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2dcc3665ab
PR-URL: https://github.com/nodejs/node/pull/28016 Reviewed-By: Colin Ihrig <cjihrig@gmail.com> Reviewed-By: Refael Ackermann (רפאל פלחי) <refack@gmail.com> Reviewed-By: Rich Trott <rtrott@gmail.com> Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com> Reviewed-By: Jiawen Geng <technicalcute@gmail.com>
46 lines
994 B
JavaScript
46 lines
994 B
JavaScript
// Copyright 2017 the V8 project authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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// Flags: --allow-natives-syntax
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(function modifyNext() {
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'use strict';
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var a = [];
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var ai = a[Symbol.iterator]();
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var original_next = ai.__proto__['next'];
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function maxWithZero(...args) {
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return Math.max(0, ...args);
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}
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function testMax(x, y) {
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return maxWithZero(x, y);
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}
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%PrepareFunctionForOptimization(testMax);
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testMax(1, 2);
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testMax(1, 2);
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%OptimizeFunctionOnNextCall(testMax);
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var r = testMax(1, 2);
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assertEquals(2, r);
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var called = 0;
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Object.defineProperty(ai.__proto__, 'next', {
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get: function() {
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called++;
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return original_next;
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}
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});
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var r2 = testMax(1, 2);
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// .next() is only loaded once during the iteration prologue (see
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// https://github.com/tc39/ecma262/pull/988/ and v8:6861)
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assertEquals(1, called);
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assertEquals(2, r2);
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})();
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