| /* Software floating-point emulation. |
| Basic eight-word fraction declaration and manipulation. |
| Copyright (C) 1997,1998,1999,2006 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Richard Henderson (rth@cygnus.com), |
| Jakub Jelinek (jj@ultra.linux.cz) and |
| Peter Maydell (pmaydell@chiark.greenend.org.uk). |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| In addition to the permissions in the GNU Lesser General Public |
| License, the Free Software Foundation gives you unlimited |
| permission to link the compiled version of this file into |
| combinations with other programs, and to distribute those |
| combinations without any restriction coming from the use of this |
| file. (The Lesser General Public License restrictions do apply in |
| other respects; for example, they cover modification of the file, |
| and distribution when not linked into a combine executable.) |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, write to the Free |
| Software Foundation, 51 Franklin Street, Fifth Floor, Boston, |
| MA 02110-1301, USA. */ |
| |
| /* We need just a few things from here for op-4, if we ever need some |
| other macros, they can be added. */ |
| #define _FP_FRAC_DECL_8(X) _FP_W_TYPE X##_f[8] |
| #define _FP_FRAC_HIGH_8(X) (X##_f[7]) |
| #define _FP_FRAC_LOW_8(X) (X##_f[0]) |
| #define _FP_FRAC_WORD_8(X,w) (X##_f[w]) |
| |
| #define _FP_FRAC_SLL_8(X,N) \ |
| do { \ |
| _FP_I_TYPE _up, _down, _skip, _i; \ |
| _skip = (N) / _FP_W_TYPE_SIZE; \ |
| _up = (N) % _FP_W_TYPE_SIZE; \ |
| _down = _FP_W_TYPE_SIZE - _up; \ |
| if (!_up) \ |
| for (_i = 7; _i >= _skip; --_i) \ |
| X##_f[_i] = X##_f[_i-_skip]; \ |
| else \ |
| { \ |
| for (_i = 7; _i > _skip; --_i) \ |
| X##_f[_i] = X##_f[_i-_skip] << _up \ |
| | X##_f[_i-_skip-1] >> _down; \ |
| X##_f[_i--] = X##_f[0] << _up; \ |
| } \ |
| for (; _i >= 0; --_i) \ |
| X##_f[_i] = 0; \ |
| } while (0) |
| |
| #define _FP_FRAC_SRL_8(X,N) \ |
| do { \ |
| _FP_I_TYPE _up, _down, _skip, _i; \ |
| _skip = (N) / _FP_W_TYPE_SIZE; \ |
| _down = (N) % _FP_W_TYPE_SIZE; \ |
| _up = _FP_W_TYPE_SIZE - _down; \ |
| if (!_down) \ |
| for (_i = 0; _i <= 7-_skip; ++_i) \ |
| X##_f[_i] = X##_f[_i+_skip]; \ |
| else \ |
| { \ |
| for (_i = 0; _i < 7-_skip; ++_i) \ |
| X##_f[_i] = X##_f[_i+_skip] >> _down \ |
| | X##_f[_i+_skip+1] << _up; \ |
| X##_f[_i++] = X##_f[7] >> _down; \ |
| } \ |
| for (; _i < 8; ++_i) \ |
| X##_f[_i] = 0; \ |
| } while (0) |
| |
| |
| /* Right shift with sticky-lsb. |
| * What this actually means is that we do a standard right-shift, |
| * but that if any of the bits that fall off the right hand side |
| * were one then we always set the LSbit. |
| */ |
| #define _FP_FRAC_SRS_8(X,N,size) \ |
| do { \ |
| _FP_I_TYPE _up, _down, _skip, _i; \ |
| _FP_W_TYPE _s; \ |
| _skip = (N) / _FP_W_TYPE_SIZE; \ |
| _down = (N) % _FP_W_TYPE_SIZE; \ |
| _up = _FP_W_TYPE_SIZE - _down; \ |
| for (_s = _i = 0; _i < _skip; ++_i) \ |
| _s |= X##_f[_i]; \ |
| if (!_down) \ |
| for (_i = 0; _i <= 7-_skip; ++_i) \ |
| X##_f[_i] = X##_f[_i+_skip]; \ |
| else \ |
| { \ |
| _s |= X##_f[_i] << _up; \ |
| for (_i = 0; _i < 7-_skip; ++_i) \ |
| X##_f[_i] = X##_f[_i+_skip] >> _down \ |
| | X##_f[_i+_skip+1] << _up; \ |
| X##_f[_i++] = X##_f[7] >> _down; \ |
| } \ |
| for (; _i < 8; ++_i) \ |
| X##_f[_i] = 0; \ |
| /* don't fix the LSB until the very end when we're sure f[0] is stable */ \ |
| X##_f[0] |= (_s != 0); \ |
| } while (0) |
| |
