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 *
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 #include "ieee754dp.h"
24
ieee754dp_nan_fsp(int xs,u64 xm)25 static inline union ieee754dp ieee754dp_nan_fsp(int xs, u64 xm)
26 {
27 return builddp(xs, DP_EMAX + 1 + DP_EBIAS,
28 xm << (DP_FBITS - SP_FBITS));
29 }
30
ieee754dp_fsp(union ieee754sp x)31 union ieee754dp ieee754dp_fsp(union ieee754sp x)
32 {
33 COMPXSP;
34
35 EXPLODEXSP;
36
37 ieee754_clearcx();
38
39 FLUSHXSP;
40
41 switch (xc) {
42 case IEEE754_CLASS_SNAN:
43 return ieee754dp_nanxcpt(ieee754dp_nan_fsp(xs, xm));
44
45 case IEEE754_CLASS_QNAN:
46 return ieee754dp_nan_fsp(xs, xm);
47
48 case IEEE754_CLASS_INF:
49 return ieee754dp_inf(xs);
50
51 case IEEE754_CLASS_ZERO:
52 return ieee754dp_zero(xs);
53
54 case IEEE754_CLASS_DNORM:
55 /* normalize */
56 while ((xm >> SP_FBITS) == 0) {
57 xm <<= 1;
58 xe--;
59 }
60 break;
61
62 case IEEE754_CLASS_NORM:
63 break;
64 }
65
66 /*
67 * Can't possibly overflow,underflow, or need rounding
68 */
69
70 /* drop the hidden bit */
71 xm &= ~SP_HIDDEN_BIT;
72
73 return builddp(xs, xe + DP_EBIAS,
74 (u64) xm << (DP_FBITS - SP_FBITS));
75 }
76