xref: /netbsd-src/sys/lib/libkern/arch/vax/blkcpy.S (revision 95e1ffb15694e54f29f8baaa4232152b703c2a5a)
1/*	$NetBSD: blkcpy.S,v 1.4 2005/12/11 12:24:45 christos Exp $	*/
2/*
3 * Copyright (c) 1983, 1993
4 *	The Regents of the University of California.  All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of the University nor the names of its contributors
15 *    may be used to endorse or promote products derived from this software
16 *    without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30#include <machine/asm.h>
31
32/* __blkcpy(from, to, size) */
33
34ENTRY(__blkcpy, R6)
35	movl	4(%ap),%r1
36	movl	8(%ap),%r3
37	movl	12(%ap),%r6
38	cmpl	%r1,%r3
39	bgtr	2f		# normal forward case
40	blss	3f		# overlapping, must do backwards
41	ret			# equal, nothing to do
421:
43	subl2	%r0,%r6
44	movc3	%r0,(%r1),(%r3)
452:
46	movzwl	$65535,%r0
47	cmpl	%r6,%r0
48	jgtr	1b
49	movc3	%r6,(%r1),(%r3)
50	ret
513:
52	addl2	%r6,%r1
53	addl2	%r6,%r3
54	movzwl	$65535,%r0
55	jbr	5f
564:
57	subl2	%r0,%r6
58	subl2	%r0,%r1
59	subl2	%r0,%r3
60	movc3	%r0,(%r1),(%r3)
61	movzwl	$65535,%r0
62	subl2	%r0,%r1
63	subl2	%r0,%r3
645:
65	cmpl	%r6,%r0
66	jgtr	4b
67	subl2	%r6,%r1
68	subl2	%r6,%r3
69	movc3	%r6,(%r1),(%r3)
70	ret
71