mirror of
https://github.com/autc04/Retro68.git
synced 2024-11-28 05:51:04 +00:00
116 lines
2.2 KiB
C
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);
|
|
}
|