1 /* IEEE754 floating point arithmetic
5 * MIPS floating point support
6 * Copyright (C) 1994-2000 Algorithmics Ltd.
7 * http://www.algor.co.uk
9 * ########################################################################
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.
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
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.
24 * ########################################################################
28 #include <linux/kernel.h>
29 #include "ieee754sp.h"
31 int ieee754sp_tint(ieee754sp x
)
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
:
48 case IEEE754_CLASS_DNORM
:
49 case IEEE754_CLASS_NORM
:
53 /* look for valid corner case */
54 if (xe
== 31 && xs
&& xm
== SP_HIDDEN_BIT
)
56 /* Set invalid. We will only use overflow for floating
58 SETCX(IEEE754_INVALID_OPERATION
);
59 return ieee754si_xcpt(ieee754si_indef(), "sp_tint", x
);
73 sticky
= residue
!= 0;
76 /* Shifting a u32 32 times does not work,
77 * so we do it in two steps. Be aware that xe
79 residue
= xm
<< (xe
+ 1);
80 residue
<<= 31 - SP_MBITS
;
81 round
= (residue
>> 31) != 0;
82 sticky
= (residue
<< 1) != 0;
85 odd
= (xm
& 0x1) != 0x0;
86 switch (ieee754_csr
.rm
) {
88 if (round
&& (sticky
|| odd
))
93 case IEEE754_RU
: /* toward +Infinity */
94 if ((round
|| sticky
) && !xs
)
97 case IEEE754_RD
: /* toward -Infinity */
98 if ((round
|| sticky
) && xs
)
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
);
108 SETCX(IEEE754_INEXACT
);
117 unsigned int ieee754sp_tuns(ieee754sp x
)
119 ieee754sp hb
= ieee754sp_1e31();
121 /* what if x < 0 ?? */
122 if (ieee754sp_lt(x
, hb
))
123 return (unsigned) ieee754sp_tint(x
);
125 return (unsigned) ieee754sp_tint(ieee754sp_sub(x
, hb
)) |
126 ((unsigned) 1 << 31);