]> git.saurik.com Git - apple/javascriptcore.git/blobdiff - interpreter/Interpreter.cpp
JavaScriptCore-7601.1.46.3.tar.gz
[apple/javascriptcore.git] / interpreter / Interpreter.cpp
index 56ee7ea9c5f522925fe95949f5ebb08649038028..c997d2c90d3eb01eb90e5828feadfe011b08e2ad 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2008, 2009, 2010 Apple Inc. All rights reserved.
+ * Copyright (C) 2008, 2009, 2010, 2012-2015 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Cameron Zwarich <cwzwarich@uwaterloo.ca>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -11,7 +11,7 @@
  * 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.
- * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ * 3.  Neither the name of Apple Inc. ("Apple") nor the names of
  *     its contributors may be used to endorse or promote products derived
  *     from this software without specific prior written permission.
  *
 #include "config.h"
 #include "Interpreter.h"
 
-#include "Arguments.h"
 #include "BatchedTransitionOptimizer.h"
-#include "CallFrame.h"
 #include "CallFrameClosure.h"
+#include "CallFrameInlines.h"
+#include "ClonedArguments.h"
 #include "CodeBlock.h"
-#include "Collector.h"
+#include "DirectArguments.h"
+#include "Heap.h"
 #include "Debugger.h"
 #include "DebuggerCallFrame.h"
+#include "ErrorInstance.h"
 #include "EvalCodeCache.h"
+#include "Exception.h"
 #include "ExceptionHelpers.h"
-#include "GlobalEvalFunction.h"
-#include "JSActivation.h"
+#include "GetterSetter.h"
 #include "JSArray.h"
-#include "JSByteArray.h"
-#include "JSFunction.h"
+#include "JSBoundFunction.h"
+#include "JSCInlines.h"
+#include "JSLexicalEnvironment.h"
+#include "JSNameScope.h"
 #include "JSNotAnObject.h"
-#include "JSPropertyNameIterator.h"
-#include "LiteralParser.h"
-#include "JSStaticScopeObject.h"
+#include "JSStackInlines.h"
 #include "JSString.h"
+#include "JSWithScope.h"
+#include "LLIntCLoop.h"
+#include "LLIntThunks.h"
+#include "LegacyProfiler.h"
+#include "LiteralParser.h"
 #include "ObjectPrototype.h"
-#include "Operations.h"
 #include "Parser.h"
-#include "Profiler.h"
+#include "ProtoCallFrame.h"
 #include "RegExpObject.h"
 #include "RegExpPrototype.h"
 #include "Register.h"
 #include "SamplingTool.h"
+#include "ScopedArguments.h"
+#include "StackAlignment.h"
+#include "StackVisitor.h"
+#include "StrictEvalActivation.h"
+#include "StrongInlines.h"
+#include "Symbol.h"
+#include "VMEntryScope.h"
+#include "VirtualRegister.h"
+
 #include <limits.h>
 #include <stdio.h>
+#include <wtf/StackStats.h>
+#include <wtf/StdLibExtras.h>
+#include <wtf/StringPrintStream.h>
 #include <wtf/Threading.h>
+#include <wtf/WTFThreadData.h>
+#include <wtf/text/StringBuilder.h>
 
 #if ENABLE(JIT)
 #include "JIT.h"
@@ -70,373 +90,340 @@ using namespace std;
 
 namespace JSC {
 
-static ALWAYS_INLINE unsigned bytecodeOffsetForPC(CallFrame* callFrame, CodeBlock* codeBlock, void* pc)
+String StackFrame::friendlySourceURL() const
 {
-#if ENABLE(JIT)
-    return codeBlock->getBytecodeIndex(callFrame, ReturnAddressPtr(pc));
-#else
-    UNUSED_PARAM(callFrame);
-    return static_cast<Instruction*>(pc) - codeBlock->instructions().begin();
-#endif
+    String traceLine;
+    
+    switch (codeType) {
+    case StackFrameEvalCode:
+    case StackFrameFunctionCode:
+    case StackFrameGlobalCode:
+        if (!sourceURL.isEmpty())
+            traceLine = sourceURL.impl();
+        break;
+    case StackFrameNativeCode:
+        traceLine = "[native code]";
+        break;
+    }
+    return traceLine.isNull() ? emptyString() : traceLine;
 }
 
-// Returns the depth of the scope chain within a given call frame.
-static int depth(CodeBlock* codeBlock, ScopeChain& sc)
+String StackFrame::friendlyFunctionName(CallFrame* callFrame) const
 {
-    if (!codeBlock->needsFullScopeChain())
-        return 0;
-    return sc.localDepth();
+    String traceLine;
+    JSObject* stackFrameCallee = callee.get();
+
+    switch (codeType) {
+    case StackFrameEvalCode:
+        traceLine = "eval code";
+        break;
+    case StackFrameNativeCode:
+        if (callee)
+            traceLine = getCalculatedDisplayName(callFrame, stackFrameCallee).impl();
+        break;
+    case StackFrameFunctionCode:
+        traceLine = getCalculatedDisplayName(callFrame, stackFrameCallee).impl();
+        break;
+    case StackFrameGlobalCode:
+        traceLine = "global code";
+        break;
+    }
+    return traceLine.isNull() ? emptyString() : traceLine;
 }
 
-#if USE(INTERPRETER)
-NEVER_INLINE bool Interpreter::resolve(CallFrame* callFrame, Instruction* vPC, JSValue& exceptionValue)
+JSValue eval(CallFrame* callFrame)
 {
-    int dst = vPC[1].u.operand;
-    int property = vPC[2].u.operand;
-
-    ScopeChainNode* scopeChain = callFrame->scopeChain();
-    ScopeChainIterator iter = scopeChain->begin();
-    ScopeChainIterator end = scopeChain->end();
-    ASSERT(iter != end);
+    if (!callFrame->argumentCount())
+        return jsUndefined();
 
-    CodeBlock* codeBlock = callFrame->codeBlock();
-    Identifier& ident = codeBlock->identifier(property);
-    do {
-        JSObject* o = *iter;
-        PropertySlot slot(o);
-        if (o->getPropertySlot(callFrame, ident, slot)) {
-            JSValue result = slot.getValue(callFrame, ident);
-            exceptionValue = callFrame->globalData().exception;
-            if (exceptionValue)
-                return false;
-            callFrame->r(dst) = JSValue(result);
-            return true;
+    JSValue program = callFrame->argument(0);
+    if (!program.isString())
+        return program;
+    
+    TopCallFrameSetter topCallFrame(callFrame->vm(), callFrame);
+    String programSource = asString(program)->value(callFrame);
+    if (callFrame->hadException())
+        return JSValue();
+    
+    CallFrame* callerFrame = callFrame->callerFrame();
+    CodeBlock* callerCodeBlock = callerFrame->codeBlock();
+    JSScope* callerScopeChain = callerFrame->uncheckedR(callerCodeBlock->scopeRegister().offset()).Register::scope();
+    EvalExecutable* eval = callerCodeBlock->evalCodeCache().tryGet(callerCodeBlock->isStrictMode(), programSource, callerScopeChain);
+
+    if (!eval) {
+        if (!callerCodeBlock->isStrictMode()) {
+            if (programSource.is8Bit()) {
+                LiteralParser<LChar> preparser(callFrame, programSource.characters8(), programSource.length(), NonStrictJSON);
+                if (JSValue parsedObject = preparser.tryLiteralParse())
+                    return parsedObject;
+            } else {
+                LiteralParser<UChar> preparser(callFrame, programSource.characters16(), programSource.length(), NonStrictJSON);
+                if (JSValue parsedObject = preparser.tryLiteralParse())
+                    return parsedObject;                
+            }
         }
-    } while (++iter != end);
-    exceptionValue = createUndefinedVariableError(callFrame, ident, vPC - codeBlock->instructions().begin(), codeBlock);
-    return false;
-}
-
-NEVER_INLINE bool Interpreter::resolveSkip(CallFrame* callFrame, Instruction* vPC, JSValue& exceptionValue)
-{
-    CodeBlock* codeBlock = callFrame->codeBlock();
+        
+        // If the literal parser bailed, it should not have thrown exceptions.
+        ASSERT(!callFrame->vm().exception());
 
-    int dst = vPC[1].u.operand;
-    int property = vPC[2].u.operand;
-    int skip = vPC[3].u.operand + codeBlock->needsFullScopeChain();
-
-    ScopeChainNode* scopeChain = callFrame->scopeChain();
-    ScopeChainIterator iter = scopeChain->begin();
-    ScopeChainIterator end = scopeChain->end();
-    ASSERT(iter != end);
-    while (skip--) {
-        ++iter;
-        ASSERT(iter != end);
+        ThisTDZMode thisTDZMode = callerCodeBlock->unlinkedCodeBlock()->constructorKind() == ConstructorKind::Derived ? ThisTDZMode::AlwaysCheck : ThisTDZMode::CheckIfNeeded;
+        eval = callerCodeBlock->evalCodeCache().getSlow(callFrame, callerCodeBlock->ownerExecutable(), callerCodeBlock->isStrictMode(), thisTDZMode, programSource, callerScopeChain);
+        if (!eval)
+            return jsUndefined();
     }
-    Identifier& ident = codeBlock->identifier(property);
-    do {
-        JSObject* o = *iter;
-        PropertySlot slot(o);
-        if (o->getPropertySlot(callFrame, ident, slot)) {
-            JSValue result = slot.getValue(callFrame, ident);
-            exceptionValue = callFrame->globalData().exception;
-            if (exceptionValue)
-                return false;
-            callFrame->r(dst) = JSValue(result);
-            return true;
-        }
-    } while (++iter != end);
-    exceptionValue = createUndefinedVariableError(callFrame, ident, vPC - codeBlock->instructions().begin(), codeBlock);
-    return false;
+
+    JSValue thisValue = callerFrame->thisValue();
+    Interpreter* interpreter = callFrame->vm().interpreter;
+    return interpreter->execute(eval, callFrame, thisValue, callerScopeChain);
 }
 
-NEVER_INLINE bool Interpreter::resolveGlobal(CallFrame* callFrame, Instruction* vPC, JSValue& exceptionValue)
+unsigned sizeOfVarargs(CallFrame* callFrame, JSValue arguments, uint32_t firstVarArgOffset)
 {
-    int dst = vPC[1].u.operand;
-    JSGlobalObject* globalObject = static_cast<JSGlobalObject*>(vPC[2].u.jsCell);
-    ASSERT(globalObject->isGlobalObject());
-    int property = vPC[3].u.operand;
-    Structure* structure = vPC[4].u.structure;
-    int offset = vPC[5].u.operand;
-
-    if (structure == globalObject->structure()) {
-        callFrame->r(dst) = JSValue(globalObject->getDirectOffset(offset));
-        return true;
+    if (UNLIKELY(!arguments.isCell())) {
+        if (arguments.isUndefinedOrNull())
+            return 0;
+        
+        callFrame->vm().throwException(callFrame, createInvalidFunctionApplyParameterError(callFrame, arguments));
+        return 0;
     }
-
-    CodeBlock* codeBlock = callFrame->codeBlock();
-    Identifier& ident = codeBlock->identifier(property);
-    PropertySlot slot(globalObject);
-    if (globalObject->getPropertySlot(callFrame, ident, slot)) {
-        JSValue result = slot.getValue(callFrame, ident);
-        if (slot.isCacheable() && !globalObject->structure()->isUncacheableDictionary() && slot.slotBase() == globalObject) {
-            if (vPC[4].u.structure)
-                vPC[4].u.structure->deref();
-            globalObject->structure()->ref();
-            vPC[4] = globalObject->structure();
-            vPC[5] = slot.cachedOffset();
-            callFrame->r(dst) = JSValue(result);
-            return true;
-        }
-
-        exceptionValue = callFrame->globalData().exception;
-        if (exceptionValue)
-            return false;
-        callFrame->r(dst) = JSValue(result);
-        return true;
+    
+    JSCell* cell = arguments.asCell();
+    unsigned length;
+    switch (cell->type()) {
+    case DirectArgumentsType:
+        length = jsCast<DirectArguments*>(cell)->length(callFrame);
+        break;
+    case ScopedArgumentsType:
+        length =jsCast<ScopedArguments*>(cell)->length(callFrame);
+        break;
+    case StringType:
+        callFrame->vm().throwException(callFrame, createInvalidFunctionApplyParameterError(callFrame,  arguments));
+        return 0;
+    default:
+        ASSERT(arguments.isObject());
+        if (isJSArray(cell))
+            length = jsCast<JSArray*>(cell)->length();
+        else
+            length = jsCast<JSObject*>(cell)->get(callFrame, callFrame->propertyNames().length).toUInt32(callFrame);
+        break;
     }
-
-    exceptionValue = createUndefinedVariableError(callFrame, ident, vPC - codeBlock->instructions().begin(), codeBlock);
-    return false;
+    
+    if (length >= firstVarArgOffset)
+        length -= firstVarArgOffset;
+    else
+        length = 0;
+    
+    return length;
 }
 
-NEVER_INLINE void Interpreter::resolveBase(CallFrame* callFrame, Instruction* vPC)
+unsigned sizeFrameForVarargs(CallFrame* callFrame, JSStack* stack, JSValue arguments, unsigned numUsedStackSlots, uint32_t firstVarArgOffset)
 {
-    int dst = vPC[1].u.operand;
-    int property = vPC[2].u.operand;
-    callFrame->r(dst) = JSValue(JSC::resolveBase(callFrame, callFrame->codeBlock()->identifier(property), callFrame->scopeChain()));
+    unsigned length = sizeOfVarargs(callFrame, arguments, firstVarArgOffset);
+    
+    CallFrame* calleeFrame = calleeFrameForVarargs(callFrame, numUsedStackSlots, length + 1);
+    if (length > maxArguments || !stack->ensureCapacityFor(calleeFrame->registers())) {
+        throwStackOverflowError(callFrame);
+        return 0;
+    }
+    
+    return length;
 }
 
-NEVER_INLINE bool Interpreter::resolveBaseAndProperty(CallFrame* callFrame, Instruction* vPC, JSValue& exceptionValue)
+void loadVarargs(CallFrame* callFrame, VirtualRegister firstElementDest, JSValue arguments, uint32_t offset, uint32_t length)
 {
-    int baseDst = vPC[1].u.operand;
-    int propDst = vPC[2].u.operand;
-    int property = vPC[3].u.operand;
-
-    ScopeChainNode* scopeChain = callFrame->scopeChain();
-    ScopeChainIterator iter = scopeChain->begin();
-    ScopeChainIterator end = scopeChain->end();
-
-    // FIXME: add scopeDepthIsZero optimization
-
-    ASSERT(iter != end);
-
-    CodeBlock* codeBlock = callFrame->codeBlock();
-    Identifier& ident = codeBlock->identifier(property);
-    JSObject* base;
-    do {
-        base = *iter;
-        PropertySlot slot(base);
-        if (base->getPropertySlot(callFrame, ident, slot)) {
-            JSValue result = slot.getValue(callFrame, ident);
-            exceptionValue = callFrame->globalData().exception;
-            if (exceptionValue)
-                return false;
-            callFrame->r(propDst) = JSValue(result);
-            callFrame->r(baseDst) = JSValue(base);
-            return true;
+    if (UNLIKELY(!arguments.isCell()))
+        return;
+    
+    JSCell* cell = arguments.asCell();
+    switch (cell->type()) {
+    case DirectArgumentsType:
+        jsCast<DirectArguments*>(cell)->copyToArguments(callFrame, firstElementDest, offset, length);
+        return;
+    case ScopedArgumentsType:
+        jsCast<ScopedArguments*>(cell)->copyToArguments(callFrame, firstElementDest, offset, length);
+        return;
+    default: {
+        ASSERT(arguments.isObject());
+        JSObject* object = jsCast<JSObject*>(cell);
+        if (isJSArray(object)) {
+            jsCast<JSArray*>(object)->copyToArguments(callFrame, firstElementDest, offset, length);
+            return;
         }
-        ++iter;
-    } while (iter != end);
-
-    exceptionValue = createUndefinedVariableError(callFrame, ident, vPC - codeBlock->instructions().begin(), codeBlock);
-    return false;
+        unsigned i;
+        for (i = 0; i < length && object->canGetIndexQuickly(i + offset); ++i)
+            callFrame->r(firstElementDest + i) = object->getIndexQuickly(i + offset);
+        for (; i < length; ++i)
+            callFrame->r(firstElementDest + i) = object->get(callFrame, i + offset);
+        return;
+    } }
 }
 
-#endif // USE(INTERPRETER)
-
-ALWAYS_INLINE CallFrame* Interpreter::slideRegisterWindowForCall(CodeBlock* newCodeBlock, RegisterFile* registerFile, CallFrame* callFrame, size_t registerOffset, int argc)
+void setupVarargsFrame(CallFrame* callFrame, CallFrame* newCallFrame, JSValue arguments, uint32_t offset, uint32_t length)
 {
-    Register* r = callFrame->registers();
-    Register* newEnd = r + registerOffset + newCodeBlock->m_numCalleeRegisters;
-
-    if (LIKELY(argc == newCodeBlock->m_numParameters)) { // correct number of arguments
-        if (UNLIKELY(!registerFile->grow(newEnd)))
-            return 0;
-        r += registerOffset;
-    } else if (argc < newCodeBlock->m_numParameters) { // too few arguments -- fill in the blanks
-        size_t omittedArgCount = newCodeBlock->m_numParameters - argc;
-        registerOffset += omittedArgCount;
-        newEnd += omittedArgCount;
-        if (!registerFile->grow(newEnd))
-            return 0;
-        r += registerOffset;
-
-        Register* argv = r - RegisterFile::CallFrameHeaderSize - omittedArgCount;
-        for (size_t i = 0; i < omittedArgCount; ++i)
-            argv[i] = jsUndefined();
-    } else { // too many arguments -- copy expected arguments, leaving the extra arguments behind
-        size_t numParameters = newCodeBlock->m_numParameters;
-        registerOffset += numParameters;
-        newEnd += numParameters;
-
-        if (!registerFile->grow(newEnd))
-            return 0;
-        r += registerOffset;
-
-        Register* argv = r - RegisterFile::CallFrameHeaderSize - numParameters - argc;
-        for (size_t i = 0; i < numParameters; ++i)
-            argv[i + argc] = argv[i];
-    }
-
-    return CallFrame::create(r);
+    VirtualRegister calleeFrameOffset(newCallFrame - callFrame);
+    
+    loadVarargs(
+        callFrame,
+        calleeFrameOffset + CallFrame::argumentOffset(0),
+        arguments, offset, length);
+    
+    newCallFrame->setArgumentCountIncludingThis(length + 1);
 }
 
-#if USE(INTERPRETER)
-static NEVER_INLINE bool isInvalidParamForIn(CallFrame* callFrame, CodeBlock* codeBlock, const Instruction* vPC, JSValue value, JSValue& exceptionData)
+void setupVarargsFrameAndSetThis(CallFrame* callFrame, CallFrame* newCallFrame, JSValue thisValue, JSValue arguments, uint32_t firstVarArgOffset, uint32_t length)
 {
-    if (value.isObject())
-        return false;
-    exceptionData = createInvalidParamError(callFrame, "in" , value, vPC - codeBlock->instructions().begin(), codeBlock);
-    return true;
+    setupVarargsFrame(callFrame, newCallFrame, arguments, firstVarArgOffset, length);
+    newCallFrame->setThisValue(thisValue);
 }
 
-static NEVER_INLINE bool isInvalidParamForInstanceOf(CallFrame* callFrame, CodeBlock* codeBlock, const Instruction* vPC, JSValue value, JSValue& exceptionData)
+Interpreter::Interpreter(VM& vm)
+    : m_sampleEntryDepth(0)
+    , m_vm(vm)
+    , m_stack(vm)
+    , m_errorHandlingModeReentry(0)
+#if !ASSERT_DISABLED
+    , m_initialized(false)
+#endif
 {
-    if (value.isObject() && asObject(value)->structure()->typeInfo().implementsHasInstance())
-        return false;
-    exceptionData = createInvalidParamError(callFrame, "instanceof" , value, vPC - codeBlock->instructions().begin(), codeBlock);
-    return true;
 }
-#endif
 
-NEVER_INLINE JSValue Interpreter::callEval(CallFrame* callFrame, RegisterFile* registerFile, Register* argv, int argc, int registerOffset, JSValue& exceptionValue)
+Interpreter::~Interpreter()
 {
-    if (argc < 2)
-        return jsUndefined();
-
-    JSValue program = argv[1].jsValue();
-
-    if (!program.isString())
-        return program;
-
-    UString programSource = asString(program)->value(callFrame);
-
-    LiteralParser preparser(callFrame, programSource, LiteralParser::NonStrictJSON);
-    if (JSValue parsedObject = preparser.tryLiteralParse())
-        return parsedObject;
-
-    ScopeChainNode* scopeChain = callFrame->scopeChain();
-    CodeBlock* codeBlock = callFrame->codeBlock();
-    RefPtr<EvalExecutable> eval = codeBlock->evalCodeCache().get(callFrame, programSource, scopeChain, exceptionValue);
-
-    JSValue result = jsUndefined();
-    if (eval)
-        result = callFrame->globalData().interpreter->execute(eval.get(), callFrame, callFrame->thisValue().toThisObject(callFrame), callFrame->registers() - registerFile->start() + registerOffset, scopeChain, &exceptionValue);
-
-    return result;
 }
 
-Interpreter::Interpreter()
-    : m_sampleEntryDepth(0)
-    , m_reentryDepth(0)
+void Interpreter::initialize(bool canUseJIT)
 {
-#if HAVE(COMPUTED_GOTO)
-    privateExecute(InitializeAndReturn, 0, 0, 0);
+    UNUSED_PARAM(canUseJIT);
 
+#if ENABLE(COMPUTED_GOTO_OPCODES)
+    m_opcodeTable = LLInt::opcodeMap();
     for (int i = 0; i < numOpcodeIDs; ++i)
         m_opcodeIDTable.add(m_opcodeTable[i], static_cast<OpcodeID>(i));
-#endif // HAVE(COMPUTED_GOTO)
+#endif
+
+#if !ASSERT_DISABLED
+    m_initialized = true;
+#endif
 
 #if ENABLE(OPCODE_SAMPLING)
     enableSampler();
 #endif
 }
 
-#ifndef NDEBUG
+#ifdef NDEBUG
+
+void Interpreter::dumpCallFrame(CallFrame*)
+{
+}
+
+#else
 
 void Interpreter::dumpCallFrame(CallFrame* callFrame)
 {
-    callFrame->codeBlock()->dump(callFrame);
+    callFrame->codeBlock()->dumpBytecode();
     dumpRegisters(callFrame);
 }
 
+class DumpRegisterFunctor {
+public:
+    DumpRegisterFunctor(const Register*& it)
+        : m_hasSkippedFirstFrame(false)
+        , m_it(it)
+    {
+    }
+
+    StackVisitor::Status operator()(StackVisitor& visitor)
+    {
+        if (!m_hasSkippedFirstFrame) {
+            m_hasSkippedFirstFrame = true;
+            return StackVisitor::Continue;
+        }
+
+        unsigned line = 0;
+        unsigned unusedColumn = 0;
+        visitor->computeLineAndColumn(line, unusedColumn);
+        dataLogF("[ReturnVPC]                | %10p | %d (line %d)\n", m_it, visitor->bytecodeOffset(), line);
+        --m_it;
+        return StackVisitor::Done;
+    }
+
+private:
+    bool m_hasSkippedFirstFrame;
+    const Register*& m_it;
+};
+
 void Interpreter::dumpRegisters(CallFrame* callFrame)
 {
-    printf("Register frame: \n\n");
-    printf("-----------------------------------------------------------------------------\n");
-    printf("            use            |   address  |                value               \n");
-    printf("-----------------------------------------------------------------------------\n");
+    dataLogF("Register frame: \n\n");
+    dataLogF("-----------------------------------------------------------------------------\n");
+    dataLogF("            use            |   address  |                value               \n");
+    dataLogF("-----------------------------------------------------------------------------\n");
 
     CodeBlock* codeBlock = callFrame->codeBlock();
-    RegisterFile* registerFile = &callFrame->scopeChain()->globalObject->globalData()->interpreter->registerFile();
     const Register* it;
     const Register* end;
-    JSValue v;
-
-    if (codeBlock->codeType() == GlobalCode) {
-        it = registerFile->lastGlobal();
-        end = it + registerFile->numGlobals();
-        while (it != end) {
-            v = (*it).jsValue();
-#if USE(JSVALUE32_64)
-            printf("[global var]               | %10p | %-16s 0x%llx \n", it, v.description(), JSValue::encode(v));
-#else
-            printf("[global var]               | %10p | %-16s %p \n", it, v.description(), JSValue::encode(v));
-#endif
-            ++it;
-        }
-        printf("-----------------------------------------------------------------------------\n");
+
+    it = callFrame->registers() + JSStack::ThisArgument + callFrame->argumentCount();
+    end = callFrame->registers() + JSStack::ThisArgument - 1;
+    while (it > end) {
+        JSValue v = it->jsValue();
+        int registerNumber = it - callFrame->registers();
+        String name = codeBlock->nameForRegister(VirtualRegister(registerNumber));
+        dataLogF("[r% 3d %14s]      | %10p | %-16s 0x%lld \n", registerNumber, name.ascii().data(), it, toCString(v).data(), (long long)JSValue::encode(v));
+        --it;
     }
     
-    it = callFrame->registers() - RegisterFile::CallFrameHeaderSize - codeBlock->m_numParameters;
-    v = (*it).jsValue();
-#if USE(JSVALUE32_64)
-    printf("[this]                     | %10p | %-16s 0x%llx \n", it, v.description(), JSValue::encode(v)); ++it;
-#else
-    printf("[this]                     | %10p | %-16s %p \n", it, v.description(), JSValue::encode(v)); ++it;
-#endif
-    end = it + max(codeBlock->m_numParameters - 1, 0); // - 1 to skip "this"
-    if (it != end) {
-        do {
-            v = (*it).jsValue();
-#if USE(JSVALUE32_64)
-            printf("[param]                    | %10p | %-16s 0x%llx \n", it, v.description(), JSValue::encode(v));
-#else
-            printf("[param]                    | %10p | %-16s %p \n", it, v.description(), JSValue::encode(v));
+    dataLogF("-----------------------------------------------------------------------------\n");
+    dataLogF("[ArgumentCount]            | %10p | %lu \n", it, (unsigned long) callFrame->argumentCount());
+    --it;
+    dataLogF("[CallerFrame]              | %10p | %p \n", it, callFrame->callerFrame());
+    --it;
+    dataLogF("[Callee]                   | %10p | %p \n", it, callFrame->callee());
+    --it;
+    // FIXME: Remove the next decrement when the ScopeChain slot is removed from the call header
+    --it;
+#if ENABLE(JIT)
+    AbstractPC pc = callFrame->abstractReturnPC(callFrame->vm());
+    if (pc.hasJITReturnAddress())
+        dataLogF("[ReturnJITPC]              | %10p | %p \n", it, pc.jitReturnAddress().value());
 #endif
-            ++it;
-        } while (it != end);
-    }
-    printf("-----------------------------------------------------------------------------\n");
-    printf("[CodeBlock]                | %10p | %p \n", it, (*it).codeBlock()); ++it;
-    printf("[ScopeChain]               | %10p | %p \n", it, (*it).scopeChain()); ++it;
-    printf("[CallerRegisters]          | %10p | %d \n", it, (*it).i()); ++it;
-    printf("[ReturnPC]                 | %10p | %p \n", it, (*it).vPC()); ++it;
-    printf("[ReturnValueRegister]      | %10p | %d \n", it, (*it).i()); ++it;
-    printf("[ArgumentCount]            | %10p | %d \n", it, (*it).i()); ++it;
-    printf("[Callee]                   | %10p | %p \n", it, (*it).function()); ++it;
-    printf("[OptionalCalleeArguments]  | %10p | %p \n", it, (*it).arguments()); ++it;
-    printf("-----------------------------------------------------------------------------\n");
-
-    int registerCount = 0;
-
-    end = it + codeBlock->m_numVars;
+
+    DumpRegisterFunctor functor(it);
+    callFrame->iterate(functor);
+
+    dataLogF("[CodeBlock]                | %10p | %p \n", it, callFrame->codeBlock());
+    --it;
+    dataLogF("-----------------------------------------------------------------------------\n");
+
+    end = it - codeBlock->m_numVars;
     if (it != end) {
         do {
-            v = (*it).jsValue();
-#if USE(JSVALUE32_64)
-            printf("[r%2d]                      | %10p | %-16s 0x%llx \n", registerCount, it, v.description(), JSValue::encode(v));
-#else
-            printf("[r%2d]                      | %10p | %-16s %p \n", registerCount, it, v.description(), JSValue::encode(v));
-#endif
-            ++it;
-            ++registerCount;
+            JSValue v = it->jsValue();
+            int registerNumber = it - callFrame->registers();
+            String name = codeBlock->nameForRegister(VirtualRegister(registerNumber));
+            dataLogF("[r% 3d %14s]      | %10p | %-16s 0x%lld \n", registerNumber, name.ascii().data(), it, toCString(v).data(), (long long)JSValue::encode(v));
+            --it;
         } while (it != end);
     }
-    printf("-----------------------------------------------------------------------------\n");
+    dataLogF("-----------------------------------------------------------------------------\n");
 
-    end = it + codeBlock->m_numCalleeRegisters - codeBlock->m_numVars;
+    end = it - codeBlock->m_numCalleeRegisters + codeBlock->m_numVars;
     if (it != end) {
         do {
-            v = (*it).jsValue();
-#if USE(JSVALUE32_64)
-            printf("[r%2d]                      | %10p | %-16s 0x%llx \n", registerCount, it, v.description(), JSValue::encode(v));
-#else
-            printf("[r%2d]                      | %10p | %-16s %p \n", registerCount, it, v.description(), JSValue::encode(v));
-#endif
-            ++it;
-            ++registerCount;
+            JSValue v = (*it).jsValue();
+            int registerNumber = it - callFrame->registers();
+            dataLogF("[r% 3d]                     | %10p | %-16s 0x%lld \n", registerNumber, it, toCString(v).data(), (long long)JSValue::encode(v));
+            --it;
         } while (it != end);
     }
-    printf("-----------------------------------------------------------------------------\n");
+    dataLogF("-----------------------------------------------------------------------------\n");
 }
 
 #endif
 
 bool Interpreter::isOpcode(Opcode opcode)
 {
-#if HAVE(COMPUTED_GOTO)
+#if ENABLE(COMPUTED_GOTO_OPCODES)
     return opcode != HashTraits<Opcode>::emptyValue()
         && !HashTraits<Opcode>::isDeletedValue(opcode)
         && m_opcodeIDTable.contains(opcode);
@@ -445,3544 +432,805 @@ bool Interpreter::isOpcode(Opcode opcode)
 #endif
 }
 
-NEVER_INLINE bool Interpreter::unwindCallFrame(CallFrame*& callFrame, JSValue exceptionValue, unsigned& bytecodeOffset, CodeBlock*& codeBlock)
+static bool unwindCallFrame(StackVisitor& visitor)
 {
-    CodeBlock* oldCodeBlock = codeBlock;
-    ScopeChainNode* scopeChain = callFrame->scopeChain();
-
-    if (Debugger* debugger = callFrame->dynamicGlobalObject()->debugger()) {
-        DebuggerCallFrame debuggerCallFrame(callFrame, exceptionValue);
-        if (callFrame->callee())
-            debugger->returnEvent(debuggerCallFrame, codeBlock->ownerExecutable()->sourceID(), codeBlock->ownerExecutable()->lastLine());
+    CallFrame* callFrame = visitor->callFrame();
+    if (Debugger* debugger = callFrame->vmEntryGlobalObject()->debugger()) {
+        SuspendExceptionScope scope(&callFrame->vm());
+        if (jsDynamicCast<JSFunction*>(callFrame->callee()))
+            debugger->returnEvent(callFrame);
         else
-            debugger->didExecuteProgram(debuggerCallFrame, codeBlock->ownerExecutable()->sourceID(), codeBlock->ownerExecutable()->lastLine());
+            debugger->didExecuteProgram(callFrame);
+        ASSERT(!callFrame->hadException());
     }
 
-    if (Profiler* profiler = *Profiler::enabledProfilerReference()) {
-        if (callFrame->callee())
-            profiler->didExecute(callFrame, callFrame->callee());
-        else
-            profiler->didExecute(callFrame, codeBlock->ownerExecutable()->sourceURL(), codeBlock->ownerExecutable()->lineNo());
+    return !visitor->callerIsVMEntryFrame();
+}
+
+static StackFrameCodeType getStackFrameCodeType(StackVisitor& visitor)
+{
+    switch (visitor->codeType()) {
+    case StackVisitor::Frame::Eval:
+        return StackFrameEvalCode;
+    case StackVisitor::Frame::Function:
+        return StackFrameFunctionCode;
+    case StackVisitor::Frame::Global:
+        return StackFrameGlobalCode;
+    case StackVisitor::Frame::Native:
+        ASSERT_NOT_REACHED();
+        return StackFrameNativeCode;
     }
+    RELEASE_ASSERT_NOT_REACHED();
+    return StackFrameGlobalCode;
+}
 
-    // If this call frame created an activation or an 'arguments' object, tear it off.
-    if (oldCodeBlock->codeType() == FunctionCode && oldCodeBlock->needsFullScopeChain()) {
-        while (!scopeChain->object->inherits(&JSActivation::info))
-            scopeChain = scopeChain->pop();
-        static_cast<JSActivation*>(scopeChain->object)->copyRegisters(callFrame->optionalCalleeArguments());
-    } else if (Arguments* arguments = callFrame->optionalCalleeArguments()) {
-        if (!arguments->isTornOff())
-            arguments->copyRegisters();
+void StackFrame::computeLineAndColumn(unsigned& line, unsigned& column)
+{
+    if (!codeBlock) {
+        line = 0;
+        column = 0;
+        return;
     }
 
-    if (oldCodeBlock->needsFullScopeChain())
-        scopeChain->deref();
+    int divot = 0;
+    int unusedStartOffset = 0;
+    int unusedEndOffset = 0;
+    unsigned divotLine = 0;
+    unsigned divotColumn = 0;
+    expressionInfo(divot, unusedStartOffset, unusedEndOffset, divotLine, divotColumn);
 
-    void* returnPC = callFrame->returnPC();
-    callFrame = callFrame->callerFrame();
-    if (callFrame->hasHostCallFrameFlag())
-        return false;
+    line = divotLine + lineOffset;
+    column = divotColumn + (divotLine ? 1 : firstLineColumnOffset);
 
-    codeBlock = callFrame->codeBlock();
-    bytecodeOffset = bytecodeOffsetForPC(callFrame, codeBlock, returnPC);
-    return true;
+    if (executable->hasOverrideLineNumber())
+        line = executable->overrideLineNumber();
 }
 
-NEVER_INLINE HandlerInfo* Interpreter::throwException(CallFrame*& callFrame, JSValue& exceptionValue, unsigned bytecodeOffset, bool explicitThrow)
+void StackFrame::expressionInfo(int& divot, int& startOffset, int& endOffset, unsigned& line, unsigned& column)
 {
-    // Set up the exception object
+    codeBlock->expressionRangeForBytecodeOffset(bytecodeOffset, divot, startOffset, endOffset, line, column);
+    divot += characterOffset;
+}
 
-    CodeBlock* codeBlock = callFrame->codeBlock();
-    if (exceptionValue.isObject()) {
-        JSObject* exception = asObject(exceptionValue);
-        if (exception->isNotAnObjectErrorStub()) {
-            exception = createNotAnObjectError(callFrame, static_cast<JSNotAnObjectErrorStub*>(exception), bytecodeOffset, codeBlock);
-            exceptionValue = exception;
-        } else {
-            if (!exception->hasProperty(callFrame, Identifier(callFrame, "line")) && 
-                !exception->hasProperty(callFrame, Identifier(callFrame, "sourceId")) && 
-                !exception->hasProperty(callFrame, Identifier(callFrame, "sourceURL")) && 
-                !exception->hasProperty(callFrame, Identifier(callFrame, expressionBeginOffsetPropertyName)) && 
-                !exception->hasProperty(callFrame, Identifier(callFrame, expressionCaretOffsetPropertyName)) && 
-                !exception->hasProperty(callFrame, Identifier(callFrame, expressionEndOffsetPropertyName))) {
-                if (explicitThrow) {
-                    int startOffset = 0;
-                    int endOffset = 0;
-                    int divotPoint = 0;
-                    int line = codeBlock->expressionRangeForBytecodeOffset(callFrame, bytecodeOffset, divotPoint, startOffset, endOffset);
-                    exception->putWithAttributes(callFrame, Identifier(callFrame, "line"), jsNumber(callFrame, line), ReadOnly | DontDelete);
-                    
-                    // We only hit this path for error messages and throw statements, which don't have a specific failure position
-                    // So we just give the full range of the error/throw statement.
-                    exception->putWithAttributes(callFrame, Identifier(callFrame, expressionBeginOffsetPropertyName), jsNumber(callFrame, divotPoint - startOffset), ReadOnly | DontDelete);
-                    exception->putWithAttributes(callFrame, Identifier(callFrame, expressionEndOffsetPropertyName), jsNumber(callFrame, divotPoint + endOffset), ReadOnly | DontDelete);
-                } else
-                    exception->putWithAttributes(callFrame, Identifier(callFrame, "line"), jsNumber(callFrame, codeBlock->lineNumberForBytecodeOffset(callFrame, bytecodeOffset)), ReadOnly | DontDelete);
-                exception->putWithAttributes(callFrame, Identifier(callFrame, "sourceId"), jsNumber(callFrame, codeBlock->ownerExecutable()->sourceID()), ReadOnly | DontDelete);
-                exception->putWithAttributes(callFrame, Identifier(callFrame, "sourceURL"), jsOwnedString(callFrame, codeBlock->ownerExecutable()->sourceURL()), ReadOnly | DontDelete);
-            }
-            
-            if (exception->isWatchdogException()) {
-                while (unwindCallFrame(callFrame, exceptionValue, bytecodeOffset, codeBlock)) {
-                    // Don't need handler checks or anything, we just want to unroll all the JS callframes possible.
-                }
-                return 0;
+String StackFrame::toString(CallFrame* callFrame)
+{
+    StringBuilder traceBuild;
+    String functionName = friendlyFunctionName(callFrame);
+    String sourceURL = friendlySourceURL();
+    traceBuild.append(functionName);
+    if (!sourceURL.isEmpty()) {
+        if (!functionName.isEmpty())
+            traceBuild.append('@');
+        traceBuild.append(sourceURL);
+        if (codeType != StackFrameNativeCode) {
+            unsigned line;
+            unsigned column;
+            computeLineAndColumn(line, column);
+
+            traceBuild.append(':');
+            traceBuild.appendNumber(line);
+            traceBuild.append(':');
+            traceBuild.appendNumber(column);
+        }
+    }
+    return traceBuild.toString().impl();
+}
+
+class GetStackTraceFunctor {
+public:
+    GetStackTraceFunctor(VM& vm, Vector<StackFrame>& results, size_t remainingCapacity)
+        : m_vm(vm)
+        , m_results(results)
+        , m_remainingCapacityForFrameCapture(remainingCapacity)
+    {
+    }
+
+    StackVisitor::Status operator()(StackVisitor& visitor)
+    {
+        VM& vm = m_vm;
+        if (m_remainingCapacityForFrameCapture) {
+            if (visitor->isJSFrame() && !visitor->codeBlock()->unlinkedCodeBlock()->isBuiltinFunction()) {
+                CodeBlock* codeBlock = visitor->codeBlock();
+                StackFrame s = {
+                    Strong<JSObject>(vm, visitor->callee()),
+                    getStackFrameCodeType(visitor),
+                    Strong<ScriptExecutable>(vm, codeBlock->ownerExecutable()),
+                    Strong<UnlinkedCodeBlock>(vm, codeBlock->unlinkedCodeBlock()),
+                    codeBlock->source(),
+                    codeBlock->ownerExecutable()->firstLine(),
+                    codeBlock->firstLineColumnOffset(),
+                    codeBlock->sourceOffset(),
+                    visitor->bytecodeOffset(),
+                    visitor->sourceURL()
+                };
+                m_results.append(s);
+            } else {
+                StackFrame s = { Strong<JSObject>(vm, visitor->callee()), StackFrameNativeCode, Strong<ScriptExecutable>(), Strong<UnlinkedCodeBlock>(), 0, 0, 0, 0, 0, String()};
+                m_results.append(s);
             }
+    
+            m_remainingCapacityForFrameCapture--;
+            return StackVisitor::Continue;
         }
+        return StackVisitor::Done;
     }
 
-    if (Debugger* debugger = callFrame->dynamicGlobalObject()->debugger()) {
-        DebuggerCallFrame debuggerCallFrame(callFrame, exceptionValue);
-        bool hasHandler = codeBlock->handlerForBytecodeOffset(bytecodeOffset);
-        debugger->exception(debuggerCallFrame, codeBlock->ownerExecutable()->sourceID(), codeBlock->lineNumberForBytecodeOffset(callFrame, bytecodeOffset), hasHandler);
+private:
+    VM& m_vm;
+    Vector<StackFrame>& m_results;
+    size_t m_remainingCapacityForFrameCapture;
+};
+
+void Interpreter::getStackTrace(Vector<StackFrame>& results, size_t maxStackSize)
+{
+    VM& vm = m_vm;
+    CallFrame* callFrame = vm.topCallFrame;
+    if (!callFrame)
+        return;
+
+    GetStackTraceFunctor functor(vm, results, maxStackSize);
+    callFrame->iterate(functor);
+}
+
+JSString* Interpreter::stackTraceAsString(ExecState* exec, Vector<StackFrame> stackTrace)
+{
+    // FIXME: JSStringJoiner could be more efficient than StringBuilder here.
+    StringBuilder builder;
+    for (unsigned i = 0; i < stackTrace.size(); i++) {
+        builder.append(String(stackTrace[i].toString(exec)));
+        if (i != stackTrace.size() - 1)
+            builder.append('\n');
+    }
+    return jsString(&exec->vm(), builder.toString());
+}
+
+class GetCatchHandlerFunctor {
+public:
+    GetCatchHandlerFunctor()
+        : m_handler(0)
+    {
     }
 
-    // If we throw in the middle of a call instruction, we need to notify
-    // the profiler manually that the call instruction has returned, since
-    // we'll never reach the relevant op_profile_did_call.
-    if (Profiler* profiler = *Profiler::enabledProfilerReference()) {
-#if !ENABLE(JIT)
-        if (isCallBytecode(codeBlock->instructions()[bytecodeOffset].u.opcode))
-            profiler->didExecute(callFrame, callFrame->r(codeBlock->instructions()[bytecodeOffset + 2].u.operand).jsValue());
-        else if (codeBlock->instructions().size() > (bytecodeOffset + 8) && codeBlock->instructions()[bytecodeOffset + 8].u.opcode == getOpcode(op_construct))
-            profiler->didExecute(callFrame, callFrame->r(codeBlock->instructions()[bytecodeOffset + 10].u.operand).jsValue());
-#else
-        int functionRegisterIndex;
-        if (codeBlock->functionRegisterForBytecodeOffset(bytecodeOffset, functionRegisterIndex))
-            profiler->didExecute(callFrame, callFrame->r(functionRegisterIndex).jsValue());
-#endif
+    HandlerInfo* handler() { return m_handler; }
+
+    StackVisitor::Status operator()(StackVisitor& visitor)
+    {
+        CodeBlock* codeBlock = visitor->codeBlock();
+        if (!codeBlock)
+            return StackVisitor::Continue;
+
+        unsigned bytecodeOffset = visitor->bytecodeOffset();
+        m_handler = codeBlock->handlerForBytecodeOffset(bytecodeOffset, CodeBlock::RequiredHandler::CatchHandler);
+        if (m_handler)
+            return StackVisitor::Done;
+
+        return StackVisitor::Continue;
+    }
+
+private:
+    HandlerInfo* m_handler;
+};
+
+class UnwindFunctor {
+public:
+    UnwindFunctor(VMEntryFrame*& vmEntryFrame, CallFrame*& callFrame, bool isTermination, CodeBlock*& codeBlock, HandlerInfo*& handler)
+        : m_vmEntryFrame(vmEntryFrame)
+        , m_callFrame(callFrame)
+        , m_isTermination(isTermination)
+        , m_codeBlock(codeBlock)
+        , m_handler(handler)
+    {
     }
 
-    // Calculate an exception handler vPC, unwinding call frames as necessary.
+    StackVisitor::Status operator()(StackVisitor& visitor)
+    {
+        VM& vm = m_callFrame->vm();
+        m_vmEntryFrame = visitor->vmEntryFrame();
+        m_callFrame = visitor->callFrame();
+        m_codeBlock = visitor->codeBlock();
+        unsigned bytecodeOffset = visitor->bytecodeOffset();
+
+        if (m_isTermination || !(m_handler = m_codeBlock ? m_codeBlock->handlerForBytecodeOffset(bytecodeOffset) : nullptr)) {
+            if (!unwindCallFrame(visitor)) {
+                if (LegacyProfiler* profiler = vm.enabledProfiler())
+                    profiler->exceptionUnwind(m_callFrame);
+                return StackVisitor::Done;
+            }
+        } else
+            return StackVisitor::Done;
 
-    HandlerInfo* handler = 0;
-    while (!(handler = codeBlock->handlerForBytecodeOffset(bytecodeOffset))) {
-        if (!unwindCallFrame(callFrame, exceptionValue, bytecodeOffset, codeBlock))
-            return 0;
+        return StackVisitor::Continue;
+    }
+
+private:
+    VMEntryFrame*& m_vmEntryFrame;
+    CallFrame*& m_callFrame;
+    bool m_isTermination;
+    CodeBlock*& m_codeBlock;
+    HandlerInfo*& m_handler;
+};
+
+NEVER_INLINE HandlerInfo* Interpreter::unwind(VMEntryFrame*& vmEntryFrame, CallFrame*& callFrame, Exception* exception)
+{
+    CodeBlock* codeBlock = callFrame->codeBlock();
+    bool isTermination = false;
+
+    JSValue exceptionValue = exception->value();
+    ASSERT(!exceptionValue.isEmpty());
+    ASSERT(!exceptionValue.isCell() || exceptionValue.asCell());
+    // This shouldn't be possible (hence the assertions), but we're already in the slowest of
+    // slow cases, so let's harden against it anyway to be safe.
+    if (exceptionValue.isEmpty() || (exceptionValue.isCell() && !exceptionValue.asCell()))
+        exceptionValue = jsNull();
+
+    if (exceptionValue.isObject())
+        isTermination = isTerminatedExecutionException(exception);
+
+    ASSERT(callFrame->vm().exception() && callFrame->vm().exception()->stack().size());
+
+    Debugger* debugger = callFrame->vmEntryGlobalObject()->debugger();
+    if (debugger && debugger->needsExceptionCallbacks() && !exception->didNotifyInspectorOfThrow()) {
+        // We need to clear the exception here in order to see if a new exception happens.
+        // Afterwards, the values are put back to continue processing this error.
+        SuspendExceptionScope scope(&callFrame->vm());
+        // This code assumes that if the debugger is enabled then there is no inlining.
+        // If that assumption turns out to be false then we'll ignore the inlined call
+        // frames.
+        // https://bugs.webkit.org/show_bug.cgi?id=121754
+
+        bool hasCatchHandler;
+        if (isTermination)
+            hasCatchHandler = false;
+        else {
+            GetCatchHandlerFunctor functor;
+            callFrame->iterate(functor);
+            HandlerInfo* handler = functor.handler();
+            ASSERT(!handler || handler->isCatchHandler());
+            hasCatchHandler = !!handler;
+        }
+
+        debugger->exception(callFrame, exceptionValue, hasCatchHandler);
+        ASSERT(!callFrame->hadException());
     }
+    exception->setDidNotifyInspectorOfThrow();
+
+    // Calculate an exception handler vPC, unwinding call frames as necessary.
+    HandlerInfo* handler = 0;
+    VM& vm = callFrame->vm();
+    ASSERT(callFrame == vm.topCallFrame);
+    UnwindFunctor functor(vmEntryFrame, callFrame, isTermination, codeBlock, handler);
+    callFrame->iterate(functor);
+    if (!handler)
+        return 0;
+
+    if (LegacyProfiler* profiler = vm.enabledProfiler())
+        profiler->exceptionUnwind(callFrame);
+
+    // Unwind the scope chain within the exception handler's call frame.
+    int targetScopeDepth = handler->scopeDepth;
+    if (codeBlock->needsActivation() && callFrame->hasActivation())
+        ++targetScopeDepth;
 
-    // Now unwind the scope chain within the exception handler's call frame.
+    int scopeRegisterOffset = codeBlock->scopeRegister().offset();
+    JSScope* scope = callFrame->scope(scopeRegisterOffset);
+    int scopeDelta = scope->depth() - targetScopeDepth;
+    RELEASE_ASSERT(scopeDelta >= 0);
 
-    ScopeChainNode* scopeChain = callFrame->scopeChain();
-    ScopeChain sc(scopeChain);
-    int scopeDelta = depth(codeBlock, sc) - handler->scopeDepth;
-    ASSERT(scopeDelta >= 0);
     while (scopeDelta--)
-        scopeChain = scopeChain->pop();
-    callFrame->setScopeChain(scopeChain);
+        scope = scope->next();
+
+    callFrame->setScope(scopeRegisterOffset, scope);
 
     return handler;
 }
 
-JSValue Interpreter::execute(ProgramExecutable* program, CallFrame* callFrame, ScopeChainNode* scopeChain, JSObject* thisObj, JSValue* exception)
+static inline JSValue checkedReturn(JSValue returnValue)
 {
-    ASSERT(!scopeChain->globalData->exception);
+    ASSERT(returnValue);
+    return returnValue;
+}
 
-    if (m_reentryDepth >= MaxSecondaryThreadReentryDepth) {
-        if (!isMainThread() || m_reentryDepth >= MaxMainThreadReentryDepth) {
-            *exception = createStackOverflowError(callFrame);
-            return jsNull();
-        }
+static inline JSObject* checkedReturn(JSObject* returnValue)
+{
+    ASSERT(returnValue);
+    return returnValue;
+}
+
+class SamplingScope {
+public:
+    SamplingScope(Interpreter* interpreter)
+        : m_interpreter(interpreter)
+    {
+        interpreter->startSampling();
+    }
+    ~SamplingScope()
+    {
+        m_interpreter->stopSampling();
     }
+private:
+    Interpreter* m_interpreter;
+};
+
+JSValue Interpreter::execute(ProgramExecutable* program, CallFrame* callFrame, JSObject* thisObj)
+{
+    SamplingScope samplingScope(this);
 
-    CodeBlock* codeBlock = &program->bytecode(callFrame, scopeChain);
+    JSScope* scope = thisObj->globalObject();
+    VM& vm = *scope->vm();
 
-    Register* oldEnd = m_registerFile.end();
-    Register* newEnd = oldEnd + codeBlock->m_numParameters + RegisterFile::CallFrameHeaderSize + codeBlock->m_numCalleeRegisters;
-    if (!m_registerFile.grow(newEnd)) {
-        *exception = createStackOverflowError(callFrame);
+    ASSERT(!vm.exception());
+    ASSERT(!vm.isCollectorBusy());
+    RELEASE_ASSERT(vm.currentThreadIsHoldingAPILock());
+    if (vm.isCollectorBusy())
         return jsNull();
+
+    if (!vm.isSafeToRecurse())
+        return checkedReturn(throwStackOverflowError(callFrame));
+
+    // First check if the "program" is actually just a JSON object. If so,
+    // we'll handle the JSON object here. Else, we'll handle real JS code
+    // below at failedJSONP.
+
+    Vector<JSONPData> JSONPData;
+    bool parseResult;
+    const String programSource = program->source().toString();
+    if (programSource.isNull())
+        return jsUndefined();
+    if (programSource.is8Bit()) {
+        LiteralParser<LChar> literalParser(callFrame, programSource.characters8(), programSource.length(), JSONP);
+        parseResult = literalParser.tryJSONPParse(JSONPData, scope->globalObject()->globalObjectMethodTable()->supportsRichSourceInfo(scope->globalObject()));
+    } else {
+        LiteralParser<UChar> literalParser(callFrame, programSource.characters16(), programSource.length(), JSONP);
+        parseResult = literalParser.tryJSONPParse(JSONPData, scope->globalObject()->globalObjectMethodTable()->supportsRichSourceInfo(scope->globalObject()));
+    }
+
+    if (parseResult) {
+        JSGlobalObject* globalObject = scope->globalObject();
+        JSValue result;
+        for (unsigned entry = 0; entry < JSONPData.size(); entry++) {
+            Vector<JSONPPathEntry> JSONPPath;
+            JSONPPath.swap(JSONPData[entry].m_path);
+            JSValue JSONPValue = JSONPData[entry].m_value.get();
+            if (JSONPPath.size() == 1 && JSONPPath[0].m_type == JSONPPathEntryTypeDeclare) {
+                globalObject->addVar(callFrame, JSONPPath[0].m_pathEntryName);
+                PutPropertySlot slot(globalObject);
+                globalObject->methodTable()->put(globalObject, callFrame, JSONPPath[0].m_pathEntryName, JSONPValue, slot);
+                result = jsUndefined();
+                continue;
+            }
+            JSValue baseObject(globalObject);
+            for (unsigned i = 0; i < JSONPPath.size() - 1; i++) {
+                ASSERT(JSONPPath[i].m_type != JSONPPathEntryTypeDeclare);
+                switch (JSONPPath[i].m_type) {
+                case JSONPPathEntryTypeDot: {
+                    if (i == 0) {
+                        PropertySlot slot(globalObject);
+                        if (!globalObject->getPropertySlot(callFrame, JSONPPath[i].m_pathEntryName, slot)) {
+                            if (entry)
+                                return callFrame->vm().throwException(callFrame, createUndefinedVariableError(callFrame, JSONPPath[i].m_pathEntryName));
+                            goto failedJSONP;
+                        }
+                        baseObject = slot.getValue(callFrame, JSONPPath[i].m_pathEntryName);
+                    } else
+                        baseObject = baseObject.get(callFrame, JSONPPath[i].m_pathEntryName);
+                    if (callFrame->hadException())
+                        return jsUndefined();
+                    continue;
+                }
+                case JSONPPathEntryTypeLookup: {
+                    baseObject = baseObject.get(callFrame, JSONPPath[i].m_pathIndex);
+                    if (callFrame->hadException())
+                        return jsUndefined();
+                    continue;
+                }
+                default:
+                    RELEASE_ASSERT_NOT_REACHED();
+                    return jsUndefined();
+                }
+            }
+            PutPropertySlot slot(baseObject);
+            switch (JSONPPath.last().m_type) {
+            case JSONPPathEntryTypeCall: {
+                JSValue function = baseObject.get(callFrame, JSONPPath.last().m_pathEntryName);
+                if (callFrame->hadException())
+                    return jsUndefined();
+                CallData callData;
+                CallType callType = getCallData(function, callData);
+                if (callType == CallTypeNone)
+                    return callFrame->vm().throwException(callFrame, createNotAFunctionError(callFrame, function));
+                MarkedArgumentBuffer jsonArg;
+                jsonArg.append(JSONPValue);
+                JSValue thisValue = JSONPPath.size() == 1 ? jsUndefined(): baseObject;
+                JSONPValue = JSC::call(callFrame, function, callType, callData, thisValue, jsonArg);
+                if (callFrame->hadException())
+                    return jsUndefined();
+                break;
+            }
+            case JSONPPathEntryTypeDot: {
+                baseObject.put(callFrame, JSONPPath.last().m_pathEntryName, JSONPValue, slot);
+                if (callFrame->hadException())
+                    return jsUndefined();
+                break;
+            }
+            case JSONPPathEntryTypeLookup: {
+                baseObject.putByIndex(callFrame, JSONPPath.last().m_pathIndex, JSONPValue, slot.isStrictMode());
+                if (callFrame->hadException())
+                    return jsUndefined();
+                break;
+            }
+            default:
+                RELEASE_ASSERT_NOT_REACHED();
+                    return jsUndefined();
+            }
+            result = JSONPValue;
+        }
+        return result;
     }
+failedJSONP:
+    // If we get here, then we have already proven that the script is not a JSON
+    // object.
 
-    DynamicGlobalObjectScope globalObjectScope(callFrame, scopeChain->globalObject);
+    VMEntryScope entryScope(vm, scope->globalObject());
 
-    JSGlobalObject* lastGlobalObject = m_registerFile.globalObject();
-    JSGlobalObject* globalObject = callFrame->dynamicGlobalObject();
-    globalObject->copyGlobalsTo(m_registerFile);
+    // Compile source to bytecode if necessary:
+    if (JSObject* error = program->initializeGlobalProperties(vm, callFrame, scope))
+        return checkedReturn(callFrame->vm().throwException(callFrame, error));
 
-    CallFrame* newCallFrame = CallFrame::create(oldEnd + codeBlock->m_numParameters + RegisterFile::CallFrameHeaderSize);
-    newCallFrame->r(codeBlock->thisRegister()) = JSValue(thisObj);
-    newCallFrame->init(codeBlock, 0, scopeChain, CallFrame::noCaller(), 0, 0, 0);
+    if (JSObject* error = program->prepareForExecution(callFrame, nullptr, scope, CodeForCall))
+        return checkedReturn(callFrame->vm().throwException(callFrame, error));
 
-    if (codeBlock->needsFullScopeChain())
-        scopeChain->ref();
+    ProgramCodeBlock* codeBlock = program->codeBlock();
 
-    Profiler** profiler = Profiler::enabledProfilerReference();
-    if (*profiler)
-        (*profiler)->willExecute(newCallFrame, program->sourceURL(), program->lineNo());
+    if (UNLIKELY(vm.watchdog && vm.watchdog->didFire(callFrame)))
+        return throwTerminatedExecutionException(callFrame);
 
+    ASSERT(codeBlock->numParameters() == 1); // 1 parameter for 'this'.
+
+    ProtoCallFrame protoCallFrame;
+    protoCallFrame.init(codeBlock, JSCallee::create(vm, scope->globalObject(), scope), thisObj, 1);
+
+    if (LegacyProfiler* profiler = vm.enabledProfiler())
+        profiler->willExecute(callFrame, program->sourceURL(), program->firstLine(), program->startColumn());
+
+    // Execute the code:
     JSValue result;
     {
         SamplingTool::CallRecord callRecord(m_sampler.get());
+        Watchdog::Scope watchdogScope(vm.watchdog.get());
 
-        m_reentryDepth++;
-#if ENABLE(JIT)
-        result = program->jitCode(newCallFrame, scopeChain).execute(&m_registerFile, newCallFrame, scopeChain->globalData, exception);
-#else
-        result = privateExecute(Normal, &m_registerFile, newCallFrame, exception);
-#endif
-        m_reentryDepth--;
+        result = program->generatedJITCode()->execute(&vm, &protoCallFrame);
     }
 
-    if (*profiler)
-        (*profiler)->didExecute(callFrame, program->sourceURL(), program->lineNo());
-
-    if (m_reentryDepth && lastGlobalObject && globalObject != lastGlobalObject)
-        lastGlobalObject->copyGlobalsTo(m_registerFile);
-
-    m_registerFile.shrink(oldEnd);
+    if (LegacyProfiler* profiler = vm.enabledProfiler())
+        profiler->didExecute(callFrame, program->sourceURL(), program->firstLine(), program->startColumn());
 
-    return result;
+    return checkedReturn(result);
 }
 
-JSValue Interpreter::execute(FunctionExecutable* functionExecutable, CallFrame* callFrame, JSFunction* function, JSObject* thisObj, const ArgList& args, ScopeChainNode* scopeChain, JSValue* exception)
+JSValue Interpreter::executeCall(CallFrame* callFrame, JSObject* function, CallType callType, const CallData& callData, JSValue thisValue, const ArgList& args)
 {
-    ASSERT(!scopeChain->globalData->exception);
+    VM& vm = callFrame->vm();
+    ASSERT(!callFrame->hadException());
+    ASSERT(!vm.isCollectorBusy());
+    if (vm.isCollectorBusy())
+        return jsNull();
 
-    if (m_reentryDepth >= MaxSecondaryThreadReentryDepth) {
-        if (!isMainThread() || m_reentryDepth >= MaxMainThreadReentryDepth) {
-            *exception = createStackOverflowError(callFrame);
-            return jsNull();
-        }
-    }
+    bool isJSCall = (callType == CallTypeJS);
+    JSScope* scope = nullptr;
+    CodeBlock* newCodeBlock;
+    size_t argsCount = 1 + args.size(); // implicit "this" parameter
 
-    Register* oldEnd = m_registerFile.end();
-    int argc = 1 + args.size(); // implicit "this" parameter
+    JSGlobalObject* globalObject;
 
-    if (!m_registerFile.grow(oldEnd + argc)) {
-        *exception = createStackOverflowError(callFrame);
-        return jsNull();
+    if (isJSCall) {
+        scope = callData.js.scope;
+        globalObject = scope->globalObject();
+    } else {
+        ASSERT(callType == CallTypeHost);
+        globalObject = function->globalObject();
     }
 
-    DynamicGlobalObjectScope globalObjectScope(callFrame, scopeChain->globalObject);
+    VMEntryScope entryScope(vm, globalObject);
+    if (!vm.isSafeToRecurse())
+        return checkedReturn(throwStackOverflowError(callFrame));
 
-    CallFrame* newCallFrame = CallFrame::create(oldEnd);
-    size_t dst = 0;
-    newCallFrame->r(0) = JSValue(thisObj);
-    ArgList::const_iterator end = args.end();
-    for (ArgList::const_iterator it = args.begin(); it != end; ++it)
-        newCallFrame->r(++dst) = *it;
+    if (isJSCall) {
+        // Compile the callee:
+        JSObject* compileError = callData.js.functionExecutable->prepareForExecution(callFrame, jsCast<JSFunction*>(function), scope, CodeForCall);
+        if (UNLIKELY(!!compileError)) {
+            return checkedReturn(callFrame->vm().throwException(callFrame, compileError));
+        }
+        newCodeBlock = callData.js.functionExecutable->codeBlockForCall();
+        ASSERT(!!newCodeBlock);
+        newCodeBlock->m_shouldAlwaysBeInlined = false;
+    } else
+        newCodeBlock = 0;
 
-    CodeBlock* codeBlock = &functionExecutable->bytecode(callFrame, scopeChain);
-    newCallFrame = slideRegisterWindowForCall(codeBlock, &m_registerFile, newCallFrame, argc + RegisterFile::CallFrameHeaderSize, argc);
-    if (UNLIKELY(!newCallFrame)) {
-        *exception = createStackOverflowError(callFrame);
-        m_registerFile.shrink(oldEnd);
-        return jsNull();
-    }
-    // a 0 codeBlock indicates a built-in caller
-    newCallFrame->init(codeBlock, 0, scopeChain, callFrame->addHostCallFrameFlag(), 0, argc, function);
+    if (UNLIKELY(vm.watchdog && vm.watchdog->didFire(callFrame)))
+        return throwTerminatedExecutionException(callFrame);
 
-    Profiler** profiler = Profiler::enabledProfilerReference();
-    if (*profiler)
-        (*profiler)->willExecute(callFrame, function);
+    ProtoCallFrame protoCallFrame;
+    protoCallFrame.init(newCodeBlock, function, thisValue, argsCount, args.data());
+
+    if (LegacyProfiler* profiler = vm.enabledProfiler())
+        profiler->willExecute(callFrame, function);
 
     JSValue result;
     {
-        SamplingTool::CallRecord callRecord(m_sampler.get());
+        SamplingTool::CallRecord callRecord(m_sampler.get(), !isJSCall);
+        Watchdog::Scope watchdogScope(vm.watchdog.get());
 
-        m_reentryDepth++;
-#if ENABLE(JIT)
-        result = functionExecutable->jitCode(newCallFrame, scopeChain).execute(&m_registerFile, newCallFrame, scopeChain->globalData, exception);
-#else
-        result = privateExecute(Normal, &m_registerFile, newCallFrame, exception);
-#endif
-        m_reentryDepth--;
+        // Execute the code:
+        if (isJSCall)
+            result = callData.js.functionExecutable->generatedJITCodeForCall()->execute(&vm, &protoCallFrame);
+        else {
+            result = JSValue::decode(vmEntryToNative(reinterpret_cast<void*>(callData.native.function), &vm, &protoCallFrame));
+            if (callFrame->hadException())
+                result = jsNull();
+        }
     }
 
-    if (*profiler)
-        (*profiler)->didExecute(callFrame, function);
+    if (LegacyProfiler* profiler = vm.enabledProfiler())
+        profiler->didExecute(callFrame, function);
 
-    m_registerFile.shrink(oldEnd);
-    return result;
+    return checkedReturn(result);
 }
 
-CallFrameClosure Interpreter::prepareForRepeatCall(FunctionExecutable* FunctionExecutable, CallFrame* callFrame, JSFunction* function, int argCount, ScopeChainNode* scopeChain, JSValue* exception)
+JSObject* Interpreter::executeConstruct(CallFrame* callFrame, JSObject* constructor, ConstructType constructType, const ConstructData& constructData, const ArgList& args)
 {
-    ASSERT(!scopeChain->globalData->exception);
-    
-    if (m_reentryDepth >= MaxSecondaryThreadReentryDepth) {
-        if (!isMainThread() || m_reentryDepth >= MaxMainThreadReentryDepth) {
-            *exception = createStackOverflowError(callFrame);
-            return CallFrameClosure();
+    VM& vm = callFrame->vm();
+    ASSERT(!callFrame->hadException());
+    ASSERT(!vm.isCollectorBusy());
+    // We throw in this case because we have to return something "valid" but we're
+    // already in an invalid state.
+    if (vm.isCollectorBusy())
+        return checkedReturn(throwStackOverflowError(callFrame));
+
+    bool isJSConstruct = (constructType == ConstructTypeJS);
+    JSScope* scope = nullptr;
+    CodeBlock* newCodeBlock;
+    size_t argsCount = 1 + args.size(); // implicit "this" parameter
+
+    JSGlobalObject* globalObject;
+
+    if (isJSConstruct) {
+        scope = constructData.js.scope;
+        globalObject = scope->globalObject();
+    } else {
+        ASSERT(constructType == ConstructTypeHost);
+        globalObject = constructor->globalObject();
+    }
+
+    VMEntryScope entryScope(vm, globalObject);
+    if (!vm.isSafeToRecurse())
+        return checkedReturn(throwStackOverflowError(callFrame));
+
+    if (isJSConstruct) {
+        // Compile the callee:
+        JSObject* compileError = constructData.js.functionExecutable->prepareForExecution(callFrame, jsCast<JSFunction*>(constructor), scope, CodeForConstruct);
+        if (UNLIKELY(!!compileError)) {
+            return checkedReturn(callFrame->vm().throwException(callFrame, compileError));
+        }
+        newCodeBlock = constructData.js.functionExecutable->codeBlockForConstruct();
+        ASSERT(!!newCodeBlock);
+        newCodeBlock->m_shouldAlwaysBeInlined = false;
+    } else
+        newCodeBlock = 0;
+
+    if (UNLIKELY(vm.watchdog && vm.watchdog->didFire(callFrame)))
+        return throwTerminatedExecutionException(callFrame);
+
+    ProtoCallFrame protoCallFrame;
+    protoCallFrame.init(newCodeBlock, constructor, constructor, argsCount, args.data());
+
+    if (LegacyProfiler* profiler = vm.enabledProfiler())
+        profiler->willExecute(callFrame, constructor);
+
+    JSValue result;
+    {
+        SamplingTool::CallRecord callRecord(m_sampler.get(), !isJSConstruct);
+        Watchdog::Scope watchdogScope(vm.watchdog.get());
+
+        // Execute the code.
+        if (isJSConstruct)
+            result = constructData.js.functionExecutable->generatedJITCodeForConstruct()->execute(&vm, &protoCallFrame);
+        else {
+            result = JSValue::decode(vmEntryToNative(reinterpret_cast<void*>(constructData.native.function), &vm, &protoCallFrame));
+
+            if (!callFrame->hadException())
+                RELEASE_ASSERT(result.isObject());
         }
     }
+
+    if (LegacyProfiler* profiler = vm.enabledProfiler())
+        profiler->didExecute(callFrame, constructor);
+
+    if (callFrame->hadException())
+        return 0;
+    ASSERT(result.isObject());
+    return checkedReturn(asObject(result));
+}
+
+CallFrameClosure Interpreter::prepareForRepeatCall(FunctionExecutable* functionExecutable, CallFrame* callFrame, ProtoCallFrame* protoCallFrame, JSFunction* function, int argumentCountIncludingThis, JSScope* scope, JSValue* args)
+{
+    VM& vm = *scope->vm();
+    ASSERT(!vm.exception());
     
-    Register* oldEnd = m_registerFile.end();
-    int argc = 1 + argCount; // implicit "this" parameter
-    
-    if (!m_registerFile.grow(oldEnd + argc)) {
-        *exception = createStackOverflowError(callFrame);
+    if (vm.isCollectorBusy())
         return CallFrameClosure();
-    }
 
-    CallFrame* newCallFrame = CallFrame::create(oldEnd);
-    size_t dst = 0;
-    for (int i = 0; i < argc; ++i)
-        newCallFrame->r(++dst) = jsUndefined();
-    
-    CodeBlock* codeBlock = &FunctionExecutable->bytecode(callFrame, scopeChain);
-    newCallFrame = slideRegisterWindowForCall(codeBlock, &m_registerFile, newCallFrame, argc + RegisterFile::CallFrameHeaderSize, argc);
-    if (UNLIKELY(!newCallFrame)) {
-        *exception = createStackOverflowError(callFrame);
-        m_registerFile.shrink(oldEnd);
+    // Compile the callee:
+    JSObject* error = functionExecutable->prepareForExecution(callFrame, function, scope, CodeForCall);
+    if (error) {
+        callFrame->vm().throwException(callFrame, error);
         return CallFrameClosure();
     }
-    // a 0 codeBlock indicates a built-in caller
-    newCallFrame->init(codeBlock, 0, scopeChain, callFrame->addHostCallFrameFlag(), 0, argc, function);
-#if ENABLE(JIT)
-    FunctionExecutable->jitCode(newCallFrame, scopeChain);
-#endif
+    CodeBlock* newCodeBlock = functionExecutable->codeBlockForCall();
+    newCodeBlock->m_shouldAlwaysBeInlined = false;
 
-    CallFrameClosure result = { callFrame, newCallFrame, function, FunctionExecutable, scopeChain->globalData, oldEnd, scopeChain, codeBlock->m_numParameters, argc };
+    size_t argsCount = argumentCountIncludingThis;
+
+    protoCallFrame->init(newCodeBlock, function, jsUndefined(), argsCount, args);
+    // Return the successful closure:
+    CallFrameClosure result = { callFrame, protoCallFrame, function, functionExecutable, &vm, scope, newCodeBlock->numParameters(), argumentCountIncludingThis };
     return result;
 }
 
-JSValue Interpreter::execute(CallFrameClosure& closure, JSValue* exception
+JSValue Interpreter::execute(CallFrameClosure& closure) 
 {
-    closure.resetCallFrame();
-    Profiler** profiler = Profiler::enabledProfilerReference();
-    if (*profiler)
-        (*profiler)->willExecute(closure.oldCallFrame, closure.function);
+    VM& vm = *closure.vm;
+    SamplingScope samplingScope(this);
     
+    ASSERT(!vm.isCollectorBusy());
+    RELEASE_ASSERT(vm.currentThreadIsHoldingAPILock());
+    if (vm.isCollectorBusy())
+        return jsNull();
+
+    StackStats::CheckPoint stackCheckPoint;
+
+    if (LegacyProfiler* profiler = vm.enabledProfiler())
+        profiler->willExecute(closure.oldCallFrame, closure.function);
+
+    if (UNLIKELY(vm.watchdog && vm.watchdog->didFire(closure.oldCallFrame)))
+        return throwTerminatedExecutionException(closure.oldCallFrame);
+
+    // Execute the code:
     JSValue result;
     {
         SamplingTool::CallRecord callRecord(m_sampler.get());
-        
-        m_reentryDepth++;
-#if ENABLE(JIT)
-        result = closure.functionExecutable->generatedJITCode().execute(&m_registerFile, closure.newCallFrame, closure.globalData, exception);
-#else
-        result = privateExecute(Normal, &m_registerFile, closure.newCallFrame, exception);
-#endif
-        m_reentryDepth--;
+        Watchdog::Scope watchdogScope(vm.watchdog.get());
+
+        result = closure.functionExecutable->generatedJITCodeForCall()->execute(&vm, closure.protoCallFrame);
     }
-    
-    if (*profiler)
-        (*profiler)->didExecute(closure.oldCallFrame, closure.function);
-    return result;
-}
 
-void Interpreter::endRepeatCall(CallFrameClosure& closure)
-{
-    m_registerFile.shrink(closure.oldEnd);
-}
+    if (LegacyProfiler* profiler = vm.enabledProfiler())
+        profiler->didExecute(closure.oldCallFrame, closure.function);
 
-JSValue Interpreter::execute(EvalExecutable* eval, CallFrame* callFrame, JSObject* thisObj, ScopeChainNode* scopeChain, JSValue* exception)
-{
-    return execute(eval, callFrame, thisObj, m_registerFile.size() + eval->bytecode(callFrame, scopeChain).m_numParameters + RegisterFile::CallFrameHeaderSize, scopeChain, exception);
+    return checkedReturn(result);
 }
 
-JSValue Interpreter::execute(EvalExecutable* eval, CallFrame* callFrame, JSObject* thisObj, int globalRegisterOffset, ScopeChainNode* scopeChain, JSValue* exception)
+JSValue Interpreter::execute(EvalExecutable* eval, CallFrame* callFrame, JSValue thisValue, JSScope* scope)
 {
-    ASSERT(!scopeChain->globalData->exception);
-
-    if (m_reentryDepth >= MaxSecondaryThreadReentryDepth) {
-        if (!isMainThread() || m_reentryDepth >= MaxMainThreadReentryDepth) {
-            *exception = createStackOverflowError(callFrame);
-            return jsNull();
-        }
-    }
-
-    DynamicGlobalObjectScope globalObjectScope(callFrame, scopeChain->globalObject);
-
-    EvalCodeBlock* codeBlock = &eval->bytecode(callFrame, scopeChain);
+    VM& vm = *scope->vm();
+    SamplingScope samplingScope(this);
+    
+    ASSERT(scope->vm() == &callFrame->vm());
+    ASSERT(!vm.exception());
+    ASSERT(!vm.isCollectorBusy());
+    RELEASE_ASSERT(vm.currentThreadIsHoldingAPILock());
+    if (vm.isCollectorBusy())
+        return jsNull();
 
-    JSVariableObject* variableObject;
-    for (ScopeChainNode* node = scopeChain; ; node = node->next) {
-        ASSERT(node);
-        if (node->object->isVariableObject()) {
-            variableObject = static_cast<JSVariableObject*>(node->object);
-            break;
+    VMEntryScope entryScope(vm, scope->globalObject());
+    if (!vm.isSafeToRecurse())
+        return checkedReturn(throwStackOverflowError(callFrame));        
+
+    unsigned numVariables = eval->numVariables();
+    int numFunctions = eval->numberOfFunctionDecls();
+
+    JSScope* variableObject;
+    if ((numVariables || numFunctions) && eval->isStrictMode()) {
+        scope = StrictEvalActivation::create(callFrame, scope);
+        variableObject = scope;
+    } else {
+        for (JSScope* node = scope; ; node = node->next()) {
+            RELEASE_ASSERT(node);
+            if (node->isVariableObject()) {
+                ASSERT(!node->isNameScopeObject());
+                variableObject = node;
+                break;
+            }
         }
     }
 
-    { // Scope for BatchedTransitionOptimizer
+    JSObject* compileError = eval->prepareForExecution(callFrame, nullptr, scope, CodeForCall);
+    if (UNLIKELY(!!compileError))
+        return checkedReturn(callFrame->vm().throwException(callFrame, compileError));
+    EvalCodeBlock* codeBlock = eval->codeBlock();
 
-        BatchedTransitionOptimizer optimizer(variableObject);
+    if (numVariables || numFunctions) {
+        BatchedTransitionOptimizer optimizer(vm, variableObject);
+        if (variableObject->next())
+            variableObject->globalObject()->varInjectionWatchpoint()->fireAll("Executed eval, fired VarInjection watchpoint");
 
-        unsigned numVariables = codeBlock->numVariables();
         for (unsigned i = 0; i < numVariables; ++i) {
             const Identifier& ident = codeBlock->variable(i);
             if (!variableObject->hasProperty(callFrame, ident)) {
-                PutPropertySlot slot;
-                variableObject->put(callFrame, ident, jsUndefined(), slot);
+                PutPropertySlot slot(variableObject);
+                variableObject->methodTable()->put(variableObject, callFrame, ident, jsUndefined(), slot);
             }
         }
 
-        int numFunctions = codeBlock->numberOfFunctionDecls();
         for (int i = 0; i < numFunctions; ++i) {
             FunctionExecutable* function = codeBlock->functionDecl(i);
-            PutPropertySlot slot;
-            variableObject->put(callFrame, function->name(), function->make(callFrame, scopeChain), slot);
+            PutPropertySlot slot(variableObject);
+            variableObject->methodTable()->put(variableObject, callFrame, function->name(), JSFunction::create(vm, function, scope), slot);
         }
-
-    }
-
-    Register* oldEnd = m_registerFile.end();
-    Register* newEnd = m_registerFile.start() + globalRegisterOffset + codeBlock->m_numCalleeRegisters;
-    if (!m_registerFile.grow(newEnd)) {
-        *exception = createStackOverflowError(callFrame);
-        return jsNull();
     }
 
-    CallFrame* newCallFrame = CallFrame::create(m_registerFile.start() + globalRegisterOffset);
+    if (UNLIKELY(vm.watchdog && vm.watchdog->didFire(callFrame)))
+        return throwTerminatedExecutionException(callFrame);
 
-    // a 0 codeBlock indicates a built-in caller
-    newCallFrame->r(codeBlock->thisRegister()) = JSValue(thisObj);
-    newCallFrame->init(codeBlock, 0, scopeChain, callFrame->addHostCallFrameFlag(), 0, 0, 0);
+    ASSERT(codeBlock->numParameters() == 1); // 1 parameter for 'this'.
 
-    if (codeBlock->needsFullScopeChain())
-        scopeChain->ref();
+    ProtoCallFrame protoCallFrame;
+    protoCallFrame.init(codeBlock, JSCallee::create(vm, scope->globalObject(), scope), thisValue, 1);
 
-    Profiler** profiler = Profiler::enabledProfilerReference();
-    if (*profiler)
-        (*profiler)->willExecute(newCallFrame, eval->sourceURL(), eval->lineNo());
+    if (LegacyProfiler* profiler = vm.enabledProfiler())
+        profiler->willExecute(callFrame, eval->sourceURL(), eval->firstLine(), eval->startColumn());
 
+    // Execute the code:
     JSValue result;
     {
         SamplingTool::CallRecord callRecord(m_sampler.get());
+        Watchdog::Scope watchdogScope(vm.watchdog.get());
 
-        m_reentryDepth++;
-#if ENABLE(JIT)
-        result = eval->jitCode(newCallFrame, scopeChain).execute(&m_registerFile, newCallFrame, scopeChain->globalData, exception);
-#else
-        result = privateExecute(Normal, &m_registerFile, newCallFrame, exception);
-#endif
-        m_reentryDepth--;
+        result = eval->generatedJITCode()->execute(&vm, &protoCallFrame);
     }
 
-    if (*profiler)
-        (*profiler)->didExecute(callFrame, eval->sourceURL(), eval->lineNo());
+    if (LegacyProfiler* profiler = vm.enabledProfiler())
+        profiler->didExecute(callFrame, eval->sourceURL(), eval->firstLine(), eval->startColumn());
 
-    m_registerFile.shrink(oldEnd);
-    return result;
+    return checkedReturn(result);
 }
 
-NEVER_INLINE void Interpreter::debug(CallFrame* callFrame, DebugHookID debugHookID, int firstLine, int lastLine)
+NEVER_INLINE void Interpreter::debug(CallFrame* callFrame, DebugHookID debugHookID)
 {
-    Debugger* debugger = callFrame->dynamicGlobalObject()->debugger();
+    Debugger* debugger = callFrame->vmEntryGlobalObject()->debugger();
     if (!debugger)
         return;
 
+    ASSERT(callFrame->codeBlock()->hasDebuggerRequests());
+    ASSERT(!callFrame->hadException());
+
     switch (debugHookID) {
         case DidEnterCallFrame:
-            debugger->callEvent(callFrame, callFrame->codeBlock()->ownerExecutable()->sourceID(), firstLine);
-            return;
+            debugger->callEvent(callFrame);
+            break;
         case WillLeaveCallFrame:
-            debugger->returnEvent(callFrame, callFrame->codeBlock()->ownerExecutable()->sourceID(), lastLine);
-            return;
+            debugger->returnEvent(callFrame);
+            break;
         case WillExecuteStatement:
-            debugger->atStatement(callFrame, callFrame->codeBlock()->ownerExecutable()->sourceID(), firstLine);
-            return;
+            debugger->atStatement(callFrame);
+            break;
         case WillExecuteProgram:
-            debugger->willExecuteProgram(callFrame, callFrame->codeBlock()->ownerExecutable()->sourceID(), firstLine);
-            return;
+            debugger->willExecuteProgram(callFrame);
+            break;
         case DidExecuteProgram:
-            debugger->didExecuteProgram(callFrame, callFrame->codeBlock()->ownerExecutable()->sourceID(), lastLine);
-            return;
+            debugger->didExecuteProgram(callFrame);
+            break;
         case DidReachBreakpoint:
-            debugger->didReachBreakpoint(callFrame, callFrame->codeBlock()->ownerExecutable()->sourceID(), lastLine);
-            return;
-    }
-}
-    
-#if USE(INTERPRETER)
-NEVER_INLINE ScopeChainNode* Interpreter::createExceptionScope(CallFrame* callFrame, const Instruction* vPC)
-{
-    int dst = vPC[1].u.operand;
-    CodeBlock* codeBlock = callFrame->codeBlock();
-    Identifier& property = codeBlock->identifier(vPC[2].u.operand);
-    JSValue value = callFrame->r(vPC[3].u.operand).jsValue();
-    JSObject* scope = new (callFrame) JSStaticScopeObject(callFrame, property, value, DontDelete);
-    callFrame->r(dst) = JSValue(scope);
-
-    return callFrame->scopeChain()->push(scope);
-}
-
-NEVER_INLINE void Interpreter::tryCachePutByID(CallFrame* callFrame, CodeBlock* codeBlock, Instruction* vPC, JSValue baseValue, const PutPropertySlot& slot)
-{
-    // Recursive invocation may already have specialized this instruction.
-    if (vPC[0].u.opcode != getOpcode(op_put_by_id))
-        return;
-
-    if (!baseValue.isCell())
-        return;
-
-    // Uncacheable: give up.
-    if (!slot.isCacheable()) {
-        vPC[0] = getOpcode(op_put_by_id_generic);
-        return;
-    }
-    
-    JSCell* baseCell = asCell(baseValue);
-    Structure* structure = baseCell->structure();
-
-    if (structure->isUncacheableDictionary()) {
-        vPC[0] = getOpcode(op_put_by_id_generic);
-        return;
-    }
-
-    // Cache miss: record Structure to compare against next time.
-    Structure* lastStructure = vPC[4].u.structure;
-    if (structure != lastStructure) {
-        // First miss: record Structure to compare against next time.
-        if (!lastStructure) {
-            vPC[4] = structure;
-            return;
-        }
-
-        // Second miss: give up.
-        vPC[0] = getOpcode(op_put_by_id_generic);
-        return;
-    }
-
-    // Cache hit: Specialize instruction and ref Structures.
-
-    // If baseCell != slot.base(), then baseCell must be a proxy for another object.
-    if (baseCell != slot.base()) {
-        vPC[0] = getOpcode(op_put_by_id_generic);
-        return;
-    }
-
-    // Structure transition, cache transition info
-    if (slot.type() == PutPropertySlot::NewProperty) {
-        if (structure->isDictionary()) {
-            vPC[0] = getOpcode(op_put_by_id_generic);
-            return;
-        }
-
-        // put_by_id_transition checks the prototype chain for setters.
-        normalizePrototypeChain(callFrame, baseCell);
-
-        vPC[0] = getOpcode(op_put_by_id_transition);
-        vPC[4] = structure->previousID();
-        vPC[5] = structure;
-        vPC[6] = structure->prototypeChain(callFrame);
-        vPC[7] = slot.cachedOffset();
-        codeBlock->refStructures(vPC);
-        return;
-    }
-
-    vPC[0] = getOpcode(op_put_by_id_replace);
-    vPC[5] = slot.cachedOffset();
-    codeBlock->refStructures(vPC);
-}
-
-NEVER_INLINE void Interpreter::uncachePutByID(CodeBlock* codeBlock, Instruction* vPC)
-{
-    codeBlock->derefStructures(vPC);
-    vPC[0] = getOpcode(op_put_by_id);
-    vPC[4] = 0;
-}
-
-NEVER_INLINE void Interpreter::tryCacheGetByID(CallFrame* callFrame, CodeBlock* codeBlock, Instruction* vPC, JSValue baseValue, const Identifier& propertyName, const PropertySlot& slot)
-{
-    // Recursive invocation may already have specialized this instruction.
-    if (vPC[0].u.opcode != getOpcode(op_get_by_id))
-        return;
-
-    // FIXME: Cache property access for immediates.
-    if (!baseValue.isCell()) {
-        vPC[0] = getOpcode(op_get_by_id_generic);
-        return;
-    }
-
-    JSGlobalData* globalData = &callFrame->globalData();
-    if (isJSArray(globalData, baseValue) && propertyName == callFrame->propertyNames().length) {
-        vPC[0] = getOpcode(op_get_array_length);
-        return;
-    }
-
-    if (isJSString(globalData, baseValue) && propertyName == callFrame->propertyNames().length) {
-        vPC[0] = getOpcode(op_get_string_length);
-        return;
-    }
-
-    // Uncacheable: give up.
-    if (!slot.isCacheable()) {
-        vPC[0] = getOpcode(op_get_by_id_generic);
-        return;
-    }
-
-    Structure* structure = asCell(baseValue)->structure();
-
-    if (structure->isUncacheableDictionary()) {
-        vPC[0] = getOpcode(op_get_by_id_generic);
-        return;
-    }
-
-    // Cache miss
-    Structure* lastStructure = vPC[4].u.structure;
-    if (structure != lastStructure) {
-        // First miss: record Structure to compare against next time.
-        if (!lastStructure) {
-            vPC[4] = structure;
-            return;
-        }
-
-        // Second miss: give up.
-        vPC[0] = getOpcode(op_get_by_id_generic);
-        return;
-    }
-
-    // Cache hit: Specialize instruction and ref Structures.
-
-    if (slot.slotBase() == baseValue) {
-        vPC[0] = getOpcode(op_get_by_id_self);
-        vPC[5] = slot.cachedOffset();
-
-        codeBlock->refStructures(vPC);
-        return;
-    }
-
-    if (structure->isDictionary()) {
-        vPC[0] = getOpcode(op_get_by_id_generic);
-        return;
-    }
-
-    if (slot.slotBase() == structure->prototypeForLookup(callFrame)) {
-        ASSERT(slot.slotBase().isObject());
-
-        JSObject* baseObject = asObject(slot.slotBase());
-        size_t offset = slot.cachedOffset();
-
-        // Since we're accessing a prototype in a loop, it's a good bet that it
-        // should not be treated as a dictionary.
-        if (baseObject->structure()->isDictionary()) {
-            baseObject->flattenDictionaryObject();
-            offset = baseObject->structure()->get(propertyName);
-        }
-
-        ASSERT(!baseObject->structure()->isUncacheableDictionary());
-
-        vPC[0] = getOpcode(op_get_by_id_proto);
-        vPC[5] = baseObject->structure();
-        vPC[6] = offset;
-
-        codeBlock->refStructures(vPC);
-        return;
-    }
-
-    size_t offset = slot.cachedOffset();
-    size_t count = normalizePrototypeChain(callFrame, baseValue, slot.slotBase(), propertyName, offset);
-    if (!count) {
-        vPC[0] = getOpcode(op_get_by_id_generic);
-        return;
-    }
-
-    vPC[0] = getOpcode(op_get_by_id_chain);
-    vPC[4] = structure;
-    vPC[5] = structure->prototypeChain(callFrame);
-    vPC[6] = count;
-    vPC[7] = offset;
-    codeBlock->refStructures(vPC);
-}
-
-NEVER_INLINE void Interpreter::uncacheGetByID(CodeBlock* codeBlock, Instruction* vPC)
-{
-    codeBlock->derefStructures(vPC);
-    vPC[0] = getOpcode(op_get_by_id);
-    vPC[4] = 0;
-}
-
-#endif // USE(INTERPRETER)
-
-JSValue Interpreter::privateExecute(ExecutionFlag flag, RegisterFile* registerFile, CallFrame* callFrame, JSValue* exception)
-{
-    // One-time initialization of our address tables. We have to put this code
-    // here because our labels are only in scope inside this function.
-    if (UNLIKELY(flag == InitializeAndReturn)) {
-        #if HAVE(COMPUTED_GOTO)
-            #define LIST_OPCODE_LABEL(id, length) &&id,
-                static Opcode labels[] = { FOR_EACH_OPCODE_ID(LIST_OPCODE_LABEL) };
-                for (size_t i = 0; i < sizeof(labels) / sizeof(Opcode); ++i)
-                    m_opcodeTable[i] = labels[i];
-            #undef LIST_OPCODE_LABEL
-        #endif // HAVE(COMPUTED_GOTO)
-        return JSValue();
-    }
-
-#if ENABLE(JIT)
-    // Mixing Interpreter + JIT is not supported.
-    ASSERT_NOT_REACHED();
-#endif
-#if !USE(INTERPRETER)
-    UNUSED_PARAM(registerFile);
-    UNUSED_PARAM(callFrame);
-    UNUSED_PARAM(exception);
-    return JSValue();
-#else
-
-    JSGlobalData* globalData = &callFrame->globalData();
-    JSValue exceptionValue;
-    HandlerInfo* handler = 0;
-
-    Instruction* vPC = callFrame->codeBlock()->instructions().begin();
-    Profiler** enabledProfilerReference = Profiler::enabledProfilerReference();
-    unsigned tickCount = globalData->timeoutChecker.ticksUntilNextCheck();
-
-#define CHECK_FOR_EXCEPTION() \
-    do { \
-        if (UNLIKELY(globalData->exception != JSValue())) { \
-            exceptionValue = globalData->exception; \
-            goto vm_throw; \
-        } \
-    } while (0)
-
-#if ENABLE(OPCODE_STATS)
-    OpcodeStats::resetLastInstruction();
-#endif
-
-#define CHECK_FOR_TIMEOUT() \
-    if (!--tickCount) { \
-        if (globalData->timeoutChecker.didTimeOut(callFrame)) { \
-            exceptionValue = jsNull(); \
-            goto vm_throw; \
-        } \
-        tickCount = globalData->timeoutChecker.ticksUntilNextCheck(); \
-    }
-    
-#if ENABLE(OPCODE_SAMPLING)
-    #define SAMPLE(codeBlock, vPC) m_sampler->sample(codeBlock, vPC)
-#else
-    #define SAMPLE(codeBlock, vPC)
-#endif
-
-#if HAVE(COMPUTED_GOTO)
-    #define NEXT_INSTRUCTION() SAMPLE(callFrame->codeBlock(), vPC); goto *vPC->u.opcode
-#if ENABLE(OPCODE_STATS)
-    #define DEFINE_OPCODE(opcode) opcode: OpcodeStats::recordInstruction(opcode);
-#else
-    #define DEFINE_OPCODE(opcode) opcode:
-#endif
-    NEXT_INSTRUCTION();
-#else
-    #define NEXT_INSTRUCTION() SAMPLE(callFrame->codeBlock(), vPC); goto interpreterLoopStart
-#if ENABLE(OPCODE_STATS)
-    #define DEFINE_OPCODE(opcode) case opcode: OpcodeStats::recordInstruction(opcode);
-#else
-    #define DEFINE_OPCODE(opcode) case opcode:
-#endif
-    while (1) { // iterator loop begins
-    interpreterLoopStart:;
-    switch (vPC->u.opcode)
-#endif
-    {
-    DEFINE_OPCODE(op_new_object) {
-        /* new_object dst(r)
-
-           Constructs a new empty Object instance using the original
-           constructor, and puts the result in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        callFrame->r(dst) = JSValue(constructEmptyObject(callFrame));
-
-        vPC += OPCODE_LENGTH(op_new_object);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_new_array) {
-        /* new_array dst(r) firstArg(r) argCount(n)
-
-           Constructs a new Array instance using the original
-           constructor, and puts the result in register dst.
-           The array will contain argCount elements with values
-           taken from registers starting at register firstArg.
-        */
-        int dst = vPC[1].u.operand;
-        int firstArg = vPC[2].u.operand;
-        int argCount = vPC[3].u.operand;
-        ArgList args(callFrame->registers() + firstArg, argCount);
-        callFrame->r(dst) = JSValue(constructArray(callFrame, args));
-
-        vPC += OPCODE_LENGTH(op_new_array);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_new_regexp) {
-        /* new_regexp dst(r) regExp(re)
-
-           Constructs a new RegExp instance using the original
-           constructor from regexp regExp, and puts the result in
-           register dst.
-        */
-        int dst = vPC[1].u.operand;
-        int regExp = vPC[2].u.operand;
-        callFrame->r(dst) = JSValue(new (globalData) RegExpObject(callFrame->scopeChain()->globalObject->regExpStructure(), callFrame->codeBlock()->regexp(regExp)));
-
-        vPC += OPCODE_LENGTH(op_new_regexp);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_mov) {
-        /* mov dst(r) src(r)
-
-           Copies register src to register dst.
-        */
-        int dst = vPC[1].u.operand;
-        int src = vPC[2].u.operand;
-        callFrame->r(dst) = callFrame->r(src);
-
-        vPC += OPCODE_LENGTH(op_mov);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_eq) {
-        /* eq dst(r) src1(r) src2(r)
-
-           Checks whether register src1 and register src2 are equal,
-           as with the ECMAScript '==' operator, and puts the result
-           as a boolean in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue src1 = callFrame->r(vPC[2].u.operand).jsValue();
-        JSValue src2 = callFrame->r(vPC[3].u.operand).jsValue();
-        if (src1.isInt32() && src2.isInt32())
-            callFrame->r(dst) = jsBoolean(src1.asInt32() == src2.asInt32());
-        else {
-            JSValue result = jsBoolean(JSValue::equalSlowCase(callFrame, src1, src2));
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(dst) = result;
-        }
-
-        vPC += OPCODE_LENGTH(op_eq);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_eq_null) {
-        /* eq_null dst(r) src(r)
-
-           Checks whether register src is null, as with the ECMAScript '!='
-           operator, and puts the result as a boolean in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue src = callFrame->r(vPC[2].u.operand).jsValue();
-
-        if (src.isUndefinedOrNull()) {
-            callFrame->r(dst) = jsBoolean(true);
-            vPC += OPCODE_LENGTH(op_eq_null);
-            NEXT_INSTRUCTION();
-        }
-        
-        callFrame->r(dst) = jsBoolean(src.isCell() && src.asCell()->structure()->typeInfo().masqueradesAsUndefined());
-        vPC += OPCODE_LENGTH(op_eq_null);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_neq) {
-        /* neq dst(r) src1(r) src2(r)
-
-           Checks whether register src1 and register src2 are not
-           equal, as with the ECMAScript '!=' operator, and puts the
-           result as a boolean in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue src1 = callFrame->r(vPC[2].u.operand).jsValue();
-        JSValue src2 = callFrame->r(vPC[3].u.operand).jsValue();
-        if (src1.isInt32() && src2.isInt32())
-            callFrame->r(dst) = jsBoolean(src1.asInt32() != src2.asInt32());
-        else {
-            JSValue result = jsBoolean(!JSValue::equalSlowCase(callFrame, src1, src2));
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(dst) = result;
-        }
-
-        vPC += OPCODE_LENGTH(op_neq);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_neq_null) {
-        /* neq_null dst(r) src(r)
-
-           Checks whether register src is not null, as with the ECMAScript '!='
-           operator, and puts the result as a boolean in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue src = callFrame->r(vPC[2].u.operand).jsValue();
-
-        if (src.isUndefinedOrNull()) {
-            callFrame->r(dst) = jsBoolean(false);
-            vPC += OPCODE_LENGTH(op_neq_null);
-            NEXT_INSTRUCTION();
-        }
-        
-        callFrame->r(dst) = jsBoolean(!src.isCell() || !asCell(src)->structure()->typeInfo().masqueradesAsUndefined());
-        vPC += OPCODE_LENGTH(op_neq_null);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_stricteq) {
-        /* stricteq dst(r) src1(r) src2(r)
-
-           Checks whether register src1 and register src2 are strictly
-           equal, as with the ECMAScript '===' operator, and puts the
-           result as a boolean in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue src1 = callFrame->r(vPC[2].u.operand).jsValue();
-        JSValue src2 = callFrame->r(vPC[3].u.operand).jsValue();
-        callFrame->r(dst) = jsBoolean(JSValue::strictEqual(callFrame, src1, src2));
-
-        vPC += OPCODE_LENGTH(op_stricteq);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_nstricteq) {
-        /* nstricteq dst(r) src1(r) src2(r)
-
-           Checks whether register src1 and register src2 are not
-           strictly equal, as with the ECMAScript '!==' operator, and
-           puts the result as a boolean in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue src1 = callFrame->r(vPC[2].u.operand).jsValue();
-        JSValue src2 = callFrame->r(vPC[3].u.operand).jsValue();
-        callFrame->r(dst) = jsBoolean(!JSValue::strictEqual(callFrame, src1, src2));
-
-        vPC += OPCODE_LENGTH(op_nstricteq);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_less) {
-        /* less dst(r) src1(r) src2(r)
-
-           Checks whether register src1 is less than register src2, as
-           with the ECMAScript '<' operator, and puts the result as
-           a boolean in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue src1 = callFrame->r(vPC[2].u.operand).jsValue();
-        JSValue src2 = callFrame->r(vPC[3].u.operand).jsValue();
-        JSValue result = jsBoolean(jsLess(callFrame, src1, src2));
-        CHECK_FOR_EXCEPTION();
-        callFrame->r(dst) = result;
-
-        vPC += OPCODE_LENGTH(op_less);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_lesseq) {
-        /* lesseq dst(r) src1(r) src2(r)
-
-           Checks whether register src1 is less than or equal to
-           register src2, as with the ECMAScript '<=' operator, and
-           puts the result as a boolean in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue src1 = callFrame->r(vPC[2].u.operand).jsValue();
-        JSValue src2 = callFrame->r(vPC[3].u.operand).jsValue();
-        JSValue result = jsBoolean(jsLessEq(callFrame, src1, src2));
-        CHECK_FOR_EXCEPTION();
-        callFrame->r(dst) = result;
-
-        vPC += OPCODE_LENGTH(op_lesseq);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_pre_inc) {
-        /* pre_inc srcDst(r)
-
-           Converts register srcDst to number, adds one, and puts the result
-           back in register srcDst.
-        */
-        int srcDst = vPC[1].u.operand;
-        JSValue v = callFrame->r(srcDst).jsValue();
-        if (v.isInt32() && v.asInt32() < INT_MAX)
-            callFrame->r(srcDst) = jsNumber(callFrame, v.asInt32() + 1);
-        else {
-            JSValue result = jsNumber(callFrame, v.toNumber(callFrame) + 1);
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(srcDst) = result;
-        }
-
-        vPC += OPCODE_LENGTH(op_pre_inc);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_pre_dec) {
-        /* pre_dec srcDst(r)
-
-           Converts register srcDst to number, subtracts one, and puts the result
-           back in register srcDst.
-        */
-        int srcDst = vPC[1].u.operand;
-        JSValue v = callFrame->r(srcDst).jsValue();
-        if (v.isInt32() && v.asInt32() > INT_MIN)
-            callFrame->r(srcDst) = jsNumber(callFrame, v.asInt32() - 1);
-        else {
-            JSValue result = jsNumber(callFrame, v.toNumber(callFrame) - 1);
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(srcDst) = result;
-        }
-
-        vPC += OPCODE_LENGTH(op_pre_dec);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_post_inc) {
-        /* post_inc dst(r) srcDst(r)
-
-           Converts register srcDst to number. The number itself is
-           written to register dst, and the number plus one is written
-           back to register srcDst.
-        */
-        int dst = vPC[1].u.operand;
-        int srcDst = vPC[2].u.operand;
-        JSValue v = callFrame->r(srcDst).jsValue();
-        if (v.isInt32() && v.asInt32() < INT_MAX) {
-            callFrame->r(srcDst) = jsNumber(callFrame, v.asInt32() + 1);
-            callFrame->r(dst) = v;
-        } else {
-            JSValue number = callFrame->r(srcDst).jsValue().toJSNumber(callFrame);
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(srcDst) = jsNumber(callFrame, number.uncheckedGetNumber() + 1);
-            callFrame->r(dst) = number;
-        }
-
-        vPC += OPCODE_LENGTH(op_post_inc);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_post_dec) {
-        /* post_dec dst(r) srcDst(r)
-
-           Converts register srcDst to number. The number itself is
-           written to register dst, and the number minus one is written
-           back to register srcDst.
-        */
-        int dst = vPC[1].u.operand;
-        int srcDst = vPC[2].u.operand;
-        JSValue v = callFrame->r(srcDst).jsValue();
-        if (v.isInt32() && v.asInt32() > INT_MIN) {
-            callFrame->r(srcDst) = jsNumber(callFrame, v.asInt32() - 1);
-            callFrame->r(dst) = v;
-        } else {
-            JSValue number = callFrame->r(srcDst).jsValue().toJSNumber(callFrame);
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(srcDst) = jsNumber(callFrame, number.uncheckedGetNumber() - 1);
-            callFrame->r(dst) = number;
-        }
-
-        vPC += OPCODE_LENGTH(op_post_dec);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_to_jsnumber) {
-        /* to_jsnumber dst(r) src(r)
-
-           Converts register src to number, and puts the result
-           in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        int src = vPC[2].u.operand;
-
-        JSValue srcVal = callFrame->r(src).jsValue();
-
-        if (LIKELY(srcVal.isNumber()))
-            callFrame->r(dst) = callFrame->r(src);
-        else {
-            JSValue result = srcVal.toJSNumber(callFrame);
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(dst) = result;
-        }
-
-        vPC += OPCODE_LENGTH(op_to_jsnumber);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_negate) {
-        /* negate dst(r) src(r)
-
-           Converts register src to number, negates it, and puts the
-           result in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue src = callFrame->r(vPC[2].u.operand).jsValue();
-        if (src.isInt32() && src.asInt32())
-            callFrame->r(dst) = jsNumber(callFrame, -src.asInt32());
-        else {
-            JSValue result = jsNumber(callFrame, -src.toNumber(callFrame));
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(dst) = result;
-        }
-
-        vPC += OPCODE_LENGTH(op_negate);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_add) {
-        /* add dst(r) src1(r) src2(r)
-
-           Adds register src1 and register src2, and puts the result
-           in register dst. (JS add may be string concatenation or
-           numeric add, depending on the types of the operands.)
-        */
-        int dst = vPC[1].u.operand;
-        JSValue src1 = callFrame->r(vPC[2].u.operand).jsValue();
-        JSValue src2 = callFrame->r(vPC[3].u.operand).jsValue();
-        if (src1.isInt32() && src2.isInt32() && !(src1.asInt32() | (src2.asInt32() & 0xc0000000))) // no overflow
-            callFrame->r(dst) = jsNumber(callFrame, src1.asInt32() + src2.asInt32());
-        else {
-            JSValue result = jsAdd(callFrame, src1, src2);
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(dst) = result;
-        }
-        vPC += OPCODE_LENGTH(op_add);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_mul) {
-        /* mul dst(r) src1(r) src2(r)
-
-           Multiplies register src1 and register src2 (converted to
-           numbers), and puts the product in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue src1 = callFrame->r(vPC[2].u.operand).jsValue();
-        JSValue src2 = callFrame->r(vPC[3].u.operand).jsValue();
-        if (src1.isInt32() && src2.isInt32() && !(src1.asInt32() | src2.asInt32() >> 15)) // no overflow
-                callFrame->r(dst) = jsNumber(callFrame, src1.asInt32() * src2.asInt32());
-        else {
-            JSValue result = jsNumber(callFrame, src1.toNumber(callFrame) * src2.toNumber(callFrame));
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(dst) = result;
-        }
-
-        vPC += OPCODE_LENGTH(op_mul);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_div) {
-        /* div dst(r) dividend(r) divisor(r)
-
-           Divides register dividend (converted to number) by the
-           register divisor (converted to number), and puts the
-           quotient in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue dividend = callFrame->r(vPC[2].u.operand).jsValue();
-        JSValue divisor = callFrame->r(vPC[3].u.operand).jsValue();
-
-        JSValue result = jsNumber(callFrame, dividend.toNumber(callFrame) / divisor.toNumber(callFrame));
-        CHECK_FOR_EXCEPTION();
-        callFrame->r(dst) = result;
-
-        vPC += OPCODE_LENGTH(op_div);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_mod) {
-        /* mod dst(r) dividend(r) divisor(r)
-
-           Divides register dividend (converted to number) by
-           register divisor (converted to number), and puts the
-           remainder in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue dividend = callFrame->r(vPC[2].u.operand).jsValue();
-        JSValue divisor = callFrame->r(vPC[3].u.operand).jsValue();
-
-        if (dividend.isInt32() && divisor.isInt32() && divisor.asInt32() != 0) {
-            JSValue result = jsNumber(callFrame, dividend.asInt32() % divisor.asInt32());
-            ASSERT(result);
-            callFrame->r(dst) = result;
-            vPC += OPCODE_LENGTH(op_mod);
-            NEXT_INSTRUCTION();
-        }
-
-        // Conversion to double must happen outside the call to fmod since the
-        // order of argument evaluation is not guaranteed.
-        double d1 = dividend.toNumber(callFrame);
-        double d2 = divisor.toNumber(callFrame);
-        JSValue result = jsNumber(callFrame, fmod(d1, d2));
-        CHECK_FOR_EXCEPTION();
-        callFrame->r(dst) = result;
-        vPC += OPCODE_LENGTH(op_mod);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_sub) {
-        /* sub dst(r) src1(r) src2(r)
-
-           Subtracts register src2 (converted to number) from register
-           src1 (converted to number), and puts the difference in
-           register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue src1 = callFrame->r(vPC[2].u.operand).jsValue();
-        JSValue src2 = callFrame->r(vPC[3].u.operand).jsValue();
-        if (src1.isInt32() && src2.isInt32() && !(src1.asInt32() | (src2.asInt32() & 0xc0000000))) // no overflow
-            callFrame->r(dst) = jsNumber(callFrame, src1.asInt32() - src2.asInt32());
-        else {
-            JSValue result = jsNumber(callFrame, src1.toNumber(callFrame) - src2.toNumber(callFrame));
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(dst) = result;
-        }
-        vPC += OPCODE_LENGTH(op_sub);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_lshift) {
-        /* lshift dst(r) val(r) shift(r)
-
-           Performs left shift of register val (converted to int32) by
-           register shift (converted to uint32), and puts the result
-           in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue val = callFrame->r(vPC[2].u.operand).jsValue();
-        JSValue shift = callFrame->r(vPC[3].u.operand).jsValue();
-
-        if (val.isInt32() && shift.isInt32())
-            callFrame->r(dst) = jsNumber(callFrame, val.asInt32() << (shift.asInt32() & 0x1f));
-        else {
-            JSValue result = jsNumber(callFrame, (val.toInt32(callFrame)) << (shift.toUInt32(callFrame) & 0x1f));
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(dst) = result;
-        }
-
-        vPC += OPCODE_LENGTH(op_lshift);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_rshift) {
-        /* rshift dst(r) val(r) shift(r)
-
-           Performs arithmetic right shift of register val (converted
-           to int32) by register shift (converted to
-           uint32), and puts the result in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue val = callFrame->r(vPC[2].u.operand).jsValue();
-        JSValue shift = callFrame->r(vPC[3].u.operand).jsValue();
-
-        if (val.isInt32() && shift.isInt32())
-            callFrame->r(dst) = jsNumber(callFrame, val.asInt32() >> (shift.asInt32() & 0x1f));
-        else {
-            JSValue result = jsNumber(callFrame, (val.toInt32(callFrame)) >> (shift.toUInt32(callFrame) & 0x1f));
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(dst) = result;
-        }
-
-        vPC += OPCODE_LENGTH(op_rshift);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_urshift) {
-        /* rshift dst(r) val(r) shift(r)
-
-           Performs logical right shift of register val (converted
-           to uint32) by register shift (converted to
-           uint32), and puts the result in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue val = callFrame->r(vPC[2].u.operand).jsValue();
-        JSValue shift = callFrame->r(vPC[3].u.operand).jsValue();
-        if (val.isUInt32() && shift.isInt32())
-            callFrame->r(dst) = jsNumber(callFrame, val.asInt32() >> (shift.asInt32() & 0x1f));
-        else {
-            JSValue result = jsNumber(callFrame, (val.toUInt32(callFrame)) >> (shift.toUInt32(callFrame) & 0x1f));
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(dst) = result;
-        }
-
-        vPC += OPCODE_LENGTH(op_urshift);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_bitand) {
-        /* bitand dst(r) src1(r) src2(r)
-
-           Computes bitwise AND of register src1 (converted to int32)
-           and register src2 (converted to int32), and puts the result
-           in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue src1 = callFrame->r(vPC[2].u.operand).jsValue();
-        JSValue src2 = callFrame->r(vPC[3].u.operand).jsValue();
-        if (src1.isInt32() && src2.isInt32())
-            callFrame->r(dst) = jsNumber(callFrame, src1.asInt32() & src2.asInt32());
-        else {
-            JSValue result = jsNumber(callFrame, src1.toInt32(callFrame) & src2.toInt32(callFrame));
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(dst) = result;
-        }
-
-        vPC += OPCODE_LENGTH(op_bitand);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_bitxor) {
-        /* bitxor dst(r) src1(r) src2(r)
-
-           Computes bitwise XOR of register src1 (converted to int32)
-           and register src2 (converted to int32), and puts the result
-           in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue src1 = callFrame->r(vPC[2].u.operand).jsValue();
-        JSValue src2 = callFrame->r(vPC[3].u.operand).jsValue();
-        if (src1.isInt32() && src2.isInt32())
-            callFrame->r(dst) = jsNumber(callFrame, src1.asInt32() ^ src2.asInt32());
-        else {
-            JSValue result = jsNumber(callFrame, src1.toInt32(callFrame) ^ src2.toInt32(callFrame));
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(dst) = result;
-        }
-
-        vPC += OPCODE_LENGTH(op_bitxor);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_bitor) {
-        /* bitor dst(r) src1(r) src2(r)
-
-           Computes bitwise OR of register src1 (converted to int32)
-           and register src2 (converted to int32), and puts the
-           result in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue src1 = callFrame->r(vPC[2].u.operand).jsValue();
-        JSValue src2 = callFrame->r(vPC[3].u.operand).jsValue();
-        if (src1.isInt32() && src2.isInt32())
-            callFrame->r(dst) = jsNumber(callFrame, src1.asInt32() | src2.asInt32());
-        else {
-            JSValue result = jsNumber(callFrame, src1.toInt32(callFrame) | src2.toInt32(callFrame));
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(dst) = result;
-        }
-
-        vPC += OPCODE_LENGTH(op_bitor);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_bitnot) {
-        /* bitnot dst(r) src(r)
-
-           Computes bitwise NOT of register src1 (converted to int32),
-           and puts the result in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        JSValue src = callFrame->r(vPC[2].u.operand).jsValue();
-        if (src.isInt32())
-            callFrame->r(dst) = jsNumber(callFrame, ~src.asInt32());
-        else {
-            JSValue result = jsNumber(callFrame, ~src.toInt32(callFrame));
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(dst) = result;
-        }
-        vPC += OPCODE_LENGTH(op_bitnot);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_not) {
-        /* not dst(r) src(r)
-
-           Computes logical NOT of register src (converted to
-           boolean), and puts the result in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        int src = vPC[2].u.operand;
-        JSValue result = jsBoolean(!callFrame->r(src).jsValue().toBoolean(callFrame));
-        CHECK_FOR_EXCEPTION();
-        callFrame->r(dst) = result;
-
-        vPC += OPCODE_LENGTH(op_not);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_instanceof) {
-        /* instanceof dst(r) value(r) constructor(r) constructorProto(r)
-
-           Tests whether register value is an instance of register
-           constructor, and puts the boolean result in register
-           dst. Register constructorProto must contain the "prototype"
-           property (not the actual prototype) of the object in
-           register constructor. This lookup is separated so that
-           polymorphic inline caching can apply.
-
-           Raises an exception if register constructor is not an
-           object.
-        */
-        int dst = vPC[1].u.operand;
-        int value = vPC[2].u.operand;
-        int base = vPC[3].u.operand;
-        int baseProto = vPC[4].u.operand;
-
-        JSValue baseVal = callFrame->r(base).jsValue();
-
-        if (isInvalidParamForInstanceOf(callFrame, callFrame->codeBlock(), vPC, baseVal, exceptionValue))
-            goto vm_throw;
-
-        bool result = asObject(baseVal)->hasInstance(callFrame, callFrame->r(value).jsValue(), callFrame->r(baseProto).jsValue());
-        CHECK_FOR_EXCEPTION();
-        callFrame->r(dst) = jsBoolean(result);
-
-        vPC += OPCODE_LENGTH(op_instanceof);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_typeof) {
-        /* typeof dst(r) src(r)
-
-           Determines the type string for src according to ECMAScript
-           rules, and puts the result in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        int src = vPC[2].u.operand;
-        callFrame->r(dst) = JSValue(jsTypeStringForValue(callFrame, callFrame->r(src).jsValue()));
-
-        vPC += OPCODE_LENGTH(op_typeof);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_is_undefined) {
-        /* is_undefined dst(r) src(r)
-
-           Determines whether the type string for src according to
-           the ECMAScript rules is "undefined", and puts the result
-           in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        int src = vPC[2].u.operand;
-        JSValue v = callFrame->r(src).jsValue();
-        callFrame->r(dst) = jsBoolean(v.isCell() ? v.asCell()->structure()->typeInfo().masqueradesAsUndefined() : v.isUndefined());
-
-        vPC += OPCODE_LENGTH(op_is_undefined);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_is_boolean) {
-        /* is_boolean dst(r) src(r)
-
-           Determines whether the type string for src according to
-           the ECMAScript rules is "boolean", and puts the result
-           in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        int src = vPC[2].u.operand;
-        callFrame->r(dst) = jsBoolean(callFrame->r(src).jsValue().isBoolean());
-
-        vPC += OPCODE_LENGTH(op_is_boolean);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_is_number) {
-        /* is_number dst(r) src(r)
-
-           Determines whether the type string for src according to
-           the ECMAScript rules is "number", and puts the result
-           in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        int src = vPC[2].u.operand;
-        callFrame->r(dst) = jsBoolean(callFrame->r(src).jsValue().isNumber());
-
-        vPC += OPCODE_LENGTH(op_is_number);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_is_string) {
-        /* is_string dst(r) src(r)
-
-           Determines whether the type string for src according to
-           the ECMAScript rules is "string", and puts the result
-           in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        int src = vPC[2].u.operand;
-        callFrame->r(dst) = jsBoolean(callFrame->r(src).jsValue().isString());
-
-        vPC += OPCODE_LENGTH(op_is_string);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_is_object) {
-        /* is_object dst(r) src(r)
-
-           Determines whether the type string for src according to
-           the ECMAScript rules is "object", and puts the result
-           in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        int src = vPC[2].u.operand;
-        callFrame->r(dst) = jsBoolean(jsIsObjectType(callFrame->r(src).jsValue()));
-
-        vPC += OPCODE_LENGTH(op_is_object);
-        NEXT_INSTRUCTION();
+            debugger->didReachBreakpoint(callFrame);
+            break;
     }
-    DEFINE_OPCODE(op_is_function) {
-        /* is_function dst(r) src(r)
-
-           Determines whether the type string for src according to
-           the ECMAScript rules is "function", and puts the result
-           in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        int src = vPC[2].u.operand;
-        callFrame->r(dst) = jsBoolean(jsIsFunctionType(callFrame->r(src).jsValue()));
-
-        vPC += OPCODE_LENGTH(op_is_function);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_in) {
-        /* in dst(r) property(r) base(r)
-
-           Tests whether register base has a property named register
-           property, and puts the boolean result in register dst.
-
-           Raises an exception if register constructor is not an
-           object.
-        */
-        int dst = vPC[1].u.operand;
-        int property = vPC[2].u.operand;
-        int base = vPC[3].u.operand;
-
-        JSValue baseVal = callFrame->r(base).jsValue();
-        if (isInvalidParamForIn(callFrame, callFrame->codeBlock(), vPC, baseVal, exceptionValue))
-            goto vm_throw;
-
-        JSObject* baseObj = asObject(baseVal);
-
-        JSValue propName = callFrame->r(property).jsValue();
-
-        uint32_t i;
-        if (propName.getUInt32(i))
-            callFrame->r(dst) = jsBoolean(baseObj->hasProperty(callFrame, i));
-        else {
-            Identifier property(callFrame, propName.toString(callFrame));
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(dst) = jsBoolean(baseObj->hasProperty(callFrame, property));
-        }
-
-        vPC += OPCODE_LENGTH(op_in);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_resolve) {
-        /* resolve dst(r) property(id)
-
-           Looks up the property named by identifier property in the
-           scope chain, and writes the resulting value to register
-           dst. If the property is not found, raises an exception.
-        */
-        if (UNLIKELY(!resolve(callFrame, vPC, exceptionValue)))
-            goto vm_throw;
-
-        vPC += OPCODE_LENGTH(op_resolve);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_resolve_skip) {
-        /* resolve_skip dst(r) property(id) skip(n)
-
-         Looks up the property named by identifier property in the
-         scope chain skipping the top 'skip' levels, and writes the resulting
-         value to register dst. If the property is not found, raises an exception.
-         */
-        if (UNLIKELY(!resolveSkip(callFrame, vPC, exceptionValue)))
-            goto vm_throw;
-
-        vPC += OPCODE_LENGTH(op_resolve_skip);
-
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_resolve_global) {
-        /* resolve_skip dst(r) globalObject(c) property(id) structure(sID) offset(n)
-         
-           Performs a dynamic property lookup for the given property, on the provided
-           global object.  If structure matches the Structure of the global then perform
-           a fast lookup using the case offset, otherwise fall back to a full resolve and
-           cache the new structure and offset
-         */
-        if (UNLIKELY(!resolveGlobal(callFrame, vPC, exceptionValue)))
-            goto vm_throw;
-        
-        vPC += OPCODE_LENGTH(op_resolve_global);
-        
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_get_global_var) {
-        /* get_global_var dst(r) globalObject(c) index(n)
-
-           Gets the global var at global slot index and places it in register dst.
-         */
-        int dst = vPC[1].u.operand;
-        JSGlobalObject* scope = static_cast<JSGlobalObject*>(vPC[2].u.jsCell);
-        ASSERT(scope->isGlobalObject());
-        int index = vPC[3].u.operand;
-
-        callFrame->r(dst) = scope->registerAt(index);
-        vPC += OPCODE_LENGTH(op_get_global_var);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_put_global_var) {
-        /* put_global_var globalObject(c) index(n) value(r)
-         
-           Puts value into global slot index.
-         */
-        JSGlobalObject* scope = static_cast<JSGlobalObject*>(vPC[1].u.jsCell);
-        ASSERT(scope->isGlobalObject());
-        int index = vPC[2].u.operand;
-        int value = vPC[3].u.operand;
-        
-        scope->registerAt(index) = JSValue(callFrame->r(value).jsValue());
-        vPC += OPCODE_LENGTH(op_put_global_var);
-        NEXT_INSTRUCTION();
-    }            
-    DEFINE_OPCODE(op_get_scoped_var) {
-        /* get_scoped_var dst(r) index(n) skip(n)
-
-         Loads the contents of the index-th local from the scope skip nodes from
-         the top of the scope chain, and places it in register dst
-         */
-        int dst = vPC[1].u.operand;
-        int index = vPC[2].u.operand;
-        int skip = vPC[3].u.operand + callFrame->codeBlock()->needsFullScopeChain();
-
-        ScopeChainNode* scopeChain = callFrame->scopeChain();
-        ScopeChainIterator iter = scopeChain->begin();
-        ScopeChainIterator end = scopeChain->end();
-        ASSERT(iter != end);
-        while (skip--) {
-            ++iter;
-            ASSERT(iter != end);
-        }
-
-        ASSERT((*iter)->isVariableObject());
-        JSVariableObject* scope = static_cast<JSVariableObject*>(*iter);
-        callFrame->r(dst) = scope->registerAt(index);
-        vPC += OPCODE_LENGTH(op_get_scoped_var);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_put_scoped_var) {
-        /* put_scoped_var index(n) skip(n) value(r)
-
-         */
-        int index = vPC[1].u.operand;
-        int skip = vPC[2].u.operand + callFrame->codeBlock()->needsFullScopeChain();
-        int value = vPC[3].u.operand;
-
-        ScopeChainNode* scopeChain = callFrame->scopeChain();
-        ScopeChainIterator iter = scopeChain->begin();
-        ScopeChainIterator end = scopeChain->end();
-        ASSERT(iter != end);
-        while (skip--) {
-            ++iter;
-            ASSERT(iter != end);
-        }
-
-        ASSERT((*iter)->isVariableObject());
-        JSVariableObject* scope = static_cast<JSVariableObject*>(*iter);
-        scope->registerAt(index) = JSValue(callFrame->r(value).jsValue());
-        vPC += OPCODE_LENGTH(op_put_scoped_var);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_resolve_base) {
-        /* resolve_base dst(r) property(id)
-
-           Searches the scope chain for an object containing
-           identifier property, and if one is found, writes it to
-           register dst. If none is found, the outermost scope (which
-           will be the global object) is stored in register dst.
-        */
-        resolveBase(callFrame, vPC);
-
-        vPC += OPCODE_LENGTH(op_resolve_base);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_resolve_with_base) {
-        /* resolve_with_base baseDst(r) propDst(r) property(id)
-
-           Searches the scope chain for an object containing
-           identifier property, and if one is found, writes it to
-           register srcDst, and the retrieved property value to register
-           propDst. If the property is not found, raises an exception.
-
-           This is more efficient than doing resolve_base followed by
-           resolve, or resolve_base followed by get_by_id, as it
-           avoids duplicate hash lookups.
-        */
-        if (UNLIKELY(!resolveBaseAndProperty(callFrame, vPC, exceptionValue)))
-            goto vm_throw;
-
-        vPC += OPCODE_LENGTH(op_resolve_with_base);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_get_by_id) {
-        /* get_by_id dst(r) base(r) property(id) structure(sID) nop(n) nop(n) nop(n)
-
-           Generic property access: Gets the property named by identifier
-           property from the value base, and puts the result in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        int base = vPC[2].u.operand;
-        int property = vPC[3].u.operand;
-
-        CodeBlock* codeBlock = callFrame->codeBlock();
-        Identifier& ident = codeBlock->identifier(property);
-        JSValue baseValue = callFrame->r(base).jsValue();
-        PropertySlot slot(baseValue);
-        JSValue result = baseValue.get(callFrame, ident, slot);
-        CHECK_FOR_EXCEPTION();
-
-        tryCacheGetByID(callFrame, codeBlock, vPC, baseValue, ident, slot);
-
-        callFrame->r(dst) = result;
-        vPC += OPCODE_LENGTH(op_get_by_id);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_get_by_id_self) {
-        /* op_get_by_id_self dst(r) base(r) property(id) structure(sID) offset(n) nop(n) nop(n)
-
-           Cached property access: Attempts to get a cached property from the
-           value base. If the cache misses, op_get_by_id_self reverts to
-           op_get_by_id.
-        */
-        int base = vPC[2].u.operand;
-        JSValue baseValue = callFrame->r(base).jsValue();
-
-        if (LIKELY(baseValue.isCell())) {
-            JSCell* baseCell = asCell(baseValue);
-            Structure* structure = vPC[4].u.structure;
-
-            if (LIKELY(baseCell->structure() == structure)) {
-                ASSERT(baseCell->isObject());
-                JSObject* baseObject = asObject(baseCell);
-                int dst = vPC[1].u.operand;
-                int offset = vPC[5].u.operand;
-
-                ASSERT(baseObject->get(callFrame, callFrame->codeBlock()->identifier(vPC[3].u.operand)) == baseObject->getDirectOffset(offset));
-                callFrame->r(dst) = JSValue(baseObject->getDirectOffset(offset));
-
-                vPC += OPCODE_LENGTH(op_get_by_id_self);
-                NEXT_INSTRUCTION();
-            }
-        }
-
-        uncacheGetByID(callFrame->codeBlock(), vPC);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_get_by_id_proto) {
-        /* op_get_by_id_proto dst(r) base(r) property(id) structure(sID) prototypeStructure(sID) offset(n) nop(n)
-
-           Cached property access: Attempts to get a cached property from the
-           value base's prototype. If the cache misses, op_get_by_id_proto
-           reverts to op_get_by_id.
-        */
-        int base = vPC[2].u.operand;
-        JSValue baseValue = callFrame->r(base).jsValue();
-
-        if (LIKELY(baseValue.isCell())) {
-            JSCell* baseCell = asCell(baseValue);
-            Structure* structure = vPC[4].u.structure;
-
-            if (LIKELY(baseCell->structure() == structure)) {
-                ASSERT(structure->prototypeForLookup(callFrame).isObject());
-                JSObject* protoObject = asObject(structure->prototypeForLookup(callFrame));
-                Structure* prototypeStructure = vPC[5].u.structure;
-
-                if (LIKELY(protoObject->structure() == prototypeStructure)) {
-                    int dst = vPC[1].u.operand;
-                    int offset = vPC[6].u.operand;
-
-                    ASSERT(protoObject->get(callFrame, callFrame->codeBlock()->identifier(vPC[3].u.operand)) == protoObject->getDirectOffset(offset));
-                    ASSERT(baseValue.get(callFrame, callFrame->codeBlock()->identifier(vPC[3].u.operand)) == protoObject->getDirectOffset(offset));
-                    callFrame->r(dst) = JSValue(protoObject->getDirectOffset(offset));
-
-                    vPC += OPCODE_LENGTH(op_get_by_id_proto);
-                    NEXT_INSTRUCTION();
-                }
-            }
-        }
-
-        uncacheGetByID(callFrame->codeBlock(), vPC);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_get_by_id_self_list) {
-        // Polymorphic self access caching currently only supported when JITting.
-        ASSERT_NOT_REACHED();
-        // This case of the switch must not be empty, else (op_get_by_id_self_list == op_get_by_id_chain)!
-        vPC += OPCODE_LENGTH(op_get_by_id_self_list);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_get_by_id_proto_list) {
-        // Polymorphic prototype access caching currently only supported when JITting.
-        ASSERT_NOT_REACHED();
-        // This case of the switch must not be empty, else (op_get_by_id_proto_list == op_get_by_id_chain)!
-        vPC += OPCODE_LENGTH(op_get_by_id_proto_list);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_get_by_id_chain) {
-        /* op_get_by_id_chain dst(r) base(r) property(id) structure(sID) structureChain(chain) count(n) offset(n)
-
-           Cached property access: Attempts to get a cached property from the
-           value base's prototype chain. If the cache misses, op_get_by_id_chain
-           reverts to op_get_by_id.
-        */
-        int base = vPC[2].u.operand;
-        JSValue baseValue = callFrame->r(base).jsValue();
-
-        if (LIKELY(baseValue.isCell())) {
-            JSCell* baseCell = asCell(baseValue);
-            Structure* structure = vPC[4].u.structure;
-
-            if (LIKELY(baseCell->structure() == structure)) {
-                RefPtr<Structure>* it = vPC[5].u.structureChain->head();
-                size_t count = vPC[6].u.operand;
-                RefPtr<Structure>* end = it + count;
-
-                while (true) {
-                    JSObject* baseObject = asObject(baseCell->structure()->prototypeForLookup(callFrame));
-
-                    if (UNLIKELY(baseObject->structure() != (*it).get()))
-                        break;
-
-                    if (++it == end) {
-                        int dst = vPC[1].u.operand;
-                        int offset = vPC[7].u.operand;
-
-                        ASSERT(baseObject->get(callFrame, callFrame->codeBlock()->identifier(vPC[3].u.operand)) == baseObject->getDirectOffset(offset));
-                        ASSERT(baseValue.get(callFrame, callFrame->codeBlock()->identifier(vPC[3].u.operand)) == baseObject->getDirectOffset(offset));
-                        callFrame->r(dst) = JSValue(baseObject->getDirectOffset(offset));
-
-                        vPC += OPCODE_LENGTH(op_get_by_id_chain);
-                        NEXT_INSTRUCTION();
-                    }
-
-                    // Update baseCell, so that next time around the loop we'll pick up the prototype's prototype.
-                    baseCell = baseObject;
-                }
-            }
-        }
-
-        uncacheGetByID(callFrame->codeBlock(), vPC);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_get_by_id_generic) {
-        /* op_get_by_id_generic dst(r) base(r) property(id) nop(sID) nop(n) nop(n) nop(n)
-
-           Generic property access: Gets the property named by identifier
-           property from the value base, and puts the result in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        int base = vPC[2].u.operand;
-        int property = vPC[3].u.operand;
-
-        Identifier& ident = callFrame->codeBlock()->identifier(property);
-        JSValue baseValue = callFrame->r(base).jsValue();
-        PropertySlot slot(baseValue);
-        JSValue result = baseValue.get(callFrame, ident, slot);
-        CHECK_FOR_EXCEPTION();
-
-        callFrame->r(dst) = result;
-        vPC += OPCODE_LENGTH(op_get_by_id_generic);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_get_array_length) {
-        /* op_get_array_length dst(r) base(r) property(id) nop(sID) nop(n) nop(n) nop(n)
-
-           Cached property access: Gets the length of the array in register base,
-           and puts the result in register dst. If register base does not hold
-           an array, op_get_array_length reverts to op_get_by_id.
-        */
-
-        int base = vPC[2].u.operand;
-        JSValue baseValue = callFrame->r(base).jsValue();
-        if (LIKELY(isJSArray(globalData, baseValue))) {
-            int dst = vPC[1].u.operand;
-            callFrame->r(dst) = jsNumber(callFrame, asArray(baseValue)->length());
-            vPC += OPCODE_LENGTH(op_get_array_length);
-            NEXT_INSTRUCTION();
-        }
-
-        uncacheGetByID(callFrame->codeBlock(), vPC);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_get_string_length) {
-        /* op_get_string_length dst(r) base(r) property(id) nop(sID) nop(n) nop(n) nop(n)
-
-           Cached property access: Gets the length of the string in register base,
-           and puts the result in register dst. If register base does not hold
-           a string, op_get_string_length reverts to op_get_by_id.
-        */
-
-        int base = vPC[2].u.operand;
-        JSValue baseValue = callFrame->r(base).jsValue();
-        if (LIKELY(isJSString(globalData, baseValue))) {
-            int dst = vPC[1].u.operand;
-            callFrame->r(dst) = jsNumber(callFrame, asString(baseValue)->length());
-            vPC += OPCODE_LENGTH(op_get_string_length);
-            NEXT_INSTRUCTION();
-        }
-
-        uncacheGetByID(callFrame->codeBlock(), vPC);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_put_by_id) {
-        /* put_by_id base(r) property(id) value(r) nop(n) nop(n) nop(n) nop(n)
-
-           Generic property access: Sets the property named by identifier
-           property, belonging to register base, to register value.
-
-           Unlike many opcodes, this one does not write any output to
-           the register file.
-        */
-
-        int base = vPC[1].u.operand;
-        int property = vPC[2].u.operand;
-        int value = vPC[3].u.operand;
-
-        CodeBlock* codeBlock = callFrame->codeBlock();
-        JSValue baseValue = callFrame->r(base).jsValue();
-        Identifier& ident = codeBlock->identifier(property);
-        PutPropertySlot slot;
-        baseValue.put(callFrame, ident, callFrame->r(value).jsValue(), slot);
-        CHECK_FOR_EXCEPTION();
-
-        tryCachePutByID(callFrame, codeBlock, vPC, baseValue, slot);
-
-        vPC += OPCODE_LENGTH(op_put_by_id);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_put_by_id_transition) {
-        /* op_put_by_id_transition base(r) property(id) value(r) oldStructure(sID) newStructure(sID) structureChain(chain) offset(n)
-         
-           Cached property access: Attempts to set a new property with a cached transition
-           property named by identifier property, belonging to register base,
-           to register value. If the cache misses, op_put_by_id_transition
-           reverts to op_put_by_id_generic.
-         
-           Unlike many opcodes, this one does not write any output to
-           the register file.
-         */
-        int base = vPC[1].u.operand;
-        JSValue baseValue = callFrame->r(base).jsValue();
-        
-        if (LIKELY(baseValue.isCell())) {
-            JSCell* baseCell = asCell(baseValue);
-            Structure* oldStructure = vPC[4].u.structure;
-            Structure* newStructure = vPC[5].u.structure;
-            
-            if (LIKELY(baseCell->structure() == oldStructure)) {
-                ASSERT(baseCell->isObject());
-                JSObject* baseObject = asObject(baseCell);
-
-                RefPtr<Structure>* it = vPC[6].u.structureChain->head();
-
-                JSValue proto = baseObject->structure()->prototypeForLookup(callFrame);
-                while (!proto.isNull()) {
-                    if (UNLIKELY(asObject(proto)->structure() != (*it).get())) {
-                        uncachePutByID(callFrame->codeBlock(), vPC);
-                        NEXT_INSTRUCTION();
-                    }
-                    ++it;
-                    proto = asObject(proto)->structure()->prototypeForLookup(callFrame);
-                }
-
-                baseObject->transitionTo(newStructure);
-
-                int value = vPC[3].u.operand;
-                unsigned offset = vPC[7].u.operand;
-                ASSERT(baseObject->offsetForLocation(baseObject->getDirectLocation(callFrame->codeBlock()->identifier(vPC[2].u.operand))) == offset);
-                baseObject->putDirectOffset(offset, callFrame->r(value).jsValue());
-
-                vPC += OPCODE_LENGTH(op_put_by_id_transition);
-                NEXT_INSTRUCTION();
-            }
-        }
-        
-        uncachePutByID(callFrame->codeBlock(), vPC);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_put_by_id_replace) {
-        /* op_put_by_id_replace base(r) property(id) value(r) structure(sID) offset(n) nop(n) nop(n)
-
-           Cached property access: Attempts to set a pre-existing, cached
-           property named by identifier property, belonging to register base,
-           to register value. If the cache misses, op_put_by_id_replace
-           reverts to op_put_by_id.
-
-           Unlike many opcodes, this one does not write any output to
-           the register file.
-        */
-        int base = vPC[1].u.operand;
-        JSValue baseValue = callFrame->r(base).jsValue();
-
-        if (LIKELY(baseValue.isCell())) {
-            JSCell* baseCell = asCell(baseValue);
-            Structure* structure = vPC[4].u.structure;
-
-            if (LIKELY(baseCell->structure() == structure)) {
-                ASSERT(baseCell->isObject());
-                JSObject* baseObject = asObject(baseCell);
-                int value = vPC[3].u.operand;
-                unsigned offset = vPC[5].u.operand;
-                
-                ASSERT(baseObject->offsetForLocation(baseObject->getDirectLocation(callFrame->codeBlock()->identifier(vPC[2].u.operand))) == offset);
-                baseObject->putDirectOffset(offset, callFrame->r(value).jsValue());
-
-                vPC += OPCODE_LENGTH(op_put_by_id_replace);
-                NEXT_INSTRUCTION();
-            }
-        }
-
-        uncachePutByID(callFrame->codeBlock(), vPC);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_put_by_id_generic) {
-        /* op_put_by_id_generic base(r) property(id) value(r) nop(n) nop(n) nop(n) nop(n)
-
-           Generic property access: Sets the property named by identifier
-           property, belonging to register base, to register value.
-
-           Unlike many opcodes, this one does not write any output to
-           the register file.
-        */
-        int base = vPC[1].u.operand;
-        int property = vPC[2].u.operand;
-        int value = vPC[3].u.operand;
-
-        JSValue baseValue = callFrame->r(base).jsValue();
-        Identifier& ident = callFrame->codeBlock()->identifier(property);
-        PutPropertySlot slot;
-        baseValue.put(callFrame, ident, callFrame->r(value).jsValue(), slot);
-        CHECK_FOR_EXCEPTION();
-
-        vPC += OPCODE_LENGTH(op_put_by_id_generic);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_del_by_id) {
-        /* del_by_id dst(r) base(r) property(id)
-
-           Converts register base to Object, deletes the property
-           named by identifier property from the object, and writes a
-           boolean indicating success (if true) or failure (if false)
-           to register dst.
-        */
-        int dst = vPC[1].u.operand;
-        int base = vPC[2].u.operand;
-        int property = vPC[3].u.operand;
-
-        JSObject* baseObj = callFrame->r(base).jsValue().toObject(callFrame);
-        Identifier& ident = callFrame->codeBlock()->identifier(property);
-        JSValue result = jsBoolean(baseObj->deleteProperty(callFrame, ident));
-        CHECK_FOR_EXCEPTION();
-        callFrame->r(dst) = result;
-        vPC += OPCODE_LENGTH(op_del_by_id);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_get_by_pname) {
-        int dst = vPC[1].u.operand;
-        int base = vPC[2].u.operand;
-        int property = vPC[3].u.operand;
-        int expected = vPC[4].u.operand;
-        int iter = vPC[5].u.operand;
-        int i = vPC[6].u.operand;
-
-        JSValue baseValue = callFrame->r(base).jsValue();
-        JSPropertyNameIterator* it = callFrame->r(iter).propertyNameIterator();
-        JSValue subscript = callFrame->r(property).jsValue();
-        JSValue expectedSubscript = callFrame->r(expected).jsValue();
-        int index = callFrame->r(i).i() - 1;
-        JSValue result;
-        int offset = 0;
-        if (subscript == expectedSubscript && baseValue.isCell() && (baseValue.asCell()->structure() == it->cachedStructure()) && it->getOffset(index, offset)) {
-            callFrame->r(dst) = asObject(baseValue)->getDirectOffset(offset);
-            vPC += OPCODE_LENGTH(op_get_by_pname);
-            NEXT_INSTRUCTION();
-        }
-        Identifier propertyName(callFrame, subscript.toString(callFrame));
-        result = baseValue.get(callFrame, propertyName);
-        CHECK_FOR_EXCEPTION();
-        callFrame->r(dst) = result;
-        vPC += OPCODE_LENGTH(op_get_by_pname);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_get_by_val) {
-        /* get_by_val dst(r) base(r) property(r)
-
-           Converts register base to Object, gets the property named
-           by register property from the object, and puts the result
-           in register dst. property is nominally converted to string
-           but numbers are treated more efficiently.
-        */
-        int dst = vPC[1].u.operand;
-        int base = vPC[2].u.operand;
-        int property = vPC[3].u.operand;
-        
-        JSValue baseValue = callFrame->r(base).jsValue();
-        JSValue subscript = callFrame->r(property).jsValue();
-
-        JSValue result;
-
-        if (LIKELY(subscript.isUInt32())) {
-            uint32_t i = subscript.asUInt32();
-            if (isJSArray(globalData, baseValue)) {
-                JSArray* jsArray = asArray(baseValue);
-                if (jsArray->canGetIndex(i))
-                    result = jsArray->getIndex(i);
-                else
-                    result = jsArray->JSArray::get(callFrame, i);
-            } else if (isJSString(globalData, baseValue) && asString(baseValue)->canGetIndex(i))
-                result = asString(baseValue)->getIndex(callFrame, i);
-            else if (isJSByteArray(globalData, baseValue) && asByteArray(baseValue)->canAccessIndex(i))
-                result = asByteArray(baseValue)->getIndex(callFrame, i);
-            else
-                result = baseValue.get(callFrame, i);
-        } else {
-            Identifier property(callFrame, subscript.toString(callFrame));
-            result = baseValue.get(callFrame, property);
-        }
-
-        CHECK_FOR_EXCEPTION();
-        callFrame->r(dst) = result;
-        vPC += OPCODE_LENGTH(op_get_by_val);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_put_by_val) {
-        /* put_by_val base(r) property(r) value(r)
-
-           Sets register value on register base as the property named
-           by register property. Base is converted to object
-           first. register property is nominally converted to string
-           but numbers are treated more efficiently.
-
-           Unlike many opcodes, this one does not write any output to
-           the register file.
-        */
-        int base = vPC[1].u.operand;
-        int property = vPC[2].u.operand;
-        int value = vPC[3].u.operand;
-
-        JSValue baseValue = callFrame->r(base).jsValue();
-        JSValue subscript = callFrame->r(property).jsValue();
-
-        if (LIKELY(subscript.isUInt32())) {
-            uint32_t i = subscript.asUInt32();
-            if (isJSArray(globalData, baseValue)) {
-                JSArray* jsArray = asArray(baseValue);
-                if (jsArray->canSetIndex(i))
-                    jsArray->setIndex(i, callFrame->r(value).jsValue());
-                else
-                    jsArray->JSArray::put(callFrame, i, callFrame->r(value).jsValue());
-            } else if (isJSByteArray(globalData, baseValue) && asByteArray(baseValue)->canAccessIndex(i)) {
-                JSByteArray* jsByteArray = asByteArray(baseValue);
-                double dValue = 0;
-                JSValue jsValue = callFrame->r(value).jsValue();
-                if (jsValue.isInt32())
-                    jsByteArray->setIndex(i, jsValue.asInt32());
-                else if (jsValue.getNumber(dValue))
-                    jsByteArray->setIndex(i, dValue);
-                else
-                    baseValue.put(callFrame, i, jsValue);
-            } else
-                baseValue.put(callFrame, i, callFrame->r(value).jsValue());
-        } else {
-            Identifier property(callFrame, subscript.toString(callFrame));
-            if (!globalData->exception) { // Don't put to an object if toString threw an exception.
-                PutPropertySlot slot;
-                baseValue.put(callFrame, property, callFrame->r(value).jsValue(), slot);
-            }
-        }
-
-        CHECK_FOR_EXCEPTION();
-        vPC += OPCODE_LENGTH(op_put_by_val);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_del_by_val) {
-        /* del_by_val dst(r) base(r) property(r)
-
-           Converts register base to Object, deletes the property
-           named by register property from the object, and writes a
-           boolean indicating success (if true) or failure (if false)
-           to register dst.
-        */
-        int dst = vPC[1].u.operand;
-        int base = vPC[2].u.operand;
-        int property = vPC[3].u.operand;
-
-        JSObject* baseObj = callFrame->r(base).jsValue().toObject(callFrame); // may throw
-
-        JSValue subscript = callFrame->r(property).jsValue();
-        JSValue result;
-        uint32_t i;
-        if (subscript.getUInt32(i))
-            result = jsBoolean(baseObj->deleteProperty(callFrame, i));
-        else {
-            CHECK_FOR_EXCEPTION();
-            Identifier property(callFrame, subscript.toString(callFrame));
-            CHECK_FOR_EXCEPTION();
-            result = jsBoolean(baseObj->deleteProperty(callFrame, property));
-        }
-
-        CHECK_FOR_EXCEPTION();
-        callFrame->r(dst) = result;
-        vPC += OPCODE_LENGTH(op_del_by_val);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_put_by_index) {
-        /* put_by_index base(r) property(n) value(r)
-
-           Sets register value on register base as the property named
-           by the immediate number property. Base is converted to
-           object first.
-
-           Unlike many opcodes, this one does not write any output to
-           the register file.
-
-           This opcode is mainly used to initialize array literals.
-        */
-        int base = vPC[1].u.operand;
-        unsigned property = vPC[2].u.operand;
-        int value = vPC[3].u.operand;
-
-        callFrame->r(base).jsValue().put(callFrame, property, callFrame->r(value).jsValue());
-
-        vPC += OPCODE_LENGTH(op_put_by_index);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_loop) {
-        /* loop target(offset)
-         
-           Jumps unconditionally to offset target from the current
-           instruction.
-
-           Additionally this loop instruction may terminate JS execution is
-           the JS timeout is reached.
-         */
-#if ENABLE(OPCODE_STATS)
-        OpcodeStats::resetLastInstruction();
-#endif
-        int target = vPC[1].u.operand;
-        CHECK_FOR_TIMEOUT();
-        vPC += target;
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_jmp) {
-        /* jmp target(offset)
-
-           Jumps unconditionally to offset target from the current
-           instruction.
-        */
-#if ENABLE(OPCODE_STATS)
-        OpcodeStats::resetLastInstruction();
-#endif
-        int target = vPC[1].u.operand;
-
-        vPC += target;
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_loop_if_true) {
-        /* loop_if_true cond(r) target(offset)
-         
-           Jumps to offset target from the current instruction, if and
-           only if register cond converts to boolean as true.
-
-           Additionally this loop instruction may terminate JS execution is
-           the JS timeout is reached.
-         */
-        int cond = vPC[1].u.operand;
-        int target = vPC[2].u.operand;
-        if (callFrame->r(cond).jsValue().toBoolean(callFrame)) {
-            vPC += target;
-            CHECK_FOR_TIMEOUT();
-            NEXT_INSTRUCTION();
-        }
-        
-        vPC += OPCODE_LENGTH(op_loop_if_true);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_loop_if_false) {
-        /* loop_if_true cond(r) target(offset)
-         
-           Jumps to offset target from the current instruction, if and
-           only if register cond converts to boolean as false.
-
-           Additionally this loop instruction may terminate JS execution is
-           the JS timeout is reached.
-         */
-        int cond = vPC[1].u.operand;
-        int target = vPC[2].u.operand;
-        if (!callFrame->r(cond).jsValue().toBoolean(callFrame)) {
-            vPC += target;
-            CHECK_FOR_TIMEOUT();
-            NEXT_INSTRUCTION();
-        }
-        
-        vPC += OPCODE_LENGTH(op_loop_if_true);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_jtrue) {
-        /* jtrue cond(r) target(offset)
-
-           Jumps to offset target from the current instruction, if and
-           only if register cond converts to boolean as true.
-        */
-        int cond = vPC[1].u.operand;
-        int target = vPC[2].u.operand;
-        if (callFrame->r(cond).jsValue().toBoolean(callFrame)) {
-            vPC += target;
-            NEXT_INSTRUCTION();
-        }
-
-        vPC += OPCODE_LENGTH(op_jtrue);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_jfalse) {
-        /* jfalse cond(r) target(offset)
-
-           Jumps to offset target from the current instruction, if and
-           only if register cond converts to boolean as false.
-        */
-        int cond = vPC[1].u.operand;
-        int target = vPC[2].u.operand;
-        if (!callFrame->r(cond).jsValue().toBoolean(callFrame)) {
-            vPC += target;
-            NEXT_INSTRUCTION();
-        }
-
-        vPC += OPCODE_LENGTH(op_jfalse);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_jeq_null) {
-        /* jeq_null src(r) target(offset)
-
-           Jumps to offset target from the current instruction, if and
-           only if register src is null.
-        */
-        int src = vPC[1].u.operand;
-        int target = vPC[2].u.operand;
-        JSValue srcValue = callFrame->r(src).jsValue();
-
-        if (srcValue.isUndefinedOrNull() || (srcValue.isCell() && srcValue.asCell()->structure()->typeInfo().masqueradesAsUndefined())) {
-            vPC += target;
-            NEXT_INSTRUCTION();
-        }
-
-        vPC += OPCODE_LENGTH(op_jeq_null);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_jneq_null) {
-        /* jneq_null src(r) target(offset)
-
-           Jumps to offset target from the current instruction, if and
-           only if register src is not null.
-        */
-        int src = vPC[1].u.operand;
-        int target = vPC[2].u.operand;
-        JSValue srcValue = callFrame->r(src).jsValue();
-
-        if (!srcValue.isUndefinedOrNull() && (!srcValue.isCell() || !srcValue.asCell()->structure()->typeInfo().masqueradesAsUndefined())) {
-            vPC += target;
-            NEXT_INSTRUCTION();
-        }
-
-        vPC += OPCODE_LENGTH(op_jneq_null);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_jneq_ptr) {
-        /* jneq_ptr src(r) ptr(jsCell) target(offset)
-         
-           Jumps to offset target from the current instruction, if the value r is equal
-           to ptr, using pointer equality.
-         */
-        int src = vPC[1].u.operand;
-        JSValue ptr = JSValue(vPC[2].u.jsCell);
-        int target = vPC[3].u.operand;
-        JSValue srcValue = callFrame->r(src).jsValue();
-        if (srcValue != ptr) {
-            vPC += target;
-            NEXT_INSTRUCTION();
-        }
-
-        vPC += OPCODE_LENGTH(op_jneq_ptr);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_loop_if_less) {
-        /* loop_if_less src1(r) src2(r) target(offset)
-
-           Checks whether register src1 is less than register src2, as
-           with the ECMAScript '<' operator, and then jumps to offset
-           target from the current instruction, if and only if the 
-           result of the comparison is true.
-
-           Additionally this loop instruction may terminate JS execution is
-           the JS timeout is reached.
-         */
-        JSValue src1 = callFrame->r(vPC[1].u.operand).jsValue();
-        JSValue src2 = callFrame->r(vPC[2].u.operand).jsValue();
-        int target = vPC[3].u.operand;
-        
-        bool result = jsLess(callFrame, src1, src2);
-        CHECK_FOR_EXCEPTION();
-        
-        if (result) {
-            vPC += target;
-            CHECK_FOR_TIMEOUT();
-            NEXT_INSTRUCTION();
-        }
-        
-        vPC += OPCODE_LENGTH(op_loop_if_less);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_loop_if_lesseq) {
-        /* loop_if_lesseq src1(r) src2(r) target(offset)
-
-           Checks whether register src1 is less than or equal to register
-           src2, as with the ECMAScript '<=' operator, and then jumps to
-           offset target from the current instruction, if and only if the 
-           result of the comparison is true.
-
-           Additionally this loop instruction may terminate JS execution is
-           the JS timeout is reached.
-        */
-        JSValue src1 = callFrame->r(vPC[1].u.operand).jsValue();
-        JSValue src2 = callFrame->r(vPC[2].u.operand).jsValue();
-        int target = vPC[3].u.operand;
-        
-        bool result = jsLessEq(callFrame, src1, src2);
-        CHECK_FOR_EXCEPTION();
-        
-        if (result) {
-            vPC += target;
-            CHECK_FOR_TIMEOUT();
-            NEXT_INSTRUCTION();
-        }
-        
-        vPC += OPCODE_LENGTH(op_loop_if_lesseq);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_jnless) {
-        /* jnless src1(r) src2(r) target(offset)
-
-           Checks whether register src1 is less than register src2, as
-           with the ECMAScript '<' operator, and then jumps to offset
-           target from the current instruction, if and only if the 
-           result of the comparison is false.
-        */
-        JSValue src1 = callFrame->r(vPC[1].u.operand).jsValue();
-        JSValue src2 = callFrame->r(vPC[2].u.operand).jsValue();
-        int target = vPC[3].u.operand;
-
-        bool result = jsLess(callFrame, src1, src2);
-        CHECK_FOR_EXCEPTION();
-        
-        if (!result) {
-            vPC += target;
-            NEXT_INSTRUCTION();
-        }
-
-        vPC += OPCODE_LENGTH(op_jnless);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_jless) {
-        /* jless src1(r) src2(r) target(offset)
-
-           Checks whether register src1 is less than register src2, as
-           with the ECMAScript '<' operator, and then jumps to offset
-           target from the current instruction, if and only if the 
-           result of the comparison is true.
-        */
-        JSValue src1 = callFrame->r(vPC[1].u.operand).jsValue();
-        JSValue src2 = callFrame->r(vPC[2].u.operand).jsValue();
-        int target = vPC[3].u.operand;
-
-        bool result = jsLess(callFrame, src1, src2);
-        CHECK_FOR_EXCEPTION();
-        
-        if (result) {
-            vPC += target;
-            NEXT_INSTRUCTION();
-        }
-
-        vPC += OPCODE_LENGTH(op_jless);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_jnlesseq) {
-        /* jnlesseq src1(r) src2(r) target(offset)
-
-           Checks whether register src1 is less than or equal to
-           register src2, as with the ECMAScript '<=' operator,
-           and then jumps to offset target from the current instruction,
-           if and only if theresult of the comparison is false.
-        */
-        JSValue src1 = callFrame->r(vPC[1].u.operand).jsValue();
-        JSValue src2 = callFrame->r(vPC[2].u.operand).jsValue();
-        int target = vPC[3].u.operand;
-
-        bool result = jsLessEq(callFrame, src1, src2);
-        CHECK_FOR_EXCEPTION();
-        
-        if (!result) {
-            vPC += target;
-            NEXT_INSTRUCTION();
-        }
-
-        vPC += OPCODE_LENGTH(op_jnlesseq);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_switch_imm) {
-        /* switch_imm tableIndex(n) defaultOffset(offset) scrutinee(r)
-
-           Performs a range checked switch on the scrutinee value, using
-           the tableIndex-th immediate switch jump table.  If the scrutinee value
-           is an immediate number in the range covered by the referenced jump
-           table, and the value at jumpTable[scrutinee value] is non-zero, then
-           that value is used as the jump offset, otherwise defaultOffset is used.
-         */
-        int tableIndex = vPC[1].u.operand;
-        int defaultOffset = vPC[2].u.operand;
-        JSValue scrutinee = callFrame->r(vPC[3].u.operand).jsValue();
-        if (scrutinee.isInt32())
-            vPC += callFrame->codeBlock()->immediateSwitchJumpTable(tableIndex).offsetForValue(scrutinee.asInt32(), defaultOffset);
-        else {
-            double value;
-            int32_t intValue;
-            if (scrutinee.getNumber(value) && ((intValue = static_cast<int32_t>(value)) == value))
-                vPC += callFrame->codeBlock()->immediateSwitchJumpTable(tableIndex).offsetForValue(intValue, defaultOffset);
-            else
-                vPC += defaultOffset;
-        }
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_switch_char) {
-        /* switch_char tableIndex(n) defaultOffset(offset) scrutinee(r)
-
-           Performs a range checked switch on the scrutinee value, using
-           the tableIndex-th character switch jump table.  If the scrutinee value
-           is a single character string in the range covered by the referenced jump
-           table, and the value at jumpTable[scrutinee value] is non-zero, then
-           that value is used as the jump offset, otherwise defaultOffset is used.
-         */
-        int tableIndex = vPC[1].u.operand;
-        int defaultOffset = vPC[2].u.operand;
-        JSValue scrutinee = callFrame->r(vPC[3].u.operand).jsValue();
-        if (!scrutinee.isString())
-            vPC += defaultOffset;
-        else {
-            UString::Rep* value = asString(scrutinee)->value(callFrame).rep();
-            if (value->size() != 1)
-                vPC += defaultOffset;
-            else
-                vPC += callFrame->codeBlock()->characterSwitchJumpTable(tableIndex).offsetForValue(value->data()[0], defaultOffset);
-        }
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_switch_string) {
-        /* switch_string tableIndex(n) defaultOffset(offset) scrutinee(r)
-
-           Performs a sparse hashmap based switch on the value in the scrutinee
-           register, using the tableIndex-th string switch jump table.  If the 
-           scrutinee value is a string that exists as a key in the referenced 
-           jump table, then the value associated with the string is used as the 
-           jump offset, otherwise defaultOffset is used.
-         */
-        int tableIndex = vPC[1].u.operand;
-        int defaultOffset = vPC[2].u.operand;
-        JSValue scrutinee = callFrame->r(vPC[3].u.operand).jsValue();
-        if (!scrutinee.isString())
-            vPC += defaultOffset;
-        else 
-            vPC += callFrame->codeBlock()->stringSwitchJumpTable(tableIndex).offsetForValue(asString(scrutinee)->value(callFrame).rep(), defaultOffset);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_new_func) {
-        /* new_func dst(r) func(f)
-
-           Constructs a new Function instance from function func and
-           the current scope chain using the original Function
-           constructor, using the rules for function declarations, and
-           puts the result in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        int func = vPC[2].u.operand;
-
-        callFrame->r(dst) = JSValue(callFrame->codeBlock()->functionDecl(func)->make(callFrame, callFrame->scopeChain()));
-
-        vPC += OPCODE_LENGTH(op_new_func);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_new_func_exp) {
-        /* new_func_exp dst(r) func(f)
-
-           Constructs a new Function instance from function func and
-           the current scope chain using the original Function
-           constructor, using the rules for function expressions, and
-           puts the result in register dst.
-        */
-        int dst = vPC[1].u.operand;
-        int funcIndex = vPC[2].u.operand;
-
-        FunctionExecutable* function = callFrame->codeBlock()->functionExpr(funcIndex);
-        JSFunction* func = function->make(callFrame, callFrame->scopeChain());
-
-        /* 
-            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 = new (callFrame) JSStaticScopeObject(callFrame, function->name(), func, ReadOnly | DontDelete);
-            func->scope().push(functionScopeObject);
-        }
-
-        callFrame->r(dst) = JSValue(func);
-
-        vPC += OPCODE_LENGTH(op_new_func_exp);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_call_eval) {
-        /* call_eval dst(r) func(r) argCount(n) registerOffset(n)
-
-           Call a function named "eval" with no explicit "this" value
-           (which may therefore be the eval operator). If register
-           thisVal is the global object, and register func contains
-           that global object's original global eval function, then
-           perform the eval operator in local scope (interpreting
-           the argument registers as for the "call"
-           opcode). Otherwise, act exactly as the "call" opcode would.
-         */
-
-        int dst = vPC[1].u.operand;
-        int func = vPC[2].u.operand;
-        int argCount = vPC[3].u.operand;
-        int registerOffset = vPC[4].u.operand;
-
-        JSValue funcVal = callFrame->r(func).jsValue();
-
-        Register* newCallFrame = callFrame->registers() + registerOffset;
-        Register* argv = newCallFrame - RegisterFile::CallFrameHeaderSize - argCount;
-        JSValue thisValue = argv[0].jsValue();
-        JSGlobalObject* globalObject = callFrame->scopeChain()->globalObject;
-
-        if (thisValue == globalObject && funcVal == globalObject->evalFunction()) {
-            JSValue result = callEval(callFrame, registerFile, argv, argCount, registerOffset, exceptionValue);
-            if (exceptionValue)
-                goto vm_throw;
-            callFrame->r(dst) = result;
-
-            vPC += OPCODE_LENGTH(op_call_eval);
-            NEXT_INSTRUCTION();
-        }
-
-        // We didn't find the blessed version of eval, so process this
-        // instruction as a normal function call.
-        // fall through to op_call
-    }
-    DEFINE_OPCODE(op_call) {
-        /* call dst(r) func(r) argCount(n) registerOffset(n)
-
-           Perform a function call.
-           
-           registerOffset is the distance the callFrame pointer should move
-           before the VM initializes the new call frame's header.
-           
-           dst is where op_ret should store its result.
-         */
-
-        int dst = vPC[1].u.operand;
-        int func = vPC[2].u.operand;
-        int argCount = vPC[3].u.operand;
-        int registerOffset = vPC[4].u.operand;
-
-        JSValue v = callFrame->r(func).jsValue();
-
-        CallData callData;
-        CallType callType = v.getCallData(callData);
-
-        if (callType == CallTypeJS) {
-            ScopeChainNode* callDataScopeChain = callData.js.scopeChain;
-            CodeBlock* newCodeBlock = &callData.js.functionExecutable->bytecode(callFrame, callDataScopeChain);
-
-            CallFrame* previousCallFrame = callFrame;
-
-            callFrame = slideRegisterWindowForCall(newCodeBlock, registerFile, callFrame, registerOffset, argCount);
-            if (UNLIKELY(!callFrame)) {
-                callFrame = previousCallFrame;
-                exceptionValue = createStackOverflowError(callFrame);
-                goto vm_throw;
-            }
-
-            callFrame->init(newCodeBlock, vPC + 5, callDataScopeChain, previousCallFrame, dst, argCount, asFunction(v));
-            vPC = newCodeBlock->instructions().begin();
-
-#if ENABLE(OPCODE_STATS)
-            OpcodeStats::resetLastInstruction();
-#endif
-
-            NEXT_INSTRUCTION();
-        }
-
-        if (callType == CallTypeHost) {
-            ScopeChainNode* scopeChain = callFrame->scopeChain();
-            CallFrame* newCallFrame = CallFrame::create(callFrame->registers() + registerOffset);
-            newCallFrame->init(0, vPC + 5, scopeChain, callFrame, dst, argCount, 0);
-
-            Register* thisRegister = newCallFrame->registers() - RegisterFile::CallFrameHeaderSize - argCount;
-            ArgList args(thisRegister + 1, argCount - 1);
-
-            // FIXME: All host methods should be calling toThisObject, but this is not presently the case.
-            JSValue thisValue = thisRegister->jsValue();
-            if (thisValue == jsNull())
-                thisValue = callFrame->globalThisValue();
-
-            JSValue returnValue;
-            {
-                SamplingTool::HostCallRecord callRecord(m_sampler.get());
-                returnValue = callData.native.function(newCallFrame, asObject(v), thisValue, args);
-            }
-            CHECK_FOR_EXCEPTION();
-
-            callFrame->r(dst) = returnValue;
-
-            vPC += OPCODE_LENGTH(op_call);
-            NEXT_INSTRUCTION();
-        }
-
-        ASSERT(callType == CallTypeNone);
-
-        exceptionValue = createNotAFunctionError(callFrame, v, vPC - callFrame->codeBlock()->instructions().begin(), callFrame->codeBlock());
-        goto vm_throw;
-    }
-    DEFINE_OPCODE(op_load_varargs) {
-        int argCountDst = vPC[1].u.operand;
-        int argsOffset = vPC[2].u.operand;
-        
-        JSValue arguments = callFrame->r(argsOffset).jsValue();
-        uint32_t argCount = 0;
-        if (!arguments) {
-            argCount = (uint32_t)(callFrame->argumentCount()) - 1;
-            argCount = min<uint32_t>(argCount, Arguments::MaxArguments);
-            int32_t sizeDelta = argsOffset + argCount + RegisterFile::CallFrameHeaderSize;
-            Register* newEnd = callFrame->registers() + sizeDelta;
-            if (!registerFile->grow(newEnd) || ((newEnd - callFrame->registers()) != sizeDelta)) {
-                exceptionValue = createStackOverflowError(callFrame);
-                goto vm_throw;
-            }
-            ASSERT(!callFrame->callee()->isHostFunction());
-            uint32_t expectedParams = callFrame->callee()->jsExecutable()->parameterCount();
-            uint32_t inplaceArgs = min(argCount, expectedParams);
-            uint32_t i = 0;
-            Register* argStore = callFrame->registers() + argsOffset;
-
-            // First step is to copy the "expected" parameters from their normal location relative to the callframe
-            for (; i < inplaceArgs; i++)
-                argStore[i] = callFrame->registers()[i - RegisterFile::CallFrameHeaderSize - expectedParams];
-            // Then we copy any additional arguments that may be further up the stack ('-1' to account for 'this')
-            for (; i < argCount; i++)
-                argStore[i] = callFrame->registers()[i - RegisterFile::CallFrameHeaderSize - expectedParams - argCount - 1];
-        } else if (!arguments.isUndefinedOrNull()) {
-            if (!arguments.isObject()) {
-                exceptionValue = createInvalidParamError(callFrame, "Function.prototype.apply", arguments, vPC - callFrame->codeBlock()->instructions().begin(), callFrame->codeBlock());
-                goto vm_throw;
-            }
-            if (asObject(arguments)->classInfo() == &Arguments::info) {
-                Arguments* args = asArguments(arguments);
-                argCount = args->numProvidedArguments(callFrame);
-                argCount = min<uint32_t>(argCount, Arguments::MaxArguments);
-                int32_t sizeDelta = argsOffset + argCount + RegisterFile::CallFrameHeaderSize;
-                Register* newEnd = callFrame->registers() + sizeDelta;
-                if (!registerFile->grow(newEnd) || ((newEnd - callFrame->registers()) != sizeDelta)) {
-                    exceptionValue = createStackOverflowError(callFrame);
-                    goto vm_throw;
-                }
-                args->copyToRegisters(callFrame, callFrame->registers() + argsOffset, argCount);
-            } else if (isJSArray(&callFrame->globalData(), arguments)) {
-                JSArray* array = asArray(arguments);
-                argCount = array->length();
-                argCount = min<uint32_t>(argCount, Arguments::MaxArguments);
-                int32_t sizeDelta = argsOffset + argCount + RegisterFile::CallFrameHeaderSize;
-                Register* newEnd = callFrame->registers() + sizeDelta;
-                if (!registerFile->grow(newEnd) || ((newEnd - callFrame->registers()) != sizeDelta)) {
-                    exceptionValue = createStackOverflowError(callFrame);
-                    goto vm_throw;
-                }
-                array->copyToRegisters(callFrame, callFrame->registers() + argsOffset, argCount);
-            } else if (asObject(arguments)->inherits(&JSArray::info)) {
-                JSObject* argObject = asObject(arguments);
-                argCount = argObject->get(callFrame, callFrame->propertyNames().length).toUInt32(callFrame);
-                argCount = min<uint32_t>(argCount, Arguments::MaxArguments);
-                int32_t sizeDelta = argsOffset + argCount + RegisterFile::CallFrameHeaderSize;
-                Register* newEnd = callFrame->registers() + sizeDelta;
-                if (!registerFile->grow(newEnd) || ((newEnd - callFrame->registers()) != sizeDelta)) {
-                    exceptionValue = createStackOverflowError(callFrame);
-                    goto vm_throw;
-                }
-                Register* argsBuffer = callFrame->registers() + argsOffset;
-                for (uint32_t i = 0; i < argCount; ++i) {
-                    argsBuffer[i] = asObject(arguments)->get(callFrame, i);
-                    CHECK_FOR_EXCEPTION();
-                }
-            } else {
-                if (!arguments.isObject()) {
-                    exceptionValue = createInvalidParamError(callFrame, "Function.prototype.apply", arguments, vPC - callFrame->codeBlock()->instructions().begin(), callFrame->codeBlock());
-                    goto vm_throw;
-                }
-            }
-        }
-        CHECK_FOR_EXCEPTION();
-        callFrame->r(argCountDst) = Register::withInt(argCount + 1);
-        vPC += OPCODE_LENGTH(op_load_varargs);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_call_varargs) {
-        /* call_varargs dst(r) func(r) argCountReg(r) baseRegisterOffset(n)
-         
-         Perform a function call with a dynamic set of arguments.
-         
-         registerOffset is the distance the callFrame pointer should move
-         before the VM initializes the new call frame's header, excluding
-         space for arguments.
-         
-         dst is where op_ret should store its result.
-         */
-        
-        int dst = vPC[1].u.operand;
-        int func = vPC[2].u.operand;
-        int argCountReg = vPC[3].u.operand;
-        int registerOffset = vPC[4].u.operand;
-        
-        JSValue v = callFrame->r(func).jsValue();
-        int argCount = callFrame->r(argCountReg).i();
-        registerOffset += argCount;
-        CallData callData;
-        CallType callType = v.getCallData(callData);
-        
-        if (callType == CallTypeJS) {
-            ScopeChainNode* callDataScopeChain = callData.js.scopeChain;
-            CodeBlock* newCodeBlock = &callData.js.functionExecutable->bytecode(callFrame, callDataScopeChain);
-            
-            CallFrame* previousCallFrame = callFrame;
-            
-            callFrame = slideRegisterWindowForCall(newCodeBlock, registerFile, callFrame, registerOffset, argCount);
-            if (UNLIKELY(!callFrame)) {
-                callFrame = previousCallFrame;
-                exceptionValue = createStackOverflowError(callFrame);
-                goto vm_throw;
-            }
-            
-            callFrame->init(newCodeBlock, vPC + 5, callDataScopeChain, previousCallFrame, dst, argCount, asFunction(v));
-            vPC = newCodeBlock->instructions().begin();
-            
-#if ENABLE(OPCODE_STATS)
-            OpcodeStats::resetLastInstruction();
-#endif
-            
-            NEXT_INSTRUCTION();
-        }
-        
-        if (callType == CallTypeHost) {
-            ScopeChainNode* scopeChain = callFrame->scopeChain();
-            CallFrame* newCallFrame = CallFrame::create(callFrame->registers() + registerOffset);
-            newCallFrame->init(0, vPC + 5, scopeChain, callFrame, dst, argCount, 0);
-            
-            Register* thisRegister = newCallFrame->registers() - RegisterFile::CallFrameHeaderSize - argCount;
-            ArgList args(thisRegister + 1, argCount - 1);
-            
-            // FIXME: All host methods should be calling toThisObject, but this is not presently the case.
-            JSValue thisValue = thisRegister->jsValue();
-            if (thisValue == jsNull())
-                thisValue = callFrame->globalThisValue();
-            
-            JSValue returnValue;
-            {
-                SamplingTool::HostCallRecord callRecord(m_sampler.get());
-                returnValue = callData.native.function(newCallFrame, asObject(v), thisValue, args);
-            }
-            CHECK_FOR_EXCEPTION();
-            
-            callFrame->r(dst) = returnValue;
-            
-            vPC += OPCODE_LENGTH(op_call_varargs);
-            NEXT_INSTRUCTION();
-        }
-        
-        ASSERT(callType == CallTypeNone);
-        
-        exceptionValue = createNotAFunctionError(callFrame, v, vPC - callFrame->codeBlock()->instructions().begin(), callFrame->codeBlock());
-        goto vm_throw;
-    }
-    DEFINE_OPCODE(op_tear_off_activation) {
-        /* tear_off_activation activation(r)
-
-           Copy all locals and parameters to new memory allocated on
-           the heap, and make the passed activation use this memory
-           in the future when looking up entries in the symbol table.
-           If there is an 'arguments' object, then it will also use
-           this memory for storing the named parameters, but not any
-           extra arguments.
-
-           This opcode should only be used immediately before op_ret.
-        */
-
-        int src = vPC[1].u.operand;
-        ASSERT(callFrame->codeBlock()->needsFullScopeChain());
-
-        asActivation(callFrame->r(src).jsValue())->copyRegisters(callFrame->optionalCalleeArguments());
-
-        vPC += OPCODE_LENGTH(op_tear_off_activation);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_tear_off_arguments) {
-        /* tear_off_arguments
-
-           Copy all arguments to new memory allocated on the heap,
-           and make the 'arguments' object use this memory in the
-           future when looking up named parameters, but not any
-           extra arguments. If an activation object exists for the
-           current function context, then the tear_off_activation
-           opcode should be used instead.
-
-           This opcode should only be used immediately before op_ret.
-        */
-
-        ASSERT(callFrame->codeBlock()->usesArguments() && !callFrame->codeBlock()->needsFullScopeChain());
-
-        if (callFrame->optionalCalleeArguments())
-            callFrame->optionalCalleeArguments()->copyRegisters();
-
-        vPC += OPCODE_LENGTH(op_tear_off_arguments);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_ret) {
-        /* ret result(r)
-           
-           Return register result as the return value of the current
-           function call, writing it into the caller's expected return
-           value register. In addition, unwind one call frame and
-           restore the scope chain, code block instruction pointer and
-           register base to those of the calling function.
-        */
-
-        int result = vPC[1].u.operand;
-
-        if (callFrame->codeBlock()->needsFullScopeChain())
-            callFrame->scopeChain()->deref();
-
-        JSValue returnValue = callFrame->r(result).jsValue();
-
-        vPC = callFrame->returnPC();
-        int dst = callFrame->returnValueRegister();
-        callFrame = callFrame->callerFrame();
-        
-        if (callFrame->hasHostCallFrameFlag())
-            return returnValue;
-
-        callFrame->r(dst) = returnValue;
-
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_enter) {
-        /* enter
-
-           Initializes local variables to undefined and fills constant
-           registers with their values. If the code block requires an
-           activation, enter_with_activation should be used instead.
-
-           This opcode should only be used at the beginning of a code
-           block.
-        */
-
-        size_t i = 0;
-        CodeBlock* codeBlock = callFrame->codeBlock();
-        
-        for (size_t count = codeBlock->m_numVars; i < count; ++i)
-            callFrame->r(i) = jsUndefined();
-
-        vPC += OPCODE_LENGTH(op_enter);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_enter_with_activation) {
-        /* enter_with_activation dst(r)
-
-           Initializes local variables to undefined, fills constant
-           registers with their values, creates an activation object,
-           and places the new activation both in dst and at the top
-           of the scope chain. If the code block does not require an
-           activation, enter should be used instead.
-
-           This opcode should only be used at the beginning of a code
-           block.
-        */
-
-        size_t i = 0;
-        CodeBlock* codeBlock = callFrame->codeBlock();
-
-        for (size_t count = codeBlock->m_numVars; i < count; ++i)
-            callFrame->r(i) = jsUndefined();
-
-        int dst = vPC[1].u.operand;
-        JSActivation* activation = new (globalData) JSActivation(callFrame, static_cast<FunctionExecutable*>(codeBlock->ownerExecutable()));
-        callFrame->r(dst) = JSValue(activation);
-        callFrame->setScopeChain(callFrame->scopeChain()->copy()->push(activation));
-
-        vPC += OPCODE_LENGTH(op_enter_with_activation);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_convert_this) {
-        /* convert_this this(r)
-
-           Takes the value in the 'this' register, converts it to a
-           value that is suitable for use as the 'this' value, and
-           stores it in the 'this' register. This opcode is emitted
-           to avoid doing the conversion in the caller unnecessarily.
-
-           This opcode should only be used at the beginning of a code
-           block.
-        */
-
-        int thisRegister = vPC[1].u.operand;
-        JSValue thisVal = callFrame->r(thisRegister).jsValue();
-        if (thisVal.needsThisConversion())
-            callFrame->r(thisRegister) = JSValue(thisVal.toThisObject(callFrame));
-
-        vPC += OPCODE_LENGTH(op_convert_this);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_init_arguments) {
-        /* create_arguments
-
-           Initialises the arguments object reference to null to ensure
-           we can correctly detect that we need to create it later (or
-           avoid creating it altogether).
-
-           This opcode should only be used at the beginning of a code
-           block.
-         */
-        callFrame->r(RegisterFile::ArgumentsRegister) = JSValue();
-        vPC += OPCODE_LENGTH(op_init_arguments);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_create_arguments) {
-        /* create_arguments
-
-           Creates the 'arguments' object and places it in both the
-           'arguments' call frame slot and the local 'arguments'
-           register, if it has not already been initialised.
-         */
-        
-         if (!callFrame->r(RegisterFile::ArgumentsRegister).jsValue()) {
-             Arguments* arguments = new (globalData) Arguments(callFrame);
-             callFrame->setCalleeArguments(arguments);
-             callFrame->r(RegisterFile::ArgumentsRegister) = JSValue(arguments);
-         }
-        vPC += OPCODE_LENGTH(op_create_arguments);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_construct) {
-        /* construct dst(r) func(r) argCount(n) registerOffset(n) proto(r) thisRegister(r)
-
-           Invoke register "func" as a constructor. For JS
-           functions, the calling convention is exactly as for the
-           "call" opcode, except that the "this" value is a newly
-           created Object. For native constructors, no "this"
-           value is passed. In either case, the argCount and registerOffset
-           registers are interpreted as for the "call" opcode.
-
-           Register proto must contain the prototype property of
-           register func. This is to enable polymorphic inline
-           caching of this lookup.
-        */
-
-        int dst = vPC[1].u.operand;
-        int func = vPC[2].u.operand;
-        int argCount = vPC[3].u.operand;
-        int registerOffset = vPC[4].u.operand;
-        int proto = vPC[5].u.operand;
-        int thisRegister = vPC[6].u.operand;
-
-        JSValue v = callFrame->r(func).jsValue();
-
-        ConstructData constructData;
-        ConstructType constructType = v.getConstructData(constructData);
-
-        if (constructType == ConstructTypeJS) {
-            ScopeChainNode* callDataScopeChain = constructData.js.scopeChain;
-            CodeBlock* newCodeBlock = &constructData.js.functionExecutable->bytecode(callFrame, callDataScopeChain);
-
-            Structure* structure;
-            JSValue prototype = callFrame->r(proto).jsValue();
-            if (prototype.isObject())
-                structure = asObject(prototype)->inheritorID();
-            else
-                structure = callDataScopeChain->globalObject->emptyObjectStructure();
-            JSObject* newObject = new (globalData) JSObject(structure);
-
-            callFrame->r(thisRegister) = JSValue(newObject); // "this" value
-
-            CallFrame* previousCallFrame = callFrame;
-
-            callFrame = slideRegisterWindowForCall(newCodeBlock, registerFile, callFrame, registerOffset, argCount);
-            if (UNLIKELY(!callFrame)) {
-                callFrame = previousCallFrame;
-                exceptionValue = createStackOverflowError(callFrame);
-                goto vm_throw;
-            }
-
-            callFrame->init(newCodeBlock, vPC + 7, callDataScopeChain, previousCallFrame, dst, argCount, asFunction(v));
-            vPC = newCodeBlock->instructions().begin();
-
-#if ENABLE(OPCODE_STATS)
-            OpcodeStats::resetLastInstruction();
-#endif
-
-            NEXT_INSTRUCTION();
-        }
-
-        if (constructType == ConstructTypeHost) {
-            ArgList args(callFrame->registers() + thisRegister + 1, argCount - 1);
-
-            ScopeChainNode* scopeChain = callFrame->scopeChain();
-            CallFrame* newCallFrame = CallFrame::create(callFrame->registers() + registerOffset);
-            newCallFrame->init(0, vPC + 7, scopeChain, callFrame, dst, argCount, 0);
-
-            JSValue returnValue;
-            {
-                SamplingTool::HostCallRecord callRecord(m_sampler.get());
-                returnValue = constructData.native.function(newCallFrame, asObject(v), args);
-            }
-            CHECK_FOR_EXCEPTION();
-            callFrame->r(dst) = JSValue(returnValue);
-
-            vPC += OPCODE_LENGTH(op_construct);
-            NEXT_INSTRUCTION();
-        }
-
-        ASSERT(constructType == ConstructTypeNone);
-
-        exceptionValue = createNotAConstructorError(callFrame, v, vPC - callFrame->codeBlock()->instructions().begin(), callFrame->codeBlock());
-        goto vm_throw;
-    }
-    DEFINE_OPCODE(op_construct_verify) {
-        /* construct_verify dst(r) override(r)
-
-           Verifies that register dst holds an object. If not, moves
-           the object in register override to register dst.
-        */
-
-        int dst = vPC[1].u.operand;
-        if (LIKELY(callFrame->r(dst).jsValue().isObject())) {
-            vPC += OPCODE_LENGTH(op_construct_verify);
-            NEXT_INSTRUCTION();
-        }
-
-        int override = vPC[2].u.operand;
-        callFrame->r(dst) = callFrame->r(override);
-
-        vPC += OPCODE_LENGTH(op_construct_verify);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_strcat) {
-        int dst = vPC[1].u.operand;
-        int src = vPC[2].u.operand;
-        int count = vPC[3].u.operand;
-
-        callFrame->r(dst) = jsString(callFrame, &callFrame->registers()[src], count);
-        CHECK_FOR_EXCEPTION();
-        vPC += OPCODE_LENGTH(op_strcat);
-
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_to_primitive) {
-        int dst = vPC[1].u.operand;
-        int src = vPC[2].u.operand;
-
-        callFrame->r(dst) = callFrame->r(src).jsValue().toPrimitive(callFrame);
-        vPC += OPCODE_LENGTH(op_to_primitive);
-
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_push_scope) {
-        /* push_scope scope(r)
-
-           Converts register scope to object, and pushes it onto the top
-           of the current scope chain.  The contents of the register scope
-           are replaced by the result of toObject conversion of the scope.
-        */
-        int scope = vPC[1].u.operand;
-        JSValue v = callFrame->r(scope).jsValue();
-        JSObject* o = v.toObject(callFrame);
-        CHECK_FOR_EXCEPTION();
-
-        callFrame->r(scope) = JSValue(o);
-        callFrame->setScopeChain(callFrame->scopeChain()->push(o));
-
-        vPC += OPCODE_LENGTH(op_push_scope);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_pop_scope) {
-        /* pop_scope
-
-           Removes the top item from the current scope chain.
-        */
-        callFrame->setScopeChain(callFrame->scopeChain()->pop());
-
-        vPC += OPCODE_LENGTH(op_pop_scope);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_get_pnames) {
-        /* get_pnames dst(r) base(r) i(n) size(n) breakTarget(offset)
-
-           Creates a property name list for register base and puts it
-           in register dst, initializing i and size for iteration. If
-           base is undefined or null, jumps to breakTarget.
-        */
-        int dst = vPC[1].u.operand;
-        int base = vPC[2].u.operand;
-        int i = vPC[3].u.operand;
-        int size = vPC[4].u.operand;
-        int breakTarget = vPC[5].u.operand;
-
-        JSValue v = callFrame->r(base).jsValue();
-        if (v.isUndefinedOrNull()) {
-            vPC += breakTarget;
-            NEXT_INSTRUCTION();
-        }
-
-        JSObject* o = v.toObject(callFrame);
-        Structure* structure = o->structure();
-        JSPropertyNameIterator* jsPropertyNameIterator = structure->enumerationCache();
-        if (!jsPropertyNameIterator || jsPropertyNameIterator->cachedPrototypeChain() != structure->prototypeChain(callFrame))
-            jsPropertyNameIterator = JSPropertyNameIterator::create(callFrame, o);
-
-        callFrame->r(dst) = jsPropertyNameIterator;
-        callFrame->r(base) = JSValue(o);
-        callFrame->r(i) = Register::withInt(0);
-        callFrame->r(size) = Register::withInt(jsPropertyNameIterator->size());
-        vPC += OPCODE_LENGTH(op_get_pnames);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_next_pname) {
-        /* next_pname dst(r) base(r) i(n) size(n) iter(r) target(offset)
-
-           Copies the next name from the property name list in
-           register iter to dst, then jumps to offset target. If there are no
-           names left, invalidates the iterator and continues to the next
-           instruction.
-        */
-        int dst = vPC[1].u.operand;
-        int base = vPC[2].u.operand;
-        int i = vPC[3].u.operand;
-        int size = vPC[4].u.operand;
-        int iter = vPC[5].u.operand;
-        int target = vPC[6].u.operand;
-
-        JSPropertyNameIterator* it = callFrame->r(iter).propertyNameIterator();
-        while (callFrame->r(i).i() != callFrame->r(size).i()) {
-            JSValue key = it->get(callFrame, asObject(callFrame->r(base).jsValue()), callFrame->r(i).i());
-            callFrame->r(i) = Register::withInt(callFrame->r(i).i() + 1);
-            if (key) {
-                CHECK_FOR_TIMEOUT();
-                callFrame->r(dst) = key;
-                vPC += target;
-                NEXT_INSTRUCTION();
-            }
-        }
-
-        vPC += OPCODE_LENGTH(op_next_pname);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_jmp_scopes) {
-        /* jmp_scopes count(n) target(offset)
-
-           Removes the a number of items from the current scope chain
-           specified by immediate number count, then jumps to offset
-           target.
-        */
-        int count = vPC[1].u.operand;
-        int target = vPC[2].u.operand;
-
-        ScopeChainNode* tmp = callFrame->scopeChain();
-        while (count--)
-            tmp = tmp->pop();
-        callFrame->setScopeChain(tmp);
-
-        vPC += target;
-        NEXT_INSTRUCTION();
-    }
-#if HAVE(COMPUTED_GOTO)
-    // Appease GCC
-    goto *(&&skip_new_scope);
-#endif
-    DEFINE_OPCODE(op_push_new_scope) {
-        /* new_scope dst(r) property(id) value(r)
-         
-           Constructs a new StaticScopeObject with property set to value.  That scope
-           object is then pushed onto the ScopeChain.  The scope object is then stored
-           in dst for GC.
-         */
-        callFrame->setScopeChain(createExceptionScope(callFrame, vPC));
-
-        vPC += OPCODE_LENGTH(op_push_new_scope);
-        NEXT_INSTRUCTION();
-    }
-#if HAVE(COMPUTED_GOTO)
-    skip_new_scope:
-#endif
-    DEFINE_OPCODE(op_catch) {
-        /* catch ex(r)
-
-           Retrieves the VM's current exception and puts it in register
-           ex. This is only valid after an exception has been raised,
-           and usually forms the beginning of an exception handler.
-        */
-        ASSERT(exceptionValue);
-        ASSERT(!globalData->exception);
-        int ex = vPC[1].u.operand;
-        callFrame->r(ex) = exceptionValue;
-        exceptionValue = JSValue();
-
-        vPC += OPCODE_LENGTH(op_catch);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_throw) {
-        /* throw ex(r)
-
-           Throws register ex as an exception. This involves three
-           steps: first, it is set as the current exception in the
-           VM's internal state, then the stack is unwound until an
-           exception handler or a native code boundary is found, and
-           then control resumes at the exception handler if any or
-           else the script returns control to the nearest native caller.
-        */
-
-        int ex = vPC[1].u.operand;
-        exceptionValue = callFrame->r(ex).jsValue();
-
-        handler = throwException(callFrame, exceptionValue, vPC - callFrame->codeBlock()->instructions().begin(), true);
-        if (!handler) {
-            *exception = exceptionValue;
-            return jsNull();
-        }
-
-        vPC = callFrame->codeBlock()->instructions().begin() + handler->target;
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_new_error) {
-        /* new_error dst(r) type(n) message(k)
-
-           Constructs a new Error instance using the original
-           constructor, using immediate number n as the type and
-           constant message as the message string. The result is
-           written to register dst.
-        */
-        int dst = vPC[1].u.operand;
-        int type = vPC[2].u.operand;
-        int message = vPC[3].u.operand;
-
-        CodeBlock* codeBlock = callFrame->codeBlock();
-        callFrame->r(dst) = JSValue(Error::create(callFrame, (ErrorType)type, callFrame->r(message).jsValue().toString(callFrame), codeBlock->lineNumberForBytecodeOffset(callFrame, vPC - codeBlock->instructions().begin()), codeBlock->ownerExecutable()->sourceID(), codeBlock->ownerExecutable()->sourceURL()));
-
-        vPC += OPCODE_LENGTH(op_new_error);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_end) {
-        /* end result(r)
-           
-           Return register result as the value of a global or eval
-           program. Return control to the calling native code.
-        */
-
-        if (callFrame->codeBlock()->needsFullScopeChain()) {
-            ScopeChainNode* scopeChain = callFrame->scopeChain();
-            ASSERT(scopeChain->refCount > 1);
-            scopeChain->deref();
-        }
-        int result = vPC[1].u.operand;
-        return callFrame->r(result).jsValue();
-    }
-    DEFINE_OPCODE(op_put_getter) {
-        /* put_getter base(r) property(id) function(r)
-
-           Sets register function on register base as the getter named
-           by identifier property. Base and function are assumed to be
-           objects as this op should only be used for getters defined
-           in object literal form.
-
-           Unlike many opcodes, this one does not write any output to
-           the register file.
-        */
-        int base = vPC[1].u.operand;
-        int property = vPC[2].u.operand;
-        int function = vPC[3].u.operand;
-
-        ASSERT(callFrame->r(base).jsValue().isObject());
-        JSObject* baseObj = asObject(callFrame->r(base).jsValue());
-        Identifier& ident = callFrame->codeBlock()->identifier(property);
-        ASSERT(callFrame->r(function).jsValue().isObject());
-        baseObj->defineGetter(callFrame, ident, asObject(callFrame->r(function).jsValue()));
-
-        vPC += OPCODE_LENGTH(op_put_getter);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_put_setter) {
-        /* put_setter base(r) property(id) function(r)
-
-           Sets register function on register base as the setter named
-           by identifier property. Base and function are assumed to be
-           objects as this op should only be used for setters defined
-           in object literal form.
-
-           Unlike many opcodes, this one does not write any output to
-           the register file.
-        */
-        int base = vPC[1].u.operand;
-        int property = vPC[2].u.operand;
-        int function = vPC[3].u.operand;
-
-        ASSERT(callFrame->r(base).jsValue().isObject());
-        JSObject* baseObj = asObject(callFrame->r(base).jsValue());
-        Identifier& ident = callFrame->codeBlock()->identifier(property);
-        ASSERT(callFrame->r(function).jsValue().isObject());
-        baseObj->defineSetter(callFrame, ident, asObject(callFrame->r(function).jsValue()), 0);
-
-        vPC += OPCODE_LENGTH(op_put_setter);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_method_check) {
-        vPC++;
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_jsr) {
-        /* jsr retAddrDst(r) target(offset)
-
-           Places the address of the next instruction into the retAddrDst
-           register and jumps to offset target from the current instruction.
-        */
-        int retAddrDst = vPC[1].u.operand;
-        int target = vPC[2].u.operand;
-        callFrame->r(retAddrDst) = vPC + OPCODE_LENGTH(op_jsr);
-
-        vPC += target;
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_sret) {
-        /* sret retAddrSrc(r)
-
-         Jumps to the address stored in the retAddrSrc register. This
-         differs from op_jmp because the target address is stored in a
-         register, not as an immediate.
-        */
-        int retAddrSrc = vPC[1].u.operand;
-        vPC = callFrame->r(retAddrSrc).vPC();
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_debug) {
-        /* debug debugHookID(n) firstLine(n) lastLine(n)
-
-         Notifies the debugger of the current state of execution. This opcode
-         is only generated while the debugger is attached.
-        */
-        int debugHookID = vPC[1].u.operand;
-        int firstLine = vPC[2].u.operand;
-        int lastLine = vPC[3].u.operand;
-
-        debug(callFrame, static_cast<DebugHookID>(debugHookID), firstLine, lastLine);
-
-        vPC += OPCODE_LENGTH(op_debug);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_profile_will_call) {
-        /* op_profile_will_call function(r)
-
-         Notifies the profiler of the beginning of a function call. This opcode
-         is only generated if developer tools are enabled.
-        */
-        int function = vPC[1].u.operand;
-
-        if (*enabledProfilerReference)
-            (*enabledProfilerReference)->willExecute(callFrame, callFrame->r(function).jsValue());
-
-        vPC += OPCODE_LENGTH(op_profile_will_call);
-        NEXT_INSTRUCTION();
-    }
-    DEFINE_OPCODE(op_profile_did_call) {
-        /* op_profile_did_call function(r)
-
-         Notifies the profiler of the end of a function call. This opcode
-         is only generated if developer tools are enabled.
-        */
-        int function = vPC[1].u.operand;
-
-        if (*enabledProfilerReference)
-            (*enabledProfilerReference)->didExecute(callFrame, callFrame->r(function).jsValue());
-
-        vPC += OPCODE_LENGTH(op_profile_did_call);
-        NEXT_INSTRUCTION();
-    }
-    vm_throw: {
-        globalData->exception = JSValue();
-        if (!tickCount) {
-            // The exceptionValue is a lie! (GCC produces bad code for reasons I 
-            // cannot fathom if we don't assign to the exceptionValue before branching)
-            exceptionValue = createInterruptedExecutionException(globalData);
-        }
-        handler = throwException(callFrame, exceptionValue, vPC - callFrame->codeBlock()->instructions().begin(), false);
-        if (!handler) {
-            *exception = exceptionValue;
-            return jsNull();
-        }
-
-        vPC = callFrame->codeBlock()->instructions().begin() + handler->target;
-        NEXT_INSTRUCTION();
-    }
-    }
-#if !HAVE(COMPUTED_GOTO)
-    } // iterator loop ends
-#endif
-#endif // USE(INTERPRETER)
-    #undef NEXT_INSTRUCTION
-    #undef DEFINE_OPCODE
-    #undef CHECK_FOR_EXCEPTION
-    #undef CHECK_FOR_TIMEOUT
-}
-
-JSValue Interpreter::retrieveArguments(CallFrame* callFrame, JSFunction* function) const
-{
-    CallFrame* functionCallFrame = findFunctionCallFrame(callFrame, function);
-    if (!functionCallFrame)
-        return jsNull();
-
-    CodeBlock* codeBlock = functionCallFrame->codeBlock();
-    if (codeBlock->usesArguments()) {
-        ASSERT(codeBlock->codeType() == FunctionCode);
-        SymbolTable& symbolTable = *codeBlock->symbolTable();
-        int argumentsIndex = symbolTable.get(functionCallFrame->propertyNames().arguments.ustring().rep()).getIndex();
-        if (!functionCallFrame->r(argumentsIndex).jsValue()) {
-            Arguments* arguments = new (callFrame) Arguments(functionCallFrame);
-            functionCallFrame->setCalleeArguments(arguments);
-            functionCallFrame->r(RegisterFile::ArgumentsRegister) = JSValue(arguments);
-        }
-        return functionCallFrame->r(argumentsIndex).jsValue();
-    }
-
-    Arguments* arguments = functionCallFrame->optionalCalleeArguments();
-    if (!arguments) {
-        arguments = new (functionCallFrame) Arguments(functionCallFrame);
-        arguments->copyRegisters();
-        callFrame->setCalleeArguments(arguments);
-    }
-
-    return arguments;
-}
-
-JSValue Interpreter::retrieveCaller(CallFrame* callFrame, InternalFunction* function) const
-{
-    CallFrame* functionCallFrame = findFunctionCallFrame(callFrame, function);
-    if (!functionCallFrame)
-        return jsNull();
-
-    CallFrame* callerFrame = functionCallFrame->callerFrame();
-    if (callerFrame->hasHostCallFrameFlag())
-        return jsNull();
-
-    JSValue caller = callerFrame->callee();
-    if (!caller)
-        return jsNull();
-
-    return caller;
-}
-
-void Interpreter::retrieveLastCaller(CallFrame* callFrame, int& lineNumber, intptr_t& sourceID, UString& sourceURL, JSValue& function) const
-{
-    function = JSValue();
-    lineNumber = -1;
-    sourceURL = UString();
-
-    CallFrame* callerFrame = callFrame->callerFrame();
-    if (callerFrame->hasHostCallFrameFlag())
-        return;
-
-    CodeBlock* callerCodeBlock = callerFrame->codeBlock();
-    if (!callerCodeBlock)
-        return;
-
-    unsigned bytecodeOffset = bytecodeOffsetForPC(callerFrame, callerCodeBlock, callFrame->returnPC());
-    lineNumber = callerCodeBlock->lineNumberForBytecodeOffset(callerFrame, bytecodeOffset - 1);
-    sourceID = callerCodeBlock->ownerExecutable()->sourceID();
-    sourceURL = callerCodeBlock->ownerExecutable()->sourceURL();
-    function = callerFrame->callee();
-}
-
-CallFrame* Interpreter::findFunctionCallFrame(CallFrame* callFrame, InternalFunction* function)
-{
-    for (CallFrame* candidate = callFrame; candidate; candidate = candidate->callerFrame()->removeHostCallFrameFlag()) {
-        if (candidate->callee() == function)
-            return candidate;
-    }
-    return 0;
-}
+    ASSERT(!callFrame->hadException());
+}    
 
 void Interpreter::enableSampler()
 {
 #if ENABLE(OPCODE_SAMPLING)
     if (!m_sampler) {
-        m_sampler.set(new SamplingTool(this));
+        m_sampler = std::make_unique<SamplingTool>(this);
         m_sampler->setup();
     }
 #endif