gold/ffsll.c

   1 /* ffsll.c -- version of ffsll for gold.  */
   2
   3 /* Copyright 2009 Free Software Foundation, Inc.
   4    Written by Ian Lance Taylor <iant@google.com>.
   5
   6    This file is part of gold.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21    MA 02110-1301, USA.  */
  22
  23 #include "config.h"
  24
  25 #include <string.h>
  26
  27 extern int ffsll (long long);
  28
  29 /* This file implements ffsll for systems which don't have it.  We use
  30    ffsll if possible because gcc supports it as a builtin which will
  31    use a machine instruction if there is one.  */
  32
  33 int
  34 ffsll (long long arg)
  35 {
  36   unsigned long long i;
  37   int ret;
  38
  39   if (arg == 0)
  40     ret = 0;
  41   else
  42     {
  43       ret = 1;
  44       for (i = (unsigned long long) arg; (i & 1) == 0; i >>= 1)
  45         ++ret;
  46     }
  47   return ret;
  48 }