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/* ffs -- find first set bit in a word, counted from least significant end.
For Intel 80x86, x>=6.
This file is part of the GNU C Library.
Copyright (C) 1991, 92, 93, 94, 97, 98 Free Software Foundation, Inc.
Contributed by Ulrich Drepper <drepper@cygnus.com>.
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 ("bsfl %2,%0\n" /* Count low bits in X and store in %1. */
"cmovel %1,%0\n" /* If number was zero, use -1 as result. */
: "=&r" (cnt), "=r" (tmp) : "rm" (x), "1" (-1));
return cnt + 1;
}
weak_alias (__ffs, ffs)
#else
#include <sysdeps/generic/ffs.c>
#endif
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