gcc/libgcc/config/nios2/lib2-divmod.c

118 lines
2.0 KiB
C

/* Copyright (C) 2012-2015 Free Software Foundation, Inc.
Contributed by Altera and Mentor Graphics, Inc.
This file 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.
This file 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/>. */
#include "lib2-nios2.h"
/* 32-bit SI divide and modulo as used in Nios II. */
static USItype
udivmodsi4 (USItype num, USItype den, word_type modwanted)
{
USItype bit = 1;
USItype res = 0;
while (den < num && bit && !(den & (1L<<31)))
{
den <<=1;
bit <<=1;
}
while (bit)
{
if (num >= den)
{
num -= den;
res |= bit;
}
bit >>=1;
den >>=1;
}
if (modwanted)
return num;
return res;
}
SItype
__divsi3 (SItype a, SItype b)
{
word_type neg = 0;
SItype res;
if (a < 0)
{
a = -a;
neg = !neg;
}
if (b < 0)
{
b = -b;
neg = !neg;
}
res = udivmodsi4 (a, b, 0);
if (neg)
res = -res;
return res;
}
SItype
__modsi3 (SItype a, SItype b)
{
word_type neg = 0;
SItype res;
if (a < 0)
{
a = -a;
neg = 1;
}
if (b < 0)
b = -b;
res = udivmodsi4 (a, b, 1);
if (neg)
res = -res;
return res;
}
SItype
__udivsi3 (SItype a, SItype b)
{
return udivmodsi4 (a, b, 0);
}
SItype
__umodsi3 (SItype a, SItype b)
{
return udivmodsi4 (a, b, 1);
}