This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

[patch] RFC: ix86 / x86_64 register pressure aware scheduling


Hello,

The attached patch enables register pressure aware scheduling for the
ix86 and x86_64 targets. It uses the optimistic algorithm to avoid
being overly conservative.

This is the same as what other CISCy targets, like s390, also do.

The motivation for this patch is the excessive spilling I've observed
in a few test cases with relatively large basic blocks, e.g.
encryption algorithms and codecs. The patch passes bootstrap+testing
on x86_64-unknown-linux-gnu and i686-unknown-linux-gnu, with a few new
failures due to PR56950.

Off-list, Uros, Honza and others have already looked at the patch and
benchmarked it. For x86_64 there is an overall improvement for SPEC2k
except that lucas regresses, but such a preliminary result is IMHO
very promising.

Comments/suggestions welcome :-)

Ciao!
Steven

Attachment: i386_sched_pressure.diff.txt
Description: Text document


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]