The Tor Browser: js/src/jsobj.h@b8a032363ba2 (annotated)

js/src/jsobj.h@b8a032363ba2 (annotated)

js/src/jsobj.h

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
  * vim: set ts=8 sts=4 et sw=4 tw=99:
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 #ifndef jsobj_h
 #define jsobj_h
 /*
  * JS object definitions.
  *
  * A JS object consists of a possibly-shared object descriptor containing
  * ordered property names, called the map; and a dense vector of property
  * values, called slots.  The map/slot pointer pair is GC'ed, while the map
  * is reference counted and the slot vector is malloc'ed.
  */
 #include "mozilla/MemoryReporting.h"
 #include "gc/Barrier.h"
 #include "gc/Marking.h"
 #include "js/GCAPI.h"
 #include "vm/ObjectImpl.h"
 #include "vm/Shape.h"
 #include "vm/Xdr.h"
 namespace JS {
 struct ObjectsExtraSizes;
 }
 namespace js {
 class AutoPropDescArrayRooter;
 struct GCMarker;
 struct NativeIterator;
 class Nursery;
 struct StackShape;
 inline JSObject *
 CastAsObject(PropertyOp op)
 {
     return JS_FUNC_TO_DATA_PTR(JSObject *, op);
 }
 inline JSObject *
 CastAsObject(StrictPropertyOp op)
 {
     return JS_FUNC_TO_DATA_PTR(JSObject *, op);
 }
 inline Value
 CastAsObjectJsval(PropertyOp op)
 {
     return ObjectOrNullValue(CastAsObject(op));
 }
 inline Value
 CastAsObjectJsval(StrictPropertyOp op)
 {
     return ObjectOrNullValue(CastAsObject(op));
 }
 /******************************************************************************/
 typedef Vector<PropDesc, 1> PropDescArray;
 /*
  * The baseops namespace encapsulates the default behavior when performing
  * various operations on an object, irrespective of hooks installed in the
  * object's class. In general, instance methods on the object itself should be
  * called instead of calling these methods directly.
  */
 namespace baseops {
 /*
  * On success, and if id was found, return true with *objp non-null and with a
  * property of *objp stored in *propp. If successful but id was not found,
  * return true with both *objp and *propp null.
  */
 template <AllowGC allowGC>
 extern bool
 LookupProperty(ExclusiveContext *cx,
                typename MaybeRooted<JSObject*, allowGC>::HandleType obj,
                typename MaybeRooted<jsid, allowGC>::HandleType id,
                typename MaybeRooted<JSObject*, allowGC>::MutableHandleType objp,
                typename MaybeRooted<Shape*, allowGC>::MutableHandleType propp);
 extern bool
 LookupElement(JSContext *cx, HandleObject obj, uint32_t index,
               MutableHandleObject objp, MutableHandleShape propp);
 extern bool
 DefineGeneric(ExclusiveContext *cx, HandleObject obj, HandleId id, HandleValue value,
                JSPropertyOp getter, JSStrictPropertyOp setter, unsigned attrs);
 extern bool
 DefineElement(ExclusiveContext *cx, HandleObject obj, uint32_t index, HandleValue value,
               JSPropertyOp getter, JSStrictPropertyOp setter, unsigned attrs);
 extern bool
 GetProperty(JSContext *cx, HandleObject obj, HandleObject receiver, HandleId id, MutableHandleValue vp);
 extern bool
 GetPropertyNoGC(JSContext *cx, JSObject *obj, JSObject *receiver, jsid id, Value *vp);
 extern bool
 GetElement(JSContext *cx, HandleObject obj, HandleObject receiver, uint32_t index, MutableHandleValue vp);
 inline bool
 GetProperty(JSContext *cx, HandleObject obj, HandleId id, MutableHandleValue vp)
 {
     return GetProperty(cx, obj, obj, id, vp);
 }
 inline bool
 GetElement(JSContext *cx, HandleObject obj, uint32_t index, MutableHandleValue vp)
 {
     return GetElement(cx, obj, obj, index, vp);
 }
 /*
  * Indicates whether an assignment operation is qualified (`x.y = 0`) or
  * unqualified (`y = 0`). In strict mode, the latter is an error if no such
  * variable already exists.
  *
  * Used as an argument to baseops::SetPropertyHelper.
  */
 enum QualifiedBool {
     Unqualified = 0,
     Qualified = 1
 };
 template <ExecutionMode mode>
 extern bool
 SetPropertyHelper(typename ExecutionModeTraits<mode>::ContextType cx, HandleObject obj,
                   HandleObject receiver, HandleId id, QualifiedBool qualified,
                   MutableHandleValue vp, bool strict);
 extern bool
 SetElementHelper(JSContext *cx, HandleObject obj, HandleObject Receiver, uint32_t index,
                  MutableHandleValue vp, bool strict);
 extern bool
 GetAttributes(JSContext *cx, HandleObject obj, HandleId id, unsigned *attrsp);
 extern bool
 SetAttributes(JSContext *cx, HandleObject obj, HandleId id, unsigned *attrsp);
 extern bool
 DeleteProperty(JSContext *cx, HandleObject obj, HandlePropertyName name, bool *succeeded);
 extern bool
 DeleteElement(JSContext *cx, HandleObject obj, uint32_t index, bool *succeeded);
 extern bool
 DeleteGeneric(JSContext *cx, HandleObject obj, HandleId id, bool *succeeded);
 extern bool
 Watch(JSContext *cx, JS::HandleObject obj, JS::HandleId id, JS::HandleObject callable);
 extern bool
 Unwatch(JSContext *cx, JS::HandleObject obj, JS::HandleId id);
 } /* namespace js::baseops */
 extern const Class IntlClass;
 extern const Class JSONClass;
 extern const Class MathClass;
 class GlobalObject;
 class MapObject;
 class NewObjectCache;
 class NormalArgumentsObject;
 class SetObject;
 class StrictArgumentsObject;
 /*
  * NOTE: This is a placeholder for bug 619558.
  *
  * Run a post write barrier that encompasses multiple contiguous slots in a
  * single step.
  */
 inline void
 DenseRangeWriteBarrierPost(JSRuntime *rt, JSObject *obj, uint32_t start, uint32_t count)
 {
 #ifdef JSGC_GENERATIONAL
     if (count > 0) {
         JS::shadow::Runtime *shadowRuntime = JS::shadow::Runtime::asShadowRuntime(rt);
         shadowRuntime->gcStoreBufferPtr()->putSlot(obj, HeapSlot::Element, start, count);
     }
 #endif
 }
 }  /* namespace js */
 /*
  * The public interface for an object.
  *
  * Implementation of the underlying structure occurs in ObjectImpl, from which
  * this struct inherits.  This inheritance is currently public, but it will
  * eventually be made protected.  For full details, see vm/ObjectImpl.{h,cpp}.
  *
  * The JSFunction struct is an extension of this struct allocated from a larger
  * GC size-class.
  */
 class JSObject : public js::ObjectImpl
 {
   private:
     friend class js::Shape;
     friend struct js::GCMarker;
     friend class  js::NewObjectCache;
     friend class js::Nursery;
     /* Make the type object to use for LAZY_TYPE objects. */
     static js::types::TypeObject *makeLazyType(JSContext *cx, js::HandleObject obj);
   public:
     static const js::Class class_;
     /*
      * Update the last property, keeping the number of allocated slots in sync
      * with the object's new slot span.
      */
     static bool setLastProperty(js::ThreadSafeContext *cx,
                                 JS::HandleObject obj, js::HandleShape shape);
     /* As above, but does not change the slot span. */
     inline void setLastPropertyInfallible(js::Shape *shape);
     /*
      * Make a non-array object with the specified initial state. This method
      * takes ownership of any extantSlots it is passed.
      */
     static inline JSObject *create(js::ExclusiveContext *cx,
                                    js::gc::AllocKind kind,
                                    js::gc::InitialHeap heap,
                                    js::HandleShape shape,
                                    js::HandleTypeObject type,
                                    js::HeapSlot *extantSlots = nullptr);
     /* Make an array object with the specified initial state. */
     static inline js::ArrayObject *createArray(js::ExclusiveContext *cx,
                                                js::gc::AllocKind kind,
                                                js::gc::InitialHeap heap,
                                                js::HandleShape shape,
                                                js::HandleTypeObject type,
                                                uint32_t length);
     /*
      * Remove the last property of an object, provided that it is safe to do so
      * (the shape and previous shape do not carry conflicting information about
      * the object itself).
      */
     inline void removeLastProperty(js::ExclusiveContext *cx);
     inline bool canRemoveLastProperty();
     /*
      * Update the slot span directly for a dictionary object, and allocate
      * slots to cover the new span if necessary.
      */
     static bool setSlotSpan(js::ThreadSafeContext *cx, JS::HandleObject obj, uint32_t span);
     /* Upper bound on the number of elements in an object. */
     static const uint32_t NELEMENTS_LIMIT = JS_BIT(28);
   public:
     bool setDelegate(js::ExclusiveContext *cx) {
         return setFlag(cx, js::BaseShape::DELEGATE, GENERATE_SHAPE);
     }
     bool isBoundFunction() const {
         return lastProperty()->hasObjectFlag(js::BaseShape::BOUND_FUNCTION);
     }
     inline bool hasSpecialEquality() const;
     bool watched() const {
         return lastProperty()->hasObjectFlag(js::BaseShape::WATCHED);
     }
     bool setWatched(js::ExclusiveContext *cx) {
         return setFlag(cx, js::BaseShape::WATCHED, GENERATE_SHAPE);
     }
     /* See InterpreterFrame::varObj. */
     inline bool isVarObj();
     bool setVarObj(js::ExclusiveContext *cx) {
         return setFlag(cx, js::BaseShape::VAROBJ);
     }
     /*
      * Objects with an uncacheable proto can have their prototype mutated
      * without inducing a shape change on the object. Property cache entries
      * and JIT inline caches should not be filled for lookups across prototype
      * lookups on the object.
      */
     bool hasUncacheableProto() const {
         return lastProperty()->hasObjectFlag(js::BaseShape::UNCACHEABLE_PROTO);
     }
     bool setUncacheableProto(js::ExclusiveContext *cx) {
         return setFlag(cx, js::BaseShape::UNCACHEABLE_PROTO, GENERATE_SHAPE);
     }
     /*
      * Whether SETLELEM was used to access this object. See also the comment near
      * PropertyTree::MAX_HEIGHT.
      */
     bool hadElementsAccess() const {
         return lastProperty()->hasObjectFlag(js::BaseShape::HAD_ELEMENTS_ACCESS);
     }
     bool setHadElementsAccess(js::ExclusiveContext *cx) {
         return setFlag(cx, js::BaseShape::HAD_ELEMENTS_ACCESS);
     }
   public:
     bool nativeEmpty() const {
         return lastProperty()->isEmptyShape();
     }
     bool shadowingShapeChange(js::ExclusiveContext *cx, const js::Shape &shape);
     /*
      * Whether there may be indexed properties on this object, excluding any in
      * the object's elements.
      */
     bool isIndexed() const {
         return lastProperty()->hasObjectFlag(js::BaseShape::INDEXED);
     }
     uint32_t propertyCount() const {
         return lastProperty()->entryCount();
     }
     bool hasShapeTable() const {
         return lastProperty()->hasTable();
     }
     void addSizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf, JS::ObjectsExtraSizes *sizes);
     bool hasIdempotentProtoChain() const;
     // MAX_FIXED_SLOTS is the biggest number of fixed slots our GC
     // size classes will give an object.
     static const uint32_t MAX_FIXED_SLOTS = 16;
   public:
     /* Accessors for properties. */
     /* Whether a slot is at a fixed offset from this object. */
     bool isFixedSlot(size_t slot) {
         return slot < numFixedSlots();
     }
     /* Index into the dynamic slots array to use for a dynamic slot. */
     size_t dynamicSlotIndex(size_t slot) {
         JS_ASSERT(slot >= numFixedSlots());
         return slot - numFixedSlots();
     }
     /*
      * Grow or shrink slots immediately before changing the slot span.
      * The number of allocated slots is not stored explicitly, and changes to
      * the slots must track changes in the slot span.
      */
     static bool growSlots(js::ThreadSafeContext *cx, js::HandleObject obj, uint32_t oldCount,
                           uint32_t newCount);
     static void shrinkSlots(js::ThreadSafeContext *cx, js::HandleObject obj, uint32_t oldCount,
                             uint32_t newCount);
     bool hasDynamicSlots() const { return !!slots; }
   protected:
     static inline bool updateSlotsForSpan(js::ThreadSafeContext *cx,
                                           js::HandleObject obj, size_t oldSpan, size_t newSpan);
   public:
     /*
      * Trigger the write barrier on a range of slots that will no longer be
      * reachable.
      */
     void prepareSlotRangeForOverwrite(size_t start, size_t end) {
         for (size_t i = start; i < end; i++)
             getSlotAddressUnchecked(i)->js::HeapSlot::~HeapSlot();
     }
     void prepareElementRangeForOverwrite(size_t start, size_t end) {
         JS_ASSERT(end <= getDenseInitializedLength());
         for (size_t i = start; i < end; i++)
             elements[i].js::HeapSlot::~HeapSlot();
     }
     static bool rollbackProperties(js::ExclusiveContext *cx, js::HandleObject obj,
                                    uint32_t slotSpan);
     void nativeSetSlot(uint32_t slot, const js::Value &value) {
         JS_ASSERT(isNative());
         JS_ASSERT(slot < slotSpan());
         return setSlot(slot, value);
     }
     inline bool nativeSetSlotIfHasType(js::Shape *shape, const js::Value &value);
     inline void nativeSetSlotWithType(js::ExclusiveContext *cx, js::Shape *shape,
                                       const js::Value &value);
     inline const js::Value &getReservedSlot(uint32_t index) const {
         JS_ASSERT(index < JSSLOT_FREE(getClass()));
         return getSlot(index);
     }
     const js::HeapSlot &getReservedSlotRef(uint32_t index) const {
         JS_ASSERT(index < JSSLOT_FREE(getClass()));
         return getSlotRef(index);
     }
     js::HeapSlot &getReservedSlotRef(uint32_t index) {
         JS_ASSERT(index < JSSLOT_FREE(getClass()));
         return getSlotRef(index);
     }
     void initReservedSlot(uint32_t index, const js::Value &v) {
         JS_ASSERT(index < JSSLOT_FREE(getClass()));
         initSlot(index, v);
     }
     void setReservedSlot(uint32_t index, const js::Value &v) {
         JS_ASSERT(index < JSSLOT_FREE(getClass()));
         setSlot(index, v);
     }
     /*
      * Marks this object as having a singleton type, and leave the type lazy.
      * Constructs a new, unique shape for the object.
      */
     static inline bool setSingletonType(js::ExclusiveContext *cx, js::HandleObject obj);
     // uninlinedGetType() is the same as getType(), but not inlined.
     inline js::types::TypeObject* getType(JSContext *cx);
     js::types::TypeObject* uninlinedGetType(JSContext *cx);
     const js::HeapPtr<js::types::TypeObject> &typeFromGC() const {
         /* Direct field access for use by GC. */
         return type_;
     }
     /*
      * We allow the prototype of an object to be lazily computed if the object
      * is a proxy. In the lazy case, we store (JSObject *)0x1 in the proto field
      * of the object's TypeObject. We offer three ways of getting the prototype:
      *
      * 1. obj->getProto() returns the prototype, but asserts if obj is a proxy.
      * 2. obj->getTaggedProto() returns a TaggedProto, which can be tested to
      *    check if the proto is an object, nullptr, or lazily computed.
      * 3. JSObject::getProto(cx, obj, &proto) computes the proto of an object.
      *    If obj is a proxy and the proto is lazy, this code may allocate or
      *    GC in order to compute the proto. Currently, it will not run JS code.
      */
     bool uninlinedIsProxy() const;
     JSObject *getProto() const {
         JS_ASSERT(!uninlinedIsProxy());
         return getTaggedProto().toObjectOrNull();
     }
     static inline bool getProto(JSContext *cx, js::HandleObject obj,
                                 js::MutableHandleObject protop);
     // Returns false on error, success of operation in outparam.
     static inline bool setProto(JSContext *cx, JS::HandleObject obj,
                                 JS::HandleObject proto, bool *succeeded);
     // uninlinedSetType() is the same as setType(), but not inlined.
     inline void setType(js::types::TypeObject *newType);
     void uninlinedSetType(js::types::TypeObject *newType);
 #ifdef DEBUG
     bool hasNewType(const js::Class *clasp, js::types::TypeObject *newType);
 #endif
     /*
      * Mark an object that has been iterated over and is a singleton. We need
      * to recover this information in the object's type information after it
      * is purged on GC.
      */
     bool isIteratedSingleton() const {
         return lastProperty()->hasObjectFlag(js::BaseShape::ITERATED_SINGLETON);
     }
     bool setIteratedSingleton(js::ExclusiveContext *cx) {
         return setFlag(cx, js::BaseShape::ITERATED_SINGLETON);
     }
     /*
      * Mark an object as requiring its default 'new' type to have unknown
      * properties.
      */
     bool isNewTypeUnknown() const {
         return lastProperty()->hasObjectFlag(js::BaseShape::NEW_TYPE_UNKNOWN);
     }
     static bool setNewTypeUnknown(JSContext *cx, const js::Class *clasp, JS::HandleObject obj);
     /* Set a new prototype for an object with a singleton type. */
     bool splicePrototype(JSContext *cx, const js::Class *clasp, js::Handle<js::TaggedProto> proto);
     /*
      * For bootstrapping, whether to splice a prototype for Function.prototype
      * or the global object.
      */
     bool shouldSplicePrototype(JSContext *cx);
     /*
      * Parents and scope chains.
      *
      * All script-accessible objects with a nullptr parent are global objects,
      * and all global objects have a nullptr parent. Some builtin objects
      * which are not script-accessible also have a nullptr parent, such as
      * parser created functions for non-compileAndGo scripts.
      *
      * Except for the non-script-accessible builtins, the global with which an
      * object is associated can be reached by following parent links to that
      * global (see global()).
      *
      * The scope chain of an object is the link in the search path when a
      * script does a name lookup on a scope object. For JS internal scope
      * objects --- Call, DeclEnv and Block --- the chain is stored in
      * the first fixed slot of the object, and the object's parent is the
      * associated global. For other scope objects, the chain is stored in the
      * object's parent.
      *
      * In compileAndGo code, scope chains can contain only internal scope
      * objects with a global object at the root as the scope of the outermost
      * non-function script. In non-compileAndGo code, the scope of the
      * outermost non-function script might not be a global object, and can have
      * a mix of other objects above it before the global object is reached.
      */
     /* Access the parent link of an object. */
     JSObject *getParent() const {
         return lastProperty()->getObjectParent();
     }
     static bool setParent(JSContext *cx, js::HandleObject obj, js::HandleObject newParent);
     /*
      * Get the enclosing scope of an object. When called on non-scope object,
      * this will just be the global (the name "enclosing scope" still applies
      * in this situation because non-scope objects can be on the scope chain).
      */
     inline JSObject *enclosingScope();
     /* Access the metadata on an object. */
     inline JSObject *getMetadata() const {
         return lastProperty()->getObjectMetadata();
     }
     static bool setMetadata(JSContext *cx, js::HandleObject obj, js::HandleObject newMetadata);
     inline js::GlobalObject &global() const;
     inline bool isOwnGlobal() const;
     /* Remove the type (and prototype) or parent from a new object. */
     static inline bool clearType(JSContext *cx, js::HandleObject obj);
     static bool clearParent(JSContext *cx, js::HandleObject obj);
     /*
      * ES5 meta-object properties and operations.
      */
   private:
     enum ImmutabilityType { SEAL, FREEZE };
     /*
      * The guts of Object.seal (ES5 15.2.3.8) and Object.freeze (ES5 15.2.3.9): mark the
      * object as non-extensible, and adjust each property's attributes appropriately: each
      * property becomes non-configurable, and if |freeze|, data properties become
      * read-only as well.
      */
     static bool sealOrFreeze(JSContext *cx, js::HandleObject obj, ImmutabilityType it);
     static bool isSealedOrFrozen(JSContext *cx, js::HandleObject obj, ImmutabilityType it, bool *resultp);
     static inline unsigned getSealedOrFrozenAttributes(unsigned attrs, ImmutabilityType it);
   public:
     /* ES5 15.2.3.8: non-extensible, all props non-configurable */
     static inline bool seal(JSContext *cx, js::HandleObject obj) { return sealOrFreeze(cx, obj, SEAL); }
     /* ES5 15.2.3.9: non-extensible, all properties non-configurable, all data props read-only */
     static inline bool freeze(JSContext *cx, js::HandleObject obj) { return sealOrFreeze(cx, obj, FREEZE); }
     static inline bool isSealed(JSContext *cx, js::HandleObject obj, bool *resultp) {
         return isSealedOrFrozen(cx, obj, SEAL, resultp);
     }
     static inline bool isFrozen(JSContext *cx, js::HandleObject obj, bool *resultp) {
         return isSealedOrFrozen(cx, obj, FREEZE, resultp);
     }
     /* toString support. */
     static const char *className(JSContext *cx, js::HandleObject obj);
     /* Accessors for elements. */
     bool ensureElements(js::ThreadSafeContext *cx, uint32_t capacity) {
         if (capacity > getDenseCapacity())
             return growElements(cx, capacity);
         return true;
     }
     bool growElements(js::ThreadSafeContext *cx, uint32_t newcap);
     void shrinkElements(js::ThreadSafeContext *cx, uint32_t cap);
     void setDynamicElements(js::ObjectElements *header) {
         JS_ASSERT(!hasDynamicElements());
         elements = header->elements();
         JS_ASSERT(hasDynamicElements());
     }
     uint32_t getDenseCapacity() {
         JS_ASSERT(isNative());
         JS_ASSERT(getElementsHeader()->capacity >= getElementsHeader()->initializedLength);
         return getElementsHeader()->capacity;
     }
   private:
     inline void ensureDenseInitializedLengthNoPackedCheck(js::ThreadSafeContext *cx,
                                                           uint32_t index, uint32_t extra);
   public:
     void setDenseInitializedLength(uint32_t length) {
         JS_ASSERT(isNative());
         JS_ASSERT(length <= getDenseCapacity());
         prepareElementRangeForOverwrite(length, getElementsHeader()->initializedLength);
         getElementsHeader()->initializedLength = length;
     }
     inline void ensureDenseInitializedLength(js::ExclusiveContext *cx,
                                              uint32_t index, uint32_t extra);
     inline void ensureDenseInitializedLengthPreservePackedFlag(js::ThreadSafeContext *cx,
                                                                uint32_t index, uint32_t extra);
     void setDenseElement(uint32_t index, const js::Value &val) {
         JS_ASSERT(isNative() && index < getDenseInitializedLength());
         elements[index].set(this, js::HeapSlot::Element, index, val);
     }
     void initDenseElement(uint32_t index, const js::Value &val) {
         JS_ASSERT(isNative() && index < getDenseInitializedLength());
         elements[index].init(this, js::HeapSlot::Element, index, val);
     }
     void setDenseElementMaybeConvertDouble(uint32_t index, const js::Value &val) {
         if (val.isInt32() && shouldConvertDoubleElements())
             setDenseElement(index, js::DoubleValue(val.toInt32()));
         else
             setDenseElement(index, val);
     }
     inline bool setDenseElementIfHasType(uint32_t index, const js::Value &val);
     inline void setDenseElementWithType(js::ExclusiveContext *cx, uint32_t index,
                                         const js::Value &val);
     inline void initDenseElementWithType(js::ExclusiveContext *cx, uint32_t index,
                                          const js::Value &val);
     inline void setDenseElementHole(js::ExclusiveContext *cx, uint32_t index);
     static inline void removeDenseElementForSparseIndex(js::ExclusiveContext *cx,
                                                         js::HandleObject obj, uint32_t index);
     inline js::Value getDenseOrTypedArrayElement(uint32_t idx);
     void copyDenseElements(uint32_t dstStart, const js::Value *src, uint32_t count) {
         JS_ASSERT(dstStart + count <= getDenseCapacity());
         JSRuntime *rt = runtimeFromMainThread();
         if (JS::IsIncrementalBarrierNeeded(rt)) {
             JS::Zone *zone = this->zone();
             for (uint32_t i = 0; i < count; ++i)
                 elements[dstStart + i].set(zone, this, js::HeapSlot::Element, dstStart + i, src[i]);
         } else {
             memcpy(&elements[dstStart], src, count * sizeof(js::HeapSlot));
             DenseRangeWriteBarrierPost(rt, this, dstStart, count);
         }
     }
     void initDenseElements(uint32_t dstStart, const js::Value *src, uint32_t count) {
         JS_ASSERT(dstStart + count <= getDenseCapacity());
         memcpy(&elements[dstStart], src, count * sizeof(js::HeapSlot));
         DenseRangeWriteBarrierPost(runtimeFromMainThread(), this, dstStart, count);
     }
     void initDenseElementsUnbarriered(uint32_t dstStart, const js::Value *src, uint32_t count) {
         /*
          * For use by parallel threads, which since they cannot see nursery
          * things do not require a barrier.
          */
         JS_ASSERT(dstStart + count <= getDenseCapacity());
 #if defined(DEBUG) && defined(JSGC_GENERATIONAL)
         JS::shadow::Runtime *rt = JS::shadow::Runtime::asShadowRuntime(runtimeFromAnyThread());
         JS_ASSERT(!js::gc::IsInsideNursery(rt, this));
         for (uint32_t index = 0; index < count; ++index) {
             const JS::Value& value = src[index];
             if (value.isMarkable())
                 JS_ASSERT(!js::gc::IsInsideNursery(rt, value.toGCThing()));
         }
 #endif
         memcpy(&elements[dstStart], src, count * sizeof(js::HeapSlot));
     }
     void moveDenseElements(uint32_t dstStart, uint32_t srcStart, uint32_t count) {
         JS_ASSERT(dstStart + count <= getDenseCapacity());
         JS_ASSERT(srcStart + count <= getDenseInitializedLength());
         /*
          * Using memmove here would skip write barriers. Also, we need to consider
          * an array containing [A, B, C], in the following situation:
          *
          * 1. Incremental GC marks slot 0 of array (i.e., A), then returns to JS code.
          * 2. JS code moves slots 1..2 into slots 0..1, so it contains [B, C, C].
          * 3. Incremental GC finishes by marking slots 1 and 2 (i.e., C).
          *
          * Since normal marking never happens on B, it is very important that the
          * write barrier is invoked here on B, despite the fact that it exists in
          * the array before and after the move.
         */
         JS::Zone *zone = this->zone();
         JS::shadow::Zone *shadowZone = JS::shadow::Zone::asShadowZone(zone);
         if (shadowZone->needsBarrier()) {
             if (dstStart < srcStart) {
                 js::HeapSlot *dst = elements + dstStart;
                 js::HeapSlot *src = elements + srcStart;
                 for (uint32_t i = 0; i < count; i++, dst++, src++)
                     dst->set(zone, this, js::HeapSlot::Element, dst - elements, *src);
             } else {
                 js::HeapSlot *dst = elements + dstStart + count - 1;
                 js::HeapSlot *src = elements + srcStart + count - 1;
                 for (uint32_t i = 0; i < count; i++, dst--, src--)
                     dst->set(zone, this, js::HeapSlot::Element, dst - elements, *src);
             }
         } else {
             memmove(elements + dstStart, elements + srcStart, count * sizeof(js::HeapSlot));
             DenseRangeWriteBarrierPost(runtimeFromMainThread(), this, dstStart, count);
         }
     }
     void moveDenseElementsNoPreBarrier(uint32_t dstStart, uint32_t srcStart, uint32_t count) {
         JS_ASSERT(!shadowZone()->needsBarrier());
         JS_ASSERT(dstStart + count <= getDenseCapacity());
         JS_ASSERT(srcStart + count <= getDenseCapacity());
         memmove(elements + dstStart, elements + srcStart, count * sizeof(js::Value));
         DenseRangeWriteBarrierPost(runtimeFromMainThread(), this, dstStart, count);
     }
     bool shouldConvertDoubleElements() {
         JS_ASSERT(getClass()->isNative());
         return getElementsHeader()->shouldConvertDoubleElements();
     }
     inline void setShouldConvertDoubleElements();
     inline void clearShouldConvertDoubleElements();
     /* Packed information for this object's elements. */
     inline bool writeToIndexWouldMarkNotPacked(uint32_t index);
     inline void markDenseElementsNotPacked(js::ExclusiveContext *cx);
     /*
      * ensureDenseElements ensures that the object can hold at least
      * index + extra elements. It returns ED_OK on success, ED_FAILED on
      * failure to grow the array, ED_SPARSE when the object is too sparse to
      * grow (this includes the case of index + extra overflow). In the last
      * two cases the object is kept intact.
      */
     enum EnsureDenseResult { ED_OK, ED_FAILED, ED_SPARSE };
   private:
     inline EnsureDenseResult ensureDenseElementsNoPackedCheck(js::ThreadSafeContext *cx,
                                                               uint32_t index, uint32_t extra);
   public:
     inline EnsureDenseResult ensureDenseElements(js::ExclusiveContext *cx,
                                                  uint32_t index, uint32_t extra);
     inline EnsureDenseResult ensureDenseElementsPreservePackedFlag(js::ThreadSafeContext *cx,
                                                                    uint32_t index, uint32_t extra);
     inline EnsureDenseResult extendDenseElements(js::ThreadSafeContext *cx,
                                                  uint32_t requiredCapacity, uint32_t extra);
     /* Convert a single dense element to a sparse property. */
     static bool sparsifyDenseElement(js::ExclusiveContext *cx,
                                      js::HandleObject obj, uint32_t index);
     /* Convert all dense elements to sparse properties. */
     static bool sparsifyDenseElements(js::ExclusiveContext *cx, js::HandleObject obj);
     /* Small objects are dense, no matter what. */
     static const uint32_t MIN_SPARSE_INDEX = 1000;
     /*
      * Element storage for an object will be sparse if fewer than 1/8 indexes
      * are filled in.
      */
     static const unsigned SPARSE_DENSITY_RATIO = 8;
     /*
      * Check if after growing the object's elements will be too sparse.
      * newElementsHint is an estimated number of elements to be added.
      */
     bool willBeSparseElements(uint32_t requiredCapacity, uint32_t newElementsHint);
     /*
      * After adding a sparse index to obj, see if it should be converted to use
      * dense elements.
      */
     static EnsureDenseResult maybeDensifySparseElements(js::ExclusiveContext *cx, js::HandleObject obj);
   public:
     /*
      * Iterator-specific getters and setters.
      */
     static const uint32_t ITER_CLASS_NFIXED_SLOTS = 1;
     /*
      * Back to generic stuff.
      */
     bool isCallable() {
         return getClass()->isCallable();
     }
     inline void finish(js::FreeOp *fop);
     MOZ_ALWAYS_INLINE void finalize(js::FreeOp *fop);
     static inline bool hasProperty(JSContext *cx, js::HandleObject obj,
                                    js::HandleId id, bool *foundp);
     /*
      * Allocate and free an object slot.
      *
      * FIXME: bug 593129 -- slot allocation should be done by object methods
      * after calling object-parameter-free shape methods, avoiding coupling
      * logic across the object vs. shape module wall.
      */
     static bool allocSlot(js::ThreadSafeContext *cx, JS::HandleObject obj, uint32_t *slotp);
     void freeSlot(uint32_t slot);
   public:
     static bool reportReadOnly(js::ThreadSafeContext *cx, jsid id, unsigned report = JSREPORT_ERROR);
     bool reportNotConfigurable(js::ThreadSafeContext *cx, jsid id, unsigned report = JSREPORT_ERROR);
     bool reportNotExtensible(js::ThreadSafeContext *cx, unsigned report = JSREPORT_ERROR);
     /*
      * Get the property with the given id, then call it as a function with the
      * given arguments, providing this object as |this|. If the property isn't
      * callable a TypeError will be thrown. On success the value returned by
      * the call is stored in *vp.
      */
     bool callMethod(JSContext *cx, js::HandleId id, unsigned argc, js::Value *argv,
                     js::MutableHandleValue vp);
   private:
     static js::Shape *getChildPropertyOnDictionary(js::ThreadSafeContext *cx, JS::HandleObject obj,
                                                    js::HandleShape parent, js::StackShape &child);
     static js::Shape *getChildProperty(js::ExclusiveContext *cx, JS::HandleObject obj,
                                        js::HandleShape parent, js::StackShape &child);
     template <js::ExecutionMode mode>
     static inline js::Shape *
     getOrLookupChildProperty(typename js::ExecutionModeTraits<mode>::ExclusiveContextType cx,
                              JS::HandleObject obj, js::HandleShape parent, js::StackShape &child)
     {
         if (mode == js::ParallelExecution)
             return lookupChildProperty(cx, obj, parent, child);
         return getChildProperty(cx->asExclusiveContext(), obj, parent, child);
     }
   public:
     /*
      * XXX: This should be private, but is public because it needs to be a
      * friend of ThreadSafeContext to get to the propertyTree on cx->compartment_.
      */
     static js::Shape *lookupChildProperty(js::ThreadSafeContext *cx, JS::HandleObject obj,
                                           js::HandleShape parent, js::StackShape &child);
   protected:
     /*
      * Internal helper that adds a shape not yet mapped by this object.
      *
      * Notes:
      * 1. getter and setter must be normalized based on flags (see jsscope.cpp).
      * 2. Checks for non-extensibility must be done by callers.
      */
     template <js::ExecutionMode mode>
     static js::Shape *
     addPropertyInternal(typename js::ExecutionModeTraits<mode>::ExclusiveContextType cx,
                         JS::HandleObject obj, JS::HandleId id,
                         JSPropertyOp getter, JSStrictPropertyOp setter,
                         uint32_t slot, unsigned attrs, unsigned flags, js::Shape **spp,
                         bool allowDictionary);
   private:
     struct TradeGutsReserved;
     static bool ReserveForTradeGuts(JSContext *cx, JSObject *a, JSObject *b,
                                     TradeGutsReserved &reserved);
     static void TradeGuts(JSContext *cx, JSObject *a, JSObject *b,
                           TradeGutsReserved &reserved);
   public:
     /* Add a property whose id is not yet in this scope. */
     static js::Shape *addProperty(js::ExclusiveContext *cx, JS::HandleObject, JS::HandleId id,
                                   JSPropertyOp getter, JSStrictPropertyOp setter,
                                   uint32_t slot, unsigned attrs, unsigned flags,
                                   bool allowDictionary = true);
     /* Add a data property whose id is not yet in this scope. */
     js::Shape *addDataProperty(js::ExclusiveContext *cx,
                                jsid id_, uint32_t slot, unsigned attrs);
     js::Shape *addDataProperty(js::ExclusiveContext *cx, js::HandlePropertyName name,
                                uint32_t slot, unsigned attrs);
     /* Add or overwrite a property for id in this scope. */
     template <js::ExecutionMode mode>
     static js::Shape *
     putProperty(typename js::ExecutionModeTraits<mode>::ExclusiveContextType cx,
                 JS::HandleObject obj, JS::HandleId id,
                 JSPropertyOp getter, JSStrictPropertyOp setter,
                 uint32_t slot, unsigned attrs,
                 unsigned flags);
     template <js::ExecutionMode mode>
     static inline js::Shape *
     putProperty(typename js::ExecutionModeTraits<mode>::ExclusiveContextType cx,
                 JS::HandleObject obj, js::PropertyName *name,
                 JSPropertyOp getter, JSStrictPropertyOp setter,
                 uint32_t slot, unsigned attrs,
                 unsigned flags);
     /* Change the given property into a sibling with the same id in this scope. */
     template <js::ExecutionMode mode>
     static js::Shape *
     changeProperty(typename js::ExecutionModeTraits<mode>::ExclusiveContextType cx,
                    js::HandleObject obj, js::HandleShape shape, unsigned attrs, unsigned mask,
                    JSPropertyOp getter, JSStrictPropertyOp setter);
     static inline bool changePropertyAttributes(JSContext *cx, js::HandleObject obj,
                                                 js::HandleShape shape, unsigned attrs);
     /* Remove the property named by id from this object. */
     bool removeProperty(js::ExclusiveContext *cx, jsid id);
     /* Clear the scope, making it empty. */
     static void clear(JSContext *cx, js::HandleObject obj);
     static bool lookupGeneric(JSContext *cx, js::HandleObject obj, js::HandleId id,
                               js::MutableHandleObject objp, js::MutableHandleShape propp);
     static bool lookupProperty(JSContext *cx, js::HandleObject obj, js::PropertyName *name,
                                js::MutableHandleObject objp, js::MutableHandleShape propp)
     {
         JS::RootedId id(cx, js::NameToId(name));
         return lookupGeneric(cx, obj, id, objp, propp);
     }
     static bool lookupElement(JSContext *cx, js::HandleObject obj, uint32_t index,
                               js::MutableHandleObject objp, js::MutableHandleShape propp)
     {
         js::LookupElementOp op = obj->getOps()->lookupElement;
         return (op ? op : js::baseops::LookupElement)(cx, obj, index, objp, propp);
     }
     static bool defineGeneric(js::ExclusiveContext *cx, js::HandleObject obj,
                               js::HandleId id, js::HandleValue value,
                               JSPropertyOp getter = JS_PropertyStub,
                               JSStrictPropertyOp setter = JS_StrictPropertyStub,
                               unsigned attrs = JSPROP_ENUMERATE);
     static bool defineProperty(js::ExclusiveContext *cx, js::HandleObject obj,
                                js::PropertyName *name, js::HandleValue value,
                                JSPropertyOp getter = JS_PropertyStub,
                                JSStrictPropertyOp setter = JS_StrictPropertyStub,
                                unsigned attrs = JSPROP_ENUMERATE);
     static bool defineElement(js::ExclusiveContext *cx, js::HandleObject obj,
                               uint32_t index, js::HandleValue value,
                               JSPropertyOp getter = JS_PropertyStub,
                               JSStrictPropertyOp setter = JS_StrictPropertyStub,
                               unsigned attrs = JSPROP_ENUMERATE);
     static bool getGeneric(JSContext *cx, js::HandleObject obj, js::HandleObject receiver,
                            js::HandleId id, js::MutableHandleValue vp)
     {
         JS_ASSERT(!!obj->getOps()->getGeneric == !!obj->getOps()->getProperty);
         js::GenericIdOp op = obj->getOps()->getGeneric;
         if (op) {
             if (!op(cx, obj, receiver, id, vp))
                 return false;
         } else {
             if (!js::baseops::GetProperty(cx, obj, receiver, id, vp))
                 return false;
         }
         return true;
     }
     static bool getGenericNoGC(JSContext *cx, JSObject *obj, JSObject *receiver,
                                jsid id, js::Value *vp)
     {
         js::GenericIdOp op = obj->getOps()->getGeneric;
         if (op)
             return false;
         return js::baseops::GetPropertyNoGC(cx, obj, receiver, id, vp);
     }
     static bool getProperty(JSContext *cx, js::HandleObject obj, js::HandleObject receiver,
                             js::PropertyName *name, js::MutableHandleValue vp)
     {
         JS::RootedId id(cx, js::NameToId(name));
         return getGeneric(cx, obj, receiver, id, vp);
     }
     static bool getPropertyNoGC(JSContext *cx, JSObject *obj, JSObject *receiver,
                                 js::PropertyName *name, js::Value *vp)
     {
         return getGenericNoGC(cx, obj, receiver, js::NameToId(name), vp);
     }
     static inline bool getElement(JSContext *cx, js::HandleObject obj, js::HandleObject receiver,
                                   uint32_t index, js::MutableHandleValue vp);
     static inline bool getElementNoGC(JSContext *cx, JSObject *obj, JSObject *receiver,
                                       uint32_t index, js::Value *vp);
     static bool setGeneric(JSContext *cx, js::HandleObject obj, js::HandleObject receiver,
                            js::HandleId id, js::MutableHandleValue vp, bool strict)
     {
         if (obj->getOps()->setGeneric)
             return nonNativeSetProperty(cx, obj, id, vp, strict);
         return js::baseops::SetPropertyHelper<js::SequentialExecution>(
             cx, obj, receiver, id, js::baseops::Qualified, vp, strict);
     }
     static bool setProperty(JSContext *cx, js::HandleObject obj, js::HandleObject receiver,
                             js::PropertyName *name,
                             js::MutableHandleValue vp, bool strict)
     {
         JS::RootedId id(cx, js::NameToId(name));
         return setGeneric(cx, obj, receiver, id, vp, strict);
     }
     static bool setElement(JSContext *cx, js::HandleObject obj, js::HandleObject receiver,
                            uint32_t index, js::MutableHandleValue vp, bool strict)
     {
         if (obj->getOps()->setElement)
             return nonNativeSetElement(cx, obj, index, vp, strict);
         return js::baseops::SetElementHelper(cx, obj, receiver, index, vp, strict);
     }
     static bool nonNativeSetProperty(JSContext *cx, js::HandleObject obj,
                                      js::HandleId id, js::MutableHandleValue vp, bool strict);
     static bool nonNativeSetElement(JSContext *cx, js::HandleObject obj,
                                     uint32_t index, js::MutableHandleValue vp, bool strict);
     static bool getGenericAttributes(JSContext *cx, js::HandleObject obj,
                                      js::HandleId id, unsigned *attrsp)
     {
         js::GenericAttributesOp op = obj->getOps()->getGenericAttributes;
         return (op ? op : js::baseops::GetAttributes)(cx, obj, id, attrsp);
     }
     static inline bool setGenericAttributes(JSContext *cx, js::HandleObject obj,
                                             js::HandleId id, unsigned *attrsp);
     static inline bool deleteProperty(JSContext *cx, js::HandleObject obj,
                                       js::HandlePropertyName name,
                                       bool *succeeded);
     static inline bool deleteElement(JSContext *cx, js::HandleObject obj,
                                      uint32_t index, bool *succeeded);
     static bool deleteByValue(JSContext *cx, js::HandleObject obj,
                               const js::Value &property, bool *succeeded);
     static inline bool watch(JSContext *cx, JS::HandleObject obj, JS::HandleId id,
                              JS::HandleObject callable);
     static inline bool unwatch(JSContext *cx, JS::HandleObject obj, JS::HandleId id);
     static bool enumerate(JSContext *cx, JS::HandleObject obj, JSIterateOp iterop,
                           JS::MutableHandleValue statep, JS::MutableHandleId idp)
     {
         JSNewEnumerateOp op = obj->getOps()->enumerate;
         return (op ? op : JS_EnumerateState)(cx, obj, iterop, statep, idp);
     }
     static bool defaultValue(JSContext *cx, js::HandleObject obj, JSType hint,
                              js::MutableHandleValue vp)
     {
         JSConvertOp op = obj->getClass()->convert;
         bool ok;
         if (op == JS_ConvertStub)
             ok = js::DefaultValue(cx, obj, hint, vp);
         else
             ok = op(cx, obj, hint, vp);
         JS_ASSERT_IF(ok, vp.isPrimitive());
         return ok;
     }
     static JSObject *thisObject(JSContext *cx, js::HandleObject obj)
     {
         JSObjectOp op = obj->getOps()->thisObject;
         return op ? op(cx, obj) : obj;
     }
     static bool thisObject(JSContext *cx, const js::Value &v, js::Value *vp);
     static bool swap(JSContext *cx, JS::HandleObject a, JS::HandleObject b);
     inline void initArrayClass();
     /*
      * In addition to the generic object interface provided by JSObject,
      * specific types of objects may provide additional operations. To access,
      * these addition operations, callers should use the pattern:
      *
      *   if (obj.is<XObject>()) {
      *     XObject &x = obj.as<XObject>();
      *     x.foo();
      *   }
      *
      * These XObject classes form a hierarchy. For example, for a cloned block
      * object, the following predicates are true: is<ClonedBlockObject>,
      * is<BlockObject>, is<NestedScopeObject> and is<ScopeObject>. Each of
      * these has a respective class that derives and adds operations.
      *
      * A class XObject is defined in a vm/XObject{.h, .cpp, -inl.h} file
      * triplet (along with any class YObject that derives XObject).
      *
      * Note that X represents a low-level representation and does not query the
      * [[Class]] property of object defined by the spec (for this, see
      * js::ObjectClassIs).
      */
     template <class T>
     inline bool is() const { return getClass() == &T::class_; }
     template <class T>
     T &as() {
         JS_ASSERT(is<T>());
         return *static_cast<T *>(this);
     }
     template <class T>
     const T &as() const {
         JS_ASSERT(is<T>());
         return *static_cast<const T *>(this);
     }
     static inline js::ThingRootKind rootKind() { return js::THING_ROOT_OBJECT; }
 #ifdef DEBUG
     void dump();
 #endif
   private:
     static void staticAsserts() {
         static_assert(sizeof(JSObject) == sizeof(js::shadow::Object),
                       "shadow interface must match actual interface");
         static_assert(sizeof(JSObject) == sizeof(js::ObjectImpl),
                       "JSObject itself must not have any fields");
         static_assert(sizeof(JSObject) % sizeof(js::Value) == 0,
                       "fixed slots after an object must be aligned");
         static_assert(js::shadow::Object::MAX_FIXED_SLOTS == MAX_FIXED_SLOTS,
                       "We shouldn't be confused about our actual maximum "
                       "number of fixed slots");
     }
     JSObject() MOZ_DELETE;
     JSObject(const JSObject &other) MOZ_DELETE;
     void operator=(const JSObject &other) MOZ_DELETE;
 };
 template <class U>
 MOZ_ALWAYS_INLINE JS::Handle<U*>
 js::RootedBase<JSObject*>::as() const
 {
     const JS::Rooted<JSObject*> &self = *static_cast<const JS::Rooted<JSObject*>*>(this);
     JS_ASSERT(self->is<U>());
     return Handle<U*>::fromMarkedLocation(reinterpret_cast<U* const*>(self.address()));
 }
 /*
  * The only sensible way to compare JSObject with == is by identity. We use
  * const& instead of * as a syntactic way to assert non-null. This leads to an
  * abundance of address-of operators to identity. Hence this overload.
  */
 static MOZ_ALWAYS_INLINE bool
 operator==(const JSObject &lhs, const JSObject &rhs)
 {
     return &lhs == &rhs;
 }
 static MOZ_ALWAYS_INLINE bool
 operator!=(const JSObject &lhs, const JSObject &rhs)
 {
     return &lhs != &rhs;
 }
 struct JSObject_Slots2 : JSObject { js::Value fslots[2]; };
 struct JSObject_Slots4 : JSObject { js::Value fslots[4]; };
 struct JSObject_Slots8 : JSObject { js::Value fslots[8]; };
 struct JSObject_Slots12 : JSObject { js::Value fslots[12]; };
 struct JSObject_Slots16 : JSObject { js::Value fslots[16]; };
 static inline bool
 js_IsCallable(const js::Value &v)
 {
     return v.isObject() && v.toObject().isCallable();
 }
 inline JSObject *
 GetInnerObject(JSContext *cx, js::HandleObject obj)
 {
     if (JSObjectOp op = obj->getClass()->ext.innerObject)
         return op(cx, obj);
     return obj;
 }
 inline JSObject *
 GetOuterObject(JSContext *cx, js::HandleObject obj)
 {
     if (JSObjectOp op = obj->getClass()->ext.outerObject)
         return op(cx, obj);
     return obj;
 }
 class JSValueArray {
   public:
     const jsval *array;
     size_t length;
     JSValueArray(const jsval *v, size_t c) : array(v), length(c) {}
 };
 class ValueArray {
   public:
     js::Value *array;
     size_t length;
     ValueArray(js::Value *v, size_t c) : array(v), length(c) {}
 };
 namespace js {
 /* Set *resultp to tell whether obj has an own property with the given id. */
 bool
 HasOwnProperty(JSContext *cx, HandleObject obj, HandleId id, bool *resultp);
 template <AllowGC allowGC>
 extern bool
 HasOwnProperty(JSContext *cx, LookupGenericOp lookup,
                typename MaybeRooted<JSObject*, allowGC>::HandleType obj,
                typename MaybeRooted<jsid, allowGC>::HandleType id,
                typename MaybeRooted<JSObject*, allowGC>::MutableHandleType objp,
                typename MaybeRooted<Shape*, allowGC>::MutableHandleType propp);
 typedef JSObject *(*ClassInitializerOp)(JSContext *cx, JS::HandleObject obj);
 /* Fast access to builtin constructors and prototypes. */
 bool
 GetBuiltinConstructor(ExclusiveContext *cx, JSProtoKey key, MutableHandleObject objp);
 bool
 GetBuiltinPrototype(ExclusiveContext *cx, JSProtoKey key, MutableHandleObject objp);
 const Class *
 ProtoKeyToClass(JSProtoKey key);
 JSObject *
 GetBuiltinPrototypePure(GlobalObject *global, JSProtoKey protoKey);
 extern bool
 SetClassAndProto(JSContext *cx, HandleObject obj,
                  const Class *clasp, Handle<TaggedProto> proto, bool *succeeded);
 /*
  * Property-lookup-based access to interface and prototype objects for classes.
  * If the class is built-in (hhas a non-null JSProtoKey), these forward to
  * GetClass{Object,Prototype}.
  */
 bool
 FindClassObject(ExclusiveContext *cx, MutableHandleObject protop, const Class *clasp);
 extern bool
 FindClassPrototype(ExclusiveContext *cx, MutableHandleObject protop, const Class *clasp);
 } /* namespace js */
 /*
  * Select Object.prototype method names shared between jsapi.cpp and jsobj.cpp.
  */
 extern const char js_watch_str[];
 extern const char js_unwatch_str[];
 extern const char js_hasOwnProperty_str[];
 extern const char js_isPrototypeOf_str[];
 extern const char js_propertyIsEnumerable_str[];
 #ifdef JS_OLD_GETTER_SETTER_METHODS
 extern const char js_defineGetter_str[];
 extern const char js_defineSetter_str[];
 extern const char js_lookupGetter_str[];
 extern const char js_lookupSetter_str[];
 #endif
 extern bool
 js_PopulateObject(JSContext *cx, js::HandleObject newborn, js::HandleObject props);
 namespace js {
 extern bool
 DefineOwnProperty(JSContext *cx, JS::HandleObject obj, JS::HandleId id,
                   JS::HandleValue descriptor, bool *bp);
 extern bool
 DefineOwnProperty(JSContext *cx, JS::HandleObject obj, JS::HandleId id,
                   JS::Handle<js::PropertyDescriptor> descriptor, bool *bp);
 /*
  * The NewObjectKind allows an allocation site to specify the type properties
  * and lifetime requirements that must be fixed at allocation time.
  */
 enum NewObjectKind {
     /* This is the default. Most objects are generic. */
     GenericObject,
     /*
      * Singleton objects are treated specially by the type system. This flag
      * ensures that the new object is automatically set up correctly as a
      * singleton and is allocated in the correct heap.
      */
     SingletonObject,
     /*
      * Objects which may be marked as a singleton after allocation must still
      * be allocated on the correct heap, but are not automatically setup as a
      * singleton after allocation.
      */
     MaybeSingletonObject,
     /*
      * Objects which will not benefit from being allocated in the nursery
      * (e.g. because they are known to have a long lifetime) may be allocated
      * with this kind to place them immediately into the tenured generation.
      */
     TenuredObject
 };
 inline gc::InitialHeap
 GetInitialHeap(NewObjectKind newKind, const Class *clasp)
 {
     if (clasp->finalize || newKind != GenericObject)
         return gc::TenuredHeap;
     return gc::DefaultHeap;
 }
 // Specialized call for constructing |this| with a known function callee,
 // and a known prototype.
 extern JSObject *
 CreateThisForFunctionWithProto(JSContext *cx, js::HandleObject callee, JSObject *proto,
                                NewObjectKind newKind = GenericObject);
 // Specialized call for constructing |this| with a known function callee.
 extern JSObject *
 CreateThisForFunction(JSContext *cx, js::HandleObject callee, NewObjectKind newKind);
 // Generic call for constructing |this|.
 extern JSObject *
 CreateThis(JSContext *cx, const js::Class *clasp, js::HandleObject callee);
 extern JSObject *
 CloneObject(JSContext *cx, HandleObject obj, Handle<js::TaggedProto> proto, HandleObject parent);
 extern JSObject *
 DeepCloneObjectLiteral(JSContext *cx, HandleObject obj, NewObjectKind newKind = GenericObject);
 /*
  * Return successfully added or changed shape or nullptr on error.
  */
 extern bool
 DefineNativeProperty(ExclusiveContext *cx, HandleObject obj, HandleId id, HandleValue value,
                      PropertyOp getter, StrictPropertyOp setter, unsigned attrs);
 extern bool
 LookupNativeProperty(ExclusiveContext *cx, HandleObject obj, HandleId id,
                      js::MutableHandleObject objp, js::MutableHandleShape propp);
 /*
  * Call the [[DefineOwnProperty]] internal method of obj.
  *
  * If obj is an array, this follows ES5 15.4.5.1.
  * If obj is any other native object, this follows ES5 8.12.9.
  * If obj is a proxy, this calls the proxy handler's defineProperty method.
  * Otherwise, this reports an error and returns false.
  */
 extern bool
 DefineProperty(JSContext *cx, js::HandleObject obj,
                js::HandleId id, const PropDesc &desc, bool throwError,
                bool *rval);
 bool
 DefineProperties(JSContext *cx, HandleObject obj, HandleObject props);
 /*
  * Read property descriptors from props, as for Object.defineProperties. See
  * ES5 15.2.3.7 steps 3-5.
  */
 extern bool
 ReadPropertyDescriptors(JSContext *cx, HandleObject props, bool checkAccessors,
                         AutoIdVector *ids, AutoPropDescArrayRooter *descs);
 /* Read the name using a dynamic lookup on the scopeChain. */
 extern bool
 LookupName(JSContext *cx, HandlePropertyName name, HandleObject scopeChain,
            MutableHandleObject objp, MutableHandleObject pobjp, MutableHandleShape propp);
 extern bool
 LookupNameNoGC(JSContext *cx, PropertyName *name, JSObject *scopeChain,
                JSObject **objp, JSObject **pobjp, Shape **propp);
 /*
  * Like LookupName except returns the global object if 'name' is not found in
  * any preceding non-global scope.
  *
  * Additionally, pobjp and propp are not needed by callers so they are not
  * returned.
  */
 extern bool
 LookupNameWithGlobalDefault(JSContext *cx, HandlePropertyName name, HandleObject scopeChain,
                             MutableHandleObject objp);
 }
 extern JSObject *
 js_FindVariableScope(JSContext *cx, JSFunction **funp);
 namespace js {
 bool
 NativeGet(JSContext *cx, js::Handle<JSObject*> obj, js::Handle<JSObject*> pobj,
           js::Handle<js::Shape*> shape, js::MutableHandle<js::Value> vp);
 template <js::ExecutionMode mode>
 bool
 NativeSet(typename js::ExecutionModeTraits<mode>::ContextType cx,
           js::Handle<JSObject*> obj, js::Handle<JSObject*> receiver,
           js::Handle<js::Shape*> shape, bool strict, js::MutableHandleValue vp);
 bool
 LookupPropertyPure(JSObject *obj, jsid id, JSObject **objp, Shape **propp);
 bool
 GetPropertyPure(ThreadSafeContext *cx, JSObject *obj, jsid id, Value *vp);
 inline bool
 GetPropertyPure(ThreadSafeContext *cx, JSObject *obj, PropertyName *name, Value *vp)
 {
     return GetPropertyPure(cx, obj, NameToId(name), vp);
 }
 bool
 GetOwnPropertyDescriptor(JSContext *cx, HandleObject obj, HandleId id,
                          MutableHandle<PropertyDescriptor> desc);
 bool
 GetOwnPropertyDescriptor(JSContext *cx, HandleObject obj, HandleId id, MutableHandleValue vp);
 bool
 NewPropertyDescriptorObject(JSContext *cx, Handle<PropertyDescriptor> desc, MutableHandleValue vp);
 /*
  * If obj has an already-resolved data property for id, return true and
  * store the property value in *vp.
  */
 extern bool
 HasDataProperty(JSContext *cx, JSObject *obj, jsid id, Value *vp);
 inline bool
 HasDataProperty(JSContext *cx, JSObject *obj, PropertyName *name, Value *vp)
 {
     return HasDataProperty(cx, obj, NameToId(name), vp);
 }
 extern bool
 IsDelegate(JSContext *cx, HandleObject obj, const Value &v, bool *result);
 // obj is a JSObject*, but we root it immediately up front. We do it
 // that way because we need a Rooted temporary in this method anyway.
 extern bool
 IsDelegateOfObject(JSContext *cx, HandleObject protoObj, JSObject* obj, bool *result);
 bool
 GetObjectElementOperationPure(ThreadSafeContext *cx, JSObject *obj, const Value &prop, Value *vp);
 /* Wrap boolean, number or string as Boolean, Number or String object. */
 extern JSObject *
 PrimitiveToObject(JSContext *cx, const Value &v);
 } /* namespace js */
 namespace js {
 /*
  * 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.
  */
 extern JSObject *
 ToObjectSlow(JSContext *cx, HandleValue vp, bool reportScanStack);
 /* For object conversion in e.g. native functions. */
 MOZ_ALWAYS_INLINE JSObject *
 ToObject(JSContext *cx, HandleValue vp)
 {
     if (vp.isObject())
         return &vp.toObject();
     return ToObjectSlow(cx, vp, false);
 }
 /* For converting stack values to objects. */
 MOZ_ALWAYS_INLINE JSObject *
 ToObjectFromStack(JSContext *cx, HandleValue vp)
 {
     if (vp.isObject())
         return &vp.toObject();
     return ToObjectSlow(cx, vp, true);
 }
 template<XDRMode mode>
 bool
 XDRObjectLiteral(XDRState<mode> *xdr, MutableHandleObject obj);
 extern JSObject *
 CloneObjectLiteral(JSContext *cx, HandleObject parent, HandleObject srcObj);
 } /* namespace js */
 extern void
 js_GetObjectSlotName(JSTracer *trc, char *buf, size_t bufsize);
 extern bool
 js_ReportGetterOnlyAssignment(JSContext *cx, bool strict);
 namespace js {
 extern JSObject *
 NonNullObject(JSContext *cx, const Value &v);
 extern const char *
 InformalValueTypeName(const Value &v);
 extern bool
 GetFirstArgumentAsObject(JSContext *cx, const CallArgs &args, const char *method,
                          MutableHandleObject objp);
 /* Helpers for throwing. These always return false. */
 extern bool
 Throw(JSContext *cx, jsid id, unsigned errorNumber);
 extern bool
 Throw(JSContext *cx, JSObject *obj, unsigned errorNumber);
 }  /* namespace js */
 #endif /* jsobj_h */

The Tor Browser / annotate

js/src/jsobj.h@b8a032363ba2 (annotated)

js/src/jsobj.h