Get rid of SINGLE_ONLY_FPU. Linux does not support half FPU other than
[linux-2.6.git] / arch / mips / math-emu / dp_fsp.c
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
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 }