function get_value_undefined(o) { return o.value } function get_value_null(o) { return o.value } function get_value_int(o) { return o.value } function get_value_effectfull(o) { return o.value } var count = 0 var o_undefined = {value: undefined} var o_null = {value: null} var o_int = {value: 3} var o_effectfull = {} Object.defineProperty(o_effectfull, "value", { get: function () { count++; return undefined; } }); // compiled as undefined for(var i=0; i<42; i++) get_value_undefined(o_undefined) // compiled as null for(var i=0; i<42; i++) get_value_null(o_null) // compiled as int for(var i=0; i<42; i++) get_value_int(o_int) // compiled as effectfull property access for(var i=0; i<42; i++) get_value_effectfull(o_effectfull) // Note: // because of bug 715111 when there is an invalidation we have bogus values on the stack. // So we get wrong values. Therefor I run them twice. On as 'warmup'. Second time to test count = 0 assertEq(get_value_undefined(o_undefined), undefined); get_value_undefined(o_null) assertEq(get_value_undefined(o_null), null); get_value_undefined(o_int) assertEq(get_value_undefined(o_int), 3); get_value_undefined(o_effectfull) assertEq(get_value_undefined(o_effectfull), undefined); assertEq(get_value_undefined(o_undefined), undefined); assertEq(count, 2); count = 0 assertEq(get_value_null(o_null), null); get_value_null(o_undefined) assertEq(get_value_null(o_undefined), undefined); get_value_null(o_int) assertEq(get_value_null(o_int), 3); get_value_null(o_effectfull) assertEq(get_value_null(o_effectfull), undefined); assertEq(get_value_null(o_null), null); assertEq(count, 2); count = 0 assertEq(get_value_int(o_int), 3); get_value_int(o_null) assertEq(get_value_int(o_null), null); get_value_int(o_undefined) assertEq(get_value_int(o_undefined), undefined); get_value_int(o_effectfull) assertEq(get_value_int(o_effectfull), undefined); assertEq(get_value_int(o_int), 3); assertEq(count, 2); count = 0 assertEq(get_value_effectfull(o_effectfull), undefined); get_value_effectfull(o_null) assertEq(get_value_effectfull(o_null), null); get_value_effectfull(o_undefined) assertEq(get_value_effectfull(o_undefined), undefined); get_value_effectfull(o_int) assertEq(get_value_effectfull(o_int), 3); assertEq(get_value_effectfull(o_effectfull), undefined); assertEq(count, 2);