1 /* Manipulation of the bit representation of 'long double' quantities. 2 Copyright (C) 2001-2022 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