1 /* IEEE754 floating point arithmetic
2 * double precision: common utilities
3 */
4 /*
5 * MIPS floating point support
6 * Copyright (C) 1994-2000 Algorithmics Ltd.
7 * http://www.algor.co.uk
8 *
9 * ########################################################################
10 *
11 * This program is free software; you can distribute it and/or modify it
12 * under the terms of the GNU General Public License (Version 2) as
13 * published by the Free Software Foundation.
14 *
15 * This program is distributed in the hope it will be useful, but WITHOUT
16 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
17 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 * for more details.
19 *
20 * You should have received a copy of the GNU General Public License along
21 * with this program; if not, write to the Free Software Foundation, Inc.,
22 * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
23 *
24 * ########################################################################
25 */
26
27
28 #include "ieee754dp.h"
29
ieee754dp_fsp(ieee754sp x)30 ieee754dp ieee754dp_fsp(ieee754sp x)
31 {
32 COMPXSP;
33
34 EXPLODEXSP;
35
36 CLEARCX;
37
38 FLUSHXSP;
39
40 switch (xc) {
41 case IEEE754_CLASS_SNAN:
42 SETCX(IEEE754_INVALID_OPERATION);
43 return ieee754dp_nanxcpt(ieee754dp_indef(), "fsp");
44 case IEEE754_CLASS_QNAN:
45 return ieee754dp_nanxcpt(builddp(xs,
46 DP_EMAX + 1 + DP_EBIAS,
47 ((u64) xm
48 << (DP_MBITS -
49 SP_MBITS))), "fsp",
50 x);
51 case IEEE754_CLASS_INF:
52 return ieee754dp_inf(xs);
53 case IEEE754_CLASS_ZERO:
54 return ieee754dp_zero(xs);
55 case IEEE754_CLASS_DNORM:
56 /* normalize */
57 while ((xm >> SP_MBITS) == 0) {
58 xm <<= 1;
59 xe--;
60 }
61 break;
62 case IEEE754_CLASS_NORM:
63 break;
64 }
65
66 /* CANT possibly overflow,underflow, or need rounding
67 */
68
69 /* drop the hidden bit */
70 xm &= ~SP_HIDDEN_BIT;
71
72 return builddp(xs, xe + DP_EBIAS,
73 (u64) xm << (DP_MBITS - SP_MBITS));
74 }
75