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Re: Ping: patch to remove the old RA


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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