| 1 | /* Manipulation of the bit representation of 'long double' quantities. |
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| 2 | Copyright (C) 2001-2022 Free Software Foundation, Inc. |
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| 3 | This file is part of the GNU C Library. |
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| 4 | |
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| 5 | The GNU C Library is free software; you can redistribute it and/or |
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| 6 | modify it under the terms of the GNU Lesser General Public |
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| 7 | License as published by the Free Software Foundation; either |
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| 8 | version 2.1 of the License, or (at your option) any later version. |
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| 9 | |
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| 10 | The GNU C Library is distributed in the hope that it will be useful, |
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| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 13 | Lesser General Public License for more details. |
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| 14 | |
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| 15 | You should have received a copy of the GNU Lesser General Public |
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| 16 | License along with the GNU C Library; if not, see |
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| 17 | <https://www.gnu.org/licenses/>. */ |
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| 18 | |
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| 19 | #ifndef _MATH_LDBL_H_ |
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| 20 | #define _MATH_LDBL_H_ 1 |
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| 21 | |
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| 22 | #include <stdint.h> |
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| 23 | |
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| 24 | /* A union which permits us to convert between a long double and |
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| 25 | three 32 bit ints. */ |
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| 26 | |
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| 27 | typedef union |
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| 28 | { |
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| 29 | long double value; |
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| 30 | struct |
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| 31 | { |
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| 32 | uint32_t lsw; |
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| 33 | uint32_t msw; |
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| 34 | int sign_exponent:16; |
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| 35 | unsigned int empty1:16; |
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| 36 | unsigned int empty0:32; |
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| 37 | } parts; |
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| 38 | } ieee_long_double_shape_type; |
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| 39 | |
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| 40 | /* Get three 32 bit ints from a double. */ |
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| 41 | |
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| 42 | #define GET_LDOUBLE_WORDS(exp,ix0,ix1,d) \ |
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| 43 | do { \ |
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| 44 | ieee_long_double_shape_type ew_u; \ |
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| 45 | ew_u.value = (d); \ |
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| 46 | (exp) = ew_u.parts.sign_exponent; \ |
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| 47 | (ix0) = ew_u.parts.msw; \ |
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| 48 | (ix1) = ew_u.parts.lsw; \ |
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| 49 | } while (0) |
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| 50 | |
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| 51 | /* Set a double from two 32 bit ints. */ |
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| 52 | |
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| 53 | #define SET_LDOUBLE_WORDS(d,exp,ix0,ix1) \ |
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| 54 | do { \ |
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| 55 | ieee_long_double_shape_type iw_u; \ |
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| 56 | iw_u.parts.sign_exponent = (exp); \ |
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| 57 | iw_u.parts.msw = (ix0); \ |
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| 58 | iw_u.parts.lsw = (ix1); \ |
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| 59 | (d) = iw_u.value; \ |
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| 60 | } while (0) |
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| 61 | |
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| 62 | /* Get the more significant 32 bits of a long double mantissa. */ |
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| 63 | |
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| 64 | #define GET_LDOUBLE_MSW(v,d) \ |
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| 65 | do { \ |
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| 66 | ieee_long_double_shape_type sh_u; \ |
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| 67 | sh_u.value = (d); \ |
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| 68 | (v) = sh_u.parts.msw; \ |
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| 69 | } while (0) |
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| 70 | |
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| 71 | /* Set the more significant 32 bits of a long double mantissa from an int. */ |
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| 72 | |
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| 73 | #define SET_LDOUBLE_MSW(d,v) \ |
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| 74 | do { \ |
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| 75 | ieee_long_double_shape_type sh_u; \ |
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| 76 | sh_u.value = (d); \ |
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| 77 | sh_u.parts.msw = (v); \ |
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| 78 | (d) = sh_u.value; \ |
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| 79 | } while (0) |
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| 80 | |
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| 81 | /* Get int from the exponent of a long double. */ |
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| 82 | |
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| 83 | #define GET_LDOUBLE_EXP(exp,d) \ |
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| 84 | do { \ |
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| 85 | ieee_long_double_shape_type ge_u; \ |
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| 86 | ge_u.value = (d); \ |
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| 87 | (exp) = ge_u.parts.sign_exponent; \ |
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| 88 | } while (0) |
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| 89 | |
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| 90 | /* Set exponent of a long double from an int. */ |
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| 91 | |
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| 92 | #define SET_LDOUBLE_EXP(d,exp) \ |
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| 93 | do { \ |
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| 94 | ieee_long_double_shape_type se_u; \ |
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| 95 | se_u.value = (d); \ |
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| 96 | se_u.parts.sign_exponent = (exp); \ |
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| 97 | (d) = se_u.value; \ |
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| 98 | } while (0) |
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| 99 | |
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| 100 | #endif /* math_ldbl.h */ |
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| 101 | |
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