src/third_party/WebKit/Source/JavaScriptCore/runtime/JSFunction.cpp - cobalt - Git at Google

 /*
  *  Copyright (C) 1999-2002 Harri Porten (porten@kde.org)
  *  Copyright (C) 2001 Peter Kelly (pmk@post.com)
  *  Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
  *  Copyright (C) 2007 Cameron Zwarich (cwzwarich@uwaterloo.ca)
  *  Copyright (C) 2007 Maks Orlovich
  *
  *  This library is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU Library General Public
  *  License as published by the Free Software Foundation; either
  *  version 2 of the License, or (at your option) any later version.
  *
  *  This library is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  *  Library General Public License for more details.
  *
  *  You should have received a copy of the GNU Library General Public License
  *  along with this library; see the file COPYING.LIB.  If not, write to
  *  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  *  Boston, MA 02110-1301, USA.
  *
  */

 #include "config.h"
 #include "JSFunction.h"

 #include "CodeBlock.h"
 #include "CommonIdentifiers.h"
 #include "CallFrame.h"
 #include "ExceptionHelpers.h"
 #include "FunctionPrototype.h"
 #include "GetterSetter.h"
 #include "JSArray.h"
 #include "JSGlobalObject.h"
 #include "JSNotAnObject.h"
 #include "Interpreter.h"
 #include "ObjectPrototype.h"
 #include "Parser.h"
 #include "PropertyNameArray.h"

 using namespace WTF;
 using namespace Unicode;

 namespace JSC {
 EncodedJSValue JSC_HOST_CALL callHostFunctionAsConstructor(ExecState* exec)
 {
     return throwVMError(exec, createNotAConstructorError(exec, exec->callee()));
 }

 const ClassInfo JSFunction::s_info = { "Function", Base::s_classinfo(), 0, 0, CREATE_METHOD_TABLE(JSFunction) };
 const ClassInfo* JSFunction::s_classinfo() { return &s_info; }

 bool JSFunction::isHostFunctionNonInline() const
 {
     return isHostFunction();
 }

 JSFunction* JSFunction::create(ExecState* exec, JSGlobalObject* globalObject, int length, const String& name, NativeFunction nativeFunction, Intrinsic intrinsic, NativeFunction nativeConstructor)
 {
     NativeExecutable* executable;
 #if !ENABLE(JIT)
     UNUSED_PARAM(intrinsic);
 #else
     if (intrinsic != NoIntrinsic && exec->globalData().canUseJIT()) {
         ASSERT(nativeConstructor == callHostFunctionAsConstructor);
         executable = exec->globalData().getHostFunction(nativeFunction, intrinsic);
     } else
 #endif
         executable = exec->globalData().getHostFunction(nativeFunction, nativeConstructor);

     JSFunction* function = new (NotNull, allocateCell<JSFunction>(*exec->heap())) JSFunction(exec, globalObject, globalObject->functionStructure());
     // Can't do this during initialization because getHostFunction might do a GC allocation.
     function->finishCreation(exec, executable, length, name);
     return function;
 }

 void JSFunction::destroyInternal(JSCell* cell)
 {
     static_cast<JSFunction*>(cell)->JSFunction::~JSFunction();
 }

 JSFunction::JSFunction(ExecState* exec, JSGlobalObject* globalObject, Structure* structure)
     : Base(exec->globalData(), structure)
     , m_executable()
     , m_scope(exec->globalData(), this, globalObject)
     // We initialize blind so that changes to the prototype after function creation but before
     // the optimizer kicks in don't disable optimizations. Once the optimizer kicks in, the
     // watchpoint will start watching and any changes will both force deoptimization and disable
     // future attempts to optimize. This is necessary because we are guaranteed that the
     // inheritorID is changed exactly once prior to optimizations kicking in. We could be
     // smarter and count the number of times the prototype is clobbered and only optimize if it
     // was clobbered exactly once, but that seems like overkill. In almost all cases it will be
     // clobbered once, and if it's clobbered more than once, that will probably only occur
     // before we started optimizing, anyway.
     , m_inheritorIDWatchpoint(InitializedBlind)
 {
 }

 void JSFunction::finishCreation(ExecState* exec, NativeExecutable* executable, int length, const String& name)
 {
     Base::finishCreation(exec->globalData());
     ASSERT(inherits(&s_info));
     m_executable.set(exec->globalData(), this, executable);
     putDirect(exec->globalData(), exec->globalData().propertyNames->name, jsString(exec, name), DontDelete | ReadOnly | DontEnum);
     putDirect(exec->globalData(), exec->propertyNames().length, jsNumber(length), DontDelete | ReadOnly | DontEnum);
 }

 Structure* JSFunction::cacheInheritorID(ExecState* exec)
 {
     JSValue prototype = get(exec, exec->globalData().propertyNames->prototype);
     if (prototype.isObject())
         m_cachedInheritorID.set(exec->globalData(), this, asObject(prototype)->inheritorID(exec->globalData()));
     else
         m_cachedInheritorID.set(exec->globalData(), this, globalObject()->emptyObjectStructure());
     return m_cachedInheritorID.get();
 }

 String JSFunction::name(ExecState* exec)
 {
     return get(exec, exec->globalData().propertyNames->name).toWTFString(exec);
 }

 String JSFunction::displayName(ExecState* exec)
 {
     JSValue displayName = getDirect(exec->globalData(), exec->globalData().propertyNames->displayName);

     if (displayName && isJSString(displayName))
         return asString(displayName)->tryGetValue();

     return String();
 }

 const String JSFunction::calculatedDisplayName(ExecState* exec)
 {
     const String explicitName = displayName(exec);

     if (!explicitName.isEmpty())
         return explicitName;

     const String actualName = name(exec);
     if (!actualName.isEmpty() || isHostFunction())
         return actualName;

     return jsExecutable()->inferredName().string();
 }

 const SourceCode* JSFunction::sourceCode() const
 {
     if (isHostFunction())
         return 0;
     return &jsExecutable()->source();
 }

 void JSFunction::visitChildrenInternal(JSCell* cell, SlotVisitor& visitor)
 {
     JSFunction* thisObject = jsCast<JSFunction*>(cell);
     ASSERT_GC_OBJECT_INHERITS(thisObject, &s_info);
     COMPILE_ASSERT(StructureFlags & OverridesVisitChildren, OverridesVisitChildrenWithoutSettingFlag);
     ASSERT(thisObject->structure()->typeInfo().overridesVisitChildren());
     Base::visitChildren(thisObject, visitor);

     visitor.append(&thisObject->m_scope);
     visitor.append(&thisObject->m_executable);
 }

 CallType JSFunction::getCallDataInternal(JSCell* cell, CallData& callData)
 {
     JSFunction* thisObject = jsCast<JSFunction*>(cell);
     if (thisObject->isHostFunction()) {
         callData.native.function = thisObject->nativeFunction();
         return CallTypeHost;
     }
     callData.js.functionExecutable = thisObject->jsExecutable();
     callData.js.scope = thisObject->scope();
     return CallTypeJS;
 }

 JSValue JSFunction::argumentsGetter(ExecState* exec, JSValue slotBase, PropertyName)
 {
     JSFunction* thisObj = jsCast<JSFunction*>(slotBase);
     ASSERT(!thisObj->isHostFunction());
     return exec->interpreter()->retrieveArgumentsFromVMCode(exec, thisObj);
 }

 JSValue JSFunction::callerGetter(ExecState* exec, JSValue slotBase, PropertyName)
 {
     JSFunction* thisObj = jsCast<JSFunction*>(slotBase);
     ASSERT(!thisObj->isHostFunction());
     JSValue caller = exec->interpreter()->retrieveCallerFromVMCode(exec, thisObj);

     // See ES5.1 15.3.5.4 - Function.caller may not be used to retrieve a strict caller.
     if (!caller.isObject() || !asObject(caller)->inherits(&JSFunction::s_info))
         return caller;
     JSFunction* function = jsCast<JSFunction*>(caller);
     if (function->isHostFunction() || !function->jsExecutable()->isStrictMode())
         return caller;
     return throwTypeError(exec, ASCIILiteral("Function.caller used to retrieve strict caller"));
 }

 JSValue JSFunction::lengthGetter(ExecState*, JSValue slotBase, PropertyName)
 {
     JSFunction* thisObj = jsCast<JSFunction*>(slotBase);
     ASSERT(!thisObj->isHostFunction());
     return jsNumber(thisObj->jsExecutable()->parameterCount());
 }

 JSValue JSFunction::nameGetter(ExecState*, JSValue slotBase, PropertyName)
 {
     JSFunction* thisObj = jsCast<JSFunction*>(slotBase);
     ASSERT(!thisObj->isHostFunction());
     return thisObj->jsExecutable()->nameValue();
 }

 bool JSFunction::getOwnPropertySlot(JSCell* cell, ExecState* exec, PropertyName propertyName, PropertySlot& slot)
 {
     JSFunction* thisObject = jsCast<JSFunction*>(cell);
     if (thisObject->isHostFunction())
         return Base::getOwnPropertySlot(thisObject, exec, propertyName, slot);

     if (propertyName == exec->propertyNames().prototype) {
         PropertyOffset offset = thisObject->getDirectOffset(exec->globalData(), propertyName);
         if (!isValidOffset(offset)) {
             JSObject* prototype = constructEmptyObject(exec, thisObject->globalObject()->emptyObjectStructure());
             prototype->putDirect(exec->globalData(), exec->propertyNames().constructor, thisObject, DontEnum);
             thisObject->putDirect(exec->globalData(), exec->propertyNames().prototype, prototype, DontDelete | DontEnum);
             offset = thisObject->getDirectOffset(exec->globalData(), exec->propertyNames().prototype);
             ASSERT(isValidOffset(offset));
         }

         slot.setValue(thisObject, thisObject->getDirect(offset), offset);
     }

     if (propertyName == exec->propertyNames().arguments) {
         if (thisObject->jsExecutable()->isStrictMode()) {
             bool result = Base::getOwnPropertySlot(thisObject, exec, propertyName, slot);
             if (!result) {
                 thisObject->putDirectAccessor(exec, propertyName, thisObject->globalObject()->throwTypeErrorGetterSetter(exec), DontDelete | DontEnum | Accessor);
                 result = Base::getOwnPropertySlot(thisObject, exec, propertyName, slot);
                 ASSERT(result);
             }
             return result;
         }
         slot.setCacheableCustom(thisObject, argumentsGetter);
         return true;
     }

     if (propertyName == exec->propertyNames().length) {
         slot.setCacheableCustom(thisObject, lengthGetter);
         return true;
     }

     if (propertyName == exec->propertyNames().name) {
         slot.setCacheableCustom(thisObject, nameGetter);
         return true;
     }

     if (propertyName == exec->propertyNames().caller) {
         if (thisObject->jsExecutable()->isStrictMode()) {
             bool result = Base::getOwnPropertySlot(thisObject, exec, propertyName, slot);
             if (!result) {
                 thisObject->putDirectAccessor(exec, propertyName, thisObject->globalObject()->throwTypeErrorGetterSetter(exec), DontDelete | DontEnum | Accessor);
                 result = Base::getOwnPropertySlot(thisObject, exec, propertyName, slot);
                 ASSERT(result);
             }
             return result;
         }
         slot.setCacheableCustom(thisObject, callerGetter);
         return true;
     }

     return Base::getOwnPropertySlot(thisObject, exec, propertyName, slot);
 }

 bool JSFunction::getOwnPropertyDescriptorInternal(JSObject* object, ExecState* exec, PropertyName propertyName, PropertyDescriptor& descriptor)
 {
     JSFunction* thisObject = jsCast<JSFunction*>(object);
     if (thisObject->isHostFunction())
         return Base::getOwnPropertyDescriptor(thisObject, exec, propertyName, descriptor);

     if (propertyName == exec->propertyNames().prototype) {
         PropertySlot slot;
         thisObject->methodTable()->getOwnPropertySlot(thisObject, exec, propertyName, slot);
         return Base::getOwnPropertyDescriptor(thisObject, exec, propertyName, descriptor);
     }

     if (propertyName == exec->propertyNames().arguments) {
         if (thisObject->jsExecutable()->isStrictMode()) {
             bool result = Base::getOwnPropertyDescriptor(thisObject, exec, propertyName, descriptor);
             if (!result) {
                 thisObject->putDirectAccessor(exec, propertyName, thisObject->globalObject()->throwTypeErrorGetterSetter(exec), DontDelete | DontEnum | Accessor);
                 result = Base::getOwnPropertyDescriptor(thisObject, exec, propertyName, descriptor);
                 ASSERT(result);
             }
             return result;
         }
         descriptor.setDescriptor(exec->interpreter()->retrieveArgumentsFromVMCode(exec, thisObject), ReadOnly | DontEnum | DontDelete);
         return true;
     }

     if (propertyName == exec->propertyNames().length) {
         descriptor.setDescriptor(jsNumber(thisObject->jsExecutable()->parameterCount()), ReadOnly | DontEnum | DontDelete);
         return true;
     }

     if (propertyName == exec->propertyNames().name) {
         descriptor.setDescriptor(thisObject->jsExecutable()->nameValue(), ReadOnly | DontEnum | DontDelete);
         return true;
     }

     if (propertyName == exec->propertyNames().caller) {
         if (thisObject->jsExecutable()->isStrictMode()) {
             bool result = Base::getOwnPropertyDescriptor(thisObject, exec, propertyName, descriptor);
             if (!result) {
                 thisObject->putDirectAccessor(exec, propertyName, thisObject->globalObject()->throwTypeErrorGetterSetter(exec), DontDelete | DontEnum | Accessor);
                 result = Base::getOwnPropertyDescriptor(thisObject, exec, propertyName, descriptor);
                 ASSERT(result);
             }
             return result;
         }
         descriptor.setDescriptor(exec->interpreter()->retrieveCallerFromVMCode(exec, thisObject), ReadOnly | DontEnum | DontDelete);
         return true;
     }

     return Base::getOwnPropertyDescriptor(thisObject, exec, propertyName, descriptor);
 }

 void JSFunction::getOwnNonIndexPropertyNamesInternal(JSObject* object, ExecState* exec, PropertyNameArray& propertyNames, EnumerationMode mode)
 {
     JSFunction* thisObject = jsCast<JSFunction*>(object);
     if (!thisObject->isHostFunction() && (mode == IncludeDontEnumProperties)) {
         // Make sure prototype has been reified.
         PropertySlot slot;
         thisObject->methodTable()->getOwnPropertySlot(thisObject, exec, exec->propertyNames().prototype, slot);

         propertyNames.add(exec->propertyNames().arguments);
         propertyNames.add(exec->propertyNames().caller);
         propertyNames.add(exec->propertyNames().length);
         propertyNames.add(exec->propertyNames().name);
     }
     Base::getOwnNonIndexPropertyNames(thisObject, exec, propertyNames, mode);
 }

 void JSFunction::putInternal(JSCell* cell, ExecState* exec, PropertyName propertyName, JSValue value, PutPropertySlot& slot)
 {
     JSFunction* thisObject = jsCast<JSFunction*>(cell);
     if (thisObject->isHostFunction()) {
         Base::put(thisObject, exec, propertyName, value, slot);
         return;
     }
     if (propertyName == exec->propertyNames().prototype) {
         // Make sure prototype has been reified, such that it can only be overwritten
         // following the rules set out in ECMA-262 8.12.9.
         PropertySlot slot;
         thisObject->methodTable()->getOwnPropertySlot(thisObject, exec, propertyName, slot);
         thisObject->m_cachedInheritorID.clear();
         thisObject->m_inheritorIDWatchpoint.notifyWrite();
         // Don't allow this to be cached, since a [[Put]] must clear m_cachedInheritorID.
         PutPropertySlot dontCache;
         Base::put(thisObject, exec, propertyName, value, dontCache);
         return;
     }
     if (thisObject->jsExecutable()->isStrictMode() && (propertyName == exec->propertyNames().arguments || propertyName == exec->propertyNames().caller)) {
         // This will trigger the property to be reified, if this is not already the case!
         bool okay = thisObject->hasProperty(exec, propertyName);
         ASSERT_UNUSED(okay, okay);
         Base::put(thisObject, exec, propertyName, value, slot);
         return;
     }
     if (propertyName == exec->propertyNames().arguments || propertyName == exec->propertyNames().length || propertyName == exec->propertyNames().name || propertyName == exec->propertyNames().caller) {
         if (slot.isStrictMode())
             throwTypeError(exec, GetStrictModeReadonlyPropertyWriteError());
         return;
     }
     Base::put(thisObject, exec, propertyName, value, slot);
 }

 bool JSFunction::deletePropertyInternal(JSCell* cell, ExecState* exec, PropertyName propertyName)
 {
     JSFunction* thisObject = jsCast<JSFunction*>(cell);
     // For non-host functions, don't let these properties by deleted - except by DefineOwnProperty.
     if (!thisObject->isHostFunction() && !exec->globalData().isInDefineOwnProperty()
         && (propertyName == exec->propertyNames().arguments
             || propertyName == exec->propertyNames().length
             || propertyName == exec->propertyNames().name
             || propertyName == exec->propertyNames().prototype
             || propertyName == exec->propertyNames().caller))
         return false;
     return Base::deleteProperty(thisObject, exec, propertyName);
 }

 bool JSFunction::defineOwnPropertyInternal(JSObject* object, ExecState* exec, PropertyName propertyName, PropertyDescriptor& descriptor, bool throwException)
 {
     JSFunction* thisObject = jsCast<JSFunction*>(object);
     if (thisObject->isHostFunction())
         return Base::defineOwnProperty(object, exec, propertyName, descriptor, throwException);

     if (propertyName == exec->propertyNames().prototype) {
         // Make sure prototype has been reified, such that it can only be overwritten
         // following the rules set out in ECMA-262 8.12.9.
         PropertySlot slot;
         thisObject->methodTable()->getOwnPropertySlot(thisObject, exec, propertyName, slot);
         thisObject->m_cachedInheritorID.clear();
         thisObject->m_inheritorIDWatchpoint.notifyWrite();
         return Base::defineOwnProperty(object, exec, propertyName, descriptor, throwException);
     }

     bool valueCheck;
     if (propertyName == exec->propertyNames().arguments) {
         if (thisObject->jsExecutable()->isStrictMode()) {
             if (!Base::getOwnPropertyDescriptor(thisObject, exec, propertyName, descriptor))
                 thisObject->putDirectAccessor(exec, propertyName, thisObject->globalObject()->throwTypeErrorGetterSetter(exec), DontDelete | DontEnum | Accessor);
             return Base::defineOwnProperty(object, exec, propertyName, descriptor, throwException);
         }
         valueCheck = !descriptor.value() || sameValue(exec, descriptor.value(), exec->interpreter()->retrieveArgumentsFromVMCode(exec, thisObject));
     } else if (propertyName == exec->propertyNames().caller) {
         if (thisObject->jsExecutable()->isStrictMode()) {
             if (!Base::getOwnPropertyDescriptor(thisObject, exec, propertyName, descriptor))
                 thisObject->putDirectAccessor(exec, propertyName, thisObject->globalObject()->throwTypeErrorGetterSetter(exec), DontDelete | DontEnum | Accessor);
             return Base::defineOwnProperty(object, exec, propertyName, descriptor, throwException);
         }
         valueCheck = !descriptor.value() || sameValue(exec, descriptor.value(), exec->interpreter()->retrieveCallerFromVMCode(exec, thisObject));
     } else if (propertyName == exec->propertyNames().length)
         valueCheck = !descriptor.value() || sameValue(exec, descriptor.value(), jsNumber(thisObject->jsExecutable()->parameterCount()));
     else if (propertyName == exec->propertyNames().name)
         valueCheck = !descriptor.value() || sameValue(exec, descriptor.value(), thisObject->jsExecutable()->nameValue());
     else
         return Base::defineOwnProperty(object, exec, propertyName, descriptor, throwException);

     if (descriptor.configurablePresent() && descriptor.configurable()) {
         if (throwException)
             throwError(exec, createTypeError(exec, ASCIILiteral("Attempting to configurable attribute of unconfigurable property.")));
         return false;
     }
     if (descriptor.enumerablePresent() && descriptor.enumerable()) {
         if (throwException)
             throwError(exec, createTypeError(exec, ASCIILiteral("Attempting to change enumerable attribute of unconfigurable property.")));
         return false;
     }
     if (descriptor.isAccessorDescriptor()) {
         if (throwException)
             throwError(exec, createTypeError(exec, ASCIILiteral("Attempting to change access mechanism for an unconfigurable property.")));
         return false;
     }
     if (descriptor.writablePresent() && descriptor.writable()) {
         if (throwException)
             throwError(exec, createTypeError(exec, ASCIILiteral("Attempting to change writable attribute of unconfigurable property.")));
         return false;
     }
     if (!valueCheck) {
         if (throwException)
             throwError(exec, createTypeError(exec, ASCIILiteral("Attempting to change value of a readonly property.")));
         return false;
     }
     return true;
 }

 // ECMA 13.2.2 [[Construct]]
 ConstructType JSFunction::getConstructDataInternal(JSCell* cell, ConstructData& constructData)
 {
     JSFunction* thisObject = jsCast<JSFunction*>(cell);
     if (thisObject->isHostFunction()) {
         constructData.native.function = thisObject->nativeConstructor();
         return ConstructTypeHost;
     }
     constructData.js.functionExecutable = thisObject->jsExecutable();
     constructData.js.scope = thisObject->scope();
     return ConstructTypeJS;
 }


 String getCalculatedDisplayName(CallFrame* callFrame, JSObject* object)
 {
     if (JSFunction* function = jsDynamicCast<JSFunction*>(object))
         return function->calculatedDisplayName(callFrame);
     if (InternalFunction* function = jsDynamicCast<InternalFunction*>(object))
         return function->calculatedDisplayName(callFrame);
     return "";
 }

 } // namespace JSC
	/*
	* Copyright (C) 1999-2002 Harri Porten (porten@kde.org)
	* Copyright (C) 2001 Peter Kelly (pmk@post.com)
	* Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
	* Copyright (C) 2007 Cameron Zwarich (cwzwarich@uwaterloo.ca)
	* Copyright (C) 2007 Maks Orlovich
	*
	* This library is free software; you can redistribute it and/or
	* modify it under the terms of the GNU Library General Public
	* License as published by the Free Software Foundation; either
	* version 2 of the License, or (at your option) any later version.
	*
	* This library is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* Library General Public License for more details.
	*
	* You should have received a copy of the GNU Library General Public License
	* along with this library; see the file COPYING.LIB. If not, write to
	* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
	* Boston, MA 02110-1301, USA.
	*
	*/

	#include "config.h"
	#include "JSFunction.h"

	#include "CodeBlock.h"
	#include "CommonIdentifiers.h"
	#include "CallFrame.h"
	#include "ExceptionHelpers.h"
	#include "FunctionPrototype.h"
	#include "GetterSetter.h"
	#include "JSArray.h"
	#include "JSGlobalObject.h"
	#include "JSNotAnObject.h"
	#include "Interpreter.h"
	#include "ObjectPrototype.h"
	#include "Parser.h"
	#include "PropertyNameArray.h"

	using namespace WTF;
	using namespace Unicode;

	namespace JSC {
	EncodedJSValue JSC_HOST_CALL callHostFunctionAsConstructor(ExecState* exec)
	{
	return throwVMError(exec, createNotAConstructorError(exec, exec->callee()));
	}

	const ClassInfo JSFunction::s_info = { "Function", Base::s_classinfo(), 0, 0, CREATE_METHOD_TABLE(JSFunction) };
	const ClassInfo* JSFunction::s_classinfo() { return &s_info; }

	bool JSFunction::isHostFunctionNonInline() const
	{
	return isHostFunction();
	}

	JSFunction* JSFunction::create(ExecState* exec, JSGlobalObject* globalObject, int length, const String& name, NativeFunction nativeFunction, Intrinsic intrinsic, NativeFunction nativeConstructor)
	{
	NativeExecutable* executable;
	#if !ENABLE(JIT)
	UNUSED_PARAM(intrinsic);
	#else
	if (intrinsic != NoIntrinsic && exec->globalData().canUseJIT()) {
	ASSERT(nativeConstructor == callHostFunctionAsConstructor);
	executable = exec->globalData().getHostFunction(nativeFunction, intrinsic);
	} else
	#endif
	executable = exec->globalData().getHostFunction(nativeFunction, nativeConstructor);

	JSFunction* function = new (NotNull, allocateCell<JSFunction>(*exec->heap())) JSFunction(exec, globalObject, globalObject->functionStructure());
	// Can't do this during initialization because getHostFunction might do a GC allocation.
	function->finishCreation(exec, executable, length, name);
	return function;
	}

	void JSFunction::destroyInternal(JSCell* cell)
	{
	static_cast<JSFunction*>(cell)->JSFunction::~JSFunction();
	}

	JSFunction::JSFunction(ExecState* exec, JSGlobalObject* globalObject, Structure* structure)
	: Base(exec->globalData(), structure)
	, m_executable()
	, m_scope(exec->globalData(), this, globalObject)
	// We initialize blind so that changes to the prototype after function creation but before
	// the optimizer kicks in don't disable optimizations. Once the optimizer kicks in, the
	// watchpoint will start watching and any changes will both force deoptimization and disable
	// future attempts to optimize. This is necessary because we are guaranteed that the
	// inheritorID is changed exactly once prior to optimizations kicking in. We could be
	// smarter and count the number of times the prototype is clobbered and only optimize if it
	// was clobbered exactly once, but that seems like overkill. In almost all cases it will be
	// clobbered once, and if it's clobbered more than once, that will probably only occur
	// before we started optimizing, anyway.
	, m_inheritorIDWatchpoint(InitializedBlind)
	{
	}

	void JSFunction::finishCreation(ExecState* exec, NativeExecutable* executable, int length, const String& name)
	{
	Base::finishCreation(exec->globalData());
	ASSERT(inherits(&s_info));
	m_executable.set(exec->globalData(), this, executable);
	putDirect(exec->globalData(), exec->globalData().propertyNames->name, jsString(exec, name), DontDelete \| ReadOnly \| DontEnum);
	putDirect(exec->globalData(), exec->propertyNames().length, jsNumber(length), DontDelete \| ReadOnly \| DontEnum);
	}

	Structure* JSFunction::cacheInheritorID(ExecState* exec)
	{
	JSValue prototype = get(exec, exec->globalData().propertyNames->prototype);
	if (prototype.isObject())
	m_cachedInheritorID.set(exec->globalData(), this, asObject(prototype)->inheritorID(exec->globalData()));
	else
	m_cachedInheritorID.set(exec->globalData(), this, globalObject()->emptyObjectStructure());
	return m_cachedInheritorID.get();
	}

	String JSFunction::name(ExecState* exec)
	{
	return get(exec, exec->globalData().propertyNames->name).toWTFString(exec);
	}

	String JSFunction::displayName(ExecState* exec)
	{
	JSValue displayName = getDirect(exec->globalData(), exec->globalData().propertyNames->displayName);

	if (displayName && isJSString(displayName))
	return asString(displayName)->tryGetValue();

	return String();
	}

	const String JSFunction::calculatedDisplayName(ExecState* exec)
	{
	const String explicitName = displayName(exec);

	if (!explicitName.isEmpty())
	return explicitName;

	const String actualName = name(exec);
	if (!actualName.isEmpty() \|\| isHostFunction())
	return actualName;

	return jsExecutable()->inferredName().string();
	}

	const SourceCode* JSFunction::sourceCode() const
	{
	if (isHostFunction())
	return 0;
	return &jsExecutable()->source();
	}

	void JSFunction::visitChildrenInternal(JSCell* cell, SlotVisitor& visitor)
	{
	JSFunction* thisObject = jsCast<JSFunction*>(cell);
	ASSERT_GC_OBJECT_INHERITS(thisObject, &s_info);
	COMPILE_ASSERT(StructureFlags & OverridesVisitChildren, OverridesVisitChildrenWithoutSettingFlag);
	ASSERT(thisObject->structure()->typeInfo().overridesVisitChildren());
	Base::visitChildren(thisObject, visitor);

	visitor.append(&thisObject->m_scope);
	visitor.append(&thisObject->m_executable);
	}

	CallType JSFunction::getCallDataInternal(JSCell* cell, CallData& callData)
	{
	JSFunction* thisObject = jsCast<JSFunction*>(cell);
	if (thisObject->isHostFunction()) {
	callData.native.function = thisObject->nativeFunction();
	return CallTypeHost;
	}
	callData.js.functionExecutable = thisObject->jsExecutable();
	callData.js.scope = thisObject->scope();
	return CallTypeJS;
	}

	JSValue JSFunction::argumentsGetter(ExecState* exec, JSValue slotBase, PropertyName)
	{
	JSFunction* thisObj = jsCast<JSFunction*>(slotBase);
	ASSERT(!thisObj->isHostFunction());
	return exec->interpreter()->retrieveArgumentsFromVMCode(exec, thisObj);
	}

	JSValue JSFunction::callerGetter(ExecState* exec, JSValue slotBase, PropertyName)
	{
	JSFunction* thisObj = jsCast<JSFunction*>(slotBase);
	ASSERT(!thisObj->isHostFunction());
	JSValue caller = exec->interpreter()->retrieveCallerFromVMCode(exec, thisObj);

	// See ES5.1 15.3.5.4 - Function.caller may not be used to retrieve a strict caller.
	if (!caller.isObject() \|\| !asObject(caller)->inherits(&JSFunction::s_info))
	return caller;
	JSFunction* function = jsCast<JSFunction*>(caller);
	if (function->isHostFunction() \|\| !function->jsExecutable()->isStrictMode())
	return caller;
	return throwTypeError(exec, ASCIILiteral("Function.caller used to retrieve strict caller"));
	}

	JSValue JSFunction::lengthGetter(ExecState*, JSValue slotBase, PropertyName)
	{
	JSFunction* thisObj = jsCast<JSFunction*>(slotBase);
	ASSERT(!thisObj->isHostFunction());
	return jsNumber(thisObj->jsExecutable()->parameterCount());
	}

	JSValue JSFunction::nameGetter(ExecState*, JSValue slotBase, PropertyName)
	{
	JSFunction* thisObj = jsCast<JSFunction*>(slotBase);
	ASSERT(!thisObj->isHostFunction());
	return thisObj->jsExecutable()->nameValue();
	}

	bool JSFunction::getOwnPropertySlot(JSCell* cell, ExecState* exec, PropertyName propertyName, PropertySlot& slot)
	{
	JSFunction* thisObject = jsCast<JSFunction*>(cell);
	if (thisObject->isHostFunction())
	return Base::getOwnPropertySlot(thisObject, exec, propertyName, slot);

	if (propertyName == exec->propertyNames().prototype) {
	PropertyOffset offset = thisObject->getDirectOffset(exec->globalData(), propertyName);
	if (!isValidOffset(offset)) {
	JSObject* prototype = constructEmptyObject(exec, thisObject->globalObject()->emptyObjectStructure());
	prototype->putDirect(exec->globalData(), exec->propertyNames().constructor, thisObject, DontEnum);
	thisObject->putDirect(exec->globalData(), exec->propertyNames().prototype, prototype, DontDelete \| DontEnum);
	offset = thisObject->getDirectOffset(exec->globalData(), exec->propertyNames().prototype);
	ASSERT(isValidOffset(offset));
	}

	slot.setValue(thisObject, thisObject->getDirect(offset), offset);
	}

	if (propertyName == exec->propertyNames().arguments) {
	if (thisObject->jsExecutable()->isStrictMode()) {
	bool result = Base::getOwnPropertySlot(thisObject, exec, propertyName, slot);
	if (!result) {
	thisObject->putDirectAccessor(exec, propertyName, thisObject->globalObject()->throwTypeErrorGetterSetter(exec), DontDelete \| DontEnum \| Accessor);
	result = Base::getOwnPropertySlot(thisObject, exec, propertyName, slot);
	ASSERT(result);
	}
	return result;
	}
	slot.setCacheableCustom(thisObject, argumentsGetter);
	return true;
	}

	if (propertyName == exec->propertyNames().length) {
	slot.setCacheableCustom(thisObject, lengthGetter);
	return true;
	}

	if (propertyName == exec->propertyNames().name) {
	slot.setCacheableCustom(thisObject, nameGetter);
	return true;
	}

	if (propertyName == exec->propertyNames().caller) {
	if (thisObject->jsExecutable()->isStrictMode()) {
	bool result = Base::getOwnPropertySlot(thisObject, exec, propertyName, slot);
	if (!result) {
	thisObject->putDirectAccessor(exec, propertyName, thisObject->globalObject()->throwTypeErrorGetterSetter(exec), DontDelete \| DontEnum \| Accessor);
	result = Base::getOwnPropertySlot(thisObject, exec, propertyName, slot);
	ASSERT(result);
	}
	return result;
	}
	slot.setCacheableCustom(thisObject, callerGetter);
	return true;
	}

	return Base::getOwnPropertySlot(thisObject, exec, propertyName, slot);
	}

	bool JSFunction::getOwnPropertyDescriptorInternal(JSObject* object, ExecState* exec, PropertyName propertyName, PropertyDescriptor& descriptor)
	{
	JSFunction* thisObject = jsCast<JSFunction*>(object);
	if (thisObject->isHostFunction())
	return Base::getOwnPropertyDescriptor(thisObject, exec, propertyName, descriptor);

	if (propertyName == exec->propertyNames().prototype) {
	PropertySlot slot;
	thisObject->methodTable()->getOwnPropertySlot(thisObject, exec, propertyName, slot);
	return Base::getOwnPropertyDescriptor(thisObject, exec, propertyName, descriptor);
	}

	if (propertyName == exec->propertyNames().arguments) {
	if (thisObject->jsExecutable()->isStrictMode()) {
	bool result = Base::getOwnPropertyDescriptor(thisObject, exec, propertyName, descriptor);
	if (!result) {
	thisObject->putDirectAccessor(exec, propertyName, thisObject->globalObject()->throwTypeErrorGetterSetter(exec), DontDelete \| DontEnum \| Accessor);
	result = Base::getOwnPropertyDescriptor(thisObject, exec, propertyName, descriptor);
	ASSERT(result);
	}
	return result;
	}
	descriptor.setDescriptor(exec->interpreter()->retrieveArgumentsFromVMCode(exec, thisObject), ReadOnly \| DontEnum \| DontDelete);
	return true;
	}

	if (propertyName == exec->propertyNames().length) {
	descriptor.setDescriptor(jsNumber(thisObject->jsExecutable()->parameterCount()), ReadOnly \| DontEnum \| DontDelete);
	return true;
	}

	if (propertyName == exec->propertyNames().name) {
	descriptor.setDescriptor(thisObject->jsExecutable()->nameValue(), ReadOnly \| DontEnum \| DontDelete);
	return true;
	}

	if (propertyName == exec->propertyNames().caller) {
	if (thisObject->jsExecutable()->isStrictMode()) {
	bool result = Base::getOwnPropertyDescriptor(thisObject, exec, propertyName, descriptor);
	if (!result) {
	thisObject->putDirectAccessor(exec, propertyName, thisObject->globalObject()->throwTypeErrorGetterSetter(exec), DontDelete \| DontEnum \| Accessor);
	result = Base::getOwnPropertyDescriptor(thisObject, exec, propertyName, descriptor);
	ASSERT(result);
	}
	return result;
	}
	descriptor.setDescriptor(exec->interpreter()->retrieveCallerFromVMCode(exec, thisObject), ReadOnly \| DontEnum \| DontDelete);
	return true;
	}

	return Base::getOwnPropertyDescriptor(thisObject, exec, propertyName, descriptor);
	}

	void JSFunction::getOwnNonIndexPropertyNamesInternal(JSObject* object, ExecState* exec, PropertyNameArray& propertyNames, EnumerationMode mode)
	{
	JSFunction* thisObject = jsCast<JSFunction*>(object);
	if (!thisObject->isHostFunction() && (mode == IncludeDontEnumProperties)) {
	// Make sure prototype has been reified.
	PropertySlot slot;
	thisObject->methodTable()->getOwnPropertySlot(thisObject, exec, exec->propertyNames().prototype, slot);

	propertyNames.add(exec->propertyNames().arguments);
	propertyNames.add(exec->propertyNames().caller);
	propertyNames.add(exec->propertyNames().length);
	propertyNames.add(exec->propertyNames().name);
	}
	Base::getOwnNonIndexPropertyNames(thisObject, exec, propertyNames, mode);
	}

	void JSFunction::putInternal(JSCell* cell, ExecState* exec, PropertyName propertyName, JSValue value, PutPropertySlot& slot)
	{
	JSFunction* thisObject = jsCast<JSFunction*>(cell);
	if (thisObject->isHostFunction()) {
	Base::put(thisObject, exec, propertyName, value, slot);
	return;
	}
	if (propertyName == exec->propertyNames().prototype) {
	// Make sure prototype has been reified, such that it can only be overwritten
	// following the rules set out in ECMA-262 8.12.9.
	PropertySlot slot;
	thisObject->methodTable()->getOwnPropertySlot(thisObject, exec, propertyName, slot);
	thisObject->m_cachedInheritorID.clear();
	thisObject->m_inheritorIDWatchpoint.notifyWrite();
	// Don't allow this to be cached, since a [[Put]] must clear m_cachedInheritorID.
	PutPropertySlot dontCache;
	Base::put(thisObject, exec, propertyName, value, dontCache);
	return;
	}
	if (thisObject->jsExecutable()->isStrictMode() && (propertyName == exec->propertyNames().arguments \|\| propertyName == exec->propertyNames().caller)) {
	// This will trigger the property to be reified, if this is not already the case!
	bool okay = thisObject->hasProperty(exec, propertyName);
	ASSERT_UNUSED(okay, okay);
	Base::put(thisObject, exec, propertyName, value, slot);
	return;
	}
	if (propertyName == exec->propertyNames().arguments \|\| propertyName == exec->propertyNames().length \|\| propertyName == exec->propertyNames().name \|\| propertyName == exec->propertyNames().caller) {
	if (slot.isStrictMode())
	throwTypeError(exec, GetStrictModeReadonlyPropertyWriteError());
	return;
	}
	Base::put(thisObject, exec, propertyName, value, slot);
	}

	bool JSFunction::deletePropertyInternal(JSCell* cell, ExecState* exec, PropertyName propertyName)
	{
	JSFunction* thisObject = jsCast<JSFunction*>(cell);
	// For non-host functions, don't let these properties by deleted - except by DefineOwnProperty.
	if (!thisObject->isHostFunction() && !exec->globalData().isInDefineOwnProperty()
	&& (propertyName == exec->propertyNames().arguments
	\|\| propertyName == exec->propertyNames().length
	\|\| propertyName == exec->propertyNames().name
	\|\| propertyName == exec->propertyNames().prototype
	\|\| propertyName == exec->propertyNames().caller))
	return false;
	return Base::deleteProperty(thisObject, exec, propertyName);
	}

	bool JSFunction::defineOwnPropertyInternal(JSObject* object, ExecState* exec, PropertyName propertyName, PropertyDescriptor& descriptor, bool throwException)
	{
	JSFunction* thisObject = jsCast<JSFunction*>(object);
	if (thisObject->isHostFunction())
	return Base::defineOwnProperty(object, exec, propertyName, descriptor, throwException);

	if (propertyName == exec->propertyNames().prototype) {
	// Make sure prototype has been reified, such that it can only be overwritten
	// following the rules set out in ECMA-262 8.12.9.
	PropertySlot slot;
	thisObject->methodTable()->getOwnPropertySlot(thisObject, exec, propertyName, slot);
	thisObject->m_cachedInheritorID.clear();
	thisObject->m_inheritorIDWatchpoint.notifyWrite();
	return Base::defineOwnProperty(object, exec, propertyName, descriptor, throwException);
	}

	bool valueCheck;
	if (propertyName == exec->propertyNames().arguments) {
	if (thisObject->jsExecutable()->isStrictMode()) {
	if (!Base::getOwnPropertyDescriptor(thisObject, exec, propertyName, descriptor))
	thisObject->putDirectAccessor(exec, propertyName, thisObject->globalObject()->throwTypeErrorGetterSetter(exec), DontDelete \| DontEnum \| Accessor);
	return Base::defineOwnProperty(object, exec, propertyName, descriptor, throwException);
	}
	valueCheck = !descriptor.value() \|\| sameValue(exec, descriptor.value(), exec->interpreter()->retrieveArgumentsFromVMCode(exec, thisObject));
	} else if (propertyName == exec->propertyNames().caller) {
	if (thisObject->jsExecutable()->isStrictMode()) {
	if (!Base::getOwnPropertyDescriptor(thisObject, exec, propertyName, descriptor))
	thisObject->putDirectAccessor(exec, propertyName, thisObject->globalObject()->throwTypeErrorGetterSetter(exec), DontDelete \| DontEnum \| Accessor);
	return Base::defineOwnProperty(object, exec, propertyName, descriptor, throwException);
	}
	valueCheck = !descriptor.value() \|\| sameValue(exec, descriptor.value(), exec->interpreter()->retrieveCallerFromVMCode(exec, thisObject));
	} else if (propertyName == exec->propertyNames().length)
	valueCheck = !descriptor.value() \|\| sameValue(exec, descriptor.value(), jsNumber(thisObject->jsExecutable()->parameterCount()));
	else if (propertyName == exec->propertyNames().name)
	valueCheck = !descriptor.value() \|\| sameValue(exec, descriptor.value(), thisObject->jsExecutable()->nameValue());
	else
	return Base::defineOwnProperty(object, exec, propertyName, descriptor, throwException);

	if (descriptor.configurablePresent() && descriptor.configurable()) {
	if (throwException)
	throwError(exec, createTypeError(exec, ASCIILiteral("Attempting to configurable attribute of unconfigurable property.")));
	return false;
	}
	if (descriptor.enumerablePresent() && descriptor.enumerable()) {
	if (throwException)
	throwError(exec, createTypeError(exec, ASCIILiteral("Attempting to change enumerable attribute of unconfigurable property.")));
	return false;
	}
	if (descriptor.isAccessorDescriptor()) {
	if (throwException)
	throwError(exec, createTypeError(exec, ASCIILiteral("Attempting to change access mechanism for an unconfigurable property.")));
	return false;
	}
	if (descriptor.writablePresent() && descriptor.writable()) {
	if (throwException)
	throwError(exec, createTypeError(exec, ASCIILiteral("Attempting to change writable attribute of unconfigurable property.")));
	return false;
	}
	if (!valueCheck) {
	if (throwException)
	throwError(exec, createTypeError(exec, ASCIILiteral("Attempting to change value of a readonly property.")));
	return false;
	}
	return true;
	}

	// ECMA 13.2.2 [[Construct]]
	ConstructType JSFunction::getConstructDataInternal(JSCell* cell, ConstructData& constructData)
	{
	JSFunction* thisObject = jsCast<JSFunction*>(cell);
	if (thisObject->isHostFunction()) {
	constructData.native.function = thisObject->nativeConstructor();
	return ConstructTypeHost;
	}
	constructData.js.functionExecutable = thisObject->jsExecutable();
	constructData.js.scope = thisObject->scope();
	return ConstructTypeJS;
	}


	String getCalculatedDisplayName(CallFrame* callFrame, JSObject* object)
	{
	if (JSFunction* function = jsDynamicCast<JSFunction*>(object))
	return function->calculatedDisplayName(callFrame);
	if (InternalFunction* function = jsDynamicCast<InternalFunction*>(object))
	return function->calculatedDisplayName(callFrame);
	return "";
	}

	} // namespace JSC