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Diffstat (limited to 'js/src/jsobj.cpp')
| -rw-r--r-- | js/src/jsobj.cpp | 3990 |
1 files changed, 3990 insertions, 0 deletions
diff --git a/js/src/jsobj.cpp b/js/src/jsobj.cpp new file mode 100644 index 000000000..a39a4b0a0 --- /dev/null +++ b/js/src/jsobj.cpp @@ -0,0 +1,3990 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- + * vim: set ts=8 sts=4 et sw=4 tw=99: + * 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/. */ + +/* + * JS object implementation. + */ + +#include "jsobjinlines.h" + +#include "mozilla/ArrayUtils.h" +#include "mozilla/MathAlgorithms.h" +#include "mozilla/MemoryReporting.h" +#include "mozilla/SizePrintfMacros.h" +#include "mozilla/TemplateLib.h" + +#include <string.h> + +#include "jsapi.h" +#include "jsarray.h" +#include "jsatom.h" +#include "jscntxt.h" +#include "jsfriendapi.h" +#include "jsfun.h" +#include "jsgc.h" +#include "jsiter.h" +#include "jsnum.h" +#include "jsopcode.h" +#include "jsprf.h" +#include "jsscript.h" +#include "jsstr.h" +#include "jstypes.h" +#include "jsutil.h" +#include "jswatchpoint.h" +#include "jswin.h" +#include "jswrapper.h" + +#include "builtin/Eval.h" +#include "builtin/Object.h" +#include "builtin/SymbolObject.h" +#include "frontend/BytecodeCompiler.h" +#include "gc/Marking.h" +#include "gc/Policy.h" +#include "jit/BaselineJIT.h" +#include "js/MemoryMetrics.h" +#include "js/Proxy.h" +#include "js/UbiNode.h" +#include "js/UniquePtr.h" +#include "vm/ArgumentsObject.h" +#include "vm/Interpreter.h" +#include "vm/ProxyObject.h" +#include "vm/RegExpStaticsObject.h" +#include "vm/Shape.h" +#include "vm/TypedArrayCommon.h" + +#include "jsatominlines.h" +#include "jsboolinlines.h" +#include "jscntxtinlines.h" +#include "jscompartmentinlines.h" + +#include "vm/ArrayObject-inl.h" +#include "vm/BooleanObject-inl.h" +#include "vm/Caches-inl.h" +#include "vm/Interpreter-inl.h" +#include "vm/NativeObject-inl.h" +#include "vm/NumberObject-inl.h" +#include "vm/Shape-inl.h" +#include "vm/StringObject-inl.h" + +using namespace js; +using namespace js::gc; + +using mozilla::DebugOnly; +using mozilla::Maybe; + +void +js::ReportNotObject(JSContext* cx, const Value& v) +{ + MOZ_ASSERT(!v.isObject()); + + RootedValue value(cx, v); + UniqueChars bytes = DecompileValueGenerator(cx, JSDVG_SEARCH_STACK, value, nullptr); + if (bytes) + JS_ReportErrorNumberLatin1(cx, GetErrorMessage, nullptr, JSMSG_NOT_NONNULL_OBJECT, + bytes.get()); +} + +JS_PUBLIC_API(const char*) +JS::InformalValueTypeName(const Value& v) +{ + if (v.isObject()) + return v.toObject().getClass()->name; + if (v.isString()) + return "string"; + if (v.isSymbol()) + return "symbol"; + if (v.isNumber()) + return "number"; + if (v.isBoolean()) + return "boolean"; + if (v.isNull()) + return "null"; + if (v.isUndefined()) + return "undefined"; + return "value"; +} + +// ES6 draft rev37 6.2.4.4 FromPropertyDescriptor +JS_PUBLIC_API(bool) +JS::FromPropertyDescriptor(JSContext* cx, Handle<PropertyDescriptor> desc, MutableHandleValue vp) +{ + AssertHeapIsIdle(cx); + CHECK_REQUEST(cx); + assertSameCompartment(cx, desc); + + // Step 1. + if (!desc.object()) { + vp.setUndefined(); + return true; + } + + return FromPropertyDescriptorToObject(cx, desc, vp); +} + +bool +js::FromPropertyDescriptorToObject(JSContext* cx, Handle<PropertyDescriptor> desc, + MutableHandleValue vp) +{ + // Step 2-3. + RootedObject obj(cx, NewBuiltinClassInstance<PlainObject>(cx)); + if (!obj) + return false; + + const JSAtomState& names = cx->names(); + + // Step 4. + if (desc.hasValue()) { + if (!DefineProperty(cx, obj, names.value, desc.value())) + return false; + } + + // Step 5. + RootedValue v(cx); + if (desc.hasWritable()) { + v.setBoolean(desc.writable()); + if (!DefineProperty(cx, obj, names.writable, v)) + return false; + } + + // Step 6. + if (desc.hasGetterObject()) { + if (JSObject* get = desc.getterObject()) + v.setObject(*get); + else + v.setUndefined(); + if (!DefineProperty(cx, obj, names.get, v)) + return false; + } + + // Step 7. + if (desc.hasSetterObject()) { + if (JSObject* set = desc.setterObject()) + v.setObject(*set); + else + v.setUndefined(); + if (!DefineProperty(cx, obj, names.set, v)) + return false; + } + + // Step 8. + if (desc.hasEnumerable()) { + v.setBoolean(desc.enumerable()); + if (!DefineProperty(cx, obj, names.enumerable, v)) + return false; + } + + // Step 9. + if (desc.hasConfigurable()) { + v.setBoolean(desc.configurable()); + if (!DefineProperty(cx, obj, names.configurable, v)) + return false; + } + + vp.setObject(*obj); + return true; +} + +bool +js::GetFirstArgumentAsObject(JSContext* cx, const CallArgs& args, const char* method, + MutableHandleObject objp) +{ + if (args.length() == 0) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_MORE_ARGS_NEEDED, + method, "0", "s"); + return false; + } + + HandleValue v = args[0]; + if (!v.isObject()) { + UniqueChars bytes = DecompileValueGenerator(cx, JSDVG_SEARCH_STACK, v, nullptr); + if (!bytes) + return false; + JS_ReportErrorNumberLatin1(cx, GetErrorMessage, nullptr, JSMSG_UNEXPECTED_TYPE, + bytes.get(), "not an object"); + return false; + } + + objp.set(&v.toObject()); + return true; +} + +static bool +GetPropertyIfPresent(JSContext* cx, HandleObject obj, HandleId id, MutableHandleValue vp, + bool* foundp) +{ + if (!HasProperty(cx, obj, id, foundp)) + return false; + if (!*foundp) { + vp.setUndefined(); + return true; + } + + return GetProperty(cx, obj, obj, id, vp); +} + +bool +js::Throw(JSContext* cx, jsid id, unsigned errorNumber) +{ + MOZ_ASSERT(js_ErrorFormatString[errorNumber].argCount == 1); + + RootedValue idVal(cx, IdToValue(id)); + JSString* idstr = ValueToSource(cx, idVal); + if (!idstr) + return false; + JSAutoByteString bytes(cx, idstr); + if (!bytes) + return false; + JS_ReportErrorNumberLatin1(cx, GetErrorMessage, nullptr, errorNumber, bytes.ptr()); + return false; +} + +bool +js::Throw(JSContext* cx, JSObject* obj, unsigned errorNumber) +{ + if (js_ErrorFormatString[errorNumber].argCount == 1) { + RootedValue val(cx, ObjectValue(*obj)); + ReportValueErrorFlags(cx, JSREPORT_ERROR, errorNumber, + JSDVG_IGNORE_STACK, val, nullptr, + nullptr, nullptr); + } else { + MOZ_ASSERT(js_ErrorFormatString[errorNumber].argCount == 0); + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, errorNumber); + } + return false; +} + + +/*** PropertyDescriptor operations and DefineProperties ******************************************/ + +bool +CheckCallable(JSContext* cx, JSObject* obj, const char* fieldName) +{ + if (obj && !obj->isCallable()) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_BAD_GET_SET_FIELD, + fieldName); + return false; + } + return true; +} + +bool +js::ToPropertyDescriptor(JSContext* cx, HandleValue descval, bool checkAccessors, + MutableHandle<PropertyDescriptor> desc) +{ + // step 2 + RootedObject obj(cx, NonNullObject(cx, descval)); + if (!obj) + return false; + + // step 3 + desc.clear(); + + bool found = false; + RootedId id(cx); + RootedValue v(cx); + unsigned attrs = 0; + + // step 4 + id = NameToId(cx->names().enumerable); + if (!GetPropertyIfPresent(cx, obj, id, &v, &found)) + return false; + if (found) { + if (ToBoolean(v)) + attrs |= JSPROP_ENUMERATE; + } else { + attrs |= JSPROP_IGNORE_ENUMERATE; + } + + // step 5 + id = NameToId(cx->names().configurable); + if (!GetPropertyIfPresent(cx, obj, id, &v, &found)) + return false; + if (found) { + if (!ToBoolean(v)) + attrs |= JSPROP_PERMANENT; + } else { + attrs |= JSPROP_IGNORE_PERMANENT; + } + + // step 6 + id = NameToId(cx->names().value); + if (!GetPropertyIfPresent(cx, obj, id, &v, &found)) + return false; + if (found) + desc.value().set(v); + else + attrs |= JSPROP_IGNORE_VALUE; + + // step 7 + id = NameToId(cx->names().writable); + if (!GetPropertyIfPresent(cx, obj, id, &v, &found)) + return false; + if (found) { + if (!ToBoolean(v)) + attrs |= JSPROP_READONLY; + } else { + attrs |= JSPROP_IGNORE_READONLY; + } + + // step 8 + bool hasGetOrSet; + id = NameToId(cx->names().get); + if (!GetPropertyIfPresent(cx, obj, id, &v, &found)) + return false; + hasGetOrSet = found; + if (found) { + if (v.isObject()) { + if (checkAccessors && !CheckCallable(cx, &v.toObject(), js_getter_str)) + return false; + desc.setGetterObject(&v.toObject()); + } else if (!v.isUndefined()) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_BAD_GET_SET_FIELD, + js_getter_str); + return false; + } + attrs |= JSPROP_GETTER | JSPROP_SHARED; + } + + // step 9 + id = NameToId(cx->names().set); + if (!GetPropertyIfPresent(cx, obj, id, &v, &found)) + return false; + hasGetOrSet |= found; + if (found) { + if (v.isObject()) { + if (checkAccessors && !CheckCallable(cx, &v.toObject(), js_setter_str)) + return false; + desc.setSetterObject(&v.toObject()); + } else if (!v.isUndefined()) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_BAD_GET_SET_FIELD, + js_setter_str); + return false; + } + attrs |= JSPROP_SETTER | JSPROP_SHARED; + } + + // step 10 + if (hasGetOrSet) { + if (!(attrs & JSPROP_IGNORE_READONLY) || !(attrs & JSPROP_IGNORE_VALUE)) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_INVALID_DESCRIPTOR); + return false; + } + + // By convention, these bits are not used on accessor descriptors. + attrs &= ~(JSPROP_IGNORE_READONLY | JSPROP_IGNORE_VALUE); + } + + desc.setAttributes(attrs); + MOZ_ASSERT_IF(attrs & JSPROP_READONLY, !(attrs & (JSPROP_GETTER | JSPROP_SETTER))); + MOZ_ASSERT_IF(attrs & (JSPROP_GETTER | JSPROP_SETTER), attrs & JSPROP_SHARED); + return true; +} + +bool +js::CheckPropertyDescriptorAccessors(JSContext* cx, Handle<PropertyDescriptor> desc) +{ + if (desc.hasGetterObject()) { + if (!CheckCallable(cx, desc.getterObject(), js_getter_str)) + return false; + } + if (desc.hasSetterObject()) { + if (!CheckCallable(cx, desc.setterObject(), js_setter_str)) + return false; + } + return true; +} + +void +js::CompletePropertyDescriptor(MutableHandle<PropertyDescriptor> desc) +{ + desc.assertValid(); + + if (desc.isGenericDescriptor() || desc.isDataDescriptor()) { + if (!desc.hasWritable()) + desc.attributesRef() |= JSPROP_READONLY; + desc.attributesRef() &= ~(JSPROP_IGNORE_READONLY | JSPROP_IGNORE_VALUE); + } else { + if (!desc.hasGetterObject()) + desc.setGetterObject(nullptr); + if (!desc.hasSetterObject()) + desc.setSetterObject(nullptr); + desc.attributesRef() |= JSPROP_GETTER | JSPROP_SETTER | JSPROP_SHARED; + } + if (!desc.hasConfigurable()) + desc.attributesRef() |= JSPROP_PERMANENT; + desc.attributesRef() &= ~(JSPROP_IGNORE_PERMANENT | JSPROP_IGNORE_ENUMERATE); + + desc.assertComplete(); +} + +bool +js::ReadPropertyDescriptors(JSContext* cx, HandleObject props, bool checkAccessors, + AutoIdVector* ids, MutableHandle<PropertyDescriptorVector> descs) +{ + if (!GetPropertyKeys(cx, props, JSITER_OWNONLY | JSITER_SYMBOLS, ids)) + return false; + + RootedId id(cx); + for (size_t i = 0, len = ids->length(); i < len; i++) { + id = (*ids)[i]; + Rooted<PropertyDescriptor> desc(cx); + RootedValue v(cx); + if (!GetProperty(cx, props, props, id, &v) || + !ToPropertyDescriptor(cx, v, checkAccessors, &desc) || + !descs.append(desc)) + { + return false; + } + } + return true; +} + +/*** Seal and freeze *****************************************************************************/ + +static unsigned +GetSealedOrFrozenAttributes(unsigned attrs, IntegrityLevel level) +{ + /* Make all attributes permanent; if freezing, make data attributes read-only. */ + if (level == IntegrityLevel::Frozen && !(attrs & (JSPROP_GETTER | JSPROP_SETTER))) + return JSPROP_PERMANENT | JSPROP_READONLY; + return JSPROP_PERMANENT; +} + +/* ES6 draft rev 29 (6 Dec 2014) 7.3.13. */ +bool +js::SetIntegrityLevel(JSContext* cx, HandleObject obj, IntegrityLevel level) +{ + assertSameCompartment(cx, obj); + + // Steps 3-5. (Steps 1-2 are redundant assertions.) + if (!PreventExtensions(cx, obj, level)) + return false; + + // Steps 6-7. + AutoIdVector keys(cx); + if (!GetPropertyKeys(cx, obj, JSITER_HIDDEN | JSITER_OWNONLY | JSITER_SYMBOLS, &keys)) + return false; + + // Steps 8-9, loosely interpreted. + if (obj->isNative() && !obj->as<NativeObject>().inDictionaryMode() && + !obj->is<TypedArrayObject>()) + { + HandleNativeObject nobj = obj.as<NativeObject>(); + + // Seal/freeze non-dictionary objects by constructing a new shape + // hierarchy mirroring the original one, which can be shared if many + // objects with the same structure are sealed/frozen. If we use the + // generic path below then any non-empty object will be converted to + // dictionary mode. + RootedShape last(cx, EmptyShape::getInitialShape(cx, nobj->getClass(), + nobj->taggedProto(), + nobj->numFixedSlots(), + nobj->lastProperty()->getObjectFlags())); + if (!last) + return false; + + // Get an in-order list of the shapes in this object. + Rooted<ShapeVector> shapes(cx, ShapeVector(cx)); + for (Shape::Range<NoGC> r(nobj->lastProperty()); !r.empty(); r.popFront()) { + if (!shapes.append(&r.front())) + return false; + } + Reverse(shapes.begin(), shapes.end()); + + for (Shape* shape : shapes) { + Rooted<StackShape> child(cx, StackShape(shape)); + child.setAttrs(child.attrs() | GetSealedOrFrozenAttributes(child.attrs(), level)); + + if (!JSID_IS_EMPTY(child.get().propid) && level == IntegrityLevel::Frozen) + MarkTypePropertyNonWritable(cx, nobj, child.get().propid); + + last = cx->zone()->propertyTree.getChild(cx, last, child); + if (!last) + return false; + } + + MOZ_ASSERT(nobj->lastProperty()->slotSpan() == last->slotSpan()); + JS_ALWAYS_TRUE(nobj->setLastProperty(cx, last)); + + // Ordinarily ArraySetLength handles this, but we're going behind its back + // right now, so we must do this manually. + // + // ArraySetLength also implements the capacity <= length invariant for + // arrays with non-writable length. We don't need to do anything special + // for that, because capacity was zeroed out by preventExtensions. (See + // the assertion about getDenseCapacity above.) + if (level == IntegrityLevel::Frozen && obj->is<ArrayObject>()) { + if (!obj->as<ArrayObject>().maybeCopyElementsForWrite(cx)) + return false; + obj->as<ArrayObject>().getElementsHeader()->setNonwritableArrayLength(); + } + } else { + RootedId id(cx); + Rooted<PropertyDescriptor> desc(cx); + + const unsigned AllowConfigure = JSPROP_IGNORE_ENUMERATE | JSPROP_IGNORE_READONLY | + JSPROP_IGNORE_VALUE; + const unsigned AllowConfigureAndWritable = AllowConfigure & ~JSPROP_IGNORE_READONLY; + + // 8.a/9.a. The two different loops are merged here. + for (size_t i = 0; i < keys.length(); i++) { + id = keys[i]; + + if (level == IntegrityLevel::Sealed) { + // 8.a.i. + desc.setAttributes(AllowConfigure | JSPROP_PERMANENT); + } else { + // 9.a.i-ii. + Rooted<PropertyDescriptor> currentDesc(cx); + if (!GetOwnPropertyDescriptor(cx, obj, id, ¤tDesc)) + return false; + + // 9.a.iii. + if (!currentDesc.object()) + continue; + + // 9.a.iii.1-2 + if (currentDesc.isAccessorDescriptor()) + desc.setAttributes(AllowConfigure | JSPROP_PERMANENT); + else + desc.setAttributes(AllowConfigureAndWritable | JSPROP_PERMANENT | JSPROP_READONLY); + } + + // 8.a.i-ii. / 9.a.iii.3-4 + if (!DefineProperty(cx, obj, id, desc)) + return false; + } + } + + return true; +} + +// ES6 draft rev33 (12 Feb 2015) 7.3.15 +bool +js::TestIntegrityLevel(JSContext* cx, HandleObject obj, IntegrityLevel level, bool* result) +{ + // Steps 3-6. (Steps 1-2 are redundant assertions.) + bool status; + if (!IsExtensible(cx, obj, &status)) + return false; + if (status) { + *result = false; + return true; + } + + // Steps 7-8. + AutoIdVector props(cx); + if (!GetPropertyKeys(cx, obj, JSITER_HIDDEN | JSITER_OWNONLY | JSITER_SYMBOLS, &props)) + return false; + + // Step 9. + RootedId id(cx); + Rooted<PropertyDescriptor> desc(cx); + for (size_t i = 0, len = props.length(); i < len; i++) { + id = props[i]; + + // Steps 9.a-b. + if (!GetOwnPropertyDescriptor(cx, obj, id, &desc)) + return false; + + // Step 9.c. + if (!desc.object()) + continue; + + // Steps 9.c.i-ii. + if (desc.configurable() || + (level == IntegrityLevel::Frozen && desc.isDataDescriptor() && desc.writable())) + { + *result = false; + return true; + } + } + + // Step 10. + *result = true; + return true; +} + + +/* * */ + +/* + * Get the GC kind to use for scripted 'new' on the given class. + * FIXME bug 547327: estimate the size from the allocation site. + */ +static inline gc::AllocKind +NewObjectGCKind(const js::Class* clasp) +{ + if (clasp == &ArrayObject::class_) + return gc::AllocKind::OBJECT8; + if (clasp == &JSFunction::class_) + return gc::AllocKind::OBJECT2; + return gc::AllocKind::OBJECT4; +} + +static inline JSObject* +NewObject(ExclusiveContext* cx, HandleObjectGroup group, gc::AllocKind kind, + NewObjectKind newKind, uint32_t initialShapeFlags = 0) +{ + const Class* clasp = group->clasp(); + + MOZ_ASSERT(clasp != &ArrayObject::class_); + MOZ_ASSERT_IF(clasp == &JSFunction::class_, + kind == AllocKind::FUNCTION || kind == AllocKind::FUNCTION_EXTENDED); + + // For objects which can have fixed data following the object, only use + // enough fixed slots to cover the number of reserved slots in the object, + // regardless of the allocation kind specified. + size_t nfixed = ClassCanHaveFixedData(clasp) + ? GetGCKindSlots(gc::GetGCObjectKind(clasp), clasp) + : GetGCKindSlots(kind, clasp); + + RootedShape shape(cx, EmptyShape::getInitialShape(cx, clasp, group->proto(), nfixed, + initialShapeFlags)); + if (!shape) + return nullptr; + + gc::InitialHeap heap = GetInitialHeap(newKind, clasp); + JSObject* obj = JSObject::create(cx, kind, heap, shape, group); + if (!obj) + return nullptr; + + if (newKind == SingletonObject) { + RootedObject nobj(cx, obj); + if (!JSObject::setSingleton(cx, nobj)) + return nullptr; + obj = nobj; + } + + probes::CreateObject(cx, obj); + return obj; +} + +void +NewObjectCache::fillProto(EntryIndex entry, const Class* clasp, js::TaggedProto proto, + gc::AllocKind kind, NativeObject* obj) +{ + MOZ_ASSERT_IF(proto.isObject(), !proto.toObject()->is<GlobalObject>()); + MOZ_ASSERT(obj->taggedProto() == proto); + return fill(entry, clasp, proto.raw(), kind, obj); +} + +bool +js::NewObjectWithTaggedProtoIsCachable(ExclusiveContext* cxArg, Handle<TaggedProto> proto, + NewObjectKind newKind, const Class* clasp) +{ + return cxArg->isJSContext() && + proto.isObject() && + newKind == GenericObject && + clasp->isNative() && + !proto.toObject()->is<GlobalObject>(); +} + +JSObject* +js::NewObjectWithGivenTaggedProto(ExclusiveContext* cxArg, const Class* clasp, + Handle<TaggedProto> proto, + gc::AllocKind allocKind, NewObjectKind newKind, + uint32_t initialShapeFlags) +{ + if (CanBeFinalizedInBackground(allocKind, clasp)) + allocKind = GetBackgroundAllocKind(allocKind); + + bool isCachable = NewObjectWithTaggedProtoIsCachable(cxArg, proto, newKind, clasp); + if (isCachable) { + JSContext* cx = cxArg->asJSContext(); + NewObjectCache& cache = cx->caches.newObjectCache; + NewObjectCache::EntryIndex entry = -1; + if (cache.lookupProto(clasp, proto.toObject(), allocKind, &entry)) { + JSObject* obj = cache.newObjectFromHit(cx, entry, GetInitialHeap(newKind, clasp)); + if (obj) + return obj; + } + } + + RootedObjectGroup group(cxArg, ObjectGroup::defaultNewGroup(cxArg, clasp, proto, nullptr)); + if (!group) + return nullptr; + + RootedObject obj(cxArg, NewObject(cxArg, group, allocKind, newKind, initialShapeFlags)); + if (!obj) + return nullptr; + + if (isCachable && !obj->as<NativeObject>().hasDynamicSlots()) { + NewObjectCache& cache = cxArg->asJSContext()->caches.newObjectCache; + NewObjectCache::EntryIndex entry = -1; + cache.lookupProto(clasp, proto.toObject(), allocKind, &entry); + cache.fillProto(entry, clasp, proto, allocKind, &obj->as<NativeObject>()); + } + + return obj; +} + +static bool +NewObjectIsCachable(ExclusiveContext* cxArg, NewObjectKind newKind, const Class* clasp) +{ + return cxArg->isJSContext() && + newKind == GenericObject && + clasp->isNative(); +} + +JSObject* +js::NewObjectWithClassProtoCommon(ExclusiveContext* cx, const Class* clasp, HandleObject protoArg, + gc::AllocKind allocKind, NewObjectKind newKind) +{ + if (protoArg) + return NewObjectWithGivenTaggedProto(cx, clasp, AsTaggedProto(protoArg), allocKind, newKind); + + if (CanBeFinalizedInBackground(allocKind, clasp)) + allocKind = GetBackgroundAllocKind(allocKind); + + Handle<GlobalObject*> global = cx->global(); + + bool isCachable = NewObjectIsCachable(cx, newKind, clasp); + if (isCachable) { + NewObjectCache& cache = cx->asJSContext()->caches.newObjectCache; + NewObjectCache::EntryIndex entry = -1; + if (cache.lookupGlobal(clasp, global, allocKind, &entry)) { + gc::InitialHeap heap = GetInitialHeap(newKind, clasp); + JSObject* obj = cache.newObjectFromHit(cx->asJSContext(), entry, heap); + if (obj) + return obj; + } + } + + // Find the appropriate proto for clasp. Built-in classes have a cached + // proto on cx->global(); all others get %ObjectPrototype%. + JSProtoKey protoKey = JSCLASS_CACHED_PROTO_KEY(clasp); + if (protoKey == JSProto_Null) + protoKey = JSProto_Object; + + RootedObject proto(cx); + if (!GetBuiltinPrototype(cx, protoKey, &proto)) + return nullptr; + + RootedObjectGroup group(cx, ObjectGroup::defaultNewGroup(cx, clasp, AsTaggedProto(proto))); + if (!group) + return nullptr; + + JSObject* obj = NewObject(cx, group, allocKind, newKind); + if (!obj) + return nullptr; + + if (isCachable && !obj->as<NativeObject>().hasDynamicSlots()) { + NewObjectCache& cache = cx->asJSContext()->caches.newObjectCache; + NewObjectCache::EntryIndex entry = -1; + cache.lookupGlobal(clasp, global, allocKind, &entry); + cache.fillGlobal(entry, clasp, global, allocKind, + &obj->as<NativeObject>()); + } + + return obj; +} + +static bool +NewObjectWithGroupIsCachable(ExclusiveContext* cx, HandleObjectGroup group, + NewObjectKind newKind) +{ + return group->proto().isObject() && + newKind == GenericObject && + group->clasp()->isNative() && + (!group->newScript() || group->newScript()->analyzed()) && + cx->isJSContext(); +} + +/* + * Create a plain object with the specified group. This bypasses getNewGroup to + * avoid losing creation site information for objects made by scripted 'new'. + */ +JSObject* +js::NewObjectWithGroupCommon(ExclusiveContext* cx, HandleObjectGroup group, + gc::AllocKind allocKind, NewObjectKind newKind) +{ + MOZ_ASSERT(gc::IsObjectAllocKind(allocKind)); + if (CanBeFinalizedInBackground(allocKind, group->clasp())) + allocKind = GetBackgroundAllocKind(allocKind); + + bool isCachable = NewObjectWithGroupIsCachable(cx, group, newKind); + if (isCachable) { + NewObjectCache& cache = cx->asJSContext()->caches.newObjectCache; + NewObjectCache::EntryIndex entry = -1; + if (cache.lookupGroup(group, allocKind, &entry)) { + JSObject* obj = cache.newObjectFromHit(cx->asJSContext(), entry, + GetInitialHeap(newKind, group->clasp())); + if (obj) + return obj; + } + } + + JSObject* obj = NewObject(cx, group, allocKind, newKind); + if (!obj) + return nullptr; + + if (isCachable && !obj->as<NativeObject>().hasDynamicSlots()) { + NewObjectCache& cache = cx->asJSContext()->caches.newObjectCache; + NewObjectCache::EntryIndex entry = -1; + cache.lookupGroup(group, allocKind, &entry); + cache.fillGroup(entry, group, allocKind, &obj->as<NativeObject>()); + } + + return obj; +} + +bool +js::NewObjectScriptedCall(JSContext* cx, MutableHandleObject pobj) +{ + jsbytecode* pc; + RootedScript script(cx, cx->currentScript(&pc)); + gc::AllocKind allocKind = NewObjectGCKind(&PlainObject::class_); + NewObjectKind newKind = GenericObject; + if (script && ObjectGroup::useSingletonForAllocationSite(script, pc, &PlainObject::class_)) + newKind = SingletonObject; + RootedObject obj(cx, NewBuiltinClassInstance<PlainObject>(cx, allocKind, newKind)); + if (!obj) + return false; + + if (script) { + /* Try to specialize the group of the object to the scripted call site. */ + if (!ObjectGroup::setAllocationSiteObjectGroup(cx, script, pc, obj, newKind == SingletonObject)) + return false; + } + + pobj.set(obj); + return true; +} + +JSObject* +js::CreateThis(JSContext* cx, const Class* newclasp, HandleObject callee) +{ + RootedObject proto(cx); + if (!GetPrototypeFromConstructor(cx, callee, &proto)) + return nullptr; + gc::AllocKind kind = NewObjectGCKind(newclasp); + return NewObjectWithClassProto(cx, newclasp, proto, kind); +} + +static inline JSObject* +CreateThisForFunctionWithGroup(JSContext* cx, HandleObjectGroup group, + NewObjectKind newKind) +{ + if (group->maybeUnboxedLayout() && newKind != SingletonObject) + return UnboxedPlainObject::create(cx, group, newKind); + + if (TypeNewScript* newScript = group->newScript()) { + if (newScript->analyzed()) { + // The definite properties analysis has been performed for this + // group, so get the shape and alloc kind to use from the + // TypeNewScript's template. + RootedPlainObject templateObject(cx, newScript->templateObject()); + MOZ_ASSERT(templateObject->group() == group); + + RootedPlainObject res(cx, CopyInitializerObject(cx, templateObject, newKind)); + if (!res) + return nullptr; + + if (newKind == SingletonObject) { + Rooted<TaggedProto> proto(cx, TaggedProto(templateObject->staticPrototype())); + if (!res->splicePrototype(cx, &PlainObject::class_, proto)) + return nullptr; + } else { + res->setGroup(group); + } + return res; + } + + // The initial objects registered with a TypeNewScript can't be in the + // nursery. + if (newKind == GenericObject) + newKind = TenuredObject; + + // Not enough objects with this group have been created yet, so make a + // plain object and register it with the group. Use the maximum number + // of fixed slots, as is also required by the TypeNewScript. + gc::AllocKind allocKind = GuessObjectGCKind(NativeObject::MAX_FIXED_SLOTS); + PlainObject* res = NewObjectWithGroup<PlainObject>(cx, group, allocKind, newKind); + if (!res) + return nullptr; + + // Make sure group->newScript is still there. + if (newKind != SingletonObject && group->newScript()) + group->newScript()->registerNewObject(res); + + return res; + } + + gc::AllocKind allocKind = NewObjectGCKind(&PlainObject::class_); + + if (newKind == SingletonObject) { + Rooted<TaggedProto> protoRoot(cx, group->proto()); + return NewObjectWithGivenTaggedProto(cx, &PlainObject::class_, protoRoot, allocKind, newKind); + } + return NewObjectWithGroup<PlainObject>(cx, group, allocKind, newKind); +} + +JSObject* +js::CreateThisForFunctionWithProto(JSContext* cx, HandleObject callee, HandleObject newTarget, + HandleObject proto, NewObjectKind newKind /* = GenericObject */) +{ + RootedObject res(cx); + + if (proto) { + RootedObjectGroup group(cx, ObjectGroup::defaultNewGroup(cx, nullptr, TaggedProto(proto), + newTarget)); + if (!group) + return nullptr; + + if (group->newScript() && !group->newScript()->analyzed()) { + bool regenerate; + if (!group->newScript()->maybeAnalyze(cx, group, ®enerate)) + return nullptr; + if (regenerate) { + // The script was analyzed successfully and may have changed + // the new type table, so refetch the group. + group = ObjectGroup::defaultNewGroup(cx, nullptr, TaggedProto(proto), + newTarget); + MOZ_ASSERT(group && group->newScript()); + } + } + + res = CreateThisForFunctionWithGroup(cx, group, newKind); + } else { + res = NewBuiltinClassInstance<PlainObject>(cx, newKind); + } + + if (res) { + JSScript* script = callee->as<JSFunction>().getOrCreateScript(cx); + if (!script) + return nullptr; + TypeScript::SetThis(cx, script, TypeSet::ObjectType(res)); + } + + return res; +} + +bool +js::GetPrototypeFromConstructor(JSContext* cx, HandleObject newTarget, MutableHandleObject proto) +{ + RootedValue protov(cx); + if (!GetProperty(cx, newTarget, newTarget, cx->names().prototype, &protov)) + return false; + proto.set(protov.isObject() ? &protov.toObject() : nullptr); + return true; +} + +bool +js::GetPrototypeFromCallableConstructor(JSContext* cx, const CallArgs& args, MutableHandleObject proto) +{ + RootedObject newTarget(cx); + if (args.isConstructing()) + newTarget = &args.newTarget().toObject(); + else + newTarget = &args.callee(); + return GetPrototypeFromConstructor(cx, newTarget, proto); +} + +JSObject* +js::CreateThisForFunction(JSContext* cx, HandleObject callee, HandleObject newTarget, + NewObjectKind newKind) +{ + RootedObject proto(cx); + if (!GetPrototypeFromConstructor(cx, newTarget, &proto)) + return nullptr; + + JSObject* obj = CreateThisForFunctionWithProto(cx, callee, newTarget, proto, newKind); + + if (obj && newKind == SingletonObject) { + RootedPlainObject nobj(cx, &obj->as<PlainObject>()); + + /* Reshape the singleton before passing it as the 'this' value. */ + NativeObject::clear(cx, nobj); + + JSScript* calleeScript = callee->as<JSFunction>().nonLazyScript(); + TypeScript::SetThis(cx, calleeScript, TypeSet::ObjectType(nobj)); + + return nobj; + } + + return obj; +} + +/* static */ bool +JSObject::nonNativeSetProperty(JSContext* cx, HandleObject obj, HandleId id, HandleValue v, + HandleValue receiver, ObjectOpResult& result) +{ + RootedValue value(cx, v); + if (MOZ_UNLIKELY(obj->watched())) { + WatchpointMap* wpmap = cx->compartment()->watchpointMap; + if (wpmap && !wpmap->triggerWatchpoint(cx, obj, id, &value)) + return false; + } + return obj->getOpsSetProperty()(cx, obj, id, value, receiver, result); +} + +/* static */ bool +JSObject::nonNativeSetElement(JSContext* cx, HandleObject obj, uint32_t index, HandleValue v, + HandleValue receiver, ObjectOpResult& result) +{ + RootedId id(cx); + if (!IndexToId(cx, index, &id)) + return false; + return nonNativeSetProperty(cx, obj, id, v, receiver, result); +} + +JS_FRIEND_API(bool) +JS_CopyPropertyFrom(JSContext* cx, HandleId id, HandleObject target, + HandleObject obj, PropertyCopyBehavior copyBehavior) +{ + // |obj| and |cx| are generally not same-compartment with |target| here. + assertSameCompartment(cx, obj, id); + Rooted<PropertyDescriptor> desc(cx); + + if (!GetOwnPropertyDescriptor(cx, obj, id, &desc)) + return false; + MOZ_ASSERT(desc.object()); + + // Silently skip JSGetterOp/JSSetterOp-implemented accessors. + if (desc.getter() && !desc.hasGetterObject()) + return true; + if (desc.setter() && !desc.hasSetterObject()) + return true; + + if (copyBehavior == MakeNonConfigurableIntoConfigurable) { + // Mask off the JSPROP_PERMANENT bit. + desc.attributesRef() &= ~JSPROP_PERMANENT; + } + + JSAutoCompartment ac(cx, target); + RootedId wrappedId(cx, id); + if (!cx->compartment()->wrap(cx, &desc)) + return false; + + return DefineProperty(cx, target, wrappedId, desc); +} + +JS_FRIEND_API(bool) +JS_CopyPropertiesFrom(JSContext* cx, HandleObject target, HandleObject obj) +{ + JSAutoCompartment ac(cx, obj); + + AutoIdVector props(cx); + if (!GetPropertyKeys(cx, obj, JSITER_OWNONLY | JSITER_HIDDEN | JSITER_SYMBOLS, &props)) + return false; + + for (size_t i = 0; i < props.length(); ++i) { + if (!JS_CopyPropertyFrom(cx, props[i], target, obj)) + return false; + } + + return true; +} + +static bool +CopyProxyObject(JSContext* cx, Handle<ProxyObject*> from, Handle<ProxyObject*> to) +{ + MOZ_ASSERT(from->getClass() == to->getClass()); + + if (from->is<WrapperObject>() && + (Wrapper::wrapperHandler(from)->flags() & + Wrapper::CROSS_COMPARTMENT)) + { + to->setCrossCompartmentPrivate(GetProxyPrivate(from)); + } else { + RootedValue v(cx, GetProxyPrivate(from)); + if (!cx->compartment()->wrap(cx, &v)) + return false; + to->setSameCompartmentPrivate(v); + } + + RootedValue v(cx); + for (size_t n = 0; n < js::detail::PROXY_EXTRA_SLOTS; n++) { + v = GetProxyExtra(from, n); + if (!cx->compartment()->wrap(cx, &v)) + return false; + SetProxyExtra(to, n, v); + } + + return true; +} + +JSObject* +js::CloneObject(JSContext* cx, HandleObject obj, Handle<js::TaggedProto> proto) +{ + if (!obj->isNative() && !obj->is<ProxyObject>()) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_CLONE_OBJECT); + return nullptr; + } + + RootedObject clone(cx); + if (obj->isNative()) { + clone = NewObjectWithGivenTaggedProto(cx, obj->getClass(), proto); + if (!clone) + return nullptr; + + if (clone->is<JSFunction>() && (obj->compartment() != clone->compartment())) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_CLONE_OBJECT); + return nullptr; + } + + if (obj->as<NativeObject>().hasPrivate()) + clone->as<NativeObject>().setPrivate(obj->as<NativeObject>().getPrivate()); + } else { + ProxyOptions options; + options.setClass(obj->getClass()); + + clone = ProxyObject::New(cx, GetProxyHandler(obj), JS::NullHandleValue, proto, options); + if (!clone) + return nullptr; + + if (!CopyProxyObject(cx, obj.as<ProxyObject>(), clone.as<ProxyObject>())) + return nullptr; + } + + return clone; +} + +static bool +GetScriptArrayObjectElements(JSContext* cx, HandleObject obj, MutableHandle<GCVector<Value>> values) +{ + MOZ_ASSERT(!obj->isSingleton()); + MOZ_ASSERT(obj->is<ArrayObject>() || obj->is<UnboxedArrayObject>()); + MOZ_ASSERT(!obj->isIndexed()); + + size_t length = GetAnyBoxedOrUnboxedArrayLength(obj); + if (!values.appendN(MagicValue(JS_ELEMENTS_HOLE), length)) + return false; + + size_t initlen = GetAnyBoxedOrUnboxedInitializedLength(obj); + for (size_t i = 0; i < initlen; i++) + values[i].set(GetAnyBoxedOrUnboxedDenseElement(obj, i)); + + return true; +} + +static bool +GetScriptPlainObjectProperties(JSContext* cx, HandleObject obj, + MutableHandle<IdValueVector> properties) +{ + if (obj->is<PlainObject>()) { + PlainObject* nobj = &obj->as<PlainObject>(); + + if (!properties.appendN(IdValuePair(), nobj->slotSpan())) + return false; + + for (Shape::Range<NoGC> r(nobj->lastProperty()); !r.empty(); r.popFront()) { + Shape& shape = r.front(); + MOZ_ASSERT(shape.isDataDescriptor()); + uint32_t slot = shape.slot(); + properties[slot].get().id = shape.propid(); + properties[slot].get().value = nobj->getSlot(slot); + } + + for (size_t i = 0; i < nobj->getDenseInitializedLength(); i++) { + Value v = nobj->getDenseElement(i); + if (!v.isMagic(JS_ELEMENTS_HOLE) && !properties.append(IdValuePair(INT_TO_JSID(i), v))) + return false; + } + + return true; + } + + if (obj->is<UnboxedPlainObject>()) { + UnboxedPlainObject* nobj = &obj->as<UnboxedPlainObject>(); + + const UnboxedLayout& layout = nobj->layout(); + if (!properties.appendN(IdValuePair(), layout.properties().length())) + return false; + + for (size_t i = 0; i < layout.properties().length(); i++) { + const UnboxedLayout::Property& property = layout.properties()[i]; + properties[i].get().id = NameToId(property.name); + properties[i].get().value = nobj->getValue(property); + } + + return true; + } + + MOZ_CRASH("Bad object kind"); +} + +static bool +DeepCloneValue(JSContext* cx, Value* vp, NewObjectKind newKind) +{ + if (vp->isObject()) { + RootedObject obj(cx, &vp->toObject()); + obj = DeepCloneObjectLiteral(cx, obj, newKind); + if (!obj) + return false; + vp->setObject(*obj); + } + return true; +} + +JSObject* +js::DeepCloneObjectLiteral(JSContext* cx, HandleObject obj, NewObjectKind newKind) +{ + /* NB: Keep this in sync with XDRObjectLiteral. */ + MOZ_ASSERT_IF(obj->isSingleton(), + cx->compartment()->behaviors().getSingletonsAsTemplates()); + MOZ_ASSERT(obj->is<PlainObject>() || obj->is<UnboxedPlainObject>() || + obj->is<ArrayObject>() || obj->is<UnboxedArrayObject>()); + MOZ_ASSERT(newKind != SingletonObject); + + if (obj->is<ArrayObject>() || obj->is<UnboxedArrayObject>()) { + Rooted<GCVector<Value>> values(cx, GCVector<Value>(cx)); + if (!GetScriptArrayObjectElements(cx, obj, &values)) + return nullptr; + + // Deep clone any elements. + for (uint32_t i = 0; i < values.length(); ++i) { + if (!DeepCloneValue(cx, values[i].address(), newKind)) + return nullptr; + } + + ObjectGroup::NewArrayKind arrayKind = ObjectGroup::NewArrayKind::Normal; + if (obj->is<ArrayObject>() && obj->as<ArrayObject>().denseElementsAreCopyOnWrite()) + arrayKind = ObjectGroup::NewArrayKind::CopyOnWrite; + + return ObjectGroup::newArrayObject(cx, values.begin(), values.length(), newKind, + arrayKind); + } + + Rooted<IdValueVector> properties(cx, IdValueVector(cx)); + if (!GetScriptPlainObjectProperties(cx, obj, &properties)) + return nullptr; + + for (size_t i = 0; i < properties.length(); i++) { + if (!DeepCloneValue(cx, &properties[i].get().value, newKind)) + return nullptr; + } + + if (obj->isSingleton()) + newKind = SingletonObject; + + return ObjectGroup::newPlainObject(cx, properties.begin(), properties.length(), newKind); +} + +static bool +InitializePropertiesFromCompatibleNativeObject(JSContext* cx, + HandleNativeObject dst, + HandleNativeObject src) +{ + assertSameCompartment(cx, src, dst); + MOZ_ASSERT(src->getClass() == dst->getClass()); + MOZ_ASSERT(dst->lastProperty()->getObjectFlags() == 0); + MOZ_ASSERT(!src->isSingleton()); + MOZ_ASSERT(src->numFixedSlots() == dst->numFixedSlots()); + + if (!dst->ensureElements(cx, src->getDenseInitializedLength())) + return false; + + uint32_t initialized = src->getDenseInitializedLength(); + for (uint32_t i = 0; i < initialized; ++i) { + dst->setDenseInitializedLength(i + 1); + dst->initDenseElement(i, src->getDenseElement(i)); + } + + MOZ_ASSERT(!src->hasPrivate()); + RootedShape shape(cx); + if (src->staticPrototype() == dst->staticPrototype()) { + shape = src->lastProperty(); + } else { + // We need to generate a new shape for dst that has dst's proto but all + // the property information from src. Note that we asserted above that + // dst's object flags are 0. + shape = EmptyShape::getInitialShape(cx, dst->getClass(), dst->taggedProto(), + dst->numFixedSlots(), 0); + if (!shape) + return false; + + // Get an in-order list of the shapes in the src object. + Rooted<ShapeVector> shapes(cx, ShapeVector(cx)); + for (Shape::Range<NoGC> r(src->lastProperty()); !r.empty(); r.popFront()) { + if (!shapes.append(&r.front())) + return false; + } + Reverse(shapes.begin(), shapes.end()); + + for (Shape* shape : shapes) { + Rooted<StackShape> child(cx, StackShape(shape)); + shape = cx->zone()->propertyTree.getChild(cx, shape, child); + if (!shape) + return false; + } + } + size_t span = shape->slotSpan(); + if (!dst->setLastProperty(cx, shape)) + return false; + for (size_t i = JSCLASS_RESERVED_SLOTS(src->getClass()); i < span; i++) + dst->setSlot(i, src->getSlot(i)); + + return true; +} + +JS_FRIEND_API(bool) +JS_InitializePropertiesFromCompatibleNativeObject(JSContext* cx, + HandleObject dst, + HandleObject src) +{ + return InitializePropertiesFromCompatibleNativeObject(cx, + dst.as<NativeObject>(), + src.as<NativeObject>()); +} + +template<XDRMode mode> +bool +js::XDRObjectLiteral(XDRState<mode>* xdr, MutableHandleObject obj) +{ + /* NB: Keep this in sync with DeepCloneObjectLiteral. */ + + JSContext* cx = xdr->cx(); + MOZ_ASSERT_IF(mode == XDR_ENCODE && obj->isSingleton(), + cx->compartment()->behaviors().getSingletonsAsTemplates()); + + // Distinguish between objects and array classes. + uint32_t isArray = 0; + { + if (mode == XDR_ENCODE) { + MOZ_ASSERT(obj->is<PlainObject>() || + obj->is<UnboxedPlainObject>() || + obj->is<ArrayObject>() || + obj->is<UnboxedArrayObject>()); + isArray = (obj->is<ArrayObject>() || obj->is<UnboxedArrayObject>()) ? 1 : 0; + } + + if (!xdr->codeUint32(&isArray)) + return false; + } + + RootedValue tmpValue(cx), tmpIdValue(cx); + RootedId tmpId(cx); + + if (isArray) { + Rooted<GCVector<Value>> values(cx, GCVector<Value>(cx)); + if (mode == XDR_ENCODE && !GetScriptArrayObjectElements(cx, obj, &values)) + return false; + + uint32_t initialized; + if (mode == XDR_ENCODE) + initialized = values.length(); + if (!xdr->codeUint32(&initialized)) + return false; + if (mode == XDR_DECODE && !values.appendN(MagicValue(JS_ELEMENTS_HOLE), initialized)) + return false; + + // Recursively copy dense elements. + for (unsigned i = 0; i < initialized; i++) { + if (!xdr->codeConstValue(values[i])) + return false; + } + + uint32_t copyOnWrite; + if (mode == XDR_ENCODE) + copyOnWrite = obj->is<ArrayObject>() && + obj->as<ArrayObject>().denseElementsAreCopyOnWrite(); + if (!xdr->codeUint32(©OnWrite)) + return false; + + if (mode == XDR_DECODE) { + ObjectGroup::NewArrayKind arrayKind = copyOnWrite + ? ObjectGroup::NewArrayKind::CopyOnWrite + : ObjectGroup::NewArrayKind::Normal; + obj.set(ObjectGroup::newArrayObject(cx, values.begin(), values.length(), + TenuredObject, arrayKind)); + if (!obj) + return false; + } + + return true; + } + + // Code the properties in the object. + Rooted<IdValueVector> properties(cx, IdValueVector(cx)); + if (mode == XDR_ENCODE && !GetScriptPlainObjectProperties(cx, obj, &properties)) + return false; + + uint32_t nproperties = properties.length(); + if (!xdr->codeUint32(&nproperties)) + return false; + + if (mode == XDR_DECODE && !properties.appendN(IdValuePair(), nproperties)) + return false; + + for (size_t i = 0; i < nproperties; i++) { + if (mode == XDR_ENCODE) { + tmpIdValue = IdToValue(properties[i].get().id); + tmpValue = properties[i].get().value; + } + + if (!xdr->codeConstValue(&tmpIdValue) || !xdr->codeConstValue(&tmpValue)) + return false; + + if (mode == XDR_DECODE) { + if (!ValueToId<CanGC>(cx, tmpIdValue, &tmpId)) + return false; + properties[i].get().id = tmpId; + properties[i].get().value = tmpValue; + } + } + + // Code whether the object is a singleton. + uint32_t isSingleton; + if (mode == XDR_ENCODE) + isSingleton = obj->isSingleton() ? 1 : 0; + if (!xdr->codeUint32(&isSingleton)) + return false; + + if (mode == XDR_DECODE) { + NewObjectKind newKind = isSingleton ? SingletonObject : TenuredObject; + obj.set(ObjectGroup::newPlainObject(cx, properties.begin(), properties.length(), newKind)); + if (!obj) + return false; + } + + return true; +} + +template bool +js::XDRObjectLiteral(XDRState<XDR_ENCODE>* xdr, MutableHandleObject obj); + +template bool +js::XDRObjectLiteral(XDRState<XDR_DECODE>* xdr, MutableHandleObject obj); + +bool +NativeObject::fillInAfterSwap(JSContext* cx, const Vector<Value>& values, void* priv) +{ + // This object has just been swapped with some other object, and its shape + // no longer reflects its allocated size. Correct this information and + // fill the slots in with the specified values. + MOZ_ASSERT(slotSpan() == values.length()); + + // Make sure the shape's numFixedSlots() is correct. + size_t nfixed = gc::GetGCKindSlots(asTenured().getAllocKind(), getClass()); + if (nfixed != shape_->numFixedSlots()) { + if (!generateOwnShape(cx)) + return false; + shape_->setNumFixedSlots(nfixed); + } + + if (hasPrivate()) + setPrivate(priv); + else + MOZ_ASSERT(!priv); + + if (slots_) { + js_free(slots_); + slots_ = nullptr; + } + + if (size_t ndynamic = dynamicSlotsCount(nfixed, values.length(), getClass())) { + slots_ = cx->zone()->pod_malloc<HeapSlot>(ndynamic); + if (!slots_) + return false; + Debug_SetSlotRangeToCrashOnTouch(slots_, ndynamic); + } + + initSlotRange(0, values.begin(), values.length()); + return true; +} + +void +JSObject::fixDictionaryShapeAfterSwap() +{ + // Dictionary shapes can point back to their containing objects, so after + // swapping the guts of those objects fix the pointers up. + if (isNative() && as<NativeObject>().inDictionaryMode()) + as<NativeObject>().shape_->listp = &as<NativeObject>().shape_; +} + +/* Use this method with extreme caution. It trades the guts of two objects. */ +bool +JSObject::swap(JSContext* cx, HandleObject a, HandleObject b) +{ + // Ensure swap doesn't cause a finalizer to not be run. + MOZ_ASSERT(IsBackgroundFinalized(a->asTenured().getAllocKind()) == + IsBackgroundFinalized(b->asTenured().getAllocKind())); + MOZ_ASSERT(a->compartment() == b->compartment()); + + AutoEnterOOMUnsafeRegion oomUnsafe; + + AutoCompartment ac(cx, a); + + if (!a->getGroup(cx)) + oomUnsafe.crash("JSObject::swap"); + if (!b->getGroup(cx)) + oomUnsafe.crash("JSObject::swap"); + + /* + * Neither object may be in the nursery, but ensure we update any embedded + * nursery pointers in either object. + */ + MOZ_ASSERT(!IsInsideNursery(a) && !IsInsideNursery(b)); + cx->runtime()->gc.storeBuffer.putWholeCell(a); + cx->runtime()->gc.storeBuffer.putWholeCell(b); + + unsigned r = NotifyGCPreSwap(a, b); + + // Do the fundamental swapping of the contents of two objects. + MOZ_ASSERT(a->compartment() == b->compartment()); + MOZ_ASSERT(a->is<JSFunction>() == b->is<JSFunction>()); + + // Don't try to swap functions with different sizes. + MOZ_ASSERT_IF(a->is<JSFunction>(), a->tenuredSizeOfThis() == b->tenuredSizeOfThis()); + + // Watch for oddball objects that have special organizational issues and + // can't be swapped. + MOZ_ASSERT(!a->is<RegExpObject>() && !b->is<RegExpObject>()); + MOZ_ASSERT(!a->is<ArrayObject>() && !b->is<ArrayObject>()); + MOZ_ASSERT(!a->is<ArrayBufferObject>() && !b->is<ArrayBufferObject>()); + MOZ_ASSERT(!a->is<TypedArrayObject>() && !b->is<TypedArrayObject>()); + MOZ_ASSERT(!a->is<TypedObject>() && !b->is<TypedObject>()); + + if (a->tenuredSizeOfThis() == b->tenuredSizeOfThis()) { + // When both objects are the same size, just do a plain swap of their + // contents. + size_t size = a->tenuredSizeOfThis(); + + char tmp[mozilla::tl::Max<sizeof(JSFunction), sizeof(JSObject_Slots16)>::value]; + MOZ_ASSERT(size <= sizeof(tmp)); + + js_memcpy(tmp, a, size); + js_memcpy(a, b, size); + js_memcpy(b, tmp, size); + + a->fixDictionaryShapeAfterSwap(); + b->fixDictionaryShapeAfterSwap(); + } else { + // Avoid GC in here to avoid confusing the tracing code with our + // intermediate state. + AutoSuppressGC suppress(cx); + + // When the objects have different sizes, they will have different + // numbers of fixed slots before and after the swap, so the slots for + // native objects will need to be rearranged. + NativeObject* na = a->isNative() ? &a->as<NativeObject>() : nullptr; + NativeObject* nb = b->isNative() ? &b->as<NativeObject>() : nullptr; + + // Remember the original values from the objects. + Vector<Value> avals(cx); + void* apriv = nullptr; + if (na) { + apriv = na->hasPrivate() ? na->getPrivate() : nullptr; + for (size_t i = 0; i < na->slotSpan(); i++) { + if (!avals.append(na->getSlot(i))) + oomUnsafe.crash("JSObject::swap"); + } + } + Vector<Value> bvals(cx); + void* bpriv = nullptr; + if (nb) { + bpriv = nb->hasPrivate() ? nb->getPrivate() : nullptr; + for (size_t i = 0; i < nb->slotSpan(); i++) { + if (!bvals.append(nb->getSlot(i))) + oomUnsafe.crash("JSObject::swap"); + } + } + + // Swap the main fields of the objects, whether they are native objects or proxies. + char tmp[sizeof(JSObject_Slots0)]; + js_memcpy(&tmp, a, sizeof tmp); + js_memcpy(a, b, sizeof tmp); + js_memcpy(b, &tmp, sizeof tmp); + + a->fixDictionaryShapeAfterSwap(); + b->fixDictionaryShapeAfterSwap(); + + if (na && !b->as<NativeObject>().fillInAfterSwap(cx, avals, apriv)) + oomUnsafe.crash("fillInAfterSwap"); + if (nb && !a->as<NativeObject>().fillInAfterSwap(cx, bvals, bpriv)) + oomUnsafe.crash("fillInAfterSwap"); + } + + // Swapping the contents of two objects invalidates type sets which contain + // either of the objects, so mark all such sets as unknown. + MarkObjectGroupUnknownProperties(cx, a->group()); + MarkObjectGroupUnknownProperties(cx, b->group()); + + /* + * We need a write barrier here. If |a| was marked and |b| was not, then + * after the swap, |b|'s guts would never be marked. The write barrier + * solves this. + * + * Normally write barriers happen before the write. However, that's not + * necessary here because nothing is being destroyed. We're just swapping. + */ + JS::Zone* zone = a->zone(); + if (zone->needsIncrementalBarrier()) { + a->traceChildren(zone->barrierTracer()); + b->traceChildren(zone->barrierTracer()); + } + + NotifyGCPostSwap(a, b, r); + return true; +} + +static bool +DefineStandardSlot(JSContext* cx, HandleObject obj, JSProtoKey key, JSAtom* atom, + HandleValue v, uint32_t attrs, bool& named) +{ + RootedId id(cx, AtomToId(atom)); + named = DefineProperty(cx, obj, id, v, nullptr, nullptr, attrs); + return named; +} + +static void +SetClassObject(JSObject* obj, JSProtoKey key, JSObject* cobj, JSObject* proto) +{ + if (!obj->is<GlobalObject>()) + return; + + obj->as<GlobalObject>().setConstructor(key, ObjectOrNullValue(cobj)); + obj->as<GlobalObject>().setPrototype(key, ObjectOrNullValue(proto)); +} + +static void +ClearClassObject(JSObject* obj, JSProtoKey key) +{ + if (!obj->is<GlobalObject>()) + return; + + obj->as<GlobalObject>().setConstructor(key, UndefinedValue()); + obj->as<GlobalObject>().setPrototype(key, UndefinedValue()); +} + +static NativeObject* +DefineConstructorAndPrototype(JSContext* cx, HandleObject obj, JSProtoKey key, HandleAtom atom, + HandleObject protoProto, const Class* clasp, + Native constructor, unsigned nargs, + const JSPropertySpec* ps, const JSFunctionSpec* fs, + const JSPropertySpec* static_ps, const JSFunctionSpec* static_fs, + NativeObject** ctorp, AllocKind ctorKind) +{ + /* + * Create a prototype object for this class. + * + * FIXME: lazy standard (built-in) class initialization and even older + * eager boostrapping code rely on all of these properties: + * + * 1. NewObject attempting to compute a default prototype object when + * passed null for proto; and + * + * 2. NewObject tolerating no default prototype (null proto slot value) + * due to this js::InitClass call coming from js::InitFunctionClass on an + * otherwise-uninitialized global. + * + * 3. NewObject allocating a JSFunction-sized GC-thing when clasp is + * &JSFunction::class_, not a JSObject-sized (smaller) GC-thing. + * + * The JS_NewObjectForGivenProto and JS_NewObject APIs also allow clasp to + * be &JSFunction::class_ (we could break compatibility easily). But + * fixing (3) is not enough without addressing the bootstrapping dependency + * on (1) and (2). + */ + + /* + * Create the prototype object. (GlobalObject::createBlankPrototype isn't + * used because it won't let us use protoProto as the proto. + */ + RootedNativeObject proto(cx, NewNativeObjectWithClassProto(cx, clasp, protoProto, SingletonObject)); + if (!proto) + return nullptr; + + /* After this point, control must exit via label bad or out. */ + RootedNativeObject ctor(cx); + bool named = false; + bool cached = false; + if (!constructor) { + /* + * Lacking a constructor, name the prototype (e.g., Math) unless this + * class (a) is anonymous, i.e. for internal use only; (b) the class + * of obj (the global object) is has a reserved slot indexed by key; + * and (c) key is not the null key. + */ + if (!(clasp->flags & JSCLASS_IS_ANONYMOUS) || !obj->is<GlobalObject>() || + key == JSProto_Null) + { + uint32_t attrs = (clasp->flags & JSCLASS_IS_ANONYMOUS) + ? JSPROP_READONLY | JSPROP_PERMANENT + : 0; + RootedValue value(cx, ObjectValue(*proto)); + if (!DefineStandardSlot(cx, obj, key, atom, value, attrs, named)) + goto bad; + } + + ctor = proto; + } else { + RootedFunction fun(cx, NewNativeConstructor(cx, constructor, nargs, atom, ctorKind)); + if (!fun) + goto bad; + + /* + * Set the class object early for standard class constructors. Type + * inference may need to access these, and js::GetBuiltinPrototype will + * fail if it tries to do a reentrant reconstruction of the class. + */ + if (key != JSProto_Null) { + SetClassObject(obj, key, fun, proto); + cached = true; + } + + RootedValue value(cx, ObjectValue(*fun)); + if (!DefineStandardSlot(cx, obj, key, atom, value, 0, named)) + goto bad; + + /* + * Optionally construct the prototype object, before the class has + * been fully initialized. Allow the ctor to replace proto with a + * different object, as is done for operator new. + */ + ctor = fun; + if (!LinkConstructorAndPrototype(cx, ctor, proto)) + goto bad; + + /* Bootstrap Function.prototype (see also JS_InitStandardClasses). */ + Rooted<TaggedProto> tagged(cx, TaggedProto(proto)); + if (ctor->getClass() == clasp && !ctor->splicePrototype(cx, clasp, tagged)) + goto bad; + } + + if (!DefinePropertiesAndFunctions(cx, proto, ps, fs) || + (ctor != proto && !DefinePropertiesAndFunctions(cx, ctor, static_ps, static_fs))) + { + goto bad; + } + + /* If this is a standard class, cache its prototype. */ + if (!cached && key != JSProto_Null) + SetClassObject(obj, key, ctor, proto); + + if (ctorp) + *ctorp = ctor; + return proto; + +bad: + if (named) { + ObjectOpResult ignored; + RootedId id(cx, AtomToId(atom)); + + // XXX FIXME - absurd to call this here; instead define the property last. + DeleteProperty(cx, obj, id, ignored); + } + if (cached) + ClearClassObject(obj, key); + return nullptr; +} + +NativeObject* +js::InitClass(JSContext* cx, HandleObject obj, HandleObject protoProto_, + const Class* clasp, Native constructor, unsigned nargs, + const JSPropertySpec* ps, const JSFunctionSpec* fs, + const JSPropertySpec* static_ps, const JSFunctionSpec* static_fs, + NativeObject** ctorp, AllocKind ctorKind) +{ + RootedObject protoProto(cx, protoProto_); + + /* Check function pointer members. */ + MOZ_ASSERT(clasp->getGetProperty() != JS_PropertyStub); + MOZ_ASSERT(clasp->getSetProperty() != JS_StrictPropertyStub); + + RootedAtom atom(cx, Atomize(cx, clasp->name, strlen(clasp->name))); + if (!atom) + return nullptr; + + /* + * All instances of the class will inherit properties from the prototype + * object we are about to create (in DefineConstructorAndPrototype), which + * in turn will inherit from protoProto. + * + * When initializing a standard class (other than Object), if protoProto is + * null, default to Object.prototype. The engine's internal uses of + * js::InitClass depend on this nicety. + */ + JSProtoKey key = JSCLASS_CACHED_PROTO_KEY(clasp); + if (key != JSProto_Null && + !protoProto && + !GetBuiltinPrototype(cx, JSProto_Object, &protoProto)) + { + return nullptr; + } + + return DefineConstructorAndPrototype(cx, obj, key, atom, protoProto, clasp, constructor, nargs, + ps, fs, static_ps, static_fs, ctorp, ctorKind); +} + +void +JSObject::fixupAfterMovingGC() +{ + // For copy-on-write objects that don't own their elements, fix up the + // elements pointer if it points to inline elements in the owning object. + if (is<NativeObject>()) { + NativeObject& obj = as<NativeObject>(); + if (obj.denseElementsAreCopyOnWrite()) { + NativeObject* owner = obj.getElementsHeader()->ownerObject(); + // Get the new owner pointer but don't call MaybeForwarded as we + // don't need to access the object's shape. + if (IsForwarded(owner)) + owner = Forwarded(owner); + if (owner != &obj && owner->hasFixedElements()) + obj.elements_ = owner->getElementsHeader()->elements(); + MOZ_ASSERT(!IsForwarded(obj.getElementsHeader()->ownerObject().get())); + } + } +} + +bool +js::SetClassAndProto(JSContext* cx, HandleObject obj, + const Class* clasp, Handle<js::TaggedProto> proto) +{ + // Regenerate the object's shape. If the object is a proto (isDelegate()), + // we also need to regenerate shapes for all of the objects along the old + // prototype chain, in case any entries were filled by looking up through + // obj. Stop when a non-native object is found, prototype lookups will not + // be cached across these. + // + // How this shape change is done is very delicate; the change can be made + // either by marking the object's prototype as uncacheable (such that the + // JIT'ed ICs cannot assume the shape determines the prototype) or by just + // generating a new shape for the object. Choosing the former is bad if the + // object is on the prototype chain of other objects, as the uncacheable + // prototype can inhibit iterator caches on those objects and slow down + // prototype accesses. Choosing the latter is bad if there are many similar + // objects to this one which will have their prototype mutated, as the + // generateOwnShape forces the object into dictionary mode and similar + // property lineages will be repeatedly cloned. + // + // :XXX: bug 707717 make this code less brittle. + RootedObject oldproto(cx, obj); + while (oldproto && oldproto->isNative()) { + if (oldproto->isSingleton()) { + // We always generate a new shape if the object is a singleton, + // regardless of the uncacheable-proto flag. ICs may rely on + // this. + if (!oldproto->as<NativeObject>().generateOwnShape(cx)) + return false; + } else { + if (!oldproto->setUncacheableProto(cx)) + return false; + } + if (!obj->isDelegate()) { + // If |obj| is not a proto of another object, we don't need to + // reshape the whole proto chain. + MOZ_ASSERT(obj == oldproto); + break; + } + oldproto = oldproto->staticPrototype(); + } + + if (proto.isObject() && !proto.toObject()->setDelegate(cx)) + return false; + + if (obj->isSingleton()) { + /* + * Just splice the prototype, but mark the properties as unknown for + * consistent behavior. + */ + if (!obj->splicePrototype(cx, clasp, proto)) + return false; + MarkObjectGroupUnknownProperties(cx, obj->group()); + return true; + } + + if (proto.isObject()) { + RootedObject protoObj(cx, proto.toObject()); + if (!JSObject::setNewGroupUnknown(cx, clasp, protoObj)) + return false; + } + + ObjectGroup* group = ObjectGroup::defaultNewGroup(cx, clasp, proto); + if (!group) + return false; + + /* + * Setting __proto__ on an object that has escaped and may be referenced by + * other heap objects can only be done if the properties of both objects + * are unknown. Type sets containing this object will contain the original + * type but not the new type of the object, so we need to treat all such + * type sets as unknown. + */ + MarkObjectGroupUnknownProperties(cx, obj->group()); + MarkObjectGroupUnknownProperties(cx, group); + + obj->setGroup(group); + + return true; +} + +/* static */ bool +JSObject::changeToSingleton(JSContext* cx, HandleObject obj) +{ + MOZ_ASSERT(!obj->isSingleton()); + + MarkObjectGroupUnknownProperties(cx, obj->group()); + + ObjectGroup* group = ObjectGroup::lazySingletonGroup(cx, obj->getClass(), + obj->taggedProto()); + if (!group) + return false; + + obj->group_ = group; + return true; +} + +static bool +MaybeResolveConstructor(ExclusiveContext* cxArg, Handle<GlobalObject*> global, JSProtoKey key) +{ + if (global->isStandardClassResolved(key)) + return true; + if (!cxArg->shouldBeJSContext()) + return false; + + JSContext* cx = cxArg->asJSContext(); + return GlobalObject::resolveConstructor(cx, global, key); +} + +bool +js::GetBuiltinConstructor(ExclusiveContext* cx, JSProtoKey key, MutableHandleObject objp) +{ + MOZ_ASSERT(key != JSProto_Null); + Rooted<GlobalObject*> global(cx, cx->global()); + if (!MaybeResolveConstructor(cx, global, key)) + return false; + + objp.set(&global->getConstructor(key).toObject()); + return true; +} + +bool +js::GetBuiltinPrototype(ExclusiveContext* cx, JSProtoKey key, MutableHandleObject protop) +{ + MOZ_ASSERT(key != JSProto_Null); + Rooted<GlobalObject*> global(cx, cx->global()); + if (!MaybeResolveConstructor(cx, global, key)) + return false; + + protop.set(&global->getPrototype(key).toObject()); + return true; +} + +bool +js::IsStandardPrototype(JSObject* obj, JSProtoKey key) +{ + GlobalObject& global = obj->global(); + Value v = global.getPrototype(key); + return v.isObject() && obj == &v.toObject(); +} + + +/** + * Returns the original Object.prototype from the embedding-provided incumbent + * global. + * + * Really, we want the incumbent global itself so we can pass it to other + * embedding hooks which need it. Specifically, the enqueue promise hook + * takes an incumbent global so it can set that on the PromiseCallbackJob + * it creates. + * + * The reason for not just returning the global itself is that we'd need to + * wrap it into the current compartment, and later unwrap it. Unwrapping + * globals is tricky, though: we might accidentally unwrap through an inner + * to its outer window and end up with the wrong global. Plain objects don't + * have this problem, so we use the global's Object.prototype. The code using + * it - e.g. EnqueuePromiseReactionJob - can then unwrap the object and get + * its global without fear of unwrapping too far. + */ +bool +js::GetObjectFromIncumbentGlobal(JSContext* cx, MutableHandleObject obj) +{ + RootedObject globalObj(cx, cx->runtime()->getIncumbentGlobal(cx)); + if (!globalObj) { + obj.set(nullptr); + return true; + } + + { + AutoCompartment ac(cx, globalObj); + obj.set(globalObj->as<GlobalObject>().getOrCreateObjectPrototype(cx)); + if (!obj) + return false; + } + + // The object might be from a different compartment, so wrap it. + if (obj && !cx->compartment()->wrap(cx, obj)) + return false; + + return true; +} + +JSProtoKey +JS::IdentifyStandardInstance(JSObject* obj) +{ + // Note: The prototype shares its JSClass with instances. + MOZ_ASSERT(!obj->is<CrossCompartmentWrapperObject>()); + JSProtoKey key = StandardProtoKeyOrNull(obj); + if (key != JSProto_Null && !IsStandardPrototype(obj, key)) + return key; + return JSProto_Null; +} + +JSProtoKey +JS::IdentifyStandardPrototype(JSObject* obj) +{ + // Note: The prototype shares its JSClass with instances. + MOZ_ASSERT(!obj->is<CrossCompartmentWrapperObject>()); + JSProtoKey key = StandardProtoKeyOrNull(obj); + if (key != JSProto_Null && IsStandardPrototype(obj, key)) + return key; + return JSProto_Null; +} + +JSProtoKey +JS::IdentifyStandardInstanceOrPrototype(JSObject* obj) +{ + return StandardProtoKeyOrNull(obj); +} + +JSProtoKey +JS::IdentifyStandardConstructor(JSObject* obj) +{ + // Note that NATIVE_CTOR does not imply that we are a standard constructor, + // but the converse is true (at least until we start having self-hosted + // constructors for standard classes). This lets us avoid a costly loop for + // many functions (which, depending on the call site, may be the common case). + if (!obj->is<JSFunction>() || !(obj->as<JSFunction>().flags() & JSFunction::NATIVE_CTOR)) + return JSProto_Null; + + GlobalObject& global = obj->global(); + for (size_t k = 0; k < JSProto_LIMIT; ++k) { + JSProtoKey key = static_cast<JSProtoKey>(k); + if (global.getConstructor(key) == ObjectValue(*obj)) + return key; + } + + return JSProto_Null; +} + +bool +JSObject::isCallable() const +{ + if (is<JSFunction>()) + return true; + return callHook() != nullptr; +} + +bool +JSObject::isConstructor() const +{ + if (is<JSFunction>()) { + const JSFunction& fun = as<JSFunction>(); + return fun.isConstructor(); + } + return constructHook() != nullptr; +} + +JSNative +JSObject::callHook() const +{ + const js::Class* clasp = getClass(); + + if (JSNative call = clasp->getCall()) + return call; + + if (is<js::ProxyObject>()) { + const js::ProxyObject& p = as<js::ProxyObject>(); + if (p.handler()->isCallable(const_cast<JSObject*>(this))) + return js::proxy_Call; + } + return nullptr; +} + +JSNative +JSObject::constructHook() const +{ + const js::Class* clasp = getClass(); + + if (JSNative construct = clasp->getConstruct()) + return construct; + + if (is<js::ProxyObject>()) { + const js::ProxyObject& p = as<js::ProxyObject>(); + if (p.handler()->isConstructor(const_cast<JSObject*>(this))) + return js::proxy_Construct; + } + return nullptr; +} + +bool +js::LookupProperty(JSContext* cx, HandleObject obj, js::HandleId id, + MutableHandleObject objp, MutableHandleShape propp) +{ + /* NB: The logic of lookupProperty is implicitly reflected in + * BaselineIC.cpp's |EffectlesslyLookupProperty| logic. + * If this changes, please remember to update the logic there as well. + */ + if (LookupPropertyOp op = obj->getOpsLookupProperty()) + return op(cx, obj, id, objp, propp); + return LookupPropertyInline<CanGC>(cx, obj.as<NativeObject>(), id, objp, propp); +} + +bool +js::LookupName(JSContext* cx, HandlePropertyName name, HandleObject envChain, + MutableHandleObject objp, MutableHandleObject pobjp, MutableHandleShape propp) +{ + RootedId id(cx, NameToId(name)); + + for (RootedObject env(cx, envChain); env; env = env->enclosingEnvironment()) { + if (!LookupProperty(cx, env, id, pobjp, propp)) + return false; + if (propp) { + objp.set(env); + return true; + } + } + + objp.set(nullptr); + pobjp.set(nullptr); + propp.set(nullptr); + return true; +} + +bool +js::LookupNameNoGC(JSContext* cx, PropertyName* name, JSObject* envChain, + JSObject** objp, JSObject** pobjp, Shape** propp) +{ + AutoAssertNoException nogc(cx); + + MOZ_ASSERT(!*objp && !*pobjp && !*propp); + + for (JSObject* env = envChain; env; env = env->enclosingEnvironment()) { + if (env->getOpsLookupProperty()) + return false; + if (!LookupPropertyInline<NoGC>(cx, &env->as<NativeObject>(), NameToId(name), pobjp, propp)) + return false; + if (*propp) { + *objp = env; + return true; + } + } + + return true; +} + +bool +js::LookupNameWithGlobalDefault(JSContext* cx, HandlePropertyName name, HandleObject envChain, + MutableHandleObject objp) +{ + RootedId id(cx, NameToId(name)); + + RootedObject pobj(cx); + RootedShape shape(cx); + + RootedObject env(cx, envChain); + for (; !env->is<GlobalObject>(); env = env->enclosingEnvironment()) { + if (!LookupProperty(cx, env, id, &pobj, &shape)) + return false; + if (shape) + break; + } + + objp.set(env); + return true; +} + +bool +js::LookupNameUnqualified(JSContext* cx, HandlePropertyName name, HandleObject envChain, + MutableHandleObject objp) +{ + RootedId id(cx, NameToId(name)); + + RootedObject pobj(cx); + RootedShape shape(cx); + + RootedObject env(cx, envChain); + for (; !env->isUnqualifiedVarObj(); env = env->enclosingEnvironment()) { + if (!LookupProperty(cx, env, id, &pobj, &shape)) + return false; + if (shape) + break; + } + + // See note above RuntimeLexicalErrorObject. + if (pobj == env) { + bool isTDZ = false; + if (shape && name != cx->names().dotThis) { + // Treat Debugger environments specially for TDZ checks, as they + // look like non-native environments but in fact wrap native + // environments. + if (env->is<DebugEnvironmentProxy>()) { + RootedValue v(cx); + if (!env->as<DebugEnvironmentProxy>().getMaybeSentinelValue(cx, id, &v)) + return false; + isTDZ = IsUninitializedLexical(v); + } else { + isTDZ = IsUninitializedLexicalSlot(env, shape); + } + } + + if (isTDZ) { + env = RuntimeLexicalErrorObject::create(cx, env, JSMSG_UNINITIALIZED_LEXICAL); + if (!env) + return false; + } else if (env->is<LexicalEnvironmentObject>() && !shape->writable()) { + // Assigning to a named lambda callee name is a no-op in sloppy mode. + Rooted<LexicalEnvironmentObject*> lexicalEnv(cx, &env->as<LexicalEnvironmentObject>()); + if (lexicalEnv->isExtensible() || + lexicalEnv->scope().kind() != ScopeKind::NamedLambda) + { + MOZ_ASSERT(name != cx->names().dotThis); + env = RuntimeLexicalErrorObject::create(cx, env, JSMSG_BAD_CONST_ASSIGN); + if (!env) + return false; + } + } + } + + objp.set(env); + return true; +} + +bool +js::HasOwnProperty(JSContext* cx, HandleObject obj, HandleId id, bool* result) +{ + if (obj->is<ProxyObject>()) + return Proxy::hasOwn(cx, obj, id, result); + + if (GetOwnPropertyOp op = obj->getOpsGetOwnPropertyDescriptor()) { + Rooted<PropertyDescriptor> desc(cx); + if (!op(cx, obj, id, &desc)) + return false; + *result = !!desc.object(); + return true; + } + + RootedShape shape(cx); + if (!NativeLookupOwnProperty<CanGC>(cx, obj.as<NativeObject>(), id, &shape)) + return false; + *result = (shape != nullptr); + return true; +} + +bool +js::LookupPropertyPure(ExclusiveContext* cx, JSObject* obj, jsid id, JSObject** objp, + Shape** propp) +{ + bool isTypedArrayOutOfRange = false; + do { + if (!LookupOwnPropertyPure(cx, obj, id, propp, &isTypedArrayOutOfRange)) + return false; + + if (*propp) { + *objp = obj; + return true; + } + + if (isTypedArrayOutOfRange) { + *objp = nullptr; + return true; + } + + obj = obj->staticPrototype(); + } while (obj); + + *objp = nullptr; + *propp = nullptr; + return true; +} + +bool +js::LookupOwnPropertyPure(ExclusiveContext* cx, JSObject* obj, jsid id, Shape** propp, + bool* isTypedArrayOutOfRange /* = nullptr */) +{ + JS::AutoCheckCannotGC nogc; + if (isTypedArrayOutOfRange) + *isTypedArrayOutOfRange = false; + + if (obj->isNative()) { + // Search for a native dense element, typed array element, or property. + + if (JSID_IS_INT(id) && obj->as<NativeObject>().containsDenseElement(JSID_TO_INT(id))) { + MarkDenseOrTypedArrayElementFound<NoGC>(propp); + return true; + } + + if (obj->is<TypedArrayObject>()) { + uint64_t index; + if (IsTypedArrayIndex(id, &index)) { + if (index < obj->as<TypedArrayObject>().length()) { + MarkDenseOrTypedArrayElementFound<NoGC>(propp); + } else { + *propp = nullptr; + if (isTypedArrayOutOfRange) + *isTypedArrayOutOfRange = true; + } + return true; + } + } + + if (Shape* shape = obj->as<NativeObject>().lookupPure(id)) { + *propp = shape; + return true; + } + + // Fail if there's a resolve hook, unless the mayResolve hook tells + // us the resolve hook won't define a property with this id. + if (ClassMayResolveId(cx->names(), obj->getClass(), id, obj)) + return false; + } else if (obj->is<UnboxedPlainObject>()) { + if (obj->as<UnboxedPlainObject>().containsUnboxedOrExpandoProperty(cx, id)) { + MarkNonNativePropertyFound<NoGC>(propp); + return true; + } + } else if (obj->is<UnboxedArrayObject>()) { + if (obj->as<UnboxedArrayObject>().containsProperty(cx, id)) { + MarkNonNativePropertyFound<NoGC>(propp); + return true; + } + } else if (obj->is<TypedObject>()) { + if (obj->as<TypedObject>().typeDescr().hasProperty(cx->names(), id)) { + MarkNonNativePropertyFound<NoGC>(propp); + return true; + } + } else { + return false; + } + + *propp = nullptr; + return true; +} + +static inline bool +NativeGetPureInline(NativeObject* pobj, Shape* shape, Value* vp) +{ + /* Fail if we have a custom getter. */ + if (!shape->hasDefaultGetter()) + return false; + + if (shape->hasSlot()) { + *vp = pobj->getSlot(shape->slot()); + MOZ_ASSERT(!vp->isMagic()); + } else { + vp->setUndefined(); + } + + return true; +} + +bool +js::GetPropertyPure(ExclusiveContext* cx, JSObject* obj, jsid id, Value* vp) +{ + JSObject* pobj; + Shape* shape; + if (!LookupPropertyPure(cx, obj, id, &pobj, &shape)) + return false; + + if (!shape) { + vp->setUndefined(); + return true; + } + + return pobj->isNative() && NativeGetPureInline(&pobj->as<NativeObject>(), shape, vp); +} + +static inline bool +NativeGetGetterPureInline(Shape* shape, JSFunction** fp) +{ + if (shape->hasGetterObject()) { + if (shape->getterObject()->is<JSFunction>()) { + *fp = &shape->getterObject()->as<JSFunction>(); + return true; + } + } + + *fp = nullptr; + return true; +} + +bool +js::GetGetterPure(ExclusiveContext* cx, JSObject* obj, jsid id, JSFunction** fp) +{ + /* Just like GetPropertyPure, but get getter function, without invoking + * it. */ + JSObject* pobj; + Shape* shape; + if (!LookupPropertyPure(cx, obj, id, &pobj, &shape)) + return false; + + if (!shape) { + *fp = nullptr; + return true; + } + + return pobj->isNative() && NativeGetGetterPureInline(shape, fp); +} + +bool +js::GetOwnGetterPure(ExclusiveContext* cx, JSObject* obj, jsid id, JSFunction** fp) +{ + JS::AutoCheckCannotGC nogc; + Shape* shape; + if (!LookupOwnPropertyPure(cx, obj, id, &shape)) + return false; + + if (!shape) { + *fp = nullptr; + return true; + } + + return NativeGetGetterPureInline(shape, fp); +} + +bool +js::GetOwnNativeGetterPure(JSContext* cx, JSObject* obj, jsid id, JSNative* native) +{ + JS::AutoCheckCannotGC nogc; + *native = nullptr; + Shape* shape; + if (!LookupOwnPropertyPure(cx, obj, id, &shape)) + return false; + + if (!shape || IsImplicitDenseOrTypedArrayElement(shape) || !shape->hasGetterObject()) + return true; + + JSObject* getterObj = shape->getterObject(); + if (!getterObj->is<JSFunction>()) + return true; + + JSFunction* getter = &getterObj->as<JSFunction>(); + if (!getter->isNative()) + return true; + + *native = getter->native(); + return true; +} + +bool +js::HasOwnDataPropertyPure(JSContext* cx, JSObject* obj, jsid id, bool* result) +{ + Shape* shape = nullptr; + if (!LookupOwnPropertyPure(cx, obj, id, &shape)) + return false; + + *result = shape && !IsImplicitDenseOrTypedArrayElement(shape) && shape->hasDefaultGetter() && + shape->hasSlot(); + return true; +} + +bool +JSObject::reportReadOnly(JSContext* cx, jsid id, unsigned report) +{ + RootedValue val(cx, IdToValue(id)); + return ReportValueErrorFlags(cx, report, JSMSG_READ_ONLY, + JSDVG_IGNORE_STACK, val, nullptr, + nullptr, nullptr); +} + +bool +JSObject::reportNotConfigurable(JSContext* cx, jsid id, unsigned report) +{ + RootedValue val(cx, IdToValue(id)); + return ReportValueErrorFlags(cx, report, JSMSG_CANT_DELETE, + JSDVG_IGNORE_STACK, val, nullptr, + nullptr, nullptr); +} + +bool +JSObject::reportNotExtensible(JSContext* cx, unsigned report) +{ + RootedValue val(cx, ObjectValue(*this)); + return ReportValueErrorFlags(cx, report, JSMSG_OBJECT_NOT_EXTENSIBLE, + JSDVG_IGNORE_STACK, val, nullptr, + nullptr, nullptr); +} + +bool +js::GetPrototypeIfOrdinary(JSContext* cx, HandleObject obj, bool* isOrdinary, + MutableHandleObject protop) +{ + if (obj->is<js::ProxyObject>()) + return js::Proxy::getPrototypeIfOrdinary(cx, obj, isOrdinary, protop); + + *isOrdinary = true; + protop.set(obj->staticPrototype()); + return true; +} + +/*** ES6 standard internal methods ***************************************************************/ + +bool +js::SetPrototype(JSContext* cx, HandleObject obj, HandleObject proto, JS::ObjectOpResult& result) +{ + // The proxy trap subsystem fully handles prototype-setting for proxies + // with dynamic [[Prototype]]s. + if (obj->hasDynamicPrototype()) { + MOZ_ASSERT(obj->is<ProxyObject>()); + return Proxy::setPrototype(cx, obj, proto, result); + } + + /* + * ES6 9.1.2 step 3-4 if |obj.[[Prototype]]| has SameValue as |proto| return true. + * Since the values in question are objects, we can just compare pointers. + */ + if (proto == obj->staticPrototype()) + return result.succeed(); + + /* Disallow mutation of immutable [[Prototype]]s. */ + if (obj->staticPrototypeIsImmutable()) + return result.fail(JSMSG_CANT_SET_PROTO); + + /* + * Disallow mutating the [[Prototype]] on ArrayBuffer objects, which + * due to their complicated delegate-object shenanigans can't easily + * have a mutable [[Prototype]]. + */ + if (obj->is<ArrayBufferObject>()) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_SET_PROTO_OF, + "incompatible ArrayBuffer"); + return false; + } + + /* + * Disallow mutating the [[Prototype]] on Typed Objects, per the spec. + */ + if (obj->is<TypedObject>()) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_SET_PROTO_OF, + "incompatible TypedObject"); + return false; + } + + /* ES6 9.1.2 step 5 forbids changing [[Prototype]] if not [[Extensible]]. */ + bool extensible; + if (!IsExtensible(cx, obj, &extensible)) + return false; + if (!extensible) + return result.fail(JSMSG_CANT_SET_PROTO); + + // If this is a global object, resolve the Object class so that its + // [[Prototype]] chain is always properly immutable, even in the presence + // of lazy standard classes. + if (obj->is<GlobalObject>()) { + Rooted<GlobalObject*> global(cx, &obj->as<GlobalObject>()); + if (!GlobalObject::ensureConstructor(cx, global, JSProto_Object)) + return false; + } + + /* + * ES6 9.1.2 step 6 forbids generating cyclical prototype chains. But we + * have to do this comparison on the observable WindowProxy, not on the + * possibly-Window object we're setting the proto on. + */ + RootedObject objMaybeWindowProxy(cx, ToWindowProxyIfWindow(obj)); + RootedObject obj2(cx, proto); + while (obj2) { + MOZ_ASSERT(!IsWindow(obj2)); + if (obj2 == objMaybeWindowProxy) + return result.fail(JSMSG_CANT_SET_PROTO_CYCLE); + + bool isOrdinary; + if (!GetPrototypeIfOrdinary(cx, obj2, &isOrdinary, &obj2)) + return false; + if (!isOrdinary) + break; + } + + // Convert unboxed objects to their native representations before changing + // their prototype/group, as they depend on the group for their layout. + if (!MaybeConvertUnboxedObjectToNative(cx, obj)) + return false; + + Rooted<TaggedProto> taggedProto(cx, TaggedProto(proto)); + if (!SetClassAndProto(cx, obj, obj->getClass(), taggedProto)) + return false; + + return result.succeed(); +} + +bool +js::SetPrototype(JSContext* cx, HandleObject obj, HandleObject proto) +{ + ObjectOpResult result; + return SetPrototype(cx, obj, proto, result) && result.checkStrict(cx, obj); +} + +bool +js::PreventExtensions(JSContext* cx, HandleObject obj, ObjectOpResult& result, IntegrityLevel level) +{ + if (obj->is<ProxyObject>()) + return js::Proxy::preventExtensions(cx, obj, result); + + if (!obj->nonProxyIsExtensible()) + return result.succeed(); + + if (!MaybeConvertUnboxedObjectToNative(cx, obj)) + return false; + + // Force lazy properties to be resolved. + AutoIdVector props(cx); + if (!js::GetPropertyKeys(cx, obj, JSITER_HIDDEN | JSITER_OWNONLY, &props)) + return false; + + // Actually prevent extension. If the object is being frozen, do it by + // setting the frozen flag on both the object and the object group. + // Otherwise, fallback to sparsifying the object, which makes sure no + // element can be added without a call to isExtensible, at the cost of + // performance. + if (obj->isNative()) { + if (level == IntegrityLevel::Frozen) { + MarkObjectGroupFlags(cx, obj, OBJECT_FLAG_FROZEN); + if (!ObjectElements::FreezeElements(cx, obj.as<NativeObject>())) + return false; + } else if (!NativeObject::sparsifyDenseElements(cx, obj.as<NativeObject>())) { + return false; + } + } + + if (!obj->setFlags(cx, BaseShape::NOT_EXTENSIBLE, JSObject::GENERATE_SHAPE)) { + // We failed to mark the object non-extensible, so reset the frozen + // flag on the elements. + MOZ_ASSERT(obj->nonProxyIsExtensible()); + if (obj->isNative() && obj->as<NativeObject>().getElementsHeader()->isFrozen()) + obj->as<NativeObject>().getElementsHeader()->markNotFrozen(); + return false; + } + + return result.succeed(); +} + +bool +js::PreventExtensions(JSContext* cx, HandleObject obj, IntegrityLevel level) +{ + ObjectOpResult result; + return PreventExtensions(cx, obj, result, level) && result.checkStrict(cx, obj); +} + +bool +js::GetOwnPropertyDescriptor(JSContext* cx, HandleObject obj, HandleId id, + MutableHandle<PropertyDescriptor> desc) +{ + if (GetOwnPropertyOp op = obj->getOpsGetOwnPropertyDescriptor()) { + bool ok = op(cx, obj, id, desc); + if (ok) + desc.assertCompleteIfFound(); + return ok; + } + + return NativeGetOwnPropertyDescriptor(cx, obj.as<NativeObject>(), id, desc); +} + +bool +js::DefineProperty(JSContext* cx, HandleObject obj, HandleId id, Handle<PropertyDescriptor> desc) +{ + ObjectOpResult result; + return DefineProperty(cx, obj, id, desc, result) && + result.checkStrict(cx, obj, id); +} + +bool +js::DefineProperty(JSContext* cx, HandleObject obj, HandleId id, Handle<PropertyDescriptor> desc, + ObjectOpResult& result) +{ + desc.assertValid(); + if (DefinePropertyOp op = obj->getOpsDefineProperty()) + return op(cx, obj, id, desc, result); + return NativeDefineProperty(cx, obj.as<NativeObject>(), id, desc, result); +} + +bool +js::DefineProperty(ExclusiveContext* cx, HandleObject obj, HandleId id, HandleValue value, + JSGetterOp getter, JSSetterOp setter, unsigned attrs, + ObjectOpResult& result) +{ + MOZ_ASSERT(!(attrs & JSPROP_PROPOP_ACCESSORS)); + + Rooted<PropertyDescriptor> desc(cx); + desc.initFields(nullptr, value, attrs, getter, setter); + if (DefinePropertyOp op = obj->getOpsDefineProperty()) { + if (!cx->shouldBeJSContext()) + return false; + return op(cx->asJSContext(), obj, id, desc, result); + } + return NativeDefineProperty(cx, obj.as<NativeObject>(), id, desc, result); +} + +bool +js::DefineProperty(ExclusiveContext* cx, HandleObject obj, PropertyName* name, HandleValue value, + JSGetterOp getter, JSSetterOp setter, unsigned attrs, + ObjectOpResult& result) +{ + RootedId id(cx, NameToId(name)); + return DefineProperty(cx, obj, id, value, getter, setter, attrs, result); +} + +bool +js::DefineElement(ExclusiveContext* cx, HandleObject obj, uint32_t index, HandleValue value, + JSGetterOp getter, JSSetterOp setter, unsigned attrs, + ObjectOpResult& result) +{ + MOZ_ASSERT(getter != JS_PropertyStub); + MOZ_ASSERT(setter != JS_StrictPropertyStub); + + RootedId id(cx); + if (!IndexToId(cx, index, &id)) + return false; + return DefineProperty(cx, obj, id, value, getter, setter, attrs, result); +} + +bool +js::DefineProperty(ExclusiveContext* cx, HandleObject obj, HandleId id, HandleValue value, + JSGetterOp getter, JSSetterOp setter, unsigned attrs) +{ + ObjectOpResult result; + if (!DefineProperty(cx, obj, id, value, getter, setter, attrs, result)) + return false; + if (!result) { + if (!cx->shouldBeJSContext()) + return false; + result.reportError(cx->asJSContext(), obj, id); + return false; + } + return true; +} + +bool +js::DefineProperty(ExclusiveContext* cx, HandleObject obj, PropertyName* name, HandleValue value, + JSGetterOp getter, JSSetterOp setter, unsigned attrs) +{ + RootedId id(cx, NameToId(name)); + return DefineProperty(cx, obj, id, value, getter, setter, attrs); +} + +bool +js::DefineElement(ExclusiveContext* cx, HandleObject obj, uint32_t index, HandleValue value, + JSGetterOp getter, JSSetterOp setter, unsigned attrs) +{ + MOZ_ASSERT(getter != JS_PropertyStub); + MOZ_ASSERT(setter != JS_StrictPropertyStub); + + RootedId id(cx); + if (!IndexToId(cx, index, &id)) + return false; + return DefineProperty(cx, obj, id, value, getter, setter, attrs); +} + + +/*** SpiderMonkey nonstandard internal methods ***************************************************/ + +bool +js::SetImmutablePrototype(ExclusiveContext* cx, HandleObject obj, bool* succeeded) +{ + if (obj->hasDynamicPrototype()) { + if (!cx->shouldBeJSContext()) + return false; + return Proxy::setImmutablePrototype(cx->asJSContext(), obj, succeeded); + } + + if (!obj->setFlags(cx, BaseShape::IMMUTABLE_PROTOTYPE)) + return false; + *succeeded = true; + return true; +} + +bool +js::GetPropertyDescriptor(JSContext* cx, HandleObject obj, HandleId id, + MutableHandle<PropertyDescriptor> desc) +{ + RootedObject pobj(cx); + + for (pobj = obj; pobj;) { + if (pobj->is<ProxyObject>()) { + bool ok = Proxy::getPropertyDescriptor(cx, pobj, id, desc); + if (ok) + desc.assertCompleteIfFound(); + return ok; + } + + if (!GetOwnPropertyDescriptor(cx, pobj, id, desc)) + return false; + + if (desc.object()) + return true; + + if (!GetPrototype(cx, pobj, &pobj)) + return false; + } + + MOZ_ASSERT(!desc.object()); + return true; +} + +bool +js::WatchGuts(JSContext* cx, JS::HandleObject origObj, JS::HandleId id, JS::HandleObject callable) +{ + RootedObject obj(cx, ToWindowIfWindowProxy(origObj)); + if (obj->isNative()) { + // Use sparse indexes for watched objects, as dense elements can be + // written to without checking the watchpoint map. + if (!NativeObject::sparsifyDenseElements(cx, obj.as<NativeObject>())) + return false; + + MarkTypePropertyNonData(cx, obj, id); + } + + WatchpointMap* wpmap = cx->compartment()->watchpointMap; + if (!wpmap) { + wpmap = cx->runtime()->new_<WatchpointMap>(); + if (!wpmap || !wpmap->init()) { + ReportOutOfMemory(cx); + js_delete(wpmap); + return false; + } + cx->compartment()->watchpointMap = wpmap; + } + + return wpmap->watch(cx, obj, id, js::WatchHandler, callable); +} + +bool +js::UnwatchGuts(JSContext* cx, JS::HandleObject origObj, JS::HandleId id) +{ + // Looking in the map for an unsupported object will never hit, so we don't + // need to check for nativeness or watchable-ness here. + RootedObject obj(cx, ToWindowIfWindowProxy(origObj)); + if (WatchpointMap* wpmap = cx->compartment()->watchpointMap) + wpmap->unwatch(obj, id, nullptr, nullptr); + return true; +} + +bool +js::WatchProperty(JSContext* cx, HandleObject obj, HandleId id, HandleObject callable) +{ + if (WatchOp op = obj->getOpsWatch()) + return op(cx, obj, id, callable); + + if (!obj->isNative() || obj->is<TypedArrayObject>()) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_WATCH, + obj->getClass()->name); + return false; + } + + return WatchGuts(cx, obj, id, callable); +} + +bool +js::UnwatchProperty(JSContext* cx, HandleObject obj, HandleId id) +{ + if (UnwatchOp op = obj->getOpsUnwatch()) + return op(cx, obj, id); + + return UnwatchGuts(cx, obj, id); +} + +const char* +js::GetObjectClassName(JSContext* cx, HandleObject obj) +{ + assertSameCompartment(cx, obj); + + if (obj->is<ProxyObject>()) + return Proxy::className(cx, obj); + + return obj->getClass()->name; +} + + +/* * */ + +bool +js::HasDataProperty(JSContext* cx, NativeObject* obj, jsid id, Value* vp) +{ + if (JSID_IS_INT(id) && obj->containsDenseElement(JSID_TO_INT(id))) { + *vp = obj->getDenseElement(JSID_TO_INT(id)); + return true; + } + + if (Shape* shape = obj->lookup(cx, id)) { + if (shape->hasDefaultGetter() && shape->hasSlot()) { + *vp = obj->getSlot(shape->slot()); + return true; + } + } + + return false; +} + +extern bool +PropertySpecNameToId(JSContext* cx, const char* name, MutableHandleId id, + js::PinningBehavior pin = js::DoNotPinAtom); + +static bool +DefineFunctionFromSpec(JSContext* cx, HandleObject obj, const JSFunctionSpec* fs, unsigned flags, + DefineAsIntrinsic intrinsic) +{ + GetterOp gop; + SetterOp sop; + if (flags & JSFUN_STUB_GSOPS) { + // JSFUN_STUB_GSOPS is a request flag only, not stored in fun->flags or + // the defined property's attributes. + flags &= ~JSFUN_STUB_GSOPS; + gop = nullptr; + sop = nullptr; + } else { + gop = obj->getClass()->getGetProperty(); + sop = obj->getClass()->getSetProperty(); + MOZ_ASSERT(gop != JS_PropertyStub); + MOZ_ASSERT(sop != JS_StrictPropertyStub); + } + + RootedId id(cx); + if (!PropertySpecNameToId(cx, fs->name, &id)) + return false; + + JSFunction* fun = NewFunctionFromSpec(cx, fs, id); + if (!fun) + return false; + + if (intrinsic == AsIntrinsic) + fun->setIsIntrinsic(); + + RootedValue funVal(cx, ObjectValue(*fun)); + return DefineProperty(cx, obj, id, funVal, gop, sop, flags & ~JSFUN_FLAGS_MASK); +} + +bool +js::DefineFunctions(JSContext* cx, HandleObject obj, const JSFunctionSpec* fs, + DefineAsIntrinsic intrinsic) +{ + for (; fs->name; fs++) { + if (!DefineFunctionFromSpec(cx, obj, fs, fs->flags, intrinsic)) + return false; + } + return true; +} + + +/*** ToPrimitive *************************************************************/ + +/* + * Gets |obj[id]|. If that value's not callable, returns true and stores an + * object value in *vp. If it's callable, calls it with no arguments and |obj| + * as |this|, returning the result in *vp. + * + * This is a mini-abstraction for ES6 draft rev 36 (2015 Mar 17), + * 7.1.1, second algorithm (OrdinaryToPrimitive), steps 5.a-c. + */ +static bool +MaybeCallMethod(JSContext* cx, HandleObject obj, HandleId id, MutableHandleValue vp) +{ + if (!GetProperty(cx, obj, obj, id, vp)) + return false; + if (!IsCallable(vp)) { + vp.setObject(*obj); + return true; + } + + return js::Call(cx, vp, obj, vp); +} + +static bool +ReportCantConvert(JSContext* cx, unsigned errorNumber, HandleObject obj, JSType hint) +{ + const Class* clasp = obj->getClass(); + + // Avoid recursive death when decompiling in ReportValueError. + RootedString str(cx); + if (hint == JSTYPE_STRING) { + str = JS_AtomizeAndPinString(cx, clasp->name); + if (!str) + return false; + } else { + str = nullptr; + } + + RootedValue val(cx, ObjectValue(*obj)); + ReportValueError2(cx, errorNumber, JSDVG_SEARCH_STACK, val, str, + hint == JSTYPE_VOID + ? "primitive type" + : hint == JSTYPE_STRING ? "string" : "number"); + return false; +} + +bool +JS::OrdinaryToPrimitive(JSContext* cx, HandleObject obj, JSType hint, MutableHandleValue vp) +{ + MOZ_ASSERT(hint == JSTYPE_NUMBER || hint == JSTYPE_STRING || hint == JSTYPE_VOID); + + Rooted<jsid> id(cx); + + const Class* clasp = obj->getClass(); + if (hint == JSTYPE_STRING) { + id = NameToId(cx->names().toString); + + /* Optimize (new String(...)).toString(). */ + if (clasp == &StringObject::class_) { + StringObject* nobj = &obj->as<StringObject>(); + if (ClassMethodIsNative(cx, nobj, &StringObject::class_, id, str_toString)) { + vp.setString(nobj->unbox()); + return true; + } + } + + if (!MaybeCallMethod(cx, obj, id, vp)) + return false; + if (vp.isPrimitive()) + return true; + + id = NameToId(cx->names().valueOf); + if (!MaybeCallMethod(cx, obj, id, vp)) + return false; + if (vp.isPrimitive()) + return true; + } else { + id = NameToId(cx->names().valueOf); + + /* Optimize new String(...).valueOf(). */ + if (clasp == &StringObject::class_) { + StringObject* nobj = &obj->as<StringObject>(); + if (ClassMethodIsNative(cx, nobj, &StringObject::class_, id, str_toString)) { + vp.setString(nobj->unbox()); + return true; + } + } + + /* Optimize new Number(...).valueOf(). */ + if (clasp == &NumberObject::class_) { + NumberObject* nobj = &obj->as<NumberObject>(); + if (ClassMethodIsNative(cx, nobj, &NumberObject::class_, id, num_valueOf)) { + vp.setNumber(nobj->unbox()); + return true; + } + } + + if (!MaybeCallMethod(cx, obj, id, vp)) + return false; + if (vp.isPrimitive()) + return true; + + id = NameToId(cx->names().toString); + if (!MaybeCallMethod(cx, obj, id, vp)) + return false; + if (vp.isPrimitive()) + return true; + } + + return ReportCantConvert(cx, JSMSG_CANT_CONVERT_TO, obj, hint); +} + +bool +js::ToPrimitiveSlow(JSContext* cx, JSType preferredType, MutableHandleValue vp) +{ + // Step numbers refer to the first algorithm listed in ES6 draft rev 36 + // (2015 Mar 17) 7.1.1 ToPrimitive. + MOZ_ASSERT(preferredType == JSTYPE_VOID || + preferredType == JSTYPE_STRING || + preferredType == JSTYPE_NUMBER); + RootedObject obj(cx, &vp.toObject()); + + // Steps 4-5. + RootedId id(cx, SYMBOL_TO_JSID(cx->wellKnownSymbols().toPrimitive)); + RootedValue method(cx); + if (!GetProperty(cx, obj, obj, id, &method)) + return false; + + // Step 6. + if (!method.isUndefined()) { + // Step 6 of GetMethod. js::Call() below would do this check and throw a + // TypeError anyway, but this produces a better error message. + if (!IsCallable(method)) + return ReportCantConvert(cx, JSMSG_TOPRIMITIVE_NOT_CALLABLE, obj, preferredType); + + // Steps 1-3, 6.a-b. + RootedValue arg0(cx, StringValue(preferredType == JSTYPE_STRING + ? cx->names().string + : preferredType == JSTYPE_NUMBER + ? cx->names().number + : cx->names().default_)); + + if (!js::Call(cx, method, vp, arg0, vp)) + return false; + + // Steps 6.c-d. + if (vp.isObject()) + return ReportCantConvert(cx, JSMSG_TOPRIMITIVE_RETURNED_OBJECT, obj, preferredType); + return true; + } + + return OrdinaryToPrimitive(cx, obj, preferredType, vp); +} + + +/* * */ + +bool +js::IsDelegate(JSContext* cx, HandleObject obj, const js::Value& v, bool* result) +{ + if (v.isPrimitive()) { + *result = false; + return true; + } + return IsDelegateOfObject(cx, obj, &v.toObject(), result); +} + +bool +js::IsDelegateOfObject(JSContext* cx, HandleObject protoObj, JSObject* obj, bool* result) +{ + RootedObject obj2(cx, obj); + for (;;) { + if (!GetPrototype(cx, obj2, &obj2)) + return false; + if (!obj2) { + *result = false; + return true; + } + if (obj2 == protoObj) { + *result = true; + return true; + } + } +} + +JSObject* +js::GetBuiltinPrototypePure(GlobalObject* global, JSProtoKey protoKey) +{ + MOZ_ASSERT(JSProto_Null <= protoKey); + MOZ_ASSERT(protoKey < JSProto_LIMIT); + + if (protoKey != JSProto_Null) { + const Value& v = global->getPrototype(protoKey); + if (v.isObject()) + return &v.toObject(); + } + + return nullptr; +} + +JSObject* +js::PrimitiveToObject(JSContext* cx, const Value& v) +{ + if (v.isString()) { + Rooted<JSString*> str(cx, v.toString()); + return StringObject::create(cx, str); + } + if (v.isNumber()) + return NumberObject::create(cx, v.toNumber()); + if (v.isBoolean()) + return BooleanObject::create(cx, v.toBoolean()); + MOZ_ASSERT(v.isSymbol()); + RootedSymbol symbol(cx, v.toSymbol()); + return SymbolObject::create(cx, symbol); +} + +/* + * Invokes the ES5 ToObject algorithm on vp, returning the result. If vp might + * already be an object, use ToObject. reportCantConvert controls how null and + * undefined errors are reported. + * + * Callers must handle the already-object case. + */ +JSObject* +js::ToObjectSlow(JSContext* cx, JS::HandleValue val, bool reportScanStack) +{ + MOZ_ASSERT(!val.isMagic()); + MOZ_ASSERT(!val.isObject()); + + if (val.isNullOrUndefined()) { + if (reportScanStack) { + ReportIsNullOrUndefined(cx, JSDVG_SEARCH_STACK, val, nullptr); + } else { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_CONVERT_TO, + val.isNull() ? "null" : "undefined", "object"); + } + return nullptr; + } + + return PrimitiveToObject(cx, val); +} + +Value +js::GetThisValue(JSObject* obj) +{ + if (obj->is<GlobalObject>()) + return ObjectValue(*ToWindowProxyIfWindow(obj)); + + if (obj->is<LexicalEnvironmentObject>()) { + if (!obj->as<LexicalEnvironmentObject>().isExtensible()) + return UndefinedValue(); + return obj->as<LexicalEnvironmentObject>().thisValue(); + } + + if (obj->is<ModuleEnvironmentObject>()) + return UndefinedValue(); + + if (obj->is<WithEnvironmentObject>()) + return ObjectValue(*obj->as<WithEnvironmentObject>().withThis()); + + if (obj->is<NonSyntacticVariablesObject>()) + return GetThisValue(obj->enclosingEnvironment()); + + return ObjectValue(*obj); +} + +class GetObjectSlotNameFunctor : public JS::CallbackTracer::ContextFunctor +{ + JSObject* obj; + + public: + explicit GetObjectSlotNameFunctor(JSObject* ctx) : obj(ctx) {} + virtual void operator()(JS::CallbackTracer* trc, char* buf, size_t bufsize) override; +}; + +void +GetObjectSlotNameFunctor::operator()(JS::CallbackTracer* trc, char* buf, size_t bufsize) +{ + MOZ_ASSERT(trc->contextIndex() != JS::CallbackTracer::InvalidIndex); + + uint32_t slot = uint32_t(trc->contextIndex()); + + Shape* shape; + if (obj->isNative()) { + shape = obj->as<NativeObject>().lastProperty(); + while (shape && (!shape->hasSlot() || shape->slot() != slot)) + shape = shape->previous(); + } else { + shape = nullptr; + } + + if (!shape) { + do { + const char* slotname = nullptr; + const char* pattern = nullptr; + if (obj->is<GlobalObject>()) { + pattern = "CLASS_OBJECT(%s)"; + if (false) + ; +#define TEST_SLOT_MATCHES_PROTOTYPE(name,code,init,clasp) \ + else if ((code) == slot) { slotname = js_##name##_str; } + JS_FOR_EACH_PROTOTYPE(TEST_SLOT_MATCHES_PROTOTYPE) +#undef TEST_SLOT_MATCHES_PROTOTYPE + } else { + pattern = "%s"; + if (obj->is<EnvironmentObject>()) { + if (slot == EnvironmentObject::enclosingEnvironmentSlot()) { + slotname = "enclosing_environment"; + } else if (obj->is<CallObject>()) { + if (slot == CallObject::calleeSlot()) + slotname = "callee_slot"; + } else if (obj->is<WithEnvironmentObject>()) { + if (slot == WithEnvironmentObject::objectSlot()) + slotname = "with_object"; + else if (slot == WithEnvironmentObject::thisSlot()) + slotname = "with_this"; + } + } + } + + if (slotname) + snprintf(buf, bufsize, pattern, slotname); + else + snprintf(buf, bufsize, "**UNKNOWN SLOT %" PRIu32 "**", slot); + } while (false); + } else { + jsid propid = shape->propid(); + if (JSID_IS_INT(propid)) { + snprintf(buf, bufsize, "%" PRId32, JSID_TO_INT(propid)); + } else if (JSID_IS_ATOM(propid)) { + PutEscapedString(buf, bufsize, JSID_TO_ATOM(propid), 0); + } else if (JSID_IS_SYMBOL(propid)) { + snprintf(buf, bufsize, "**SYMBOL KEY**"); + } else { + snprintf(buf, bufsize, "**FINALIZED ATOM KEY**"); + } + } +} + +bool +js::ReportGetterOnlyAssignment(JSContext* cx, bool strict) +{ + return JS_ReportErrorFlagsAndNumberASCII(cx, + strict + ? JSREPORT_ERROR + : JSREPORT_WARNING | JSREPORT_STRICT, + GetErrorMessage, nullptr, + JSMSG_GETTER_ONLY); +} + + +/*** Debugging routines **************************************************************************/ + +#ifdef DEBUG + +/* + * Routines to print out values during debugging. These are FRIEND_API to help + * the debugger find them and to support temporarily hacking js::Dump* calls + * into other code. + */ + +static void +dumpValue(const Value& v, FILE* fp) +{ + if (v.isNull()) + fprintf(fp, "null"); + else if (v.isUndefined()) + fprintf(fp, "undefined"); + else if (v.isInt32()) + fprintf(fp, "%d", v.toInt32()); + else if (v.isDouble()) + fprintf(fp, "%g", v.toDouble()); + else if (v.isString()) + v.toString()->dump(fp); + else if (v.isSymbol()) + v.toSymbol()->dump(fp); + else if (v.isObject() && v.toObject().is<JSFunction>()) { + JSFunction* fun = &v.toObject().as<JSFunction>(); + if (fun->displayAtom()) { + fputs("<function ", fp); + FileEscapedString(fp, fun->displayAtom(), 0); + } else { + fputs("<unnamed function", fp); + } + if (fun->hasScript()) { + JSScript* script = fun->nonLazyScript(); + fprintf(fp, " (%s:%" PRIuSIZE ")", + script->filename() ? script->filename() : "", script->lineno()); + } + fprintf(fp, " at %p>", (void*) fun); + } else if (v.isObject()) { + JSObject* obj = &v.toObject(); + const Class* clasp = obj->getClass(); + fprintf(fp, "<%s%s at %p>", + clasp->name, + (clasp == &PlainObject::class_) ? "" : " object", + (void*) obj); + } else if (v.isBoolean()) { + if (v.toBoolean()) + fprintf(fp, "true"); + else + fprintf(fp, "false"); + } else if (v.isMagic()) { + fprintf(fp, "<invalid"); +#ifdef DEBUG + switch (v.whyMagic()) { + case JS_ELEMENTS_HOLE: fprintf(fp, " elements hole"); break; + case JS_NO_ITER_VALUE: fprintf(fp, " no iter value"); break; + case JS_GENERATOR_CLOSING: fprintf(fp, " generator closing"); break; + case JS_OPTIMIZED_OUT: fprintf(fp, " optimized out"); break; + default: fprintf(fp, " ?!"); break; + } +#endif + fprintf(fp, ">"); + } else { + fprintf(fp, "unexpected value"); + } +} + +JS_FRIEND_API(void) +js::DumpValue(const Value& val, FILE* fp) +{ + dumpValue(val, fp); + fputc('\n', fp); +} + +JS_FRIEND_API(void) +js::DumpId(jsid id, FILE* fp) +{ + fprintf(fp, "jsid %p = ", (void*) JSID_BITS(id)); + dumpValue(IdToValue(id), fp); + fputc('\n', fp); +} + +static void +DumpProperty(const NativeObject* obj, Shape& shape, FILE* fp) +{ + jsid id = shape.propid(); + uint8_t attrs = shape.attributes(); + + fprintf(fp, " ((js::Shape*) %p) ", (void*) &shape); + if (attrs & JSPROP_ENUMERATE) fprintf(fp, "enumerate "); + if (attrs & JSPROP_READONLY) fprintf(fp, "readonly "); + if (attrs & JSPROP_PERMANENT) fprintf(fp, "permanent "); + if (attrs & JSPROP_SHARED) fprintf(fp, "shared "); + + if (shape.hasGetterValue()) + fprintf(fp, "getterValue=%p ", (void*) shape.getterObject()); + else if (!shape.hasDefaultGetter()) + fprintf(fp, "getterOp=%p ", JS_FUNC_TO_DATA_PTR(void*, shape.getterOp())); + + if (shape.hasSetterValue()) + fprintf(fp, "setterValue=%p ", (void*) shape.setterObject()); + else if (!shape.hasDefaultSetter()) + fprintf(fp, "setterOp=%p ", JS_FUNC_TO_DATA_PTR(void*, shape.setterOp())); + + if (JSID_IS_ATOM(id) || JSID_IS_INT(id) || JSID_IS_SYMBOL(id)) + dumpValue(js::IdToValue(id), fp); + else + fprintf(fp, "unknown jsid %p", (void*) JSID_BITS(id)); + + uint32_t slot = shape.hasSlot() ? shape.maybeSlot() : SHAPE_INVALID_SLOT; + fprintf(fp, ": slot %d", slot); + if (shape.hasSlot()) { + fprintf(fp, " = "); + dumpValue(obj->getSlot(slot), fp); + } else if (slot != SHAPE_INVALID_SLOT) { + fprintf(fp, " (INVALID!)"); + } + fprintf(fp, "\n"); +} + +bool +JSObject::uninlinedIsProxy() const +{ + return is<ProxyObject>(); +} + +void +JSObject::dump(FILE* fp) const +{ + const JSObject* obj = this; + JSObject* globalObj = &global(); + fprintf(fp, "object %p from global %p [%s]\n", (void*) obj, + (void*) globalObj, globalObj->getClass()->name); + const Class* clasp = obj->getClass(); + fprintf(fp, "class %p %s\n", (const void*)clasp, clasp->name); + + if (obj->hasLazyGroup()) { + fprintf(fp, "lazy group\n"); + } else { + const ObjectGroup* group = obj->group(); + fprintf(fp, "group %p\n", (const void*)group); + } + + fprintf(fp, "flags:"); + if (obj->isDelegate()) fprintf(fp, " delegate"); + if (!obj->is<ProxyObject>() && !obj->nonProxyIsExtensible()) fprintf(fp, " not_extensible"); + if (obj->isIndexed()) fprintf(fp, " indexed"); + if (obj->isBoundFunction()) fprintf(fp, " bound_function"); + if (obj->isQualifiedVarObj()) fprintf(fp, " varobj"); + if (obj->isUnqualifiedVarObj()) fprintf(fp, " unqualified_varobj"); + if (obj->watched()) fprintf(fp, " watched"); + if (obj->isIteratedSingleton()) fprintf(fp, " iterated_singleton"); + if (obj->isNewGroupUnknown()) fprintf(fp, " new_type_unknown"); + if (obj->hasUncacheableProto()) fprintf(fp, " has_uncacheable_proto"); + if (obj->hadElementsAccess()) fprintf(fp, " had_elements_access"); + if (obj->wasNewScriptCleared()) fprintf(fp, " new_script_cleared"); + if (obj->hasStaticPrototype() && obj->staticPrototypeIsImmutable()) + fprintf(fp, " immutable_prototype"); + + if (obj->isNative()) { + const NativeObject* nobj = &obj->as<NativeObject>(); + if (nobj->inDictionaryMode()) + fprintf(fp, " inDictionaryMode"); + if (nobj->hasShapeTable()) + fprintf(fp, " hasShapeTable"); + } + fprintf(fp, "\n"); + + if (obj->isNative()) { + const NativeObject* nobj = &obj->as<NativeObject>(); + uint32_t slots = nobj->getDenseInitializedLength(); + if (slots) { + fprintf(fp, "elements\n"); + for (uint32_t i = 0; i < slots; i++) { + fprintf(fp, " %3d: ", i); + dumpValue(nobj->getDenseElement(i), fp); + fprintf(fp, "\n"); + fflush(fp); + } + } + } + + fprintf(fp, "proto "); + TaggedProto proto = obj->taggedProto(); + if (proto.isDynamic()) + fprintf(fp, "<dynamic>"); + else + dumpValue(ObjectOrNullValue(proto.toObjectOrNull()), fp); + fputc('\n', fp); + + if (clasp->flags & JSCLASS_HAS_PRIVATE) + fprintf(fp, "private %p\n", obj->as<NativeObject>().getPrivate()); + + if (!obj->isNative()) + fprintf(fp, "not native\n"); + + uint32_t reservedEnd = JSCLASS_RESERVED_SLOTS(clasp); + uint32_t slots = obj->isNative() ? obj->as<NativeObject>().slotSpan() : 0; + uint32_t stop = obj->isNative() ? reservedEnd : slots; + if (stop > 0) + fprintf(fp, obj->isNative() ? "reserved slots:\n" : "slots:\n"); + for (uint32_t i = 0; i < stop; i++) { + fprintf(fp, " %3d ", i); + if (i < reservedEnd) + fprintf(fp, "(reserved) "); + fprintf(fp, "= "); + dumpValue(obj->as<NativeObject>().getSlot(i), fp); + fputc('\n', fp); + } + + if (obj->isNative()) { + fprintf(fp, "properties:\n"); + Vector<Shape*, 8, SystemAllocPolicy> props; + for (Shape::Range<NoGC> r(obj->as<NativeObject>().lastProperty()); !r.empty(); r.popFront()) { + if (!props.append(&r.front())) { + fprintf(fp, "(OOM while appending properties)\n"); + break; + } + } + for (size_t i = props.length(); i-- != 0;) + DumpProperty(&obj->as<NativeObject>(), *props[i], fp); + } + fputc('\n', fp); +} + +// For debuggers. +void +JSObject::dump() const +{ + dump(stderr); +} + +static void +MaybeDumpScope(Scope* scope, FILE* fp) +{ + if (scope) { + fprintf(fp, " scope: %s\n", ScopeKindString(scope->kind())); + for (BindingIter bi(scope); bi; bi++) { + fprintf(fp, " "); + dumpValue(StringValue(bi.name()), fp); + fputc('\n', fp); + } + } +} + +static void +MaybeDumpValue(const char* name, const Value& v, FILE* fp) +{ + if (!v.isNull()) { + fprintf(fp, " %s: ", name); + dumpValue(v, fp); + fputc('\n', fp); + } +} + +JS_FRIEND_API(void) +js::DumpInterpreterFrame(JSContext* cx, FILE* fp, InterpreterFrame* start) +{ + /* This should only called during live debugging. */ + ScriptFrameIter i(cx); + if (!start) { + if (i.done()) { + fprintf(fp, "no stack for cx = %p\n", (void*) cx); + return; + } + } else { + while (!i.done() && !i.isJit() && i.interpFrame() != start) + ++i; + + if (i.done()) { + fprintf(fp, "fp = %p not found in cx = %p\n", + (void*)start, (void*)cx); + return; + } + } + + for (; !i.done(); ++i) { + if (i.isJit()) + fprintf(fp, "JIT frame\n"); + else + fprintf(fp, "InterpreterFrame at %p\n", (void*) i.interpFrame()); + + if (i.isFunctionFrame()) { + fprintf(fp, "callee fun: "); + RootedValue v(cx); + JSObject* fun = i.callee(cx); + v.setObject(*fun); + dumpValue(v, fp); + } else { + fprintf(fp, "global or eval frame, no callee"); + } + fputc('\n', fp); + + fprintf(fp, "file %s line %" PRIuSIZE "\n", + i.script()->filename(), i.script()->lineno()); + + if (jsbytecode* pc = i.pc()) { + fprintf(fp, " pc = %p\n", pc); + fprintf(fp, " current op: %s\n", CodeName[*pc]); + MaybeDumpScope(i.script()->lookupScope(pc), fp); + } + if (i.isFunctionFrame()) + MaybeDumpValue("this", i.thisArgument(cx), fp); + if (!i.isJit()) { + fprintf(fp, " rval: "); + dumpValue(i.interpFrame()->returnValue(), fp); + fputc('\n', fp); + } + + fprintf(fp, " flags:"); + if (i.isConstructing()) + fprintf(fp, " constructing"); + if (!i.isJit() && i.interpFrame()->isDebuggerEvalFrame()) + fprintf(fp, " debugger eval"); + if (i.isEvalFrame()) + fprintf(fp, " eval"); + fputc('\n', fp); + + fprintf(fp, " envChain: (JSObject*) %p\n", (void*) i.environmentChain(cx)); + + fputc('\n', fp); + } +} + +#endif /* DEBUG */ + +JS_FRIEND_API(void) +js::DumpBacktrace(JSContext* cx, FILE* fp) +{ + Sprinter sprinter(cx, false); + if (!sprinter.init()) { + fprintf(fp, "js::DumpBacktrace: OOM\n"); + return; + } + size_t depth = 0; + for (AllFramesIter i(cx); !i.done(); ++i, ++depth) { + const char* filename; + unsigned line; + if (i.hasScript()) { + filename = JS_GetScriptFilename(i.script()); + line = PCToLineNumber(i.script(), i.pc()); + } else { + filename = i.filename(); + line = i.computeLine(); + } + char frameType = + i.isInterp() ? 'i' : + i.isBaseline() ? 'b' : + i.isIon() ? 'I' : + i.isWasm() ? 'W' : + '?'; + + sprinter.printf("#%" PRIuSIZE " %14p %c %s:%d", + depth, i.rawFramePtr(), frameType, filename, line); + + if (i.hasScript()) { + sprinter.printf(" (%p @ %" PRIuSIZE ")\n", + i.script(), i.script()->pcToOffset(i.pc())); + } else { + sprinter.printf(" (%p)\n", i.pc()); + } + } + fprintf(fp, "%s", sprinter.string()); +#ifdef XP_WIN32 + if (IsDebuggerPresent()) + OutputDebugStringA(sprinter.string()); +#endif +} + +JS_FRIEND_API(void) +js::DumpBacktrace(JSContext* cx) +{ + DumpBacktrace(cx, stdout); +} + +/* * */ + +js::gc::AllocKind +JSObject::allocKindForTenure(const js::Nursery& nursery) const +{ + if (is<ArrayObject>()) { + const ArrayObject& aobj = as<ArrayObject>(); + MOZ_ASSERT(aobj.numFixedSlots() == 0); + + /* Use minimal size object if we are just going to copy the pointer. */ + if (!nursery.isInside(aobj.getElementsHeader())) + return AllocKind::OBJECT0_BACKGROUND; + + size_t nelements = aobj.getDenseCapacity(); + return GetBackgroundAllocKind(GetGCArrayKind(nelements)); + } + + if (is<JSFunction>()) + return as<JSFunction>().getAllocKind(); + + /* + * Typed arrays in the nursery may have a lazily allocated buffer, make + * sure there is room for the array's fixed data when moving the array. + */ + if (is<TypedArrayObject>() && !as<TypedArrayObject>().hasBuffer()) { + size_t nbytes = as<TypedArrayObject>().byteLength(); + if (as<TypedArrayObject>().hasInlineElements()) + return GetBackgroundAllocKind(TypedArrayObject::AllocKindForLazyBuffer(nbytes)); + return GetGCObjectKind(getClass()); + } + + // Proxies that are CrossCompartmentWrappers may be nursery allocated. + if (IsProxy(this)) + return as<ProxyObject>().allocKindForTenure(); + + // Unboxed plain objects are sized according to the data they store. + if (is<UnboxedPlainObject>()) { + size_t nbytes = as<UnboxedPlainObject>().layoutDontCheckGeneration().size(); + return GetGCObjectKindForBytes(UnboxedPlainObject::offsetOfData() + nbytes); + } + + // Unboxed arrays use inline data if their size is small enough. + if (is<UnboxedArrayObject>()) { + const UnboxedArrayObject* nobj = &as<UnboxedArrayObject>(); + size_t nbytes = UnboxedArrayObject::offsetOfInlineElements() + + nobj->capacity() * nobj->elementSize(); + if (nbytes <= JSObject::MAX_BYTE_SIZE) + return GetGCObjectKindForBytes(nbytes); + return AllocKind::OBJECT0; + } + + // Inlined typed objects are followed by their data, so make sure we copy + // it all over to the new object. + if (is<InlineTypedObject>()) { + // Figure out the size of this object, from the prototype's TypeDescr. + // The objects we are traversing here are all tenured, so we don't need + // to check forwarding pointers. + TypeDescr& descr = as<InlineTypedObject>().typeDescr(); + MOZ_ASSERT(!IsInsideNursery(&descr)); + return InlineTypedObject::allocKindForTypeDescriptor(&descr); + } + + // Outline typed objects use the minimum allocation kind. + if (is<OutlineTypedObject>()) + return AllocKind::OBJECT0; + + // All nursery allocatable non-native objects are handled above. + MOZ_ASSERT(isNative()); + + AllocKind kind = GetGCObjectFixedSlotsKind(as<NativeObject>().numFixedSlots()); + MOZ_ASSERT(!IsBackgroundFinalized(kind)); + if (!CanBeFinalizedInBackground(kind, getClass())) + return kind; + return GetBackgroundAllocKind(kind); +} + +void +JSObject::addSizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf, JS::ClassInfo* info) +{ + if (is<NativeObject>() && as<NativeObject>().hasDynamicSlots()) + info->objectsMallocHeapSlots += mallocSizeOf(as<NativeObject>().slots_); + + if (is<NativeObject>() && as<NativeObject>().hasDynamicElements()) { + js::ObjectElements* elements = as<NativeObject>().getElementsHeader(); + if (!elements->isCopyOnWrite() || elements->ownerObject() == this) + info->objectsMallocHeapElementsNormal += mallocSizeOf(elements); + } + + // Other things may be measured in the future if DMD indicates it is worthwhile. + if (is<JSFunction>() || + is<PlainObject>() || + is<ArrayObject>() || + is<CallObject>() || + is<RegExpObject>() || + is<ProxyObject>()) + { + // Do nothing. But this function is hot, and we win by getting the + // common cases out of the way early. Some stats on the most common + // classes, as measured during a vanilla browser session: + // - (53.7%, 53.7%): Function + // - (18.0%, 71.7%): Object + // - (16.9%, 88.6%): Array + // - ( 3.9%, 92.5%): Call + // - ( 2.8%, 95.3%): RegExp + // - ( 1.0%, 96.4%): Proxy + + // Note that any JSClass that is special cased below likely needs to + // specify the JSCLASS_DELAY_METADATA_CALLBACK flag, or else we will + // probably crash if the object metadata callback attempts to get the + // size of the new object (which Debugger code does) before private + // slots are initialized. + } else if (is<ArgumentsObject>()) { + info->objectsMallocHeapMisc += as<ArgumentsObject>().sizeOfMisc(mallocSizeOf); + } else if (is<RegExpStaticsObject>()) { + info->objectsMallocHeapMisc += as<RegExpStaticsObject>().sizeOfData(mallocSizeOf); + } else if (is<PropertyIteratorObject>()) { + info->objectsMallocHeapMisc += as<PropertyIteratorObject>().sizeOfMisc(mallocSizeOf); + } else if (is<ArrayBufferObject>()) { + ArrayBufferObject::addSizeOfExcludingThis(this, mallocSizeOf, info); + } else if (is<SharedArrayBufferObject>()) { + SharedArrayBufferObject::addSizeOfExcludingThis(this, mallocSizeOf, info); +#ifdef JS_HAS_CTYPES + } else { + // This must be the last case. + info->objectsMallocHeapMisc += + js::SizeOfDataIfCDataObject(mallocSizeOf, const_cast<JSObject*>(this)); +#endif + } +} + +size_t +JSObject::sizeOfIncludingThisInNursery() const +{ + // This function doesn't concern itself yet with typed objects (bug 1133593) + // nor unboxed objects (bug 1133592). + + MOZ_ASSERT(!isTenured()); + + const Nursery& nursery = compartment()->runtimeFromAnyThread()->gc.nursery; + size_t size = Arena::thingSize(allocKindForTenure(nursery)); + + if (is<NativeObject>()) { + const NativeObject& native = as<NativeObject>(); + + size += native.numFixedSlots() * sizeof(Value); + size += native.numDynamicSlots() * sizeof(Value); + + if (native.hasDynamicElements()) { + js::ObjectElements& elements = *native.getElementsHeader(); + if (!elements.isCopyOnWrite() || elements.ownerObject() == this) + size += elements.capacity * sizeof(HeapSlot); + } + + if (is<ArgumentsObject>()) + size += as<ArgumentsObject>().sizeOfData(); + } + + return size; +} + +JS::ubi::Node::Size +JS::ubi::Concrete<JSObject>::size(mozilla::MallocSizeOf mallocSizeOf) const +{ + JSObject& obj = get(); + + if (!obj.isTenured()) + return obj.sizeOfIncludingThisInNursery(); + + JS::ClassInfo info; + obj.addSizeOfExcludingThis(mallocSizeOf, &info); + return obj.tenuredSizeOfThis() + info.sizeOfAllThings(); +} + +const char16_t JS::ubi::Concrete<JSObject>::concreteTypeName[] = u"JSObject"; + +void +JSObject::traceChildren(JSTracer* trc) +{ + TraceEdge(trc, &group_, "group"); + + if (is<ShapedObject>()) + as<ShapedObject>().traceShape(trc); + + const Class* clasp = group_->clasp(); + if (clasp->isNative()) { + NativeObject* nobj = &as<NativeObject>(); + + { + GetObjectSlotNameFunctor func(nobj); + JS::AutoTracingDetails ctx(trc, func); + JS::AutoTracingIndex index(trc); + // Tracing can mutate the target but cannot change the slot count, + // but the compiler has no way of knowing this. + const uint32_t nslots = nobj->slotSpan(); + for (uint32_t i = 0; i < nslots; ++i) { + TraceManuallyBarrieredEdge(trc, nobj->getSlotRef(i).unsafeUnbarrieredForTracing(), + "object slot"); + ++index; + } + MOZ_ASSERT(nslots == nobj->slotSpan()); + } + + do { + if (nobj->denseElementsAreCopyOnWrite()) { + GCPtrNativeObject& owner = nobj->getElementsHeader()->ownerObject(); + if (owner != nobj) { + TraceEdge(trc, &owner, "objectElementsOwner"); + break; + } + } + + TraceRange(trc, + nobj->getDenseInitializedLength(), + static_cast<HeapSlot*>(nobj->getDenseElementsAllowCopyOnWrite()), + "objectElements"); + } while (false); + } + + // Call the trace hook at the end so that during a moving GC the trace hook + // will see updated fields and slots. + if (clasp->hasTrace()) + clasp->doTrace(trc, this); +} + +static JSAtom* +displayAtomFromObjectGroup(ObjectGroup& group) +{ + TypeNewScript* script = group.newScript(); + if (!script) + return nullptr; + + return script->function()->displayAtom(); +} + +bool +JSObject::constructorDisplayAtom(JSContext* cx, js::MutableHandleAtom name) +{ + ObjectGroup *g = getGroup(cx); + if (!g) + return false; + + name.set(displayAtomFromObjectGroup(*g)); + return true; +} + +JSAtom* +JSObject::maybeConstructorDisplayAtom() const +{ + if (hasLazyGroup()) + return nullptr; + return displayAtomFromObjectGroup(*group()); +} + +bool +js::SpeciesConstructor(JSContext* cx, HandleObject obj, HandleValue defaultCtor, MutableHandleValue pctor) +{ + HandlePropertyName shName = cx->names().SpeciesConstructor; + RootedValue func(cx); + if (!GlobalObject::getSelfHostedFunction(cx, cx->global(), shName, shName, 2, &func)) + return false; + + FixedInvokeArgs<2> args(cx); + + args[0].setObject(*obj); + args[1].set(defaultCtor); + + if (!Call(cx, func, UndefinedHandleValue, args, pctor)) + return false; + + pctor.set(args.rval()); + return true; +} + +bool +js::SpeciesConstructor(JSContext* cx, HandleObject obj, JSProtoKey ctorKey, + MutableHandleValue pctor) +{ + if (!GlobalObject::ensureConstructor(cx, cx->global(), ctorKey)) + return false; + RootedValue defaultCtor(cx, cx->global()->getConstructor(ctorKey)); + return SpeciesConstructor(cx, obj, defaultCtor, pctor); +} + +bool +js::Unbox(JSContext* cx, HandleObject obj, MutableHandleValue vp) +{ + if (MOZ_UNLIKELY(obj->is<ProxyObject>())) + return Proxy::boxedValue_unbox(cx, obj, vp); + + if (obj->is<BooleanObject>()) + vp.setBoolean(obj->as<BooleanObject>().unbox()); + else if (obj->is<NumberObject>()) + vp.setNumber(obj->as<NumberObject>().unbox()); + else if (obj->is<StringObject>()) + vp.setString(obj->as<StringObject>().unbox()); + else if (obj->is<DateObject>()) + vp.set(obj->as<DateObject>().UTCTime()); + else + vp.setUndefined(); + + return true; +} |