michael@0: function f(o) {
michael@0:     var res = 0;
michael@0:     for (var i=0; i<110; i++) {
michael@0:         res += o.x;
michael@0:     }
michael@0:     return res;
michael@0: }
michael@0: 
michael@0: function O(x) {
michael@0:     if ([].length == 0) // Thwart definite slot analysis.
michael@0:         this.x = 10;
michael@0: }
michael@0: 
michael@0: var o = new O(true);
michael@0: f(o);
michael@0: 
michael@0: // Add a getter, this should invalidate the script containing the idempotent cache.
michael@0: var res = 0;
michael@0: o.__defineGetter__("x", function() { res++; });
michael@0: f(o);
michael@0: assertEq(res, 110);