js/src/jit-test/tests/basic/testGuardCalleeSneakAttack.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 this.m = f;
michael@0 18 return f;
michael@0 19 }
michael@0 20
michael@0 21 var obj = {
michael@0 22 set m(f) {
michael@0 23 if (f()) // Call once to resolve x on the Call object,
michael@0 24 // for shape consistency. Otherwise loop gets
michael@0 25 // recorded twice.
michael@0 26 loop(f, true);
michael@0 27 }
michael@0 28 };
michael@0 29
michael@0 30 loop(C.call(obj, false), false);
michael@0 31 C.call(obj, true);

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