v8/test/mjsunit/es6/call-with-spread-modify-next.js
Mythri A 55e8d61391 [Test] Add %PrepareForOptimization in tests
With bytecode flushing and lazy feedback allocation, we need to call
%PrepareForOptimization before we call %OptimizeFunctionOnNextCall

Bug: v8:8801, v8:8394
Change-Id: I1f84477a8cef27b4cff61b54daf6fe1a9e5f8e76
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1591775
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61148}
2019-05-02 09:43:17 +00:00

46 lines
994 B
JavaScript

// Copyright 2017 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: --allow-natives-syntax
(function modifyNext() {
'use strict';
var a = [];
var ai = a[Symbol.iterator]();
var original_next = ai.__proto__['next'];
function maxWithZero(...args) {
return Math.max(0, ...args);
}
function testMax(x, y) {
return maxWithZero(x, y);
}
%PrepareFunctionForOptimization(testMax);
testMax(1, 2);
testMax(1, 2);
%OptimizeFunctionOnNextCall(testMax);
var r = testMax(1, 2);
assertEquals(2, r);
var called = 0;
Object.defineProperty(ai.__proto__, 'next', {
get: function() {
called++;
return original_next;
}
});
var r2 = testMax(1, 2);
// .next() is only loaded once during the iteration prologue (see
// https://github.com/tc39/ecma262/pull/988/ and v8:6861)
assertEquals(1, called);
assertEquals(2, r2);
})();