diff options
Diffstat (limited to 'js/src/vm/GlobalObject.h')
| -rw-r--r-- | js/src/vm/GlobalObject.h | 1203 |
1 files changed, 1203 insertions, 0 deletions
diff --git a/js/src/vm/GlobalObject.h b/js/src/vm/GlobalObject.h new file mode 100644 index 0000000000..92dec6698f --- /dev/null +++ b/js/src/vm/GlobalObject.h @@ -0,0 +1,1203 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- + * vim: set ts=8 sts=2 et sw=2 tw=80: + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef vm_GlobalObject_h +#define vm_GlobalObject_h + +#include "js/GlobalObject.h" + +#include "mozilla/Assertions.h" +#include "mozilla/EnumeratedArray.h" + +#include <stdint.h> +#include <type_traits> + +#include "jsexn.h" +#include "jsfriendapi.h" +#include "jspubtd.h" +#include "jstypes.h" +#include "NamespaceImports.h" + +#include "gc/AllocKind.h" +#include "js/CallArgs.h" +#include "js/Class.h" +#include "js/ErrorReport.h" +#include "js/PropertyDescriptor.h" +#include "js/RootingAPI.h" +#include "js/TypeDecls.h" +#include "js/Value.h" +#include "vm/ArrayObject.h" +#include "vm/JSAtomState.h" +#include "vm/JSContext.h" +#include "vm/JSFunction.h" +#include "vm/JSObject.h" +#include "vm/NativeObject.h" +#include "vm/Realm.h" +#include "vm/RegExpShared.h" +#include "vm/Shape.h" +#include "vm/StringType.h" + +struct JSFunctionSpec; +class JSJitInfo; +struct JSPrincipals; +struct JSPropertySpec; + +namespace JS { +class JS_PUBLIC_API RealmOptions; +}; + +namespace js { + +class ArgumentsObject; +class GlobalScope; +class GlobalLexicalEnvironmentObject; +class PlainObject; +class PropertyIteratorObject; +class RegExpStatics; + +namespace gc { +class FinalizationRegistryGlobalData; +} // namespace gc + +// Fixed slot capacities for PlainObjects. The global has a cached Shape for +// PlainObject with default prototype for each of these values. +enum class PlainObjectSlotsKind { + Slots0, + Slots2, + Slots4, + Slots8, + Slots12, + Slots16, + Limit +}; + +static PlainObjectSlotsKind PlainObjectSlotsKindFromAllocKind( + gc::AllocKind kind) { + switch (kind) { + case gc::AllocKind::OBJECT0: + return PlainObjectSlotsKind::Slots0; + case gc::AllocKind::OBJECT2: + return PlainObjectSlotsKind::Slots2; + case gc::AllocKind::OBJECT4: + return PlainObjectSlotsKind::Slots4; + case gc::AllocKind::OBJECT8: + return PlainObjectSlotsKind::Slots8; + case gc::AllocKind::OBJECT12: + return PlainObjectSlotsKind::Slots12; + case gc::AllocKind::OBJECT16: + return PlainObjectSlotsKind::Slots16; + default: + break; + } + MOZ_CRASH("Invalid kind"); +} + +// Data attached to a GlobalObject. This is freed when clearing the Realm's +// global_ only because this way we don't need to add a finalizer to all +// GlobalObject JSClasses. +class GlobalObjectData { + friend class js::GlobalObject; + + GlobalObjectData(const GlobalObjectData&) = delete; + void operator=(const GlobalObjectData&) = delete; + + public: + explicit GlobalObjectData(Zone* zone); + + ~GlobalObjectData(); + + // The global environment record's [[VarNames]] list that contains all + // names declared using FunctionDeclaration, GeneratorDeclaration, and + // VariableDeclaration declarations in global code in this global's realm. + // Names are only removed from this list by a |delete IdentifierReference| + // that successfully removes that global property. + using VarNamesSet = + GCHashSet<HeapPtr<JSAtom*>, DefaultHasher<JSAtom*>, CellAllocPolicy>; + VarNamesSet varNames; + + // The original values for built-in constructors (with their prototype + // objects) based on JSProtoKey. + // + // This is necessary to implement spec language speaking in terms of "the + // original Array prototype object", or "as if by the expression new Array()" + // referring to the original Array constructor. The actual (writable and even + // deletable) Object, Array, &c. properties are not stored here. + struct ConstructorWithProto { + HeapPtr<JSObject*> constructor; + HeapPtr<JSObject*> prototype; + }; + using CtorArray = + mozilla::EnumeratedArray<JSProtoKey, JSProto_LIMIT, ConstructorWithProto>; + CtorArray builtinConstructors; + + // Built-in prototypes for this global. Note that this is different from the + // set of built-in constructors/prototypes based on JSProtoKey. + enum class ProtoKind { + IteratorProto, + ArrayIteratorProto, + StringIteratorProto, + RegExpStringIteratorProto, + GeneratorObjectProto, + AsyncIteratorProto, + AsyncFromSyncIteratorProto, + AsyncGeneratorProto, + MapIteratorProto, + SetIteratorProto, + WrapForValidIteratorProto, + IteratorHelperProto, + AsyncIteratorHelperProto, + SegmentsProto, + SegmentIteratorProto, + + Limit + }; + using ProtoArray = + mozilla::EnumeratedArray<ProtoKind, ProtoKind::Limit, HeapPtr<JSObject*>>; + ProtoArray builtinProtos; + + HeapPtr<GlobalScope*> emptyGlobalScope; + + // The lexical environment for global let/const/class bindings. + HeapPtr<GlobalLexicalEnvironmentObject*> lexicalEnvironment; + + // The WindowProxy associated with this global. + HeapPtr<JSObject*> windowProxy; + + // Functions and other top-level values for self-hosted code. The "computed" + // holder is used as the target of `SetIntrinsic` calls, but the same property + // may also be cached on the normal intrinsics holder for `GetIntrinsic`. + HeapPtr<NativeObject*> intrinsicsHolder; + HeapPtr<NativeObject*> computedIntrinsicsHolder; + + // Cache used to optimize certain for-of operations. + HeapPtr<NativeObject*> forOfPICChain; + + // List of source URLs for this realm. This is used by the debugger. + HeapPtr<ArrayObject*> sourceURLsHolder; + + // Realm-specific object that can be used as key in WeakMaps. + HeapPtr<PlainObject*> realmKeyObject; + + // The unique %ThrowTypeError% function for this global. + HeapPtr<JSFunction*> throwTypeError; + + // The unique %eval% function (for indirect eval) for this global. + HeapPtr<JSFunction*> eval; + + // Empty iterator object used for for-in with null/undefined. + HeapPtr<PropertyIteratorObject*> emptyIterator; + + // Cached shape for new arrays with Array.prototype as prototype. + HeapPtr<SharedShape*> arrayShapeWithDefaultProto; + + // Shape for PlainObject with %Object.prototype% as proto, for each object + // AllocKind. + using PlainObjectShapeArray = mozilla::EnumeratedArray< + PlainObjectSlotsKind, PlainObjectSlotsKind::Limit, HeapPtr<SharedShape*>>; + PlainObjectShapeArray plainObjectShapesWithDefaultProto; + + // Shape for JSFunction with %Function.prototype% as proto, for both + // non-extended and extended functions. + HeapPtr<SharedShape*> functionShapeWithDefaultProto; + HeapPtr<SharedShape*> extendedFunctionShapeWithDefaultProto; + + // Shape for BoundFunctionObject with %Function.prototype% as proto. + HeapPtr<SharedShape*> boundFunctionShapeWithDefaultProto; + + // Global state for regular expressions. + RegExpRealm regExpRealm; + + HeapPtr<ArgumentsObject*> mappedArgumentsTemplate; + HeapPtr<ArgumentsObject*> unmappedArgumentsTemplate; + + HeapPtr<PlainObject*> iterResultTemplate; + HeapPtr<PlainObject*> iterResultWithoutPrototypeTemplate; + + // Lazily initialized script source object to use for scripts cloned from the + // self-hosting stencil. + HeapPtr<ScriptSourceObject*> selfHostingScriptSource; + + UniquePtr<gc::FinalizationRegistryGlobalData> finalizationRegistryData; + + // The number of times that one of the following has occurred: + // 1. A property of this GlobalObject is deleted. + // 2. A data property of this GlobalObject is converted to an accessor, + // or vice versa. + // 3. A property is defined on the global lexical that shadows a property on + // this GlobalObject. + uint32_t generationCount = 0; + + // Whether the |globalThis| property has been resolved on the global object. + bool globalThisResolved = false; + + void trace(JSTracer* trc, GlobalObject* global); + void addSizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf, + JS::ClassInfo* info) const; + + static constexpr size_t offsetOfLexicalEnvironment() { + static_assert(sizeof(lexicalEnvironment) == sizeof(uintptr_t), + "JIT code assumes field is pointer-sized"); + return offsetof(GlobalObjectData, lexicalEnvironment); + } + static constexpr size_t offsetOfRegExpRealm() { + return offsetof(GlobalObjectData, regExpRealm); + } +}; + +class GlobalObject : public NativeObject { + enum : unsigned { + GLOBAL_DATA_SLOT = JSCLASS_GLOBAL_APPLICATION_SLOTS, + + // Total reserved-slot count for global objects. + RESERVED_SLOTS + }; + + // The slot count must be in the public API for JSCLASS_GLOBAL_FLAGS, and + // we won't expose GlobalObject, so just assert that the two values are + // synchronized. + static_assert(JSCLASS_GLOBAL_SLOT_COUNT == RESERVED_SLOTS, + "global object slot counts are inconsistent"); + + // Ensure GlobalObjectData is only one dereference away. + static_assert(GLOBAL_DATA_SLOT < MAX_FIXED_SLOTS, + "GlobalObjectData should be stored in a fixed slot for " + "performance reasons"); + + using ProtoKind = GlobalObjectData::ProtoKind; + + GlobalObjectData* maybeData() { + Value v = getReservedSlot(GLOBAL_DATA_SLOT); + return static_cast<GlobalObjectData*>(v.toPrivate()); + } + const GlobalObjectData* maybeData() const { + Value v = getReservedSlot(GLOBAL_DATA_SLOT); + return static_cast<const GlobalObjectData*>(v.toPrivate()); + } + + GlobalObjectData& data() { return *maybeData(); } + const GlobalObjectData& data() const { return *maybeData(); } + + void initBuiltinProto(ProtoKind kind, JSObject* proto) { + MOZ_ASSERT(proto); + data().builtinProtos[kind].init(proto); + } + bool hasBuiltinProto(ProtoKind kind) const { + return bool(data().builtinProtos[kind]); + } + JSObject* maybeBuiltinProto(ProtoKind kind) const { + return data().builtinProtos[kind]; + } + JSObject& getBuiltinProto(ProtoKind kind) const { + MOZ_ASSERT(hasBuiltinProto(kind)); + return *data().builtinProtos[kind]; + } + + public: + GlobalLexicalEnvironmentObject& lexicalEnvironment() { + return *data().lexicalEnvironment; + } + GlobalScope& emptyGlobalScope() const; + + void traceData(JSTracer* trc, GlobalObject* global) { + data().trace(trc, global); + } + void releaseData(JS::GCContext* gcx); + + void addSizeOfData(mozilla::MallocSizeOf mallocSizeOf, + JS::ClassInfo* info) const { + if (maybeData()) { + data().addSizeOfIncludingThis(mallocSizeOf, info); + } + } + + void setOriginalEval(JSFunction* evalFun) { + MOZ_ASSERT(!data().eval); + data().eval.init(evalFun); + } + + bool hasConstructor(JSProtoKey key) const { + return bool(data().builtinConstructors[key].constructor); + } + JSObject& getConstructor(JSProtoKey key) const { + MOZ_ASSERT(hasConstructor(key)); + return *maybeGetConstructor(key); + } + + static bool skipDeselectedConstructor(JSContext* cx, JSProtoKey key); + + private: + enum class IfClassIsDisabled { DoNothing, Throw }; + + static bool resolveConstructor(JSContext* cx, Handle<GlobalObject*> global, + JSProtoKey key, IfClassIsDisabled mode); + + public: + static bool ensureConstructor(JSContext* cx, Handle<GlobalObject*> global, + JSProtoKey key) { + if (global->isStandardClassResolved(key)) { + return true; + } + return resolveConstructor(cx, global, key, IfClassIsDisabled::Throw); + } + + static JSObject* getOrCreateConstructor(JSContext* cx, JSProtoKey key) { + MOZ_ASSERT(key != JSProto_Null); + Handle<GlobalObject*> global = cx->global(); + if (!GlobalObject::ensureConstructor(cx, global, key)) { + return nullptr; + } + return &global->getConstructor(key); + } + + static JSObject* getOrCreatePrototype(JSContext* cx, JSProtoKey key) { + MOZ_ASSERT(key != JSProto_Null); + Handle<GlobalObject*> global = cx->global(); + if (!GlobalObject::ensureConstructor(cx, global, key)) { + return nullptr; + } + return &global->getPrototype(key); + } + + static JS::Handle<JSObject*> getOrCreatePrototypeHandle(JSContext* cx, + JSProtoKey key) { + MOZ_ASSERT(key != JSProto_Null); + Handle<GlobalObject*> global = cx->global(); + if (!GlobalObject::ensureConstructor(cx, global, key)) { + return nullptr; + } + return global->getPrototypeHandle(key); + } + + JSObject* maybeGetConstructor(JSProtoKey protoKey) const { + MOZ_ASSERT(JSProto_Null < protoKey); + MOZ_ASSERT(protoKey < JSProto_LIMIT); + return data().builtinConstructors[protoKey].constructor; + } + + JSObject* maybeGetPrototype(JSProtoKey protoKey) const { + MOZ_ASSERT(JSProto_Null < protoKey); + MOZ_ASSERT(protoKey < JSProto_LIMIT); + return data().builtinConstructors[protoKey].prototype; + } + + static bool maybeResolveGlobalThis(JSContext* cx, + Handle<GlobalObject*> global, + bool* resolved); + + void setConstructor(JSProtoKey key, JSObject* obj) { + MOZ_ASSERT(obj); + data().builtinConstructors[key].constructor = obj; + } + + bool hasPrototype(JSProtoKey key) const { + return bool(data().builtinConstructors[key].prototype); + } + JSObject& getPrototype(JSProtoKey key) const { + MOZ_ASSERT(hasPrototype(key)); + return *maybeGetPrototype(key); + } + + JS::Handle<JSObject*> getPrototypeHandle(JSProtoKey protoKey) const { + MOZ_ASSERT(hasPrototype(protoKey)); + MOZ_ASSERT(JSProto_Null < protoKey); + MOZ_ASSERT(protoKey < JSProto_LIMIT); + return Handle<JSObject*>::fromMarkedLocation( + &data().builtinConstructors[protoKey].prototype.get()); + } + + void setPrototype(JSProtoKey key, JSObject* obj) { + MOZ_ASSERT(obj); + data().builtinConstructors[key].prototype = obj; + } + + /* + * Lazy standard classes need a way to indicate they have been initialized. + * Otherwise, when we delete them, we might accidentally recreate them via + * a lazy initialization. We use the presence of an object in the constructor + * array to indicate that they've been initialized. + * + * Note: A few builtin objects, like JSON and Math, are not constructors, + * so getConstructor is a bit of a misnomer. + */ + bool isStandardClassResolved(JSProtoKey key) const { + return hasConstructor(key); + } + + private: + bool classIsInitialized(JSProtoKey key) const { + bool inited = hasConstructor(key); + MOZ_ASSERT(inited == hasPrototype(key)); + return inited; + } + + bool functionObjectClassesInitialized() const { + bool inited = classIsInitialized(JSProto_Function); + MOZ_ASSERT(inited == classIsInitialized(JSProto_Object)); + return inited; + } + + // Disallow use of unqualified JSObject::create in GlobalObject. + static GlobalObject* create(...) = delete; + + friend struct ::JSRuntime; + static GlobalObject* createInternal(JSContext* cx, const JSClass* clasp); + + public: + static GlobalObject* new_(JSContext* cx, const JSClass* clasp, + JSPrincipals* principals, + JS::OnNewGlobalHookOption hookOption, + const JS::RealmOptions& options); + + /* + * Create a constructor function with the specified name and length using + * ctor, a method which creates objects with the given class. + */ + static JSFunction* createConstructor( + JSContext* cx, JSNative ctor, JSAtom* name, unsigned length, + gc::AllocKind kind = gc::AllocKind::FUNCTION, + const JSJitInfo* jitInfo = nullptr); + + /* + * Create an object to serve as [[Prototype]] for instances of the given + * class, using |Object.prototype| as its [[Prototype]]. Users creating + * prototype objects with particular internal structure (e.g. reserved + * slots guaranteed to contain values of particular types) must immediately + * complete the minimal initialization to make the returned object safe to + * touch. + */ + static NativeObject* createBlankPrototype( + JSContext* cx, Handle<GlobalObject*> global, const JSClass* clasp, + ObjectFlags objFlags = ObjectFlags()); + + /* + * Identical to createBlankPrototype, but uses proto as the [[Prototype]] + * of the returned blank prototype. + */ + static NativeObject* createBlankPrototypeInheriting(JSContext* cx, + const JSClass* clasp, + HandleObject proto); + + template <typename T> + static T* createBlankPrototypeInheriting(JSContext* cx, HandleObject proto) { + NativeObject* res = createBlankPrototypeInheriting(cx, &T::class_, proto); + return res ? &res->template as<T>() : nullptr; + } + + template <typename T> + static T* createBlankPrototype(JSContext* cx, Handle<GlobalObject*> global, + ObjectFlags objFlags = ObjectFlags()) { + NativeObject* res = createBlankPrototype(cx, global, &T::class_, objFlags); + return res ? &res->template as<T>() : nullptr; + } + + // Object, Function, and eval are eagerly resolved when creating the global. + JSObject& getObjectPrototype() { + MOZ_ASSERT(functionObjectClassesInitialized()); + return getPrototype(JSProto_Object); + } + Handle<JSObject*> getObjectPrototypeHandle() { + MOZ_ASSERT(functionObjectClassesInitialized()); + return getPrototypeHandle(JSProto_Object); + } + JSObject& getFunctionConstructor() { + MOZ_ASSERT(functionObjectClassesInitialized()); + return getConstructor(JSProto_Function); + } + JSObject& getFunctionPrototype() { + MOZ_ASSERT(functionObjectClassesInitialized()); + return getPrototype(JSProto_Function); + } + JSFunction& getEvalFunction() { + MOZ_ASSERT(data().eval); + return *data().eval; + } + + static NativeObject* getOrCreateArrayPrototype(JSContext* cx, + Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_Array)) { + return nullptr; + } + return &global->getPrototype(JSProto_Array).as<NativeObject>(); + } + + NativeObject* maybeGetArrayPrototype() { + if (classIsInitialized(JSProto_Array)) { + return &getPrototype(JSProto_Array).as<NativeObject>(); + } + return nullptr; + } + + static JSObject* getOrCreateBooleanPrototype(JSContext* cx, + Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_Boolean)) { + return nullptr; + } + return &global->getPrototype(JSProto_Boolean); + } + + static JSObject* getOrCreateNumberPrototype(JSContext* cx, + Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_Number)) { + return nullptr; + } + return &global->getPrototype(JSProto_Number); + } + + static JSObject* getOrCreateStringPrototype(JSContext* cx, + Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_String)) { + return nullptr; + } + return &global->getPrototype(JSProto_String); + } + + static JSObject* getOrCreateSymbolPrototype(JSContext* cx, + Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_Symbol)) { + return nullptr; + } + return &global->getPrototype(JSProto_Symbol); + } + + static JSObject* getOrCreateBigIntPrototype(JSContext* cx, + Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_BigInt)) { + return nullptr; + } + return &global->getPrototype(JSProto_BigInt); + } + +#ifdef ENABLE_RECORD_TUPLE + static JSObject* getOrCreateRecordPrototype(JSContext* cx, + Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_Record)) { + return nullptr; + } + return &global->getPrototype(JSProto_Record); + } + + static JSObject* getOrCreateTuplePrototype(JSContext* cx, + Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_Tuple)) { + return nullptr; + } + return &global->getPrototype(JSProto_Tuple); + } +#endif + + static JSObject* getOrCreatePromisePrototype(JSContext* cx, + Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_Promise)) { + return nullptr; + } + return &global->getPrototype(JSProto_Promise); + } + + static JSObject* getOrCreateRegExpPrototype(JSContext* cx, + Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_RegExp)) { + return nullptr; + } + return &global->getPrototype(JSProto_RegExp); + } + + JSObject* maybeGetRegExpPrototype() { + if (classIsInitialized(JSProto_RegExp)) { + return &getPrototype(JSProto_RegExp); + } + return nullptr; + } + + static JSObject* getOrCreateSavedFramePrototype( + JSContext* cx, Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_SavedFrame)) { + return nullptr; + } + return &global->getPrototype(JSProto_SavedFrame); + } + + static JSObject* getOrCreateArrayBufferConstructor( + JSContext* cx, Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_ArrayBuffer)) { + return nullptr; + } + return &global->getConstructor(JSProto_ArrayBuffer); + } + + static JSObject* getOrCreateArrayBufferPrototype( + JSContext* cx, Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_ArrayBuffer)) { + return nullptr; + } + return &global->getPrototype(JSProto_ArrayBuffer); + } + + static JSObject* getOrCreateSharedArrayBufferPrototype( + JSContext* cx, Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_SharedArrayBuffer)) { + return nullptr; + } + return &global->getPrototype(JSProto_SharedArrayBuffer); + } + + static JSObject* getOrCreateCustomErrorPrototype(JSContext* cx, + Handle<GlobalObject*> global, + JSExnType exnType) { + JSProtoKey key = GetExceptionProtoKey(exnType); + if (!ensureConstructor(cx, global, key)) { + return nullptr; + } + return &global->getPrototype(key); + } + + static JSFunction* getOrCreateErrorConstructor(JSContext* cx, + Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_Error)) { + return nullptr; + } + return &global->getConstructor(JSProto_Error).as<JSFunction>(); + } + + static JSObject* getOrCreateErrorPrototype(JSContext* cx, + Handle<GlobalObject*> global) { + return getOrCreateCustomErrorPrototype(cx, global, JSEXN_ERR); + } + + static NativeObject* getOrCreateSetPrototype(JSContext* cx, + Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_Set)) { + return nullptr; + } + return &global->getPrototype(JSProto_Set).as<NativeObject>(); + } + + static NativeObject* getOrCreateWeakSetPrototype( + JSContext* cx, Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_WeakSet)) { + return nullptr; + } + return &global->getPrototype(JSProto_WeakSet).as<NativeObject>(); + } + + static JSFunction* getOrCreateTypedArrayConstructor( + JSContext* cx, Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_TypedArray)) { + return nullptr; + } + return &global->getConstructor(JSProto_TypedArray).as<JSFunction>(); + } + + static JSObject* getOrCreateTypedArrayPrototype( + JSContext* cx, Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_TypedArray)) { + return nullptr; + } + return &global->getPrototype(JSProto_TypedArray); + } + + private: + using ObjectInitOp = bool (*)(JSContext*, Handle<GlobalObject*>); + using ObjectInitWithTagOp = bool (*)(JSContext*, Handle<GlobalObject*>, + Handle<JSAtom*>); + + static JSObject* getOrCreateBuiltinProto(JSContext* cx, + Handle<GlobalObject*> global, + ProtoKind kind, ObjectInitOp init) { + if (JSObject* proto = global->maybeBuiltinProto(kind)) { + return proto; + } + + return createBuiltinProto(cx, global, kind, init); + } + + static JSObject* getOrCreateBuiltinProto(JSContext* cx, + Handle<GlobalObject*> global, + ProtoKind kind, Handle<JSAtom*> tag, + ObjectInitWithTagOp init) { + if (JSObject* proto = global->maybeBuiltinProto(kind)) { + return proto; + } + + return createBuiltinProto(cx, global, kind, tag, init); + } + + static JSObject* createBuiltinProto(JSContext* cx, + Handle<GlobalObject*> global, + ProtoKind kind, ObjectInitOp init); + static JSObject* createBuiltinProto(JSContext* cx, + Handle<GlobalObject*> global, + ProtoKind kind, Handle<JSAtom*> tag, + ObjectInitWithTagOp init); + + static JSObject* createIteratorPrototype(JSContext* cx, + Handle<GlobalObject*> global); + + public: + NativeObject* maybeGetIteratorPrototype() { + if (JSObject* obj = maybeBuiltinProto(ProtoKind::IteratorProto)) { + return &obj->as<NativeObject>(); + } + return nullptr; + } + + static JSObject* getOrCreateIteratorPrototype(JSContext* cx, + Handle<GlobalObject*> global) { + if (JSObject* proto = global->maybeBuiltinProto(ProtoKind::IteratorProto)) { + return proto; + } + return createIteratorPrototype(cx, global); + } + + static NativeObject* getOrCreateArrayIteratorPrototype( + JSContext* cx, Handle<GlobalObject*> global); + + NativeObject* maybeGetArrayIteratorPrototype() { + if (JSObject* obj = maybeBuiltinProto(ProtoKind::ArrayIteratorProto)) { + return &obj->as<NativeObject>(); + } + return nullptr; + } + + static JSObject* getOrCreateStringIteratorPrototype( + JSContext* cx, Handle<GlobalObject*> global); + + static JSObject* getOrCreateRegExpStringIteratorPrototype( + JSContext* cx, Handle<GlobalObject*> global); + + void setGeneratorObjectPrototype(JSObject* obj) { + initBuiltinProto(ProtoKind::GeneratorObjectProto, obj); + } + + static JSObject* getOrCreateGeneratorObjectPrototype( + JSContext* cx, Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_GeneratorFunction)) { + return nullptr; + } + return &global->getBuiltinProto(ProtoKind::GeneratorObjectProto); + } + + static JSObject* getOrCreateGeneratorFunctionPrototype( + JSContext* cx, Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_GeneratorFunction)) { + return nullptr; + } + return &global->getPrototype(JSProto_GeneratorFunction); + } + + static JSObject* getOrCreateGeneratorFunction(JSContext* cx, + Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_GeneratorFunction)) { + return nullptr; + } + return &global->getConstructor(JSProto_GeneratorFunction); + } + + static JSObject* getOrCreateAsyncFunctionPrototype( + JSContext* cx, Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_AsyncFunction)) { + return nullptr; + } + return &global->getPrototype(JSProto_AsyncFunction); + } + + static JSObject* getOrCreateAsyncFunction(JSContext* cx, + Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_AsyncFunction)) { + return nullptr; + } + return &global->getConstructor(JSProto_AsyncFunction); + } + + static JSObject* createAsyncIteratorPrototype(JSContext* cx, + Handle<GlobalObject*> global); + + static JSObject* getOrCreateAsyncIteratorPrototype( + JSContext* cx, Handle<GlobalObject*> global) { + if (JSObject* proto = + global->maybeBuiltinProto(ProtoKind::AsyncIteratorProto)) { + return proto; + } + return createAsyncIteratorPrototype(cx, global); + } + + static JSObject* getOrCreateAsyncFromSyncIteratorPrototype( + JSContext* cx, Handle<GlobalObject*> global) { + return getOrCreateBuiltinProto(cx, global, + ProtoKind::AsyncFromSyncIteratorProto, + initAsyncFromSyncIteratorProto); + } + + static JSObject* getOrCreateAsyncGenerator(JSContext* cx, + Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_AsyncGeneratorFunction)) { + return nullptr; + } + return &global->getPrototype(JSProto_AsyncGeneratorFunction); + } + + static JSObject* getOrCreateAsyncGeneratorFunction( + JSContext* cx, Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_AsyncGeneratorFunction)) { + return nullptr; + } + return &global->getConstructor(JSProto_AsyncGeneratorFunction); + } + + void setAsyncGeneratorPrototype(JSObject* obj) { + initBuiltinProto(ProtoKind::AsyncGeneratorProto, obj); + } + + static JSObject* getOrCreateAsyncGeneratorPrototype( + JSContext* cx, Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_AsyncGeneratorFunction)) { + return nullptr; + } + return &global->getBuiltinProto(ProtoKind::AsyncGeneratorProto); + } + + static JSObject* getOrCreateMapIteratorPrototype( + JSContext* cx, Handle<GlobalObject*> global) { + return getOrCreateBuiltinProto(cx, global, ProtoKind::MapIteratorProto, + initMapIteratorProto); + } + + static JSObject* getOrCreateSetIteratorPrototype( + JSContext* cx, Handle<GlobalObject*> global) { + return getOrCreateBuiltinProto(cx, global, ProtoKind::SetIteratorProto, + initSetIteratorProto); + } + + static JSObject* getOrCreateSegmentsPrototype(JSContext* cx, + Handle<GlobalObject*> global) { + return getOrCreateBuiltinProto(cx, global, ProtoKind::SegmentsProto, + initSegmentsProto); + } + + static JSObject* getOrCreateSegmentIteratorPrototype( + JSContext* cx, Handle<GlobalObject*> global) { + return getOrCreateBuiltinProto(cx, global, ProtoKind::SegmentIteratorProto, + initSegmentIteratorProto); + } + + static JSObject* getOrCreateDataViewPrototype(JSContext* cx, + Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_DataView)) { + return nullptr; + } + return &global->getPrototype(JSProto_DataView); + } + + static JSObject* getOrCreatePromiseConstructor(JSContext* cx, + Handle<GlobalObject*> global) { + if (!ensureConstructor(cx, global, JSProto_Promise)) { + return nullptr; + } + return &global->getConstructor(JSProto_Promise); + } + + static NativeObject* getOrCreateWrapForValidIteratorPrototype( + JSContext* cx, Handle<GlobalObject*> global); + + static NativeObject* getOrCreateIteratorHelperPrototype( + JSContext* cx, Handle<GlobalObject*> global); + + static NativeObject* getOrCreateAsyncIteratorHelperPrototype( + JSContext* cx, Handle<GlobalObject*> global); + static bool initAsyncIteratorHelperProto(JSContext* cx, + Handle<GlobalObject*> global); + + NativeObject& getIntrinsicsHolder() const { + MOZ_ASSERT(data().intrinsicsHolder); + return *data().intrinsicsHolder; + } + + static bool createIntrinsicsHolder(JSContext* cx, + Handle<GlobalObject*> global); + + NativeObject* getComputedIntrinsicsHolder() { + return data().computedIntrinsicsHolder; + } + void setComputedIntrinsicsHolder(NativeObject* holder) { + data().computedIntrinsicsHolder = holder; + } + + // If a self-hosting intrinsic with the given |name| exists, it's stored in + // |*vp| and this function returns true. Else it returns false. + bool maybeGetIntrinsicValue(PropertyName* name, Value* vp, JSContext* cx) { + NativeObject& holder = getIntrinsicsHolder(); + + if (mozilla::Maybe<PropertyInfo> prop = holder.lookup(cx, name)) { + *vp = holder.getSlot(prop->slot()); + return true; + } + + return false; + } + + static bool getIntrinsicValue(JSContext* cx, Handle<GlobalObject*> global, + Handle<PropertyName*> name, + MutableHandleValue value) { + // `undefined` in self-hosted JS code should be emitted as JSOp::Undefined. + MOZ_ASSERT(name != cx->names().undefined); + + if (global->maybeGetIntrinsicValue(name, value.address(), cx)) { + return true; + } + return getIntrinsicValueSlow(cx, global, name, value); + } + + static bool getIntrinsicValueSlow(JSContext* cx, Handle<GlobalObject*> global, + Handle<PropertyName*> name, + MutableHandleValue value); + + static bool addIntrinsicValue(JSContext* cx, Handle<GlobalObject*> global, + Handle<PropertyName*> name, HandleValue value); + + static inline bool setIntrinsicValue(JSContext* cx, + Handle<GlobalObject*> global, + Handle<PropertyName*> name, + HandleValue value); + + static bool getSelfHostedFunction(JSContext* cx, Handle<GlobalObject*> global, + Handle<PropertyName*> selfHostedName, + Handle<JSAtom*> name, unsigned nargs, + MutableHandleValue funVal); + + static RegExpStatics* getRegExpStatics(JSContext* cx, + Handle<GlobalObject*> global); + + static JSObject* getOrCreateThrowTypeError(JSContext* cx, + Handle<GlobalObject*> global); + + RegExpRealm& regExpRealm() { return data().regExpRealm; } + + // Infallibly test whether the given value is the eval function for this + // global. + bool valueIsEval(const Value& val); + + void removeFromVarNames(JSAtom* name) { data().varNames.remove(name); } + + // Whether the given name is in [[VarNames]]. + bool isInVarNames(JSAtom* name) { return data().varNames.has(name); } + + // Add a name to [[VarNames]]. Reports OOM on failure. + [[nodiscard]] bool addToVarNames(JSContext* cx, JS::Handle<JSAtom*> name); + + static ArgumentsObject* getOrCreateArgumentsTemplateObject(JSContext* cx, + bool mapped); + ArgumentsObject* maybeArgumentsTemplateObject(bool mapped) const; + + static const size_t IterResultObjectValueSlot = 0; + static const size_t IterResultObjectDoneSlot = 1; + static js::PlainObject* getOrCreateIterResultTemplateObject(JSContext* cx); + static js::PlainObject* getOrCreateIterResultWithoutPrototypeTemplateObject( + JSContext* cx); + + private: + enum class WithObjectPrototype { No, Yes }; + static js::PlainObject* createIterResultTemplateObject( + JSContext* cx, WithObjectPrototype withProto); + + public: + static ScriptSourceObject* getOrCreateSelfHostingScriptSourceObject( + JSContext* cx, Handle<GlobalObject*> global); + + // Implemented in vm/Iteration.cpp. + static bool initIteratorProto(JSContext* cx, Handle<GlobalObject*> global); + template <ProtoKind Kind, const JSClass* ProtoClass, + const JSFunctionSpec* Methods, const bool needsFuseProperty = false> + static bool initObjectIteratorProto(JSContext* cx, + Handle<GlobalObject*> global, + Handle<JSAtom*> tag); + + // Implemented in vm/AsyncIteration.cpp. + static bool initAsyncIteratorProto(JSContext* cx, + Handle<GlobalObject*> global); + static bool initAsyncFromSyncIteratorProto(JSContext* cx, + Handle<GlobalObject*> global); + + // Implemented in builtin/MapObject.cpp. + static bool initMapIteratorProto(JSContext* cx, Handle<GlobalObject*> global); + static bool initSetIteratorProto(JSContext* cx, Handle<GlobalObject*> global); + + // Implemented in builtin/intl/Segmenter.cpp. + static bool initSegmentsProto(JSContext* cx, Handle<GlobalObject*> global); + static bool initSegmentIteratorProto(JSContext* cx, + Handle<GlobalObject*> global); + + static bool initStandardClasses(JSContext* cx, Handle<GlobalObject*> global); + + // Disallow GC as it may mutate the vector. + Realm::DebuggerVector& getDebuggers(const JS::AutoRequireNoGC& nogc) const { + return realm()->getDebuggers(nogc); + } + bool hasDebuggers() const { return realm()->hasDebuggers(); } + + inline NativeObject* getForOfPICObject() { return data().forOfPICChain; } + static NativeObject* getOrCreateForOfPICObject(JSContext* cx, + Handle<GlobalObject*> global); + + JSObject* maybeWindowProxy() const { return data().windowProxy; } + + void setWindowProxy(JSObject* windowProxy) { + // Note: the global must always be associated with the same WindowProxy. + // CacheIR optimizations rely on this by baking in the WindowProxy for the + // global. + MOZ_ASSERT(!data().windowProxy); + data().windowProxy.init(windowProxy); + } + + ArrayObject* getSourceURLsHolder() const { return data().sourceURLsHolder; } + + void setSourceURLsHolder(ArrayObject* holder) { + data().sourceURLsHolder = holder; + } + void clearSourceURLSHolder() { + // This is called at the start of shrinking GCs, so avoids barriers. + data().sourceURLsHolder.unbarrieredSet(nullptr); + } + + SharedShape* maybeArrayShapeWithDefaultProto() const { + return data().arrayShapeWithDefaultProto; + } + + static SharedShape* getArrayShapeWithDefaultProto(JSContext* cx) { + if (SharedShape* shape = cx->global()->data().arrayShapeWithDefaultProto; + MOZ_LIKELY(shape)) { + return shape; + } + return createArrayShapeWithDefaultProto(cx); + } + static SharedShape* createArrayShapeWithDefaultProto(JSContext* cx); + + static SharedShape* getPlainObjectShapeWithDefaultProto(JSContext* cx, + gc::AllocKind kind) { + PlainObjectSlotsKind slotsKind = PlainObjectSlotsKindFromAllocKind(kind); + SharedShape* shape = + cx->global()->data().plainObjectShapesWithDefaultProto[slotsKind]; + if (MOZ_LIKELY(shape)) { + return shape; + } + return createPlainObjectShapeWithDefaultProto(cx, kind); + } + static SharedShape* createPlainObjectShapeWithDefaultProto( + JSContext* cx, gc::AllocKind kind); + + static SharedShape* getEmptyPlainObjectShape(JSContext* cx) { + const PlainObjectSlotsKind kind = PlainObjectSlotsKind::Slots0; + SharedShape* shape = + cx->global()->data().plainObjectShapesWithDefaultProto[kind]; + MOZ_ASSERT(shape); // This is created on initialization. + return shape; + } + + static SharedShape* getFunctionShapeWithDefaultProto(JSContext* cx, + bool extended) { + GlobalObjectData& data = cx->global()->data(); + SharedShape* shape = extended ? data.extendedFunctionShapeWithDefaultProto + : data.functionShapeWithDefaultProto; + if (MOZ_LIKELY(shape)) { + return shape; + } + return createFunctionShapeWithDefaultProto(cx, extended); + } + static SharedShape* createFunctionShapeWithDefaultProto(JSContext* cx, + bool extended); + + SharedShape* maybeBoundFunctionShapeWithDefaultProto() const { + return data().boundFunctionShapeWithDefaultProto; + } + void setBoundFunctionShapeWithDefaultProto(SharedShape* shape) { + data().boundFunctionShapeWithDefaultProto = shape; + } + + static PropertyIteratorObject* getOrCreateEmptyIterator(JSContext* cx); + + // Returns an object that represents the realm, used by embedder. + static JSObject* getOrCreateRealmKeyObject(JSContext* cx, + Handle<GlobalObject*> global); + + gc::FinalizationRegistryGlobalData* getOrCreateFinalizationRegistryData(); + gc::FinalizationRegistryGlobalData* maybeFinalizationRegistryData() const { + return data().finalizationRegistryData.get(); + } + + static size_t offsetOfGlobalDataSlot() { + return getFixedSlotOffset(GLOBAL_DATA_SLOT); + } + + uint32_t generationCount() const { return data().generationCount; } + const void* addressOfGenerationCount() const { + return &data().generationCount; + } + void bumpGenerationCount() { + MOZ_RELEASE_ASSERT(data().generationCount < UINT32_MAX); + data().generationCount++; + } +}; + +/* + * Unless otherwise specified, define ctor.prototype = proto as non-enumerable, + * non-configurable, and non-writable; and define proto.constructor = ctor as + * non-enumerable but configurable and writable. + */ +extern bool LinkConstructorAndPrototype( + JSContext* cx, JSObject* ctor, JSObject* proto, + unsigned prototypeAttrs = JSPROP_PERMANENT | JSPROP_READONLY, + unsigned constructorAttrs = 0); + +/* + * Define properties and/or functions on any object. Either ps or fs, or both, + * may be null. + */ +extern bool DefinePropertiesAndFunctions(JSContext* cx, HandleObject obj, + const JSPropertySpec* ps, + const JSFunctionSpec* fs); + +extern bool DefineToStringTag(JSContext* cx, HandleObject obj, JSAtom* tag); + +/* + * Convenience templates to generic constructor and prototype creation functions + * for ClassSpecs. + */ + +template <JSNative ctor, unsigned length, gc::AllocKind kind, + const JSJitInfo* jitInfo = nullptr> +JSObject* GenericCreateConstructor(JSContext* cx, JSProtoKey key) { + // Note - We duplicate the trick from ClassName() so that we don't need to + // include vm/JSAtomUtils-inl.h here. + PropertyName* name = (&cx->names().Null)[key]; + return GlobalObject::createConstructor(cx, ctor, name, length, kind, jitInfo); +} + +template <typename T> +JSObject* GenericCreatePrototype(JSContext* cx, JSProtoKey key) { + static_assert( + !std::is_same_v<T, PlainObject>, + "creating Object.prototype is very special and isn't handled here"); + MOZ_ASSERT(&T::class_ == ProtoKeyToClass(key), + "type mismatch--probably too much copy/paste in your ClassSpec"); + MOZ_ASSERT( + InheritanceProtoKeyForStandardClass(key) == JSProto_Object, + "subclasses (of anything but Object) can't use GenericCreatePrototype"); + return GlobalObject::createBlankPrototype(cx, cx->global(), &T::protoClass_); +} + +inline JSProtoKey StandardProtoKeyOrNull(const JSObject* obj) { + return JSCLASS_CACHED_PROTO_KEY(obj->getClass()); +} + +JSObject* NewTenuredObjectWithFunctionPrototype(JSContext* cx, + Handle<GlobalObject*> global); + +} // namespace js + +template <> +inline bool JSObject::is<js::GlobalObject>() const { + return !!(getClass()->flags & JSCLASS_IS_GLOBAL); +} + +#endif /* vm_GlobalObject_h */ |