1 /* IEEE754 floating point arithmetic
2 * single precision
3 */
4 /*
5 * MIPS floating point support
6 * Copyright (C) 1994-2000 Algorithmics Ltd.
7 *
8 * ########################################################################
9 *
10 * This program is free software; you can distribute it and/or modify it
11 * under the terms of the GNU General Public License (Version 2) as
12 * published by the Free Software Foundation.
13 *
14 * This program is distributed in the hope it will be useful, but WITHOUT
15 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
16 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 * for more details.
18 *
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write to the Free Software Foundation, Inc.,
21 * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
22 *
23 * ########################################################################
24 */
25
26
27 #include "ieee754sp.h"
28
ieee754sp_fint(int x)29 ieee754sp ieee754sp_fint(int x)
30 {
31 unsigned xm;
32 int xe;
33 int xs;
34
35 CLEARCX;
36
37 if (x == 0)
38 return ieee754sp_zero(0);
39 if (x == 1 || x == -1)
40 return ieee754sp_one(x < 0);
41 if (x == 10 || x == -10)
42 return ieee754sp_ten(x < 0);
43
44 xs = (x < 0);
45 if (xs) {
46 if (x == (1 << 31))
47 xm = ((unsigned) 1 << 31); /* max neg can't be safely negated */
48 else
49 xm = -x;
50 } else {
51 xm = x;
52 }
53 xe = SP_MBITS + 3;
54
55 if (xm >> (SP_MBITS + 1 + 3)) {
56 /* shunt out overflow bits
57 */
58 while (xm >> (SP_MBITS + 1 + 3)) {
59 SPXSRSX1();
60 }
61 } else {
62 /* normalize in grs extended single precision
63 */
64 while ((xm >> (SP_MBITS + 3)) == 0) {
65 xm <<= 1;
66 xe--;
67 }
68 }
69 SPNORMRET1(xs, xe, xm, "fint", x);
70 }
71
72
ieee754sp_funs(unsigned int u)73 ieee754sp ieee754sp_funs(unsigned int u)
74 {
75 if ((int) u < 0)
76 return ieee754sp_add(ieee754sp_1e31(),
77 ieee754sp_fint(u & ~(1 << 31)));
78 return ieee754sp_fint(u);
79 }
80