glibc/sysdeps/powerpc/ffs.c

33 lines
1.1 KiB
C

/* Find first set bit in a word, counted from least significant end.
For PowerPC.
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. */
#include <string.h>
int
__ffs (int x)
{
int cnt;
asm ("cntlzw %0,%1" : "=r" (cnt) : "r" (x & -x));
return 32 - cnt;
}
weak_alias (__ffs, ffs)
weak_alais (__ffs, ffsl)