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Mypal/js/src/jsobj.cpp

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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* 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 "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>() && !obj->is<MappedArgumentsObject>())
{
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, &currentDesc))
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 (!JSObject::splicePrototype(cx, res, &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, &regenerate))
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 = JSFunction::getOrCreateScript(cx, callee.as<JSFunction>());
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)
{
return obj->getOpsSetProperty()(cx, obj, id, v, 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(&copyOnWrite))
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);
/* static */ bool
NativeObject::fillInAfterSwap(JSContext* cx, HandleNativeObject obj,
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(obj->slotSpan() == values.length());
// Make sure the shape's numFixedSlots() is correct.
size_t nfixed = gc::GetGCKindSlots(obj->asTenured().getAllocKind(), obj->getClass());
if (nfixed != obj->shape_->numFixedSlots()) {
if (!NativeObject::generateOwnShape(cx, obj))
return false;
obj->shape_->setNumFixedSlots(nfixed);
}
if (obj->hasPrivate())
obj->setPrivate(priv);
else
MOZ_ASSERT(!priv);
if (obj->slots_) {
js_free(obj->slots_);
obj->slots_ = nullptr;
}
if (size_t ndynamic = dynamicSlotsCount(nfixed, values.length(), obj->getClass())) {
obj->slots_ = cx->zone()->pod_malloc<HeapSlot>(ndynamic);
if (!obj->slots_)
return false;
Debug_SetSlotRangeToCrashOnTouch(obj->slots_, ndynamic);
}
obj->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 (!JSObject::getGroup(cx, a))
oomUnsafe.crash("JSObject::swap");
if (!JSObject::getGroup(cx, b))
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) {
if (!NativeObject::fillInAfterSwap(cx, b.as<NativeObject>(), avals, apriv))
oomUnsafe.crash("fillInAfterSwap");
}
if (nb) {
if (!NativeObject::fillInAfterSwap(cx, a.as<NativeObject>(), 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 && !JSObject::splicePrototype(cx, ctor, 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 (!NativeObject::generateOwnShape(cx, oldproto.as<NativeObject>()))
return false;
} else {
if (!JSObject::setUncacheableProto(cx, oldproto))
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()) {
RootedObject protoObj(cx, proto.toObject());
if (!JSObject::setDelegate(cx, protoObj))
return false;
}
if (obj->isSingleton()) {
/*
* Just splice the prototype, but mark the properties as unknown for
* consistent behavior.
*/
if (!JSObject::splicePrototype(cx, obj, 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);
Handle<GlobalObject*> global = globalObj.as<GlobalObject>();
obj.set(GlobalObject::getOrCreateObjectPrototype(cx, global));
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);
Rooted<DebugEnvironmentProxy*> envProxy(cx, &env->as<DebugEnvironmentProxy>());
if (!DebugEnvironmentProxy::getMaybeSentinelValue(cx, envProxy, 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, jsid id, Shape* shape, Value* vp)
{
if (IsImplicitDenseOrTypedArrayElement(shape)) {
// For simplicity we ignore the TypedArray with string index case.
if (!JSID_IS_INT(id))
return false;
*vp = pobj->getDenseOrTypedArrayElement(JSID_TO_INT(id));
return true;
}
// 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>(), id, shape, vp);
}
static inline bool
NativeGetGetterPureInline(Shape* shape, JSFunction** fp)
{
if (!IsImplicitDenseOrTypedArrayElement(shape) && 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;
}
/* static */ 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);
}
/* static */ 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);
}
/* static */ bool
JSObject::reportNotExtensible(JSContext* cx, HandleObject obj, unsigned report)
{
RootedValue val(cx, ObjectValue(*obj));
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>()) {
Handle<GlobalObject*> global = 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 (!JSObject::setFlags(cx, obj, 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 (!JSObject::setFlags(cx, obj, 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;
}
const char*
js::GetObjectClassName(JSContext* cx, HandleObject obj)
{
assertSameCompartment(cx, obj);
if (obj->is<ProxyObject>())
return Proxy::className(cx, obj);
return obj->getClass()->name;
}
/* * */
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;
if (StandardProtoKeyOrNull(obj) == JSProto_Array && id == NameToId(cx->names().values)) {
if (!cx->options().arrayProtoValues())
return true;
}
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 (HasNativeMethodPure(nobj, cx->names().toString, str_toString, cx)) {
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 (HasNativeMethodPure(nobj, cx->names().valueOf, str_toString, cx)) {
vp.setString(nobj->unbox());
return true;
}
}
/* Optimize new Number(...).valueOf(). */
if (clasp == &NumberObject::class_) {
NumberObject* nobj = &obj->as<NumberObject>();
if (HasNativeMethodPure(nobj, cx->names().valueOf, num_valueOf, cx)) {
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**");
}
}
}
/*** 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->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();
}
/* static */ bool
JSObject::constructorDisplayAtom(JSContext* cx, js::HandleObject obj, js::MutableHandleAtom name)
{
ObjectGroup *g = JSObject::getGroup(cx, obj);
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;
}
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