v8/test/mjsunit/compiler/omit-default-ctors-array-iterator.js
Marja Hölttä ece2746346 [maglev] Omit calling default ctors
I.e., implement the Maglev handler for the FindNonDefaultConstructor
bytecode.

Bug: v8:13091
Change-Id: I6d9905227875fe4efd460434b650fc48d008e7bf
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3925196
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/main@{#83470}
2022-09-28 11:02:44 +00:00

34 lines
1.0 KiB
JavaScript

// Copyright 2022 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.
// Flags: --omit-default-ctors --allow-natives-syntax --turbofan
// Flags: --no-always-turbofan
// This behavior is not spec compliant, see crbug.com/v8/13249.
(function ArrayIteratorMonkeyPatched() {
let iterationCount = 0;
const oldIterator = Array.prototype[Symbol.iterator];
Array.prototype[Symbol.iterator] =
function () { ++iterationCount; return oldIterator.call(this); };
class A {}
class B extends A {}
class C extends B {}
%PrepareFunctionForOptimization(C);
new C();
%OptimizeFunctionOnNextCall(C);
// C default ctor doing "...args" and B default ctor doing "...args".
assertEquals(2, iterationCount);
new C();
// C default ctor doing "...args" and B default ctor doing "...args".
assertEquals(4, iterationCount);
assertTrue(isTurboFanned(C)); // No deopt.
Array.prototype[Symbol.iterator] = oldIterator;
})();