v8/test/mjsunit/es6/call-with-spread-modify-next.js
Peter Marshall 2237106ae2 [turbo] Reduce CallWithSpread where iteration is not observable.
Where the arguments have already been inlined, we can replace these
calls with a direct call. We have to make sure that the iteration over
the arguments is not observable.

Also factor out the large chunk of logic shared with
ReduceJSConstructWithSpread.

BUG=v8:5932

Change-Id: I6c4fac670028fbd8ca82c4474d4392231573bc49
Reviewed-on: https://chromium-review.googlesource.com/439329
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43039}
2017-02-08 14:17:59 +00:00

43 lines
823 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);
}
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);
assertEquals(3, called);
assertEquals(2, r2);
})();