[12] RFR(M): 8210215: C2 should optimize trichotomy calculations

[Tobias Hartmann]

Thanks Vladimir!

Best regards,
Tobias

On 09.10.2018 19:35, Vladimir Kozlov wrote:
> Looks good.
> 
> Thanks,
> Vladimir
> 
> On 10/9/18 10:29 AM, Tobias Hartmann wrote:
>> Hi,
>>
>> I had an off thread discussion with John and he suggested the following changes in addition:
>> - Use randomization for integer values in the test
>> - Add some asserts and comments to improve readability
>> - Don't apply optimization to floating point compares because they don't obey trichotomy laws (for
>> example, NaN always compares to false)
>> - Handle the case where the merge result is BoolTest::illegal (just for robustness, I haven't seen
>> this ever during testing but it might show up when overflow tests mix with "normal" other tests)
>> - While testing, I found that we also have to add a call to add_users_to_worklist(iff1) to make sure
>> that the dead if is removed (otherwise we hit failures like JDK-8075922).
>>
>> Incremental webrev:
>> http://cr.openjdk.java.net/~thartmann/8210215/webrev.04_inc/
>>
>> Full webrev:
>> http://cr.openjdk.java.net/~thartmann/8210215/webrev.04/
>>
>> Best regards,
>> Tobias
>>