1/* Copyright (c) 2015 ARM Ltd.
2   All rights reserved.
3
4   Redistribution and use in source and binary forms, with or without
5   modification, are permitted provided that the following conditions are met:
6       * Redistributions of source code must retain the above copyright
7	 notice, this list of conditions and the following disclaimer.
8       * Redistributions in binary form must reproduce the above copyright
9	 notice, this list of conditions and the following disclaimer in the
10	 documentation and/or other materials provided with the distribution.
11       * Neither the name of the Linaro nor the
12	 names of its contributors may be used to endorse or promote products
13	 derived from this software without specific prior written permission.
14
15   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
18   A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT
19   HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
20   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
21   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
25   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.  */
26
27	.macro def_fn f p2align=0
28	.text
29	.p2align \p2align
30	.global \f
31	.type \f, %function
32\f:
33	.endm
34
35	.arch	armv4t
36	.eabi_attribute Tag_also_compatible_with, "\006\013" /* ARMv6-M.  */
37	.eabi_attribute Tag_ARM_ISA_use, 0
38	.thumb
39	.syntax unified
40
41def_fn	strlen p2align=1
42	movs	r3, #0
431:
44	ldrb	r2, [r0, r3]
45	adds	r3, r3, #1
46	cmp	r2, #0
47	bne	1b
48	subs	r0, r3, #1
49	bx	lr
50	.size	strlen, . - strlen
51