Imported WebKit commit 68645295d2e3e09af2c942f092556f06aa5f8b0d (http://svn.webkit.org/repository/webkit/trunk@128073)

New snapshot

20 files changed, 155 insertions, 161 deletions

diff --git a/Source/JavaScriptCore/jit/ExecutableAllocatorFixedVMPool.cpp b/Source/JavaScriptCore/jit/ExecutableAllocatorFixedVMPool.cpp
index ad3343d11..7a53b8e2e 100644
--- a/Source/JavaScriptCore/jit/ExecutableAllocatorFixedVMPool.cpp
+++ b/Source/JavaScriptCore/jit/ExecutableAllocatorFixedVMPool.cpp
@@ -48,6 +48,7 @@ namespace JSC {
 uintptr_t startOfFixedExecutableMemoryPool;
 
 class FixedVMPoolExecutableAllocator : public MetaAllocator {
+    WTF_MAKE_FAST_ALLOCATED;
 public:
     FixedVMPoolExecutableAllocator()
         : MetaAllocator(jitAllocationGranule) // round up all allocations to 32 bytes
diff --git a/Source/JavaScriptCore/jit/GCAwareJITStubRoutine.cpp b/Source/JavaScriptCore/jit/GCAwareJITStubRoutine.cpp
index 7ea61178c..0f0eb14b7 100644
--- a/Source/JavaScriptCore/jit/GCAwareJITStubRoutine.cpp
+++ b/Source/JavaScriptCore/jit/GCAwareJITStubRoutine.cpp
@@ -30,7 +30,7 @@
 
 #include "Heap.h"
 #include "JSGlobalData.h"
-#include "ScopeChain.h"
+
 #include "SlotVisitor.h"
 #include "Structure.h"
 
diff --git a/Source/JavaScriptCore/jit/HostCallReturnValue.cpp b/Source/JavaScriptCore/jit/HostCallReturnValue.cpp
index 9d449c374..c4d2e6ad9 100644
--- a/Source/JavaScriptCore/jit/HostCallReturnValue.cpp
+++ b/Source/JavaScriptCore/jit/HostCallReturnValue.cpp
@@ -30,7 +30,7 @@
 #include <wtf/InlineASM.h>
 #include "JSObject.h"
 #include "JSValueInlineMethods.h"
-#include "ScopeChain.h"
+
 
 namespace JSC {
 
diff --git a/Source/JavaScriptCore/jit/HostCallReturnValue.h b/Source/JavaScriptCore/jit/HostCallReturnValue.h
index b134c73da..0e17ca035 100644
--- a/Source/JavaScriptCore/jit/HostCallReturnValue.h
+++ b/Source/JavaScriptCore/jit/HostCallReturnValue.h
@@ -33,7 +33,7 @@
 // Unfortunately this only works on GCC-like compilers. And it's currently only used
 // by LLInt and DFG, which also are restricted to GCC-like compilers. We should
 // probably fix that at some point.
-#if COMPILER(GCC)
+#if COMPILER(GCC) && ENABLE(JIT)
 
 #if CALLING_CONVENTION_IS_STDCALL
 #define HOST_CALL_RETURN_VALUE_OPTION CDECL
diff --git a/Source/JavaScriptCore/jit/JIT.cpp b/Source/JavaScriptCore/jit/JIT.cpp
index 52a7158e6..6083a66e4 100644
--- a/Source/JavaScriptCore/jit/JIT.cpp
+++ b/Source/JavaScriptCore/jit/JIT.cpp
@@ -318,8 +318,8 @@ void JIT::privateCompileMainPass()
         DEFINE_OP(op_pre_inc)
         DEFINE_OP(op_profile_did_call)
         DEFINE_OP(op_profile_will_call)
-        DEFINE_OP(op_push_new_scope)
-        DEFINE_OP(op_push_scope)
+        DEFINE_OP(op_push_name_scope)
+        DEFINE_OP(op_push_with_scope)
         case op_put_by_id_out_of_line:
         case op_put_by_id_transition_direct:
         case op_put_by_id_transition_normal:
diff --git a/Source/JavaScriptCore/jit/JIT.h b/Source/JavaScriptCore/jit/JIT.h
index 5529551d6..beb4cc060 100644
--- a/Source/JavaScriptCore/jit/JIT.h
+++ b/Source/JavaScriptCore/jit/JIT.h
@@ -60,7 +60,7 @@ namespace JSC {
     class Interpreter;
     class Register;
     class RegisterFile;
-    class ScopeChainNode;
+    class JSScope;
     class StructureChain;
 
     struct CallLinkInfo;
@@ -671,8 +671,8 @@ namespace JSC {
         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_push_name_scope(Instruction*);
+        void emit_op_push_with_scope(Instruction*);
         void emit_op_put_by_id(Instruction*);
         void emit_op_put_by_index(Instruction*);
         void emit_op_put_by_val(Instruction*);
diff --git a/Source/JavaScriptCore/jit/JITCall.cpp b/Source/JavaScriptCore/jit/JITCall.cpp
index 7664eb746..f6ea71e17 100644
--- a/Source/JavaScriptCore/jit/JITCall.cpp
+++ b/Source/JavaScriptCore/jit/JITCall.cpp
@@ -160,6 +160,14 @@ void JIT::compileOpCall(OpcodeID opcodeID, Instruction* instruction, unsigned ca
         int argCount = instruction[2].u.operand;
         int registerOffset = instruction[3].u.operand;
 
+        if (opcodeID == op_call && canBeOptimized()) {
+            emitGetVirtualRegister(registerOffset + CallFrame::argumentOffsetIncludingThis(0), regT0);
+            Jump done = emitJumpIfNotJSCell(regT0);
+            loadPtr(Address(regT0, JSCell::structureOffset()), regT0);
+            storePtr(regT0, instruction[5].u.arrayProfile->addressOfLastSeenStructure());
+            done.link(this);
+        }
+    
         addPtr(TrustedImm32(registerOffset * sizeof(Register)), callFrameRegister, regT1);
         store32(TrustedImm32(argCount), Address(regT1, RegisterFile::ArgumentCount * static_cast<int>(sizeof(Register)) + OBJECT_OFFSETOF(EncodedValueDescriptor, asBits.payload)));
     } // regT1 holds newCallFrame with ArgumentCount initialized.
@@ -188,7 +196,7 @@ void JIT::compileOpCall(OpcodeID opcodeID, Instruction* instruction, unsigned ca
     m_callStructureStubCompilationInfo[callLinkInfoIndex].callType = CallLinkInfo::callTypeFor(opcodeID);
     m_callStructureStubCompilationInfo[callLinkInfoIndex].bytecodeIndex = m_bytecodeOffset;
 
-    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scopeChain)), regT1);
+    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scope)), regT1);
     emitPutToCallFrameHeader(regT1, RegisterFile::ScopeChain);
     m_callStructureStubCompilationInfo[callLinkInfoIndex].hotPathOther = emitNakedCall();
 
diff --git a/Source/JavaScriptCore/jit/JITCall32_64.cpp b/Source/JavaScriptCore/jit/JITCall32_64.cpp
index 7d86e615f..6195d0bb9 100644
--- a/Source/JavaScriptCore/jit/JITCall32_64.cpp
+++ b/Source/JavaScriptCore/jit/JITCall32_64.cpp
@@ -236,7 +236,15 @@ void JIT::compileOpCall(OpcodeID opcodeID, Instruction* instruction, unsigned ca
     else {
         int argCount = instruction[2].u.operand;
         int registerOffset = instruction[3].u.operand;
-
+        
+        if (opcodeID == op_call && canBeOptimized()) {
+            emitLoad(registerOffset + CallFrame::argumentOffsetIncludingThis(0), regT0, regT1);
+            Jump done = branch32(NotEqual, regT0, TrustedImm32(JSValue::CellTag));
+            loadPtr(Address(regT1, JSCell::structureOffset()), regT1);
+            storePtr(regT1, instruction[5].u.arrayProfile->addressOfLastSeenStructure());
+            done.link(this);
+        }
+    
         addPtr(TrustedImm32(registerOffset * sizeof(Register)), callFrameRegister, regT3);
 
         store32(TrustedImm32(argCount), payloadFor(RegisterFile::ArgumentCount, regT3));
@@ -268,7 +276,7 @@ void JIT::compileOpCall(OpcodeID opcodeID, Instruction* instruction, unsigned ca
     m_callStructureStubCompilationInfo[callLinkInfoIndex].callType = CallLinkInfo::callTypeFor(opcodeID);
     m_callStructureStubCompilationInfo[callLinkInfoIndex].bytecodeIndex = m_bytecodeOffset;
 
-    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scopeChain)), regT1);
+    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scope)), regT1);
     emitPutCellToCallFrameHeader(regT1, RegisterFile::ScopeChain);
     m_callStructureStubCompilationInfo[callLinkInfoIndex].hotPathOther = emitNakedCall();
 
diff --git a/Source/JavaScriptCore/jit/JITCode.h b/Source/JavaScriptCore/jit/JITCode.h
index 478fcc7bf..e39b4f98d 100644
--- a/Source/JavaScriptCore/jit/JITCode.h
+++ b/Source/JavaScriptCore/jit/JITCode.h
@@ -26,7 +26,7 @@
 #ifndef JITCode_h
 #define JITCode_h
 
-#if ENABLE(JIT)
+#if ENABLE(JIT) || ENABLE(LLINT)
 #include "CallFrame.h"
 #include "JSValue.h"
 #include "Disassembler.h"
@@ -42,7 +42,7 @@ namespace JSC {
 #endif
     
     class JITCode {
-#if ENABLE(JIT)
+#if ENABLE(JIT) || ENABLE(LLINT)
         typedef MacroAssemblerCodeRef CodeRef;
         typedef MacroAssemblerCodePtr CodePtr;
 #else
@@ -77,7 +77,7 @@ namespace JSC {
             return jitType == InterpreterThunk || jitType == BaselineJIT;
         }
         
-#if ENABLE(JIT)
+#if ENABLE(JIT) || ENABLE(LLINT)
         JITCode()
             : m_jitType(None)
         {
@@ -127,12 +127,14 @@ namespace JSC {
             return static_cast<unsigned>(result);
         }
 
+#if ENABLE(JIT)
         // Execute the code!
         inline JSValue execute(RegisterFile* registerFile, CallFrame* callFrame, JSGlobalData* globalData)
         {
             JSValue result = JSValue::decode(ctiTrampoline(m_ref.code().executableAddress(), registerFile, callFrame, 0, 0, globalData));
             return globalData->exception ? jsNull() : result;
         }
+#endif
 
         void* start() const
         {
@@ -182,7 +184,7 @@ namespace JSC {
 
         CodeRef m_ref;
         JITType m_jitType;
-#endif // ENABLE(JIT)
+#endif // ENABLE(JIT) || ENABLE(LLINT)
     };
 
 };
diff --git a/Source/JavaScriptCore/jit/JITDriver.h b/Source/JavaScriptCore/jit/JITDriver.h
index 7b5cc28eb..318b4e7aa 100644
--- a/Source/JavaScriptCore/jit/JITDriver.h
+++ b/Source/JavaScriptCore/jit/JITDriver.h
@@ -75,7 +75,7 @@ inline bool jitCompileIfAppropriate(ExecState* exec, OwnPtr<CodeBlockType>& code
     return true;
 }
 
-inline bool jitCompileFunctionIfAppropriate(ExecState* exec, OwnPtr<FunctionCodeBlock>& codeBlock, JITCode& jitCode, MacroAssemblerCodePtr& jitCodeWithArityCheck, SharedSymbolTable*& symbolTable, JITCode::JITType jitType, unsigned bytecodeIndex, JITCompilationEffort effort)
+inline bool jitCompileFunctionIfAppropriate(ExecState* exec, OwnPtr<FunctionCodeBlock>& codeBlock, JITCode& jitCode, MacroAssemblerCodePtr& jitCodeWithArityCheck, WriteBarrier<SharedSymbolTable>& symbolTable, JITCode::JITType jitType, unsigned bytecodeIndex, JITCompilationEffort effort)
 {
     JSGlobalData& globalData = exec->globalData();
     
@@ -99,7 +99,7 @@ inline bool jitCompileFunctionIfAppropriate(ExecState* exec, OwnPtr<FunctionCode
     } else {
         if (codeBlock->alternative()) {
             codeBlock = static_pointer_cast<FunctionCodeBlock>(codeBlock->releaseAlternative());
-            symbolTable = codeBlock->sharedSymbolTable();
+            symbolTable.set(exec->globalData(), codeBlock->ownerExecutable(), codeBlock->symbolTable());
             jitCode = oldJITCode;
             jitCodeWithArityCheck = oldJITCodeWithArityCheck;
             return false;
diff --git a/Source/JavaScriptCore/jit/JITExceptions.cpp b/Source/JavaScriptCore/jit/JITExceptions.cpp
index 2955fac8d..f6cec24bd 100644
--- a/Source/JavaScriptCore/jit/JITExceptions.cpp
+++ b/Source/JavaScriptCore/jit/JITExceptions.cpp
@@ -32,7 +32,7 @@
 #include "JSGlobalData.h"
 #include "JSValue.h"
 
-#if ENABLE(JIT)
+#if ENABLE(JIT) || ENABLE(LLINT)
 
 namespace JSC {
 
@@ -47,10 +47,10 @@ ExceptionHandler genericThrow(JSGlobalData* globalData, ExecState* callFrame, JS
     void* catchRoutine;
     Instruction* catchPCForInterpreter = 0;
     if (handler) {
-        catchRoutine = handler->nativeCode.executableAddress();
         catchPCForInterpreter = &callFrame->codeBlock()->instructions()[handler->target];
+        catchRoutine = ExecutableBase::catchRoutineFor(handler, catchPCForInterpreter);
     } else
-        catchRoutine = FunctionPtr(ctiOpThrowNotCaught).value();
+        catchRoutine = FunctionPtr(LLInt::getCodePtr(ctiOpThrowNotCaught)).value();
     
     globalData->callFrameForThrow = callFrame;
     globalData->targetMachinePCForThrow = catchRoutine;
diff --git a/Source/JavaScriptCore/jit/JITExceptions.h b/Source/JavaScriptCore/jit/JITExceptions.h
index 59ded187d..1555f95dc 100644
--- a/Source/JavaScriptCore/jit/JITExceptions.h
+++ b/Source/JavaScriptCore/jit/JITExceptions.h
@@ -29,7 +29,7 @@
 #include "JSValue.h"
 #include "MacroAssemblerCodeRef.h"
 
-#if ENABLE(ASSEMBLER)
+#if ENABLE(JIT) || ENABLE(LLINT)
 
 namespace JSC {
 
@@ -50,7 +50,7 @@ ExceptionHandler jitThrow(JSGlobalData*, ExecState*, JSValue exceptionValue, Ret
 
 } // namespace JSC
 
-#endif
+#endif // ENABLE(JIT) || ENABLE(LLINT)
 
 #endif // JITExceptions_h
 
diff --git a/Source/JavaScriptCore/jit/JITOpcodes.cpp b/Source/JavaScriptCore/jit/JITOpcodes.cpp
index 8ebad61ff..9b7dc634f 100644
--- a/Source/JavaScriptCore/jit/JITOpcodes.cpp
+++ b/Source/JavaScriptCore/jit/JITOpcodes.cpp
@@ -75,7 +75,7 @@ PassRefPtr<ExecutableMemoryHandle> JIT::privateCompileCTIMachineTrampolines(JSGl
     callSlowCase.append(emitJumpIfNotType(regT0, regT1, JSFunctionType));
 
     // Finish canonical initialization before JS function call.
-    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scopeChain)), regT1);
+    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scope)), regT1);
     emitPutCellToCallFrameHeader(regT1, RegisterFile::ScopeChain);
 
     // Also initialize ReturnPC for use by lazy linking and exceptions.
@@ -95,7 +95,7 @@ PassRefPtr<ExecutableMemoryHandle> JIT::privateCompileCTIMachineTrampolines(JSGl
     constructSlowCase.append(emitJumpIfNotType(regT0, regT1, JSFunctionType));
 
     // Finish canonical initialization before JS function call.
-    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scopeChain)), regT1);
+    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scope)), regT1);
     emitPutCellToCallFrameHeader(regT1, RegisterFile::ScopeChain);
 
     // Also initialize ReturnPC for use by lazy linking and exeptions.
@@ -115,7 +115,7 @@ PassRefPtr<ExecutableMemoryHandle> JIT::privateCompileCTIMachineTrampolines(JSGl
     callSlowCase.append(emitJumpIfNotType(regT0, regT1, JSFunctionType));
 
     // Finish canonical initialization before JS function call.
-    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scopeChain)), regT1);
+    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scope)), regT1);
     emitPutCellToCallFrameHeader(regT1, RegisterFile::ScopeChain);
 
     loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_executable)), regT2);
@@ -138,7 +138,7 @@ PassRefPtr<ExecutableMemoryHandle> JIT::privateCompileCTIMachineTrampolines(JSGl
     constructSlowCase.append(emitJumpIfNotType(regT0, regT1, JSFunctionType));
 
     // Finish canonical initialization before JS function call.
-    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scopeChain)), regT1);
+    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scope)), regT1);
     emitPutCellToCallFrameHeader(regT1, RegisterFile::ScopeChain);
 
     loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_executable)), regT2);
@@ -1003,11 +1003,11 @@ void JIT::emit_op_next_pname(Instruction* currentInstruction)
     end.link(this);
 }
 
-void JIT::emit_op_push_scope(Instruction* currentInstruction)
+void JIT::emit_op_push_with_scope(Instruction* currentInstruction)
 {
-    JITStubCall stubCall(this, cti_op_push_scope);
+    JITStubCall stubCall(this, cti_op_push_with_scope);
     stubCall.addArgument(currentInstruction[1].u.operand, regT2);
-    stubCall.call(currentInstruction[1].u.operand);
+    stubCall.call();
 }
 
 void JIT::emit_op_pop_scope(Instruction*)
@@ -1072,12 +1072,13 @@ void JIT::emit_op_to_jsnumber(Instruction* currentInstruction)
     emitPutVirtualRegister(currentInstruction[1].u.operand);
 }
 
-void JIT::emit_op_push_new_scope(Instruction* currentInstruction)
+void JIT::emit_op_push_name_scope(Instruction* currentInstruction)
 {
-    JITStubCall stubCall(this, cti_op_push_new_scope);
-    stubCall.addArgument(TrustedImmPtr(&m_codeBlock->identifier(currentInstruction[2].u.operand)));
-    stubCall.addArgument(currentInstruction[3].u.operand, regT2);
-    stubCall.call(currentInstruction[1].u.operand);
+    JITStubCall stubCall(this, cti_op_push_name_scope);
+    stubCall.addArgument(TrustedImmPtr(&m_codeBlock->identifier(currentInstruction[1].u.operand)));
+    stubCall.addArgument(currentInstruction[2].u.operand, regT2);
+    stubCall.addArgument(TrustedImm32(currentInstruction[3].u.operand));
+    stubCall.call();
 }
 
 void JIT::emit_op_catch(Instruction* currentInstruction)
@@ -1331,7 +1332,7 @@ void JIT::emit_op_profile_did_call(Instruction* currentInstruction)
 
 void JIT::emitSlow_op_convert_this(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
-    void* globalThis = m_codeBlock->globalObject()->globalScopeChain()->globalThis.get();
+    void* globalThis = m_codeBlock->globalObject()->globalThis();
 
     linkSlowCase(iter);
     if (shouldEmitProfiling())
@@ -1591,15 +1592,13 @@ void JIT::emit_op_resolve_global_dynamic(Instruction* currentInstruction)
         Jump activationNotCreated;
         if (checkTopLevel)
             activationNotCreated = branchTestPtr(Zero, addressFor(m_codeBlock->activationRegister()));
-        loadPtr(Address(regT0, OBJECT_OFFSETOF(ScopeChainNode, object)), regT1);
-        addSlowCase(checkStructure(regT1, m_globalData->activationStructure.get()));
-        loadPtr(Address(regT0, OBJECT_OFFSETOF(ScopeChainNode, next)), regT0);
+        addSlowCase(checkStructure(regT0, m_codeBlock->globalObject()->activationStructure()));
+        loadPtr(Address(regT0, JSScope::offsetOfNext()), regT0);
         activationNotCreated.link(this);
     }
     while (skip--) {
-        loadPtr(Address(regT0, OBJECT_OFFSETOF(ScopeChainNode, object)), regT1);
-        addSlowCase(checkStructure(regT1, m_globalData->activationStructure.get()));
-        loadPtr(Address(regT0, OBJECT_OFFSETOF(ScopeChainNode, next)), regT0);
+        addSlowCase(checkStructure(regT0, m_codeBlock->globalObject()->activationStructure()));
+        loadPtr(Address(regT0, JSScope::offsetOfNext()), regT0);
     }
     emit_op_resolve_global(currentInstruction, true);
 }
diff --git a/Source/JavaScriptCore/jit/JITOpcodes32_64.cpp b/Source/JavaScriptCore/jit/JITOpcodes32_64.cpp
index 00c886eb7..c94f5d910 100644
--- a/Source/JavaScriptCore/jit/JITOpcodes32_64.cpp
+++ b/Source/JavaScriptCore/jit/JITOpcodes32_64.cpp
@@ -69,7 +69,7 @@ PassRefPtr<ExecutableMemoryHandle> JIT::privateCompileCTIMachineTrampolines(JSGl
     callSlowCase.append(emitJumpIfNotType(regT0, regT1, JSFunctionType));
 
     // Finish canonical initialization before JS function call.
-    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scopeChain)), regT1);
+    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scope)), regT1);
     emitPutCellToCallFrameHeader(regT1, RegisterFile::ScopeChain);
 
     // Also initialize ReturnPC for use by lazy linking and exceptions.
@@ -89,7 +89,7 @@ PassRefPtr<ExecutableMemoryHandle> JIT::privateCompileCTIMachineTrampolines(JSGl
     constructSlowCase.append(emitJumpIfNotType(regT0, regT1, JSFunctionType));
 
     // Finish canonical initialization before JS function call.
-    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scopeChain)), regT1);
+    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scope)), regT1);
     emitPutCellToCallFrameHeader(regT1, RegisterFile::ScopeChain);
 
     // Also initialize ReturnPC for use by lazy linking and exeptions.
@@ -109,7 +109,7 @@ PassRefPtr<ExecutableMemoryHandle> JIT::privateCompileCTIMachineTrampolines(JSGl
     callSlowCase.append(emitJumpIfNotType(regT0, regT1, JSFunctionType));
 
     // Finish canonical initialization before JS function call.
-    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scopeChain)), regT1);
+    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scope)), regT1);
     emitPutCellToCallFrameHeader(regT1, RegisterFile::ScopeChain);
 
     loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_executable)), regT2);
@@ -133,7 +133,7 @@ PassRefPtr<ExecutableMemoryHandle> JIT::privateCompileCTIMachineTrampolines(JSGl
     constructSlowCase.append(emitJumpIfNotType(regT0, regT1, JSFunctionType));
 
     // Finish canonical initialization before JS function call.
-    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scopeChain)), regT1);
+    loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_scope)), regT1);
     emitPutCellToCallFrameHeader(regT1, RegisterFile::ScopeChain);
 
     loadPtr(Address(regT0, OBJECT_OFFSETOF(JSFunction, m_executable)), regT2);
@@ -1358,11 +1358,11 @@ void JIT::emit_op_next_pname(Instruction* currentInstruction)
     end.link(this);
 }
 
-void JIT::emit_op_push_scope(Instruction* currentInstruction)
+void JIT::emit_op_push_with_scope(Instruction* currentInstruction)
 {
-    JITStubCall stubCall(this, cti_op_push_scope);
+    JITStubCall stubCall(this, cti_op_push_with_scope);
     stubCall.addArgument(currentInstruction[1].u.operand);
-    stubCall.call(currentInstruction[1].u.operand);
+    stubCall.call();
 }
 
 void JIT::emit_op_pop_scope(Instruction*)
@@ -1397,12 +1397,13 @@ void JIT::emitSlow_op_to_jsnumber(Instruction* currentInstruction, Vector<SlowCa
     stubCall.call(dst);
 }
 
-void JIT::emit_op_push_new_scope(Instruction* currentInstruction)
+void JIT::emit_op_push_name_scope(Instruction* currentInstruction)
 {
-    JITStubCall stubCall(this, cti_op_push_new_scope);
-    stubCall.addArgument(TrustedImmPtr(&m_codeBlock->identifier(currentInstruction[2].u.operand)));
-    stubCall.addArgument(currentInstruction[3].u.operand);
-    stubCall.call(currentInstruction[1].u.operand);
+    JITStubCall stubCall(this, cti_op_push_name_scope);
+    stubCall.addArgument(TrustedImmPtr(&m_codeBlock->identifier(currentInstruction[1].u.operand)));
+    stubCall.addArgument(currentInstruction[2].u.operand);
+    stubCall.addArgument(TrustedImm32(currentInstruction[3].u.operand));
+    stubCall.call();
 }
 
 void JIT::emit_op_catch(Instruction* currentInstruction)
@@ -1586,7 +1587,7 @@ void JIT::emit_op_convert_this(Instruction* currentInstruction)
 
 void JIT::emitSlow_op_convert_this(Instruction* currentInstruction, Vector<SlowCaseEntry>::iterator& iter)
 {
-    void* globalThis = m_codeBlock->globalObject()->globalScopeChain()->globalThis.get();
+    void* globalThis = m_codeBlock->globalObject()->globalThis();
     unsigned thisRegister = currentInstruction[1].u.operand;
 
     linkSlowCase(iter);
diff --git a/Source/JavaScriptCore/jit/JITPropertyAccess.cpp b/Source/JavaScriptCore/jit/JITPropertyAccess.cpp
index 16af9125b..ada862a53 100644
--- a/Source/JavaScriptCore/jit/JITPropertyAccess.cpp
+++ b/Source/JavaScriptCore/jit/JITPropertyAccess.cpp
@@ -493,6 +493,7 @@ void JIT::emitSlow_op_put_by_id(Instruction* currentInstruction, Vector<SlowCase
     stubCall.addArgument(regT0);
     stubCall.addArgument(TrustedImmPtr(ident));
     stubCall.addArgument(regT1);
+    move(regT0, nonArgGPR1);
     Call call = stubCall.call();
 
     // Track the location of the call; this will be used to recover patch information.
@@ -537,6 +538,8 @@ void JIT::compileGetDirectOffset(JSObject* base, RegisterID result, PropertyOffs
 
 void JIT::privateCompilePutByIdTransition(StructureStubInfo* stubInfo, Structure* oldStructure, Structure* newStructure, PropertyOffset cachedOffset, StructureChain* chain, ReturnAddressPtr returnAddress, bool direct)
 {
+    move(nonArgGPR1, regT0);
+
     JumpList failureCases;
     // Check eax is an object of the right Structure.
     failureCases.append(emitJumpIfNotJSCell(regT0));
@@ -1067,13 +1070,12 @@ void JIT::emit_op_get_scoped_var(Instruction* currentInstruction)
         Jump activationNotCreated;
         if (checkTopLevel)
             activationNotCreated = branchTestPtr(Zero, addressFor(m_codeBlock->activationRegister()));
-        loadPtr(Address(regT0, OBJECT_OFFSETOF(ScopeChainNode, next)), regT0);
+        loadPtr(Address(regT0, JSScope::offsetOfNext()), regT0);
         activationNotCreated.link(this);
     }
     while (skip--)
-        loadPtr(Address(regT0, OBJECT_OFFSETOF(ScopeChainNode, next)), regT0);
+        loadPtr(Address(regT0, JSScope::offsetOfNext()), regT0);
 
-    loadPtr(Address(regT0, OBJECT_OFFSETOF(ScopeChainNode, object)), regT0);
     loadPtr(Address(regT0, JSVariableObject::offsetOfRegisters()), regT0);
     loadPtr(Address(regT0, currentInstruction[2].u.operand * sizeof(Register)), regT0);
     emitValueProfilingSite();
@@ -1093,12 +1095,11 @@ void JIT::emit_op_put_scoped_var(Instruction* currentInstruction)
         Jump activationNotCreated;
         if (checkTopLevel)
             activationNotCreated = branchTestPtr(Zero, addressFor(m_codeBlock->activationRegister()));
-        loadPtr(Address(regT1, OBJECT_OFFSETOF(ScopeChainNode, next)), regT1);
+        loadPtr(Address(regT1, JSScope::offsetOfNext()), regT1);
         activationNotCreated.link(this);
     }
     while (skip--)
-        loadPtr(Address(regT1, OBJECT_OFFSETOF(ScopeChainNode, next)), regT1);
-    loadPtr(Address(regT1, OBJECT_OFFSETOF(ScopeChainNode, object)), regT1);
+        loadPtr(Address(regT1, JSScope::offsetOfNext()), regT1);
 
     emitWriteBarrier(regT1, regT0, regT2, regT3, ShouldFilterImmediates, WriteBarrierForVariableAccess);
 
@@ -1162,7 +1163,7 @@ void JIT::resetPatchPutById(RepatchBuffer& repatchBuffer, StructureStubInfo* stu
     else
         repatchBuffer.relink(stubInfo->callReturnLocation, cti_op_put_by_id);
     repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelPtrAtOffset(stubInfo->patch.baseline.u.put.structureToCompare), reinterpret_cast<void*>(-1));
-    repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabelCompactAtOffset(stubInfo->patch.baseline.u.put.displacementLabel), 0);
+    repatchBuffer.repatch(stubInfo->hotPathBegin.dataLabel32AtOffset(stubInfo->patch.baseline.u.put.displacementLabel), 0);
 }
 
 #endif // USE(JSVALUE64)
diff --git a/Source/JavaScriptCore/jit/JITPropertyAccess32_64.cpp b/Source/JavaScriptCore/jit/JITPropertyAccess32_64.cpp
index 6ef25046f..f3c79a985 100644
--- a/Source/JavaScriptCore/jit/JITPropertyAccess32_64.cpp
+++ b/Source/JavaScriptCore/jit/JITPropertyAccess32_64.cpp
@@ -213,7 +213,7 @@ void JIT::emit_op_get_by_val(Instruction* currentInstruction)
 #if ENABLE(VALUE_PROFILER)
     storePtr(regT1, currentInstruction[4].u.arrayProfile->addressOfLastSeenStructure());
 #endif
-    addSlowCase(branchPtr(NotEqual, Address(regT1, JSCell::classInfoOffset()), TrustedImmPtr(&JSArray::s_info)));
+    addSlowCase(branchPtr(NotEqual, Address(regT1, Structure::classInfoOffset()), TrustedImmPtr(&JSArray::s_info)));
     
     loadPtr(Address(regT0, JSArray::storageOffset()), regT3);
     addSlowCase(branch32(AboveOrEqual, regT2, Address(regT0, JSArray::vectorLengthOffset())));
@@ -1108,13 +1108,12 @@ void JIT::emit_op_get_scoped_var(Instruction* currentInstruction)
         Jump activationNotCreated;
         if (checkTopLevel)
             activationNotCreated = branch32(Equal, tagFor(m_codeBlock->activationRegister()), TrustedImm32(JSValue::EmptyValueTag));
-        loadPtr(Address(regT2, OBJECT_OFFSETOF(ScopeChainNode, next)), regT2);
+        loadPtr(Address(regT2, JSScope::offsetOfNext()), regT2);
         activationNotCreated.link(this);
     }
     while (skip--)
-        loadPtr(Address(regT2, OBJECT_OFFSETOF(ScopeChainNode, next)), regT2);
+        loadPtr(Address(regT2, JSScope::offsetOfNext()), regT2);
 
-    loadPtr(Address(regT2, OBJECT_OFFSETOF(ScopeChainNode, object)), regT2);
     loadPtr(Address(regT2, JSVariableObject::offsetOfRegisters()), regT2);
 
     emitLoad(index, regT1, regT0, regT2);
@@ -1138,12 +1137,11 @@ void JIT::emit_op_put_scoped_var(Instruction* currentInstruction)
         Jump activationNotCreated;
         if (checkTopLevel)
             activationNotCreated = branch32(Equal, tagFor(m_codeBlock->activationRegister()), TrustedImm32(JSValue::EmptyValueTag));
-        loadPtr(Address(regT2, OBJECT_OFFSETOF(ScopeChainNode, next)), regT2);
+        loadPtr(Address(regT2, JSScope::offsetOfNext()), regT2);
         activationNotCreated.link(this);
     }
     while (skip--)
-        loadPtr(Address(regT2, OBJECT_OFFSETOF(ScopeChainNode, next)), regT2);
-    loadPtr(Address(regT2, OBJECT_OFFSETOF(ScopeChainNode, object)), regT2);
+        loadPtr(Address(regT2, JSScope::offsetOfNext()), regT2);
 
     loadPtr(Address(regT2, JSVariableObject::offsetOfRegisters()), regT3);
     emitStore(index, regT1, regT0, regT3);
diff --git a/Source/JavaScriptCore/jit/JITStubRoutine.cpp b/Source/JavaScriptCore/jit/JITStubRoutine.cpp
index 951665318..121836ce9 100644
--- a/Source/JavaScriptCore/jit/JITStubRoutine.cpp
+++ b/Source/JavaScriptCore/jit/JITStubRoutine.cpp
@@ -29,7 +29,7 @@
 #if ENABLE(JIT)
 
 #include "JSObject.h"
-#include "ScopeChain.h"
+
 #include "SlotVisitor.h"
 
 namespace JSC {
diff --git a/Source/JavaScriptCore/jit/JITStubs.cpp b/Source/JavaScriptCore/jit/JITStubs.cpp
index cc899587f..8fc395a63 100644
--- a/Source/JavaScriptCore/jit/JITStubs.cpp
+++ b/Source/JavaScriptCore/jit/JITStubs.cpp
@@ -50,10 +50,11 @@
 #include "JSArray.h"
 #include "JSFunction.h"
 #include "JSGlobalObjectFunctions.h"
+#include "JSNameScope.h"
 #include "JSNotAnObject.h"
 #include "JSPropertyNameIterator.h"
-#include "JSStaticScopeObject.h"
 #include "JSString.h"
+#include "JSWithScope.h"
 #include "NameInstance.h"
 #include "ObjectPrototype.h"
 #include "Operations.h"
@@ -203,8 +204,6 @@ SYMBOL_STRING(ctiOpThrowNotCaught) ":" "\n"
 #define PRESERVED_R10_OFFSET             0x58
 #define PRESERVED_R11_OFFSET             0x5C
 #define REGISTER_FILE_OFFSET             0x60
-#define CALLFRAME_OFFSET                 0x64
-#define EXCEPTION_OFFSET                 0x64
 #define FIRST_STACK_ARGUMENT             0x68
 
 #elif (COMPILER(GCC) || COMPILER(MSVC) || COMPILER(RVCT)) && CPU(ARM_TRADITIONAL)
@@ -282,8 +281,6 @@ extern "C" {
 #define PRESERVED_RETURN_ADDRESS_OFFSET 76
 #define THUNK_RETURN_ADDRESS_OFFSET 80
 #define REGISTER_FILE_OFFSET        84
-#define CALLFRAME_OFFSET            88
-#define EXCEPTION_OFFSET            92
 #define GLOBAL_DATA_OFFSET         100
 #define STACK_LENGTH               104
 #elif CPU(SH4)
@@ -462,8 +459,6 @@ SYMBOL_STRING(ctiTrampoline) ":" "\n"
     "li    $17,512      # set timeoutCheckRegister" "\n"
     "move  $25,$4       # move executableAddress to t9" "\n"
     "sw    $5," STRINGIZE_VALUE_OF(REGISTER_FILE_OFFSET) "($29) # store registerFile to current stack" "\n"
-    "sw    $6," STRINGIZE_VALUE_OF(CALLFRAME_OFFSET) "($29)     # store callFrame to curent stack" "\n"
-    "sw    $7," STRINGIZE_VALUE_OF(EXCEPTION_OFFSET) "($29)     # store exception to current stack" "\n"
     "lw    $9," STRINGIZE_VALUE_OF(STACK_LENGTH + 20) "($29)    # load globalData from previous stack" "\n"
     "jalr  $25" "\n"
     "sw    $9," STRINGIZE_VALUE_OF(GLOBAL_DATA_OFFSET) "($29)   # store globalData to current stack" "\n"
@@ -551,8 +546,6 @@ SYMBOL_STRING(ctiTrampoline) ":" "\n"
     "str r10, [sp, #" STRINGIZE_VALUE_OF(PRESERVED_R10_OFFSET) "]" "\n"
     "str r11, [sp, #" STRINGIZE_VALUE_OF(PRESERVED_R11_OFFSET) "]" "\n"
     "str r1, [sp, #" STRINGIZE_VALUE_OF(REGISTER_FILE_OFFSET) "]" "\n"
-    "str r2, [sp, #" STRINGIZE_VALUE_OF(CALLFRAME_OFFSET) "]" "\n"
-    "str r3, [sp, #" STRINGIZE_VALUE_OF(EXCEPTION_OFFSET) "]" "\n"
     "mov r5, r2" "\n"
     "mov r6, #512" "\n"
     "blx r0" "\n"
@@ -680,8 +673,6 @@ __asm EncodedJSValue ctiTrampoline(void*, RegisterFile*, CallFrame*, void* /*unu
     str r10, [sp, # PRESERVED_R10_OFFSET ]
     str r11, [sp, # PRESERVED_R11_OFFSET ]
     str r1, [sp, # REGISTER_FILE_OFFSET ]
-    str r2, [sp, # CALLFRAME_OFFSET ]
-    str r3, [sp, # EXCEPTION_OFFSET ]
     mov r5, r2
     mov r6, #512
     blx r0
@@ -806,7 +797,6 @@ JITThunks::JITThunks(JSGlobalData* globalData)
     ASSERT(OBJECT_OFFSETOF(struct JITStackFrame, preservedR11) == PRESERVED_R11_OFFSET);
 
     ASSERT(OBJECT_OFFSETOF(struct JITStackFrame, registerFile) == REGISTER_FILE_OFFSET);
-    ASSERT(OBJECT_OFFSETOF(struct JITStackFrame, callFrame) == CALLFRAME_OFFSET);
     // The fifth argument is the first item already on the stack.
     ASSERT(OBJECT_OFFSETOF(struct JITStackFrame, unused1) == FIRST_STACK_ARGUMENT);
 
@@ -826,8 +816,6 @@ JITThunks::JITThunks(JSGlobalData* globalData)
     ASSERT(OBJECT_OFFSETOF(struct JITStackFrame, preservedReturnAddress) == PRESERVED_RETURN_ADDRESS_OFFSET);
     ASSERT(OBJECT_OFFSETOF(struct JITStackFrame, thunkReturnAddress) == THUNK_RETURN_ADDRESS_OFFSET);
     ASSERT(OBJECT_OFFSETOF(struct JITStackFrame, registerFile) == REGISTER_FILE_OFFSET);
-    ASSERT(OBJECT_OFFSETOF(struct JITStackFrame, callFrame) == CALLFRAME_OFFSET);
-    ASSERT(OBJECT_OFFSETOF(struct JITStackFrame, unused1) == EXCEPTION_OFFSET);
     ASSERT(OBJECT_OFFSETOF(struct JITStackFrame, globalData) == GLOBAL_DATA_OFFSET);
 
 #endif
@@ -879,7 +867,7 @@ NEVER_INLINE void JITThunks::tryCachePutByID(CallFrame* callFrame, CodeBlock* co
         StructureChain* prototypeChain = structure->prototypeChain(callFrame);
         ASSERT(structure->previousID()->transitionWatchpointSetHasBeenInvalidated());
         stubInfo->initPutByIdTransition(callFrame->globalData(), codeBlock->ownerExecutable(), structure->previousID(), structure, prototypeChain, direct);
-        JIT::compilePutByIdTransition(callFrame->scopeChain()->globalData, codeBlock, stubInfo, structure->previousID(), structure, slot.cachedOffset(), prototypeChain, returnAddress, direct);
+        JIT::compilePutByIdTransition(callFrame->scope()->globalData(), codeBlock, stubInfo, structure->previousID(), structure, slot.cachedOffset(), prototypeChain, returnAddress, direct);
         return;
     }
     
@@ -902,7 +890,7 @@ NEVER_INLINE void JITThunks::tryCacheGetByID(CallFrame* callFrame, CodeBlock* co
     JSGlobalData* globalData = &callFrame->globalData();
 
     if (isJSArray(baseValue) && propertyName == callFrame->propertyNames().length) {
-        JIT::compilePatchGetArrayLength(callFrame->scopeChain()->globalData, codeBlock, returnAddress);
+        JIT::compilePatchGetArrayLength(callFrame->scope()->globalData(), codeBlock, returnAddress);
         return;
     }
     
@@ -962,7 +950,7 @@ NEVER_INLINE void JITThunks::tryCacheGetByID(CallFrame* callFrame, CodeBlock* co
 
         ASSERT(!structure->isDictionary());
         ASSERT(!slotBaseObject->structure()->isDictionary());
-        JIT::compileGetByIdProto(callFrame->scopeChain()->globalData, callFrame, codeBlock, stubInfo, structure, slotBaseObject->structure(), propertyName, slot, offset, returnAddress);
+        JIT::compileGetByIdProto(callFrame->scope()->globalData(), callFrame, codeBlock, stubInfo, structure, slotBaseObject->structure(), propertyName, slot, offset, returnAddress);
         return;
     }
 
@@ -975,7 +963,7 @@ NEVER_INLINE void JITThunks::tryCacheGetByID(CallFrame* callFrame, CodeBlock* co
 
     StructureChain* prototypeChain = structure->prototypeChain(callFrame);
     stubInfo->initGetByIdChain(callFrame->globalData(), codeBlock->ownerExecutable(), structure, prototypeChain, count, slot.cachedPropertyType() == PropertySlot::Value);
-    JIT::compileGetByIdChain(callFrame->scopeChain()->globalData, callFrame, codeBlock, stubInfo, structure, prototypeChain, count, propertyName, slot, offset, returnAddress);
+    JIT::compileGetByIdChain(callFrame->scope()->globalData(), callFrame, codeBlock, stubInfo, structure, prototypeChain, count, propertyName, slot, offset, returnAddress);
 }
 
 #if !defined(NDEBUG)
@@ -1590,7 +1578,7 @@ DEFINE_STUB_FUNCTION(EncodedJSValue, op_get_by_id_method_check)
         // for now.  For now it performs a check on a special object on the global object only used for this
         // purpose.  The object is in no way exposed, and as such the check will always pass.
         if (slot.slotBase() == baseValue) {
-            JIT::patchMethodCallProto(callFrame->globalData(), codeBlock, methodCallLinkInfo, stubInfo, callee, structure, callFrame->scopeChain()->globalObject->methodCallDummy(), STUB_RETURN_ADDRESS);
+            JIT::patchMethodCallProto(callFrame->globalData(), codeBlock, methodCallLinkInfo, stubInfo, callee, structure, callFrame->scope()->globalObject()->methodCallDummy(), STUB_RETURN_ADDRESS);
             return JSValue::encode(result);
         }
     }
@@ -1690,7 +1678,7 @@ DEFINE_STUB_FUNCTION(EncodedJSValue, op_get_by_id_method_check_update)
     // useful. We could try to nop it out altogether, but that's a little messy, so lets do something simpler
     // for now. For now it performs a check on a special object on the global object only used for this
     // purpose. The object is in no way exposed, and as such the check will always pass.
-    JIT::patchMethodCallProto(callFrame->globalData(), codeBlock, methodCallLinkInfo, stubInfo, callee, structure, callFrame->scopeChain()->globalObject->methodCallDummy(), STUB_RETURN_ADDRESS);
+    JIT::patchMethodCallProto(callFrame->globalData(), codeBlock, methodCallLinkInfo, stubInfo, callee, structure, callFrame->scope()->globalObject()->methodCallDummy(), STUB_RETURN_ADDRESS);
     return JSValue::encode(result);
 }
 
@@ -1760,7 +1748,7 @@ DEFINE_STUB_FUNCTION(EncodedJSValue, op_get_by_id_self_fail)
         }
         if (listIndex < POLYMORPHIC_LIST_CACHE_SIZE) {
             stubInfo->u.getByIdSelfList.listSize++;
-            JIT::compileGetByIdSelfList(callFrame->scopeChain()->globalData, codeBlock, stubInfo, polymorphicStructureList, listIndex, baseValue.asCell()->structure(), ident, slot, slot.cachedOffset());
+            JIT::compileGetByIdSelfList(callFrame->scope()->globalData(), codeBlock, stubInfo, polymorphicStructureList, listIndex, baseValue.asCell()->structure(), ident, slot, slot.cachedOffset());
 
             if (listIndex == (POLYMORPHIC_LIST_CACHE_SIZE - 1))
                 ctiPatchCallByReturnAddress(codeBlock, STUB_RETURN_ADDRESS, FunctionPtr(cti_op_get_by_id_generic));
@@ -1878,7 +1866,7 @@ DEFINE_STUB_FUNCTION(EncodedJSValue, op_get_by_id_proto_list)
         int listIndex;
         PolymorphicAccessStructureList* prototypeStructureList = getPolymorphicAccessStructureListSlot(callFrame->globalData(), codeBlock->ownerExecutable(), stubInfo, listIndex);
         if (listIndex < POLYMORPHIC_LIST_CACHE_SIZE) {
-            JIT::compileGetByIdProtoList(callFrame->scopeChain()->globalData, callFrame, codeBlock, stubInfo, prototypeStructureList, listIndex, structure, slotBaseObject->structure(), propertyName, slot, offset);
+            JIT::compileGetByIdProtoList(callFrame->scope()->globalData(), callFrame, codeBlock, stubInfo, prototypeStructureList, listIndex, structure, slotBaseObject->structure(), propertyName, slot, offset);
 
             if (listIndex == (POLYMORPHIC_LIST_CACHE_SIZE - 1))
                 ctiPatchCallByReturnAddress(codeBlock, STUB_RETURN_ADDRESS, FunctionPtr(cti_op_get_by_id_proto_list_full));
@@ -1890,7 +1878,7 @@ DEFINE_STUB_FUNCTION(EncodedJSValue, op_get_by_id_proto_list)
         
         if (listIndex < POLYMORPHIC_LIST_CACHE_SIZE) {
             StructureChain* protoChain = structure->prototypeChain(callFrame);
-            JIT::compileGetByIdChainList(callFrame->scopeChain()->globalData, callFrame, codeBlock, stubInfo, prototypeStructureList, listIndex, structure, protoChain, count, propertyName, slot, offset);
+            JIT::compileGetByIdChainList(callFrame->scope()->globalData(), callFrame, codeBlock, stubInfo, prototypeStructureList, listIndex, structure, protoChain, count, propertyName, slot, offset);
 
             if (listIndex == (POLYMORPHIC_LIST_CACHE_SIZE - 1))
                 ctiPatchCallByReturnAddress(codeBlock, STUB_RETURN_ADDRESS, FunctionPtr(cti_op_get_by_id_proto_list_full));
@@ -2021,8 +2009,8 @@ DEFINE_STUB_FUNCTION(void, optimize)
             return;
         }
         
-        ScopeChainNode* scopeChain = callFrame->scopeChain();
-        JSObject* error = codeBlock->compileOptimized(callFrame, scopeChain, bytecodeIndex);
+        JSScope* scope = callFrame->scope();
+        JSObject* error = codeBlock->compileOptimized(callFrame, scope, bytecodeIndex);
 #if ENABLE(JIT_VERBOSE_OSR)
         if (error)
             dataLog("WARNING: optimized compilation failed.\n");
@@ -2140,7 +2128,7 @@ DEFINE_STUB_FUNCTION(JSObject*, op_new_func)
     STUB_INIT_STACK_FRAME(stackFrame);
     
     ASSERT(stackFrame.callFrame->codeBlock()->codeType() != FunctionCode || !stackFrame.callFrame->codeBlock()->needsFullScopeChain() || stackFrame.callFrame->uncheckedR(stackFrame.callFrame->codeBlock()->activationRegister()).jsValue());
-    return stackFrame.args[0].function()->make(stackFrame.callFrame, stackFrame.callFrame->scopeChain());
+    return JSFunction::create(stackFrame.callFrame, stackFrame.args[0].function(), stackFrame.callFrame->scope());
 }
 
 inline void* jitCompileFor(CallFrame* callFrame, CodeSpecializationKind kind)
@@ -2148,7 +2136,7 @@ inline void* jitCompileFor(CallFrame* callFrame, CodeSpecializationKind kind)
     JSFunction* function = jsCast<JSFunction*>(callFrame->callee());
     ASSERT(!function->isHostFunction());
     FunctionExecutable* executable = function->jsExecutable();
-    ScopeChainNode* callDataScopeChain = function->scope();
+    JSScope* callDataScopeChain = function->scope();
     JSObject* error = executable->compileFor(callFrame, callDataScopeChain, kind);
     if (!error)
         return function;
@@ -2278,7 +2266,7 @@ DEFINE_STUB_FUNCTION(JSObject*, op_push_activation)
     STUB_INIT_STACK_FRAME(stackFrame);
 
     JSActivation* activation = JSActivation::create(stackFrame.callFrame->globalData(), stackFrame.callFrame, static_cast<FunctionExecutable*>(stackFrame.callFrame->codeBlock()->ownerExecutable()));
-    stackFrame.callFrame->setScopeChain(stackFrame.callFrame->scopeChain()->push(activation));
+    stackFrame.callFrame->setScope(activation);
     return activation;
 }
 
@@ -2393,7 +2381,7 @@ DEFINE_STUB_FUNCTION(EncodedJSValue, op_resolve)
 
     CallFrame* callFrame = stackFrame.callFrame;
 
-    JSValue result = CommonSlowPaths::opResolve(callFrame, stackFrame.args[0].identifier());
+    JSValue result = JSScope::resolve(callFrame, stackFrame.args[0].identifier());
     CHECK_FOR_EXCEPTION_AT_END();
     return JSValue::encode(result);
 }
@@ -2624,18 +2612,16 @@ DEFINE_STUB_FUNCTION(EncodedJSValue, op_resolve_base)
 {
     STUB_INIT_STACK_FRAME(stackFrame);
 
-    return JSValue::encode(JSC::resolveBase(stackFrame.callFrame, stackFrame.args[0].identifier(), stackFrame.callFrame->scopeChain(), false));
+    return JSValue::encode(JSScope::resolveBase(stackFrame.callFrame, stackFrame.args[0].identifier(), false));
 }
 
 DEFINE_STUB_FUNCTION(EncodedJSValue, op_resolve_base_strict_put)
 {
     STUB_INIT_STACK_FRAME(stackFrame);
-    JSValue base = JSC::resolveBase(stackFrame.callFrame, stackFrame.args[0].identifier(), stackFrame.callFrame->scopeChain(), true);
-    if (!base) {
-        stackFrame.globalData->exception = createErrorForInvalidGlobalAssignment(stackFrame.callFrame, stackFrame.args[0].identifier().ustring());
-        VM_THROW_EXCEPTION();
-    }
-    return JSValue::encode(base);
+
+    if (JSValue result = JSScope::resolveBase(stackFrame.callFrame, stackFrame.args[0].identifier(), true))
+        return JSValue::encode(result);
+    VM_THROW_EXCEPTION();
 }
 
 DEFINE_STUB_FUNCTION(EncodedJSValue, op_ensure_property_exists)
@@ -2646,7 +2632,7 @@ DEFINE_STUB_FUNCTION(EncodedJSValue, op_ensure_property_exists)
     PropertySlot slot(object);
     ASSERT(stackFrame.callFrame->codeBlock()->isStrictMode());
     if (!object->getPropertySlot(stackFrame.callFrame, stackFrame.args[1].identifier(), slot)) {
-        stackFrame.globalData->exception = createErrorForInvalidGlobalAssignment(stackFrame.callFrame, stackFrame.args[1].identifier().ustring());
+        stackFrame.globalData->exception = createErrorForInvalidGlobalAssignment(stackFrame.callFrame, stackFrame.args[1].identifier().string());
         VM_THROW_EXCEPTION();
     }
 
@@ -2657,7 +2643,7 @@ DEFINE_STUB_FUNCTION(EncodedJSValue, op_resolve_skip)
 {
     STUB_INIT_STACK_FRAME(stackFrame);
 
-    JSValue result = CommonSlowPaths::opResolveSkip(stackFrame.callFrame, stackFrame.args[0].identifier(), stackFrame.args[1].int32());
+    JSValue result = JSScope::resolveSkip(stackFrame.callFrame, stackFrame.args[0].identifier(), stackFrame.args[1].int32());
     CHECK_FOR_EXCEPTION_AT_END();
     return JSValue::encode(result);
 }
@@ -2667,28 +2653,20 @@ DEFINE_STUB_FUNCTION(EncodedJSValue, op_resolve_global)
     STUB_INIT_STACK_FRAME(stackFrame);
 
     CallFrame* callFrame = stackFrame.callFrame;
-    CodeBlock* codeBlock = callFrame->codeBlock();
-    JSGlobalObject* globalObject = codeBlock->globalObject();
     Identifier& ident = stackFrame.args[0].identifier();
+    CodeBlock* codeBlock = callFrame->codeBlock();
     unsigned globalResolveInfoIndex = stackFrame.args[1].int32();
-    ASSERT(globalObject->isGlobalObject());
-
-    PropertySlot slot(globalObject);
-    if (globalObject->getPropertySlot(callFrame, ident, slot)) {
-        JSValue result = slot.getValue(callFrame, ident);
-        if (slot.isCacheableValue() && !globalObject->structure()->isUncacheableDictionary() && slot.slotBase() == globalObject) {
-            GlobalResolveInfo& globalResolveInfo = codeBlock->globalResolveInfo(globalResolveInfoIndex);
-            globalResolveInfo.structure.set(callFrame->globalData(), codeBlock->ownerExecutable(), globalObject->structure());
-            globalResolveInfo.offset = slot.cachedOffset();
-            return JSValue::encode(result);
-        }
-
-        CHECK_FOR_EXCEPTION_AT_END();
-        return JSValue::encode(result);
-    }
-
-    stackFrame.globalData->exception = createUndefinedVariableError(callFrame, ident);
-    VM_THROW_EXCEPTION();
+    GlobalResolveInfo& globalResolveInfo = codeBlock->globalResolveInfo(globalResolveInfoIndex);
+
+    JSValue result = JSScope::resolveGlobal(
+        callFrame,
+        ident,
+        callFrame->lexicalGlobalObject(),
+        &globalResolveInfo.structure,
+        &globalResolveInfo.offset
+    );
+    CHECK_FOR_EXCEPTION();
+    return JSValue::encode(result);
 }
 
 DEFINE_STUB_FUNCTION(EncodedJSValue, op_div)
@@ -2970,7 +2948,7 @@ DEFINE_STUB_FUNCTION(EncodedJSValue, op_resolve_with_base)
     STUB_INIT_STACK_FRAME(stackFrame);
 
     CallFrame* callFrame = stackFrame.callFrame;
-    JSValue result = CommonSlowPaths::opResolveWithBase(callFrame, stackFrame.args[0].identifier(), callFrame->registers()[stackFrame.args[1].int32()]);
+    JSValue result = JSScope::resolveWithBase(callFrame, stackFrame.args[0].identifier(), &callFrame->registers()[stackFrame.args[1].int32()]);
     CHECK_FOR_EXCEPTION_AT_END();
     return JSValue::encode(result);
 }
@@ -2980,7 +2958,7 @@ DEFINE_STUB_FUNCTION(EncodedJSValue, op_resolve_with_this)
     STUB_INIT_STACK_FRAME(stackFrame);
 
     CallFrame* callFrame = stackFrame.callFrame;
-    JSValue result = CommonSlowPaths::opResolveWithThis(callFrame, stackFrame.args[0].identifier(), callFrame->registers()[stackFrame.args[1].int32()]);
+    JSValue result = JSScope::resolveWithThis(callFrame, stackFrame.args[0].identifier(), &callFrame->registers()[stackFrame.args[1].int32()]);
     CHECK_FOR_EXCEPTION_AT_END();
     return JSValue::encode(result);
 }
@@ -2991,21 +2969,9 @@ DEFINE_STUB_FUNCTION(JSObject*, op_new_func_exp)
     CallFrame* callFrame = stackFrame.callFrame;
 
     FunctionExecutable* function = stackFrame.args[0].function();
-    JSFunction* func = function->make(callFrame, callFrame->scopeChain());
+    JSFunction* func = JSFunction::create(callFrame, function, callFrame->scope());
     ASSERT(callFrame->codeBlock()->codeType() != FunctionCode || !callFrame->codeBlock()->needsFullScopeChain() || callFrame->uncheckedR(callFrame->codeBlock()->activationRegister()).jsValue());
 
-    /* 
-        The Identifier in a FunctionExpression can be referenced from inside
-        the FunctionExpression's FunctionBody to allow the function to call
-        itself recursively. However, unlike in a FunctionDeclaration, the
-        Identifier in a FunctionExpression cannot be referenced from and
-        does not affect the scope enclosing the FunctionExpression.
-     */
-    if (!function->name().isNull()) {
-        JSStaticScopeObject* functionScopeObject = JSStaticScopeObject::create(callFrame, function->name(), func, ReadOnly | DontDelete);
-        func->setScope(callFrame->globalData(), func->scope()->push(functionScopeObject));
-    }
-
     return func;
 }
 
@@ -3104,7 +3070,7 @@ DEFINE_STUB_FUNCTION(EncodedJSValue, op_call_eval)
         || !callFrame->callerFrame()->codeBlock()->needsFullScopeChain()
         || callFrame->callerFrame()->uncheckedR(callFrame->callerFrame()->codeBlock()->activationRegister()).jsValue());
 
-    callFrame->setScopeChain(callerFrame->scopeChain());
+    callFrame->setScope(callerFrame->scope());
     callFrame->setReturnPC(static_cast<Instruction*>((STUB_RETURN_ADDRESS).value()));
     callFrame->setCodeBlock(0);
 
@@ -3150,21 +3116,20 @@ DEFINE_STUB_FUNCTION(int, has_property)
     return result;
 }
 
-DEFINE_STUB_FUNCTION(JSObject*, op_push_scope)
+DEFINE_STUB_FUNCTION(void, op_push_with_scope)
 {
     STUB_INIT_STACK_FRAME(stackFrame);
 
     JSObject* o = stackFrame.args[0].jsValue().toObject(stackFrame.callFrame);
-    CHECK_FOR_EXCEPTION();
-    stackFrame.callFrame->setScopeChain(stackFrame.callFrame->scopeChain()->push(o));
-    return o;
+    CHECK_FOR_EXCEPTION_VOID();
+    stackFrame.callFrame->setScope(JSWithScope::create(stackFrame.callFrame, o));
 }
 
 DEFINE_STUB_FUNCTION(void, op_pop_scope)
 {
     STUB_INIT_STACK_FRAME(stackFrame);
 
-    stackFrame.callFrame->setScopeChain(stackFrame.callFrame->scopeChain()->pop());
+    stackFrame.callFrame->setScope(stackFrame.callFrame->scope()->next());
 }
 
 DEFINE_STUB_FUNCTION(EncodedJSValue, op_typeof)
@@ -3267,15 +3232,14 @@ DEFINE_STUB_FUNCTION(EncodedJSValue, op_in)
     return JSValue::encode(jsBoolean(baseObj->hasProperty(callFrame, property)));
 }
 
-DEFINE_STUB_FUNCTION(JSObject*, op_push_new_scope)
+DEFINE_STUB_FUNCTION(void, op_push_name_scope)
 {
     STUB_INIT_STACK_FRAME(stackFrame);
 
-    JSObject* scope = JSStaticScopeObject::create(stackFrame.callFrame, stackFrame.args[0].identifier(), stackFrame.args[1].jsValue(), DontDelete);
+    JSNameScope* scope = JSNameScope::create(stackFrame.callFrame, stackFrame.args[0].identifier(), stackFrame.args[1].jsValue(), stackFrame.args[2].int32());
 
     CallFrame* callFrame = stackFrame.callFrame;
-    callFrame->setScopeChain(callFrame->scopeChain()->push(scope));
-    return scope;
+    callFrame->setScope(scope);
 }
 
 DEFINE_STUB_FUNCTION(void, op_jmp_scopes)
@@ -3285,10 +3249,10 @@ DEFINE_STUB_FUNCTION(void, op_jmp_scopes)
     unsigned count = stackFrame.args[0].int32();
     CallFrame* callFrame = stackFrame.callFrame;
 
-    ScopeChainNode* tmp = callFrame->scopeChain();
+    JSScope* tmp = callFrame->scope();
     while (count--)
-        tmp = tmp->pop();
-    callFrame->setScopeChain(tmp);
+        tmp = tmp->next();
+    callFrame->setScope(tmp);
 }
 
 DEFINE_STUB_FUNCTION(void, op_put_by_index)
@@ -3300,7 +3264,7 @@ DEFINE_STUB_FUNCTION(void, op_put_by_index)
 
     JSValue arrayValue = stackFrame.args[0].jsValue();
     ASSERT(isJSArray(arrayValue));
-    asArray(arrayValue)->putDirectIndex(callFrame, property, stackFrame.args[2].jsValue(), false);
+    asArray(arrayValue)->putDirectIndex(callFrame, property, stackFrame.args[2].jsValue());
 }
 
 DEFINE_STUB_FUNCTION(void*, op_switch_imm)
@@ -3419,7 +3383,7 @@ DEFINE_STUB_FUNCTION(void, op_throw_reference_error)
     STUB_INIT_STACK_FRAME(stackFrame);
 
     CallFrame* callFrame = stackFrame.callFrame;
-    UString message = stackFrame.args[0].jsValue().toString(callFrame)->value(callFrame);
+    String message = stackFrame.args[0].jsValue().toString(callFrame)->value(callFrame);
     stackFrame.globalData->exception = createReferenceError(callFrame, message);
     VM_THROW_EXCEPTION_AT_END();
 }
diff --git a/Source/JavaScriptCore/jit/JITStubs.h b/Source/JavaScriptCore/jit/JITStubs.h
index 22a1dd773..e3ef4416e 100644
--- a/Source/JavaScriptCore/jit/JITStubs.h
+++ b/Source/JavaScriptCore/jit/JITStubs.h
@@ -417,8 +417,8 @@ extern "C" {
     JSObject* JIT_STUB cti_op_new_object(STUB_ARGS_DECLARATION) WTF_INTERNAL;
     JSObject* JIT_STUB cti_op_new_regexp(STUB_ARGS_DECLARATION) WTF_INTERNAL;
     JSObject* JIT_STUB cti_op_push_activation(STUB_ARGS_DECLARATION) WTF_INTERNAL;
-    JSObject* JIT_STUB cti_op_push_new_scope(STUB_ARGS_DECLARATION) WTF_INTERNAL;
-    JSObject* JIT_STUB cti_op_push_scope(STUB_ARGS_DECLARATION) WTF_INTERNAL;
+    void JIT_STUB cti_op_push_name_scope(STUB_ARGS_DECLARATION) WTF_INTERNAL;
+    void JIT_STUB cti_op_push_with_scope(STUB_ARGS_DECLARATION) WTF_INTERNAL;
     JSObject* JIT_STUB cti_op_put_by_id_transition_realloc(STUB_ARGS_DECLARATION) WTF_INTERNAL;
     JSPropertyNameIterator* JIT_STUB cti_op_get_pnames(STUB_ARGS_DECLARATION) WTF_INTERNAL;
     int JIT_STUB cti_op_eq(STUB_ARGS_DECLARATION) WTF_INTERNAL;
@@ -468,7 +468,13 @@ extern "C" {
     void* JIT_STUB cti_vm_throw(STUB_ARGS_DECLARATION) REFERENCED_FROM_ASM WTF_INTERNAL;
 } // extern "C"
 
-#endif // ENABLE(JIT)
+#elif ENABLE(LLINT_C_LOOP)
+
+struct JITStackFrame {
+    JSGlobalData* globalData;
+};
+
+#endif // ENABLE(LLINT_C_LOOP)
 
 } // namespace JSC
 
diff --git a/Source/JavaScriptCore/jit/JSInterfaceJIT.h b/Source/JavaScriptCore/jit/JSInterfaceJIT.h
index 6b7dd2184..52f1dd0b0 100644
--- a/Source/JavaScriptCore/jit/JSInterfaceJIT.h
+++ b/Source/JavaScriptCore/jit/JSInterfaceJIT.h
@@ -36,6 +36,8 @@
 #include <wtf/AlwaysInline.h>
 #include <wtf/Vector.h>
 
+#if ENABLE(JIT)
+
 namespace JSC {
     class JSInterfaceJIT : public MacroAssembler {
     public:
@@ -75,6 +77,8 @@ namespace JSC {
         static const FPRegisterID fpRegT1 = X86Registers::xmm1;
         static const FPRegisterID fpRegT2 = X86Registers::xmm2;
         static const FPRegisterID fpRegT3 = X86Registers::xmm3;
+
+        static const RegisterID nonArgGPR1 = X86Registers::eax; // regT0
 #elif CPU(X86)
         static const RegisterID returnValueRegister = X86Registers::eax;
         static const RegisterID cachedResultRegister = X86Registers::eax;
@@ -331,6 +335,8 @@ namespace JSC {
         return Address(base, (static_cast<unsigned>(virtualRegisterIndex) * sizeof(Register)));
     }
 
-}
+} // namespace JSC
+
+#endif // ENABLE(JIT)
 
 #endif // JSInterfaceJIT_h