diff options
| author | Austin Foxley <austinf@cetoncorp.com> | 2009-11-22 12:17:38 -0800 |
|---|---|---|
| committer | Austin Foxley <austinf@cetoncorp.com> | 2009-11-22 12:17:38 -0800 |
| commit | 5c9ef58ec4bcb2def9e30f0b156f9cfcb1d0d163 (patch) | |
| tree | f8f889678b653d5275c285a037b9b43f27a91192 /libc/string/sh/memchr.S | |
| parent | f757db2d319ccc5f7034165046fb2bb58901afb1 (diff) | |
sh: Add new optimisation to the SH4 memcpy
This optimization is based on prefetching and 64bit data transfer via FPU
(only for the little endianess)
Tests shows that:
----------------------------------------
Memory bandwidth | Gain
| sh4-300 | sh4-200
----------------------------------------
512 bytes to 16KiB | ~20% | ~25%
from 32KiB to 16MiB | ~190% | ~5%
----------------------------------------
Signed-off-by: Austin Foxley <austinf@cetoncorp.com>
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: Carmelo Amoroso <carmelo.amoroso@st.com>
Diffstat (limited to 'libc/string/sh/memchr.S')
| -rw-r--r-- | libc/string/sh/memchr.S | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/libc/string/sh/memchr.S b/libc/string/sh/memchr.S new file mode 100644 index 000000000..6b7142f69 --- /dev/null +++ b/libc/string/sh/memchr.S @@ -0,0 +1,30 @@ +/* $Id: memchr.S,v 1.1 2000/04/14 16:49:01 mjd Exp $ + * + * "memchr" implementation of SuperH + * + * Copyright (C) 1999 Niibe Yutaka + * + * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball. + */ + +/* + * void *memchr(const void *s, int c, size_t n); + */ + +#include <sysdep.h> + +ENTRY(memchr) + tst r6,r6 + bt/s 2f + exts.b r5,r5 +1: mov.b @r4,r1 + cmp/eq r1,r5 + bt/s 3f + dt r6 + bf/s 1b + add #1,r4 +2: mov #0,r4 +3: rts + mov r4,r0 +END(memchr) +libc_hidden_def (memchr) |