0,0 → 1,111 |
/* 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) |
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