1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
|
/* Copyright (C) 1992, 1995, 1996, 1998 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#ifndef _IEEE754_H
#define _IEEE754_H 1
#include <features.h>
#include <endian.h>
__BEGIN_DECLS
union ieee754_float
{
float f;
/* This is the IEEE 754 single-precision format. */
struct
{
unsigned int mantissa:23;
unsigned int exponent:8;
unsigned int negative:1;
} ieee;
/* This format makes it easier to see if a NaN is a signalling NaN. */
struct
{
unsigned int mantissa:22;
unsigned int quiet_nan:1;
unsigned int exponent:8;
unsigned int negative:1;
} ieee_nan;
};
#define IEEE754_FLOAT_BIAS 0x7f /* Added to exponent. */
union ieee754_double
{
double d;
/* This is the IEEE 754 double-precision format. */
struct
{
unsigned int mantissa0:20;
unsigned int exponent:11;
unsigned int negative:1;
unsigned int mantissa1:32;
} ieee;
/* This format makes it easier to see if a NaN is a signalling NaN. */
struct
{
unsigned int mantissa0:19;
unsigned int quiet_nan:1;
unsigned int exponent:11;
unsigned int negative:1;
unsigned int mantissa1:32;
} ieee_nan;
};
#define IEEE754_DOUBLE_BIAS 0x3ff /* Added to exponent. */
/* The following two structures are correct for `new' floating point systems but
wrong for the old FPPC. The only solution seems to be to avoid their use on
old hardware. */
union ieee854_long_double
{
long double d;
/* This is the IEEE 854 double-extended-precision format. */
struct
{
unsigned int exponent:15;
unsigned int empty:16;
unsigned int negative:1;
unsigned int mantissa1:32;
unsigned int mantissa0:32;
} ieee;
/* This is for NaNs in the IEEE 854 double-extended-precision format. */
struct
{
unsigned int exponent:15;
unsigned int empty:16;
unsigned int negative:1;
unsigned int mantissa1:32;
unsigned int mantissa0:30;
unsigned int quiet_nan:1;
unsigned int one:1;
} ieee_nan;
};
#define IEEE854_LONG_DOUBLE_BIAS 0x3fff
__END_DECLS
#endif /* ieee754.h */
|
