void
Shape::removeChild(UnrootedShape child)
{
    JS_ASSERT(!child->inDictionary());
    JS_ASSERT(child->parent == this);

    KidsPointer *kidp = &kids;

    if (kidp->isShape()) {
        JS_ASSERT(kidp->toShape() == child);
        kidp->setNull();
        child->parent = NULL;
        return;
    }

    KidsHash *hash = kidp->toHash();
    JS_ASSERT(hash->count() >= 2);      /* otherwise kidp->isShape() should be true */

    hash->remove(child);
    child->parent = NULL;

    if (hash->count() == 1) {
        /* Convert from HASH form back to SHAPE form. */
        KidsHash::Range r = hash->all();
        Shape *otherChild = r.front();
        JS_ASSERT((r.popFront(), r.empty()));    /* No more elements! */
        kidp->setShape(otherChild);
        js_delete(hash);
    }
}
bool
PropertyTree::insertChild(JSContext *cx, UnrootedShape parent, UnrootedShape child)
{
    JS_ASSERT(!parent->inDictionary());
    JS_ASSERT(!child->parent);
    JS_ASSERT(!child->inDictionary());
    JS_ASSERT(cx->compartment == compartment);
    JS_ASSERT(child->compartment() == parent->compartment());

    KidsPointer *kidp = &parent->kids;

    if (kidp->isNull()) {
        child->setParent(parent);
        kidp->setShape(child);
        return true;
    }

    if (kidp->isShape()) {
        UnrootedShape shape = kidp->toShape();
        JS_ASSERT(shape != child);
        JS_ASSERT(!shape->matches(child));

        KidsHash *hash = HashChildren(shape, child);
        if (!hash) {
            JS_ReportOutOfMemory(cx);
            return false;
        }
        kidp->setHash(hash);
        child->setParent(parent);
        return true;
    }

    if (!kidp->toHash()->putNew(child, child)) {
        JS_ReportOutOfMemory(cx);
        return false;
    }

    child->setParent(parent);
    return true;
}
static void
StatsCellCallback(JSRuntime *rt, void *data, void *thing, JSGCTraceKind traceKind,
                  size_t thingSize)
{
    IteratorClosure *closure = static_cast<IteratorClosure *>(data);
    RuntimeStats *rtStats = closure->rtStats;
    CompartmentStats *cStats = rtStats->currCompartmentStats;
    switch (traceKind) {
    case JSTRACE_OBJECT:
    {
        JSObject *obj = static_cast<JSObject *>(thing);
        if (obj->isFunction()) {
            cStats->gcHeapObjectsFunction += thingSize;
        } else if (obj->isArray()) {
            cStats->gcHeapObjectsDenseArray += thingSize;
        } else if (obj->isCrossCompartmentWrapper()) {
            cStats->gcHeapObjectsCrossCompartmentWrapper += thingSize;
        } else {
            cStats->gcHeapObjectsOrdinary += thingSize;
        }

        ObjectsExtraSizes objectsExtra;
        obj->sizeOfExcludingThis(rtStats->mallocSizeOf, &objectsExtra);
        cStats->objectsExtra.add(objectsExtra);

        // JSObject::sizeOfExcludingThis() doesn't measure objectsExtraPrivate,
        // so we do it here.
        if (ObjectPrivateVisitor *opv = closure->opv) {
            nsISupports *iface;
            if (opv->getISupports(obj, &iface) && iface) {
                cStats->objectsExtra.private_ += opv->sizeOfIncludingThis(iface);
            }
        }
        break;
    }
    case JSTRACE_STRING:
    {
        JSString *str = static_cast<JSString *>(thing);

        size_t strSize = str->sizeOfExcludingThis(rtStats->mallocSizeOf);

        // If we can't grow hugeStrings, let's just call this string non-huge.
        // We're probably about to OOM anyway.
        if (strSize >= HugeStringInfo::MinSize() && cStats->hugeStrings.growBy(1)) {
            cStats->gcHeapStringsNormal += thingSize;
            HugeStringInfo &info = cStats->hugeStrings.back();
            info.length = str->length();
            info.size = strSize;
            PutEscapedString(info.buffer, sizeof(info.buffer), &str->asLinear(), 0);
        } else if (str->isShort()) {
            MOZ_ASSERT(strSize == 0);
            cStats->gcHeapStringsShort += thingSize;
        } else {
            cStats->gcHeapStringsNormal += thingSize;
            cStats->stringCharsNonHuge += strSize;
        }
        break;
    }
    case JSTRACE_SHAPE:
    {
        UnrootedShape shape = static_cast<RawShape>(thing);
        size_t propTableSize, kidsSize;
        shape->sizeOfExcludingThis(rtStats->mallocSizeOf, &propTableSize, &kidsSize);
        if (shape->inDictionary()) {
            cStats->gcHeapShapesDict += thingSize;
            cStats->shapesExtraDictTables += propTableSize;
            JS_ASSERT(kidsSize == 0);
        } else {
            if (shape->base()->getObjectParent() == shape->compartment()->maybeGlobal()) {
                cStats->gcHeapShapesTreeGlobalParented += thingSize;
            } else {
                cStats->gcHeapShapesTreeNonGlobalParented += thingSize;
            }
            cStats->shapesExtraTreeTables += propTableSize;
            cStats->shapesExtraTreeShapeKids += kidsSize;
        }
        break;
    }
    case JSTRACE_BASE_SHAPE:
    {
        cStats->gcHeapShapesBase += thingSize;
        break;
    }
    case JSTRACE_SCRIPT:
    {
        JSScript *script = static_cast<JSScript *>(thing);
        cStats->gcHeapScripts += thingSize;
        cStats->scriptData += script->sizeOfData(rtStats->mallocSizeOf);
#ifdef JS_METHODJIT
        cStats->jaegerData += script->sizeOfJitScripts(rtStats->mallocSizeOf);
# ifdef JS_ION
        cStats->ionData += ion::MemoryUsed(script, rtStats->mallocSizeOf);
# endif
#endif

        ScriptSource *ss = script->scriptSource();
        SourceSet::AddPtr entry = closure->seenSources.lookupForAdd(ss);
        if (!entry) {
            closure->seenSources.add(entry, ss); // Not much to be done on failure.
            rtStats->runtime.scriptSources += ss->sizeOfIncludingThis(rtStats->mallocSizeOf);
        }
        break;
    }
    case JSTRACE_IONCODE:
    {
#ifdef JS_METHODJIT
# ifdef JS_ION
        cStats->gcHeapIonCodes += thingSize;
        // The code for a script is counted in ExecutableAllocator::sizeOfCode().
# endif
#endif
        break;
    }
    case JSTRACE_TYPE_OBJECT:
    {
        types::TypeObject *obj = static_cast<types::TypeObject *>(thing);
        cStats->gcHeapTypeObjects += thingSize;
        cStats->typeInference.typeObjects += obj->sizeOfExcludingThis(rtStats->mallocSizeOf);
        break;
    }
    }
    // Yes, this is a subtraction:  see StatsArenaCallback() for details.
    cStats->gcHeapUnusedGcThings -= thingSize;
}