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1 // Copyright 2012 the V8 project authors. All rights reserved. | 1 // Copyright 2012 the V8 project authors. All rights reserved. |
2 // Redistribution and use in source and binary forms, with or without | 2 // Redistribution and use in source and binary forms, with or without |
3 // modification, are permitted provided that the following conditions are | 3 // modification, are permitted provided that the following conditions are |
4 // met: | 4 // met: |
5 // | 5 // |
6 // * Redistributions of source code must retain the above copyright | 6 // * Redistributions of source code must retain the above copyright |
7 // notice, this list of conditions and the following disclaimer. | 7 // notice, this list of conditions and the following disclaimer. |
8 // * Redistributions in binary form must reproduce the above | 8 // * Redistributions in binary form must reproduce the above |
9 // copyright notice, this list of conditions and the following | 9 // copyright notice, this list of conditions and the following |
10 // disclaimer in the documentation and/or other materials provided | 10 // disclaimer in the documentation and/or other materials provided |
11 // with the distribution. | 11 // with the distribution. |
12 // * Neither the name of Google Inc. nor the names of its | 12 // * Neither the name of Google Inc. nor the names of its |
13 // contributors may be used to endorse or promote products derived | 13 // contributors may be used to endorse or promote products derived |
14 // from this software without specific prior written permission. | 14 // from this software without specific prior written permission. |
15 // | 15 // |
16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS | 16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT | 17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR | 18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT | 19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, | 20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT | 21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | 22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | 23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | 24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | 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. | 26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
27 | 27 |
28 // Flags: --allow-natives-syntax | 28 // Flags: --expose-gc --allow-natives-syntax |
29 | 29 |
30 // The original problem from the bug: In the example below SMI check for b | 30 function test() { |
31 // generated for inlining of equals invocation (marked with (*)) will be hoisted | 31 var s1 = %NewString(26, true); |
32 // out of the loop across the typeof b === "object" condition and cause an | 32 for (i = 0; i < 26; i++) %_OneByteSeqStringSetChar(s1, i, i+65); |
33 // immediate deopt. Another problem here is that no matter how many time we | 33 assertEquals("ABCDEFGHIJKLMNOPQRSTUVWXYZ", s1); |
34 // deopt and reopt we will continue to produce the wrong code. | 34 %TruncateString(s1, 13); |
35 // | 35 assertEquals("ABCDEFGHIJKLM", s1); |
36 // The fix is to notice when a deopt and subsequent reopt doesn't find | 36 assertThrows(function() { %TruncateString(s1, 14) }); |
37 // additional type information, indicating that optimistic LICM should be | 37 assertThrows(function() { %TruncateString(s1, 0) }); |
38 // disabled during compilation. | |
39 | 38 |
40 function eq(a, b) { | 39 var s2 = %NewString(26, false); |
41 if (typeof b === "object") { | 40 for (i = 0; i < 26; i++) %_TwoByteSeqStringSetChar(s2, i, i+65); |
42 return b.equals(a); // (*) | 41 assertEquals("ABCDEFGHIJKLMNOPQRSTUVWXYZ", s2); |
| 42 %TruncateString(s2, 13); |
| 43 assertEquals("ABCDEFGHIJKLM", s2); |
| 44 |
| 45 var s3 = %NewString(26, false); |
| 46 for (i = 0; i < 26; i++) %_TwoByteSeqStringSetChar(s3, i, i+1000); |
| 47 for (i = 0; i < 26; i++) assertEquals(s3[i], String.fromCharCode(i+1000)); |
| 48 |
| 49 var a = []; |
| 50 for (var i = 0; i < 1000; i++) { |
| 51 var s = %NewString(10000, i % 2 == 1); |
| 52 a.push(s); |
43 } | 53 } |
44 return a === b; | 54 |
| 55 gc(); |
| 56 |
| 57 for (var i = 0; i < 1000; i++) { |
| 58 assertEquals(10000, a[i].length); |
| 59 %TruncateString(a[i], 5000); |
| 60 } |
| 61 |
| 62 gc(); |
| 63 |
| 64 for (var i = 0; i < 1000; i++) { |
| 65 assertEquals(5000, a[i].length); |
| 66 } |
45 } | 67 } |
46 | 68 |
47 Object.prototype.equals = function (other) { | |
48 return (this === other); | |
49 }; | |
50 | 69 |
51 function test() { | 70 test(); |
52 for (var i = 0; !eq(i, 10); i++) | |
53 ; | |
54 } | |
55 | |
56 eq({}, {}); | |
57 eq({}, {}); | |
58 eq(1, 1); | |
59 eq(1, 1); | |
60 test(); | 71 test(); |
61 %OptimizeFunctionOnNextCall(test); | 72 %OptimizeFunctionOnNextCall(test); |
62 test(); | 73 test(); |
63 %OptimizeFunctionOnNextCall(test); | |
64 // Second compilation should have noticed that LICM wasn't a good idea, and now | |
65 // function should no longer deopt when called. | |
66 test(); | |
67 assertTrue(2 != %GetOptimizationStatus(test)); | |
68 | 74 |
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