| // Copyright 2017 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" |
| #include "src/builtins/growable-fixed-array-gen.h" |
| |
| #include "src/heap/factory-inl.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| using compiler::Node; |
| |
| TNode<Object> IteratorBuiltinsAssembler::GetIteratorMethod(Node* context, |
| Node* object) { |
| return GetProperty(context, object, factory()->iterator_symbol()); |
| } |
| |
| IteratorRecord IteratorBuiltinsAssembler::GetIterator(Node* context, |
| Node* object, |
| Label* if_exception, |
| Variable* exception) { |
| Node* method = GetIteratorMethod(context, object); |
| return GetIterator(context, object, method, if_exception, exception); |
| } |
| |
| IteratorRecord IteratorBuiltinsAssembler::GetIterator(Node* context, |
| Node* object, |
| Node* method, |
| Label* if_exception, |
| Variable* exception) { |
| GotoIfException(method, if_exception, exception); |
| |
| Label if_not_callable(this, Label::kDeferred), if_callable(this); |
| GotoIf(TaggedIsSmi(method), &if_not_callable); |
| Branch(IsCallable(method), &if_callable, &if_not_callable); |
| |
| BIND(&if_not_callable); |
| { |
| Node* ret = CallRuntime(Runtime::kThrowTypeError, context, |
| SmiConstant(MessageTemplate::kNotIterable), object); |
| GotoIfException(ret, if_exception, exception); |
| Unreachable(); |
| } |
| |
| BIND(&if_callable); |
| { |
| Callable callable = CodeFactory::Call(isolate()); |
| Node* iterator = CallJS(callable, context, method, object); |
| GotoIfException(iterator, if_exception, exception); |
| |
| Label get_next(this), if_notobject(this, Label::kDeferred); |
| GotoIf(TaggedIsSmi(iterator), &if_notobject); |
| Branch(IsJSReceiver(iterator), &get_next, &if_notobject); |
| |
| BIND(&if_notobject); |
| { |
| Node* ret = CallRuntime(Runtime::kThrowSymbolIteratorInvalid, context); |
| GotoIfException(ret, if_exception, exception); |
| Unreachable(); |
| } |
| |
| BIND(&get_next); |
| Node* const next = GetProperty(context, iterator, factory()->next_string()); |
| GotoIfException(next, if_exception, exception); |
| |
| return IteratorRecord{TNode<JSReceiver>::UncheckedCast(iterator), |
| TNode<Object>::UncheckedCast(next)}; |
| } |
| } |
| |
| Node* IteratorBuiltinsAssembler::IteratorStep( |
| Node* context, const IteratorRecord& iterator, Label* if_done, |
| Node* fast_iterator_result_map, Label* if_exception, Variable* exception) { |
| DCHECK_NOT_NULL(if_done); |
| // 1. a. Let result be ? Invoke(iterator, "next", « »). |
| Callable callable = CodeFactory::Call(isolate()); |
| Node* result = CallJS(callable, context, iterator.next, iterator.object); |
| GotoIfException(result, if_exception, exception); |
| |
| // 3. If Type(result) is not Object, throw a TypeError exception. |
| Label if_notobject(this, Label::kDeferred), return_result(this); |
| GotoIf(TaggedIsSmi(result), &if_notobject); |
| Node* result_map = LoadMap(result); |
| |
| if (fast_iterator_result_map != nullptr) { |
| // Fast iterator result case: |
| Label if_generic(this); |
| |
| // 4. Return result. |
| GotoIfNot(WordEqual(result_map, fast_iterator_result_map), &if_generic); |
| |
| // IteratorComplete |
| // 2. Return ToBoolean(? Get(iterResult, "done")). |
| Node* done = LoadObjectField(result, JSIteratorResult::kDoneOffset); |
| BranchIfToBooleanIsTrue(done, if_done, &return_result); |
| |
| BIND(&if_generic); |
| } |
| |
| // Generic iterator result case: |
| { |
| // 3. If Type(result) is not Object, throw a TypeError exception. |
| GotoIfNot(IsJSReceiverMap(result_map), &if_notobject); |
| |
| // IteratorComplete |
| // 2. Return ToBoolean(? Get(iterResult, "done")). |
| Node* done = GetProperty(context, result, factory()->done_string()); |
| GotoIfException(done, if_exception, exception); |
| BranchIfToBooleanIsTrue(done, if_done, &return_result); |
| } |
| |
| BIND(&if_notobject); |
| { |
| Node* ret = |
| CallRuntime(Runtime::kThrowIteratorResultNotAnObject, context, result); |
| GotoIfException(ret, if_exception, exception); |
| Unreachable(); |
| } |
| |
| BIND(&return_result); |
| return result; |
| } |
| |
| Node* IteratorBuiltinsAssembler::IteratorValue(Node* context, Node* result, |
| Node* fast_iterator_result_map, |
| Label* if_exception, |
| Variable* exception) { |
| CSA_ASSERT(this, IsJSReceiver(result)); |
| |
| Label exit(this); |
| VARIABLE(var_value, MachineRepresentation::kTagged); |
| if (fast_iterator_result_map != nullptr) { |
| // Fast iterator result case: |
| Label if_generic(this); |
| Node* map = LoadMap(result); |
| GotoIfNot(WordEqual(map, fast_iterator_result_map), &if_generic); |
| var_value.Bind(LoadObjectField(result, JSIteratorResult::kValueOffset)); |
| Goto(&exit); |
| |
| BIND(&if_generic); |
| } |
| |
| // Generic iterator result case: |
| { |
| Node* value = GetProperty(context, result, factory()->value_string()); |
| GotoIfException(value, if_exception, exception); |
| var_value.Bind(value); |
| Goto(&exit); |
| } |
| |
| BIND(&exit); |
| return var_value.value(); |
| } |
| |
| void IteratorBuiltinsAssembler::IteratorCloseOnException( |
| Node* context, const IteratorRecord& iterator, Label* if_exception, |
| Variable* exception) { |
| // Perform ES #sec-iteratorclose when an exception occurs. This simpler |
| // algorithm does not include redundant steps which are never reachable from |
| // the spec IteratorClose algorithm. |
| DCHECK_NOT_NULL(if_exception); |
| DCHECK_NOT_NULL(exception); |
| CSA_ASSERT(this, IsNotTheHole(exception->value())); |
| CSA_ASSERT(this, IsJSReceiver(iterator.object)); |
| |
| // Let return be ? GetMethod(iterator, "return"). |
| Node* method = |
| GetProperty(context, iterator.object, factory()->return_string()); |
| GotoIfException(method, if_exception, exception); |
| |
| // If return is undefined, return Completion(completion). |
| GotoIf(Word32Or(IsUndefined(method), IsNull(method)), if_exception); |
| |
| { |
| // Let innerResult be Call(return, iterator, « »). |
| // If an exception occurs, the original exception remains bound |
| Node* inner_result = |
| CallJS(CodeFactory::Call(isolate()), context, method, iterator.object); |
| GotoIfException(inner_result, if_exception, nullptr); |
| |
| // (If completion.[[Type]] is throw) return Completion(completion). |
| Goto(if_exception); |
| } |
| } |
| |
| void IteratorBuiltinsAssembler::IteratorCloseOnException( |
| Node* context, const IteratorRecord& iterator, Variable* exception) { |
| Label rethrow(this, Label::kDeferred); |
| IteratorCloseOnException(context, iterator, &rethrow, exception); |
| |
| BIND(&rethrow); |
| CallRuntime(Runtime::kReThrow, context, exception->value()); |
| Unreachable(); |
| } |
| |
| TNode<JSArray> IteratorBuiltinsAssembler::IterableToList( |
| TNode<Context> context, TNode<Object> iterable, TNode<Object> iterator_fn) { |
| Label fast_path(this), slow_path(this), done(this); |
| |
| TVARIABLE(JSArray, created_list); |
| |
| Branch(IsFastJSArrayWithNoCustomIteration(iterable, context), &fast_path, |
| &slow_path); |
| |
| // This is a fast-path for ignoring the iterator. |
| BIND(&fast_path); |
| { |
| TNode<JSArray> input_array = CAST(iterable); |
| created_list = CAST(CloneFastJSArray(context, input_array)); |
| Goto(&done); |
| } |
| |
| BIND(&slow_path); |
| { |
| // 1. Let iteratorRecord be ? GetIterator(items, method). |
| IteratorRecord iterator_record = |
| GetIterator(context, iterable, iterator_fn); |
| |
| // 2. Let values be a new empty List. |
| GrowableFixedArray values(state()); |
| |
| Variable* vars[] = {values.var_array(), values.var_length(), |
| values.var_capacity()}; |
| Label loop_start(this, 3, vars), loop_end(this); |
| Goto(&loop_start); |
| // 3. Let next be true. |
| // 4. Repeat, while next is not false |
| BIND(&loop_start); |
| { |
| // a. Set next to ? IteratorStep(iteratorRecord). |
| TNode<Object> next = |
| CAST(IteratorStep(context, iterator_record, &loop_end)); |
| // b. If next is not false, then |
| // i. Let nextValue be ? IteratorValue(next). |
| TNode<Object> next_value = CAST(IteratorValue(context, next)); |
| // ii. Append nextValue to the end of the List values. |
| values.Push(next_value); |
| Goto(&loop_start); |
| } |
| BIND(&loop_end); |
| |
| created_list = values.ToJSArray(context); |
| Goto(&done); |
| } |
| |
| BIND(&done); |
| return created_list.value(); |
| } |
| |
| TNode<JSArray> IteratorBuiltinsAssembler::IterableToList( |
| TNode<Context> context, TNode<Object> iterable) { |
| TNode<Object> method = GetIteratorMethod(context, iterable); |
| return IterableToList(context, iterable, method); |
| } |
| |
| } // namespace internal |
| } // namespace v8 |