xref: /minix/common/lib/libc/arch/powerpc/string/ffs.S (revision ebfedea0)
1/*	$NetBSD: ffs.S,v 1.5 2011/01/15 07:31:12 matt Exp $ */
2
3/*-
4 * Copyright (C) 2001	Martin J. Laubach <mjl@NetBSD.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. The name of the author may not be used to endorse or promote products
16 *    derived from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29/*----------------------------------------------------------------------*/
30
31#include <machine/asm.h>
32
33__RCSID("$NetBSD: ffs.S,v 1.5 2011/01/15 07:31:12 matt Exp $")
34
35	.align 4
36ENTRY(ffs)
37	neg	%r4, %r3
38	and	%r3, %r4, %r3
39	cntlzw	%r3, %r3
40	li	%r0, 32
41	subf	%r3, %r3, %r0
42	blr
43END(ffs)
44
45/*----------------------------------------------------------------------*/
46