48 lines
1.3 KiB
C
48 lines
1.3 KiB
C
/* 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 Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 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
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; 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
|