xref: /freebsd/lib/libc/arm/string/memset.S (revision 0957b409a90fd597c1e9124cbaf3edd2b488f4ac)
1/*	$NetBSD: memset.S,v 1.4 2003/10/14 07:51:45 scw Exp $	*/
2
3/*
4 * Copyright 2003 Wasabi Systems, Inc.
5 * All rights reserved.
6 *
7 * Written by Steve C. Woodford for Wasabi Systems, Inc.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 *    must display the following acknowledgement:
19 *      This product includes software developed for the NetBSD Project by
20 *      Wasabi Systems, Inc.
21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22 *    or promote products derived from this software without specific prior
23 *    written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35 * POSSIBILITY OF SUCH DAMAGE.
36 */
37/*
38 * Copyright (c) 1995 Mark Brinicombe.
39 * All rights reserved.
40 *
41 * Redistribution and use in source and binary forms, with or without
42 * modification, are permitted provided that the following conditions
43 * are met:
44 * 1. Redistributions of source code must retain the above copyright
45 *    notice, this list of conditions and the following disclaimer.
46 * 2. Redistributions in binary form must reproduce the above copyright
47 *    notice, this list of conditions and the following disclaimer in the
48 *    documentation and/or other materials provided with the distribution.
49 * 3. All advertising materials mentioning features or use of this software
50 *    must display the following acknowledgement:
51 *	This product includes software developed by Mark Brinicombe.
52 * 4. The name of the company nor the name of the author may be used to
53 *    endorse or promote products derived from this software without specific
54 *    prior written permission.
55 *
56 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
57 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
58 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
59 * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
60 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
61 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
62 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
63 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
64 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
65 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
66 * SUCH DAMAGE.
67 */
68
69#include <machine/asm.h>
70__FBSDID("$FreeBSD$");
71
72.syntax	unified
73
74/*
75 * memset: Sets a block of memory to the specified value
76 *
77 * On entry:
78 *   r0 - dest address
79 *   r1 - byte to write
80 *   r2 - number of bytes to write
81 *
82 * On exit:
83 *   r0 - dest address
84 */
85#ifdef _BZERO
86/* LINTSTUB: Func: void bzero(void *, size_t) */
87ENTRY(bzero)
88	mov	r3, #0x00
89#else
90/* LINTSTUB: Func: void *memset(void *, int, size_t) */
91ENTRY(memset)
92	and	r3, r1, #0xff		/* We deal with bytes */
93	mov	r1, r2
94#endif
95	cmp	r1, #0x04		/* Do we have less than 4 bytes */
96	mov	ip, r0
97	blt	.Lmemset_lessthanfour
98
99	/* Ok first we will word align the address */
100	ands	r2, ip, #0x03		/* Get the bottom two bits */
101	bne	.Lmemset_wordunaligned	/* The address is not word aligned */
102
103	/* We are now word aligned */
104.Lmemset_wordaligned:
105#ifndef _BZERO
106	orr	r3, r3, r3, lsl #8	/* Extend value to 16-bits */
107#endif
108#ifdef _ARM_ARCH_5E
109	tst	ip, #0x04		/* Quad-align for armv5e */
110#else
111	cmp	r1, #0x10
112#endif
113#ifndef _BZERO
114	orr	r3, r3, r3, lsl #16	/* Extend value to 32-bits */
115#endif
116#ifdef _ARM_ARCH_5E
117	itt	ne
118	subne	r1, r1, #0x04		/* Quad-align if necessary */
119	strne	r3, [ip], #0x04
120	cmp	r1, #0x10
121#endif
122	blt	.Lmemset_loop4		/* If less than 16 then use words */
123	mov	r2, r3			/* Duplicate data */
124	cmp	r1, #0x80		/* If < 128 then skip the big loop */
125	blt	.Lmemset_loop32
126
127	/* Do 128 bytes at a time */
128.Lmemset_loop128:
129	subs	r1, r1, #0x80
130#ifdef _ARM_ARCH_5E
131	itttt	ge
132	strdge	r2, [ip], #0x08
133	strdge	r2, [ip], #0x08
134	strdge	r2, [ip], #0x08
135	strdge	r2, [ip], #0x08
136	itttt	ge
137	strdge	r2, [ip], #0x08
138	strdge	r2, [ip], #0x08
139	strdge	r2, [ip], #0x08
140	strdge	r2, [ip], #0x08
141	itttt	ge
142	strdge	r2, [ip], #0x08
143	strdge	r2, [ip], #0x08
144	strdge	r2, [ip], #0x08
145	strdge	r2, [ip], #0x08
146	itttt	ge
147	strdge	r2, [ip], #0x08
148	strdge	r2, [ip], #0x08
149	strdge	r2, [ip], #0x08
150	strdge	r2, [ip], #0x08
151#else
152	stmiage	ip!, {r2-r3}
153	stmiage	ip!, {r2-r3}
154	stmiage	ip!, {r2-r3}
155	stmiage	ip!, {r2-r3}
156	stmiage	ip!, {r2-r3}
157	stmiage	ip!, {r2-r3}
158	stmiage	ip!, {r2-r3}
159	stmiage	ip!, {r2-r3}
160	stmiage	ip!, {r2-r3}
161	stmiage	ip!, {r2-r3}
162	stmiage	ip!, {r2-r3}
163	stmiage	ip!, {r2-r3}
164	stmiage	ip!, {r2-r3}
165	stmiage	ip!, {r2-r3}
166	stmiage	ip!, {r2-r3}
167	stmiage	ip!, {r2-r3}
168#endif
169	bgt	.Lmemset_loop128
170	it	eq
171	RETeq			/* Zero length so just exit */
172
173	add	r1, r1, #0x80		/* Adjust for extra sub */
174
175	/* Do 32 bytes at a time */
176.Lmemset_loop32:
177	subs	r1, r1, #0x20
178	itttt	ge
179#ifdef _ARM_ARCH_5E
180	strdge	r2, [ip], #0x08
181	strdge	r2, [ip], #0x08
182	strdge	r2, [ip], #0x08
183	strdge	r2, [ip], #0x08
184#else
185	stmiage	ip!, {r2-r3}
186	stmiage	ip!, {r2-r3}
187	stmiage	ip!, {r2-r3}
188	stmiage	ip!, {r2-r3}
189#endif
190	bgt	.Lmemset_loop32
191	it	eq
192	RETeq			/* Zero length so just exit */
193
194	adds	r1, r1, #0x10		/* Partially adjust for extra sub */
195
196	/* Deal with 16 bytes or more */
197	itt	ge
198#ifdef _ARM_ARCH_5E
199	strdge	r2, [ip], #0x08
200	strdge	r2, [ip], #0x08
201#else
202	stmiage	ip!, {r2-r3}
203	stmiage	ip!, {r2-r3}
204#endif
205	it	eq
206	RETeq			/* Zero length so just exit */
207
208	it	lt
209	addlt	r1, r1, #0x10		/* Possibly adjust for extra sub */
210
211	/* We have at least 4 bytes so copy as words */
212.Lmemset_loop4:
213	subs	r1, r1, #0x04
214	it	ge
215	strge	r3, [ip], #0x04
216	bgt	.Lmemset_loop4
217	it	eq
218	RETeq			/* Zero length so just exit */
219
220#ifdef _ARM_ARCH_5E
221	/* Compensate for 64-bit alignment check */
222	adds	r1, r1, #0x04
223	it	eq
224	RETeq
225	cmp	r1, #2
226#else
227	cmp	r1, #-2
228#endif
229
230	strb	r3, [ip], #0x01		/* Set 1 byte */
231	it	ge
232	strbge	r3, [ip], #0x01		/* Set another byte */
233	it	gt
234	strbgt	r3, [ip]		/* and a third */
235	RET			/* Exit */
236
237.Lmemset_wordunaligned:
238	rsb	r2, r2, #0x004
239	strb	r3, [ip], #0x01		/* Set 1 byte */
240	cmp	r2, #0x02
241	it	ge
242	strbge	r3, [ip], #0x01		/* Set another byte */
243	sub	r1, r1, r2
244	it	gt
245	strbgt	r3, [ip], #0x01		/* and a third */
246	cmp	r1, #0x04		/* More than 4 bytes left? */
247	it	ge
248	bge	.Lmemset_wordaligned	/* Yup */
249
250.Lmemset_lessthanfour:
251	cmp	r1, #0x00
252	it	eq
253	RETeq			/* Zero length so exit */
254	strb	r3, [ip], #0x01		/* Set 1 byte */
255	cmp	r1, #0x02
256	it	ge
257	strbge	r3, [ip], #0x01		/* Set another byte */
258	it	gt
259	strbgt	r3, [ip]		/* and a third */
260	RET			/* Exit */
261#ifdef _BZERO
262END(bzero)
263#else
264END(memset)
265#endif
266
267	.section .note.GNU-stack,"",%progbits
268