xref: /netbsd-src/common/lib/libc/arch/m68k/string/bcopy.S (revision d48f14661dda8638fee055ba15d35bdfb29b9fa8)
1/*	$NetBSD: bcopy.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: @(#)bcopy.s	5.1 (Berkeley) 5/12/90")
77#else
78	RCSID("$NetBSD: bcopy.S,v 1.1 2005/12/20 19:28:49 christos Exp $")
79#endif
80#endif /* LIBC_SCCS and not lint */
81
82
83#ifdef MEMCOPY
84ENTRY(memcpy)
85#else
86#ifdef MEMMOVE
87ENTRY(memmove)
88#else
89ENTRY(bcopy)
90#endif
91#endif
92#if defined(MEMCOPY) || defined(MEMMOVE)
93	movl	%sp@(4),%a1		| dest address
94	movl	%sp@(8),%a0		| src address
95#else
96	movl	%sp@(4),%a0		| src address
97	movl	%sp@(8),%a1		| dest address
98#endif
99	movl	%sp@(12),%d1		| count
100
101	cmpl	%a1,%a0			| src after dest?
102	jlt	Lbcback			| yes, must copy backwards
103
104	/*
105	 * It isn't worth the overhead of aligning to {long}word boundries
106	 * if the string is too short.
107	 */
108	cmpl	#8,%d1
109	jlt	Lbcfbyte
110
111#ifdef	__mc68010__
112	/*
113	 * The 68010 cannot access a word or long on an odd boundary,
114	 * period.  If the source and the destination addresses aren't
115	 * of the same evenness, we're forced to do a bytewise copy.
116	 */
117	movl	%a0,%d0
118	addl	%a1,%d0
119	btst	#0,%d0
120	jne	Lbcfbyte
121#endif	/* __mc68010__ */
122
123	/* word align */
124	movl	%a1,%d0
125	btst	#0,%d0		| if (dst & 1)
126	jeq	Lbcfalgndw	|
127	movb	%a0@+,%a1@+	|	*(char *)dst++ = *(char *) src++
128	subql	#1,%d1		|	len--
129Lbcfalgndw:
130	/* long word align */
131	btst	#1,%d0		| if (dst & 2)
132	jeq	Lbcfalgndl
133	movw	%a0@+,%a1@+	|	*(short *)dst++ = *(short *) dst++
134	subql	#2,%d1		|	len -= 2
135Lbcfalgndl:
136	/* copy by 8 longwords */
137	movel	%d1,%d0
138	lsrl	#5,%d0		| cnt = len / 32
139	jeq	Lbcflong	| if (cnt)
140	andl	#31,%d1		|	len %= 32
141	subql	#1,%d0		|	set up for dbf
142Lbcf32loop:
143	movl	%a0@+,%a1@+	|	copy 8 long words
144	movl	%a0@+,%a1@+
145	movl	%a0@+,%a1@+
146	movl	%a0@+,%a1@+
147	movl	%a0@+,%a1@+
148	movl	%a0@+,%a1@+
149	movl	%a0@+,%a1@+
150	movl	%a0@+,%a1@+
151	dbf	%d0,Lbcf32loop	|	till done
152	clrw	%d0
153	subql	#1,%d0
154	jcc	Lbcf32loop
155
156Lbcflong:
157	/* copy by longwords */
158	movel	%d1,%d0
159	lsrl	#2,%d0		| cnt = len / 4
160	jeq	Lbcfbyte	| if (cnt)
161	subql	#1,%d0		|	set up for dbf
162Lbcflloop:
163	movl	%a0@+,%a1@+	|	copy longwords
164	dbf	%d0,Lbcflloop	|	til done
165	andl	#3,%d1		|	len %= 4
166	jeq	Lbcdone
167
168	subql	#1,%d1		| set up for dbf
169Lbcfbloop:
170	movb	%a0@+,%a1@+	| copy bytes
171Lbcfbyte:
172	dbf	%d1,Lbcfbloop	| till done
173Lbcdone:
174#if defined(MEMCOPY) || defined(MEMMOVE)
175	movl	%sp@(4),%d0	| dest address
176#if defined(__SVR4_ABI__)
177	moveal	%d0,%a0
178#endif
179#endif
180	rts
181
182
183Lbcback:
184	addl	%d1,%a0		| src pointer to end
185	addl	%d1,%a1		| dest pointer to end
186
187	/*
188	 * It isn't worth the overhead of aligning to {long}word boundries
189	 * if the string is too short.
190	 */
191	cmpl	#8,%d1
192	jlt	Lbcbbyte
193
194#ifdef	__mc68010__
195	/*
196	 * The 68010 cannot access a word or long on an odd boundary,
197	 * period.  If the source and the destination addresses aren't
198	 * of the same evenness, we're forced to do a bytewise copy.
199	 */
200	movl	%a0,%d0
201	addl	%a1,%d0
202	btst	#0,%d0
203	jne	Lbcbbyte
204#endif	/* __mc68010__ */
205
206	/* word align */
207	movl	%a1,%d0
208	btst	#0,%d0		| if (dst & 1)
209	jeq	Lbcbalgndw	|
210	movb	%a0@-,%a1@-	|	*(char *)dst-- = *(char *) src--
211	subql	#1,%d1		|	len--
212Lbcbalgndw:
213	/* long word align */
214	btst	#1,%d0		| if (dst & 2)
215	jeq	Lbcbalgndl
216	movw	%a0@-,%a1@-	|	*(short *)dst-- = *(short *) dst--
217	subql	#2,%d1		|	len -= 2
218Lbcbalgndl:
219	/* copy by 8 longwords */
220	movel	%d1,%d0
221	lsrl	#5,%d0		| cnt = len / 32
222	jeq	Lbcblong	| if (cnt)
223	andl	#31,%d1		|	len %= 32
224	subql	#1,%d0		|	set up for dbf
225Lbcb32loop:
226	movl	%a0@-,%a1@-	|	copy 8 long words
227	movl	%a0@-,%a1@-
228	movl	%a0@-,%a1@-
229	movl	%a0@-,%a1@-
230	movl	%a0@-,%a1@-
231	movl	%a0@-,%a1@-
232	movl	%a0@-,%a1@-
233	movl	%a0@-,%a1@-
234	dbf	%d0,Lbcb32loop	|	till done
235	clrw	%d0
236	subql	#1,%d0
237	jcc	Lbcb32loop
238
239Lbcblong:
240	/* copy by longwords */
241	movel	%d1,%d0
242	lsrl	#2,%d0		| cnt = len / 4
243	jeq	Lbcbbyte	| if (cnt)
244	subql	#1,%d0		|	set up for dbf
245Lbcblloop:
246	movl	%a0@-,%a1@-	|	copy longwords
247	dbf	%d0,Lbcblloop	|	til done
248	andl	#3,%d1		|	len %= 4
249	jeq	Lbcdone
250
251	subql	#1,%d1		| set up for dbf
252Lbcbbloop:
253	movb	%a0@-,%a1@-	| copy bytes
254Lbcbbyte:
255	dbf	%d1,Lbcbbloop	| till done
256
257#if defined(MEMCOPY) || defined(MEMMOVE)
258	movl	%sp@(4),%d0	| dest address
259#if defined(__SVR4_ABI__)
260	moveal	%d0,%a0
261#endif
262#endif
263	rts
264