-freduce-all-*

[Michael T. Babcock]

I was doing some work with ATLAS and running the author's xmm_gc3 
benchmark and noticed the comments associated with the 
-freduce-all-(movables|givs) options.  For what its worth (best speeds 
are cited):

Without: (/usr/local/gcc-3.4.2/bin/gcc -O3 -fomit-frame-pointer 
-fforce-addr -march=pentium -mtune=athlon -ftracer -funit-at-a-time  
-fbranch-probabilities -fsched2-use-superblocks)
./xmm_gc3
ALGORITHM     NB   REPS        TIME      MFLOPS
=========  =====  =====  ==========  ==========
atlasmm       60   3000       0.700     1851.71

With: (/usr/local/gcc-3.4.2/bin/gcc -O3 -fomit-frame-pointer 
-fforce-addr -march=pentium -mtune=athlon -ftracer -funit-at-a-time  
-fbranch-probabilities -fmove-all-movables -freduce-all-giv)
./xmm_gc3
ALGORITHM     NB   REPS        TIME      MFLOPS
=========  =====  =====  ==========  ==========
atlasmm       60   3000       0.762     1701.05

Each compile above was preceded by one with "-ftracer| -fprofile-arcs 
-fprofile-values -fvpt" and then the program was run three times before 
recompiling with the above options and re-running.

Please CC on replies/comments.

Also note, I have no connection to the authorship of the benchmarks or 
software above.
-- 
Michael T. Babcock
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