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comparison: js/src/jit-test/tests/basic/bug972961.js
js/src/jit-test/tests/basic/bug972961.js
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| -1:000000000000 | 0:ab4b39e71738 |
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| 1 // Bug 972961 - Test compiler with very long chains of property accesses | |
| 2 | |
| 3 // Return true if we can compile a chain of n property accesses, | |
| 4 // false if we cannot. Throw if compilation fails in an unexpected way. | |
| 5 function test(n) { | |
| 6 print("testing " + n); | |
| 7 try { | |
| 8 eval('if (false) {' + Array(n).join(("a.")) + 'a}'); | |
| 9 } catch (exc) { | |
| 10 // Expected outcome if the expression is too deeply nested is an InternalError. | |
| 11 if (!(exc instanceof InternalError)) | |
| 12 throw exc; | |
| 13 print(exc.message); | |
| 14 return false; | |
| 15 } | |
| 16 print("no exception"); | |
| 17 return true; | |
| 18 } | |
| 19 | |
| 20 // Find out how long a chain is enough to break the compiler. | |
| 21 var n = 4, LIMIT = 0x000fffff; | |
| 22 var lo = 1, hi = 1; | |
| 23 while (n <= LIMIT && test(n)) { | |
| 24 lo = n; | |
| 25 n *= 4; | |
| 26 } | |
| 27 | |
| 28 // Using binary search, find a pass/fail boundary (in order to | |
| 29 // test the edge case). | |
| 30 if (n <= LIMIT) { | |
| 31 hi = n; | |
| 32 while (lo !== hi) { | |
| 33 var mid = Math.floor((lo + hi) / 2); | |
| 34 if (test(mid)) | |
| 35 lo = mid + 1; | |
| 36 else | |
| 37 hi = mid; | |
| 38 } | |
| 39 print((lo - 1) + " attributes should be enough for anyone"); | |
| 40 } |
