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/* ffs -- find first set bit in a word, counted from least significant end.
   For Intel 80x86, x>=3.
   This file is part of the GNU C Library.
   Copyright (C) 1991, 1992, 1993, 1994, 1997 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>

#undef	ffs

#ifdef	__GNUC__

int
ffs (x)
     int x;
{
  int cnt;
  int tmp;

  asm ("xorl %0,%0\n"		/* Set CNT to zero.  */
       "bsfl %2,%1\n"		/* Count low bits in X and store in %1.  */
       "jz 1f\n"		/* Jump if OK, i.e. X was non-zero.  */
       "leal 1(%1),%0\n"	/* Return bsfl-result plus one on %0.  */
       "1:" : "=&a" (cnt), "=r" (tmp) : "rm" (x));

  return cnt;
}

#else
#include <sysdeps/generic/ffs.c>
#endif