/* $Id: memset.S,v 1.1 2000/04/14 16:49:01 mjd Exp $ | |
* | |
* "memset" implementation of SuperH | |
* | |
* Copyright (C) 1999 Niibe Yutaka | |
* | |
*/ | |
/* | |
* void *memset(void *s, int c, size_t n); | |
*/ | |
#include <linux/linkage.h> | |
ENTRY(memset) | |
tst r6,r6 | |
bt/s 5f ! if n=0, do nothing | |
add r6,r4 | |
mov #12,r0 | |
cmp/gt r6,r0 | |
bt/s 4f ! if it's too small, set a byte at once | |
mov r4,r0 | |
and #3,r0 | |
cmp/eq #0,r0 | |
bt/s 2f ! It's aligned | |
sub r0,r6 | |
1: | |
dt r0 | |
bf/s 1b | |
mov.b r5,@-r4 | |
2: ! make VVVV | |
extu.b r5,r5 | |
swap.b r5,r0 ! V0 | |
or r0,r5 ! VV | |
swap.w r5,r0 ! VV00 | |
or r0,r5 ! VVVV | |
! | |
mov r6,r0 | |
shlr2 r0 | |
shlr r0 ! r0 = r6 >> 3 | |
3: | |
dt r0 | |
mov.l r5,@-r4 ! set 8-byte at once | |
bf/s 3b | |
mov.l r5,@-r4 | |
! | |
mov #7,r0 | |
and r0,r6 | |
tst r6,r6 | |
bt 5f | |
! fill bytes | |
4: | |
dt r6 | |
bf/s 4b | |
mov.b r5,@-r4 | |
5: | |
rts | |
mov r4,r0 |