v8/test/mjsunit/es9/object-spread-ic-dontenum-transition.js
Caitlin Potter fbcf0221fa [CloneObjectIC] add CSA implementation of slow case
The CSA implementation is a separate handler so that TF has the
opportunity to reduce to a direct call, skipping some of the dispatching
in the CloneObjectIC stub.

This patch moves the looping over a source object's keys and values into the
base CodeStubAssembler, so that it can be shared between ObjectAssignFast
and CloneObjectIC_Slow.

During each step of the loop, storing is delegated to a new SetPropertyInLiteral
helper in KeyedStoreGenericGenerator, which performs a store without consulting
the prototype chain, and automatically reconfigures accessors into data
properties regardless of their attributes.

BUG=v8:8067, v8:7611
R=ishell@chromium.org, jkummerow@chromium.org

Change-Id: I06ae89f37e9b4265aab67389cf68a96529f90578
Reviewed-on: https://chromium-review.googlesource.com/1182122
Commit-Queue: Caitlin Potter <caitp@igalia.com>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55806}
2018-09-11 20:43:53 +00:00

27 lines
862 B
JavaScript

// Copyright 2018 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.
(function testMegamorphicWithDontEnumTransition() {
function spread(o) { return { ...o }; }
// Set up transition tree
let obj = { ...{}, a: 0, b: 1, c: 2, };
Object.defineProperty(obj, "boom", { enumerable: false, configurable: true,
writable: true });
// make CloneObjectIC MEGAMORPHIC
spread(new Proxy({}, {}));
// Ensure we don't crash, and create the correct object
let result = spread({ a: 0, b: 1, c: 2, boom: 3 });
assertEquals({ a: 0, b: 1, c: 2, boom: 3 }, result);
assertEquals({
enumerable: true,
writable: true,
configurable: true,
value: 3,
}, Object.getOwnPropertyDescriptor(result, "boom"));
})();