xref: /netbsd-src/sys/arch/amiga/stand/bootblock/boot/muldi3.s (revision dc306354b0b29af51801a7632f1e95265a68cd81)
1/*	$NetBSD: muldi3.s,v 1.1.1.1 1996/11/29 23:36:30 is Exp $
2 *
3 * Copyright (c) 1996 Ignatios Souvatzis
4 * 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. All advertising materials mentioning features or use of this software
15 *    must display the following acknowledgement:
16 *      This product includes software developed by Ignatios Souvatzis
17 *      for the NetBSD project.
18 * 4. The name of the author may not be used to endorse or promote products
19 *    derived from this software without specific prior written permission
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 *
32 * Slow but small muldi3.
33 * Beware... the multiplicand is unsigned (but should be enough for
34 * usage by ufs.c :-)
35 */
36
37	.text
38	.even
39	.globl	___muldi3
40___muldi3:
41	movml d2/d3/d4/d5/d6,sp@-	| 0..4 regs, 5 pc, 6..9 parameters
42	movml sp@(24),d2-d5
43|	movl sp@(24),d2
44|	movl sp@(28),d3
45|	movl sp@(32),d4
46|	movl sp@(36),d5
47	movq #0,d0
48	movq #0,d1
49	movq #63,d6
50L4:
51	asrl #1,d2
52	roxrl #1,d3
53	jcc L5
54	addl d5,d1
55	addxl d4,d0
56L5:
57	addl d5,d5
58	addxl d4,d4
59L7:
60	dbra d6,L4
61	movml sp@+,d2/d3/d4/d5/d6
62	rts
63