JavaScriptCore-1218.34.tar.gz

[apple/javascriptcore.git] / dfg / DFGOperations.cpp

/*
 * Copyright (C) 2011 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
 */

#include "config.h"
#include "DFGOperations.h"

#include "Arguments.h"
#include "ButterflyInlines.h"
#include "CodeBlock.h"
#include "CopiedSpaceInlines.h"
#include "DFGOSRExit.h"
#include "DFGRepatch.h"
#include "DFGThunks.h"
#include "HostCallReturnValue.h"
#include "GetterSetter.h"
#include "Interpreter.h"
#include "JIT.h"
#include "JITExceptions.h"
#include "JSActivation.h"
#include "VM.h"
#include "JSNameScope.h"
#include "NameInstance.h"
#include "ObjectConstructor.h"
#include "Operations.h"
#include "StringConstructor.h"
#include <wtf/InlineASM.h>

#if ENABLE(JIT)

#if CPU(MIPS)
#if WTF_MIPS_PIC
#define LOAD_FUNCTION_TO_T9(function) \
        ".set noreorder" "\n" \
        ".cpload $25" "\n" \
        ".set reorder" "\n" \
        "la $t9, " LOCAL_REFERENCE(function) "\n"
#else
#define LOAD_FUNCTION_TO_T9(function) "" "\n"
#endif
#endif

#if ENABLE(DFG_JIT)

#if COMPILER(GCC) && CPU(X86_64)

#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS(function, register) \
    asm( \
    ".globl " SYMBOL_STRING(function) "\n" \
    HIDE_SYMBOL(function) "\n" \
    SYMBOL_STRING(function) ":" "\n" \
        "mov (%rsp), %" STRINGIZE(register) "\n" \
        "jmp " LOCAL_REFERENCE(function##WithReturnAddress) "\n" \
    );
#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_E(function)    FUNCTION_WRAPPER_WITH_RETURN_ADDRESS(function, rsi)
#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_ECI(function)  FUNCTION_WRAPPER_WITH_RETURN_ADDRESS(function, rcx)
#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJI(function)  FUNCTION_WRAPPER_WITH_RETURN_ADDRESS(function, rcx)
#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJCI(function) FUNCTION_WRAPPER_WITH_RETURN_ADDRESS(function, r8)

#elif COMPILER(GCC) && CPU(X86)

#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS(function, offset) \
    asm( \
    ".text" "\n" \
    ".globl " SYMBOL_STRING(function) "\n" \
    HIDE_SYMBOL(function) "\n" \
    SYMBOL_STRING(function) ":" "\n" \
        "mov (%esp), %eax\n" \
        "mov %eax, " STRINGIZE(offset) "(%esp)\n" \
        "jmp " LOCAL_REFERENCE(function##WithReturnAddress) "\n" \
    );
#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_E(function)    FUNCTION_WRAPPER_WITH_RETURN_ADDRESS(function, 8)
#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_ECI(function)  FUNCTION_WRAPPER_WITH_RETURN_ADDRESS(function, 16)
#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJI(function)  FUNCTION_WRAPPER_WITH_RETURN_ADDRESS(function, 20)
#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJCI(function) FUNCTION_WRAPPER_WITH_RETURN_ADDRESS(function, 24)

#elif CPU(ARM64)

#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_E(function) \
    asm ( \
    ".text" "\n" \
    ".align 2" "\n" \
    ".globl " SYMBOL_STRING(function) "\n" \
    HIDE_SYMBOL(function) "\n" \
    SYMBOL_STRING(function) ":" "\n" \
        "mov x1, lr" "\n" \
        "b " LOCAL_REFERENCE(function) "WithReturnAddress" "\n" \
    );

#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_ECI(function) \
    asm ( \
    ".text" "\n" \
    ".align 2" "\n" \
    ".globl " SYMBOL_STRING(function) "\n" \
    HIDE_SYMBOL(function) "\n" \
    SYMBOL_STRING(function) ":" "\n" \
        "mov x3, lr" "\n" \
        "b " LOCAL_REFERENCE(function) "WithReturnAddress" "\n" \
    );

#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJI(function) \
    asm ( \
    ".text" "\n" \
    ".align 2" "\n" \
    ".globl " SYMBOL_STRING(function) "\n" \
    HIDE_SYMBOL(function) "\n" \
    SYMBOL_STRING(function) ":" "\n" \
        "mov x3, lr" "\n" \
        "b " LOCAL_REFERENCE(function) "WithReturnAddress" "\n" \
    );

#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJCI(function) \
    asm ( \
    ".text" "\n" \
    ".align 2" "\n" \
    ".globl " SYMBOL_STRING(function) "\n" \
    HIDE_SYMBOL(function) "\n" \
    SYMBOL_STRING(function) ":" "\n" \
        "mov x4, lr" "\n" \
        "b " LOCAL_REFERENCE(function) "WithReturnAddress" "\n" \
    );

#elif COMPILER(GCC) && CPU(ARM_THUMB2)

#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_E(function) \
    asm ( \
    ".text" "\n" \
    ".align 2" "\n" \
    ".globl " SYMBOL_STRING(function) "\n" \
    HIDE_SYMBOL(function) "\n" \
    ".thumb" "\n" \
    ".thumb_func " THUMB_FUNC_PARAM(function) "\n" \
    SYMBOL_STRING(function) ":" "\n" \
        "mov a2, lr" "\n" \
        "b " LOCAL_REFERENCE(function) "WithReturnAddress" "\n" \
    );

#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_ECI(function) \
    asm ( \
    ".text" "\n" \
    ".align 2" "\n" \
    ".globl " SYMBOL_STRING(function) "\n" \
    HIDE_SYMBOL(function) "\n" \
    ".thumb" "\n" \
    ".thumb_func " THUMB_FUNC_PARAM(function) "\n" \
    SYMBOL_STRING(function) ":" "\n" \
        "mov a4, lr" "\n" \
        "b " LOCAL_REFERENCE(function) "WithReturnAddress" "\n" \
    );

// EncodedJSValue in JSVALUE32_64 is a 64-bit integer. When being compiled in ARM EABI, it must be aligned even-numbered register (r0, r2 or [sp]).
// As a result, return address will be at a 4-byte further location in the following cases.
#if COMPILER_SUPPORTS(EABI) && CPU(ARM)
#define INSTRUCTION_STORE_RETURN_ADDRESS_EJI "str lr, [sp, #4]"
#define INSTRUCTION_STORE_RETURN_ADDRESS_EJCI "str lr, [sp, #8]"
#else
#define INSTRUCTION_STORE_RETURN_ADDRESS_EJI "str lr, [sp, #0]"
#define INSTRUCTION_STORE_RETURN_ADDRESS_EJCI "str lr, [sp, #4]"
#endif

#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJI(function) \
    asm ( \
    ".text" "\n" \
    ".align 2" "\n" \
    ".globl " SYMBOL_STRING(function) "\n" \
    HIDE_SYMBOL(function) "\n" \
    ".thumb" "\n" \
    ".thumb_func " THUMB_FUNC_PARAM(function) "\n" \
    SYMBOL_STRING(function) ":" "\n" \
        INSTRUCTION_STORE_RETURN_ADDRESS_EJI "\n" \
        "b " LOCAL_REFERENCE(function) "WithReturnAddress" "\n" \
    );

#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJCI(function) \
    asm ( \
    ".text" "\n" \
    ".align 2" "\n" \
    ".globl " SYMBOL_STRING(function) "\n" \
    HIDE_SYMBOL(function) "\n" \
    ".thumb" "\n" \
    ".thumb_func " THUMB_FUNC_PARAM(function) "\n" \
    SYMBOL_STRING(function) ":" "\n" \
        INSTRUCTION_STORE_RETURN_ADDRESS_EJCI "\n" \
        "b " LOCAL_REFERENCE(function) "WithReturnAddress" "\n" \
    );

#elif COMPILER(GCC) && CPU(ARM_TRADITIONAL)

#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_E(function) \
    asm ( \
    ".text" "\n" \
    ".globl " SYMBOL_STRING(function) "\n" \
    HIDE_SYMBOL(function) "\n" \
    INLINE_ARM_FUNCTION(function) \
    SYMBOL_STRING(function) ":" "\n" \
        "mov a2, lr" "\n" \
        "b " LOCAL_REFERENCE(function) "WithReturnAddress" "\n" \
    );

#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_ECI(function) \
    asm ( \
    ".text" "\n" \
    ".globl " SYMBOL_STRING(function) "\n" \
    HIDE_SYMBOL(function) "\n" \
    INLINE_ARM_FUNCTION(function) \
    SYMBOL_STRING(function) ":" "\n" \
        "mov a4, lr" "\n" \
        "b " LOCAL_REFERENCE(function) "WithReturnAddress" "\n" \
    );

// EncodedJSValue in JSVALUE32_64 is a 64-bit integer. When being compiled in ARM EABI, it must be aligned even-numbered register (r0, r2 or [sp]).
// As a result, return address will be at a 4-byte further location in the following cases.
#if COMPILER_SUPPORTS(EABI) && CPU(ARM)
#define INSTRUCTION_STORE_RETURN_ADDRESS_EJI "str lr, [sp, #4]"
#define INSTRUCTION_STORE_RETURN_ADDRESS_EJCI "str lr, [sp, #8]"
#else
#define INSTRUCTION_STORE_RETURN_ADDRESS_EJI "str lr, [sp, #0]"
#define INSTRUCTION_STORE_RETURN_ADDRESS_EJCI "str lr, [sp, #4]"
#endif

#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJI(function) \
    asm ( \
    ".text" "\n" \
    ".globl " SYMBOL_STRING(function) "\n" \
    HIDE_SYMBOL(function) "\n" \
    INLINE_ARM_FUNCTION(function) \
    SYMBOL_STRING(function) ":" "\n" \
        INSTRUCTION_STORE_RETURN_ADDRESS_EJI "\n" \
        "b " LOCAL_REFERENCE(function) "WithReturnAddress" "\n" \
    );

#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJCI(function) \
    asm ( \
    ".text" "\n" \
    ".globl " SYMBOL_STRING(function) "\n" \
    HIDE_SYMBOL(function) "\n" \
    INLINE_ARM_FUNCTION(function) \
    SYMBOL_STRING(function) ":" "\n" \
        INSTRUCTION_STORE_RETURN_ADDRESS_EJCI "\n" \
        "b " LOCAL_REFERENCE(function) "WithReturnAddress" "\n" \
    );

#elif COMPILER(GCC) && CPU(MIPS)

#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_E(function) \
    asm( \
    ".text" "\n" \
    ".globl " SYMBOL_STRING(function) "\n" \
    HIDE_SYMBOL(function) "\n" \
    SYMBOL_STRING(function) ":" "\n" \
    LOAD_FUNCTION_TO_T9(function##WithReturnAddress) \
        "move $a1, $ra" "\n" \
        "b " LOCAL_REFERENCE(function) "WithReturnAddress" "\n" \
    );

#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_ECI(function) \
    asm( \
    ".text" "\n" \
    ".globl " SYMBOL_STRING(function) "\n" \
    HIDE_SYMBOL(function) "\n" \
    SYMBOL_STRING(function) ":" "\n" \
    LOAD_FUNCTION_TO_T9(function##WithReturnAddress) \
        "move $a3, $ra" "\n" \
        "b " LOCAL_REFERENCE(function) "WithReturnAddress" "\n" \
    );

#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJI(function) \
    asm( \
    ".text" "\n" \
    ".globl " SYMBOL_STRING(function) "\n" \
    HIDE_SYMBOL(function) "\n" \
    SYMBOL_STRING(function) ":" "\n" \
    LOAD_FUNCTION_TO_T9(function##WithReturnAddress) \
        "sw $ra, 20($sp)" "\n" \
        "b " LOCAL_REFERENCE(function) "WithReturnAddress" "\n" \
    );

#define FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJCI(function) \
    asm( \
    ".text" "\n" \
    ".globl " SYMBOL_STRING(function) "\n" \
    HIDE_SYMBOL(function) "\n" \
    SYMBOL_STRING(function) ":" "\n" \
    LOAD_FUNCTION_TO_T9(function##WithReturnAddress) \
        "sw $ra, 24($sp)" "\n" \
        "b " LOCAL_REFERENCE(function) "WithReturnAddress" "\n" \
    );

#endif

#define P_FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_E(function) \
void* DFG_OPERATION function##WithReturnAddress(ExecState*, ReturnAddressPtr) REFERENCED_FROM_ASM WTF_INTERNAL; \
FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_E(function)

#define J_FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_ECI(function) \
EncodedJSValue DFG_OPERATION function##WithReturnAddress(ExecState*, JSCell*, Identifier*, ReturnAddressPtr) REFERENCED_FROM_ASM WTF_INTERNAL; \
FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_ECI(function)

#define J_FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJI(function) \
EncodedJSValue DFG_OPERATION function##WithReturnAddress(ExecState*, EncodedJSValue, Identifier*, ReturnAddressPtr) REFERENCED_FROM_ASM WTF_INTERNAL; \
FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJI(function)

#define V_FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJCI(function) \
void DFG_OPERATION function##WithReturnAddress(ExecState*, EncodedJSValue, JSCell*, Identifier*, ReturnAddressPtr) REFERENCED_FROM_ASM WTF_INTERNAL; \
FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJCI(function)

namespace JSC { namespace DFG {

template<bool strict>
static inline void putByVal(ExecState* exec, JSValue baseValue, uint32_t index, JSValue value)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    
    if (baseValue.isObject()) {
        JSObject* object = asObject(baseValue);
        if (object->canSetIndexQuickly(index)) {
            object->setIndexQuickly(vm, index, value);
            return;
        }

        object->methodTable()->putByIndex(object, exec, index, value, strict);
        return;
    }

    baseValue.putByIndex(exec, index, value, strict);
}

template<bool strict>
ALWAYS_INLINE static void DFG_OPERATION operationPutByValInternal(ExecState* exec, EncodedJSValue encodedBase, EncodedJSValue encodedProperty, EncodedJSValue encodedValue)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);

    JSValue baseValue = JSValue::decode(encodedBase);
    JSValue property = JSValue::decode(encodedProperty);
    JSValue value = JSValue::decode(encodedValue);

    if (LIKELY(property.isUInt32())) {
        putByVal<strict>(exec, baseValue, property.asUInt32(), value);
        return;
    }

    if (property.isDouble()) {
        double propertyAsDouble = property.asDouble();
        uint32_t propertyAsUInt32 = static_cast<uint32_t>(propertyAsDouble);
        if (propertyAsDouble == propertyAsUInt32) {
            putByVal<strict>(exec, baseValue, propertyAsUInt32, value);
            return;
        }
    }

    if (isName(property)) {
        PutPropertySlot slot(strict);
        baseValue.put(exec, jsCast<NameInstance*>(property.asCell())->privateName(), value, slot);
        return;
    }

    // Don't put to an object if toString throws an exception.
    Identifier ident(exec, property.toString(exec)->value(exec));
    if (!vm->exception) {
        PutPropertySlot slot(strict);
        baseValue.put(exec, ident, value, slot);
    }
}

extern "C" {

EncodedJSValue DFG_OPERATION operationConvertThis(ExecState* exec, EncodedJSValue encodedOp)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);

    return JSValue::encode(JSValue::decode(encodedOp).toThisObject(exec));
}

JSCell* DFG_OPERATION operationCreateThis(ExecState* exec, JSObject* constructor, int32_t inlineCapacity)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);

#if !ASSERT_DISABLED
    ConstructData constructData;
    ASSERT(jsCast<JSFunction*>(constructor)->methodTable()->getConstructData(jsCast<JSFunction*>(constructor), constructData) == ConstructTypeJS);
#endif
    
    return constructEmptyObject(exec, jsCast<JSFunction*>(constructor)->allocationProfile(exec, inlineCapacity)->structure());
}

JSCell* DFG_OPERATION operationNewObject(ExecState* exec, Structure* structure)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    return constructEmptyObject(exec, structure);
}

EncodedJSValue DFG_OPERATION operationValueAdd(ExecState* exec, EncodedJSValue encodedOp1, EncodedJSValue encodedOp2)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    JSValue op1 = JSValue::decode(encodedOp1);
    JSValue op2 = JSValue::decode(encodedOp2);
    
    return JSValue::encode(jsAdd(exec, op1, op2));
}

EncodedJSValue DFG_OPERATION operationValueAddNotNumber(ExecState* exec, EncodedJSValue encodedOp1, EncodedJSValue encodedOp2)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    JSValue op1 = JSValue::decode(encodedOp1);
    JSValue op2 = JSValue::decode(encodedOp2);
    
    ASSERT(!op1.isNumber() || !op2.isNumber());
    
    if (op1.isString() && !op2.isObject())
        return JSValue::encode(jsString(exec, asString(op1), op2.toString(exec)));

    return JSValue::encode(jsAddSlowCase(exec, op1, op2));
}

static inline EncodedJSValue getByVal(ExecState* exec, JSCell* base, uint32_t index)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    
    if (base->isObject()) {
        JSObject* object = asObject(base);
        if (object->canGetIndexQuickly(index))
            return JSValue::encode(object->getIndexQuickly(index));
    }

    if (isJSString(base) && asString(base)->canGetIndex(index))
        return JSValue::encode(asString(base)->getIndex(exec, index));

    return JSValue::encode(JSValue(base).get(exec, index));
}

EncodedJSValue DFG_OPERATION operationGetByVal(ExecState* exec, EncodedJSValue encodedBase, EncodedJSValue encodedProperty)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    JSValue baseValue = JSValue::decode(encodedBase);
    JSValue property = JSValue::decode(encodedProperty);

    if (LIKELY(baseValue.isCell())) {
        JSCell* base = baseValue.asCell();

        if (property.isUInt32()) {
            return getByVal(exec, base, property.asUInt32());
        } else if (property.isDouble()) {
            double propertyAsDouble = property.asDouble();
            uint32_t propertyAsUInt32 = static_cast<uint32_t>(propertyAsDouble);
            if (propertyAsUInt32 == propertyAsDouble)
                return getByVal(exec, base, propertyAsUInt32);
        } else if (property.isString()) {
            if (JSValue result = base->fastGetOwnProperty(exec, asString(property)->value(exec)))
                return JSValue::encode(result);
        }
    }

    if (isName(property))
        return JSValue::encode(baseValue.get(exec, jsCast<NameInstance*>(property.asCell())->privateName()));

    Identifier ident(exec, property.toString(exec)->value(exec));
    return JSValue::encode(baseValue.get(exec, ident));
}

EncodedJSValue DFG_OPERATION operationGetByValCell(ExecState* exec, JSCell* base, EncodedJSValue encodedProperty)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    JSValue property = JSValue::decode(encodedProperty);

    if (property.isUInt32())
        return getByVal(exec, base, property.asUInt32());
    if (property.isDouble()) {
        double propertyAsDouble = property.asDouble();
        uint32_t propertyAsUInt32 = static_cast<uint32_t>(propertyAsDouble);
        if (propertyAsUInt32 == propertyAsDouble)
            return getByVal(exec, base, propertyAsUInt32);
    } else if (property.isString()) {
        if (JSValue result = base->fastGetOwnProperty(exec, asString(property)->value(exec)))
            return JSValue::encode(result);
    }

    if (isName(property))
        return JSValue::encode(JSValue(base).get(exec, jsCast<NameInstance*>(property.asCell())->privateName()));

    Identifier ident(exec, property.toString(exec)->value(exec));
    return JSValue::encode(JSValue(base).get(exec, ident));
}

EncodedJSValue DFG_OPERATION operationGetByValArrayInt(ExecState* exec, JSArray* base, int32_t index)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    if (index < 0) {
        // Go the slowest way possible becase negative indices don't use indexed storage.
        return JSValue::encode(JSValue(base).get(exec, Identifier::from(exec, index)));
    }

    // Use this since we know that the value is out of bounds.
    return JSValue::encode(JSValue(base).get(exec, index));
}

EncodedJSValue DFG_OPERATION operationGetById(ExecState* exec, EncodedJSValue base, Identifier* propertyName)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    JSValue baseValue = JSValue::decode(base);
    PropertySlot slot(baseValue);
    return JSValue::encode(baseValue.get(exec, *propertyName, slot));
}

J_FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJI(operationGetByIdBuildList);
EncodedJSValue DFG_OPERATION operationGetByIdBuildListWithReturnAddress(ExecState* exec, EncodedJSValue base, Identifier* propertyName, ReturnAddressPtr returnAddress)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    StructureStubInfo& stubInfo = exec->codeBlock()->getStubInfo(returnAddress);
    AccessType accessType = static_cast<AccessType>(stubInfo.accessType);

    JSValue baseValue = JSValue::decode(base);
    PropertySlot slot(baseValue);
    JSValue result = baseValue.get(exec, *propertyName, slot);

    if (accessType == static_cast<AccessType>(stubInfo.accessType))
        dfgBuildGetByIDList(exec, baseValue, *propertyName, slot, stubInfo);

    return JSValue::encode(result);
}

J_FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJI(operationGetByIdProtoBuildList);
EncodedJSValue DFG_OPERATION operationGetByIdProtoBuildListWithReturnAddress(ExecState* exec, EncodedJSValue base, Identifier* propertyName, ReturnAddressPtr returnAddress)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    StructureStubInfo& stubInfo = exec->codeBlock()->getStubInfo(returnAddress);
    AccessType accessType = static_cast<AccessType>(stubInfo.accessType);

    JSValue baseValue = JSValue::decode(base);
    PropertySlot slot(baseValue);
    JSValue result = baseValue.get(exec, *propertyName, slot);
    
    if (accessType == static_cast<AccessType>(stubInfo.accessType))
        dfgBuildGetByIDProtoList(exec, baseValue, *propertyName, slot, stubInfo);

    return JSValue::encode(result);
}

J_FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJI(operationGetByIdOptimize);
EncodedJSValue DFG_OPERATION operationGetByIdOptimizeWithReturnAddress(ExecState* exec, EncodedJSValue base, Identifier* propertyName, ReturnAddressPtr returnAddress)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    StructureStubInfo& stubInfo = exec->codeBlock()->getStubInfo(returnAddress);
    AccessType accessType = static_cast<AccessType>(stubInfo.accessType);

    JSValue baseValue = JSValue::decode(base);
    PropertySlot slot(baseValue);
    JSValue result = baseValue.get(exec, *propertyName, slot);
    
    if (accessType == static_cast<AccessType>(stubInfo.accessType)) {
        if (stubInfo.seen)
            dfgRepatchGetByID(exec, baseValue, *propertyName, slot, stubInfo);
        else
            stubInfo.seen = true;
    }

    return JSValue::encode(result);
}

EncodedJSValue DFG_OPERATION operationCallCustomGetter(ExecState* exec, JSCell* base, PropertySlot::GetValueFunc function, Identifier* ident)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    return JSValue::encode(function(exec, asObject(base), *ident));
}

EncodedJSValue DFG_OPERATION operationCallGetter(ExecState* exec, JSCell* base, JSCell* value)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    GetterSetter* getterSetter = asGetterSetter(value);
    JSObject* getter = getterSetter->getter();
    if (!getter)
        return JSValue::encode(jsUndefined());
    CallData callData;
    CallType callType = getter->methodTable()->getCallData(getter, callData);
    return JSValue::encode(call(exec, getter, callType, callData, asObject(base), ArgList()));
}

void DFG_OPERATION operationPutByValStrict(ExecState* exec, EncodedJSValue encodedBase, EncodedJSValue encodedProperty, EncodedJSValue encodedValue)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    operationPutByValInternal<true>(exec, encodedBase, encodedProperty, encodedValue);
}

void DFG_OPERATION operationPutByValNonStrict(ExecState* exec, EncodedJSValue encodedBase, EncodedJSValue encodedProperty, EncodedJSValue encodedValue)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    operationPutByValInternal<false>(exec, encodedBase, encodedProperty, encodedValue);
}

void DFG_OPERATION operationPutByValCellStrict(ExecState* exec, JSCell* cell, EncodedJSValue encodedProperty, EncodedJSValue encodedValue)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    operationPutByValInternal<true>(exec, JSValue::encode(cell), encodedProperty, encodedValue);
}

void DFG_OPERATION operationPutByValCellNonStrict(ExecState* exec, JSCell* cell, EncodedJSValue encodedProperty, EncodedJSValue encodedValue)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    operationPutByValInternal<false>(exec, JSValue::encode(cell), encodedProperty, encodedValue);
}

void DFG_OPERATION operationPutByValBeyondArrayBoundsStrict(ExecState* exec, JSObject* array, int32_t index, EncodedJSValue encodedValue)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    if (index >= 0) {
        array->putByIndexInline(exec, index, JSValue::decode(encodedValue), true);
        return;
    }
    
    PutPropertySlot slot(true);
    array->methodTable()->put(
        array, exec, Identifier::from(exec, index), JSValue::decode(encodedValue), slot);
}

void DFG_OPERATION operationPutByValBeyondArrayBoundsNonStrict(ExecState* exec, JSObject* array, int32_t index, EncodedJSValue encodedValue)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    if (index >= 0) {
        array->putByIndexInline(exec, index, JSValue::decode(encodedValue), false);
        return;
    }
    
    PutPropertySlot slot(false);
    array->methodTable()->put(
        array, exec, Identifier::from(exec, index), JSValue::decode(encodedValue), slot);
}

void DFG_OPERATION operationPutDoubleByValBeyondArrayBoundsStrict(ExecState* exec, JSObject* array, int32_t index, double value)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    JSValue jsValue = JSValue(JSValue::EncodeAsDouble, value);
    
    if (index >= 0) {
        array->putByIndexInline(exec, index, jsValue, true);
        return;
    }
    
    PutPropertySlot slot(true);
    array->methodTable()->put(
        array, exec, Identifier::from(exec, index), jsValue, slot);
}

void DFG_OPERATION operationPutDoubleByValBeyondArrayBoundsNonStrict(ExecState* exec, JSObject* array, int32_t index, double value)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    JSValue jsValue = JSValue(JSValue::EncodeAsDouble, value);
    
    if (index >= 0) {
        array->putByIndexInline(exec, index, jsValue, false);
        return;
    }
    
    PutPropertySlot slot(false);
    array->methodTable()->put(
        array, exec, Identifier::from(exec, index), jsValue, slot);
}

EncodedJSValue DFG_OPERATION operationArrayPush(ExecState* exec, EncodedJSValue encodedValue, JSArray* array)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    array->push(exec, JSValue::decode(encodedValue));
    return JSValue::encode(jsNumber(array->length()));
}

EncodedJSValue DFG_OPERATION operationArrayPushDouble(ExecState* exec, double value, JSArray* array)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    array->push(exec, JSValue(JSValue::EncodeAsDouble, value));
    return JSValue::encode(jsNumber(array->length()));
}

EncodedJSValue DFG_OPERATION operationArrayPop(ExecState* exec, JSArray* array)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    return JSValue::encode(array->pop(exec));
}
        
EncodedJSValue DFG_OPERATION operationArrayPopAndRecoverLength(ExecState* exec, JSArray* array)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    array->butterfly()->setPublicLength(array->butterfly()->publicLength() + 1);
    
    return JSValue::encode(array->pop(exec));
}
        
EncodedJSValue DFG_OPERATION operationRegExpExec(ExecState* exec, JSCell* base, JSCell* argument)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    
    if (!base->inherits(&RegExpObject::s_info))
        return throwVMTypeError(exec);

    ASSERT(argument->isString() || argument->isObject());
    JSString* input = argument->isString() ? asString(argument) : asObject(argument)->toString(exec);
    return JSValue::encode(asRegExpObject(base)->exec(exec, input));
}
        
size_t DFG_OPERATION operationRegExpTest(ExecState* exec, JSCell* base, JSCell* argument)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);

    if (!base->inherits(&RegExpObject::s_info)) {
        throwTypeError(exec);
        return false;
    }

    ASSERT(argument->isString() || argument->isObject());
    JSString* input = argument->isString() ? asString(argument) : asObject(argument)->toString(exec);
    return asRegExpObject(base)->test(exec, input);
}
        
void DFG_OPERATION operationPutByIdStrict(ExecState* exec, EncodedJSValue encodedValue, JSCell* base, Identifier* propertyName)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    PutPropertySlot slot(true);
    base->methodTable()->put(base, exec, *propertyName, JSValue::decode(encodedValue), slot);
}

void DFG_OPERATION operationPutByIdNonStrict(ExecState* exec, EncodedJSValue encodedValue, JSCell* base, Identifier* propertyName)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    PutPropertySlot slot(false);
    base->methodTable()->put(base, exec, *propertyName, JSValue::decode(encodedValue), slot);
}

void DFG_OPERATION operationPutByIdDirectStrict(ExecState* exec, EncodedJSValue encodedValue, JSCell* base, Identifier* propertyName)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    PutPropertySlot slot(true);
    ASSERT(base->isObject());
    asObject(base)->putDirect(exec->vm(), *propertyName, JSValue::decode(encodedValue), slot);
}

void DFG_OPERATION operationPutByIdDirectNonStrict(ExecState* exec, EncodedJSValue encodedValue, JSCell* base, Identifier* propertyName)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    PutPropertySlot slot(false);
    ASSERT(base->isObject());
    asObject(base)->putDirect(exec->vm(), *propertyName, JSValue::decode(encodedValue), slot);
}

V_FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJCI(operationPutByIdStrictOptimize);
void DFG_OPERATION operationPutByIdStrictOptimizeWithReturnAddress(ExecState* exec, EncodedJSValue encodedValue, JSCell* base, Identifier* propertyName, ReturnAddressPtr returnAddress)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    StructureStubInfo& stubInfo = exec->codeBlock()->getStubInfo(returnAddress);
    AccessType accessType = static_cast<AccessType>(stubInfo.accessType);

    JSValue value = JSValue::decode(encodedValue);
    JSValue baseValue(base);
    PutPropertySlot slot(true);
    
    baseValue.put(exec, *propertyName, value, slot);
    
    if (accessType != static_cast<AccessType>(stubInfo.accessType))
        return;
    
    if (stubInfo.seen)
        dfgRepatchPutByID(exec, baseValue, *propertyName, slot, stubInfo, NotDirect);
    else
        stubInfo.seen = true;
}

V_FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJCI(operationPutByIdNonStrictOptimize);
void DFG_OPERATION operationPutByIdNonStrictOptimizeWithReturnAddress(ExecState* exec, EncodedJSValue encodedValue, JSCell* base, Identifier* propertyName, ReturnAddressPtr returnAddress)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    StructureStubInfo& stubInfo = exec->codeBlock()->getStubInfo(returnAddress);
    AccessType accessType = static_cast<AccessType>(stubInfo.accessType);

    JSValue value = JSValue::decode(encodedValue);
    JSValue baseValue(base);
    PutPropertySlot slot(false);
    
    baseValue.put(exec, *propertyName, value, slot);
    
    if (accessType != static_cast<AccessType>(stubInfo.accessType))
        return;
    
    if (stubInfo.seen)
        dfgRepatchPutByID(exec, baseValue, *propertyName, slot, stubInfo, NotDirect);
    else
        stubInfo.seen = true;
}

V_FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJCI(operationPutByIdDirectStrictOptimize);
void DFG_OPERATION operationPutByIdDirectStrictOptimizeWithReturnAddress(ExecState* exec, EncodedJSValue encodedValue, JSCell* base, Identifier* propertyName, ReturnAddressPtr returnAddress)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    StructureStubInfo& stubInfo = exec->codeBlock()->getStubInfo(returnAddress);
    AccessType accessType = static_cast<AccessType>(stubInfo.accessType);

    JSValue value = JSValue::decode(encodedValue);
    PutPropertySlot slot(true);
    
    ASSERT(base->isObject());
    asObject(base)->putDirect(exec->vm(), *propertyName, value, slot);
    
    if (accessType != static_cast<AccessType>(stubInfo.accessType))
        return;
    
    if (stubInfo.seen)
        dfgRepatchPutByID(exec, base, *propertyName, slot, stubInfo, Direct);
    else
        stubInfo.seen = true;
}

V_FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJCI(operationPutByIdDirectNonStrictOptimize);
void DFG_OPERATION operationPutByIdDirectNonStrictOptimizeWithReturnAddress(ExecState* exec, EncodedJSValue encodedValue, JSCell* base, Identifier* propertyName, ReturnAddressPtr returnAddress)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    StructureStubInfo& stubInfo = exec->codeBlock()->getStubInfo(returnAddress);
    AccessType accessType = static_cast<AccessType>(stubInfo.accessType);

    JSValue value = JSValue::decode(encodedValue);
    PutPropertySlot slot(false);
    
    ASSERT(base->isObject());
    asObject(base)->putDirect(exec->vm(), *propertyName, value, slot);
    
    if (accessType != static_cast<AccessType>(stubInfo.accessType))
        return;
    
    if (stubInfo.seen)
        dfgRepatchPutByID(exec, base, *propertyName, slot, stubInfo, Direct);
    else
        stubInfo.seen = true;
}

V_FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJCI(operationPutByIdStrictBuildList);
void DFG_OPERATION operationPutByIdStrictBuildListWithReturnAddress(ExecState* exec, EncodedJSValue encodedValue, JSCell* base, Identifier* propertyName, ReturnAddressPtr returnAddress)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    StructureStubInfo& stubInfo = exec->codeBlock()->getStubInfo(returnAddress);
    AccessType accessType = static_cast<AccessType>(stubInfo.accessType);

    JSValue value = JSValue::decode(encodedValue);
    JSValue baseValue(base);
    PutPropertySlot slot(true);
    
    baseValue.put(exec, *propertyName, value, slot);
    
    if (accessType != static_cast<AccessType>(stubInfo.accessType))
        return;
    
    dfgBuildPutByIdList(exec, baseValue, *propertyName, slot, stubInfo, NotDirect);
}

V_FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJCI(operationPutByIdNonStrictBuildList);
void DFG_OPERATION operationPutByIdNonStrictBuildListWithReturnAddress(ExecState* exec, EncodedJSValue encodedValue, JSCell* base, Identifier* propertyName, ReturnAddressPtr returnAddress)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    StructureStubInfo& stubInfo = exec->codeBlock()->getStubInfo(returnAddress);
    AccessType accessType = static_cast<AccessType>(stubInfo.accessType);

    JSValue value = JSValue::decode(encodedValue);
    JSValue baseValue(base);
    PutPropertySlot slot(false);
    
    baseValue.put(exec, *propertyName, value, slot);
    
    if (accessType != static_cast<AccessType>(stubInfo.accessType))
        return;
    
    dfgBuildPutByIdList(exec, baseValue, *propertyName, slot, stubInfo, NotDirect);
}

V_FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJCI(operationPutByIdDirectStrictBuildList);
void DFG_OPERATION operationPutByIdDirectStrictBuildListWithReturnAddress(ExecState* exec, EncodedJSValue encodedValue, JSCell* base, Identifier* propertyName, ReturnAddressPtr returnAddress)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    StructureStubInfo& stubInfo = exec->codeBlock()->getStubInfo(returnAddress);
    AccessType accessType = static_cast<AccessType>(stubInfo.accessType);
    
    JSValue value = JSValue::decode(encodedValue);
    PutPropertySlot slot(true);
    
    ASSERT(base->isObject());
    asObject(base)->putDirect(exec->vm(), *propertyName, value, slot);
    
    if (accessType != static_cast<AccessType>(stubInfo.accessType))
        return;
    
    dfgBuildPutByIdList(exec, base, *propertyName, slot, stubInfo, Direct);
}

V_FUNCTION_WRAPPER_WITH_RETURN_ADDRESS_EJCI(operationPutByIdDirectNonStrictBuildList);
void DFG_OPERATION operationPutByIdDirectNonStrictBuildListWithReturnAddress(ExecState* exec, EncodedJSValue encodedValue, JSCell* base, Identifier* propertyName, ReturnAddressPtr returnAddress)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    StructureStubInfo& stubInfo = exec->codeBlock()->getStubInfo(returnAddress);
    AccessType accessType = static_cast<AccessType>(stubInfo.accessType);

    JSValue value = JSValue::decode(encodedValue);
    PutPropertySlot slot(false);
    
    ASSERT(base->isObject());
    asObject(base)->putDirect(exec->vm(), *propertyName, value, slot);
    
    if (accessType != static_cast<AccessType>(stubInfo.accessType))
        return;
    
    dfgBuildPutByIdList(exec, base, *propertyName, slot, stubInfo, Direct);
}

size_t DFG_OPERATION operationCompareLess(ExecState* exec, EncodedJSValue encodedOp1, EncodedJSValue encodedOp2)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    return jsLess<true>(exec, JSValue::decode(encodedOp1), JSValue::decode(encodedOp2));
}

size_t DFG_OPERATION operationCompareLessEq(ExecState* exec, EncodedJSValue encodedOp1, EncodedJSValue encodedOp2)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    return jsLessEq<true>(exec, JSValue::decode(encodedOp1), JSValue::decode(encodedOp2));
}

size_t DFG_OPERATION operationCompareGreater(ExecState* exec, EncodedJSValue encodedOp1, EncodedJSValue encodedOp2)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    return jsLess<false>(exec, JSValue::decode(encodedOp2), JSValue::decode(encodedOp1));
}

size_t DFG_OPERATION operationCompareGreaterEq(ExecState* exec, EncodedJSValue encodedOp1, EncodedJSValue encodedOp2)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    return jsLessEq<false>(exec, JSValue::decode(encodedOp2), JSValue::decode(encodedOp1));
}

size_t DFG_OPERATION operationCompareEq(ExecState* exec, EncodedJSValue encodedOp1, EncodedJSValue encodedOp2)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    return JSValue::equalSlowCaseInline(exec, JSValue::decode(encodedOp1), JSValue::decode(encodedOp2));
}

#if USE(JSVALUE64)
EncodedJSValue DFG_OPERATION operationCompareStringEq(ExecState* exec, JSCell* left, JSCell* right)
#else
size_t DFG_OPERATION operationCompareStringEq(ExecState* exec, JSCell* left, JSCell* right)
#endif
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    bool result = asString(left)->value(exec) == asString(right)->value(exec);
#if USE(JSVALUE64)
    return JSValue::encode(jsBoolean(result));
#else
    return result;
#endif
}

size_t DFG_OPERATION operationCompareStrictEqCell(ExecState* exec, EncodedJSValue encodedOp1, EncodedJSValue encodedOp2)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    JSValue op1 = JSValue::decode(encodedOp1);
    JSValue op2 = JSValue::decode(encodedOp2);
    
    ASSERT(op1.isCell());
    ASSERT(op2.isCell());
    
    return JSValue::strictEqualSlowCaseInline(exec, op1, op2);
}

size_t DFG_OPERATION operationCompareStrictEq(ExecState* exec, EncodedJSValue encodedOp1, EncodedJSValue encodedOp2)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);

    JSValue src1 = JSValue::decode(encodedOp1);
    JSValue src2 = JSValue::decode(encodedOp2);
    
    return JSValue::strictEqual(exec, src1, src2);
}

static void* handleHostCall(ExecState* execCallee, JSValue callee, CodeSpecializationKind kind)
{
    ExecState* exec = execCallee->callerFrame();
    VM* vm = &exec->vm();

    execCallee->setScope(exec->scope());
    execCallee->setCodeBlock(0);

    if (kind == CodeForCall) {
        CallData callData;
        CallType callType = getCallData(callee, callData);
    
        ASSERT(callType != CallTypeJS);
    
        if (callType == CallTypeHost) {
            NativeCallFrameTracer tracer(vm, execCallee);
            execCallee->setCallee(asObject(callee));
            vm->hostCallReturnValue = JSValue::decode(callData.native.function(execCallee));
            if (vm->exception)
                return vm->getCTIStub(throwExceptionFromCallSlowPathGenerator).code().executableAddress();

            return reinterpret_cast<void*>(getHostCallReturnValue);
        }
    
        ASSERT(callType == CallTypeNone);
        exec->vm().exception = createNotAFunctionError(exec, callee);
        return vm->getCTIStub(throwExceptionFromCallSlowPathGenerator).code().executableAddress();
    }

    ASSERT(kind == CodeForConstruct);
    
    ConstructData constructData;
    ConstructType constructType = getConstructData(callee, constructData);
    
    ASSERT(constructType != ConstructTypeJS);
    
    if (constructType == ConstructTypeHost) {
        NativeCallFrameTracer tracer(vm, execCallee);
        execCallee->setCallee(asObject(callee));
        vm->hostCallReturnValue = JSValue::decode(constructData.native.function(execCallee));
        if (vm->exception)
            return vm->getCTIStub(throwExceptionFromCallSlowPathGenerator).code().executableAddress();

        return reinterpret_cast<void*>(getHostCallReturnValue);
    }
    
    ASSERT(constructType == ConstructTypeNone);
    exec->vm().exception = createNotAConstructorError(exec, callee);
    return vm->getCTIStub(throwExceptionFromCallSlowPathGenerator).code().executableAddress();
}

inline char* linkFor(ExecState* execCallee, CodeSpecializationKind kind)
{
    ExecState* exec = execCallee->callerFrame();
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    JSValue calleeAsValue = execCallee->calleeAsValue();
    JSCell* calleeAsFunctionCell = getJSFunction(calleeAsValue);
    if (!calleeAsFunctionCell)
        return reinterpret_cast<char*>(handleHostCall(execCallee, calleeAsValue, kind));

    JSFunction* callee = jsCast<JSFunction*>(calleeAsFunctionCell);
    execCallee->setScope(callee->scopeUnchecked());
    ExecutableBase* executable = callee->executable();

    MacroAssemblerCodePtr codePtr;
    CodeBlock* codeBlock = 0;
    if (executable->isHostFunction())
        codePtr = executable->generatedJITCodeFor(kind).addressForCall();
    else {
        FunctionExecutable* functionExecutable = static_cast<FunctionExecutable*>(executable);
        JSObject* error = functionExecutable->compileFor(execCallee, callee->scope(), kind);
        if (error) {
            vm->exception = createStackOverflowError(exec);
            return reinterpret_cast<char*>(vm->getCTIStub(throwExceptionFromCallSlowPathGenerator).code().executableAddress());
        }
        codeBlock = &functionExecutable->generatedBytecodeFor(kind);
        if (execCallee->argumentCountIncludingThis() < static_cast<size_t>(codeBlock->numParameters()))
            codePtr = functionExecutable->generatedJITCodeWithArityCheckFor(kind);
        else
            codePtr = functionExecutable->generatedJITCodeFor(kind).addressForCall();
    }
    CallLinkInfo& callLinkInfo = exec->codeBlock()->getCallLinkInfo(execCallee->returnPC());
    if (!callLinkInfo.seenOnce())
        callLinkInfo.setSeen();
    else
        dfgLinkFor(execCallee, callLinkInfo, codeBlock, callee, codePtr, kind);
    return reinterpret_cast<char*>(codePtr.executableAddress());
}

char* DFG_OPERATION operationLinkCall(ExecState* execCallee)
{
    return linkFor(execCallee, CodeForCall);
}

char* DFG_OPERATION operationLinkConstruct(ExecState* execCallee)
{
    return linkFor(execCallee, CodeForConstruct);
}

inline char* virtualForWithFunction(ExecState* execCallee, CodeSpecializationKind kind, JSCell*& calleeAsFunctionCell)
{
    ExecState* exec = execCallee->callerFrame();
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);

    JSValue calleeAsValue = execCallee->calleeAsValue();
    calleeAsFunctionCell = getJSFunction(calleeAsValue);
    if (UNLIKELY(!calleeAsFunctionCell))
        return reinterpret_cast<char*>(handleHostCall(execCallee, calleeAsValue, kind));
    
    JSFunction* function = jsCast<JSFunction*>(calleeAsFunctionCell);
    execCallee->setScope(function->scopeUnchecked());
    ExecutableBase* executable = function->executable();
    if (UNLIKELY(!executable->hasJITCodeFor(kind))) {
        FunctionExecutable* functionExecutable = static_cast<FunctionExecutable*>(executable);
        JSObject* error = functionExecutable->compileFor(execCallee, function->scope(), kind);
        if (error) {
            exec->vm().exception = error;
            return reinterpret_cast<char*>(vm->getCTIStub(throwExceptionFromCallSlowPathGenerator).code().executableAddress());
        }
    }
    return reinterpret_cast<char*>(executable->generatedJITCodeWithArityCheckFor(kind).executableAddress());
}

inline char* virtualFor(ExecState* execCallee, CodeSpecializationKind kind)
{
    JSCell* calleeAsFunctionCellIgnored;
    return virtualForWithFunction(execCallee, kind, calleeAsFunctionCellIgnored);
}

static bool attemptToOptimizeClosureCall(ExecState* execCallee, JSCell* calleeAsFunctionCell, CallLinkInfo& callLinkInfo)
{
    if (!calleeAsFunctionCell)
        return false;
    
    JSFunction* callee = jsCast<JSFunction*>(calleeAsFunctionCell);
    JSFunction* oldCallee = callLinkInfo.callee.get();
    
    if (!oldCallee
        || oldCallee->structure() != callee->structure()
        || oldCallee->executable() != callee->executable())
        return false;
    
    ASSERT(callee->executable()->hasJITCodeForCall());
    MacroAssemblerCodePtr codePtr = callee->executable()->generatedJITCodeForCall().addressForCall();
    
    CodeBlock* codeBlock;
    if (callee->executable()->isHostFunction())
        codeBlock = 0;
    else {
        codeBlock = &jsCast<FunctionExecutable*>(callee->executable())->generatedBytecodeForCall();
        if (execCallee->argumentCountIncludingThis() < static_cast<size_t>(codeBlock->numParameters()))
            return false;
    }
    
    dfgLinkClosureCall(
        execCallee, callLinkInfo, codeBlock,
        callee->structure(), callee->executable(), codePtr);
    
    return true;
}

char* DFG_OPERATION operationLinkClosureCall(ExecState* execCallee)
{
    JSCell* calleeAsFunctionCell;
    char* result = virtualForWithFunction(execCallee, CodeForCall, calleeAsFunctionCell);
    CallLinkInfo& callLinkInfo = execCallee->callerFrame()->codeBlock()->getCallLinkInfo(execCallee->returnPC());

    if (!attemptToOptimizeClosureCall(execCallee, calleeAsFunctionCell, callLinkInfo))
        dfgLinkSlowFor(execCallee, callLinkInfo, CodeForCall);
    
    return result;
}

char* DFG_OPERATION operationVirtualCall(ExecState* execCallee)
{    
    return virtualFor(execCallee, CodeForCall);
}

char* DFG_OPERATION operationVirtualConstruct(ExecState* execCallee)
{
    return virtualFor(execCallee, CodeForConstruct);
}

void DFG_OPERATION operationNotifyGlobalVarWrite(WatchpointSet* watchpointSet)
{
    watchpointSet->notifyWrite();
}

EncodedJSValue DFG_OPERATION operationResolve(ExecState* exec, Identifier* propertyName, ResolveOperations* operations)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    return JSValue::encode(JSScope::resolve(exec, *propertyName, operations));
}

EncodedJSValue DFG_OPERATION operationResolveBase(ExecState* exec, Identifier* propertyName, ResolveOperations* operations, PutToBaseOperation* putToBaseOperations)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    return JSValue::encode(JSScope::resolveBase(exec, *propertyName, false, operations, putToBaseOperations));
}

EncodedJSValue DFG_OPERATION operationResolveBaseStrictPut(ExecState* exec, Identifier* propertyName, ResolveOperations* operations, PutToBaseOperation* putToBaseOperations)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    return JSValue::encode(JSScope::resolveBase(exec, *propertyName, true, operations, putToBaseOperations));
}

EncodedJSValue DFG_OPERATION operationResolveGlobal(ExecState* exec, ResolveOperation* resolveOperation, JSGlobalObject* globalObject, Identifier* propertyName)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    ASSERT(globalObject);
    UNUSED_PARAM(resolveOperation);
    UNUSED_PARAM(globalObject);
    ASSERT(resolveOperation->m_operation == ResolveOperation::GetAndReturnGlobalProperty);
    return JSValue::encode(JSScope::resolveGlobal(exec, *propertyName, globalObject, resolveOperation));
}

EncodedJSValue DFG_OPERATION operationToPrimitive(ExecState* exec, EncodedJSValue value)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    return JSValue::encode(JSValue::decode(value).toPrimitive(exec));
}

char* DFG_OPERATION operationNewArray(ExecState* exec, Structure* arrayStructure, void* buffer, size_t size)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    return bitwise_cast<char*>(constructArray(exec, arrayStructure, static_cast<JSValue*>(buffer), size));
}

char* DFG_OPERATION operationNewEmptyArray(ExecState* exec, Structure* arrayStructure)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    return bitwise_cast<char*>(JSArray::create(*vm, arrayStructure));
}

char* DFG_OPERATION operationNewArrayWithSize(ExecState* exec, Structure* arrayStructure, int32_t size)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);

    if (UNLIKELY(size < 0))
        return bitwise_cast<char*>(throwError(exec, createRangeError(exec, ASCIILiteral("Array size is not a small enough positive integer."))));

    return bitwise_cast<char*>(JSArray::create(*vm, arrayStructure, size));
}

char* DFG_OPERATION operationNewArrayBuffer(ExecState* exec, Structure* arrayStructure, size_t start, size_t size)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    return bitwise_cast<char*>(constructArray(exec, arrayStructure, exec->codeBlock()->constantBuffer(start), size));
}

EncodedJSValue DFG_OPERATION operationNewRegexp(ExecState* exec, void* regexpPtr)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    RegExp* regexp = static_cast<RegExp*>(regexpPtr);
    if (!regexp->isValid()) {
        throwError(exec, createSyntaxError(exec, "Invalid flags supplied to RegExp constructor."));
        return JSValue::encode(jsUndefined());
    }
    
    return JSValue::encode(RegExpObject::create(exec->vm(), exec->lexicalGlobalObject(), exec->lexicalGlobalObject()->regExpStructure(), regexp));
}

JSCell* DFG_OPERATION operationCreateActivation(ExecState* exec)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    JSActivation* activation = JSActivation::create(vm, exec, exec->codeBlock());
    exec->setScope(activation);
    return activation;
}

JSCell* DFG_OPERATION operationCreateArguments(ExecState* exec)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    // NB: This needs to be exceedingly careful with top call frame tracking, since it
    // may be called from OSR exit, while the state of the call stack is bizarre.
    Arguments* result = Arguments::create(vm, exec);
    ASSERT(!vm.exception);
    return result;
}

JSCell* DFG_OPERATION operationCreateInlinedArguments(
    ExecState* exec, InlineCallFrame* inlineCallFrame)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    // NB: This needs to be exceedingly careful with top call frame tracking, since it
    // may be called from OSR exit, while the state of the call stack is bizarre.
    Arguments* result = Arguments::create(vm, exec, inlineCallFrame);
    ASSERT(!vm.exception);
    return result;
}

void DFG_OPERATION operationTearOffArguments(ExecState* exec, JSCell* argumentsCell, JSCell* activationCell)
{
    ASSERT(exec->codeBlock()->usesArguments());
    if (activationCell) {
        jsCast<Arguments*>(argumentsCell)->didTearOffActivation(exec, jsCast<JSActivation*>(activationCell));
        return;
    }
    jsCast<Arguments*>(argumentsCell)->tearOff(exec);
}

void DFG_OPERATION operationTearOffInlinedArguments(
    ExecState* exec, JSCell* argumentsCell, JSCell* activationCell, InlineCallFrame* inlineCallFrame)
{
    ASSERT_UNUSED(activationCell, !activationCell); // Currently, we don't inline functions with activations.
    jsCast<Arguments*>(argumentsCell)->tearOff(exec, inlineCallFrame);
}

EncodedJSValue DFG_OPERATION operationGetArgumentsLength(ExecState* exec, int32_t argumentsRegister)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    // Here we can assume that the argumernts were created. Because otherwise the JIT code would
    // have not made this call.
    Identifier ident(&vm, "length");
    JSValue baseValue = exec->uncheckedR(argumentsRegister).jsValue();
    PropertySlot slot(baseValue);
    return JSValue::encode(baseValue.get(exec, ident, slot));
}

EncodedJSValue DFG_OPERATION operationGetArgumentByVal(ExecState* exec, int32_t argumentsRegister, int32_t index)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);

    JSValue argumentsValue = exec->uncheckedR(argumentsRegister).jsValue();
    
    // If there are no arguments, and we're accessing out of bounds, then we have to create the
    // arguments in case someone has installed a getter on a numeric property.
    if (!argumentsValue)
        exec->uncheckedR(argumentsRegister) = argumentsValue = Arguments::create(exec->vm(), exec);
    
    return JSValue::encode(argumentsValue.get(exec, index));
}

EncodedJSValue DFG_OPERATION operationGetInlinedArgumentByVal(
    ExecState* exec, int32_t argumentsRegister, InlineCallFrame* inlineCallFrame, int32_t index)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);

    JSValue argumentsValue = exec->uncheckedR(argumentsRegister).jsValue();
    
    // If there are no arguments, and we're accessing out of bounds, then we have to create the
    // arguments in case someone has installed a getter on a numeric property.
    if (!argumentsValue) {
        exec->uncheckedR(argumentsRegister) = argumentsValue =
            Arguments::create(exec->vm(), exec, inlineCallFrame);
    }
    
    return JSValue::encode(argumentsValue.get(exec, index));
}

JSCell* DFG_OPERATION operationNewFunctionNoCheck(ExecState* exec, JSCell* functionExecutable)
{
    ASSERT(functionExecutable->inherits(&FunctionExecutable::s_info));
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    return JSFunction::create(exec, static_cast<FunctionExecutable*>(functionExecutable), exec->scope());
}

EncodedJSValue DFG_OPERATION operationNewFunction(ExecState* exec, JSCell* functionExecutable)
{
    ASSERT(functionExecutable->inherits(&FunctionExecutable::s_info));
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    return JSValue::encode(JSFunction::create(exec, static_cast<FunctionExecutable*>(functionExecutable), exec->scope()));
}

JSCell* DFG_OPERATION operationNewFunctionExpression(ExecState* exec, JSCell* functionExecutableAsCell)
{
    ASSERT(functionExecutableAsCell->inherits(&FunctionExecutable::s_info));

    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);

    FunctionExecutable* functionExecutable =
        static_cast<FunctionExecutable*>(functionExecutableAsCell);
    return JSFunction::create(exec, functionExecutable, exec->scope());
}

size_t DFG_OPERATION operationIsObject(ExecState* exec, EncodedJSValue value)
{
    return jsIsObjectType(exec, JSValue::decode(value));
}

size_t DFG_OPERATION operationIsFunction(EncodedJSValue value)
{
    return jsIsFunctionType(JSValue::decode(value));
}

JSCell* DFG_OPERATION operationTypeOf(ExecState* exec, JSCell* value)
{
    return jsTypeStringForValue(exec, JSValue(value)).asCell();
}

void DFG_OPERATION operationReallocateStorageAndFinishPut(ExecState* exec, JSObject* base, Structure* structure, PropertyOffset offset, EncodedJSValue value)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);

    ASSERT(structure->outOfLineCapacity() > base->structure()->outOfLineCapacity());
    ASSERT(!vm.heap.storageAllocator().fastPathShouldSucceed(structure->outOfLineCapacity() * sizeof(JSValue)));
    base->setStructureAndReallocateStorageIfNecessary(vm, structure);
    base->putDirect(vm, offset, JSValue::decode(value));
}

char* DFG_OPERATION operationAllocatePropertyStorageWithInitialCapacity(ExecState* exec)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);

    return reinterpret_cast<char*>(
        Butterfly::createUninitialized(vm, 0, initialOutOfLineCapacity, false, 0));
}

char* DFG_OPERATION operationAllocatePropertyStorage(ExecState* exec, size_t newSize)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);

    return reinterpret_cast<char*>(
        Butterfly::createUninitialized(vm, 0, newSize, false, 0));
}

char* DFG_OPERATION operationReallocateButterflyToHavePropertyStorageWithInitialCapacity(ExecState* exec, JSObject* object)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);

    ASSERT(!object->structure()->outOfLineCapacity());
    Butterfly* result = object->growOutOfLineStorage(vm, 0, initialOutOfLineCapacity);
    object->setButterflyWithoutChangingStructure(result);
    return reinterpret_cast<char*>(result);
}

char* DFG_OPERATION operationReallocateButterflyToGrowPropertyStorage(ExecState* exec, JSObject* object, size_t newSize)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);

    Butterfly* result = object->growOutOfLineStorage(vm, object->structure()->outOfLineCapacity(), newSize);
    object->setButterflyWithoutChangingStructure(result);
    return reinterpret_cast<char*>(result);
}

char* DFG_OPERATION operationEnsureInt32(ExecState* exec, JSCell* cell)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    
    if (!cell->isObject())
        return 0;
    
    return reinterpret_cast<char*>(asObject(cell)->ensureInt32(vm).data());
}

char* DFG_OPERATION operationEnsureDouble(ExecState* exec, JSCell* cell)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    
    if (!cell->isObject())
        return 0;
    
    return reinterpret_cast<char*>(asObject(cell)->ensureDouble(vm).data());
}

char* DFG_OPERATION operationEnsureContiguous(ExecState* exec, JSCell* cell)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    
    if (!cell->isObject())
        return 0;
    
    return reinterpret_cast<char*>(asObject(cell)->ensureContiguous(vm).data());
}

char* DFG_OPERATION operationRageEnsureContiguous(ExecState* exec, JSCell* cell)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    
    if (!cell->isObject())
        return 0;
    
    return reinterpret_cast<char*>(asObject(cell)->rageEnsureContiguous(vm).data());
}

char* DFG_OPERATION operationEnsureArrayStorage(ExecState* exec, JSCell* cell)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    
    if (!cell->isObject())
        return 0;

    return reinterpret_cast<char*>(asObject(cell)->ensureArrayStorage(vm));
}

StringImpl* DFG_OPERATION operationResolveRope(ExecState* exec, JSString* string)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);

    return string->value(exec).impl();
}

JSCell* DFG_OPERATION operationNewStringObject(ExecState* exec, JSString* string, Structure* structure)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    
    return StringObject::create(exec, structure, string);
}

JSCell* DFG_OPERATION operationToStringOnCell(ExecState* exec, JSCell* cell)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    
    return JSValue(cell).toString(exec);
}

JSCell* DFG_OPERATION operationToString(ExecState* exec, EncodedJSValue value)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);

    return JSValue::decode(value).toString(exec);
}

JSCell* DFG_OPERATION operationMakeRope2(ExecState* exec, JSString* left, JSString* right)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);

    return JSRopeString::create(vm, left, right);
}

JSCell* DFG_OPERATION operationMakeRope3(ExecState* exec, JSString* a, JSString* b, JSString* c)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);

    return JSRopeString::create(vm, a, b, c);
}

double DFG_OPERATION operationFModOnInts(int32_t a, int32_t b)
{
    return fmod(a, b);
}

JSCell* DFG_OPERATION operationStringFromCharCode(ExecState* exec, int32_t op1)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    return JSC::stringFromCharCode(exec, op1);
}

DFGHandlerEncoded DFG_OPERATION lookupExceptionHandler(ExecState* exec, uint32_t callIndex)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);

    JSValue exceptionValue = exec->exception();
    ASSERT(exceptionValue);
    
    unsigned vPCIndex = exec->codeBlock()->bytecodeOffsetForCallAtIndex(callIndex);
    ExceptionHandler handler = genericThrow(vm, exec, exceptionValue, vPCIndex);
    ASSERT(handler.catchRoutine);
    return dfgHandlerEncoded(handler.callFrame, handler.catchRoutine);
}

DFGHandlerEncoded DFG_OPERATION lookupExceptionHandlerInStub(ExecState* exec, StructureStubInfo* stubInfo)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);

    JSValue exceptionValue = exec->exception();
    ASSERT(exceptionValue);
    
    CodeOrigin codeOrigin = stubInfo->codeOrigin;
    while (codeOrigin.inlineCallFrame)
        codeOrigin = codeOrigin.inlineCallFrame->caller;
    
    ExceptionHandler handler = genericThrow(vm, exec, exceptionValue, codeOrigin.bytecodeIndex);
    ASSERT(handler.catchRoutine);
    return dfgHandlerEncoded(handler.callFrame, handler.catchRoutine);
}

size_t DFG_OPERATION dfgConvertJSValueToInt32(ExecState* exec, EncodedJSValue value)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    // toInt32/toUInt32 return the same value; we want the value zero extended to fill the register.
    return JSValue::decode(value).toUInt32(exec);
}

size_t DFG_OPERATION dfgConvertJSValueToBoolean(ExecState* exec, EncodedJSValue encodedOp)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    return JSValue::decode(encodedOp).toBoolean(exec);
}

void DFG_OPERATION debugOperationPrintSpeculationFailure(ExecState* exec, void* debugInfoRaw, void* scratch)
{
    VM* vm = &exec->vm();
    NativeCallFrameTracer tracer(vm, exec);
    
    SpeculationFailureDebugInfo* debugInfo = static_cast<SpeculationFailureDebugInfo*>(debugInfoRaw);
    CodeBlock* codeBlock = debugInfo->codeBlock;
    CodeBlock* alternative = codeBlock->alternative();
    dataLog(
        "Speculation failure in ", *codeBlock, " with ");
    if (alternative) {
        dataLog(
            "executeCounter = ", alternative->jitExecuteCounter(),
            ", reoptimizationRetryCounter = ", alternative->reoptimizationRetryCounter(),
            ", optimizationDelayCounter = ", alternative->optimizationDelayCounter());
    } else
        dataLog("no alternative code block (i.e. we've been jettisoned)");
    dataLog(", osrExitCounter = ", codeBlock->osrExitCounter(), "\n");
    dataLog("    GPRs at time of exit:");
    char* scratchPointer = static_cast<char*>(scratch);
    for (unsigned i = 0; i < GPRInfo::numberOfRegisters; ++i) {
        GPRReg gpr = GPRInfo::toRegister(i);
        dataLog(" ", GPRInfo::debugName(gpr), ":", RawPointer(*reinterpret_cast_ptr<void**>(scratchPointer)));
        scratchPointer += sizeof(EncodedJSValue);
    }
    dataLog("\n");
    dataLog("    FPRs at time of exit:");
    for (unsigned i = 0; i < FPRInfo::numberOfRegisters; ++i) {
        FPRReg fpr = FPRInfo::toRegister(i);
        dataLog(" ", FPRInfo::debugName(fpr), ":");
        uint64_t bits = *reinterpret_cast_ptr<uint64_t*>(scratchPointer);
        double value = *reinterpret_cast_ptr<double*>(scratchPointer);
        dataLogF("%llx:%lf", static_cast<long long>(bits), value);
        scratchPointer += sizeof(EncodedJSValue);
    }
    dataLog("\n");
}

extern "C" void DFG_OPERATION triggerReoptimizationNow(CodeBlock* codeBlock)
{
#if ENABLE(JIT_VERBOSE_OSR)
    dataLog(*codeBlock, ": Entered reoptimize\n");
#endif
    // We must be called with the baseline code block.
    ASSERT(JITCode::isBaselineCode(codeBlock->getJITType()));

    // If I am my own replacement, then reoptimization has already been triggered.
    // This can happen in recursive functions.
    if (codeBlock->replacement() == codeBlock)
        return;

    // Otherwise, the replacement must be optimized code. Use this as an opportunity
    // to check our logic.
    ASSERT(codeBlock->hasOptimizedReplacement());
    ASSERT(codeBlock->replacement()->getJITType() == JITCode::DFGJIT);

    codeBlock->reoptimize();
}

} // extern "C"
} } // namespace JSC::DFG

#endif // ENABLE(DFG_JIT)

namespace JSC {

#if COMPILER(GCC) && CPU(X86_64)
asm (
".globl " SYMBOL_STRING(getHostCallReturnValue) "\n"
HIDE_SYMBOL(getHostCallReturnValue) "\n"
SYMBOL_STRING(getHostCallReturnValue) ":" "\n"
    "mov -40(%r13), %r13\n"
    "mov %r13, %rdi\n"
    "jmp " LOCAL_REFERENCE(getHostCallReturnValueWithExecState) "\n"
);
#elif COMPILER(GCC) && CPU(X86)
asm (
".text" "\n" \
".globl " SYMBOL_STRING(getHostCallReturnValue) "\n"
HIDE_SYMBOL(getHostCallReturnValue) "\n"
SYMBOL_STRING(getHostCallReturnValue) ":" "\n"
    "mov -40(%edi), %edi\n"
    "mov %edi, 4(%esp)\n"
    "jmp " LOCAL_REFERENCE(getHostCallReturnValueWithExecState) "\n"
);
#elif COMPILER(GCC) && CPU(ARM_THUMB2)
asm (
".text" "\n"
".align 2" "\n"
".globl " SYMBOL_STRING(getHostCallReturnValue) "\n"
HIDE_SYMBOL(getHostCallReturnValue) "\n"
".thumb" "\n"
".thumb_func " THUMB_FUNC_PARAM(getHostCallReturnValue) "\n"
SYMBOL_STRING(getHostCallReturnValue) ":" "\n"
    "ldr r5, [r5, #-40]" "\n"
    "mov r0, r5" "\n"
    "b " LOCAL_REFERENCE(getHostCallReturnValueWithExecState) "\n"
);
#elif COMPILER(GCC) && CPU(ARM_TRADITIONAL)
asm (
".text" "\n"
".globl " SYMBOL_STRING(getHostCallReturnValue) "\n"
HIDE_SYMBOL(getHostCallReturnValue) "\n"
INLINE_ARM_FUNCTION(getHostCallReturnValue)
SYMBOL_STRING(getHostCallReturnValue) ":" "\n"
    "ldr r5, [r5, #-40]" "\n"
    "mov r0, r5" "\n"
    "b " LOCAL_REFERENCE(getHostCallReturnValueWithExecState) "\n"
);
#elif CPU(ARM64)
asm (
".text" "\n"
".align 2" "\n"
".globl " SYMBOL_STRING(getHostCallReturnValue) "\n"
HIDE_SYMBOL(getHostCallReturnValue) "\n"
SYMBOL_STRING(getHostCallReturnValue) ":" "\n"
    "ldur x25, [x25, #-40]" "\n"
    "mov x0, x25" "\n"
    "b " LOCAL_REFERENCE(getHostCallReturnValueWithExecState) "\n"
);
#elif COMPILER(GCC) && CPU(MIPS)
asm(
".text" "\n"
".globl " SYMBOL_STRING(getHostCallReturnValue) "\n"
HIDE_SYMBOL(getHostCallReturnValue) "\n"
SYMBOL_STRING(getHostCallReturnValue) ":" "\n"
    LOAD_FUNCTION_TO_T9(getHostCallReturnValueWithExecState)
    "lw $s0, -40($s0)" "\n"
    "move $a0, $s0" "\n"
    "b " LOCAL_REFERENCE(getHostCallReturnValueWithExecState) "\n"
);
#elif COMPILER(GCC) && CPU(SH4)
asm(
".text" "\n"
".globl " SYMBOL_STRING(getHostCallReturnValue) "\n"
HIDE_SYMBOL(getHostCallReturnValue) "\n"
SYMBOL_STRING(getHostCallReturnValue) ":" "\n"
    "add #-40, r14" "\n"
    "mov.l @r14, r14" "\n"
    "mov r14, r4" "\n"
    "bra " LOCAL_REFERENCE(getHostCallReturnValueWithExecState) "\n"
    "nop" "\n"
);
#endif

extern "C" EncodedJSValue HOST_CALL_RETURN_VALUE_OPTION getHostCallReturnValueWithExecState(ExecState* exec)
{
    if (!exec)
        return JSValue::encode(JSValue());
    return JSValue::encode(exec->vm().hostCallReturnValue);
}

} // namespace JSC

#endif // ENABLE(JIT)