mult.c
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/*
* This file is part of GNU CC.
*
* GNU CC is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published
* by the Free Software Foundation; either version 2, or (at your
* option) any later version.
*
* GNU CC is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with GNU CC; see the file COPYING. If not, write
* to the Free Software Foundation, 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include <common.h>
#if !defined(CFG_NIOS_MULT_HW) && !defined(CFG_NIOS_MULT_MSTEP)
#include "math.h"
USItype __mulsi3 (USItype a, USItype b)
{
USItype c = 0;
while (a != 0) {
if (a & 1)
c += b;
a >>= 1;
b <<= 1;
}
return c;
}
UHItype __mulhi3 (UHItype a, UHItype b)
{
UHItype c = 0;
while (a != 0) {
if (a & 1)
c += b;
a >>= 1;
b <<= 1;
}
return c;
}
#endif /*!defined(CFG_NIOS_MULT_HW) && !defined(CFG_NIOS_MULT_MSTEP) */