1 /* ffs -- find first set bit in a word, counted from least significant end.
3 This file is part of the GNU C Library.
4 Copyright (C) 1991, 92, 93, 94, 97, 98 Free Software Foundation, Inc.
5 Contributed by Torbjorn Granlund (tege@sics.se).
7 The GNU C Library is free software; you can redistribute it and/or
8 modify it under the terms of the GNU Lesser General Public
9 License as published by the Free Software Foundation; either
10 version 2.1 of the License, or (at your option) any later version.
12 The GNU C Library is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 Lesser General Public License for more details.
17 You should have received a copy of the GNU Lesser General Public
18 License along with the GNU C Library; if not, write to the Free
19 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
22 #define ffsl __something_else
36 asm ("xorl %0,%0\n" /* Set CNT to zero. */
37 "bsfl %2,%1\n" /* Count low bits in X and store in %1. */
38 "jz 1f\n" /* Jump if OK, i.e. X was non-zero. */
39 "leal 1(%1),%0\n" /* Return bsfl-result plus one on %0. */
40 "1:" : "=&a" (cnt
), "=r" (tmp
) : "rm" (x
));
44 weak_alias (__ffs
, ffs
)
46 weak_alias (__ffs
, ffsl
)
49 #include <sysdeps/generic/ffs.c>