sysdeps/generic/ffsll.c

   1 /* Copyright (C) 1991, 1992, 1997, 1998 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Torbjorn Granlund (tege@sics.se).
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <limits.h>
  21 #define ffsl __something_else
  22 #include <string.h>
  23
  24 #undef  ffsll
  25
  26 /* Find the first bit set in I.  */
  27 int
  28 ffsll (i)
  29      long long int i;
  30 {
  31   unsigned long long int x = i & -i;
  32
  33   if (x <= 0xffffffff)
  34     return ffs (i);
  35   else
  36     return 32 + ffs (i >> 32);
  37 }
  38
  39 #if ULONG_MAX != UINT_MAX
  40 #undef ffsl
  41 weak_alias (ffsll, ffsl)
  42 #endif