1 | /* Manipulation of the bit representation of 'long double' quantities. |
2 | Copyright (C) 2001-2023 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <https://www.gnu.org/licenses/>. */ |
18 | |
19 | #ifndef _MATH_LDBL_H_ |
20 | #define _MATH_LDBL_H_ 1 |
21 | |
22 | #include <stdint.h> |
23 | |
24 | /* A union which permits us to convert between a long double and |
25 | three 32 bit ints. */ |
26 | |
27 | typedef union |
28 | { |
29 | long double value; |
30 | struct |
31 | { |
32 | uint32_t lsw; |
33 | uint32_t msw; |
34 | int sign_exponent:16; |
35 | unsigned int empty1:16; |
36 | unsigned int empty0:32; |
37 | } parts; |
38 | } ieee_long_double_shape_type; |
39 | |
40 | /* Get three 32 bit ints from a double. */ |
41 | |
42 | #define GET_LDOUBLE_WORDS(exp,ix0,ix1,d) \ |
43 | do { \ |
44 | ieee_long_double_shape_type ew_u; \ |
45 | ew_u.value = (d); \ |
46 | (exp) = ew_u.parts.sign_exponent; \ |
47 | (ix0) = ew_u.parts.msw; \ |
48 | (ix1) = ew_u.parts.lsw; \ |
49 | } while (0) |
50 | |
51 | /* Set a double from two 32 bit ints. */ |
52 | |
53 | #define SET_LDOUBLE_WORDS(d,exp,ix0,ix1) \ |
54 | do { \ |
55 | ieee_long_double_shape_type iw_u; \ |
56 | iw_u.parts.sign_exponent = (exp); \ |
57 | iw_u.parts.msw = (ix0); \ |
58 | iw_u.parts.lsw = (ix1); \ |
59 | (d) = iw_u.value; \ |
60 | } while (0) |
61 | |
62 | /* Get the more significant 32 bits of a long double mantissa. */ |
63 | |
64 | #define GET_LDOUBLE_MSW(v,d) \ |
65 | do { \ |
66 | ieee_long_double_shape_type sh_u; \ |
67 | sh_u.value = (d); \ |
68 | (v) = sh_u.parts.msw; \ |
69 | } while (0) |
70 | |
71 | /* Set the more significant 32 bits of a long double mantissa from an int. */ |
72 | |
73 | #define SET_LDOUBLE_MSW(d,v) \ |
74 | do { \ |
75 | ieee_long_double_shape_type sh_u; \ |
76 | sh_u.value = (d); \ |
77 | sh_u.parts.msw = (v); \ |
78 | (d) = sh_u.value; \ |
79 | } while (0) |
80 | |
81 | /* Get int from the exponent of a long double. */ |
82 | |
83 | #define GET_LDOUBLE_EXP(exp,d) \ |
84 | do { \ |
85 | ieee_long_double_shape_type ge_u; \ |
86 | ge_u.value = (d); \ |
87 | (exp) = ge_u.parts.sign_exponent; \ |
88 | } while (0) |
89 | |
90 | /* Set exponent of a long double from an int. */ |
91 | |
92 | #define SET_LDOUBLE_EXP(d,exp) \ |
93 | do { \ |
94 | ieee_long_double_shape_type se_u; \ |
95 | se_u.value = (d); \ |
96 | se_u.parts.sign_exponent = (exp); \ |
97 | (d) = se_u.value; \ |
98 | } while (0) |
99 | |
100 | #endif /* math_ldbl.h */ |
101 | |