xref: /OK3568_Linux_fs/kernel/arch/sh/lib/strlen.S (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun/* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun/* $Id: strlen.S,v 1.2 2001/06/29 14:07:15 gniibe Exp $
3*4882a593Smuzhiyun *
4*4882a593Smuzhiyun * "strlen" implementation of SuperH
5*4882a593Smuzhiyun *
6*4882a593Smuzhiyun * Copyright (C) 1999  Kaz Kojima
7*4882a593Smuzhiyun *
8*4882a593Smuzhiyun */
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun/* size_t strlen (const char *s)  */
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun#include <linux/linkage.h>
13*4882a593SmuzhiyunENTRY(strlen)
14*4882a593Smuzhiyun	mov	r4,r0
15*4882a593Smuzhiyun	and	#3,r0
16*4882a593Smuzhiyun	tst	r0,r0
17*4882a593Smuzhiyun	bt/s	1f
18*4882a593Smuzhiyun	 mov	#0,r2
19*4882a593Smuzhiyun
20*4882a593Smuzhiyun	add	#-1,r0
21*4882a593Smuzhiyun	shll2	r0
22*4882a593Smuzhiyun	shll	r0
23*4882a593Smuzhiyun	braf	r0
24*4882a593Smuzhiyun	 nop
25*4882a593Smuzhiyun
26*4882a593Smuzhiyun	mov.b	@r4+,r1
27*4882a593Smuzhiyun	tst	r1,r1
28*4882a593Smuzhiyun	bt	8f
29*4882a593Smuzhiyun	add	#1,r2
30*4882a593Smuzhiyun
31*4882a593Smuzhiyun	mov.b	@r4+,r1
32*4882a593Smuzhiyun	tst	r1,r1
33*4882a593Smuzhiyun	bt	8f
34*4882a593Smuzhiyun	add	#1,r2
35*4882a593Smuzhiyun
36*4882a593Smuzhiyun	mov.b	@r4+,r1
37*4882a593Smuzhiyun	tst	r1,r1
38*4882a593Smuzhiyun	bt	8f
39*4882a593Smuzhiyun	add	#1,r2
40*4882a593Smuzhiyun
41*4882a593Smuzhiyun1:
42*4882a593Smuzhiyun	mov	#0,r3
43*4882a593Smuzhiyun2:
44*4882a593Smuzhiyun	mov.l	@r4+,r1
45*4882a593Smuzhiyun	cmp/str	r3,r1
46*4882a593Smuzhiyun	bf/s	2b
47*4882a593Smuzhiyun	 add	#4,r2
48*4882a593Smuzhiyun
49*4882a593Smuzhiyun	add	#-4,r2
50*4882a593Smuzhiyun#ifndef __LITTLE_ENDIAN__
51*4882a593Smuzhiyun	swap.b	r1,r1
52*4882a593Smuzhiyun	swap.w	r1,r1
53*4882a593Smuzhiyun	swap.b	r1,r1
54*4882a593Smuzhiyun#endif
55*4882a593Smuzhiyun	extu.b	r1,r0
56*4882a593Smuzhiyun	tst	r0,r0
57*4882a593Smuzhiyun	bt/s	8f
58*4882a593Smuzhiyun	 shlr8	r1
59*4882a593Smuzhiyun	add	#1,r2
60*4882a593Smuzhiyun	extu.b	r1,r0
61*4882a593Smuzhiyun	tst	r0,r0
62*4882a593Smuzhiyun	bt/s	8f
63*4882a593Smuzhiyun	 shlr8	r1
64*4882a593Smuzhiyun	add	#1,r2
65*4882a593Smuzhiyun	extu.b	r1,r0
66*4882a593Smuzhiyun	tst	r0,r0
67*4882a593Smuzhiyun	bt	8f
68*4882a593Smuzhiyun	add	#1,r2
69*4882a593Smuzhiyun8:
70*4882a593Smuzhiyun	rts
71*4882a593Smuzhiyun	 mov	r2,r0
72