1/*-
2 * Copyright (c) 2005 Olivier Houchard
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <machine/asm.h>
28__FBSDID("$FreeBSD$");
29
30ENTRY(strlen)
31	mov	r1, #0
32	/* Check that the pointer is aligned on 32 bits. */
33	ands	r3, r0, #3
34	beq	.Loop
35	sub	r0, r0, r3
36	ldr	r2, [r0]
37	add	r0, r0, #4
38	cmp	r3, #2
39	blt	.Ldo_3
40	bgt	.Ldo_1
41	/* So that the N bit is set. */
42	cmp	r3, #0
43	b	.Ldo_2
44
45.Loop:
46	ldr	r2, [r0]
47	add	r0, r0, #4
48#ifndef __ARMEB__
49	ands	r3, r2, #0x000000ff
50#else
51	ands	r3, r2, #0xff000000
52#endif
53	addne	r1, r1, #1
54.Ldo_3:
55#ifndef __ARMEB__
56	andnes    r3, r2, #0x0000ff00
57#else
58  	andnes    r3, r2, #0x00ff0000
59#endif
60	addne     r1, r1, #1
61.Ldo_2:
62#ifndef __ARMEB__
63	andnes    r3, r2, #0x00ff0000
64#else
65	andnes    r3, r2, #0x0000ff00
66#endif
67	addne	r1, r1, #1
68.Ldo_1:
69#ifndef __ARMEB__
70	andnes	r3, r2, #0xff000000
71#else
72	andnes	r3, r2, #0x000000ff
73#endif
74	addne	r1, r1, #1
75	bne	.Loop
76.Lexit:
77	mov	r0, r1
78	RET
79