/* 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; }