summaryrefslogtreecommitdiff
path: root/sysdeps/m68k/ffs.c
blob: bed3f4686619c5f37b0b36e7f7c2df67cd668744 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
/* ffs -- find first set bit in a word, counted from least significant end.
   For mc68020, mc68030, mc68040.
   This file is part of the GNU C Library.
   Copyright (C) 1991, 1992, 1997, 1998 Free Software Foundation, Inc.
   Contributed by Torbjorn Granlund (tege@sics.se).

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#define ffsl __something_else
#include <string.h>

#undef	ffs

#if	defined (__GNUC__) && defined (__mc68020__)

int
__ffs (x)
     int x;
{
  int cnt;

  asm ("bfffo %1{#0:#0},%0" : "=d" (cnt) : "dm" (x & -x));

  return 32 - cnt;
}
weak_alias (__ffs, ffs)
#undef ffsl
weak_alias (__ffs, ffsl)

#else

#include <sysdeps/generic/ffs.c>

#endif