| /* $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 |