[builtins] Remove ArrayBufferConstructor_ConstructStub builtin

This brings us closer to our goal of deprecating the `construct_stub`
field in `SharedFunctionInfo`.

Bug: v8:7503
Change-Id: I0e995e6ed9e7c04990f76dd8fe8afaaa8d38294b
Reviewed-on: https://chromium-review.googlesource.com/940124
Commit-Queue: Mathias Bynens <mathias@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51629}

src/bootstrapper.cc

@@ -4463,8 +4463,7 @@ Handle<JSFunction> Genesis::CreateArrayBuffer(
       CreateFunction(isolate(), name, JS_ARRAY_BUFFER_TYPE,
                      JSArrayBuffer::kSizeWithEmbedderFields, 0, prototype,
                      Builtins::kArrayBufferConstructor);
-  Handle<Code> code =
-      BUILTIN_CODE(isolate(), ArrayBufferConstructor_ConstructStub);
+  Handle<Code> code = BUILTIN_CODE(isolate(), JSBuiltinsConstructStub);
   array_buffer_fun->shared()->SetConstructStub(*code);
   array_buffer_fun->shared()->DontAdaptArguments();
   array_buffer_fun->shared()->set_length(1);

src/builtins/builtins-arraybuffer.cc

@@ -23,17 +23,6 @@ namespace internal {
 // -----------------------------------------------------------------------------
 // ES6 section 21.1 ArrayBuffer Objects
 
-// ES6 section 24.1.2.1 ArrayBuffer ( length ) for the [[Call]] case.
-BUILTIN(ArrayBufferConstructor) {
-  HandleScope scope(isolate);
-  Handle<JSFunction> target = args.target();
-  DCHECK(*target == target->native_context()->array_buffer_fun() ||
-         *target == target->native_context()->shared_array_buffer_fun());
-  THROW_NEW_ERROR_RETURN_FAILURE(
-      isolate, NewTypeError(MessageTemplate::kConstructorNotFunction,
-                            handle(target->shared()->name(), isolate)));
-}
-
 namespace {
 
 Object* ConstructBuffer(Isolate* isolate, Handle<JSFunction> target,
@@ -62,24 +51,30 @@ Object* ConstructBuffer(Isolate* isolate, Handle<JSFunction> target,
 
 }  // namespace
 
-// ES6 section 24.1.2.1 ArrayBuffer ( length ) for the [[Construct]] case.
-BUILTIN(ArrayBufferConstructor_ConstructStub) {
+// ES #sec-arraybuffer-constructor
+BUILTIN(ArrayBufferConstructor) {
   HandleScope scope(isolate);
   Handle<JSFunction> target = args.target();
-  Handle<JSReceiver> new_target = Handle<JSReceiver>::cast(args.new_target());
-  Handle<Object> length = args.atOrUndefined(isolate, 1);
   DCHECK(*target == target->native_context()->array_buffer_fun() ||
          *target == target->native_context()->shared_array_buffer_fun());
-
-  Handle<Object> number_length;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, number_length,
-                                     Object::ToInteger(isolate, length));
-  if (number_length->Number() < 0.0) {
+  if (args.new_target()->IsUndefined(isolate)) {  // [[Call]]
     THROW_NEW_ERROR_RETURN_FAILURE(
-        isolate, NewRangeError(MessageTemplate::kInvalidArrayBufferLength));
+        isolate, NewTypeError(MessageTemplate::kConstructorNotFunction,
+                              handle(target->shared()->name(), isolate)));
+  } else {  // [[Construct]]
+    Handle<JSReceiver> new_target = Handle<JSReceiver>::cast(args.new_target());
+    Handle<Object> length = args.atOrUndefined(isolate, 1);
+
+    Handle<Object> number_length;
+    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, number_length,
+                                       Object::ToInteger(isolate, length));
+    if (number_length->Number() < 0.0) {
+      THROW_NEW_ERROR_RETURN_FAILURE(
+          isolate, NewRangeError(MessageTemplate::kInvalidArrayBufferLength));
+    }
+
+    return ConstructBuffer(isolate, target, new_target, number_length, true);
   }
-
-  return ConstructBuffer(isolate, target, new_target, number_length, true);
 }
 
 // This is a helper to construct an ArrayBuffer with uinitialized memory.

src/builtins/builtins-definitions.h

@@ -357,8 +357,8 @@ namespace internal {
   TFJ(ArrayIteratorPrototypeNext, 0)                                           \
                                                                                \
   /* ArrayBuffer */                                                            \
+  /* ES #sec-arraybuffer-constructor */                                        \
   CPP(ArrayBufferConstructor)                                                  \
-  CPP(ArrayBufferConstructor_ConstructStub)                                    \
   CPP(ArrayBufferConstructor_DoNotInitialize)                                  \
   CPP(ArrayBufferPrototypeGetByteLength)                                       \
   CPP(ArrayBufferIsView)                                                       \