xf.li | bdd93d5 | 2023-05-12 07:10:14 -0700 | [diff] [blame^] | 1 | /* Copyright (C) 2000-2016 Free Software Foundation, Inc. |
| 2 | This file is part of the GNU C Library. |
| 3 | |
| 4 | The GNU C Library is free software; you can redistribute it and/or |
| 5 | modify it under the terms of the GNU Lesser General Public |
| 6 | License as published by the Free Software Foundation; either |
| 7 | version 2.1 of the License, or (at your option) any later version. |
| 8 | |
| 9 | The GNU C Library is distributed in the hope that it will be useful, |
| 10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | Lesser General Public License for more details. |
| 13 | |
| 14 | You should have received a copy of the GNU Lesser General Public |
| 15 | License along with the GNU C Library; if not, see |
| 16 | <http://www.gnu.org/licenses/>. */ |
| 17 | |
| 18 | #ifndef _IEEE754_H |
| 19 | |
| 20 | #define _IEEE754_H 1 |
| 21 | #include <features.h> |
| 22 | |
| 23 | #include <endian.h> |
| 24 | |
| 25 | __BEGIN_DECLS |
| 26 | |
| 27 | union ieee754_float |
| 28 | { |
| 29 | float f; |
| 30 | |
| 31 | /* This is the IEEE 754 single-precision format. */ |
| 32 | struct |
| 33 | { |
| 34 | #if __BYTE_ORDER == __BIG_ENDIAN |
| 35 | unsigned int negative:1; |
| 36 | unsigned int exponent:8; |
| 37 | unsigned int mantissa:23; |
| 38 | #endif /* Big endian. */ |
| 39 | #if __BYTE_ORDER == __LITTLE_ENDIAN |
| 40 | unsigned int mantissa:23; |
| 41 | unsigned int exponent:8; |
| 42 | unsigned int negative:1; |
| 43 | #endif /* Little endian. */ |
| 44 | } ieee; |
| 45 | |
| 46 | /* This format makes it easier to see if a NaN is a signalling NaN. */ |
| 47 | struct |
| 48 | { |
| 49 | #if __BYTE_ORDER == __BIG_ENDIAN |
| 50 | unsigned int negative:1; |
| 51 | unsigned int exponent:8; |
| 52 | unsigned int quiet_nan:1; |
| 53 | unsigned int mantissa:22; |
| 54 | #endif /* Big endian. */ |
| 55 | #if __BYTE_ORDER == __LITTLE_ENDIAN |
| 56 | unsigned int mantissa:22; |
| 57 | unsigned int quiet_nan:1; |
| 58 | unsigned int exponent:8; |
| 59 | unsigned int negative:1; |
| 60 | #endif /* Little endian. */ |
| 61 | } ieee_nan; |
| 62 | }; |
| 63 | |
| 64 | #define IEEE754_FLOAT_BIAS 0x7f /* Added to exponent. */ |
| 65 | |
| 66 | |
| 67 | union ieee754_double |
| 68 | { |
| 69 | double d; |
| 70 | |
| 71 | /* This is the IEEE 754 double-precision format. */ |
| 72 | struct |
| 73 | { |
| 74 | #if __BYTE_ORDER == __BIG_ENDIAN |
| 75 | unsigned int negative:1; |
| 76 | unsigned int exponent:11; |
| 77 | /* Together these comprise the mantissa. */ |
| 78 | unsigned int mantissa0:20; |
| 79 | unsigned int mantissa1:32; |
| 80 | #endif /* Big endian. */ |
| 81 | #if __BYTE_ORDER == __LITTLE_ENDIAN |
| 82 | # if __FLOAT_WORD_ORDER == __BIG_ENDIAN |
| 83 | unsigned int mantissa0:20; |
| 84 | unsigned int exponent:11; |
| 85 | unsigned int negative:1; |
| 86 | unsigned int mantissa1:32; |
| 87 | # else |
| 88 | /* Together these comprise the mantissa. */ |
| 89 | unsigned int mantissa1:32; |
| 90 | unsigned int mantissa0:20; |
| 91 | unsigned int exponent:11; |
| 92 | unsigned int negative:1; |
| 93 | # endif |
| 94 | #endif /* Little endian. */ |
| 95 | } ieee; |
| 96 | |
| 97 | /* This format makes it easier to see if a NaN is a signalling NaN. */ |
| 98 | struct |
| 99 | { |
| 100 | #if __BYTE_ORDER == __BIG_ENDIAN |
| 101 | unsigned int negative:1; |
| 102 | unsigned int exponent:11; |
| 103 | unsigned int quiet_nan:1; |
| 104 | /* Together these comprise the mantissa. */ |
| 105 | unsigned int mantissa0:19; |
| 106 | unsigned int mantissa1:32; |
| 107 | #else |
| 108 | # if __FLOAT_WORD_ORDER == __BIG_ENDIAN |
| 109 | unsigned int mantissa0:19; |
| 110 | unsigned int quiet_nan:1; |
| 111 | unsigned int exponent:11; |
| 112 | unsigned int negative:1; |
| 113 | unsigned int mantissa1:32; |
| 114 | # else |
| 115 | /* Together these comprise the mantissa. */ |
| 116 | unsigned int mantissa1:32; |
| 117 | unsigned int mantissa0:19; |
| 118 | unsigned int quiet_nan:1; |
| 119 | unsigned int exponent:11; |
| 120 | unsigned int negative:1; |
| 121 | # endif |
| 122 | #endif |
| 123 | } ieee_nan; |
| 124 | }; |
| 125 | |
| 126 | #define IEEE754_DOUBLE_BIAS 0x3ff /* Added to exponent. */ |
| 127 | |
| 128 | |
| 129 | union ieee854_long_double |
| 130 | { |
| 131 | long double d; |
| 132 | |
| 133 | /* This is the IEEE 854 double-extended-precision format. */ |
| 134 | struct |
| 135 | { |
| 136 | #if __BYTE_ORDER == __BIG_ENDIAN |
| 137 | unsigned int empty0:32; |
| 138 | unsigned int negative:1; |
| 139 | unsigned int exponent:15; |
| 140 | unsigned int empty1:16; |
| 141 | unsigned int mantissa0:32; |
| 142 | unsigned int mantissa1:32; |
| 143 | #endif |
| 144 | #if __BYTE_ORDER == __LITTLE_ENDIAN |
| 145 | # if __FLOAT_WORD_ORDER == __BIG_ENDIAN |
| 146 | unsigned int empty0:32; |
| 147 | unsigned int exponent:15; |
| 148 | unsigned int negative:1; |
| 149 | unsigned int empty1:16; |
| 150 | unsigned int mantissa0:32; |
| 151 | unsigned int mantissa1:32; |
| 152 | # else |
| 153 | unsigned int mantissa1:32; |
| 154 | unsigned int mantissa0:32; |
| 155 | unsigned int exponent:15; |
| 156 | unsigned int negative:1; |
| 157 | unsigned int empty1:16; |
| 158 | unsigned int empty0:32; |
| 159 | # endif |
| 160 | #endif |
| 161 | } ieee; |
| 162 | |
| 163 | /* This is for NaNs in the IEEE 854 double-extended-precision format. */ |
| 164 | struct |
| 165 | { |
| 166 | #if __BYTE_ORDER == __BIG_ENDIAN |
| 167 | unsigned int empty0:32; |
| 168 | unsigned int negative:1; |
| 169 | unsigned int exponent:15; |
| 170 | unsigned int empty1:16; |
| 171 | unsigned int one:1; |
| 172 | unsigned int quiet_nan:1; |
| 173 | unsigned int mantissa0:30; |
| 174 | unsigned int mantissa1:32; |
| 175 | #endif |
| 176 | #if __BYTE_ORDER == __LITTLE_ENDIAN |
| 177 | # if __FLOAT_WORD_ORDER == __BIG_ENDIAN |
| 178 | unsigned int empty0:32; |
| 179 | unsigned int exponent:15; |
| 180 | unsigned int negative:1; |
| 181 | unsigned int empty1:16; |
| 182 | unsigned int mantissa0:30; |
| 183 | unsigned int quiet_nan:1; |
| 184 | unsigned int one:1; |
| 185 | unsigned int mantissa1:32; |
| 186 | # else |
| 187 | unsigned int mantissa1:32; |
| 188 | unsigned int mantissa0:30; |
| 189 | unsigned int quiet_nan:1; |
| 190 | unsigned int one:1; |
| 191 | unsigned int exponent:15; |
| 192 | unsigned int negative:1; |
| 193 | unsigned int empty1:16; |
| 194 | unsigned int empty0:32; |
| 195 | # endif |
| 196 | #endif |
| 197 | } ieee_nan; |
| 198 | }; |
| 199 | |
| 200 | #define IEEE854_LONG_DOUBLE_BIAS 0x3fff |
| 201 | |
| 202 | __END_DECLS |
| 203 | |
| 204 | #endif /* ieee754.h */ |