[builtins] Migrate the Object constructor from JS to CSA.

This speeds up the baseline performance of Object by 20%.

With this change, the callViaObject when run with --noopt
goes from 10718ms to 8577ms on the benchmark from:
http://benediktmeurer.de/2017/08/31/object-constructor-calls-in-webpack-bundles

Bug: v8:6772
Change-Id: Id0e54ba44204a1700885185ec360e1c56834fb73
Reviewed-on: https://chromium-review.googlesource.com/654900Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47888}

src/bootstrapper.cc

@@ -691,9 +691,13 @@ void Genesis::CreateObjectFunction(Handle<JSFunction> empty_function) {
   int unused = JSObject::kInitialGlobalObjectUnusedPropertiesCount;
   int instance_size = JSObject::kHeaderSize + kPointerSize * unused;
 
-  Handle<JSFunction> object_fun =
-      CreateFunction(isolate_, factory->Object_string(), JS_OBJECT_TYPE,
-                     instance_size, factory->null_value(), Builtins::kIllegal);
+  Handle<JSFunction> object_fun = CreateFunction(
+      isolate_, factory->Object_string(), JS_OBJECT_TYPE, instance_size,
+      factory->null_value(), Builtins::kObjectConstructor);
+  object_fun->shared()->set_length(1);
+  object_fun->shared()->DontAdaptArguments();
+  object_fun->shared()->set_construct_stub(
+      *BUILTIN_CODE(isolate_, ObjectConstructor_ConstructStub));
   native_context()->set_object_function(*object_fun);
 
   {

src/builtins/builtins-constructor-gen.cc

@@ -795,5 +795,51 @@ TF_BUILTIN(CreateEmptyObjectLiteral, ConstructorBuiltinsAssembler) {
   Node* result = EmitCreateEmptyObjectLiteral(context);
   Return(result);
 }
+
+TF_BUILTIN(ObjectConstructor, ConstructorBuiltinsAssembler) {
+  int const kValueArg = 0;
+  Node* argc =
+      ChangeInt32ToIntPtr(Parameter(BuiltinDescriptor::kArgumentsCount));
+  CodeStubArguments args(this, argc);
+  Node* value = args.GetOptionalArgumentValue(kValueArg);
+  Node* context = Parameter(BuiltinDescriptor::kContext);
+
+  CSA_ASSERT(this, IsUndefined(Parameter(BuiltinDescriptor::kNewTarget)));
+
+  Label return_to_object(this);
+
+  GotoIf(Word32And(IsNotUndefined(value), IsNotNull(value)), &return_to_object);
+
+  args.PopAndReturn(EmitCreateEmptyObjectLiteral(context));
+
+  BIND(&return_to_object);
+  args.PopAndReturn(CallBuiltin(Builtins::kToObject, context, value));
+}
+
+TF_BUILTIN(ObjectConstructor_ConstructStub, ConstructorBuiltinsAssembler) {
+  int const kValueArg = 0;
+  Node* argc =
+      ChangeInt32ToIntPtr(Parameter(BuiltinDescriptor::kArgumentsCount));
+  CodeStubArguments args(this, argc);
+  Node* value = args.GetOptionalArgumentValue(kValueArg);
+
+  Node* target = LoadFromFrame(StandardFrameConstants::kFunctionOffset,
+                               MachineType::TaggedPointer());
+  Node* new_target = Parameter(BuiltinDescriptor::kNewTarget);
+  Node* context = Parameter(BuiltinDescriptor::kContext);
+
+  CSA_ASSERT(this, IsNotUndefined(new_target));
+
+  Label return_to_object(this);
+
+  GotoIf(Word32And(WordEqual(target, new_target),
+                   Word32And(IsNotUndefined(value), IsNotNull(value))),
+         &return_to_object);
+  args.PopAndReturn(EmitFastNewObject(context, target, new_target));
+
+  BIND(&return_to_object);
+  args.PopAndReturn(CallBuiltin(Builtins::kToObject, context, value));
+}
+
 }  // namespace internal
 }  // namespace v8

src/builtins/builtins-definitions.h

@@ -683,6 +683,9 @@ namespace internal {
   TFC(StrictEqual, Compare, 1)                                                 \
                                                                                \
   /* Object */                                                                 \
+  TFJ(ObjectConstructor, SharedFunctionInfo::kDontAdaptArgumentsSentinel)      \
+  TFJ(ObjectConstructor_ConstructStub,                                         \
+      SharedFunctionInfo::kDontAdaptArgumentsSentinel)                         \
   CPP(ObjectAssign)                                                            \
   /* ES #sec-object.create */                                                  \
   TFJ(ObjectCreate, SharedFunctionInfo::kDontAdaptArgumentsSentinel)           \

src/debug/debug-evaluate.cc

@@ -448,6 +448,7 @@ bool BuiltinHasNoSideEffect(Builtins::Name id) {
   switch (id) {
     // Whitelist for builtins.
     // Object builtins.
+    case Builtins::kObjectConstructor:
     case Builtins::kObjectCreate:
     case Builtins::kObjectEntries:
     case Builtins::kObjectGetOwnPropertyDescriptor:

src/js/v8natives.js

@@ -35,23 +35,6 @@ function GetMethod(obj, p) {
   throw %make_type_error(kCalledNonCallable, typeof func);
 }
 
-// ES6 19.1.1.1
-function ObjectConstructor(x) {
-  if (GlobalObject != new.target && !IS_UNDEFINED(new.target)) {
-    return this;
-  }
-  if (IS_NULL(x) || IS_UNDEFINED(x)) return {};
-  return TO_OBJECT(x);
-}
-
-
-// ----------------------------------------------------------------------------
-// Object
-
-%SetNativeFlag(GlobalObject);
-%SetCode(GlobalObject, ObjectConstructor);
-
-
 // ----------------------------------------------------------------------------
 // Iterator related spec functions.
 

test/unittests/compiler/js-create-lowering-unittest.cc

@@ -93,7 +93,7 @@ TEST_F(JSCreateLoweringTest, JSCreateArgumentsInlinedMapped) {
   Node* const closure = Parameter(Type::Any());
   Node* const context = UndefinedConstant();
   Node* const effect = graph()->start();
-  Handle<SharedFunctionInfo> shared(isolate()->object_function()->shared());
+  Handle<SharedFunctionInfo> shared(isolate()->script_function()->shared());
   Node* const frame_state_outer = FrameState(shared, graph()->start());
   Node* const frame_state_inner = FrameState(shared, frame_state_outer);
   Reduction r = Reduce(graph()->NewNode(
@@ -111,7 +111,7 @@ TEST_F(JSCreateLoweringTest, JSCreateArgumentsInlinedUnmapped) {
   Node* const closure = Parameter(Type::Any());
   Node* const context = UndefinedConstant();
   Node* const effect = graph()->start();
-  Handle<SharedFunctionInfo> shared(isolate()->object_function()->shared());
+  Handle<SharedFunctionInfo> shared(isolate()->script_function()->shared());
   Node* const frame_state_outer = FrameState(shared, graph()->start());
   Node* const frame_state_inner = FrameState(shared, frame_state_outer);
   Reduction r = Reduce(graph()->NewNode(
@@ -129,7 +129,7 @@ TEST_F(JSCreateLoweringTest, JSCreateArgumentsInlinedRestArray) {
   Node* const closure = Parameter(Type::Any());
   Node* const context = UndefinedConstant();
   Node* const effect = graph()->start();
-  Handle<SharedFunctionInfo> shared(isolate()->object_function()->shared());
+  Handle<SharedFunctionInfo> shared(isolate()->script_function()->shared());
   Node* const frame_state_outer = FrameState(shared, graph()->start());
   Node* const frame_state_inner = FrameState(shared, frame_state_outer);
   Reduction r = Reduce(graph()->NewNode(