/*

 * Copyright (C) 2008, 2009 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.

 * 3.  Neither the name of Apple Computer, 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.

 *

 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "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 OR ITS CONTRIBUTORS BE LIABLE FOR ANY

 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES

 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

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 */

#include "config.h"

#include "JSActivation.h"

#include "Arguments.h"

#include "Interpreter.h"

#include "JSFunction.h"

namespace JSC {

ASSERT_CLASS_FITS_IN_CELL(JSActivation);

const ClassInfo JSActivation::info = { "JSActivation", 0, 0, 0 };

JSActivation::JSActivation(CallFrame* callFrame, NonNullPassRefPtr<FunctionExecutable> functionExecutable)

    : Base(callFrame->globalData().activationStructure, new JSActivationData(functionExecutable, callFrame->registers()))

{

}

JSActivation::~JSActivation()

{

    delete d();

}

void JSActivation::markChildren(MarkStack& markStack)

{

    Base::markChildren(markStack);

    Register* registerArray = d()->registerArray.get();

    if (!registerArray)

        return;

    size_t numParametersMinusThis = d()->functionExecutable->parameterCount();

    size_t count = numParametersMinusThis;

    markStack.appendValues(registerArray, count);

    size_t numVars = d()->functionExecutable->variableCount();

    // Skip the call frame, which sits between the parameters and vars.

    markStack.appendValues(registerArray + count + RegisterFile::CallFrameHeaderSize, numVars, MayContainNullValues);

}

bool JSActivation::getOwnPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot)

{

    if (propertyName == exec->propertyNames().arguments) {

        slot.setCustom(this, getArgumentsGetter());

        return true;

    }

    if (symbolTableGet(propertyName, slot))

        return true;

    if (JSValue* location = getDirectLocation(propertyName)) {

        slot.setValueSlot(location);

        return true;

    }

    // We don't call through to JSObject because there's no way to give an 

    // activation object getter properties or a prototype.

    ASSERT(!hasGetterSetterProperties());

    ASSERT(prototype().isNull());

    return false;

}

void JSActivation::put(ExecState*, const Identifier& propertyName, JSValue value, PutPropertySlot& slot)

{

    ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(this));

    if (symbolTablePut(propertyName, value))

        return;

    // We don't call through to JSObject because __proto__ and getter/setter 

    // properties are non-standard extensions that other implementations do not

    // expose in the activation object.

    ASSERT(!hasGetterSetterProperties());

    putDirect(propertyName, value, 0, true, slot);

}

// FIXME: Make this function honor ReadOnly (const) and DontEnum

void JSActivation::putWithAttributes(ExecState* exec, const Identifier& propertyName, JSValue value, unsigned attributes)

{

    ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(this));

    if (symbolTablePutWithAttributes(propertyName, value, attributes))

        return;

    // We don't call through to JSObject because __proto__ and getter/setter 

    // properties are non-standard extensions that other implementations do not

    // expose in the activation object.

    ASSERT(!hasGetterSetterProperties());

    PutPropertySlot slot;

    JSObject::putWithAttributes(exec, propertyName, value, attributes, true, slot);

}

bool JSActivation::deleteProperty(ExecState* exec, const Identifier& propertyName)

{

    if (propertyName == exec->propertyNames().arguments)

        return false;

    return Base::deleteProperty(exec, propertyName);

}

JSObject* JSActivation::toThisObject(ExecState* exec) const

{

    return exec->globalThisValue();

}

bool JSActivation::isDynamicScope(bool& requiresDynamicChecks) const

{

    requiresDynamicChecks = d()->functionExecutable->usesEval();

    return false;

}

JSValue JSActivation::argumentsGetter(ExecState*, JSValue slotBase, const Identifier&)

{

    JSActivation* activation = asActivation(slotBase);

    CallFrame* callFrame = CallFrame::create(activation->d()->registers);

    int argumentsRegister = activation->d()->functionExecutable->generatedBytecode().argumentsRegister();

    if (!callFrame->r(argumentsRegister).jsValue()) {

        JSValue arguments = JSValue(new (callFrame) Arguments(callFrame));

        callFrame->r(argumentsRegister) = arguments;

        callFrame->r(unmodifiedArgumentsRegister(argumentsRegister)) = arguments;

    }

    ASSERT(callFrame->r(argumentsRegister).jsValue().inherits(&Arguments::info));

    return callFrame->r(argumentsRegister).jsValue();

}

// These two functions serve the purpose of isolating the common case from a

// PIC branch.

PropertySlot::GetValueFunc JSActivation::getArgumentsGetter()

{

    return argumentsGetter;

}

} // namespace JSC