[promises] Simplify PromiseSetHasHandler

src/builtins/builtins-promise.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-promise.h"
 #include "src/builtins/builtins-utils.h"
 #include "src/builtins/builtins.h"
 #include "src/code-factory.h"
 #include "src/code-stub-assembler.h"
 #include "src/promise-utils.h"
@@ skipping 76 matching lines @@
   Bind(&out);
   return var_value_map.value();
 }
 
 Node* PromiseBuiltinsAssembler::PromiseHasHandler(Node* promise) {
   Node* const flags = LoadObjectField(promise, JSPromise::kFlagsOffset);
   return IsSetWord(SmiUntag(flags), 1 << JSPromise::kHasHandlerBit);
 }
 
 void PromiseBuiltinsAssembler::PromiseSetHasHandler(Node* promise) {
-  Node* const flags =
-      SmiUntag(LoadObjectField(promise, JSPromise::kFlagsOffset));
+  Node* const flags = LoadObjectField(promise, JSPromise::kFlagsOffset);
   Node* const new_flags =
-      WordOr(flags, IntPtrConstant(1 << JSPromise::kHasHandlerBit));
-  StoreObjectField(promise, JSPromise::kFlagsOffset, SmiTag(new_flags));
+      SmiOr(flags, SmiConstant(1 << JSPromise::kHasHandlerBit));
+  StoreObjectFieldNoWriteBarrier(promise, JSPromise::kFlagsOffset, new_flags);
 }
 
 Node* PromiseBuiltinsAssembler::SpeciesConstructor(Node* context, Node* object,
                                                    Node* default_constructor) {
   Isolate* isolate = this->isolate();
   Variable var_result(this, MachineRepresentation::kTagged);
   var_result.Bind(default_constructor);
 
   // 2. Let C be ? Get(O, "constructor").
   Node* const constructor_str =
@@ skipping 874 matching lines @@
     CallRuntime(Runtime::kDebugPopPromise, context);
     Goto(&out);
 
     Bind(&out);
     Return(UndefinedConstant());
   }
 }
 
 }  // namespace internal
 }  // namespace v8