linux/arch/sh/lib/strlen.S
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

70 lines
789 B
ArmAsm

/* $Id: strlen.S,v 1.2 2001/06/29 14:07:15 gniibe Exp $
*
* "strlen" implementation of SuperH
*
* Copyright (C) 1999 Kaz Kojima
*
*/
/* size_t strlen (const char *s) */
#include <linux/linkage.h>
ENTRY(strlen)
mov r4,r0
and #3,r0
tst r0,r0
bt/s 1f
mov #0,r2
add #-1,r0
shll2 r0
shll r0
braf r0
nop
mov.b @r4+,r1
tst r1,r1
bt 8f
add #1,r2
mov.b @r4+,r1
tst r1,r1
bt 8f
add #1,r2
mov.b @r4+,r1
tst r1,r1
bt 8f
add #1,r2
1:
mov #0,r3
2:
mov.l @r4+,r1
cmp/str r3,r1
bf/s 2b
add #4,r2
add #-4,r2
#ifndef __LITTLE_ENDIAN__
swap.b r1,r1
swap.w r1,r1
swap.b r1,r1
#endif
extu.b r1,r0
tst r0,r0
bt/s 8f
shlr8 r1
add #1,r2
extu.b r1,r0
tst r0,r0
bt/s 8f
shlr8 r1
add #1,r2
extu.b r1,r0
tst r0,r0
bt 8f
add #1,r2
8:
rts
mov r2,r0