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/* ffs -- find first set bit in a word, counted from least significant end.
For IBM rs6000.
Copyright (C) 1991, 1992 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., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#include <ansidecl.h>
#include <string.h>
#undef ffs
#ifdef __GNUC__
int
DEFUN(ffs, (x), int x)
{
int cnt;
asm ("cntlz %0,%1" : "=r" (cnt) : "r" (x & -x));
return 32 - cnt;
}
#else
#include <sysdeps/generic/ffs.c>
#endif
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