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

Vladimir Kozlov vladimir.kozlov at
Fri May 6 11:14:55 PDT 2011

Typo "it case" -> "in case" in both comments. Otherwise good.


Igor Veresov wrote:
> On 5/6/11 9:37 AM, Tom Rodriguez wrote:
>> 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:
>>> 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.
> Good point.
> Here's the new webrev: 
> Vladimir, I've also added comments.
> Thanks,
> igor

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