// Copyright 2018 the V8 project authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #include 'src/builtins/builtins-iterator-gen.h' namespace iterator { // Returned from IteratorBuiltinsAssembler::GetIterator(). @export struct IteratorRecord { // iteratorRecord.[[Iterator]] object: JSReceiver; // iteratorRecord.[[NextMethod]] next: JSAny; } extern macro IteratorBuiltinsAssembler::FastIterableToList( implicit context: Context)(JSAny): JSArray labels Slow; extern macro IteratorBuiltinsAssembler::GetIteratorMethod( implicit context: Context)(JSAny): JSAny; extern macro IteratorBuiltinsAssembler::GetIterator(implicit context: Context)( JSAny): IteratorRecord; extern macro IteratorBuiltinsAssembler::GetIterator(implicit context: Context)( JSAny, JSAny): IteratorRecord; extern macro IteratorBuiltinsAssembler::IteratorStep(implicit context: Context)( IteratorRecord): JSReceiver labels Done; extern macro IteratorBuiltinsAssembler::IteratorStep(implicit context: Context)( IteratorRecord, Map): JSReceiver labels Done; extern macro IteratorBuiltinsAssembler::IteratorValue( implicit context: Context)(JSReceiver): JSAny; extern macro IteratorBuiltinsAssembler::IteratorValue( implicit context: Context)(JSReceiver, Map): JSAny; extern macro IteratorBuiltinsAssembler::IterableToList( implicit context: Context)(JSAny, JSAny): JSArray; extern macro IteratorBuiltinsAssembler::StringListFromIterable( implicit context: Context)(JSAny): JSArray; extern builtin IterableToListWithSymbolLookup(implicit context: Context)(JSAny): JSArray; extern builtin IterableToFixedArrayWithSymbolLookupSlow( implicit context: Context)(JSAny): FixedArray; transitioning builtin GetIteratorWithFeedback( context: Context, receiver: JSAny, loadSlot: TaggedIndex, callSlot: TaggedIndex, maybeFeedbackVector: Undefined|FeedbackVector): JSAny { // TODO(v8:9891): Remove this assert once all callers are ported to Torque. // This assert ensures correctness of maybeFeedbackVector's type which can // be easily broken for calls from CSA. assert( IsUndefined(maybeFeedbackVector) || Is<FeedbackVector>(maybeFeedbackVector)); let iteratorMethod: JSAny; typeswitch (maybeFeedbackVector) { case (Undefined): { iteratorMethod = GetProperty(receiver, IteratorSymbolConstant()); } case (feedback: FeedbackVector): { iteratorMethod = LoadIC( context, receiver, IteratorSymbolConstant(), loadSlot, feedback); } } // TODO(v8:10047): Use TaggedIndex here once TurboFan supports it. const callSlotSmi: Smi = TaggedIndexToSmi(callSlot); return CallIteratorWithFeedback( context, receiver, iteratorMethod, callSlotSmi, maybeFeedbackVector); } extern macro LoadContextFromBaseline(): Context; extern macro LoadFeedbackVectorFromBaseline(): FeedbackVector; transitioning builtin GetIteratorBaseline( receiver: JSAny, loadSlot: TaggedIndex, callSlot: TaggedIndex): JSAny { const context: Context = LoadContextFromBaseline(); const feedback: FeedbackVector = LoadFeedbackVectorFromBaseline(); const iteratorMethod: JSAny = LoadIC(context, receiver, IteratorSymbolConstant(), loadSlot, feedback); // TODO(v8:10047): Use TaggedIndex here once TurboFan supports it. const callSlotSmi: Smi = TaggedIndexToSmi(callSlot); return CallIteratorWithFeedback( context, receiver, iteratorMethod, callSlotSmi, feedback); } extern macro CreateAsyncFromSyncIterator(Context, JSAny): JSAny; transitioning builtin CreateAsyncFromSyncIteratorBaseline(syncIterator: JSAny): JSAny { const context: Context = LoadContextFromBaseline(); return CreateAsyncFromSyncIterator(context, syncIterator); } macro GetLazyReceiver(receiver: JSAny): JSAny { return receiver; } transitioning builtin CallIteratorWithFeedback( context: Context, receiver: JSAny, iteratorMethod: JSAny, callSlot: Smi, feedback: Undefined|FeedbackVector): JSAny { // TODO(v8:10047): Use TaggedIndex here once TurboFan supports it. const callSlotUnTagged: uintptr = Unsigned(SmiUntag(callSlot)); ic::CollectCallFeedback( iteratorMethod, %MakeLazy<JSAny, JSAny>('GetLazyReceiver', receiver), context, feedback, callSlotUnTagged); const iteratorCallable: Callable = Cast<Callable>(iteratorMethod) otherwise ThrowIteratorError(receiver); return Call(context, iteratorCallable, receiver); } // https://tc39.es/ecma262/#sec-iteratorclose @export transitioning macro IteratorCloseOnException(implicit context: Context)( iterator: IteratorRecord) { try { // 4. Let innerResult be GetMethod(iterator, "return"). const method = GetProperty(iterator.object, kReturnString); // 5. If innerResult.[[Type]] is normal, then // a. Let return be innerResult.[[Value]]. // b. If return is undefined, return Completion(completion). if (method == Undefined || method == Null) return; // c. Set innerResult to Call(return, iterator). // If an exception occurs, the original exception remains bound Call(context, method, iterator.object); } catch (_e) { // Swallow the exception. } // (If completion.[[Type]] is throw) return Completion(completion). } }