lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame] | 1 | /* Software floating-point emulation. |
| 2 | Basic eight-word fraction declaration and manipulation. |
| 3 | Copyright (C) 1997-2015 Free Software Foundation, Inc. |
| 4 | This file is part of the GNU C Library. |
| 5 | Contributed by Richard Henderson (rth@cygnus.com), |
| 6 | Jakub Jelinek (jj@ultra.linux.cz) and |
| 7 | Peter Maydell (pmaydell@chiark.greenend.org.uk). |
| 8 | |
| 9 | The GNU C Library is free software; you can redistribute it and/or |
| 10 | modify it under the terms of the GNU Lesser General Public |
| 11 | License as published by the Free Software Foundation; either |
| 12 | version 2.1 of the License, or (at your option) any later version. |
| 13 | |
| 14 | In addition to the permissions in the GNU Lesser General Public |
| 15 | License, the Free Software Foundation gives you unlimited |
| 16 | permission to link the compiled version of this file into |
| 17 | combinations with other programs, and to distribute those |
| 18 | combinations without any restriction coming from the use of this |
| 19 | file. (The Lesser General Public License restrictions do apply in |
| 20 | other respects; for example, they cover modification of the file, |
| 21 | and distribution when not linked into a combine executable.) |
| 22 | |
| 23 | The GNU C Library is distributed in the hope that it will be useful, |
| 24 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 25 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 26 | Lesser General Public License for more details. |
| 27 | |
| 28 | You should have received a copy of the GNU Lesser General Public |
| 29 | License along with the GNU C Library; if not, see |
| 30 | <http://www.gnu.org/licenses/>. */ |
| 31 | |
| 32 | #ifndef SOFT_FP_OP_8_H |
| 33 | #define SOFT_FP_OP_8_H 1 |
| 34 | |
| 35 | /* We need just a few things from here for op-4, if we ever need some |
| 36 | other macros, they can be added. */ |
| 37 | #define _FP_FRAC_DECL_8(X) _FP_W_TYPE X##_f[8] |
| 38 | #define _FP_FRAC_HIGH_8(X) (X##_f[7]) |
| 39 | #define _FP_FRAC_LOW_8(X) (X##_f[0]) |
| 40 | #define _FP_FRAC_WORD_8(X, w) (X##_f[w]) |
| 41 | |
| 42 | #define _FP_FRAC_SLL_8(X, N) \ |
| 43 | do \ |
| 44 | { \ |
| 45 | _FP_I_TYPE _FP_FRAC_SLL_8_up, _FP_FRAC_SLL_8_down; \ |
| 46 | _FP_I_TYPE _FP_FRAC_SLL_8_skip, _FP_FRAC_SLL_8_i; \ |
| 47 | _FP_FRAC_SLL_8_skip = (N) / _FP_W_TYPE_SIZE; \ |
| 48 | _FP_FRAC_SLL_8_up = (N) % _FP_W_TYPE_SIZE; \ |
| 49 | _FP_FRAC_SLL_8_down = _FP_W_TYPE_SIZE - _FP_FRAC_SLL_8_up; \ |
| 50 | if (!_FP_FRAC_SLL_8_up) \ |
| 51 | for (_FP_FRAC_SLL_8_i = 7; \ |
| 52 | _FP_FRAC_SLL_8_i >= _FP_FRAC_SLL_8_skip; \ |
| 53 | --_FP_FRAC_SLL_8_i) \ |
| 54 | X##_f[_FP_FRAC_SLL_8_i] \ |
| 55 | = X##_f[_FP_FRAC_SLL_8_i-_FP_FRAC_SLL_8_skip]; \ |
| 56 | else \ |
| 57 | { \ |
| 58 | for (_FP_FRAC_SLL_8_i = 7; \ |
| 59 | _FP_FRAC_SLL_8_i > _FP_FRAC_SLL_8_skip; \ |
| 60 | --_FP_FRAC_SLL_8_i) \ |
| 61 | X##_f[_FP_FRAC_SLL_8_i] \ |
| 62 | = ((X##_f[_FP_FRAC_SLL_8_i-_FP_FRAC_SLL_8_skip] \ |
| 63 | << _FP_FRAC_SLL_8_up) \ |
| 64 | | (X##_f[_FP_FRAC_SLL_8_i-_FP_FRAC_SLL_8_skip-1] \ |
| 65 | >> _FP_FRAC_SLL_8_down)); \ |
| 66 | X##_f[_FP_FRAC_SLL_8_i--] = X##_f[0] << _FP_FRAC_SLL_8_up; \ |
| 67 | } \ |
| 68 | for (; _FP_FRAC_SLL_8_i >= 0; --_FP_FRAC_SLL_8_i) \ |
| 69 | X##_f[_FP_FRAC_SLL_8_i] = 0; \ |
| 70 | } \ |
| 71 | while (0) |
| 72 | |
| 73 | #define _FP_FRAC_SRL_8(X, N) \ |
| 74 | do \ |
| 75 | { \ |
| 76 | _FP_I_TYPE _FP_FRAC_SRL_8_up, _FP_FRAC_SRL_8_down; \ |
| 77 | _FP_I_TYPE _FP_FRAC_SRL_8_skip, _FP_FRAC_SRL_8_i; \ |
| 78 | _FP_FRAC_SRL_8_skip = (N) / _FP_W_TYPE_SIZE; \ |
| 79 | _FP_FRAC_SRL_8_down = (N) % _FP_W_TYPE_SIZE; \ |
| 80 | _FP_FRAC_SRL_8_up = _FP_W_TYPE_SIZE - _FP_FRAC_SRL_8_down; \ |
| 81 | if (!_FP_FRAC_SRL_8_down) \ |
| 82 | for (_FP_FRAC_SRL_8_i = 0; \ |
| 83 | _FP_FRAC_SRL_8_i <= 7-_FP_FRAC_SRL_8_skip; \ |
| 84 | ++_FP_FRAC_SRL_8_i) \ |
| 85 | X##_f[_FP_FRAC_SRL_8_i] \ |
| 86 | = X##_f[_FP_FRAC_SRL_8_i+_FP_FRAC_SRL_8_skip]; \ |
| 87 | else \ |
| 88 | { \ |
| 89 | for (_FP_FRAC_SRL_8_i = 0; \ |
| 90 | _FP_FRAC_SRL_8_i < 7-_FP_FRAC_SRL_8_skip; \ |
| 91 | ++_FP_FRAC_SRL_8_i) \ |
| 92 | X##_f[_FP_FRAC_SRL_8_i] \ |
| 93 | = ((X##_f[_FP_FRAC_SRL_8_i+_FP_FRAC_SRL_8_skip] \ |
| 94 | >> _FP_FRAC_SRL_8_down) \ |
| 95 | | (X##_f[_FP_FRAC_SRL_8_i+_FP_FRAC_SRL_8_skip+1] \ |
| 96 | << _FP_FRAC_SRL_8_up)); \ |
| 97 | X##_f[_FP_FRAC_SRL_8_i++] = X##_f[7] >> _FP_FRAC_SRL_8_down; \ |
| 98 | } \ |
| 99 | for (; _FP_FRAC_SRL_8_i < 8; ++_FP_FRAC_SRL_8_i) \ |
| 100 | X##_f[_FP_FRAC_SRL_8_i] = 0; \ |
| 101 | } \ |
| 102 | while (0) |
| 103 | |
| 104 | |
| 105 | /* Right shift with sticky-lsb. |
| 106 | What this actually means is that we do a standard right-shift, |
| 107 | but that if any of the bits that fall off the right hand side |
| 108 | were one then we always set the LSbit. */ |
| 109 | #define _FP_FRAC_SRS_8(X, N, size) \ |
| 110 | do \ |
| 111 | { \ |
| 112 | _FP_I_TYPE _FP_FRAC_SRS_8_up, _FP_FRAC_SRS_8_down; \ |
| 113 | _FP_I_TYPE _FP_FRAC_SRS_8_skip, _FP_FRAC_SRS_8_i; \ |
| 114 | _FP_W_TYPE _FP_FRAC_SRS_8_s; \ |
| 115 | _FP_FRAC_SRS_8_skip = (N) / _FP_W_TYPE_SIZE; \ |
| 116 | _FP_FRAC_SRS_8_down = (N) % _FP_W_TYPE_SIZE; \ |
| 117 | _FP_FRAC_SRS_8_up = _FP_W_TYPE_SIZE - _FP_FRAC_SRS_8_down; \ |
| 118 | for (_FP_FRAC_SRS_8_s = _FP_FRAC_SRS_8_i = 0; \ |
| 119 | _FP_FRAC_SRS_8_i < _FP_FRAC_SRS_8_skip; \ |
| 120 | ++_FP_FRAC_SRS_8_i) \ |
| 121 | _FP_FRAC_SRS_8_s |= X##_f[_FP_FRAC_SRS_8_i]; \ |
| 122 | if (!_FP_FRAC_SRS_8_down) \ |
| 123 | for (_FP_FRAC_SRS_8_i = 0; \ |
| 124 | _FP_FRAC_SRS_8_i <= 7-_FP_FRAC_SRS_8_skip; \ |
| 125 | ++_FP_FRAC_SRS_8_i) \ |
| 126 | X##_f[_FP_FRAC_SRS_8_i] \ |
| 127 | = X##_f[_FP_FRAC_SRS_8_i+_FP_FRAC_SRS_8_skip]; \ |
| 128 | else \ |
| 129 | { \ |
| 130 | _FP_FRAC_SRS_8_s \ |
| 131 | |= X##_f[_FP_FRAC_SRS_8_i] << _FP_FRAC_SRS_8_up; \ |
| 132 | for (_FP_FRAC_SRS_8_i = 0; \ |
| 133 | _FP_FRAC_SRS_8_i < 7-_FP_FRAC_SRS_8_skip; \ |
| 134 | ++_FP_FRAC_SRS_8_i) \ |
| 135 | X##_f[_FP_FRAC_SRS_8_i] \ |
| 136 | = ((X##_f[_FP_FRAC_SRS_8_i+_FP_FRAC_SRS_8_skip] \ |
| 137 | >> _FP_FRAC_SRS_8_down) \ |
| 138 | | (X##_f[_FP_FRAC_SRS_8_i+_FP_FRAC_SRS_8_skip+1] \ |
| 139 | << _FP_FRAC_SRS_8_up)); \ |
| 140 | X##_f[_FP_FRAC_SRS_8_i++] = X##_f[7] >> _FP_FRAC_SRS_8_down; \ |
| 141 | } \ |
| 142 | for (; _FP_FRAC_SRS_8_i < 8; ++_FP_FRAC_SRS_8_i) \ |
| 143 | X##_f[_FP_FRAC_SRS_8_i] = 0; \ |
| 144 | /* Don't fix the LSB until the very end when we're sure f[0] is \ |
| 145 | stable. */ \ |
| 146 | X##_f[0] |= (_FP_FRAC_SRS_8_s != 0); \ |
| 147 | } \ |
| 148 | while (0) |
| 149 | |
| 150 | #endif /* !SOFT_FP_OP_8_H */ |