xref: /netbsd-src/common/lib/libc/arch/m68k/string/memset.S (revision e5548b402ae4c44fb816de42c7bba9581ce23ef5)
1/*	$NetBSD: memset.S,v 1.1 2005/12/20 19:28:49 christos 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 * 3. All advertising materials mentioning features or use of this software
19 *    must display the following acknowledgement:
20 *        This product includes software developed by the NetBSD
21 *        Foundation, Inc. and its contributors.
22 * 4. Neither the name of The NetBSD Foundation nor the names of its
23 *    contributors may be used to endorse or promote products derived
24 *    from this software without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 * POSSIBILITY OF SUCH DAMAGE.
37 */
38
39/*-
40 * Copyright (c) 1990 The Regents of the University of California.
41 * All rights reserved.
42 *
43 * This code is derived from software contributed to Berkeley by
44 * the Systems Programming Group of the University of Utah Computer
45 * Science Department.
46 *
47 * Redistribution and use in source and binary forms, with or without
48 * modification, are permitted provided that the following conditions
49 * are met:
50 * 1. Redistributions of source code must retain the above copyright
51 *    notice, this list of conditions and the following disclaimer.
52 * 2. Redistributions in binary form must reproduce the above copyright
53 *    notice, this list of conditions and the following disclaimer in the
54 *    documentation and/or other materials provided with the distribution.
55 * 3. Neither the name of the University nor the names of its contributors
56 *    may be used to endorse or promote products derived from this software
57 *    without specific prior written permission.
58 *
59 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
60 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
61 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
62 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
63 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
64 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
65 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
66 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
67 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
68 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
69 * SUCH DAMAGE.
70 */
71
72#include <machine/asm.h>
73
74#if defined(LIBC_SCCS) && !defined(lint)
75#if 0
76	RCSID("from: @(#)bzero.s	5.1 (Berkeley) 5/12/90")
77#else
78	RCSID("$NetBSD: memset.S,v 1.1 2005/12/20 19:28:49 christos Exp $")
79#endif
80#endif /* LIBC_SCCS and not lint */
81
82ENTRY(memset)
83	movl	%d2,%sp@-
84	movl	%sp@(8),%a0		| destination
85	movl	%sp@(16),%d1		| count
86	movb	%sp@(15),%d2		| character
87
88	/*
89	 * It isn't worth the overhead of aligning to {long}word boundries
90	 * if the string is too short.
91	 */
92	cmpl	#15,%d1
93	jlt	Lbzbyte
94
95	clrl	%d0			| replicate byte to fill longword
96	movb	%d2,%d0
97	movl	%d0,%d2
98	lsll	#8,%d0
99	orl	%d0,%d2
100	lsll	#8,%d0
101	orl	%d0,%d2
102	lsll	#8,%d0
103	orl	%d0,%d2
104
105	/* word align */
106	movl	%a0,%d0
107	btst	#0,%d0			| if (dst & 1)
108	jeq	Lbzalgndw		|
109	movb	%d2,%a0@+		|	*(char *)dst++ = X
110	subql	#1,%d1			|	len--
111	addql	#1,%d0
112Lbzalgndw:
113#ifndef	__mc68010__
114	/* long word align */
115	btst	#1,%d0			| if (dst & 2)
116	jeq	Lbzalgndl		|
117	movw	%d2,%a0@+		|	*(short *)dst++ = X
118	subql	#2,%d1			|	len -= 2
119Lbzalgndl:
120	/* set by 8 longwords */
121	movel	%d1,%d0
122	lsrl	#5,%d0			| cnt = len / 32
123	jeq	Lbzlong			| if (cnt)
124	andl	#31,%d1			|	len %= 32
125	subql	#1,%d0			|	set up for dbf
126Lbz32loop:
127	movl	%d2,%a0@+		|	set 8 long words
128	movl	%d2,%a0@+
129	movl	%d2,%a0@+
130	movl	%d2,%a0@+
131	movl	%d2,%a0@+
132	movl	%d2,%a0@+
133	movl	%d2,%a0@+
134	movl	%d2,%a0@+
135	dbf	%d0,Lbz32loop		|	till done
136	clrw	%d0
137	subql	#1,%d0
138	jcc	Lbz32loop
139#endif	/* !__mc68010__ */
140
141Lbzlong:
142	/* set by longwords */
143	movel	%d1,%d0
144	lsrl	#2,%d0			| cnt = len / 4
145	jeq	Lbzbyte			| if (cnt)
146	subql	#1,%d0			|	set up for dbf
147Lbzlloop:
148	movl	%d2,%a0@+		|	clear longwords
149	dbf	%d0,Lbzlloop		|	till done
150#ifdef	__mc68010__
151	clrw	%d0
152	subql	#1,%d0
153	jcc	Lbzlloop
154#endif	/* __mc68010__ */
155	andl	#3,%d1			|	len %= 4
156	jeq	Lbzdone
157
158	subql	#1,%d1			| set up for dbf
159Lbzbloop:
160	movb	%d2,%a0@+		| set bytes
161Lbzbyte:
162	dbf	%d1,Lbzbloop		| till done
163Lbzdone:
164	movl	%sp@(8),%d0		| return destination
165#ifdef __SVR4_ABI__
166	moveal	%d0,%a0
167#endif
168	movl	%sp@+,%d2
169	rts
170