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glibc  2.9
ffsll.c
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00001 /* Find first set bit in a word, counted from least significant end.
00002    For PowerPC.
00003    Copyright (C) 1991, 1992, 1997, 1998, 2004 Free Software Foundation, Inc.
00004    This file is part of the GNU C Library.
00005    Contributed by Torbjorn Granlund (tege@sics.se).
00006 
00007    The GNU C Library is free software; you can redistribute it and/or
00008    modify it under the terms of the GNU Lesser General Public
00009    License as published by the Free Software Foundation; either
00010    version 2.1 of the License, or (at your option) any later version.
00011 
00012    The GNU C Library is distributed in the hope that it will be useful,
00013    but WITHOUT ANY WARRANTY; without even the implied warranty of
00014    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015    Lesser General Public License for more details.
00016 
00017    You should have received a copy of the GNU Lesser General Public
00018    License along with the GNU C Library; if not, write to the Free
00019    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00020    02111-1307 USA.  */
00021 
00022 #define ffsl __something_else
00023 #include <limits.h>
00024 #include <string.h>
00025 
00026 #undef ffs
00027 
00028 int
00029 __ffsll (long long int x)
00030 {
00031   int cnt;
00032 
00033   asm ("cntlzd %0,%1" : "=r" (cnt) : "r" (x & -x));
00034   return 64 - cnt;
00035 }
00036 weak_alias (__ffsll, ffsll)
00037 #undef ffsl
00038 weak_alias (__ffsll, ffsl)