[Bug c/30287] New: -fregmove produces slow code

[safari-ml-gcc-bugzilla-vgvbszlod4jrh2zwsefgqp4frqg4zc7fgobtxnvg at u dot safari dot iki dot fi]

$ gcc aes256.i -O2 ; ./a.out
min: 651 avg: 686 extra: 644 discarded: 6766/10000

$ gcc aes256.i -O2 -fno-regmove ; ./a.out
min: 385 avg: 387 extra: 756 discarded: 66/10000

aes_encrypt is the function which is being benchmarked...
aes256.i.bz2 is pretty big but I can't help it.

My CPU is Pentium D.


other gcc versions
regmove        1      0
gcc-2.95.3    572    387
gcc-3.0.4     570    376
gcc-3.1.1     565    365
gcc-3.2.3     569    367
gcc-3.3.5     477    351
gcc-3.4.6     494    350
gcc-4.0.3     651    385
gcc-4.1.1-20061220 (Red Hat 4.1.1-48)
              596    355

icc-9.1        ?     342


-- 
           Summary: -fregmove produces slow code
           Product: gcc
           Version: 4.0.3
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: safari-ml-gcc-bugzilla-
                    vgvbszlod4jrh2zwsefgqp4frqg4zc7fgobtxnvg at u dot safari
                    dot iki dot fi
GCC target triplet: i686-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30287