Exemplo n.º 1
0
/* static */ ArgumentsObject *
ArgumentsObject::create(JSContext *cx, HandleScript script, HandleFunction callee, unsigned numActuals,
                        CopyArgs &copy)
{
    RootedObject proto(cx, callee->global().getOrCreateObjectPrototype(cx));
    if (!proto)
        return NULL;

    bool strict = callee->strict();
    Class *clasp = strict ? &StrictArgumentsObjectClass : &NormalArgumentsObjectClass;

    RootedTypeObject type(cx, proto->getNewType(cx, clasp));
    if (!type)
        return NULL;

    RootedShape shape(cx, EmptyShape::getInitialShape(cx, clasp, TaggedProto(proto),
                                                      proto->getParent(), FINALIZE_KIND,
                                                      BaseShape::INDEXED));
    if (!shape)
        return NULL;

    unsigned numFormals = callee->nargs;
    unsigned numDeletedWords = NumWordsForBitArrayOfLength(numActuals);
    unsigned numArgs = Max(numActuals, numFormals);
    unsigned numBytes = offsetof(ArgumentsData, args) +
                        numDeletedWords * sizeof(size_t) +
                        numArgs * sizeof(Value);

    ArgumentsData *data = (ArgumentsData *)cx->malloc_(numBytes);
    if (!data)
        return NULL;

    data->numArgs = numArgs;
    data->callee.init(ObjectValue(*callee.get()));
    data->script = script;

    /* Copy [0, numArgs) into data->slots. */
    HeapValue *dst = data->args, *dstEnd = data->args + numArgs;
    copy.copyArgs(cx, dst, numArgs);

    data->deletedBits = reinterpret_cast<size_t *>(dstEnd);
    ClearAllBitArrayElements(data->deletedBits, numDeletedWords);

    JSObject *obj = JSObject::create(cx, FINALIZE_KIND, GetInitialHeap(GenericObject, clasp),
                                     shape, type);
    if (!obj) {
        js_free(data);
        return NULL;
    }

    obj->initFixedSlot(INITIAL_LENGTH_SLOT, Int32Value(numActuals << PACKED_BITS_COUNT));
    obj->initFixedSlot(DATA_SLOT, PrivateValue(data));

    copy.maybeForwardToCallObject(obj, data);

    ArgumentsObject &argsobj = obj->asArguments();
    JS_ASSERT(argsobj.initialLength() == numActuals);
    JS_ASSERT(!argsobj.hasOverriddenLength());
    return &argsobj;
}
Exemplo n.º 2
0
ArgumentsObject *
ArgumentsObject::create(JSContext *cx, uint32_t argc, HandleObject callee)
{
    JS_ASSERT(argc <= StackSpace::ARGS_LENGTH_MAX);

    RootedVarObject proto(cx, callee->global().getOrCreateObjectPrototype(cx));
    if (!proto)
        return NULL;

    RootedVarTypeObject type(cx);

    type = proto->getNewType(cx);
    if (!type)
        return NULL;

    bool strict = callee->toFunction()->inStrictMode();
    Class *clasp = strict ? &StrictArgumentsObjectClass : &NormalArgumentsObjectClass;

    RootedVarShape emptyArgumentsShape(cx);
    emptyArgumentsShape =
        EmptyShape::getInitialShape(cx, clasp, proto,
                                    proto->getParent(), FINALIZE_KIND,
                                    BaseShape::INDEXED);
    if (!emptyArgumentsShape)
        return NULL;

    unsigned numDeletedWords = NumWordsForBitArrayOfLength(argc);
    unsigned numBytes = offsetof(ArgumentsData, slots) +
                        numDeletedWords * sizeof(size_t) +
                        argc * sizeof(Value);

    ArgumentsData *data = (ArgumentsData *)cx->malloc_(numBytes);
    if (!data)
        return NULL;

    data->callee.init(ObjectValue(*callee));
    for (HeapValue *vp = data->slots; vp != data->slots + argc; vp++)
        vp->init(UndefinedValue());
    data->deletedBits = (size_t *)(data->slots + argc);
    ClearAllBitArrayElements(data->deletedBits, numDeletedWords);

    /* We have everything needed to fill in the object, so make the object. */
    JSObject *obj = JSObject::create(cx, FINALIZE_KIND, emptyArgumentsShape, type, NULL);
    if (!obj)
        return NULL;

    ArgumentsObject &argsobj = obj->asArguments();

    JS_ASSERT(UINT32_MAX > (uint64_t(argc) << PACKED_BITS_COUNT));
    argsobj.initInitialLength(argc);
    argsobj.initData(data);
    argsobj.setStackFrame(NULL);

    JS_ASSERT(argsobj.numFixedSlots() >= NormalArgumentsObject::RESERVED_SLOTS);
    JS_ASSERT(argsobj.numFixedSlots() >= StrictArgumentsObject::RESERVED_SLOTS);

    return &argsobj;
}
Exemplo n.º 3
0
ArgumentsObject *
ArgumentsObject::create(JSContext *cx, StackFrame *fp)
{
    JSFunction &callee = fp->callee();
    RootedObject proto(cx, callee.global().getOrCreateObjectPrototype(cx));
    if (!proto)
        return NULL;

    RootedTypeObject type(cx);
    type = proto->getNewType(cx);
    if (!type)
        return NULL;

    bool strict = callee.inStrictMode();
    Class *clasp = strict ? &StrictArgumentsObjectClass : &NormalArgumentsObjectClass;

    RootedShape emptyArgumentsShape(cx);
    emptyArgumentsShape =
        EmptyShape::getInitialShape(cx, clasp, proto,
                                    proto->getParent(), FINALIZE_KIND,
                                    BaseShape::INDEXED);
    if (!emptyArgumentsShape)
        return NULL;

    unsigned numActuals = fp->numActualArgs();
    unsigned numFormals = fp->numFormalArgs();
    unsigned numDeletedWords = NumWordsForBitArrayOfLength(numActuals);
    unsigned numArgs = Max(numActuals, numFormals);
    unsigned numBytes = offsetof(ArgumentsData, args) +
                        numDeletedWords * sizeof(size_t) +
                        numArgs * sizeof(Value);

    ArgumentsData *data = (ArgumentsData *)cx->malloc_(numBytes);
    if (!data)
        return NULL;

    data->numArgs = numArgs;
    data->callee.init(ObjectValue(callee));
    data->script = fp->script();

    /* Copy [0, numArgs) into data->slots. */
    HeapValue *dst = data->args, *dstEnd = data->args + numArgs;
    for (Value *src = fp->formals(), *end = src + numFormals; src != end; ++src, ++dst)
        dst->init(*src);
    if (numActuals > numFormals) {
        for (Value *src = fp->actuals() + numFormals; dst != dstEnd; ++src, ++dst)
            dst->init(*src);
    } else if (numActuals < numFormals) {
        for (; dst != dstEnd; ++dst)
            dst->init(UndefinedValue());
    }

    data->deletedBits = reinterpret_cast<size_t *>(dstEnd);
    ClearAllBitArrayElements(data->deletedBits, numDeletedWords);

    JSObject *obj = JSObject::create(cx, FINALIZE_KIND, emptyArgumentsShape, type, NULL);
    if (!obj)
        return NULL;

    obj->initFixedSlot(INITIAL_LENGTH_SLOT, Int32Value(numActuals << PACKED_BITS_COUNT));
    obj->initFixedSlot(DATA_SLOT, PrivateValue(data));

    /*
     * If it exists and the arguments object aliases formals, the call object
     * is the canonical location for formals.
     */
    JSScript *script = fp->script();
    if (fp->fun()->isHeavyweight() && script->argsObjAliasesFormals()) {
        obj->initFixedSlot(MAYBE_CALL_SLOT, ObjectValue(fp->callObj()));

        /* Flag each slot that canonically lives in the callObj. */
        if (script->bindingsAccessedDynamically) {
            for (unsigned i = 0; i < numFormals; ++i)
                data->args[i] = MagicValue(JS_FORWARD_TO_CALL_OBJECT);
        } else {
            for (unsigned i = 0; i < script->numClosedArgs(); ++i)
                data->args[script->getClosedArg(i)] = MagicValue(JS_FORWARD_TO_CALL_OBJECT);
        }
    }

    ArgumentsObject &argsobj = obj->asArguments();
    JS_ASSERT(argsobj.initialLength() == numActuals);
    JS_ASSERT(!argsobj.hasOverriddenLength());
    return &argsobj;
}