/* static */ void
ArgumentsObject::MaybeForwardToCallObject(AbstractFramePtr frame, ArgumentsObject* obj,
ArgumentsData* data)
{
JSScript* script = frame.script();
if (frame.fun()->needsCallObject() && script->argsObjAliasesFormals()) {
obj->initFixedSlot(MAYBE_CALL_SLOT, ObjectValue(frame.callObj()));
for (AliasedFormalIter fi(script); fi; fi++)
data->args[fi.frameIndex()] = MagicScopeSlotValue(fi.scopeSlot());
}
}
/* static */ void
ArgumentsObject::MaybeForwardToCallObject(jit::JitFrameLayout* frame, HandleObject callObj,
ArgumentsObject* obj, ArgumentsData* data)
{
JSFunction* callee = jit::CalleeTokenToFunction(frame->calleeToken());
JSScript* script = callee->nonLazyScript();
if (callee->needsCallObject() && script->argsObjAliasesFormals()) {
MOZ_ASSERT(callObj && callObj->is<CallObject>());
obj->initFixedSlot(MAYBE_CALL_SLOT, ObjectValue(*callObj.get()));
for (AliasedFormalIter fi(script); fi; fi++)
data->args[fi.frameIndex()] = MagicScopeSlotValue(fi.scopeSlot());
}
}
/* static */ void
ArgumentsObject::MaybeForwardToCallObject(ion::IonJSFrameLayout *frame, HandleObject callObj,
JSObject *obj, ArgumentsData *data)
{
JSFunction *callee = ion::CalleeTokenToFunction(frame->calleeToken());
JSScript *script = callee->nonLazyScript();
if (callee->isHeavyweight() && script->argsObjAliasesFormals()) {
JS_ASSERT(callObj && callObj->isCall());
obj->initFixedSlot(MAYBE_CALL_SLOT, ObjectValue(*callObj.get()));
for (AliasedFormalIter fi(script); fi; fi++)
data->args[fi.frameIndex()] = MagicValue(JS_FORWARD_TO_CALL_OBJECT);
}
}
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;
}
