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(parent: fe2a1bb) | patch
powerpc: ppc64le optimised word at a time
authorAnton Blanchard <anton@samba.org>
Thu, 18 Sep 2014 23:40:20 +0000 (09:40 +1000)
committerMichael Ellerman <mpe@ellerman.id.au>
Tue, 30 Sep 2014 04:59:13 +0000 (14:59 +1000)
commit8989aa4adacd02174d1f72a00af8d669934a2b7a
tree45c14574a1c98878425318ffb0854ded1ebbcc79tree | snapshot
parentfe2a1bb1dbff1bc7b8c24eb1f691a544488617facommit | diff
powerpc: ppc64le optimised word at a time

Use cmpb which compares each byte in two 64 bit values and
for each matching byte places 0xff in the target and 0x00
otherwise.

A simple hash_name microbenchmark:

http://ozlabs.org/~anton/junkcode/hash_name_bench.c

shows this version to be 10-20% faster than running the x86
version on POWER8, depending on the length.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
arch/powerpc/include/asm/word-at-a-time.h diff | blob | history
ep93xx device tree rework repo: git://git.maquefel.me/linux.git