Retro68/gcc/libgcc/config/lm32/_divsi3.c
2014-09-21 19:33:12 +02:00

100 lines
2.9 KiB
C

/* _divsi3 for Lattice Mico32.
Contributed by Jon Beniston <jon@beniston.com>
Copyright (C) 2009-2014 Free Software Foundation, 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 "libgcc_lm32.h"
/* Signed integer division. */
static const UQItype __divsi3_table[] = {
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 2, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 3, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 4, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 5, 2, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 6, 3, 2, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 7, 3, 2, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0,
0, 8, 4, 2, 2, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0,
0, 9, 4, 3, 2, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0,
0, 10, 5, 3, 2, 2, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0,
0, 11, 5, 3, 2, 2, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0,
0, 12, 6, 4, 3, 2, 2, 1, 1, 1, 1, 1, 1, 0, 0, 0,
0, 13, 6, 4, 3, 2, 2, 1, 1, 1, 1, 1, 1, 1, 0, 0,
0, 14, 7, 4, 3, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 0,
0, 15, 7, 5, 3, 3, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1,
};
SItype
__divsi3 (SItype a, SItype b)
{
int neg = 0;
SItype res;
int cfg;
if (b == 0)
{
/* Raise divide by zero exception. */
int eba, sr;
/* Save interrupt enable. */
__asm__ __volatile__ ("rcsr %0, IE":"=r" (sr));
sr = (sr & 1) << 1;
__asm__ __volatile__ ("wcsr IE, %0"::"r" (sr));
/* Branch to exception handler. */
__asm__ __volatile__ ("rcsr %0, EBA":"=r" (eba));
eba += 32 * 5;
__asm__ __volatile__ ("mv ea, ra");
__asm__ __volatile__ ("b %0"::"r" (eba));
__builtin_unreachable ();
}
if (((USItype) (a | b)) < 16)
res = __divsi3_table[(a << 4) + b];
else
{
if (a < 0)
{
a = -a;
neg = !neg;
}
if (b < 0)
{
b = -b;
neg = !neg;
}
__asm__ ("rcsr %0, CFG":"=r" (cfg));
if (cfg & 2)
__asm__ ("divu %0, %1, %2": "=r" (res):"r" (a), "r" (b));
else
res = __udivmodsi4 (a, b, 0);
if (neg)
res = -res;
}
return res;
}