js/src/jit-test/tests/basic/testGuardCalleeSneakAttack2.js@6474c204b198 (annotated)
js/src/jit-test/tests/basic/testGuardCalleeSneakAttack2.js
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
| michael@0 | 1 | function loop(f, expected) { |
| michael@0 | 2 | // This is the loop that breaks us. |
| michael@0 | 3 | // At record time, f's parent is a Call object with no fp. |
| michael@0 | 4 | // At second execute time, it is a Call object with fp, |
| michael@0 | 5 | // and all the Call object's dslots are still JSVAL_VOID. |
| michael@0 | 6 | for (var i = 0; i < 9; i++) |
| michael@0 | 7 | assertEq(f(), expected); |
| michael@0 | 8 | } |
| michael@0 | 9 | |
| michael@0 | 10 | function C(bad) { |
| michael@0 | 11 | var x = bad; |
| michael@0 | 12 | function f() { |
| michael@0 | 13 | return x; // We trick TR::callProp() into emitting code that gets |
| michael@0 | 14 | // JSVAL_VOID (from the Call object's dslots) |
| michael@0 | 15 | // rather than the actual value (true or false). |
| michael@0 | 16 | } |
| michael@0 | 17 | if (bad) |
| michael@0 | 18 | void (f + "a!"); |
| michael@0 | 19 | return f; |
| michael@0 | 20 | } |
| michael@0 | 21 | |
| michael@0 | 22 | var obj = { |
| michael@0 | 23 | }; |
| michael@0 | 24 | |
| michael@0 | 25 | // Warm up and trace with C's Call object entrained but its stack frame gone. |
| michael@0 | 26 | loop(C.call(obj, false), false); |
| michael@0 | 27 | |
| michael@0 | 28 | // Sneaky access to f via a prototype method called implicitly by operator +. |
| michael@0 | 29 | Function.prototype.toString = function () { loop(this, true); return "hah"; }; |
| michael@0 | 30 | |
| michael@0 | 31 | // Fail hard if we don't handle the implicit call out of C to F.p.toString. |
| michael@0 | 32 | C.call(obj, true); |
