From bug 643615 comment 5. This is needed for deltablue and richards. We think the extended equality hook (which needs to be tested for on the fast path) might be part of the problem, but we're not sure it's the only problem. function A() { } function f() { var a = new A(); var b = new A(); //var b = a; var c; for (var j = 0; j < 10000000; ++j) { c = a == b; } } var t0 = new Date; f(); print(new Date - t0);

FWIW, on the TI branch we are as fast as V8 on this testcase.

Comment 1, we merged TI