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glibc  2.9
ffsll.c
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00001 /* Copyright (C) 1991, 1992, 1997, 1998 Free Software Foundation, Inc.
00002    This file is part of the GNU C Library.
00003    Contributed by Torbjorn Granlund (tege@sics.se).
00004 
00005    The GNU C Library is free software; you can redistribute it and/or
00006    modify it under the terms of the GNU Lesser General Public
00007    License as published by the Free Software Foundation; either
00008    version 2.1 of the License, or (at your option) any later version.
00009 
00010    The GNU C Library is distributed in the hope that it will be useful,
00011    but WITHOUT ANY WARRANTY; without even the implied warranty of
00012    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00013    Lesser General Public License for more details.
00014 
00015    You should have received a copy of the GNU Lesser General Public
00016    License along with the GNU C Library; if not, write to the Free
00017    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00018    02111-1307 USA.  */
00019 
00020 #include <limits.h>
00021 #define ffsl __something_else
00022 #include <string.h>
00023 
00024 #undef ffsll
00025 
00026 /* Find the first bit set in I.  */
00027 int
00028 ffsll (i)
00029      long long int i;
00030 {
00031   unsigned long long int x = i & -i;
00032 
00033   if (x <= 0xffffffff)
00034     return ffs (i);
00035   else
00036     return 32 + ffs (i >> 32);
00037 }
00038 
00039 #if ULONG_MAX != UINT_MAX
00040 #undef ffsl
00041 weak_alias (ffsll, ffsl)
00042 #endif