[stubs] Add CreateIterResultObject stub

src/builtins/builtins-object.cc

 // Copyright 2016 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-utils.h"
 #include "src/builtins/builtins.h"
 #include "src/code-factory.h"
 #include "src/code-stub-assembler.h"
 #include "src/property-descriptor.h"
 
@@ skipping 909 matching lines @@
   HandleScope scope(isolate);
   Handle<Object> object = args.atOrUndefined(isolate, 1);
   if (object->IsJSReceiver()) {
     MAYBE_RETURN(JSReceiver::SetIntegrityLevel(Handle<JSReceiver>::cast(object),
                                                SEALED, Object::THROW_ON_ERROR),
                  isolate->heap()->exception());
   }
   return *object;
 }
 
+void Builtins::Generate_CreateIterResultObject(
+    compiler::CodeAssemblerState* state) {
+  typedef CreateIterResultObjectDescriptor Descriptor;
+  typedef compiler::Node Node;
+  CodeStubAssembler a(state);
+
+  Node* const value = a.Parameter(Descriptor::kValue);
+  Node* const done = a.Parameter(Descriptor::kDone);
+  Node* const context = a.Parameter(Descriptor::kContext);
+
+  Node* const native_context = a.LoadNativeContext(context);
+  Node* const map =
+      a.LoadContextElement(native_context, Context::ITERATOR_RESULT_MAP_INDEX);
+
+  Node* const result = a.AllocateJSObjectFromMap(map);
+
+  a.StoreObjectFieldNoWriteBarrier(result, JSIteratorResult::kValueOffset,
+                                   value);
+  a.StoreObjectFieldNoWriteBarrier(result, JSIteratorResult::kDoneOffset, done);
+
+  a.Return(result);
+}
+
 void Builtins::Generate_HasProperty(compiler::CodeAssemblerState* state) {
   typedef HasPropertyDescriptor Descriptor;
   typedef compiler::Node Node;
   CodeStubAssembler assembler(state);
 
   Node* key = assembler.Parameter(Descriptor::kKey);
   Node* object = assembler.Parameter(Descriptor::kObject);
   Node* context = assembler.Parameter(Descriptor::kContext);
 
   assembler.Return(
@@ skipping 45 matching lines @@
   CodeStubAssembler assembler(state);
 
   Node* object = assembler.Parameter(Descriptor::kObject);
   Node* context = assembler.Parameter(Descriptor::kContext);
 
   assembler.Return(assembler.GetSuperConstructor(object, context));
 }
 
 }  // namespace internal
 }  // namespace v8