1/* Manipulation of the bit representation of 'long double' quantities.
2 Copyright (C) 2001-2020 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
27typedef 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) \
43do { \
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) \
54do { \
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) \
65do { \
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) \
74do { \
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) \
84do { \
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) \
93do { \
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