xref: /netbsd-src/external/gpl3/gcc.old/dist/libgcc/config/lm32/_mulsi3.c (revision 8feb0f0b7eaff0608f8350bbfa3098827b4bb91b)
136ac495dSmrg /* _mulsi3 for Lattice Mico32.
236ac495dSmrg    Contributed by Jon Beniston <jon@beniston.com>
336ac495dSmrg 
4*8feb0f0bSmrg    Copyright (C) 2009-2020 Free Software Foundation, Inc.
536ac495dSmrg 
636ac495dSmrg    This file is free software; you can redistribute it and/or modify it
736ac495dSmrg    under the terms of the GNU General Public License as published by the
836ac495dSmrg    Free Software Foundation; either version 3, or (at your option) any
936ac495dSmrg    later version.
1036ac495dSmrg 
1136ac495dSmrg    This file is distributed in the hope that it will be useful, but
1236ac495dSmrg    WITHOUT ANY WARRANTY; without even the implied warranty of
1336ac495dSmrg    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
1436ac495dSmrg    General Public License for more details.
1536ac495dSmrg 
1636ac495dSmrg    Under Section 7 of GPL version 3, you are granted additional
1736ac495dSmrg    permissions described in the GCC Runtime Library Exception, version
1836ac495dSmrg    3.1, as published by the Free Software Foundation.
1936ac495dSmrg 
2036ac495dSmrg    You should have received a copy of the GNU General Public License and
2136ac495dSmrg    a copy of the GCC Runtime Library Exception along with this program;
2236ac495dSmrg    see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
2336ac495dSmrg    <http://www.gnu.org/licenses/>. */
2436ac495dSmrg 
2536ac495dSmrg #include "libgcc_lm32.h"
2636ac495dSmrg 
2736ac495dSmrg /* Integer multiplication.  */
2836ac495dSmrg 
2936ac495dSmrg USItype
__mulsi3(USItype a,USItype b)3036ac495dSmrg __mulsi3 (USItype a, USItype b)
3136ac495dSmrg {
3236ac495dSmrg   USItype result;
3336ac495dSmrg 
3436ac495dSmrg   result = 0;
3536ac495dSmrg 
3636ac495dSmrg   if (a == 0)
3736ac495dSmrg     return 0;
3836ac495dSmrg 
3936ac495dSmrg   while (b != 0)
4036ac495dSmrg     {
4136ac495dSmrg       if (b & 1)
4236ac495dSmrg 	result += a;
4336ac495dSmrg       a <<= 1;
4436ac495dSmrg       b >>= 1;
4536ac495dSmrg     }
4636ac495dSmrg 
4736ac495dSmrg   return result;
4836ac495dSmrg }
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