>On Mon, 28 Mar 2005, James E Wilson wrote: >> Steven Bosscher wrote: >>> OK, so I know this is not a popular subject, but can we *please* stop >>> working on loop.c and focus on getting the new RTL and tree loop passes >>> to do what we want? >> I don't think anyone is objecting to this. [...] >> I would however make a distinction here between new development work and >> maintenance. It would be better if new development work happened in the new >> loop optimizer. However, we still need to do maintenance work in loop.c. > >...and since Canqun reported 2.5% improvement on SPEC CFP2000 on ia64 with >his current patch, I really think we should consider it. >
Besides this, I¡¯ve got another patch for improving
general induction variable optimizations defined in
loop.c. With these two patches and properly setting
the loop unrolling parameters, the tests of both NAS
and SPEC CPU2000 benchmarks on IA-64 1GHz system show
a good result.
1. The following table shows the test result of NAS
benchmarks:
Gcc-20050404 Gcc-20050404 Ratio
+ Optimized.
Bt.W 22.16s 22.68s 0.98
Cg.A 9.23s 7.45s 1.24
Ep.W 12.3s 11.97s 1.03
Ft.A 38.41s 25.98s 1.48
Is.B 34.94s 33.47s 1.04
Lu.W 32.93s 31.59s 1.04
Mg.A 21.91s 14.64s 1.50
Sp.W 59.71s 55.67s 1.07
Geomean 1.16
"Gcc-20050404" is the GCC mainline version dated on
April 4, 2005. It includes my previous patch of
RECORD_TYPE for COMMON blocks without equivalence
objects. The compile options for ¡°Gcc-20050404¡± is
¡°-O3 -funroll-loops -fprefetch-loop-arrays¡±, and ¡°-
O3 -funroll-loops -fprefetch-loop-arrays --param max-
unrolled-insns=600 --param max-average-unrolled-
insns=320¡± for¡°Gcc-20050404+Optimized¡±.
2. The SPEC CFP2000 test uses the same options as
above.
¡°Gcc-20050404¡± got 426 SPEC ratio, and ¡°Gcc-
20050404 + Optimized¡± got 459 SPEC ratio. You can
download the attachments to see more details. And if
the address giv splitting were not miss in the new
loop unroller, the SPEC ratio up to 513 can be
expected.
>We all know how hard it is to get this kind of
improvement on any of the
>SPECs -- and in fact improving the current optimizers
will make raise >the
>bar for the new ones. ;-)
>
>Question is: who is going review/potentially approve
this patch?
>
>Gerald
Canqun Yang
Creative Compiler Research Group.
National University of Defense Technology, China.
CFP2000.154.pdf
Description: Adobe PDF document
CFP2000.155.pdf
Description: Adobe PDF document
