MIPS: math-emu: Checkpatch cleanup
[sfrench/cifs-2.6.git] / arch / mips / math-emu / sp_tint.c
1 /* IEEE754 floating point arithmetic
2  * single precision
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 <linux/kernel.h>
29 #include "ieee754sp.h"
30
31 int ieee754sp_tint(ieee754sp x)
32 {
33         COMPXSP;
34
35         CLEARCX;
36
37         EXPLODEXSP;
38         FLUSHXSP;
39
40         switch (xc) {
41         case IEEE754_CLASS_SNAN:
42         case IEEE754_CLASS_QNAN:
43         case IEEE754_CLASS_INF:
44                 SETCX(IEEE754_INVALID_OPERATION);
45                 return ieee754si_xcpt(ieee754si_indef(), "sp_tint", x);
46         case IEEE754_CLASS_ZERO:
47                 return 0;
48         case IEEE754_CLASS_DNORM:
49         case IEEE754_CLASS_NORM:
50                 break;
51         }
52         if (xe >= 31) {
53                 /* look for valid corner case */
54                 if (xe == 31 && xs && xm == SP_HIDDEN_BIT)
55                         return -0x80000000;
56                 /* Set invalid. We will only use overflow for floating
57                    point overflow */
58                 SETCX(IEEE754_INVALID_OPERATION);
59                 return ieee754si_xcpt(ieee754si_indef(), "sp_tint", x);
60         }
61         /* oh gawd */
62         if (xe > SP_MBITS) {
63                 xm <<= xe - SP_MBITS;
64         } else {
65                 u32 residue;
66                 int round;
67                 int sticky;
68                 int odd;
69
70                 if (xe < -1) {
71                         residue = xm;
72                         round = 0;
73                         sticky = residue != 0;
74                         xm = 0;
75                 } else {
76                         /* Shifting a u32 32 times does not work,
77                         * so we do it in two steps. Be aware that xe
78                         * may be -1 */
79                         residue = xm << (xe + 1);
80                         residue <<= 31 - SP_MBITS;
81                         round = (residue >> 31) != 0;
82                         sticky = (residue << 1) != 0;
83                         xm >>= SP_MBITS - xe;
84                 }
85                 odd = (xm & 0x1) != 0x0;
86                 switch (ieee754_csr.rm) {
87                 case IEEE754_RN:
88                         if (round && (sticky || odd))
89                                 xm++;
90                         break;
91                 case IEEE754_RZ:
92                         break;
93                 case IEEE754_RU:        /* toward +Infinity */
94                         if ((round || sticky) && !xs)
95                                 xm++;
96                         break;
97                 case IEEE754_RD:        /* toward -Infinity */
98                         if ((round || sticky) && xs)
99                                 xm++;
100                         break;
101                 }
102                 if ((xm >> 31) != 0) {
103                         /* This can happen after rounding */
104                         SETCX(IEEE754_INVALID_OPERATION);
105                         return ieee754si_xcpt(ieee754si_indef(), "sp_tint", x);
106                 }
107                 if (round || sticky)
108                         SETCX(IEEE754_INEXACT);
109         }
110         if (xs)
111                 return -xm;
112         else
113                 return xm;
114 }
115
116
117 unsigned int ieee754sp_tuns(ieee754sp x)
118 {
119         ieee754sp hb = ieee754sp_1e31();
120
121         /* what if x < 0 ?? */
122         if (ieee754sp_lt(x, hb))
123                 return (unsigned) ieee754sp_tint(x);
124
125         return (unsigned) ieee754sp_tint(ieee754sp_sub(x, hb)) |
126             ((unsigned) 1 << 31);
127 }