| /* | 
 |  *  Copyright (C) 1999-2002 Harri Porten (porten@kde.org) | 
 |  *  Copyright (C) 2001 Peter Kelly (pmk@post.com) | 
 |  *  Copyright (C) 2003-2020 Apple Inc. All rights reserved. | 
 |  *  Copyright (C) 2007 Cameron Zwarich (cwzwarich@uwaterloo.ca) | 
 |  *  Copyright (C) 2007 Maks Orlovich | 
 |  *  Copyright (C) 2015 Canon Inc. All rights reserved. | 
 |  * | 
 |  *  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 "AsyncGeneratorPrototype.h" | 
 | #include "BuiltinNames.h" | 
 | #include "CatchScope.h" | 
 | #include "ClonedArguments.h" | 
 | #include "CommonIdentifiers.h" | 
 | #include "CallFrame.h" | 
 | #include "GeneratorPrototype.h" | 
 | #include "JSBoundFunction.h" | 
 | #include "JSCInlines.h" | 
 | #include "JSGlobalObject.h" | 
 | #include "JSToWasmICCallee.h" | 
 | #include "ObjectConstructor.h" | 
 | #include "ObjectPrototype.h" | 
 | #include "PropertyNameArray.h" | 
 | #include "StackVisitor.h" | 
 | #include "TypeError.h" | 
 |  | 
 | namespace JSC { | 
 |  | 
 | JSC_DEFINE_HOST_FUNCTION(callHostFunctionAsConstructor, (JSGlobalObject* globalObject, CallFrame* callFrame)) | 
 | { | 
 |     VM& vm = globalObject->vm(); | 
 |     auto scope = DECLARE_THROW_SCOPE(vm); | 
 |     return throwVMError(globalObject, scope, createNotAConstructorError(globalObject, callFrame->jsCallee())); | 
 | } | 
 |  | 
 | static JSC_DECLARE_CUSTOM_GETTER(argumentsGetter); | 
 | static JSC_DECLARE_CUSTOM_GETTER(callerGetter); | 
 |  | 
 | const ClassInfo JSFunction::s_info = { "Function", &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(JSFunction) }; | 
 | const ClassInfo JSStrictFunction::s_info = { "Function", &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(JSStrictFunction) }; | 
 | const ClassInfo JSSloppyFunction::s_info = { "Function", &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(JSSloppyFunction) }; | 
 | const ClassInfo JSArrowFunction::s_info = { "Function", &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(JSArrowFunction) }; | 
 |  | 
 | bool JSFunction::isHostFunctionNonInline() const | 
 | { | 
 |     return isHostFunction(); | 
 | } | 
 |  | 
 | Structure* JSFunction::selectStructureForNewFuncExp(JSGlobalObject* globalObject, FunctionExecutable* executable) | 
 | { | 
 |     ASSERT(!executable->isHostFunction()); | 
 |     bool isBuiltin = executable->isBuiltinFunction(); | 
 |     if (executable->isArrowFunction()) | 
 |         return globalObject->arrowFunctionStructure(isBuiltin); | 
 |     if (executable->isInStrictContext()) | 
 |         return globalObject->strictFunctionStructure(isBuiltin); | 
 |     return globalObject->sloppyFunctionStructure(isBuiltin); | 
 | } | 
 |  | 
 | JSFunction* JSFunction::create(VM& vm, FunctionExecutable* executable, JSScope* scope) | 
 | { | 
 |     return create(vm, executable, scope, selectStructureForNewFuncExp(scope->globalObject(vm), executable)); | 
 | } | 
 |  | 
 | JSFunction* JSFunction::create(VM& vm, FunctionExecutable* executable, JSScope* scope, Structure* structure) | 
 | { | 
 |     JSFunction* result = createImpl(vm, executable, scope, structure); | 
 |     executable->notifyCreation(vm, result, "Allocating a function"); | 
 |     return result; | 
 | } | 
 |  | 
 | JSFunction* JSFunction::create(VM& vm, JSGlobalObject* globalObject, unsigned length, const String& name, NativeFunction nativeFunction, Intrinsic intrinsic, NativeFunction nativeConstructor, const DOMJIT::Signature* signature) | 
 | { | 
 |     NativeExecutable* executable = vm.getHostFunction(nativeFunction, intrinsic, nativeConstructor, signature, name); | 
 |     Structure* structure = globalObject->hostFunctionStructure(); | 
 |     JSFunction* function = new (NotNull, allocateCell<JSFunction>(vm.heap)) JSFunction(vm, executable, globalObject, structure); | 
 |     // Can't do this during initialization because getHostFunction might do a GC allocation. | 
 |     function->finishCreation(vm, executable, length, name); | 
 |     return function; | 
 | } | 
 |  | 
 | JSFunction::JSFunction(VM& vm, NativeExecutable* executable, JSGlobalObject* globalObject, Structure* structure) | 
 |     : Base(vm, globalObject, structure) | 
 |     , m_executableOrRareData(bitwise_cast<uintptr_t>(executable)) | 
 | { | 
 |     assertTypeInfoFlagInvariants(); | 
 |     ASSERT(structure->globalObject() == globalObject); | 
 | } | 
 |  | 
 |  | 
 | void JSFunction::finishCreation(VM& vm) | 
 | { | 
 |     Base::finishCreation(vm); | 
 |     ASSERT(jsDynamicCast<JSFunction*>(vm, this)); | 
 |     ASSERT(type() == JSFunctionType); | 
 |     // JSCell::{getCallData,getConstructData} relies on the following conditions. | 
 |     ASSERT(methodTable(vm)->getConstructData == &JSFunction::getConstructData); | 
 |     ASSERT(methodTable(vm)->getCallData == &JSFunction::getCallData); | 
 | } | 
 |  | 
 | void JSFunction::finishCreation(VM& vm, NativeExecutable*, unsigned length, const String& name) | 
 | { | 
 |     Base::finishCreation(vm); | 
 |     ASSERT(inherits(vm, info())); | 
 |     ASSERT(type() == JSFunctionType); | 
 |     // JSCell::{getCallData,getConstructData} relies on the following conditions. | 
 |     ASSERT(methodTable(vm)->getConstructData == &JSFunction::getConstructData); | 
 |     ASSERT(methodTable(vm)->getCallData == &JSFunction::getCallData); | 
 |  | 
 |     // JSBoundFunction instances use finishCreation(VM&) overload and lazily allocate their name string / length. | 
 |     ASSERT(!this->inherits<JSBoundFunction>(vm)); | 
 |  | 
 |     if (!name.isNull()) | 
 |         putDirect(vm, vm.propertyNames->name, jsString(vm, name), PropertyAttribute::ReadOnly | PropertyAttribute::DontEnum); | 
 |     putDirect(vm, vm.propertyNames->length, jsNumber(length), PropertyAttribute::ReadOnly | PropertyAttribute::DontEnum); | 
 | } | 
 |  | 
 | FunctionRareData* JSFunction::allocateRareData(VM& vm) | 
 | { | 
 |     uintptr_t executableOrRareData = m_executableOrRareData; | 
 |     ASSERT(!(executableOrRareData & rareDataTag)); | 
 |     FunctionRareData* rareData = FunctionRareData::create(vm, bitwise_cast<ExecutableBase*>(executableOrRareData)); | 
 |     executableOrRareData = bitwise_cast<uintptr_t>(rareData) | rareDataTag; | 
 |  | 
 |     // A DFG compilation thread may be trying to read the rare data | 
 |     // We want to ensure that it sees it properly allocated | 
 |     WTF::storeStoreFence(); | 
 |  | 
 |     m_executableOrRareData = executableOrRareData; | 
 |     vm.heap.writeBarrier(this, rareData); | 
 |  | 
 |     return rareData; | 
 | } | 
 |  | 
 | JSObject* JSFunction::prototypeForConstruction(VM& vm, JSGlobalObject* globalObject) | 
 | { | 
 |     // This code assumes getting the prototype is not effectful. That's only | 
 |     // true when we can use the allocation profile. | 
 |     ASSERT(canUseAllocationProfile());  | 
 |     auto scope = DECLARE_CATCH_SCOPE(vm); | 
 |     JSValue prototype = get(globalObject, vm.propertyNames->prototype); | 
 |     scope.releaseAssertNoException(); | 
 |     if (LIKELY(prototype.isObject())) | 
 |         return asObject(prototype); | 
 |     if (isHostOrBuiltinFunction()) | 
 |         return this->globalObject()->objectPrototype(); | 
 |  | 
 |     JSGlobalObject* scopeGlobalObject = this->scope()->globalObject(); | 
 |     // https://tc39.github.io/ecma262/#sec-generator-function-definitions-runtime-semantics-evaluatebody | 
 |     if (isGeneratorWrapperParseMode(jsExecutable()->parseMode())) | 
 |         return scopeGlobalObject->generatorPrototype(); | 
 |     // https://tc39.github.io/ecma262/#sec-asyncgenerator-definitions-evaluatebody | 
 |     if (isAsyncGeneratorWrapperParseMode(jsExecutable()->parseMode())) | 
 |         return scopeGlobalObject->asyncGeneratorPrototype(); | 
 |     return scopeGlobalObject->objectPrototype(); | 
 | } | 
 |  | 
 | FunctionRareData* JSFunction::allocateAndInitializeRareData(JSGlobalObject* globalObject, size_t inlineCapacity) | 
 | { | 
 |     uintptr_t executableOrRareData = m_executableOrRareData; | 
 |     ASSERT(!(executableOrRareData & rareDataTag)); | 
 |     ASSERT(canUseAllocationProfile()); | 
 |     VM& vm = globalObject->vm(); | 
 |     JSObject* prototype = prototypeForConstruction(vm, globalObject); | 
 |     FunctionRareData* rareData = FunctionRareData::create(vm, bitwise_cast<ExecutableBase*>(executableOrRareData)); | 
 |     rareData->initializeObjectAllocationProfile(vm, this->globalObject(), prototype, inlineCapacity, this); | 
 |     executableOrRareData = bitwise_cast<uintptr_t>(rareData) | rareDataTag; | 
 |  | 
 |     // A DFG compilation thread may be trying to read the rare data | 
 |     // We want to ensure that it sees it properly allocated | 
 |     WTF::storeStoreFence(); | 
 |  | 
 |     m_executableOrRareData = executableOrRareData; | 
 |     vm.heap.writeBarrier(this, rareData); | 
 |  | 
 |     return rareData; | 
 | } | 
 |  | 
 | FunctionRareData* JSFunction::initializeRareData(JSGlobalObject* globalObject, size_t inlineCapacity) | 
 | { | 
 |     uintptr_t executableOrRareData = m_executableOrRareData; | 
 |     ASSERT(executableOrRareData & rareDataTag); | 
 |     ASSERT(canUseAllocationProfile()); | 
 |     VM& vm = globalObject->vm(); | 
 |     JSObject* prototype = prototypeForConstruction(vm, globalObject); | 
 |     FunctionRareData* rareData = bitwise_cast<FunctionRareData*>(executableOrRareData & ~rareDataTag); | 
 |     rareData->initializeObjectAllocationProfile(vm, this->globalObject(), prototype, inlineCapacity, this); | 
 |     return rareData; | 
 | } | 
 |  | 
 | String JSFunction::name(VM& vm) | 
 | { | 
 |     if (isHostFunction()) { | 
 |         if (this->inherits<JSBoundFunction>(vm)) | 
 |             return jsCast<JSBoundFunction*>(this)->nameString(); | 
 |         NativeExecutable* executable = jsCast<NativeExecutable*>(this->executable()); | 
 |         return executable->name(); | 
 |     } | 
 |     const Identifier identifier = jsExecutable()->name(); | 
 |     if (identifier == vm.propertyNames->starDefaultPrivateName) | 
 |         return emptyString(); | 
 |     return identifier.string(); | 
 | } | 
 |  | 
 | String JSFunction::displayName(VM& vm) | 
 | { | 
 |     JSValue displayName = getDirect(vm, vm.propertyNames->displayName); | 
 |      | 
 |     if (displayName && isJSString(displayName)) | 
 |         return asString(displayName)->tryGetValue(); | 
 |      | 
 |     return String(); | 
 | } | 
 |  | 
 | const String JSFunction::calculatedDisplayName(VM& vm) | 
 | { | 
 |     const String explicitName = displayName(vm); | 
 |      | 
 |     if (!explicitName.isEmpty()) | 
 |         return explicitName; | 
 |      | 
 |     const String actualName = name(vm); | 
 |     if (!actualName.isEmpty() || isHostOrBuiltinFunction()) | 
 |         return actualName; | 
 |  | 
 |     return jsExecutable()->ecmaName().string(); | 
 | } | 
 |  | 
 | const SourceCode* JSFunction::sourceCode() const | 
 | { | 
 |     if (isHostOrBuiltinFunction()) | 
 |         return nullptr; | 
 |     return &jsExecutable()->source(); | 
 | } | 
 |      | 
 | void JSFunction::visitChildren(JSCell* cell, SlotVisitor& visitor) | 
 | { | 
 |     JSFunction* thisObject = jsCast<JSFunction*>(cell); | 
 |     ASSERT_GC_OBJECT_INHERITS(thisObject, info()); | 
 |     Base::visitChildren(thisObject, visitor); | 
 |  | 
 |     visitor.appendUnbarriered(bitwise_cast<JSCell*>(bitwise_cast<uintptr_t>(thisObject->m_executableOrRareData) & ~rareDataTag)); | 
 | } | 
 |  | 
 | CallData JSFunction::getCallData(JSCell* cell) | 
 | { | 
 |     // Keep this function OK for invocation from concurrent compilers. | 
 |     CallData callData; | 
 |  | 
 |     JSFunction* thisObject = jsCast<JSFunction*>(cell); | 
 |     if (thisObject->isHostFunction()) { | 
 |         callData.type = CallData::Type::Native; | 
 |         callData.native.function = thisObject->nativeFunction(); | 
 |     } else { | 
 |         callData.type = CallData::Type::JS; | 
 |         callData.js.functionExecutable = thisObject->jsExecutable(); | 
 |         callData.js.scope = thisObject->scope(); | 
 |     } | 
 |  | 
 |     return callData; | 
 | } | 
 |  | 
 | class RetrieveArgumentsFunctor { | 
 | public: | 
 |     RetrieveArgumentsFunctor(VM& vm, JSFunction* functionObj) | 
 |         : m_vm(vm) | 
 |         , m_targetCallee(functionObj) | 
 |         , m_result(jsNull()) | 
 |     { | 
 |     } | 
 |  | 
 |     JSValue result() const { return m_result; } | 
 |  | 
 |     StackVisitor::Status operator()(StackVisitor& visitor) const | 
 |     { | 
 |         if (!visitor->callee().isCell()) | 
 |             return StackVisitor::Continue; | 
 |  | 
 |         JSCell* callee = visitor->callee().asCell(); | 
 |         if (callee != m_targetCallee) | 
 |             return StackVisitor::Continue; | 
 |  | 
 |         m_result = JSValue(visitor->createArguments(m_vm)); | 
 |         return StackVisitor::Done; | 
 |     } | 
 |  | 
 | private: | 
 |     VM& m_vm; | 
 |     JSObject* m_targetCallee; | 
 |     mutable JSValue m_result; | 
 | }; | 
 |  | 
 | static JSValue retrieveArguments(VM& vm, CallFrame* callFrame, JSFunction* functionObj) | 
 | { | 
 |     RetrieveArgumentsFunctor functor(vm, functionObj); | 
 |     if (callFrame) | 
 |         callFrame->iterate(vm, functor); | 
 |     return functor.result(); | 
 | } | 
 |  | 
 | JSC_DEFINE_CUSTOM_GETTER(argumentsGetter, (JSGlobalObject* globalObject, EncodedJSValue thisValue, PropertyName)) | 
 | { | 
 |     VM& vm = globalObject->vm(); | 
 |     JSFunction* thisObj = jsCast<JSFunction*>(JSValue::decode(thisValue)); | 
 |     ASSERT(!thisObj->isHostFunction()); | 
 |  | 
 |     return JSValue::encode(retrieveArguments(vm, vm.topCallFrame, thisObj)); | 
 | } | 
 |  | 
 | class RetrieveCallerFunctionFunctor { | 
 | public: | 
 |     RetrieveCallerFunctionFunctor(JSFunction* functionObj) | 
 |         : m_targetCallee(functionObj) | 
 |         , m_hasFoundFrame(false) | 
 |         , m_hasSkippedToCallerFrame(false) | 
 |         , m_result(jsNull()) | 
 |     { | 
 |     } | 
 |  | 
 |     JSValue result() const { return m_result; } | 
 |  | 
 |     StackVisitor::Status operator()(StackVisitor& visitor) const | 
 |     { | 
 |         if (!visitor->callee().isCell()) | 
 |             return StackVisitor::Continue; | 
 |  | 
 |         JSCell* callee = visitor->callee().asCell(); | 
 |  | 
 |         if (callee && callee->inherits<JSBoundFunction>(callee->vm())) | 
 |             return StackVisitor::Continue; | 
 |  | 
 |         if (!m_hasFoundFrame && (callee != m_targetCallee)) | 
 |             return StackVisitor::Continue; | 
 |  | 
 |         m_hasFoundFrame = true; | 
 |         if (!m_hasSkippedToCallerFrame) { | 
 |             m_hasSkippedToCallerFrame = true; | 
 |             return StackVisitor::Continue; | 
 |         } | 
 |  | 
 |         if (callee) | 
 |             m_result = callee; | 
 |         return StackVisitor::Done; | 
 |     } | 
 |  | 
 | private: | 
 |     JSObject* m_targetCallee; | 
 |     mutable bool m_hasFoundFrame; | 
 |     mutable bool m_hasSkippedToCallerFrame; | 
 |     mutable JSValue m_result; | 
 | }; | 
 |  | 
 | static JSValue retrieveCallerFunction(VM& vm, CallFrame* callFrame, JSFunction* functionObj) | 
 | { | 
 |     RetrieveCallerFunctionFunctor functor(functionObj); | 
 |     if (callFrame) | 
 |         callFrame->iterate(vm, functor); | 
 |     return functor.result(); | 
 | } | 
 |  | 
 | JSC_DEFINE_CUSTOM_GETTER(callerGetter, (JSGlobalObject* globalObject, EncodedJSValue thisValue, PropertyName)) | 
 | { | 
 |     VM& vm = globalObject->vm(); | 
 |  | 
 |     JSFunction* thisObj = jsCast<JSFunction*>(JSValue::decode(thisValue)); | 
 |     ASSERT(!thisObj->isHostFunction()); | 
 |     JSValue caller = retrieveCallerFunction(vm, vm.topCallFrame, 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>(vm)) { | 
 |         // It isn't a JSFunction, but if it is a JSCallee from a program or eval call or an internal constructor, return null. | 
 |         if (jsDynamicCast<JSCallee*>(vm, caller) || jsDynamicCast<InternalFunction*>(vm, caller)) | 
 |             return JSValue::encode(jsNull()); | 
 |         return JSValue::encode(caller); | 
 |     } | 
 |     JSFunction* function = jsCast<JSFunction*>(caller); | 
 |  | 
 |     // Firefox returns null for native code callers, so we match that behavior. | 
 |     if (function->isHostOrBuiltinFunction()) | 
 |         return JSValue::encode(jsNull()); | 
 |  | 
 |     if (!function->jsExecutable()->hasCallerAndArgumentsProperties()) | 
 |         return JSValue::encode(jsNull()); | 
 |  | 
 |     return JSValue::encode(caller); | 
 | } | 
 |  | 
 | bool JSFunction::getOwnPropertySlot(JSObject* object, JSGlobalObject* globalObject, PropertyName propertyName, PropertySlot& slot) | 
 | { | 
 |     VM& vm = globalObject->vm(); | 
 |     auto scope = DECLARE_THROW_SCOPE(vm); | 
 |  | 
 |     JSFunction* thisObject = jsCast<JSFunction*>(object); | 
 |     if (thisObject->isHostOrBuiltinFunction()) { | 
 |         thisObject->reifyLazyPropertyForHostOrBuiltinIfNeeded(vm, globalObject, propertyName); | 
 |         RETURN_IF_EXCEPTION(scope, false); | 
 |         RELEASE_AND_RETURN(scope, Base::getOwnPropertySlot(thisObject, globalObject, propertyName, slot)); | 
 |     } | 
 |  | 
 |     if (propertyName == vm.propertyNames->prototype && thisObject->jsExecutable()->hasPrototypeProperty() && !thisObject->jsExecutable()->isClassConstructorFunction()) { | 
 |         // NOTE: class constructors define the prototype property in bytecode using | 
 |         // defineOwnProperty, which ends up calling into this code (see our defineOwnProperty | 
 |         // implementation below). The bytecode will end up doing the proper definition | 
 |         // with the property being non-writable/non-configurable. However, we must ignore | 
 |         // the initial materialization of the property so that the defineOwnProperty call | 
 |         // from bytecode succeeds. Otherwise, the materialization here would prevent the | 
 |         // defineOwnProperty from being able to overwrite the property. | 
 |         unsigned attributes; | 
 |         PropertyOffset offset = thisObject->getDirectOffset(vm, propertyName, attributes); | 
 |         if (!isValidOffset(offset)) { | 
 |             JSGlobalObject* scopeGlobalObject = thisObject->scope()->globalObject(); | 
 |             JSObject* prototype = nullptr; | 
 |             if (isGeneratorWrapperParseMode(thisObject->jsExecutable()->parseMode())) { | 
 |                 // Unlike function instances, the object that is the value of the a GeneratorFunction's prototype | 
 |                 // property does not have a constructor property whose value is the GeneratorFunction instance. | 
 |                 // https://tc39.github.io/ecma262/#sec-generatorfunction-instances-prototype | 
 |                 prototype = constructEmptyObject(globalObject, scopeGlobalObject->generatorPrototype()); | 
 |             } else if (isAsyncGeneratorWrapperParseMode(thisObject->jsExecutable()->parseMode())) | 
 |                 prototype = constructEmptyObject(globalObject, scopeGlobalObject->asyncGeneratorPrototype()); | 
 |             else { | 
 |                 prototype = constructEmptyObject(globalObject, scopeGlobalObject->objectPrototype()); | 
 |                 prototype->putDirect(vm, vm.propertyNames->constructor, thisObject, static_cast<unsigned>(PropertyAttribute::DontEnum)); | 
 |             } | 
 |  | 
 |             thisObject->putDirect(vm, vm.propertyNames->prototype, prototype, PropertyAttribute::DontDelete | PropertyAttribute::DontEnum); | 
 |             offset = thisObject->getDirectOffset(vm, vm.propertyNames->prototype, attributes); | 
 |             ASSERT(isValidOffset(offset)); | 
 |         } | 
 |         slot.setValue(thisObject, attributes, thisObject->getDirect(offset), offset); | 
 |     } | 
 |  | 
 |     if (propertyName == vm.propertyNames->arguments) { | 
 |         if (!thisObject->jsExecutable()->hasCallerAndArgumentsProperties()) | 
 |             RELEASE_AND_RETURN(scope, Base::getOwnPropertySlot(thisObject, globalObject, propertyName, slot)); | 
 |          | 
 |         slot.setCacheableCustom(thisObject, PropertyAttribute::ReadOnly | PropertyAttribute::DontEnum | PropertyAttribute::DontDelete, argumentsGetter); | 
 |         return true; | 
 |  | 
 |     } else if (propertyName == vm.propertyNames->caller) { | 
 |         if (!thisObject->jsExecutable()->hasCallerAndArgumentsProperties()) | 
 |             RELEASE_AND_RETURN(scope, Base::getOwnPropertySlot(thisObject, globalObject, propertyName, slot)); | 
 |  | 
 |         slot.setCacheableCustom(thisObject, PropertyAttribute::ReadOnly | PropertyAttribute::DontEnum | PropertyAttribute::DontDelete, callerGetter); | 
 |         return true; | 
 |     } | 
 |  | 
 |     thisObject->reifyLazyPropertyIfNeeded(vm, globalObject, propertyName); | 
 |     RETURN_IF_EXCEPTION(scope, false); | 
 |  | 
 |     RELEASE_AND_RETURN(scope, Base::getOwnPropertySlot(thisObject, globalObject, propertyName, slot)); | 
 | } | 
 |  | 
 | void JSFunction::getOwnSpecialPropertyNames(JSObject* object, JSGlobalObject* globalObject, PropertyNameArray& propertyNames, DontEnumPropertiesMode mode) | 
 | { | 
 |     JSFunction* thisObject = jsCast<JSFunction*>(object); | 
 |     VM& vm = globalObject->vm(); | 
 |     auto scope = DECLARE_THROW_SCOPE(vm); | 
 |  | 
 |     if (mode == DontEnumPropertiesMode::Include) { | 
 |         if (!thisObject->isHostOrBuiltinFunction()) { | 
 |             // Make sure prototype has been reified. | 
 |             PropertySlot slot(thisObject, PropertySlot::InternalMethodType::VMInquiry, &vm); | 
 |             thisObject->methodTable(vm)->getOwnPropertySlot(thisObject, globalObject, vm.propertyNames->prototype, slot); | 
 |             RETURN_IF_EXCEPTION(scope, void()); | 
 |  | 
 |             if (thisObject->jsExecutable()->hasCallerAndArgumentsProperties()) { | 
 |                 propertyNames.add(vm.propertyNames->arguments); | 
 |                 propertyNames.add(vm.propertyNames->caller); | 
 |             } | 
 |             if (!thisObject->hasReifiedLength()) | 
 |                 propertyNames.add(vm.propertyNames->length); | 
 |             if (!thisObject->hasReifiedName()) | 
 |                 propertyNames.add(vm.propertyNames->name); | 
 |         } else { | 
 |             if (thisObject->isBuiltinFunction() || thisObject->inherits<JSBoundFunction>(vm)) { | 
 |                 if (!thisObject->hasReifiedLength()) | 
 |                     propertyNames.add(vm.propertyNames->length); | 
 |                 if (!thisObject->hasReifiedName()) | 
 |                     propertyNames.add(vm.propertyNames->name); | 
 |             } | 
 |         } | 
 |     } | 
 | } | 
 |  | 
 | bool JSFunction::put(JSCell* cell, JSGlobalObject* globalObject, PropertyName propertyName, JSValue value, PutPropertySlot& slot) | 
 | { | 
 |     VM& vm = globalObject->vm(); | 
 |     auto scope = DECLARE_THROW_SCOPE(vm); | 
 |  | 
 |     JSFunction* thisObject = jsCast<JSFunction*>(cell); | 
 |  | 
 |     if (propertyName == vm.propertyNames->length || propertyName == vm.propertyNames->name) { | 
 |         FunctionRareData* rareData = thisObject->ensureRareData(vm); | 
 |         if (propertyName == vm.propertyNames->length) | 
 |             rareData->setHasModifiedLengthForNonHostFunction(); | 
 |         else | 
 |             rareData->setHasModifiedNameForNonHostFunction(); | 
 |     } | 
 |  | 
 |     if (UNLIKELY(isThisValueAltered(slot, thisObject))) | 
 |         RELEASE_AND_RETURN(scope, ordinarySetSlow(globalObject, thisObject, propertyName, value, slot.thisValue(), slot.isStrictMode())); | 
 |  | 
 |  | 
 |     if (thisObject->isHostOrBuiltinFunction()) { | 
 |         PropertyStatus propertyType = thisObject->reifyLazyPropertyForHostOrBuiltinIfNeeded(vm, globalObject, propertyName); | 
 |         RETURN_IF_EXCEPTION(scope, false); | 
 |         if (isLazy(propertyType)) | 
 |             slot.disableCaching(); | 
 |         RELEASE_AND_RETURN(scope, Base::put(thisObject, globalObject, propertyName, value, slot)); | 
 |     } | 
 |  | 
 |     if (propertyName == vm.propertyNames->prototype) { | 
 |         slot.disableCaching(); | 
 |         // 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 getSlot(thisObject, PropertySlot::InternalMethodType::VMInquiry, &vm); | 
 |         thisObject->methodTable(vm)->getOwnPropertySlot(thisObject, globalObject, propertyName, getSlot); | 
 |         RETURN_IF_EXCEPTION(scope, false); | 
 |         if (FunctionRareData* rareData = thisObject->rareData()) | 
 |             rareData->clear("Store to prototype property of a function"); | 
 |         getSlot.disallowVMEntry.reset(); | 
 |         RELEASE_AND_RETURN(scope, Base::put(thisObject, globalObject, propertyName, value, slot)); | 
 |     } | 
 |  | 
 |     if (propertyName == vm.propertyNames->arguments || propertyName == vm.propertyNames->caller) { | 
 |         if (!thisObject->jsExecutable()->hasCallerAndArgumentsProperties()) | 
 |             RELEASE_AND_RETURN(scope, Base::put(thisObject, globalObject, propertyName, value, slot)); | 
 |  | 
 |         slot.disableCaching(); | 
 |         return typeError(globalObject, scope, slot.isStrictMode(), ReadonlyPropertyWriteError); | 
 |     } | 
 |     PropertyStatus propertyType = thisObject->reifyLazyPropertyIfNeeded(vm, globalObject, propertyName); | 
 |     if (isLazy(propertyType)) | 
 |         slot.disableCaching(); | 
 |     RELEASE_AND_RETURN(scope, Base::put(thisObject, globalObject, propertyName, value, slot)); | 
 | } | 
 |  | 
 | bool JSFunction::deleteProperty(JSCell* cell, JSGlobalObject* globalObject, PropertyName propertyName, DeletePropertySlot& slot) | 
 | { | 
 |     VM& vm = globalObject->vm(); | 
 |     auto scope = DECLARE_THROW_SCOPE(vm); | 
 |     JSFunction* thisObject = jsCast<JSFunction*>(cell); | 
 |  | 
 |     if (propertyName == vm.propertyNames->length || propertyName == vm.propertyNames->name) { | 
 |         FunctionRareData* rareData = thisObject->ensureRareData(vm); | 
 |         if (propertyName == vm.propertyNames->length) | 
 |             rareData->setHasModifiedLengthForNonHostFunction(); | 
 |         else | 
 |             rareData->setHasModifiedNameForNonHostFunction(); | 
 |     } | 
 |  | 
 |     if (thisObject->isHostOrBuiltinFunction()) { | 
 |         thisObject->reifyLazyPropertyForHostOrBuiltinIfNeeded(vm, globalObject, propertyName); | 
 |         RETURN_IF_EXCEPTION(scope, false); | 
 |     } else if (vm.deletePropertyMode() != VM::DeletePropertyMode::IgnoreConfigurable) { | 
 |         // For non-host functions, don't let these properties by deleted - except by DefineOwnProperty. | 
 |         FunctionExecutable* executable = thisObject->jsExecutable(); | 
 |          | 
 |         if ((propertyName == vm.propertyNames->caller || propertyName == vm.propertyNames->arguments) && executable->hasCallerAndArgumentsProperties()) | 
 |             return false; | 
 |  | 
 |         if (propertyName == vm.propertyNames->prototype && executable->hasPrototypeProperty()) | 
 |             return false; | 
 |  | 
 |         thisObject->reifyLazyPropertyIfNeeded(vm, globalObject, propertyName); | 
 |         RETURN_IF_EXCEPTION(scope, false); | 
 |     } | 
 |      | 
 |     RELEASE_AND_RETURN(scope, Base::deleteProperty(thisObject, globalObject, propertyName, slot)); | 
 | } | 
 |  | 
 | bool JSFunction::defineOwnProperty(JSObject* object, JSGlobalObject* globalObject, PropertyName propertyName, const PropertyDescriptor& descriptor, bool throwException) | 
 | { | 
 |     VM& vm = globalObject->vm(); | 
 |     auto scope = DECLARE_THROW_SCOPE(vm); | 
 |  | 
 |     JSFunction* thisObject = jsCast<JSFunction*>(object); | 
 |  | 
 |     if (propertyName == vm.propertyNames->length || propertyName == vm.propertyNames->name) { | 
 |         FunctionRareData* rareData = thisObject->ensureRareData(vm); | 
 |         if (propertyName == vm.propertyNames->length) | 
 |             rareData->setHasModifiedLengthForNonHostFunction(); | 
 |         else | 
 |             rareData->setHasModifiedNameForNonHostFunction(); | 
 |     } | 
 |  | 
 |     if (thisObject->isHostOrBuiltinFunction()) { | 
 |         thisObject->reifyLazyPropertyForHostOrBuiltinIfNeeded(vm, globalObject, propertyName); | 
 |         RETURN_IF_EXCEPTION(scope, false); | 
 |         RELEASE_AND_RETURN(scope, Base::defineOwnProperty(object, globalObject, propertyName, descriptor, throwException)); | 
 |     } | 
 |  | 
 |     if (propertyName == vm.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, PropertySlot::InternalMethodType::VMInquiry, &vm); | 
 |         thisObject->methodTable(vm)->getOwnPropertySlot(thisObject, globalObject, propertyName, slot); | 
 |         RETURN_IF_EXCEPTION(scope, false); | 
 |         if (FunctionRareData* rareData = thisObject->rareData()) | 
 |             rareData->clear("Store to prototype property of a function"); | 
 |         slot.disallowVMEntry.reset(); | 
 |         RELEASE_AND_RETURN(scope, Base::defineOwnProperty(object, globalObject, propertyName, descriptor, throwException)); | 
 |     } | 
 |  | 
 |     bool valueCheck; | 
 |     if (propertyName == vm.propertyNames->arguments) { | 
 |         if (!thisObject->jsExecutable()->hasCallerAndArgumentsProperties()) | 
 |             RELEASE_AND_RETURN(scope, Base::defineOwnProperty(object, globalObject, propertyName, descriptor, throwException)); | 
 |  | 
 |         valueCheck = !descriptor.value(); | 
 |         if (!valueCheck) { | 
 |             valueCheck = sameValue(globalObject, descriptor.value(), retrieveArguments(vm, vm.topCallFrame, thisObject)); | 
 |             RETURN_IF_EXCEPTION(scope, false); | 
 |         } | 
 |     } else if (propertyName == vm.propertyNames->caller) { | 
 |         if (!thisObject->jsExecutable()->hasCallerAndArgumentsProperties()) | 
 |             RELEASE_AND_RETURN(scope, Base::defineOwnProperty(object, globalObject, propertyName, descriptor, throwException)); | 
 |  | 
 |         valueCheck = !descriptor.value(); | 
 |         if (!valueCheck) { | 
 |             valueCheck = sameValue(globalObject, descriptor.value(), retrieveCallerFunction(vm, vm.topCallFrame, thisObject)); | 
 |             RETURN_IF_EXCEPTION(scope, false); | 
 |         } | 
 |     } else { | 
 |         thisObject->reifyLazyPropertyIfNeeded(vm, globalObject, propertyName); | 
 |         RETURN_IF_EXCEPTION(scope, false); | 
 |         RELEASE_AND_RETURN(scope, Base::defineOwnProperty(object, globalObject, propertyName, descriptor, throwException)); | 
 |     } | 
 |       | 
 |     if (descriptor.configurablePresent() && descriptor.configurable()) | 
 |         return typeError(globalObject, scope, throwException, UnconfigurablePropertyChangeConfigurabilityError); | 
 |     if (descriptor.enumerablePresent() && descriptor.enumerable()) | 
 |         return typeError(globalObject, scope, throwException, UnconfigurablePropertyChangeEnumerabilityError); | 
 |     if (descriptor.isAccessorDescriptor()) | 
 |         return typeError(globalObject, scope, throwException, UnconfigurablePropertyChangeAccessMechanismError); | 
 |     if (descriptor.writablePresent() && descriptor.writable()) | 
 |         return typeError(globalObject, scope, throwException, UnconfigurablePropertyChangeWritabilityError); | 
 |     if (!valueCheck) | 
 |         return typeError(globalObject, scope, throwException, ReadonlyPropertyChangeError); | 
 |     return true; | 
 | } | 
 |  | 
 | // ECMA 13.2.2 [[Construct]] | 
 | CallData JSFunction::getConstructData(JSCell* cell) | 
 | { | 
 |     // Keep this function OK for invocation from concurrent compilers. | 
 |     CallData constructData; | 
 |  | 
 |     JSFunction* thisObject = jsCast<JSFunction*>(cell); | 
 |     if (thisObject->isHostFunction()) { | 
 |         if (thisObject->nativeConstructor() != callHostFunctionAsConstructor) { | 
 |             constructData.type = CallData::Type::Native; | 
 |             constructData.native.function = thisObject->nativeConstructor(); | 
 |         } | 
 |     } else { | 
 |         FunctionExecutable* functionExecutable = thisObject->jsExecutable(); | 
 |         if (functionExecutable->constructAbility() != ConstructAbility::CannotConstruct) { | 
 |             constructData.type = CallData::Type::JS; | 
 |             constructData.js.functionExecutable = functionExecutable; | 
 |             constructData.js.scope = thisObject->scope(); | 
 |         } | 
 |     } | 
 |  | 
 |     return constructData; | 
 | } | 
 |  | 
 | String getCalculatedDisplayName(VM& vm, JSObject* object) | 
 | { | 
 | #if ENABLE(WEBASSEMBLY) | 
 |     if (jsDynamicCast<JSToWasmICCallee*>(vm, object)) | 
 |         return "wasm-stub"_s; | 
 | #endif | 
 |  | 
 |     if (!jsDynamicCast<JSFunction*>(vm, object) && !jsDynamicCast<InternalFunction*>(vm, object)) | 
 |         return emptyString(); | 
 |  | 
 |     Structure* structure = object->structure(vm); | 
 |     unsigned attributes; | 
 |     // This function may be called when the mutator isn't running and we are lazily generating a stack trace. | 
 |     PropertyOffset offset = structure->getConcurrently(vm.propertyNames->displayName.impl(), attributes); | 
 |     if (offset != invalidOffset && !(attributes & (PropertyAttribute::Accessor | PropertyAttribute::CustomAccessorOrValue))) { | 
 |         JSValue displayName = object->getDirect(offset); | 
 |         if (displayName && displayName.isString()) | 
 |             return asString(displayName)->tryGetValue(); | 
 |     } | 
 |  | 
 |     if (auto* function = jsDynamicCast<JSFunction*>(vm, object)) { | 
 |         const String actualName = function->name(vm); | 
 |         if (!actualName.isEmpty() || function->isHostOrBuiltinFunction()) | 
 |             return actualName; | 
 |  | 
 |         return function->jsExecutable()->ecmaName().string(); | 
 |     } | 
 |     if (auto* function = jsDynamicCast<InternalFunction*>(vm, object)) | 
 |         return function->name(); | 
 |  | 
 |  | 
 |     return emptyString(); | 
 | } | 
 |  | 
 | void JSFunction::setFunctionName(JSGlobalObject* globalObject, JSValue value) | 
 | { | 
 |     VM& vm = globalObject->vm(); | 
 |     auto scope = DECLARE_THROW_SCOPE(vm); | 
 |  | 
 |     // The "name" property may have been already been defined as part of a property list in an | 
 |     // object literal (and therefore reified). | 
 |     if (hasReifiedName()) | 
 |         return; | 
 |  | 
 |     ASSERT(!isHostFunction()); | 
 |     ASSERT(jsExecutable()->ecmaName().isNull()); | 
 |     String name; | 
 |     if (value.isSymbol()) { | 
 |         PrivateName privateName = asSymbol(value)->privateName(); | 
 |         SymbolImpl& uid = privateName.uid(); | 
 |         if (uid.isNullSymbol()) | 
 |             name = emptyString(); | 
 |         else | 
 |             name = makeString('[', String(&uid), ']'); | 
 |     } else { | 
 |         ASSERT(value.isString()); | 
 |         name = asString(value)->value(globalObject); | 
 |         RETURN_IF_EXCEPTION(scope, void()); | 
 |     } | 
 |     reifyName(vm, globalObject, name); | 
 | } | 
 |  | 
 | void JSFunction::reifyLength(VM& vm) | 
 | { | 
 |     FunctionRareData* rareData = this->ensureRareData(vm); | 
 |  | 
 |     ASSERT(!hasReifiedLength()); | 
 |     double length = 0; | 
 |     if (this->inherits<JSBoundFunction>(vm)) | 
 |         length = jsCast<JSBoundFunction*>(this)->length(vm); | 
 |     else { | 
 |         ASSERT(!isHostFunction()); | 
 |         length = jsExecutable()->parameterCount(); | 
 |     } | 
 |     JSValue initialValue = jsNumber(length); | 
 |     unsigned initialAttributes = PropertyAttribute::DontEnum | PropertyAttribute::ReadOnly; | 
 |     const Identifier& identifier = vm.propertyNames->length; | 
 |     rareData->setHasReifiedLength(); | 
 |     putDirect(vm, identifier, initialValue, initialAttributes); | 
 | } | 
 |  | 
 | void JSFunction::reifyName(VM& vm, JSGlobalObject* globalObject) | 
 | { | 
 |     const Identifier& ecmaName = jsExecutable()->ecmaName(); | 
 |     String name; | 
 |     // https://tc39.github.io/ecma262/#sec-exports-runtime-semantics-evaluation | 
 |     // When the ident is "*default*", we need to set "default" for the ecma name. | 
 |     // This "*default*" name is never shown to users. | 
 |     if (ecmaName == vm.propertyNames->starDefaultPrivateName) | 
 |         name = vm.propertyNames->defaultKeyword.string(); | 
 |     else | 
 |         name = ecmaName.string(); | 
 |     reifyName(vm, globalObject, name); | 
 | } | 
 |  | 
 | void JSFunction::reifyName(VM& vm, JSGlobalObject* globalObject, String name) | 
 | { | 
 |     FunctionRareData* rareData = this->ensureRareData(vm); | 
 |  | 
 |     ASSERT(!hasReifiedName()); | 
 |     ASSERT(!isHostFunction()); | 
 |     unsigned initialAttributes = PropertyAttribute::DontEnum | PropertyAttribute::ReadOnly; | 
 |     const Identifier& propID = vm.propertyNames->name; | 
 |  | 
 |     if (globalObject->needsSiteSpecificQuirks()) { | 
 |         auto illegalCharMatcher = [] (UChar ch) -> bool { | 
 |             return ch == ' ' || ch == '|'; | 
 |         }; | 
 |         if (name.find(illegalCharMatcher) != notFound) | 
 |             name = String(); | 
 |     } | 
 |      | 
 |     if (jsExecutable()->isGetter()) | 
 |         name = makeString("get ", name); | 
 |     else if (jsExecutable()->isSetter()) | 
 |         name = makeString("set ", name); | 
 |  | 
 |     rareData->setHasReifiedName(); | 
 |     putDirect(vm, propID, jsString(vm, name), initialAttributes); | 
 | } | 
 |  | 
 | JSFunction::PropertyStatus JSFunction::reifyLazyPropertyIfNeeded(VM& vm, JSGlobalObject* globalObject, PropertyName propertyName) | 
 | { | 
 |     if (isHostOrBuiltinFunction() && !this->inherits<JSBoundFunction>(vm)) | 
 |         return PropertyStatus::Eager; | 
 |     PropertyStatus lazyLength = reifyLazyLengthIfNeeded(vm, globalObject, propertyName); | 
 |     if (isLazy(lazyLength)) | 
 |         return lazyLength; | 
 |     PropertyStatus lazyName = reifyLazyNameIfNeeded(vm, globalObject, propertyName); | 
 |     if (isLazy(lazyName)) | 
 |         return lazyName; | 
 |     return PropertyStatus::Eager; | 
 | } | 
 |  | 
 | JSFunction::PropertyStatus JSFunction::reifyLazyPropertyForHostOrBuiltinIfNeeded(VM& vm, JSGlobalObject* globalObject, PropertyName propertyName) | 
 | { | 
 |     ASSERT(isHostOrBuiltinFunction()); | 
 |     if (isBuiltinFunction() || this->inherits<JSBoundFunction>(vm)) { | 
 |         PropertyStatus lazyLength = reifyLazyLengthIfNeeded(vm, globalObject, propertyName); | 
 |         if (isLazy(lazyLength)) | 
 |             return lazyLength; | 
 |     } | 
 |     return reifyLazyBoundNameIfNeeded(vm, globalObject, propertyName); | 
 | } | 
 |  | 
 | JSFunction::PropertyStatus JSFunction::reifyLazyLengthIfNeeded(VM& vm, JSGlobalObject*, PropertyName propertyName) | 
 | { | 
 |     if (propertyName == vm.propertyNames->length) { | 
 |         if (!hasReifiedLength()) { | 
 |             reifyLength(vm); | 
 |             return PropertyStatus::Reified; | 
 |         } | 
 |         return PropertyStatus::Lazy; | 
 |     } | 
 |     return PropertyStatus::Eager; | 
 | } | 
 |  | 
 | JSFunction::PropertyStatus JSFunction::reifyLazyNameIfNeeded(VM& vm, JSGlobalObject* globalObject, PropertyName propertyName) | 
 | { | 
 |     if (propertyName == vm.propertyNames->name) { | 
 |         if (!hasReifiedName()) { | 
 |             reifyName(vm, globalObject); | 
 |             return PropertyStatus::Reified; | 
 |         } | 
 |         return PropertyStatus::Lazy; | 
 |     } | 
 |     return PropertyStatus::Eager; | 
 | } | 
 |  | 
 | JSFunction::PropertyStatus JSFunction::reifyLazyBoundNameIfNeeded(VM& vm, JSGlobalObject* globalObject, PropertyName propertyName) | 
 | { | 
 |     auto scope = DECLARE_THROW_SCOPE(vm); | 
 |  | 
 |     const Identifier& nameIdent = vm.propertyNames->name; | 
 |     if (propertyName != nameIdent) | 
 |         return PropertyStatus::Eager; | 
 |  | 
 |     if (hasReifiedName()) | 
 |         return PropertyStatus::Lazy; | 
 |  | 
 |     if (isBuiltinFunction()) | 
 |         reifyName(vm, globalObject); | 
 |     else if (this->inherits<JSBoundFunction>(vm)) { | 
 |         FunctionRareData* rareData = this->ensureRareData(vm); | 
 |         JSString* nameMayBeNull = jsCast<JSBoundFunction*>(this)->nameMayBeNull(); | 
 |         JSString* string = nullptr; | 
 |         if (nameMayBeNull) { | 
 |             string = jsString(globalObject, vm.smallStrings.boundPrefixString(), nameMayBeNull); | 
 |             RETURN_IF_EXCEPTION(scope, PropertyStatus::Lazy); | 
 |         } else | 
 |             string = jsEmptyString(vm); | 
 |         unsigned initialAttributes = PropertyAttribute::DontEnum | PropertyAttribute::ReadOnly; | 
 |         rareData->setHasReifiedName(); | 
 |         putDirect(vm, nameIdent, string, initialAttributes); | 
 |     } | 
 |     return PropertyStatus::Reified; | 
 | } | 
 |  | 
 | #if ASSERT_ENABLED | 
 | void JSFunction::assertTypeInfoFlagInvariants() | 
 | { | 
 |     // If you change this, you'll need to update speculationFromClassInfoInheritance. | 
 |     const ClassInfo* info = classInfo(vm()); | 
 |     if (!(inlineTypeFlags() & ImplementsDefaultHasInstance)) | 
 |         RELEASE_ASSERT(info == JSBoundFunction::info()); | 
 |     else | 
 |         RELEASE_ASSERT(info != JSBoundFunction::info()); | 
 | } | 
 | #endif // ASSERT_ENABLED | 
 |  | 
 | } // namespace JSC |