1// Copyright 2013 the V8 project authors. All rights reserved.
2// Redistribution and use in source and binary forms, with or without
3// modification, are permitted provided that the following conditions are
4// met:
5//
6//     * Redistributions of source code must retain the above copyright
7//       notice, this list of conditions and the following disclaimer.
8//     * Redistributions in binary form must reproduce the above
9//       copyright notice, this list of conditions and the following
10//       disclaimer in the documentation and/or other materials provided
11//       with the distribution.
12//     * Neither the name of Google Inc. nor the names of its
13//       contributors may be used to endorse or promote products derived
14//       from this software without specific prior written permission.
15//
16// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
28// Flags: --allow-natives-syntax
29
30// Test the performance.now() function of d8.  This test only makes sense with
31// d8.
32
33if (this.performance && performance.now) {
34  (function run() {
35    var start_test = performance.now();
36    // Let the retry run for maximum 100ms to reduce flakiness.
37    for (var start = performance.now();
38        start - start_test < 100;
39        start = performance.now()) {
40      var end = performance.now();
41      assertTrue(start >= start_test);
42      assertTrue(end >= start);
43      while (end - start == 0) {
44        var next = performance.now();
45        assertTrue(next >= end);
46        end = next;
47      }
48      if (end - start <= 1) {
49        // Found (sub-)millisecond granularity.
50        return;
51      } else {
52        print("Timer difference too big: " + (end - start) + "ms");
53      }
54    }
55    assertTrue(false);
56  })()
57}
58