[builtins] Remove DataViewConstructor_ConstructStub builtin

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

Bug: v8:7503
Change-Id: I9502246f5e463e487a989ab7f8c96c008f0fa9d9
Reviewed-on: https://chromium-review.googlesource.com/941143
Commit-Queue: Mathias Bynens <mathias@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51634}

src/bootstrapper.cc

@@ -3035,7 +3035,7 @@ void Genesis::InitializeGlobal(Handle<JSGlobalObject> global_object,
     InstallWithIntrinsicDefaultProto(isolate, data_view_fun,
                                      Context::DATA_VIEW_FUN_INDEX);
     data_view_fun->shared()->SetConstructStub(
-        *BUILTIN_CODE(isolate, DataViewConstructor_ConstructStub));
+        *BUILTIN_CODE(isolate, JSBuiltinsConstructStub));
     data_view_fun->shared()->set_length(3);
     data_view_fun->shared()->DontAdaptArguments();
 

src/builtins/builtins-dataview.cc

@@ -14,20 +14,17 @@ namespace v8 {
 namespace internal {
 
 // -----------------------------------------------------------------------------
-// ES6 section 24.2 DataView Objects
+// ES #sec-dataview-objects
 
-// ES6 section 24.2.2 The DataView Constructor for the [[Call]] case.
+// ES #sec-dataview-constructor
 BUILTIN(DataViewConstructor) {
   HandleScope scope(isolate);
+  if (args.new_target()->IsUndefined(isolate)) {  // [[Call]]
     THROW_NEW_ERROR_RETURN_FAILURE(
-      isolate,
-      NewTypeError(MessageTemplate::kConstructorNotFunction,
-                   isolate->factory()->NewStringFromAsciiChecked("DataView")));
-}
-
-// ES6 section 24.2.2 The DataView Constructor for the [[Construct]] case.
-BUILTIN(DataViewConstructor_ConstructStub) {
-  HandleScope scope(isolate);
+        isolate, NewTypeError(MessageTemplate::kConstructorNotFunction,
+                              isolate->factory()->NewStringFromAsciiChecked(
+                                  "DataView")));
+  } else {  // [[Construct]]
     Handle<JSFunction> target = args.target();
     Handle<JSReceiver> new_target = Handle<JSReceiver>::cast(args.new_target());
     Handle<Object> buffer = args.atOrUndefined(isolate, 1);
@@ -43,20 +40,20 @@ BUILTIN(DataViewConstructor_ConstructStub) {
     }
     Handle<JSArrayBuffer> array_buffer = Handle<JSArrayBuffer>::cast(buffer);
 
-  // 4. Let offset be ToIndex(byteOffset).
+    // 4. Let offset be ? ToIndex(byteOffset).
     Handle<Object> offset;
     ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
         isolate, offset,
         Object::ToIndex(isolate, byte_offset, MessageTemplate::kInvalidOffset));
 
     // 5. If IsDetachedBuffer(buffer) is true, throw a TypeError exception.
-  // We currently violate the specification at this point.
+    //    We currently violate the specification at this point. TODO: Fix that.
 
-  // 6. Let bufferByteLength be the value of buffer's [[ArrayBufferByteLength]]
-  // internal slot.
+    // 6. Let bufferByteLength be the value of buffer's
+    // [[ArrayBufferByteLength]] internal slot.
     double const buffer_byte_length = array_buffer->byte_length()->Number();
 
-  // 7. If offset > bufferByteLength, throw a RangeError exception
+    // 7. If offset > bufferByteLength, throw a RangeError exception.
     if (offset->Number() > buffer_byte_length) {
       THROW_NEW_ERROR_RETURN_FAILURE(
           isolate, NewRangeError(MessageTemplate::kInvalidOffset, offset));
@@ -64,15 +61,15 @@ BUILTIN(DataViewConstructor_ConstructStub) {
 
     Handle<Object> view_byte_length;
     if (byte_length->IsUndefined(isolate)) {
-    // 8. If byteLength is undefined, then
+      // 8. If byteLength is either not present or undefined, then
       //       a. Let viewByteLength be bufferByteLength - offset.
       view_byte_length =
           isolate->factory()->NewNumber(buffer_byte_length - offset->Number());
     } else {
       // 9. Else,
       //       a. Let viewByteLength be ? ToIndex(byteLength).
-    //       b. If offset+viewByteLength > bufferByteLength, throw a RangeError
-    //          exception
+      //       b. If offset+viewByteLength > bufferByteLength, throw a
+      //          RangeError exception.
       ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
           isolate, view_byte_length,
           Object::ToIndex(isolate, byte_length,
@@ -86,7 +83,6 @@ BUILTIN(DataViewConstructor_ConstructStub) {
     // 10. Let O be ? OrdinaryCreateFromConstructor(NewTarget,
     //     "%DataViewPrototype%", «[[DataView]], [[ViewedArrayBuffer]],
     //     [[ByteLength]], [[ByteOffset]]»).
-  // 11. Set O's [[DataView]] internal slot to true.
     Handle<JSObject> result;
     ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result,
                                        JSObject::New(target, new_target));
@@ -94,17 +90,18 @@ BUILTIN(DataViewConstructor_ConstructStub) {
       Handle<JSDataView>::cast(result)->SetEmbedderField(i, Smi::kZero);
     }
 
-  // 12. Set O's [[ViewedArrayBuffer]] internal slot to buffer.
+    // 11. Set O's [[ViewedArrayBuffer]] internal slot to buffer.
     Handle<JSDataView>::cast(result)->set_buffer(*array_buffer);
 
-  // 13. Set O's [[ByteLength]] internal slot to viewByteLength.
+    // 12. Set O's [[ByteLength]] internal slot to viewByteLength.
     Handle<JSDataView>::cast(result)->set_byte_length(*view_byte_length);
 
-  // 14. Set O's [[ByteOffset]] internal slot to offset.
+    // 13. Set O's [[ByteOffset]] internal slot to offset.
     Handle<JSDataView>::cast(result)->set_byte_offset(*offset);
 
-  // 15. Return O.
+    // 14. Return O.
     return *result;
+  }
 }
 
 // ES6 section 24.2.4.1 get DataView.prototype.buffer

src/builtins/builtins-definitions.h

@@ -434,8 +434,8 @@ namespace internal {
   CPP(ConsoleContext)                                                          \
                                                                                \
   /* DataView */                                                               \
+  /* ES #sec-dataview-constructor */                                           \
   CPP(DataViewConstructor)                                                     \
-  CPP(DataViewConstructor_ConstructStub)                                       \
   CPP(DataViewPrototypeGetBuffer)                                              \
   CPP(DataViewPrototypeGetByteLength)                                          \
   CPP(DataViewPrototypeGetByteOffset)                                          \