Ping: patch to remove the old RA

Vladimir Makarov vmakarov@redhat.com
Thu Jan 29 21:10:00 GMT 2009


H.J. Lu wrote:
> On Thu, Jan 29, 2009 at 12:32 PM, H.J. Lu <hjl.tools@gmail.com> wrote:
>   
>>
>>> No, regmove for IRA does the same as before the patch.
>>>
>>>
>>>       
>> Revision 143757 changed regmove.c:
>>
>>       /* We need fewer optimizations for IRA.  */
>> -      if ((! flag_regmove || flag_ira) && pass >= flag_expensive_optimizations)
>> +      if (! flag_regmove && pass >= flag_expensive_optimizations)
>>        goto done;
>>
>> Since flag_regmove is 1 at -O2, remove  flag_ira does change IRA code
>> generation.
>>
>>     
>
> FWIW, I am not against this change since it does fixes PR 37364.
> I am running SPEC CPU 2K/2006 with revision 143757 on ia32
> and Intel64.
>
>   
I am not against it too :)  Actually it was my intention to do this 
originally.  No harm to do some optimizations twice.  I only wanted to 
remove  optimizations which is done by IRA.   But it looks that I did a 
stupid mistake and switched the second pass off for optimizations which 
should work with IRA.

I think the current code should stay unless there is no big performance 
regressions.

Thanks, H.J., for finding this issue.



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