xref: /minix/common/lib/libc/arch/m68k/string/memset.S (revision 84d9c625)
1/*	$NetBSD: memset.S,v 1.7 2013/09/07 19:06:29 chs Exp $	*/
2
3/*-
4 * Copyright (c) 1997 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by J.T. Conklin.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32/*-
33 * Copyright (c) 1990 The Regents of the University of California.
34 * All rights reserved.
35 *
36 * This code is derived from software contributed to Berkeley by
37 * the Systems Programming Group of the University of Utah Computer
38 * Science Department.
39 *
40 * Redistribution and use in source and binary forms, with or without
41 * modification, are permitted provided that the following conditions
42 * are met:
43 * 1. Redistributions of source code must retain the above copyright
44 *    notice, this list of conditions and the following disclaimer.
45 * 2. Redistributions in binary form must reproduce the above copyright
46 *    notice, this list of conditions and the following disclaimer in the
47 *    documentation and/or other materials provided with the distribution.
48 * 3. Neither the name of the University nor the names of its contributors
49 *    may be used to endorse or promote products derived from this software
50 *    without specific prior written permission.
51 *
52 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
53 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
54 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
55 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
56 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
57 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
62 * SUCH DAMAGE.
63 */
64
65#include <machine/asm.h>
66
67#if defined(LIBC_SCCS) && !defined(lint)
68#if 0
69	RCSID("from: @(#)bzero.s	5.1 (Berkeley) 5/12/90")
70#else
71	RCSID("$NetBSD: memset.S,v 1.7 2013/09/07 19:06:29 chs Exp $")
72#endif
73#endif /* LIBC_SCCS and not lint */
74
75ENTRY(memset)
76	movl	%d2,-(%sp)
77	movl	8(%sp),%a0		| destination
78	movl	16(%sp),%d1		| count
79	movb	15(%sp),%d2		| get fill character
80
81	/*
82	 * It isn't worth the overhead of aligning to {long}word boundries
83	 * if the string is too short.
84	 */
85	cmpl	#15,%d1
86	jlt	.Lbzbyte
87
88	clrl %d0
89	moveb	%d2,%d0
90	movel	%d0,%d2
91	lsll	#8,%d0
92	orl	%d0,%d2
93	lsll	#8,%d0
94	orl	%d0,%d2
95	lsll	#8,%d0
96	orl	%d0,%d2
97
98	/* word align */
99	movl	%a0,%d0
100	btst	#0,%d0			| if (dst & 1)
101	jeq	.Lbzalgndw		|
102	movb	%d2,(%a0)+		|	*(char *)dst++ = X
103	subql	#1,%d1			|	len--
104	addql	#1,%d0
105.Lbzalgndw:
106#ifndef	__mc68010__
107	/* long word align */
108	btst	#1,%d0			| if (dst & 2)
109	jeq	.Lbzalgndl		|
110	movw	%d2,(%a0)+		|	*(short *)dst++ = X
111	subql	#2,%d1			|	len -= 2
112.Lbzalgndl:
113	/* set by 8 longwords */
114	movel	%d1,%d0
115	lsrl	#5,%d0			| cnt = len / 32
116	jeq	.Lbzlong			| if (cnt)
117	andl	#31,%d1			|	len %= 32
118	subql	#1,%d0			|	set up for dbf
119.Lbz32loop:
120	movl	%d2,(%a0)+		|	set 8 long words
121	movl	%d2,(%a0)+
122	movl	%d2,(%a0)+
123	movl	%d2,(%a0)+
124	movl	%d2,(%a0)+
125	movl	%d2,(%a0)+
126	movl	%d2,(%a0)+
127	movl	%d2,(%a0)+
128#ifndef __mcoldfire__
129	dbf	%d0,.Lbz32loop		|	till done
130	clrw	%d0
131#endif
132	subql	#1,%d0
133	jcc	.Lbz32loop
134#endif	/* !__mc68010__ */
135
136.Lbzlong:
137	/* set by longwords */
138	movel	%d1,%d0
139	lsrl	#2,%d0			| cnt = len / 4
140	jeq	.Lbzbyte			| if (cnt)
141	subql	#1,%d0			|	set up for dbf
142.Lbzlloop:
143	movl	%d2,(%a0)+		|	clear longwords
144#ifndef __mcoldfire__
145	dbf	%d0,.Lbzlloop		|	till done
146#endif
147#ifdef	__mc68010__
148	clrw	%d0
149#endif	/* __mc68010__ */
150#if defined(__m68010) || defined(__mcoldfire__)
151	subql	#1,%d0
152	jcc	.Lbzlloop
153#endif	/* __mc68010__ || __mcoldfire__ */
154	andl	#3,%d1			|	len %= 4
155	jeq	.Lbzdone
156
157	subql	#1,%d1			| set up for dbf
158.Lbzbloop:
159	movb	%d2,(%a0)+		| set bytes
160.Lbzbyte:
161#ifdef __mcoldfire__
162	subql	#1,%d1			| decrement
163	jcc	.Lbzbloop		| till done
164#else
165	dbf	%d1,.Lbzbloop		| till done
166#endif
167.Lbzdone:
168	movl	8(%sp),%d0		| return destination
169#ifdef __SVR4_ABI__
170	moveal	%d0,%a0
171#endif
172	movl	(%sp)+,%d2
173	rts
174END(memset)
175