50a23e6eec
The patch below updates broken web addresses in the arch directory. Signed-off-by: Justin P. Mattock <justinmattock@gmail.com> Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: Finn Thain <fthain@telegraphics.com.au> Cc: Randy Dunlap <rdunlap@xenotime.net> Reviewed-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
156 lines
4.2 KiB
C
156 lines
4.2 KiB
C
/* IEEE754 floating point arithmetic
|
|
* single precision
|
|
*/
|
|
/*
|
|
* MIPS floating point support
|
|
* Copyright (C) 1994-2000 Algorithmics Ltd.
|
|
*
|
|
* ########################################################################
|
|
*
|
|
* This program is free software; you can distribute it and/or modify it
|
|
* under the terms of the GNU General Public License (Version 2) as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope 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 this program; if not, write to the Free Software Foundation, Inc.,
|
|
* 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
|
|
*
|
|
* ########################################################################
|
|
*/
|
|
|
|
|
|
#include "ieee754sp.h"
|
|
|
|
ieee754sp ieee754sp_div(ieee754sp x, ieee754sp y)
|
|
{
|
|
COMPXSP;
|
|
COMPYSP;
|
|
|
|
EXPLODEXSP;
|
|
EXPLODEYSP;
|
|
|
|
CLEARCX;
|
|
|
|
FLUSHXSP;
|
|
FLUSHYSP;
|
|
|
|
switch (CLPAIR(xc, yc)) {
|
|
case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_QNAN):
|
|
case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_SNAN):
|
|
case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_SNAN):
|
|
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_SNAN):
|
|
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_SNAN):
|
|
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_SNAN):
|
|
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_SNAN):
|
|
case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_ZERO):
|
|
case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_NORM):
|
|
case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_DNORM):
|
|
case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_INF):
|
|
SETCX(IEEE754_INVALID_OPERATION);
|
|
return ieee754sp_nanxcpt(ieee754sp_indef(), "div", x, y);
|
|
|
|
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_QNAN):
|
|
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_QNAN):
|
|
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_QNAN):
|
|
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_QNAN):
|
|
return y;
|
|
|
|
case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_QNAN):
|
|
case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_ZERO):
|
|
case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_NORM):
|
|
case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_DNORM):
|
|
case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_INF):
|
|
return x;
|
|
|
|
|
|
/* Infinity handling
|
|
*/
|
|
|
|
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
|
|
SETCX(IEEE754_INVALID_OPERATION);
|
|
return ieee754sp_xcpt(ieee754sp_indef(), "div", x, y);
|
|
|
|
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
|
|
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):
|
|
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
|
|
return ieee754sp_zero(xs ^ ys);
|
|
|
|
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
|
|
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM):
|
|
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM):
|
|
return ieee754sp_inf(xs ^ ys);
|
|
|
|
/* Zero handling
|
|
*/
|
|
|
|
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO):
|
|
SETCX(IEEE754_INVALID_OPERATION);
|
|
return ieee754sp_xcpt(ieee754sp_indef(), "div", x, y);
|
|
|
|
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO):
|
|
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
|
|
SETCX(IEEE754_ZERO_DIVIDE);
|
|
return ieee754sp_xcpt(ieee754sp_inf(xs ^ ys), "div", x, y);
|
|
|
|
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_NORM):
|
|
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_DNORM):
|
|
return ieee754sp_zero(xs == ys ? 0 : 1);
|
|
|
|
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_DNORM):
|
|
SPDNORMX;
|
|
|
|
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_DNORM):
|
|
SPDNORMY;
|
|
break;
|
|
|
|
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_NORM):
|
|
SPDNORMX;
|
|
break;
|
|
|
|
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_NORM):
|
|
break;
|
|
}
|
|
assert(xm & SP_HIDDEN_BIT);
|
|
assert(ym & SP_HIDDEN_BIT);
|
|
|
|
/* provide rounding space */
|
|
xm <<= 3;
|
|
ym <<= 3;
|
|
|
|
{
|
|
/* now the dirty work */
|
|
|
|
unsigned rm = 0;
|
|
int re = xe - ye;
|
|
unsigned bm;
|
|
|
|
for (bm = SP_MBIT(SP_MBITS + 2); bm; bm >>= 1) {
|
|
if (xm >= ym) {
|
|
xm -= ym;
|
|
rm |= bm;
|
|
if (xm == 0)
|
|
break;
|
|
}
|
|
xm <<= 1;
|
|
}
|
|
rm <<= 1;
|
|
if (xm)
|
|
rm |= 1; /* have remainder, set sticky */
|
|
|
|
assert(rm);
|
|
|
|
/* normalise rm to rounding precision ?
|
|
*/
|
|
while ((rm >> (SP_MBITS + 3)) == 0) {
|
|
rm <<= 1;
|
|
re--;
|
|
}
|
|
|
|
SPNORMRET2(xs == ys ? 0 : 1, re, rm, "div", x, y);
|
|
}
|
|
}
|