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// Presents opportunities for dead loop removal.
31
32function loop1() {
33  while (false) ;  // doesn't even loop.
34}
35
36function loop2() {
37  var i = 0;
38  while (i++ < 10) ;  // nothing in the body.
39}
40
41function loop3() {
42  for (var i = 0; i < 10; i++) ;  // nothing in the body.
43}
44
45function loop4() {
46  var a = 0;
47  for (var i = 0; i < 10; i++) a++;  // {a} is dead after the loop.
48}
49
50function loop5() {
51  var a = new Int32Array(4), sum = 0;
52  for (var i = 0; i < a.length; i++) {
53    // Involves only reads on typed arrays, and {i} doesn't overflow.
54    sum += a[i];
55  }
56}
57
58function loop6() {
59  var a = new Array(4), sum = 0;
60  for (var i = 0; i < a.length; i++) {
61    // Involves only in-bounds read on the array {a}.
62    // Have to prove that {a} doesn't have getters...?
63    sum += a[i];
64  }
65}
66
67function loop7() {
68  for (var i = 0; i < 10; i++) {
69    new Object();  // Have to prove the allocation doesn't escape.
70  }
71}
72
73function loop8() {
74  for (var i = 0; i < 10; i++) {
75    var x = {};  // Have to prove the allocation doesn't escape.
76  }
77}
78
79var loops = [loop1, loop2, loop3, loop4, loop5, loop6, loop7, loop8];
80
81for (var i = 0; i < loops.length; i++) {
82  var f = loops[i];
83  f();
84  f();
85  %OptimizeFunctionOnNextCall(f);
86  f();
87}
88