Structure* newStructure, size_t cachedOffset, StructureChain* chain, ReturnAddressPtr returnAddress, bool direct)
+        {
+            JIT jit(globalData, codeBlock);
+            jit.privateCompilePutByIdTransition(stubInfo, oldStructure, newStructure, cachedOffset, chain, returnAddress, direct);
+        }
+
+        static PassRefPtr<ExecutableMemoryHandle> compileCTIMachineTrampolines(JSGlobalData* globalData, TrampolineStructure *trampolines)
+        {
+            if (!globalData->canUseJIT())
+                return 0;
+            JIT jit(globalData, 0);
+            return jit.privateCompileCTIMachineTrampolines(globalData, trampolines);
+        }
+
+        static CodeRef compileCTINativeCall(JSGlobalData* globalData, NativeFunction func)
+        {
+            if (!globalData->canUseJIT())
+                return CodeRef();
+            JIT jit(globalData, 0);
+            return jit.privateCompileCTINativeCall(globalData, func);
+        }
+
+        static void resetPatchGetById(RepatchBuffer&, StructureStubInfo*);
+        static void resetPatchPutById(RepatchBuffer&, StructureStubInfo*);
+        static void patchGetByIdSelf(CodeBlock* codeblock, StructureStubInfo*, Structure*, size_t cachedOffset, ReturnAddressPtr returnAddress);
+        static void patchPutByIdReplace(CodeBlock* codeblock, StructureStubInfo*, Structure*, size_t cachedOffset, ReturnAddressPtr returnAddress, bool direct);
+        static void patchMethodCallProto(JSGlobalData&, CodeBlock* codeblock, MethodCallLinkInfo&, JSObject*, Structure*, JSObject*, ReturnAddressPtr);
+
+        static void compilePatchGetArrayLength(JSGlobalData* globalData, CodeBlock* codeBlock, ReturnAddressPtr returnAddress)
+        {
+            JIT jit(globalData, codeBlock);
+            return jit.privateCompilePatchGetArrayLength(returnAddress);
+        }
+
+        static void linkFor(JSFunction* callee, CodeBlock* callerCodeBlock, CodeBlock* calleeCodeBlock, CodePtr, CallLinkInfo*, JSGlobalData*, CodeSpecializationKind);
+
+    private:
+        struct JSRInfo {
+            DataLabelPtr storeLocation;
+            Label target;
+
+            JSRInfo(DataLabelPtr storeLocation, Label targetLocation)
+                : storeLocation(storeLocation)
+                , target(targetLocation)
+            {
+            }
+        };
+
+        JIT(JSGlobalData*, CodeBlock* = 0);
+
+        void privateCompileMainPass();
+        void privateCompileLinkPass();
+        void privateCompileSlowCases();
+        JITCode privateCompile(CodePtr* functionEntryArityCheck);
+        void privateCompileGetByIdProto(StructureStubInfo*, Structure*, Structure* prototypeStructure, const Identifier&, const PropertySlot&, size_t cachedOffset, ReturnAddressPtr returnAddress, CallFrame* callFrame);
+        void privateCompileGetByIdSelfList(StructureStubInfo*, PolymorphicAccessStructureList*, int, Structure*, const Identifier&, const PropertySlot&, size_t cachedOffset);
+        void privateCompileGetByIdProtoList(StructureStubInfo*, PolymorphicAccessStructureList*, int, Structure*, Structure* prototypeStructure, const Identifier&, const PropertySlot&, size_t cachedOffset, CallFrame* callFrame);
+        void privateCompileGetByIdChainList(StructureStubInfo*, PolymorphicAccessStructureList*, int, Structure*, StructureChain* chain, size_t count, const Identifier&, const PropertySlot&, size_t cachedOffset, CallFrame* callFrame);
+        void privateCompileGetByIdChain(StructureStubInfo*, Structure*, StructureChain*, size_t count, const Identifier&, const PropertySlot&, size_t cachedOffset, ReturnAddressPtr returnAddress, CallFrame* callFrame);
+        void privateCompilePutByIdTransition(StructureStubInfo*, Structure*, Structure*, size_t cachedOffset, StructureChain*, ReturnAddressPtr returnAddress, bool direct);
+
+        PassRefPtr<ExecutableMemoryHandle> privateCompileCTIMachineTrampolines(JSGlobalData*, TrampolineStructure*);
+        Label privateCompileCTINativeCall(JSGlobalData*, bool isConstruct = false);
+        CodeRef privateCompileCTINativeCall(JSGlobalData*, NativeFunction);
+        void privateCompilePatchGetArrayLength(ReturnAddressPtr returnAddress);
+
+        static bool isDirectPutById(StructureStubInfo*);
+
+        void addSlowCase(Jump);
+        void addSlowCase(JumpList);
+        void addSlowCase();
+        void addJump(Jump, int);
+        void emitJumpSlowToHot(Jump, int);
+
+        void compileOpCall(OpcodeID, Instruction*, unsigned callLinkInfoIndex);
+        void compileOpCallSlowCase(OpcodeID, Instruction*, Vector<SlowCaseEntry>::iterator&, unsigned callLinkInfoIndex);
+        void compileLoadVarargs(Instruction*);
+        void compileCallEval();
+        void compileCallEvalSlowCase(Vector<SlowCaseEntry>::iterator&);
+
+        enum CompileOpStrictEqType { OpStrictEq, OpNStrictEq };
+        void compileOpStrictEq(Instruction* instruction, CompileOpStrictEqType type);
+        bool isOperandConstantImmediateDouble(unsigned src);
+        
+        void emitLoadDouble(int index, FPRegisterID value);
+        void emitLoadInt32ToDouble(int index, FPRegisterID value);
+        Jump emitJumpIfNotObject(RegisterID structureReg);
+        Jump emitJumpIfNotType(RegisterID baseReg, RegisterID scratchReg, JSType);
+
+        void testPrototype(JSValue, JumpList& failureCases);
+
+        enum WriteBarrierMode { UnconditionalWriteBarrier, ShouldFilterImmediates };
+        // value register in write barrier is used before any scratch registers
+        // so may safely be the same as either of the scratch registers.
+        void emitWriteBarrier(RegisterID owner, RegisterID valueTag, RegisterID scratch, RegisterID scratch2, WriteBarrierMode, WriteBarrierUseKind);
+        void emitWriteBarrier(JSCell* owner, RegisterID value, RegisterID scratch, WriteBarrierMode, WriteBarrierUseKind);
+
+        template<typename ClassType, typename StructureType> void emitAllocateBasicJSObject(StructureType, RegisterID result, RegisterID storagePtr);
+        template<typename T> void emitAllocateJSFinalObject(T structure, RegisterID result, RegisterID storagePtr);
+        void emitAllocateJSFunction(FunctionExecutable*, RegisterID scopeChain, RegisterID result, RegisterID storagePtr);
+        
+        enum ValueProfilingSiteKind { FirstProfilingSite, SubsequentProfilingSite };
+#if ENABLE(VALUE_PROFILER)
+        // This assumes that the value to profile is in regT0 and that regT3 is available for
+        // scratch.
+        void emitValueProfilingSite(ValueProfile*);
+        void emitValueProfilingSite(ValueProfilingSiteKind);
+#else
+        void emitValueProfilingSite(ValueProfilingSiteKind) { }
+#endif
+
+#if USE(JSVALUE32_64)
+        bool getOperandConstantImmediateInt(unsigned op1, unsigned op2, unsigned& op, int32_t& constant);
+
+        void emitLoadTag(int index, RegisterID tag);
+        void emitLoadPayload(int index, RegisterID payload);
+
+        void emitLoad(const JSValue& v, RegisterID tag, RegisterID payload);
+        void emitLoad(int index, RegisterID tag, RegisterID payload, RegisterID base = callFrameRegister);
+        void emitLoad2(int index1, RegisterID tag1, RegisterID payload1, int index2, RegisterID tag2, RegisterID payload2);
+
+        void emitStore(int index, RegisterID tag, RegisterID payload, RegisterID base = callFrameRegister);
+        void emitStore(int index, const JSValue constant, RegisterID base = callFrameRegister);
+        void emitStoreInt32(int index, RegisterID payload, bool indexIsInt32 = false);
+        void emitStoreInt32(int index, TrustedImm32 payload, bool indexIsInt32 = false);
+        void emitStoreAndMapInt32(int index, RegisterID tag, RegisterID payload, bool indexIsInt32, size_t opcodeLength);
+        void emitStoreCell(int index, RegisterID payload, bool indexIsCell = false);
+        void emitStoreBool(int index, RegisterID payload, bool indexIsBool = false);
+        void emitStoreDouble(int index, FPRegisterID value);
+
+        bool isLabeled(unsigned bytecodeOffset);
+        void map(unsigned bytecodeOffset, int virtualRegisterIndex, RegisterID tag, RegisterID payload);
+        void unmap(RegisterID);
+        void unmap();
+        bool isMapped(int virtualRegisterIndex);
+        bool getMappedPayload(int virtualRegisterIndex, RegisterID& payload);
+        bool getMappedTag(int virtualRegisterIndex, RegisterID& tag);
+
+        void emitJumpSlowCaseIfNotJSCell(int virtualRegisterIndex);
+        void emitJumpSlowCaseIfNotJSCell(int virtualRegisterIndex, RegisterID tag);
+
+        void compileGetByIdHotPath();
+        void compileGetByIdSlowCase(int resultVReg, int baseVReg, Identifier* ident, Vector<SlowCaseEntry>::iterator& iter, bool isMethodCheck = false);
+        void compileGetDirectOffset(RegisterID base, RegisterID resultTag, RegisterID resultPayload, size_t cachedOffset);
+        void compileGetDirectOffset(JSObject* base, RegisterID resultTag, RegisterID resultPayload, size_t cachedOffset);
+        void compileGetDirectOffset(RegisterID base, RegisterID resultTag, RegisterID resultPayload, RegisterID offset);
+        void compilePutDirectOffset(RegisterID base, RegisterID valueTag, RegisterID valuePayload, size_t cachedOffset);
+
+        // Arithmetic opcode helpers
+        void emitAdd32Constant(unsigned dst, unsigned op, int32_t constant, ResultType opType);
+        void emitSub32Constant(unsigned dst, unsigned op, int32_t constant, ResultType opType);
+        void emitBinaryDoubleOp(OpcodeID, unsigned dst, unsigned op1, unsigned op2, OperandTypes, JumpList& notInt32Op1, JumpList& notInt32Op2, bool op1IsInRegisters = true, bool op2IsInRegisters = true);
+
+#if CPU(X86)
+        // These architecture specific value are used to enable patching - see comment on op_put_by_id.
+        static const int patchOffsetPutByIdStructure = 7;
+        static const int patchOffsetPutByIdPropertyMapOffset1 = 22;
+        static const int patchOffsetPutByIdPropertyMapOffset2 = 28;
+        // These architecture specific value are used to enable patching - see comment on op_get_by_id.
+        static const int patchOffsetGetByIdStructure = 7;
+        static const int patchOffsetGetByIdBranchToSlowCase = 13;
+        static const int patchOffsetGetByIdPropertyMapOffset1 = 19;
+        static const int patchOffsetGetByIdPropertyMapOffset2 = 22;
+        static const int patchOffsetGetByIdPutResult = 22;
+#if ENABLE(OPCODE_SAMPLING)
+        static const int patchOffsetGetByIdSlowCaseCall = 37;
+#else
+        static const int patchOffsetGetByIdSlowCaseCall = 33;
+#endif
+        static const int patchOffsetOpCallCompareToJump = 6;
+
+        static const int patchOffsetMethodCheckProtoObj = 11;
+        static const int patchOffsetMethodCheckProtoStruct = 18;
+        static const int patchOffsetMethodCheckPutFunction = 29;
+#elif CPU(ARM_TRADITIONAL)
+        // These architecture specific value are used to enable patching - see comment on op_put_by_id.
+        static const int patchOffsetPutByIdStructure = 4;
+        static const int patchOffsetPutByIdPropertyMapOffset1 = 20;
+        static const int patchOffsetPutByIdPropertyMapOffset2 = 28;
+        // These architecture specific value are used to enable patching - see comment on op_get_by_id.
+        static const int patchOffsetGetByIdStructure = 4;
+        static const int patchOffsetGetByIdBranchToSlowCase = 16;
+        static const int patchOffsetGetByIdPropertyMapOffset1 = 20;
+        static const int patchOffsetGetByIdPropertyMapOffset2 = 28;
+        static const int patchOffsetGetByIdPutResult = 36;
+#if ENABLE(OPCODE_SAMPLING)
+        #error "OPCODE_SAMPLING is not yet supported"
+#else
+        static const int patchOffsetGetByIdSlowCaseCall = 40;
+#endif
+        static const int patchOffsetOpCallCompareToJump = 12;
+
+        static const int patchOffsetMethodCheckProtoObj = 12;
+        static const int patchOffsetMethodCheckProtoStruct = 20;
+        static const int patchOffsetMethodCheckPutFunction = 32;
+
+        // sequenceOpCall
+        static const int sequenceOpCallInstructionSpace = 12;
+        static const int sequenceOpCallConstantSpace = 2;
+        // sequenceMethodCheck
+        static const int sequenceMethodCheckInstructionSpace = 40;
+        static const int sequenceMethodCheckConstantSpace = 6;
+        // sequenceGetByIdHotPath
+        static const int sequenceGetByIdHotPathInstructionSpace = 36;
+        static const int sequenceGetByIdHotPathConstantSpace = 4;
+        // sequenceGetByIdSlowCase
+        static const int sequenceGetByIdSlowCaseInstructionSpace = 56;
+        static const int sequenceGetByIdSlowCaseConstantSpace = 3;
+        // sequencePutById
+        static const int sequencePutByIdInstructionSpace = 36;
+        static const int sequencePutByIdConstantSpace = 4;
+#elif CPU(ARM_THUMB2)
+        // These architecture specific value are used to enable patching - see comment on op_put_by_id.
+        static const int patchOffsetPutByIdStructure = 10;
+        static const int patchOffsetPutByIdPropertyMapOffset1 = 36;
+        static const int patchOffsetPutByIdPropertyMapOffset2 = 48;
+        // These architecture specific value are used to enable patching - see comment on op_get_by_id.
+        static const int patchOffsetGetByIdStructure = 10;
+        static const int patchOffsetGetByIdBranchToSlowCase = 26;
+        static const int patchOffsetGetByIdPropertyMapOffset1 = 28;
+        static const int patchOffsetGetByIdPropertyMapOffset2 = 30;
+        static const int patchOffsetGetByIdPutResult = 32;
+#if ENABLE(OPCODE_SAMPLING)
+        #error "OPCODE_SAMPLING is not yet supported"
+#else
+        static const int patchOffsetGetByIdSlowCaseCall = 40;
+#endif
+        static const int patchOffsetOpCallCompareToJump = 16;
+
+        static const int patchOffsetMethodCheckProtoObj = 24;
+        static const int patchOffsetMethodCheckProtoStruct = 34;
+        static const int patchOffsetMethodCheckPutFunction = 58;
+
+        // sequenceOpCall
+        static const int sequenceOpCallInstructionSpace = 12;
+        static const int sequenceOpCallConstantSpace = 2;
+        // sequenceMethodCheck
+        static const int sequenceMethodCheckInstructionSpace = 40;
+        static const int sequenceMethodCheckConstantSpace = 6;
+        // sequenceGetByIdHotPath
+        static const int sequenceGetByIdHotPathInstructionSpace = 36;
+        static const int sequenceGetByIdHotPathConstantSpace = 4;
+        // sequenceGetByIdSlowCase
+        static const int sequenceGetByIdSlowCaseInstructionSpace = 40;
+        static const int sequenceGetByIdSlowCaseConstantSpace = 2;
+        // sequencePutById
+        static const int sequencePutByIdInstructionSpace = 36;
+        static const int sequencePutByIdConstantSpace = 4;
+#elif CPU(MIPS)
+#if WTF_MIPS_ISA(1)
+        static const int patchOffsetPutByIdStructure = 16;
+        static const int patchOffsetPutByIdPropertyMapOffset1 = 56;
+        static const int patchOffsetPutByIdPropertyMapOffset2 = 72;
+        static const int patchOffsetGetByIdStructure = 16;
+        static const int patchOffsetGetByIdBranchToSlowCase = 48;
+        static const int patchOffsetGetByIdPropertyMapOffset1 = 56;
+        static const int patchOffsetGetByIdPropertyMapOffset2 = 76;
+        static const int patchOffsetGetByIdPutResult = 96;
+#if ENABLE(OPCODE_SAMPLING)
+        #error "OPCODE_SAMPLING is not yet supported"
+#else
+        static const int patchOffsetGetByIdSlowCaseCall = 56;
+#endif
+        static const int patchOffsetOpCallCompareToJump = 32;
+        static const int patchOffsetMethodCheckProtoObj = 32;
+        static const int patchOffsetMethodCheckProtoStruct = 56;
+        static const int patchOffsetMethodCheckPutFunction = 88;
+#else // WTF_MIPS_ISA(1)
+        static const int patchOffsetPutByIdStructure = 12;
+        static const int patchOffsetPutByIdPropertyMapOffset1 = 48;
+        static const int patchOffsetPutByIdPropertyMapOffset2 = 64;
+        static const int patchOffsetGetByIdStructure = 12;
+        static const int patchOffsetGetByIdBranchToSlowCase = 44;
+        static const int patchOffsetGetByIdPropertyMapOffset1 = 48;
+        static const int patchOffsetGetByIdPropertyMapOffset2 = 64;
+        static const int patchOffsetGetByIdPutResult = 80;
+#if ENABLE(OPCODE_SAMPLING)
+        #error "OPCODE_SAMPLING is not yet supported"
+#else
+        static const int patchOffsetGetByIdSlowCaseCall = 56;
+#endif
+        static const int patchOffsetOpCallCompareToJump = 32;
+        static const int patchOffsetMethodCheckProtoObj = 32;
+        static const int patchOffsetMethodCheckProtoStruct = 52;
+        static const int patchOffsetMethodCheckPutFunction = 84;
+#endif
+#elif CPU(SH4)
+       // These architecture specific value are used to enable patching - see comment on op_put_by_id.
+        static const int patchOffsetGetByIdStructure = 6;
+        static const int patchOffsetPutByIdPropertyMapOffset = 24;
+        static const int patchOffsetPutByIdStructure = 6;
+        // These architecture specific value are used to enable patching - see comment on op_get_by_id.
+        static const int patchOffsetGetByIdBranchToSlowCase = 10;
+        static const int patchOffsetGetByIdPropertyMapOffset = 24;
+        static const int patchOffsetGetByIdPutResult = 24;
+
+        // sequenceOpCall
+        static const int sequenceOpCallInstructionSpace = 12;
+        static const int sequenceOpCallConstantSpace = 2;
+        // sequenceMethodCheck
+        static const int sequenceMethodCheckInstructionSpace = 40;
+        static const int sequenceMethodCheckConstantSpace = 6;
+        // sequenceGetByIdHotPath
+        static const int sequenceGetByIdHotPathInstructionSpace = 36;
+        static const int sequenceGetByIdHotPathConstantSpace = 5;
+        // sequenceGetByIdSlowCase
+        static const int sequenceGetByIdSlowCaseInstructionSpace = 30;
+        static const int sequenceGetByIdSlowCaseConstantSpace = 3;
+        // sequencePutById
+        static const int sequencePutByIdInstructionSpace = 36;
+        static const int sequencePutByIdConstantSpace = 5;
+
+        static const int patchOffsetGetByIdPropertyMapOffset1 = 20;
+        static const int patchOffsetGetByIdPropertyMapOffset2 = 22;
+
+        static const int patchOffsetPutByIdPropertyMapOffset1 = 20;
+        static const int patchOffsetPutByIdPropertyMapOffset2 = 26;
+
+#if ENABLE(OPCODE_SAMPLING)
+        static const int patchOffsetGetByIdSlowCaseCall = 0; // FIMXE
+#else
+        static const int patchOffsetGetByIdSlowCaseCall = 26;
+#endif
+        static const int patchOffsetOpCallCompareToJump = 4;
+
+        static const int patchOffsetMethodCheckProtoObj = 12;
+        static const int patchOffsetMethodCheckProtoStruct = 20;
+        static const int patchOffsetMethodCheckPutFunction = 32;
+#else
+#error "JSVALUE32_64 not supported on this platform."
+#endif
+
+#else // USE(JSVALUE32_64)
+        void emitGetVirtualRegister(int src, RegisterID dst);
+        void emitGetVirtualRegisters(int src1, RegisterID dst1, int src2, RegisterID dst2);
+        void emitPutVirtualRegister(unsigned dst, RegisterID from = regT0);
+        void emitStoreCell(unsigned dst, RegisterID payload, bool /* only used in JSValue32_64 */ = false)
+        {
+            emitPutVirtualRegister(dst, payload);
+        }
+
+        int32_t getConstantOperandImmediateInt(unsigned src);
+
+        void killLastResultRegister();
+
+        Jump emitJumpIfJSCell(RegisterID);
+        Jump emitJumpIfBothJSCells(RegisterID, RegisterID, RegisterID);
+        void emitJumpSlowCaseIfJSCell(RegisterID);
+        Jump emitJumpIfNotJSCell(RegisterID);
+        void emitJumpSlowCaseIfNotJSCell(RegisterID);
+        void emitJumpSlowCaseIfNotJSCell(RegisterID, int VReg);
+#if USE(JSVALUE32_64)
+        JIT::Jump emitJumpIfImmediateNumber(RegisterID reg)
+        {
+            return emitJumpIfImmediateInteger(reg);
+        }
+        
+        JIT::Jump emitJumpIfNotImmediateNumber(RegisterID reg)
+        {
+            return emitJumpIfNotImmediateInteger(reg);
+        }
+#endif
+        Jump emitJumpIfImmediateInteger(RegisterID);
+        Jump emitJumpIfNotImmediateInteger(RegisterID);
+        Jump emitJumpIfNotImmediateIntegers(RegisterID, RegisterID, RegisterID);
+        void emitJumpSlowCaseIfNotImmediateInteger(RegisterID);
+        void emitJumpSlowCaseIfNotImmediateNumber(RegisterID);
+        void emitJumpSlowCaseIfNotImmediateIntegers(RegisterID, RegisterID, RegisterID);
+
+#if USE(JSVALUE32_64)
+        void emitFastArithDeTagImmediate(RegisterID);
+        Jump emitFastArithDeTagImmediateJumpIfZero(RegisterID);
+#endif
+        void emitFastArithReTagImmediate(RegisterID src, RegisterID dest);
+        void emitFastArithIntToImmNoCheck(RegisterID src, RegisterID dest);
+
+        void emitTagAsBoolImmediate(RegisterID reg);
+        void compileBinaryArithOp(OpcodeID, unsigned dst, unsigned src1, unsigned src2, OperandTypes opi);
+#if USE(JSVALUE64)
+        void compileBinaryArithOpSlowCase(OpcodeID, Vector<SlowCaseEntry>::iterator&, unsigned dst, unsigned src1, unsigned src2, OperandTypes, bool op1HasImmediateIntFastCase, bool op2HasImmediateIntFastCase);
+#else
+        void compileBinaryArithOpSlowCase(OpcodeID, Vector<SlowCaseEntry>::iterator&, unsigned dst, unsigned src1, unsigned src2, OperandTypes);
+#endif
+
+        void compileGetByIdHotPath(int baseVReg, Identifier*);
+        void compileGetByIdSlowCase(int resultVReg, int baseVReg, Identifier* ident, Vector<SlowCaseEntry>::iterator& iter, bool isMethodCheck = false);
+        void compileGetDirectOffset(RegisterID base, RegisterID result, size_t cachedOffset);
+        void compileGetDirectOffset(JSObject* base, RegisterID result, size_t cachedOffset);
+        void compileGetDirectOffset(RegisterID base, RegisterID result, RegisterID offset, RegisterID scratch);
+        void compilePutDirectOffset(RegisterID base, RegisterID value, size_t cachedOffset);
+
+#if CPU(X86_64)
+        // These architecture specific value are used to enable patching - see comment on op_put_by_id.
+        static const int patchOffsetPutByIdStructure = 10;
+        static const int patchOffsetPutByIdPropertyMapOffset = 31;
+        // These architecture specific value are used to enable patching - see comment on op_get_by_id.
+        static const int patchOffsetGetByIdStructure = 10;
+        static const int patchOffsetGetByIdBranchToSlowCase = 20;
+        static const int patchOffsetGetByIdPropertyMapOffset = 28;
+        static const int patchOffsetGetByIdPutResult = 28;
+#if ENABLE(OPCODE_SAMPLING)
+        static const int patchOffsetGetByIdSlowCaseCall = 64;
+#else
+        static const int patchOffsetGetByIdSlowCaseCall = 54;
+#endif
+        static const int patchOffsetOpCallCompareToJump = 9;
+
+        static const int patchOffsetMethodCheckProtoObj = 20;
+        static const int patchOffsetMethodCheckProtoStruct = 30;
+        static const int patchOffsetMethodCheckPutFunction = 50;
+#elif CPU(X86)
+        // These architecture specific value are used to enable patching - see comment on op_put_by_id.
+        static const int patchOffsetPutByIdStructure = 7;
+        static const int patchOffsetPutByIdPropertyMapOffset = 22;
+        // These architecture specific value are used to enable patching - see comment on op_get_by_id.
+        static const int patchOffsetGetByIdStructure = 7;
+        static const int patchOffsetGetByIdBranchToSlowCase = 13;
+        static const int patchOffsetGetByIdPropertyMapOffset = 22;
+        static const int patchOffsetGetByIdPutResult = 22;
+#if ENABLE(OPCODE_SAMPLING)
+        static const int patchOffsetGetByIdSlowCaseCall = 33;
+#else
+        static const int patchOffsetGetByIdSlowCaseCall = 23;
+#endif
+        static const int patchOffsetOpCallCompareToJump = 6;
+
+        static const int patchOffsetMethodCheckProtoObj = 11;
+        static const int patchOffsetMethodCheckProtoStruct = 18;
+        static const int patchOffsetMethodCheckPutFunction = 29;
+#elif CPU(ARM_THUMB2)
+        // These architecture specific value are used to enable patching - see comment on op_put_by_id.
+        static const int patchOffsetPutByIdStructure = 10;
+        static const int patchOffsetPutByIdPropertyMapOffset = 46;
+        // These architecture specific value are used to enable patching - see comment on op_get_by_id.
+        static const int patchOffsetGetByIdStructure = 10;
+        static const int patchOffsetGetByIdBranchToSlowCase = 26;
+        static const int patchOffsetGetByIdPropertyMapOffset = 46;
+        static const int patchOffsetGetByIdPutResult = 50;
+#if ENABLE(OPCODE_SAMPLING)
+        static const int patchOffsetGetByIdSlowCaseCall = 0; // FIMXE
+#else
+        static const int patchOffsetGetByIdSlowCaseCall = 28;
+#endif
+        static const int patchOffsetOpCallCompareToJump = 16;
+
+        static const int patchOffsetMethodCheckProtoObj = 24;
+        static const int patchOffsetMethodCheckProtoStruct = 34;
+        static const int patchOffsetMethodCheckPutFunction = 58;
+#elif CPU(ARM_TRADITIONAL)
+        // These architecture specific value are used to enable patching - see comment on op_put_by_id.
+        static const int patchOffsetPutByIdStructure = 4;
+        static const int patchOffsetPutByIdPropertyMapOffset = 20;
+        // These architecture specific value are used to enable patching - see comment on op_get_by_id.
+        static const int patchOffsetGetByIdStructure = 4;
+        static const int patchOffsetGetByIdBranchToSlowCase = 16;
+        static const int patchOffsetGetByIdPropertyMapOffset = 20;
+        static const int patchOffsetGetByIdPutResult = 28;
+#if ENABLE(OPCODE_SAMPLING)
+        #error "OPCODE_SAMPLING is not yet supported"
+#else
+        static const int patchOffsetGetByIdSlowCaseCall = 28;
+#endif
+        static const int patchOffsetOpCallCompareToJump = 12;
+
+        static const int patchOffsetMethodCheckProtoObj = 12;
+        static const int patchOffsetMethodCheckProtoStruct = 20;
+        static const int patchOffsetMethodCheckPutFunction = 32;
+
+        // sequenceOpCall
+        static const int sequenceOpCallInstructionSpace = 12;
+        static const int sequenceOpCallConstantSpace = 2;
+        // sequenceMethodCheck
+        static const int sequenceMethodCheckInstructionSpace = 40;
+        static const int sequenceMethodCheckConstantSpace = 6;
+        // sequenceGetByIdHotPath
+        static const int sequenceGetByIdHotPathInstructionSpace = 28;
+        static const int sequenceGetByIdHotPathConstantSpace = 3;
+        // sequenceGetByIdSlowCase
+        static const int sequenceGetByIdSlowCaseInstructionSpace = 32;
+        static const int sequenceGetByIdSlowCaseConstantSpace = 2;
+        // sequencePutById
+        static const int sequencePutByIdInstructionSpace = 28;
+        static const int sequencePutByIdConstantSpace = 3;
+#elif CPU(MIPS)
+#if WTF_MIPS_ISA(1)
+        static const int patchOffsetPutByIdStructure = 16;
+        static const int patchOffsetPutByIdPropertyMapOffset = 68;
+        static const int patchOffsetGetByIdStructure = 16;
+        static const int patchOffsetGetByIdBranchToSlowCase = 48;
+        static const int patchOffsetGetByIdPropertyMapOffset = 68;
+        static const int patchOffsetGetByIdPutResult = 88;
+#if ENABLE(OPCODE_SAMPLING)
+        #error "OPCODE_SAMPLING is not yet supported"
+#else
+        static const int patchOffsetGetByIdSlowCaseCall = 40;
+#endif
+        static const int patchOffsetOpCallCompareToJump = 32;
+        static const int patchOffsetMethodCheckProtoObj = 32;
+        static const int patchOffsetMethodCheckProtoStruct = 56;
+        static const int patchOffsetMethodCheckPutFunction = 88;
+#else // WTF_MIPS_ISA(1)
+        static const int patchOffsetPutByIdStructure = 12;
+        static const int patchOffsetPutByIdPropertyMapOffset = 60;
+        static const int patchOffsetGetByIdStructure = 12;
+        static const int patchOffsetGetByIdBranchToSlowCase = 44;
+        static const int patchOffsetGetByIdPropertyMapOffset = 60;
+        static const int patchOffsetGetByIdPutResult = 76;
+#if ENABLE(OPCODE_SAMPLING)
+        #error "OPCODE_SAMPLING is not yet supported"
+#else
+        static const int patchOffsetGetByIdSlowCaseCall = 40;
+#endif
+        static const int patchOffsetOpCallCompareToJump = 32;
+        static const int patchOffsetMethodCheckProtoObj = 32;
+        static const int patchOffsetMethodCheckProtoStruct = 52;
+        static const int patchOffsetMethodCheckPutFunction = 84;
+#endif
+#endif
+#endif // USE(JSVALUE32_64)
+
+#if (defined(ASSEMBLER_HAS_CONSTANT_POOL) && ASSEMBLER_HAS_CONSTANT_POOL)
+#define BEGIN_UNINTERRUPTED_SEQUENCE(name) do { beginUninterruptedSequence(name ## InstructionSpace, name ## ConstantSpace); } while (false)
+#define END_UNINTERRUPTED_SEQUENCE_FOR_PUT(name, dst) do { endUninterruptedSequence(name ## InstructionSpace, name ## ConstantSpace, dst); } while (false)
+#define END_UNINTERRUPTED_SEQUENCE(name) END_UNINTERRUPTED_SEQUENCE_FOR_PUT(name, 0)
+
+        void beginUninterruptedSequence(int, int);
+        void endUninterruptedSequence(int, int, int);
+
+#else
+#define BEGIN_UNINTERRUPTED_SEQUENCE(name)  do { beginUninterruptedSequence(); } while (false)
+#define END_UNINTERRUPTED_SEQUENCE(name)  do { endUninterruptedSequence(); } while (false)
+#define END_UNINTERRUPTED_SEQUENCE_FOR_PUT(name, dst) do { endUninterruptedSequence(); } while (false)
+#endif
+
+        void emit_compareAndJump(OpcodeID, unsigned op1, unsigned op2, unsigned target, RelationalCondition);
+        void emit_compareAndJumpSlow(unsigned op1, unsigned op2, unsigned target, DoubleCondition, int (JIT_STUB *stub)(STUB_ARGS_DECLARATION), bool invert, Vector<SlowCaseEntry>::iterator&);
+
+        void emit_op_add(Instruction*);
+        void emit_op_bitand(Instruction*);
+        void emit_op_bitnot(Instruction*);
+        void emit_op_bitor(Instruction*);
+        void emit_op_bitxor(Instruction*);
+        void emit_op_call(Instruction*);
+        void emit_op_call_eval(Instruction*);
+        void emit_op_call_varargs(Instruction*);
+        void emit_op_call_put_result(Instruction*);
+        void emit_op_catch(Instruction*);
+        void emit_op_construct(Instruction*);
+        void emit_op_get_callee(Instruction*);
+        void emit_op_create_this(Instruction*);
+        void emit_op_convert_this(Instruction*);
+        void emit_op_create_arguments(Instruction*);
+        void emit_op_debug(Instruction*);
+        void emit_op_del_by_id(Instruction*);
+        void emit_op_div(Instruction*);
+        void emit_op_end(Instruction*);
+        void emit_op_enter(Instruction*);
+        void emit_op_create_activation(Instruction*);
+        void emit_op_eq(Instruction*);
+        void emit_op_eq_null(Instruction*);
+        void emit_op_get_by_id(Instruction*);
+        void emit_op_get_arguments_length(Instruction*);
+        void emit_op_get_by_val(Instruction*);
+        void emit_op_get_argument_by_val(Instruction*);
+        void emit_op_get_by_pname(Instruction*);
+        void emit_op_get_global_var(Instruction*);
+        void emit_op_get_scoped_var(Instruction*);
+        void emit_op_init_lazy_reg(Instruction*);
+        void emit_op_check_has_instance(Instruction*);
+        void emit_op_instanceof(Instruction*);
+        void emit_op_jeq_null(Instruction*);
+        void emit_op_jfalse(Instruction*);
+        void emit_op_jmp(Instruction*);
+        void emit_op_jmp_scopes(Instruction*);
+        void emit_op_jneq_null(Instruction*);
+        void emit_op_jneq_ptr(Instruction*);
+        void emit_op_jless(Instruction*);
+        void emit_op_jlesseq(Instruction*);
+        void emit_op_jgreater(Instruction*);
+        void emit_op_jgreatereq(Instruction*);
+        void emit_op_jnless(Instruction*);
+        void emit_op_jnlesseq(Instruction*);
+        void emit_op_jngreater(Instruction*);
+        void emit_op_jngreatereq(Instruction*);
+        void emit_op_jsr(Instruction*);
+        void emit_op_jtrue(Instruction*);
+        void emit_op_loop(Instruction*);
+        void emit_op_loop_hint(Instruction*);
+        void emit_op_loop_if_less(Instruction*);
+        void emit_op_loop_if_lesseq(Instruction*);
+        void emit_op_loop_if_greater(Instruction*);
+        void emit_op_loop_if_greatereq(Instruction*);
+        void emit_op_loop_if_true(Instruction*);
+        void emit_op_loop_if_false(Instruction*);
+        void emit_op_lshift(Instruction*);
+        void emit_op_method_check(Instruction*);
+        void emit_op_mod(Instruction*);
+        void emit_op_mov(Instruction*);
+        void emit_op_mul(Instruction*);
+        void emit_op_negate(Instruction*);
+        void emit_op_neq(Instruction*);
+        void emit_op_neq_null(Instruction*);
+        void emit_op_new_array(Instruction*);
+        void emit_op_new_array_buffer(Instruction*);
+        void emit_op_new_func(Instruction*);
+        void emit_op_new_func_exp(Instruction*);
+        void emit_op_new_object(Instruction*);
+        void emit_op_new_regexp(Instruction*);
+        void emit_op_get_pnames(Instruction*);
+        void emit_op_next_pname(Instruction*);
+        void emit_op_not(Instruction*);
+        void emit_op_nstricteq(Instruction*);
+        void emit_op_pop_scope(Instruction*);
+        void emit_op_post_dec(Instruction*);
+        void emit_op_post_inc(Instruction*);
+        void emit_op_pre_dec(Instruction*);
+        void emit_op_pre_inc(Instruction*);
+        void emit_op_profile_did_call(Instruction*);
+        void emit_op_profile_will_call(Instruction*);
+        void emit_op_push_new_scope(Instruction*);
+        void emit_op_push_scope(Instruction*);
+        void emit_op_put_by_id(Instruction*);
+        void emit_op_put_by_index(Instruction*);
+        void emit_op_put_by_val(Instruction*);
+        void emit_op_put_getter(Instruction*);
+        void emit_op_put_global_var(Instruction*);
+        void emit_op_put_scoped_var(Instruction*);
+        void emit_op_put_setter(Instruction*);
+        void emit_op_resolve(Instruction*);
+        void emit_op_resolve_base(Instruction*);
+        void emit_op_ensure_property_exists(Instruction*);
+        void emit_op_resolve_global(Instruction*, bool dynamic = false);
+        void emit_op_resolve_global_dynamic(Instruction*);
+        void emit_op_resolve_skip(Instruction*);
+        void emit_op_resolve_with_base(Instruction*);
+        void emit_op_resolve_with_this(Instruction*);
+        void emit_op_ret(Instruction*);
+        void emit_op_ret_object_or_this(Instruction*);
+        void emit_op_rshift(Instruction*);
+        void emit_op_sret(Instruction*);
+        void emit_op_strcat(Instruction*);
+        void emit_op_stricteq(Instruction*);
+        void emit_op_sub(Instruction*);
+        void emit_op_switch_char(Instruction*);
+        void emit_op_switch_imm(Instruction*);
+        void emit_op_switch_string(Instruction*);
+        void emit_op_tear_off_activation(Instruction*);
+        void emit_op_tear_off_arguments(Instruction*);
+        void emit_op_throw(Instruction*);
+        void emit_op_throw_reference_error(Instruction*);
+        void emit_op_to_jsnumber(Instruction*);
+        void emit_op_to_primitive(Instruction*);
+        void emit_op_unexpected_load(Instruction*);
+        void emit_op_urshift(Instruction*);
+#if ENABLE(JIT_USE_SOFT_MODULO)
+        void softModulo();
+#endif
+
+        void emitSlow_op_add(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_bitand(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_bitnot(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_bitor(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_bitxor(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_call(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_call_eval(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_call_varargs(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_construct(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_convert_this(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_create_this(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_div(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_eq(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_get_by_id(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_get_arguments_length(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_get_by_val(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_get_argument_by_val(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_get_by_pname(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_check_has_instance(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_instanceof(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_jfalse(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_jless(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_jlesseq(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_jgreater(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_jgreatereq(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_jnless(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_jnlesseq(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_jngreater(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_jngreatereq(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_jtrue(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_loop_if_less(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_loop_if_lesseq(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_loop_if_greater(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_loop_if_greatereq(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_loop_if_true(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_loop_if_false(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_lshift(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_method_check(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_mod(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_mul(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_negate(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_neq(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_new_object(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_not(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_nstricteq(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_post_dec(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_post_inc(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_pre_dec(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_pre_inc(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_put_by_id(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_put_by_val(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_resolve_global(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_resolve_global_dynamic(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_rshift(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_stricteq(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_sub(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_to_jsnumber(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_to_primitive(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_urshift(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_new_func(Instruction*, Vector<SlowCaseEntry>::iterator&);
+        void emitSlow_op_new_func_exp(Instruction*, Vector<SlowCaseEntry>::iterator&);
+
+        
+        void emitRightShift(Instruction*, bool isUnsigned);
+        void emitRightShiftSlowCase(Instruction*, Vector<SlowCaseEntry>::iterator&, bool isUnsigned);
+
+        /* This function is deprecated. */
+        void emitGetJITStubArg(unsigned argumentNumber, RegisterID dst);
+
+        void emitInitRegister(unsigned dst);
+
+        void emitPutToCallFrameHeader(RegisterID from, RegisterFile::CallFrameHeaderEntry entry);
+        void emitPutCellToCallFrameHeader(RegisterID from, RegisterFile::CallFrameHeaderEntry);
+        void emitPutIntToCallFrameHeader(RegisterID from, RegisterFile::CallFrameHeaderEntry);
+        void emitPutImmediateToCallFrameHeader(void* value, RegisterFile::CallFrameHeaderEntry entry);
+        void emitGetFromCallFrameHeaderPtr(RegisterFile::CallFrameHeaderEntry entry, RegisterID to, RegisterID from = callFrameRegister);
+        void emitGetFromCallFrameHeader32(RegisterFile::CallFrameHeaderEntry entry, RegisterID to, RegisterID from = callFrameRegister);
+
+        JSValue getConstantOperand(unsigned src);
+        bool isOperandConstantImmediateInt(unsigned src);
+        bool isOperandConstantImmediateChar(unsigned src);
+
+        bool atJumpTarget();
+
+        Jump getSlowCase(Vector<SlowCaseEntry>::iterator& iter)
+        {
+            return iter++->from;
+        }
+        void linkSlowCase(Vector<SlowCaseEntry>::iterator& iter)
+        {
+            iter->from.link(this);
+            ++iter;
+        }
+        void linkDummySlowCase(Vector<SlowCaseEntry>::iterator& iter)
+        {
+            ASSERT(!iter->from.isSet());
+            ++iter;
+        }
+        void linkSlowCaseIfNotJSCell(Vector<SlowCaseEntry>::iterator&, int virtualRegisterIndex);
+
+        Jump checkStructure(RegisterID reg, Structure* structure);
+
+        void restoreArgumentReference();
+        void restoreArgumentReferenceForTrampoline();
+        void updateTopCallFrame();
+
+        Call emitNakedCall(CodePtr function = CodePtr());
+
+        void preserveReturnAddressAfterCall(RegisterID);
+        void restoreReturnAddressBeforeReturn(RegisterID);
+        void restoreReturnAddressBeforeReturn(Address);
+
+        // Loads the character value of a single character string into dst.
+        void emitLoadCharacterString(RegisterID src, RegisterID dst, JumpList& failures);
+        
+        enum OptimizationCheckKind { LoopOptimizationCheck, RetOptimizationCheck };
+#if ENABLE(DFG_JIT)
+        void emitOptimizationCheck(OptimizationCheckKind);
+#else
+        void emitOptimizationCheck(OptimizationCheckKind) { }
+#endif
+        
+        void emitTimeoutCheck();
+#ifndef NDEBUG
+        void printBytecodeOperandTypes(unsigned src1, unsigned src2);
+#endif
+
+#if ENABLE(SAMPLING_FLAGS)
+        void setSamplingFlag(int32_t);
+        void clearSamplingFlag(int32_t);
+#endif
+
+#if ENABLE(SAMPLING_COUNTERS)
+        void emitCount(AbstractSamplingCounter&, int32_t = 1);
+#endif
+
+#if ENABLE(OPCODE_SAMPLING)
+        void sampleInstruction(Instruction*, bool = false);
+#endif
+
+#if ENABLE(CODEBLOCK_SAMPLING)
+        void sampleCodeBlock(CodeBlock*);
+#else
+        void sampleCodeBlock(CodeBlock*) {}
+#endif
+
+#if ENABLE(DFG_JIT)
+        bool canBeOptimized() { return m_canBeOptimized; }
+        bool shouldEmitProfiling() { return m_canBeOptimized; }
+#else
+        bool canBeOptimized() { return false; }
+        // Enables use of value profiler with tiered compilation turned off,
+        // in which case all code gets profiled.
+        bool shouldEmitProfiling() { return true; }
+#endif
+
+        Interpreter* m_interpreter;
+        JSGlobalData* m_globalData;
+        CodeBlock* m_codeBlock;
+
+        Vector<CallRecord> m_calls;
+        Vector<Label> m_labels;
+        Vector<PropertyStubCompilationInfo> m_propertyAccessCompilationInfo;
+        Vector<StructureStubCompilationInfo> m_callStructureStubCompilationInfo;
+        Vector<MethodCallCompilationInfo> m_methodCallCompilationInfo;
+        Vector<JumpTable> m_jmpTable;
+
+        unsigned m_bytecodeOffset;
+        Vector<JSRInfo> m_jsrSites;
+        Vector<SlowCaseEntry> m_slowCases;
+        Vector<SwitchRecord> m_switches;
+
+        unsigned m_propertyAccessInstructionIndex;
+        unsigned m_globalResolveInfoIndex;
+        unsigned m_callLinkInfoIndex;
+
+#if USE(JSVALUE32_64)
+        unsigned m_jumpTargetIndex;
+        unsigned m_mappedBytecodeOffset;
+        int m_mappedVirtualRegisterIndex;
+        RegisterID m_mappedTag;
+        RegisterID m_mappedPayload;
+#else
+        int m_lastResultBytecodeRegister;
+#endif
+        unsigned m_jumpTargetsPosition;
+
+#ifndef NDEBUG
+#if defined(ASSEMBLER_HAS_CONSTANT_POOL) && ASSEMBLER_HAS_CONSTANT_POOL
+        Label m_uninterruptedInstructionSequenceBegin;
+        int m_uninterruptedConstantSequenceBegin;
+#endif
+#endif
+        WeakRandom m_randomGenerator;
+        static CodeRef stringGetByValStubGenerator(JSGlobalData*);
+
+#if ENABLE(VALUE_PROFILER)
+        bool m_canBeOptimized;
+#endif
+    } JIT_CLASS_ALIGNMENT;
+
+    inline void JIT::emit_op_loop(Instruction* currentInstruction)
+    {
+        emitTimeoutCheck();
+        emit_op_jmp(currentInstruction);
+    }
+
+    inline void JIT::emit_op_loop_hint(Instruction*)
+    {
+        emitOptimizationCheck(LoopOptimizationCheck);
+    }
+
+    inline void JIT::emit_op_loop_if_true(Instruction* currentInstruction)
+    {
+        emitTimeoutCheck();
+        emit_op_jtrue(currentInstruction);
+    }
+
+    inline void JIT::emitSlow_op_loop_if_true(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+    {
+        emitSlow_op_jtrue(currentInstruction, iter);
+    }
+
+    inline void JIT::emit_op_loop_if_false(Instruction* currentInstruction)
+    {
+        emitTimeoutCheck();
+        emit_op_jfalse(currentInstruction);
+    }
+
+    inline void JIT::emitSlow_op_loop_if_false(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+    {
+        emitSlow_op_jfalse(currentInstruction, iter);
+    }
+
+    inline void JIT::emit_op_loop_if_less(Instruction* currentInstruction)
+    {
+        emitTimeoutCheck();
+        emit_op_jless(currentInstruction);
+    }
+
+    inline void JIT::emitSlow_op_loop_if_less(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+    {
+        emitSlow_op_jless(currentInstruction, iter);
+    }
+
+    inline void JIT::emit_op_loop_if_lesseq(Instruction* currentInstruction)
+    {
+        emitTimeoutCheck();
+        emit_op_jlesseq(currentInstruction);
+    }
+
+    inline void JIT::emitSlow_op_loop_if_lesseq(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+    {
+        emitSlow_op_jlesseq(currentInstruction, iter);
+    }
+
+    inline void JIT::emit_op_loop_if_greater(Instruction* currentInstruction)
+    {
+        emitTimeoutCheck();
+        emit_op_jgreater(currentInstruction);
+    }
+
+    inline void JIT::emitSlow_op_loop_if_greater(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+    {
+        emitSlow_op_jgreater(currentInstruction, iter);
+    }
+
+    inline void JIT::emit_op_loop_if_greatereq(Instruction* currentInstruction)
+    {
+        emitTimeoutCheck();
+        emit_op_jgreatereq(currentInstruction);
+    }
+
+    inline void JIT::emitSlow_op_loop_if_greatereq(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
+    {
+        emitSlow_op_jgreatereq(currentInstruction, iter);
+    }
+
+} // namespace JSC
+
+#endif // ENABLE(JIT)
+
+#endif // JIT_h