sp_fint.c
1.82 KB
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/* 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_fint(int x)
{
unsigned xm;
int xe;
int xs;
CLEARCX;
if (x == 0)
return ieee754sp_zero(0);
if (x == 1 || x == -1)
return ieee754sp_one(x < 0);
if (x == 10 || x == -10)
return ieee754sp_ten(x < 0);
xs = (x < 0);
if (xs) {
if (x == (1 << 31))
xm = ((unsigned) 1 << 31); /* max neg can't be safely negated */
else
xm = -x;
} else {
xm = x;
}
xe = SP_MBITS + 3;
if (xm >> (SP_MBITS + 1 + 3)) {
/* shunt out overflow bits
*/
while (xm >> (SP_MBITS + 1 + 3)) {
SPXSRSX1();
}
} else {
/* normalize in grs extended single precision
*/
while ((xm >> (SP_MBITS + 3)) == 0) {
xm <<= 1;
xe--;
}
}
SPNORMRET1(xs, xe, xm, "fint", x);
}
ieee754sp ieee754sp_funs(unsigned int u)
{
if ((int) u < 0)
return ieee754sp_add(ieee754sp_1e31(),
ieee754sp_fint(u & ~(1 << 31)));
return ieee754sp_fint(u);
}