tools/perf/page_sets/tough_animation_cases/resources/perftesthelper.js

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4 (function(){
   5 'use strict';
   6
   7 if (window.PerfTestHelper) {
   8   return;
   9 }
  10 window.PerfTestHelper = {};
  11
  12 var randomSeed = 3384413;
  13 window.PerfTestHelper.random = function() {
  14     var temp = randomSeed;
  15     // Robert Jenkins' 32 bit integer hash function.
  16     temp = ((temp + 0x7ed55d16) + (temp << 12))  & 0xffffffff;
  17     temp = ((temp ^ 0xc761c23c) ^ (temp >>> 19)) & 0xffffffff;
  18     temp = ((temp + 0x165667b1) + (temp << 5))   & 0xffffffff;
  19     temp = ((temp + 0xd3a2646c) ^ (temp << 9))   & 0xffffffff;
  20     temp = ((temp + 0xfd7046c5) + (temp << 3))   & 0xffffffff;
  21     temp = ((temp ^ 0xb55a4f09) ^ (temp >>> 16)) & 0xffffffff;
  22     randomSeed = temp;
  23     return (randomSeed & 0xfffffff) / 0x10000000;
  24 };
  25
  26 })();