1/*
2 * Copyright (c) 2015 ARM Ltd
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 * 3. The name of the company may not be used to endorse or promote
14 *    products derived from this software without specific prior written
15 *    permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY ARM LTD ``AS IS'' AND ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL ARM LTD BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
22 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
23 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
24 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
25 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
26 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#include <picolibc.h>
30
31	.arm
32	.syntax unified
33	.global memset
34	.type	memset, %function
35memset:
36	tst	r0, #3
37	stmfd	sp!, {r4, lr}
38	beq	10f
39	cmp	r2, #0
40	sub	r2, r2, #1
41	beq	9f
42	and	ip, r1, #255
43	mov	r3, r0
44	b	2f
451:
46	cmp	r2, #0
47	sub	r2, r2, #1
48	beq	9f
492:
50	strb	ip, [r3], #1
51	tst	r3, #3
52	bne	1b
533:
54	cmp	r2, #3
55	bls	7f
56	and	lr, r1, #255
57	orr	lr, lr, lr, asl #8
58	cmp	r2, #15
59	orr	lr, lr, lr, asl #16
60	bls	5f
61	mov	r4, r2
62	add	ip, r3, #16
634:
64	sub	r4, r4, #16
65	cmp	r4, #15
66	str	lr, [ip, #-16]
67	str	lr, [ip, #-12]
68	str	lr, [ip, #-8]
69	str	lr, [ip, #-4]
70	add	ip, ip, #16
71	bhi	4b
72	sub	ip, r2, #16
73	bic	ip, ip, #15
74	and	r2, r2, #15
75	add	ip, ip, #16
76	cmp	r2, #3
77	add	r3, r3, ip
78	bls	7f
795:
80	mov	r4, r3
81	mov	ip, r2
826:
83	sub	ip, ip, #4
84	cmp	ip, #3
85	str	lr, [r4], #4
86	bhi	6b
87	sub	ip, r2, #4
88	bic	ip, ip, #3
89	add	ip, ip, #4
90	add	r3, r3, ip
91	and	r2, r2, #3
927:
93	cmp	r2, #0
94	andne	r1, r1, #255
95	addne	r2, r3, r2
96	beq	9f
978:
98	strb	r1, [r3], #1
99	cmp	r3, r2
100	bne	8b
1019:
102	ldmfd	sp!, {r4, lr}
103	bx	lr
10410:
105	mov	r3, r0
106	b	3b
107	.size memset, . - memset
108