Retro68/gcc/libgcc/config/cr16/divmodhi3.c
2015-08-28 17:33:40 +02:00

116 lines
2.2 KiB
C

/* Libgcc Target specific implementation - Emulating div and mod.
Copyright (C) 2012-2015 Free Software Foundation, Inc.
Contributed by KPIT Cummins Infosystems Limited.
This file is part of GCC.
GCC 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 3, or (at your option)
any later version.
GCC 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.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
/* Emulate the division and modulus operation. */
unsigned short
udivmodhi4 (unsigned short num, unsigned short den, short modwanted)
{
unsigned short bit = 1;
unsigned short res = 0;
while (den < num && bit && !(den & (1 << 15)))
{
den <<= 1;
bit <<= 1;
}
while (bit)
{
if (num >= den)
{
num -= den;
res |= bit;
}
bit >>= 1;
den >>= 1;
}
if (modwanted)
return num;
return res;
}
short
__divhi3 (short a, short b)
{
short neg = 0;
short res;
if (a < 0)
{
a = -a;
neg = !neg;
}
if (b < 0)
{
b = -b;
neg = !neg;
}
res = udivmodhi4 (a, b, 0);
if (neg)
res = -res;
return res;
}
short
__modhi3 (short a, short b)
{
short neg = 0;
short res;
if (a < 0)
{
a = -a;
neg = 1;
}
if (b < 0)
b = -b;
res = udivmodhi4 (a, b, 1);
if (neg)
res = -res;
return res;
}
short
__udivhi3 (short a, short b)
{
return udivmodhi4 (a, b, 0);
}
short
__umodhi3 (short a, short b)
{
return udivmodhi4 (a, b, 1);
}