/* 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, 2004 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 Lesser General Public License as published by the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ #define ffsl __something_else #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) libc_hidden_builtin_def (ffs) #undef ffsl weak_alias (__ffs, ffsl) #else #include <sysdeps/generic/ffs.c> #endif