review(S): 7042153: guarantee(x_compare_res != Constant::not_comparable) failed: incomparable constants in IfOp

[Tom Rodriguez]

On May 5, 2011, at 10:46 PM, Igor Veresov wrote:

> In C1, during IfOp elimination we can try to fold and IfOp that has constant objects as an arguments to the condition that are unloaded (not known at compile time) and are going to be patched later.
> The solution is to check for such cases in make_ifop().
> 
> Webrev: http://cr.openjdk.java.net/~iveresov/7042153/webrev.00/
> 
> Tested with a short testcase, which I added to the regression suite.

I think instead of disallowing this case you can simply the optimization if not_comparable is returned.  not_comparable is a valid return value so I don't think it should be an error to get is back from compare.

tom

> 
> Thanks,
> igor