1/* IEEE754 floating point arithmetic
2 * single precision
3 */
4/*
5 * MIPS floating point support
6 * Copyright (C) 1994-2000 Algorithmics Ltd.
7 *
8 *  This program is free software; you can distribute it and/or modify it
9 *  under the terms of the GNU General Public License (Version 2) as
10 *  published by the Free Software Foundation.
11 *
12 *  This program is distributed in the hope it will be useful, but WITHOUT
13 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15 *  for more details.
16 *
17 *  You should have received a copy of the GNU General Public License along
18 *  with this program; if not, write to the Free Software Foundation, Inc.,
19 *  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA.
20 */
21
22#include "ieee754sp.h"
23
24union ieee754sp ieee754sp_fint(int x)
25{
26	unsigned xm;
27	int xe;
28	int xs;
29
30	ieee754_clearcx();
31
32	if (x == 0)
33		return ieee754sp_zero(0);
34	if (x == 1 || x == -1)
35		return ieee754sp_one(x < 0);
36	if (x == 10 || x == -10)
37		return ieee754sp_ten(x < 0);
38
39	xs = (x < 0);
40	if (xs) {
41		if (x == (1 << 31))
42			xm = ((unsigned) 1 << 31);	/* max neg can't be safely negated */
43		else
44			xm = -x;
45	} else {
46		xm = x;
47	}
48	xe = SP_FBITS + 3;
49
50	if (xm >> (SP_FBITS + 1 + 3)) {
51		/* shunt out overflow bits
52		 */
53		while (xm >> (SP_FBITS + 1 + 3)) {
54			SPXSRSX1();
55		}
56	} else {
57		/* normalize in grs extended single precision
58		 */
59		while ((xm >> (SP_FBITS + 3)) == 0) {
60			xm <<= 1;
61			xe--;
62		}
63	}
64	return ieee754sp_format(xs, xe, xm);
65}
66