Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* Software floating-point emulation. |
| 2 | Basic four-word fraction declaration and manipulation. |
| 3 | Copyright (C) 1997,1998,1999 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), |
| 7 | David S. Miller (davem@redhat.com) and |
| 8 | Peter Maydell (pmaydell@chiark.greenend.org.uk). |
| 9 | |
| 10 | The GNU C Library is free software; you can redistribute it and/or |
| 11 | modify it under the terms of the GNU Library General Public License as |
| 12 | published by the Free Software Foundation; either version 2 of the |
| 13 | License, or (at your option) any later version. |
| 14 | |
| 15 | The GNU C Library is distributed in the hope that it will be useful, |
| 16 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 18 | Library General Public License for more details. |
| 19 | |
| 20 | You should have received a copy of the GNU Library General Public |
| 21 | License along with the GNU C Library; see the file COPYING.LIB. If |
| 22 | not, write to the Free Software Foundation, Inc., |
| 23 | 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| 24 | |
| 25 | #ifndef __MATH_EMU_OP_4_H__ |
| 26 | #define __MATH_EMU_OP_4_H__ |
| 27 | |
| 28 | #define _FP_FRAC_DECL_4(X) _FP_W_TYPE X##_f[4] |
| 29 | #define _FP_FRAC_COPY_4(D,S) \ |
| 30 | (D##_f[0] = S##_f[0], D##_f[1] = S##_f[1], \ |
| 31 | D##_f[2] = S##_f[2], D##_f[3] = S##_f[3]) |
| 32 | #define _FP_FRAC_SET_4(X,I) __FP_FRAC_SET_4(X, I) |
| 33 | #define _FP_FRAC_HIGH_4(X) (X##_f[3]) |
| 34 | #define _FP_FRAC_LOW_4(X) (X##_f[0]) |
| 35 | #define _FP_FRAC_WORD_4(X,w) (X##_f[w]) |
| 36 | |
| 37 | #define _FP_FRAC_SLL_4(X,N) \ |
| 38 | do { \ |
| 39 | _FP_I_TYPE _up, _down, _skip, _i; \ |
| 40 | _skip = (N) / _FP_W_TYPE_SIZE; \ |
| 41 | _up = (N) % _FP_W_TYPE_SIZE; \ |
| 42 | _down = _FP_W_TYPE_SIZE - _up; \ |
| 43 | if (!_up) \ |
| 44 | for (_i = 3; _i >= _skip; --_i) \ |
| 45 | X##_f[_i] = X##_f[_i-_skip]; \ |
| 46 | else \ |
| 47 | { \ |
| 48 | for (_i = 3; _i > _skip; --_i) \ |
| 49 | X##_f[_i] = X##_f[_i-_skip] << _up \ |
| 50 | | X##_f[_i-_skip-1] >> _down; \ |
| 51 | X##_f[_i--] = X##_f[0] << _up; \ |
| 52 | } \ |
| 53 | for (; _i >= 0; --_i) \ |
| 54 | X##_f[_i] = 0; \ |
| 55 | } while (0) |
| 56 | |
| 57 | /* This one was broken too */ |
| 58 | #define _FP_FRAC_SRL_4(X,N) \ |
| 59 | do { \ |
| 60 | _FP_I_TYPE _up, _down, _skip, _i; \ |
| 61 | _skip = (N) / _FP_W_TYPE_SIZE; \ |
| 62 | _down = (N) % _FP_W_TYPE_SIZE; \ |
| 63 | _up = _FP_W_TYPE_SIZE - _down; \ |
| 64 | if (!_down) \ |
| 65 | for (_i = 0; _i <= 3-_skip; ++_i) \ |
| 66 | X##_f[_i] = X##_f[_i+_skip]; \ |
| 67 | else \ |
| 68 | { \ |
| 69 | for (_i = 0; _i < 3-_skip; ++_i) \ |
| 70 | X##_f[_i] = X##_f[_i+_skip] >> _down \ |
| 71 | | X##_f[_i+_skip+1] << _up; \ |
| 72 | X##_f[_i++] = X##_f[3] >> _down; \ |
| 73 | } \ |
| 74 | for (; _i < 4; ++_i) \ |
| 75 | X##_f[_i] = 0; \ |
| 76 | } while (0) |
| 77 | |
| 78 | |
| 79 | /* Right shift with sticky-lsb. |
| 80 | * What this actually means is that we do a standard right-shift, |
| 81 | * but that if any of the bits that fall off the right hand side |
| 82 | * were one then we always set the LSbit. |
| 83 | */ |
| 84 | #define _FP_FRAC_SRS_4(X,N,size) \ |
| 85 | do { \ |
| 86 | _FP_I_TYPE _up, _down, _skip, _i; \ |
| 87 | _FP_W_TYPE _s; \ |
| 88 | _skip = (N) / _FP_W_TYPE_SIZE; \ |
| 89 | _down = (N) % _FP_W_TYPE_SIZE; \ |
| 90 | _up = _FP_W_TYPE_SIZE - _down; \ |
| 91 | for (_s = _i = 0; _i < _skip; ++_i) \ |
| 92 | _s |= X##_f[_i]; \ |
| 93 | _s |= X##_f[_i] << _up; \ |
| 94 | /* s is now != 0 if we want to set the LSbit */ \ |
| 95 | if (!_down) \ |
| 96 | for (_i = 0; _i <= 3-_skip; ++_i) \ |
| 97 | X##_f[_i] = X##_f[_i+_skip]; \ |
| 98 | else \ |
| 99 | { \ |
| 100 | for (_i = 0; _i < 3-_skip; ++_i) \ |
| 101 | X##_f[_i] = X##_f[_i+_skip] >> _down \ |
| 102 | | X##_f[_i+_skip+1] << _up; \ |
| 103 | X##_f[_i++] = X##_f[3] >> _down; \ |
| 104 | } \ |
| 105 | for (; _i < 4; ++_i) \ |
| 106 | X##_f[_i] = 0; \ |
| 107 | /* don't fix the LSB until the very end when we're sure f[0] is stable */ \ |
| 108 | X##_f[0] |= (_s != 0); \ |
| 109 | } while (0) |
| 110 | |
| 111 | #define _FP_FRAC_ADD_4(R,X,Y) \ |
| 112 | __FP_FRAC_ADD_4(R##_f[3], R##_f[2], R##_f[1], R##_f[0], \ |
| 113 | X##_f[3], X##_f[2], X##_f[1], X##_f[0], \ |
| 114 | Y##_f[3], Y##_f[2], Y##_f[1], Y##_f[0]) |
| 115 | |
| 116 | #define _FP_FRAC_SUB_4(R,X,Y) \ |
| 117 | __FP_FRAC_SUB_4(R##_f[3], R##_f[2], R##_f[1], R##_f[0], \ |
| 118 | X##_f[3], X##_f[2], X##_f[1], X##_f[0], \ |
| 119 | Y##_f[3], Y##_f[2], Y##_f[1], Y##_f[0]) |
| 120 | |
| 121 | #define _FP_FRAC_DEC_4(X,Y) \ |
| 122 | __FP_FRAC_DEC_4(X##_f[3], X##_f[2], X##_f[1], X##_f[0], \ |
| 123 | Y##_f[3], Y##_f[2], Y##_f[1], Y##_f[0]) |
| 124 | |
| 125 | #define _FP_FRAC_ADDI_4(X,I) \ |
| 126 | __FP_FRAC_ADDI_4(X##_f[3], X##_f[2], X##_f[1], X##_f[0], I) |
| 127 | |
| 128 | #define _FP_ZEROFRAC_4 0,0,0,0 |
| 129 | #define _FP_MINFRAC_4 0,0,0,1 |
| 130 | #define _FP_MAXFRAC_4 (~(_FP_WS_TYPE)0), (~(_FP_WS_TYPE)0), (~(_FP_WS_TYPE)0), (~(_FP_WS_TYPE)0) |
| 131 | |
| 132 | #define _FP_FRAC_ZEROP_4(X) ((X##_f[0] | X##_f[1] | X##_f[2] | X##_f[3]) == 0) |
| 133 | #define _FP_FRAC_NEGP_4(X) ((_FP_WS_TYPE)X##_f[3] < 0) |
| 134 | #define _FP_FRAC_OVERP_4(fs,X) (_FP_FRAC_HIGH_##fs(X) & _FP_OVERFLOW_##fs) |
| 135 | #define _FP_FRAC_CLEAR_OVERP_4(fs,X) (_FP_FRAC_HIGH_##fs(X) &= ~_FP_OVERFLOW_##fs) |
| 136 | |
| 137 | #define _FP_FRAC_EQ_4(X,Y) \ |
| 138 | (X##_f[0] == Y##_f[0] && X##_f[1] == Y##_f[1] \ |
| 139 | && X##_f[2] == Y##_f[2] && X##_f[3] == Y##_f[3]) |
| 140 | |
| 141 | #define _FP_FRAC_GT_4(X,Y) \ |
| 142 | (X##_f[3] > Y##_f[3] || \ |
| 143 | (X##_f[3] == Y##_f[3] && (X##_f[2] > Y##_f[2] || \ |
| 144 | (X##_f[2] == Y##_f[2] && (X##_f[1] > Y##_f[1] || \ |
| 145 | (X##_f[1] == Y##_f[1] && X##_f[0] > Y##_f[0]) \ |
| 146 | )) \ |
| 147 | )) \ |
| 148 | ) |
| 149 | |
| 150 | #define _FP_FRAC_GE_4(X,Y) \ |
| 151 | (X##_f[3] > Y##_f[3] || \ |
| 152 | (X##_f[3] == Y##_f[3] && (X##_f[2] > Y##_f[2] || \ |
| 153 | (X##_f[2] == Y##_f[2] && (X##_f[1] > Y##_f[1] || \ |
| 154 | (X##_f[1] == Y##_f[1] && X##_f[0] >= Y##_f[0]) \ |
| 155 | )) \ |
| 156 | )) \ |
| 157 | ) |
| 158 | |
| 159 | |
| 160 | #define _FP_FRAC_CLZ_4(R,X) \ |
| 161 | do { \ |
| 162 | if (X##_f[3]) \ |
| 163 | { \ |
| 164 | __FP_CLZ(R,X##_f[3]); \ |
| 165 | } \ |
| 166 | else if (X##_f[2]) \ |
| 167 | { \ |
| 168 | __FP_CLZ(R,X##_f[2]); \ |
| 169 | R += _FP_W_TYPE_SIZE; \ |
| 170 | } \ |
| 171 | else if (X##_f[1]) \ |
| 172 | { \ |
| 173 | __FP_CLZ(R,X##_f[2]); \ |
| 174 | R += _FP_W_TYPE_SIZE*2; \ |
| 175 | } \ |
| 176 | else \ |
| 177 | { \ |
| 178 | __FP_CLZ(R,X##_f[0]); \ |
| 179 | R += _FP_W_TYPE_SIZE*3; \ |
| 180 | } \ |
| 181 | } while(0) |
| 182 | |
| 183 | |
| 184 | #define _FP_UNPACK_RAW_4(fs, X, val) \ |
| 185 | do { \ |
| 186 | union _FP_UNION_##fs _flo; _flo.flt = (val); \ |
| 187 | X##_f[0] = _flo.bits.frac0; \ |
| 188 | X##_f[1] = _flo.bits.frac1; \ |
| 189 | X##_f[2] = _flo.bits.frac2; \ |
| 190 | X##_f[3] = _flo.bits.frac3; \ |
| 191 | X##_e = _flo.bits.exp; \ |
| 192 | X##_s = _flo.bits.sign; \ |
| 193 | } while (0) |
| 194 | |
| 195 | #define _FP_UNPACK_RAW_4_P(fs, X, val) \ |
| 196 | do { \ |
| 197 | union _FP_UNION_##fs *_flo = \ |
| 198 | (union _FP_UNION_##fs *)(val); \ |
| 199 | \ |
| 200 | X##_f[0] = _flo->bits.frac0; \ |
| 201 | X##_f[1] = _flo->bits.frac1; \ |
| 202 | X##_f[2] = _flo->bits.frac2; \ |
| 203 | X##_f[3] = _flo->bits.frac3; \ |
| 204 | X##_e = _flo->bits.exp; \ |
| 205 | X##_s = _flo->bits.sign; \ |
| 206 | } while (0) |
| 207 | |
| 208 | #define _FP_PACK_RAW_4(fs, val, X) \ |
| 209 | do { \ |
| 210 | union _FP_UNION_##fs _flo; \ |
| 211 | _flo.bits.frac0 = X##_f[0]; \ |
| 212 | _flo.bits.frac1 = X##_f[1]; \ |
| 213 | _flo.bits.frac2 = X##_f[2]; \ |
| 214 | _flo.bits.frac3 = X##_f[3]; \ |
| 215 | _flo.bits.exp = X##_e; \ |
| 216 | _flo.bits.sign = X##_s; \ |
| 217 | (val) = _flo.flt; \ |
| 218 | } while (0) |
| 219 | |
| 220 | #define _FP_PACK_RAW_4_P(fs, val, X) \ |
| 221 | do { \ |
| 222 | union _FP_UNION_##fs *_flo = \ |
| 223 | (union _FP_UNION_##fs *)(val); \ |
| 224 | \ |
| 225 | _flo->bits.frac0 = X##_f[0]; \ |
| 226 | _flo->bits.frac1 = X##_f[1]; \ |
| 227 | _flo->bits.frac2 = X##_f[2]; \ |
| 228 | _flo->bits.frac3 = X##_f[3]; \ |
| 229 | _flo->bits.exp = X##_e; \ |
| 230 | _flo->bits.sign = X##_s; \ |
| 231 | } while (0) |
| 232 | |
| 233 | /* |
| 234 | * Multiplication algorithms: |
| 235 | */ |
| 236 | |
| 237 | /* Given a 1W * 1W => 2W primitive, do the extended multiplication. */ |
| 238 | |
| 239 | #define _FP_MUL_MEAT_4_wide(wfracbits, R, X, Y, doit) \ |
| 240 | do { \ |
| 241 | _FP_FRAC_DECL_8(_z); _FP_FRAC_DECL_2(_b); _FP_FRAC_DECL_2(_c); \ |
| 242 | _FP_FRAC_DECL_2(_d); _FP_FRAC_DECL_2(_e); _FP_FRAC_DECL_2(_f); \ |
| 243 | \ |
| 244 | doit(_FP_FRAC_WORD_8(_z,1), _FP_FRAC_WORD_8(_z,0), X##_f[0], Y##_f[0]); \ |
| 245 | doit(_b_f1, _b_f0, X##_f[0], Y##_f[1]); \ |
| 246 | doit(_c_f1, _c_f0, X##_f[1], Y##_f[0]); \ |
| 247 | doit(_d_f1, _d_f0, X##_f[1], Y##_f[1]); \ |
| 248 | doit(_e_f1, _e_f0, X##_f[0], Y##_f[2]); \ |
| 249 | doit(_f_f1, _f_f0, X##_f[2], Y##_f[0]); \ |
| 250 | __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,3),_FP_FRAC_WORD_8(_z,2), \ |
| 251 | _FP_FRAC_WORD_8(_z,1), 0,_b_f1,_b_f0, \ |
| 252 | 0,0,_FP_FRAC_WORD_8(_z,1)); \ |
| 253 | __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,3),_FP_FRAC_WORD_8(_z,2), \ |
| 254 | _FP_FRAC_WORD_8(_z,1), 0,_c_f1,_c_f0, \ |
| 255 | _FP_FRAC_WORD_8(_z,3),_FP_FRAC_WORD_8(_z,2), \ |
| 256 | _FP_FRAC_WORD_8(_z,1)); \ |
| 257 | __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,4),_FP_FRAC_WORD_8(_z,3), \ |
| 258 | _FP_FRAC_WORD_8(_z,2), 0,_d_f1,_d_f0, \ |
| 259 | 0,_FP_FRAC_WORD_8(_z,3),_FP_FRAC_WORD_8(_z,2)); \ |
| 260 | __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,4),_FP_FRAC_WORD_8(_z,3), \ |
| 261 | _FP_FRAC_WORD_8(_z,2), 0,_e_f1,_e_f0, \ |
| 262 | _FP_FRAC_WORD_8(_z,4),_FP_FRAC_WORD_8(_z,3), \ |
| 263 | _FP_FRAC_WORD_8(_z,2)); \ |
| 264 | __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,4),_FP_FRAC_WORD_8(_z,3), \ |
| 265 | _FP_FRAC_WORD_8(_z,2), 0,_f_f1,_f_f0, \ |
| 266 | _FP_FRAC_WORD_8(_z,4),_FP_FRAC_WORD_8(_z,3), \ |
| 267 | _FP_FRAC_WORD_8(_z,2)); \ |
| 268 | doit(_b_f1, _b_f0, X##_f[0], Y##_f[3]); \ |
| 269 | doit(_c_f1, _c_f0, X##_f[3], Y##_f[0]); \ |
| 270 | doit(_d_f1, _d_f0, X##_f[1], Y##_f[2]); \ |
| 271 | doit(_e_f1, _e_f0, X##_f[2], Y##_f[1]); \ |
| 272 | __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4), \ |
| 273 | _FP_FRAC_WORD_8(_z,3), 0,_b_f1,_b_f0, \ |
| 274 | 0,_FP_FRAC_WORD_8(_z,4),_FP_FRAC_WORD_8(_z,3)); \ |
| 275 | __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4), \ |
| 276 | _FP_FRAC_WORD_8(_z,3), 0,_c_f1,_c_f0, \ |
| 277 | _FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4), \ |
| 278 | _FP_FRAC_WORD_8(_z,3)); \ |
| 279 | __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4), \ |
| 280 | _FP_FRAC_WORD_8(_z,3), 0,_d_f1,_d_f0, \ |
| 281 | _FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4), \ |
| 282 | _FP_FRAC_WORD_8(_z,3)); \ |
| 283 | __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4), \ |
| 284 | _FP_FRAC_WORD_8(_z,3), 0,_e_f1,_e_f0, \ |
| 285 | _FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4), \ |
| 286 | _FP_FRAC_WORD_8(_z,3)); \ |
| 287 | doit(_b_f1, _b_f0, X##_f[2], Y##_f[2]); \ |
| 288 | doit(_c_f1, _c_f0, X##_f[1], Y##_f[3]); \ |
| 289 | doit(_d_f1, _d_f0, X##_f[3], Y##_f[1]); \ |
| 290 | doit(_e_f1, _e_f0, X##_f[2], Y##_f[3]); \ |
| 291 | doit(_f_f1, _f_f0, X##_f[3], Y##_f[2]); \ |
| 292 | __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,6),_FP_FRAC_WORD_8(_z,5), \ |
| 293 | _FP_FRAC_WORD_8(_z,4), 0,_b_f1,_b_f0, \ |
| 294 | 0,_FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4)); \ |
| 295 | __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,6),_FP_FRAC_WORD_8(_z,5), \ |
| 296 | _FP_FRAC_WORD_8(_z,4), 0,_c_f1,_c_f0, \ |
| 297 | _FP_FRAC_WORD_8(_z,6),_FP_FRAC_WORD_8(_z,5), \ |
| 298 | _FP_FRAC_WORD_8(_z,4)); \ |
| 299 | __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,6),_FP_FRAC_WORD_8(_z,5), \ |
| 300 | _FP_FRAC_WORD_8(_z,4), 0,_d_f1,_d_f0, \ |
| 301 | _FP_FRAC_WORD_8(_z,6),_FP_FRAC_WORD_8(_z,5), \ |
| 302 | _FP_FRAC_WORD_8(_z,4)); \ |
| 303 | __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,7),_FP_FRAC_WORD_8(_z,6), \ |
| 304 | _FP_FRAC_WORD_8(_z,5), 0,_e_f1,_e_f0, \ |
| 305 | 0,_FP_FRAC_WORD_8(_z,6),_FP_FRAC_WORD_8(_z,5)); \ |
| 306 | __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,7),_FP_FRAC_WORD_8(_z,6), \ |
| 307 | _FP_FRAC_WORD_8(_z,5), 0,_f_f1,_f_f0, \ |
| 308 | _FP_FRAC_WORD_8(_z,7),_FP_FRAC_WORD_8(_z,6), \ |
| 309 | _FP_FRAC_WORD_8(_z,5)); \ |
| 310 | doit(_b_f1, _b_f0, X##_f[3], Y##_f[3]); \ |
| 311 | __FP_FRAC_ADD_2(_FP_FRAC_WORD_8(_z,7),_FP_FRAC_WORD_8(_z,6), \ |
| 312 | _b_f1,_b_f0, \ |
| 313 | _FP_FRAC_WORD_8(_z,7),_FP_FRAC_WORD_8(_z,6)); \ |
| 314 | \ |
| 315 | /* Normalize since we know where the msb of the multiplicands \ |
| 316 | were (bit B), we know that the msb of the of the product is \ |
| 317 | at either 2B or 2B-1. */ \ |
| 318 | _FP_FRAC_SRS_8(_z, wfracbits-1, 2*wfracbits); \ |
| 319 | __FP_FRAC_SET_4(R, _FP_FRAC_WORD_8(_z,3), _FP_FRAC_WORD_8(_z,2), \ |
| 320 | _FP_FRAC_WORD_8(_z,1), _FP_FRAC_WORD_8(_z,0)); \ |
| 321 | } while (0) |
| 322 | |
| 323 | #define _FP_MUL_MEAT_4_gmp(wfracbits, R, X, Y) \ |
| 324 | do { \ |
| 325 | _FP_FRAC_DECL_8(_z); \ |
| 326 | \ |
| 327 | mpn_mul_n(_z_f, _x_f, _y_f, 4); \ |
| 328 | \ |
| 329 | /* Normalize since we know where the msb of the multiplicands \ |
| 330 | were (bit B), we know that the msb of the of the product is \ |
| 331 | at either 2B or 2B-1. */ \ |
| 332 | _FP_FRAC_SRS_8(_z, wfracbits-1, 2*wfracbits); \ |
| 333 | __FP_FRAC_SET_4(R, _FP_FRAC_WORD_8(_z,3), _FP_FRAC_WORD_8(_z,2), \ |
| 334 | _FP_FRAC_WORD_8(_z,1), _FP_FRAC_WORD_8(_z,0)); \ |
| 335 | } while (0) |
| 336 | |
| 337 | /* |
| 338 | * Helper utility for _FP_DIV_MEAT_4_udiv: |
| 339 | * pppp = m * nnn |
| 340 | */ |
| 341 | #define umul_ppppmnnn(p3,p2,p1,p0,m,n2,n1,n0) \ |
| 342 | do { \ |
| 343 | UWtype _t; \ |
| 344 | umul_ppmm(p1,p0,m,n0); \ |
| 345 | umul_ppmm(p2,_t,m,n1); \ |
| 346 | __FP_FRAC_ADDI_2(p2,p1,_t); \ |
| 347 | umul_ppmm(p3,_t,m,n2); \ |
| 348 | __FP_FRAC_ADDI_2(p3,p2,_t); \ |
| 349 | } while (0) |
| 350 | |
| 351 | /* |
| 352 | * Division algorithms: |
| 353 | */ |
| 354 | |
| 355 | #define _FP_DIV_MEAT_4_udiv(fs, R, X, Y) \ |
| 356 | do { \ |
| 357 | int _i; \ |
| 358 | _FP_FRAC_DECL_4(_n); _FP_FRAC_DECL_4(_m); \ |
| 359 | _FP_FRAC_SET_4(_n, _FP_ZEROFRAC_4); \ |
| 360 | if (_FP_FRAC_GT_4(X, Y)) \ |
| 361 | { \ |
| 362 | _n_f[3] = X##_f[0] << (_FP_W_TYPE_SIZE - 1); \ |
| 363 | _FP_FRAC_SRL_4(X, 1); \ |
| 364 | } \ |
| 365 | else \ |
| 366 | R##_e--; \ |
| 367 | \ |
| 368 | /* Normalize, i.e. make the most significant bit of the \ |
| 369 | denominator set. */ \ |
| 370 | _FP_FRAC_SLL_4(Y, _FP_WFRACXBITS_##fs); \ |
| 371 | \ |
| 372 | for (_i = 3; ; _i--) \ |
| 373 | { \ |
| 374 | if (X##_f[3] == Y##_f[3]) \ |
| 375 | { \ |
| 376 | /* This is a special case, not an optimization \ |
| 377 | (X##_f[3]/Y##_f[3] would not fit into UWtype). \ |
| 378 | As X## is guaranteed to be < Y, R##_f[_i] can be either \ |
| 379 | (UWtype)-1 or (UWtype)-2. */ \ |
| 380 | R##_f[_i] = -1; \ |
| 381 | if (!_i) \ |
| 382 | break; \ |
| 383 | __FP_FRAC_SUB_4(X##_f[3], X##_f[2], X##_f[1], X##_f[0], \ |
| 384 | Y##_f[2], Y##_f[1], Y##_f[0], 0, \ |
| 385 | X##_f[2], X##_f[1], X##_f[0], _n_f[_i]); \ |
| 386 | _FP_FRAC_SUB_4(X, Y, X); \ |
| 387 | if (X##_f[3] > Y##_f[3]) \ |
| 388 | { \ |
| 389 | R##_f[_i] = -2; \ |
| 390 | _FP_FRAC_ADD_4(X, Y, X); \ |
| 391 | } \ |
| 392 | } \ |
| 393 | else \ |
| 394 | { \ |
| 395 | udiv_qrnnd(R##_f[_i], X##_f[3], X##_f[3], X##_f[2], Y##_f[3]); \ |
| 396 | umul_ppppmnnn(_m_f[3], _m_f[2], _m_f[1], _m_f[0], \ |
| 397 | R##_f[_i], Y##_f[2], Y##_f[1], Y##_f[0]); \ |
| 398 | X##_f[2] = X##_f[1]; \ |
| 399 | X##_f[1] = X##_f[0]; \ |
| 400 | X##_f[0] = _n_f[_i]; \ |
| 401 | if (_FP_FRAC_GT_4(_m, X)) \ |
| 402 | { \ |
| 403 | R##_f[_i]--; \ |
| 404 | _FP_FRAC_ADD_4(X, Y, X); \ |
| 405 | if (_FP_FRAC_GE_4(X, Y) && _FP_FRAC_GT_4(_m, X)) \ |
| 406 | { \ |
| 407 | R##_f[_i]--; \ |
| 408 | _FP_FRAC_ADD_4(X, Y, X); \ |
| 409 | } \ |
| 410 | } \ |
| 411 | _FP_FRAC_DEC_4(X, _m); \ |
| 412 | if (!_i) \ |
| 413 | { \ |
| 414 | if (!_FP_FRAC_EQ_4(X, _m)) \ |
| 415 | R##_f[0] |= _FP_WORK_STICKY; \ |
| 416 | break; \ |
| 417 | } \ |
| 418 | } \ |
| 419 | } \ |
| 420 | } while (0) |
| 421 | |
| 422 | |
| 423 | /* |
| 424 | * Square root algorithms: |
| 425 | * We have just one right now, maybe Newton approximation |
| 426 | * should be added for those machines where division is fast. |
| 427 | */ |
| 428 | |
| 429 | #define _FP_SQRT_MEAT_4(R, S, T, X, q) \ |
| 430 | do { \ |
| 431 | while (q) \ |
| 432 | { \ |
| 433 | T##_f[3] = S##_f[3] + q; \ |
| 434 | if (T##_f[3] <= X##_f[3]) \ |
| 435 | { \ |
| 436 | S##_f[3] = T##_f[3] + q; \ |
| 437 | X##_f[3] -= T##_f[3]; \ |
| 438 | R##_f[3] += q; \ |
| 439 | } \ |
| 440 | _FP_FRAC_SLL_4(X, 1); \ |
| 441 | q >>= 1; \ |
| 442 | } \ |
| 443 | q = (_FP_W_TYPE)1 << (_FP_W_TYPE_SIZE - 1); \ |
| 444 | while (q) \ |
| 445 | { \ |
| 446 | T##_f[2] = S##_f[2] + q; \ |
| 447 | T##_f[3] = S##_f[3]; \ |
| 448 | if (T##_f[3] < X##_f[3] || \ |
| 449 | (T##_f[3] == X##_f[3] && T##_f[2] <= X##_f[2])) \ |
| 450 | { \ |
| 451 | S##_f[2] = T##_f[2] + q; \ |
| 452 | S##_f[3] += (T##_f[2] > S##_f[2]); \ |
| 453 | __FP_FRAC_DEC_2(X##_f[3], X##_f[2], \ |
| 454 | T##_f[3], T##_f[2]); \ |
| 455 | R##_f[2] += q; \ |
| 456 | } \ |
| 457 | _FP_FRAC_SLL_4(X, 1); \ |
| 458 | q >>= 1; \ |
| 459 | } \ |
| 460 | q = (_FP_W_TYPE)1 << (_FP_W_TYPE_SIZE - 1); \ |
| 461 | while (q) \ |
| 462 | { \ |
| 463 | T##_f[1] = S##_f[1] + q; \ |
| 464 | T##_f[2] = S##_f[2]; \ |
| 465 | T##_f[3] = S##_f[3]; \ |
| 466 | if (T##_f[3] < X##_f[3] || \ |
| 467 | (T##_f[3] == X##_f[3] && (T##_f[2] < X##_f[2] || \ |
| 468 | (T##_f[2] == X##_f[2] && T##_f[1] <= X##_f[1])))) \ |
| 469 | { \ |
| 470 | S##_f[1] = T##_f[1] + q; \ |
| 471 | S##_f[2] += (T##_f[1] > S##_f[1]); \ |
| 472 | S##_f[3] += (T##_f[2] > S##_f[2]); \ |
| 473 | __FP_FRAC_DEC_3(X##_f[3], X##_f[2], X##_f[1], \ |
| 474 | T##_f[3], T##_f[2], T##_f[1]); \ |
| 475 | R##_f[1] += q; \ |
| 476 | } \ |
| 477 | _FP_FRAC_SLL_4(X, 1); \ |
| 478 | q >>= 1; \ |
| 479 | } \ |
| 480 | q = (_FP_W_TYPE)1 << (_FP_W_TYPE_SIZE - 1); \ |
| 481 | while (q != _FP_WORK_ROUND) \ |
| 482 | { \ |
| 483 | T##_f[0] = S##_f[0] + q; \ |
| 484 | T##_f[1] = S##_f[1]; \ |
| 485 | T##_f[2] = S##_f[2]; \ |
| 486 | T##_f[3] = S##_f[3]; \ |
| 487 | if (_FP_FRAC_GE_4(X,T)) \ |
| 488 | { \ |
| 489 | S##_f[0] = T##_f[0] + q; \ |
| 490 | S##_f[1] += (T##_f[0] > S##_f[0]); \ |
| 491 | S##_f[2] += (T##_f[1] > S##_f[1]); \ |
| 492 | S##_f[3] += (T##_f[2] > S##_f[2]); \ |
| 493 | _FP_FRAC_DEC_4(X, T); \ |
| 494 | R##_f[0] += q; \ |
| 495 | } \ |
| 496 | _FP_FRAC_SLL_4(X, 1); \ |
| 497 | q >>= 1; \ |
| 498 | } \ |
| 499 | if (!_FP_FRAC_ZEROP_4(X)) \ |
| 500 | { \ |
| 501 | if (_FP_FRAC_GT_4(X,S)) \ |
| 502 | R##_f[0] |= _FP_WORK_ROUND; \ |
| 503 | R##_f[0] |= _FP_WORK_STICKY; \ |
| 504 | } \ |
| 505 | } while (0) |
| 506 | |
| 507 | |
| 508 | /* |
| 509 | * Internals |
| 510 | */ |
| 511 | |
| 512 | #define __FP_FRAC_SET_4(X,I3,I2,I1,I0) \ |
| 513 | (X##_f[3] = I3, X##_f[2] = I2, X##_f[1] = I1, X##_f[0] = I0) |
| 514 | |
| 515 | #ifndef __FP_FRAC_ADD_3 |
| 516 | #define __FP_FRAC_ADD_3(r2,r1,r0,x2,x1,x0,y2,y1,y0) \ |
| 517 | do { \ |
| 518 | int _c1, _c2; \ |
| 519 | r0 = x0 + y0; \ |
| 520 | _c1 = r0 < x0; \ |
| 521 | r1 = x1 + y1; \ |
| 522 | _c2 = r1 < x1; \ |
| 523 | r1 += _c1; \ |
| 524 | _c2 |= r1 < _c1; \ |
| 525 | r2 = x2 + y2 + _c2; \ |
| 526 | } while (0) |
| 527 | #endif |
| 528 | |
| 529 | #ifndef __FP_FRAC_ADD_4 |
| 530 | #define __FP_FRAC_ADD_4(r3,r2,r1,r0,x3,x2,x1,x0,y3,y2,y1,y0) \ |
| 531 | do { \ |
| 532 | int _c1, _c2, _c3; \ |
| 533 | r0 = x0 + y0; \ |
| 534 | _c1 = r0 < x0; \ |
| 535 | r1 = x1 + y1; \ |
| 536 | _c2 = r1 < x1; \ |
| 537 | r1 += _c1; \ |
| 538 | _c2 |= r1 < _c1; \ |
| 539 | r2 = x2 + y2; \ |
| 540 | _c3 = r2 < x2; \ |
| 541 | r2 += _c2; \ |
| 542 | _c3 |= r2 < _c2; \ |
| 543 | r3 = x3 + y3 + _c3; \ |
| 544 | } while (0) |
| 545 | #endif |
| 546 | |
| 547 | #ifndef __FP_FRAC_SUB_3 |
| 548 | #define __FP_FRAC_SUB_3(r2,r1,r0,x2,x1,x0,y2,y1,y0) \ |
| 549 | do { \ |
| 550 | int _c1, _c2; \ |
| 551 | r0 = x0 - y0; \ |
| 552 | _c1 = r0 > x0; \ |
| 553 | r1 = x1 - y1; \ |
| 554 | _c2 = r1 > x1; \ |
| 555 | r1 -= _c1; \ |
| 556 | _c2 |= r1 > _c1; \ |
| 557 | r2 = x2 - y2 - _c2; \ |
| 558 | } while (0) |
| 559 | #endif |
| 560 | |
| 561 | #ifndef __FP_FRAC_SUB_4 |
| 562 | #define __FP_FRAC_SUB_4(r3,r2,r1,r0,x3,x2,x1,x0,y3,y2,y1,y0) \ |
| 563 | do { \ |
| 564 | int _c1, _c2, _c3; \ |
| 565 | r0 = x0 - y0; \ |
| 566 | _c1 = r0 > x0; \ |
| 567 | r1 = x1 - y1; \ |
| 568 | _c2 = r1 > x1; \ |
| 569 | r1 -= _c1; \ |
| 570 | _c2 |= r1 > _c1; \ |
| 571 | r2 = x2 - y2; \ |
| 572 | _c3 = r2 > x2; \ |
| 573 | r2 -= _c2; \ |
| 574 | _c3 |= r2 > _c2; \ |
| 575 | r3 = x3 - y3 - _c3; \ |
| 576 | } while (0) |
| 577 | #endif |
| 578 | |
| 579 | #ifndef __FP_FRAC_DEC_3 |
| 580 | #define __FP_FRAC_DEC_3(x2,x1,x0,y2,y1,y0) \ |
| 581 | do { \ |
| 582 | UWtype _t0, _t1, _t2; \ |
| 583 | _t0 = x0, _t1 = x1, _t2 = x2; \ |
| 584 | __FP_FRAC_SUB_3 (x2, x1, x0, _t2, _t1, _t0, y2, y1, y0); \ |
| 585 | } while (0) |
| 586 | #endif |
| 587 | |
| 588 | #ifndef __FP_FRAC_DEC_4 |
| 589 | #define __FP_FRAC_DEC_4(x3,x2,x1,x0,y3,y2,y1,y0) \ |
| 590 | do { \ |
| 591 | UWtype _t0, _t1, _t2, _t3; \ |
| 592 | _t0 = x0, _t1 = x1, _t2 = x2, _t3 = x3; \ |
| 593 | __FP_FRAC_SUB_4 (x3,x2,x1,x0,_t3,_t2,_t1,_t0, y3,y2,y1,y0); \ |
| 594 | } while (0) |
| 595 | #endif |
| 596 | |
| 597 | #ifndef __FP_FRAC_ADDI_4 |
| 598 | #define __FP_FRAC_ADDI_4(x3,x2,x1,x0,i) \ |
| 599 | do { \ |
| 600 | UWtype _t; \ |
| 601 | _t = ((x0 += i) < i); \ |
| 602 | x1 += _t; _t = (x1 < _t); \ |
| 603 | x2 += _t; _t = (x2 < _t); \ |
| 604 | x3 += _t; \ |
| 605 | } while (0) |
| 606 | #endif |
| 607 | |
| 608 | /* Convert FP values between word sizes. This appears to be more |
| 609 | * complicated than I'd have expected it to be, so these might be |
| 610 | * wrong... These macros are in any case somewhat bogus because they |
| 611 | * use information about what various FRAC_n variables look like |
| 612 | * internally [eg, that 2 word vars are X_f0 and x_f1]. But so do |
| 613 | * the ones in op-2.h and op-1.h. |
| 614 | */ |
| 615 | #define _FP_FRAC_CONV_1_4(dfs, sfs, D, S) \ |
| 616 | do { \ |
| 617 | if (S##_c != FP_CLS_NAN) \ |
| 618 | _FP_FRAC_SRS_4(S, (_FP_WFRACBITS_##sfs - _FP_WFRACBITS_##dfs), \ |
| 619 | _FP_WFRACBITS_##sfs); \ |
| 620 | else \ |
| 621 | _FP_FRAC_SRL_4(S, (_FP_WFRACBITS_##sfs - _FP_WFRACBITS_##dfs)); \ |
| 622 | D##_f = S##_f[0]; \ |
| 623 | } while (0) |
| 624 | |
| 625 | #define _FP_FRAC_CONV_2_4(dfs, sfs, D, S) \ |
| 626 | do { \ |
| 627 | if (S##_c != FP_CLS_NAN) \ |
| 628 | _FP_FRAC_SRS_4(S, (_FP_WFRACBITS_##sfs - _FP_WFRACBITS_##dfs), \ |
| 629 | _FP_WFRACBITS_##sfs); \ |
| 630 | else \ |
| 631 | _FP_FRAC_SRL_4(S, (_FP_WFRACBITS_##sfs - _FP_WFRACBITS_##dfs)); \ |
| 632 | D##_f0 = S##_f[0]; \ |
| 633 | D##_f1 = S##_f[1]; \ |
| 634 | } while (0) |
| 635 | |
| 636 | /* Assembly/disassembly for converting to/from integral types. |
| 637 | * No shifting or overflow handled here. |
| 638 | */ |
| 639 | /* Put the FP value X into r, which is an integer of size rsize. */ |
| 640 | #define _FP_FRAC_ASSEMBLE_4(r, X, rsize) \ |
| 641 | do { \ |
| 642 | if (rsize <= _FP_W_TYPE_SIZE) \ |
| 643 | r = X##_f[0]; \ |
| 644 | else if (rsize <= 2*_FP_W_TYPE_SIZE) \ |
| 645 | { \ |
| 646 | r = X##_f[1]; \ |
| 647 | r <<= _FP_W_TYPE_SIZE; \ |
| 648 | r += X##_f[0]; \ |
| 649 | } \ |
| 650 | else \ |
| 651 | { \ |
| 652 | /* I'm feeling lazy so we deal with int == 3words (implausible)*/ \ |
| 653 | /* and int == 4words as a single case. */ \ |
| 654 | r = X##_f[3]; \ |
| 655 | r <<= _FP_W_TYPE_SIZE; \ |
| 656 | r += X##_f[2]; \ |
| 657 | r <<= _FP_W_TYPE_SIZE; \ |
| 658 | r += X##_f[1]; \ |
| 659 | r <<= _FP_W_TYPE_SIZE; \ |
| 660 | r += X##_f[0]; \ |
| 661 | } \ |
| 662 | } while (0) |
| 663 | |
| 664 | /* "No disassemble Number Five!" */ |
| 665 | /* move an integer of size rsize into X's fractional part. We rely on |
| 666 | * the _f[] array consisting of words of size _FP_W_TYPE_SIZE to avoid |
| 667 | * having to mask the values we store into it. |
| 668 | */ |
| 669 | #define _FP_FRAC_DISASSEMBLE_4(X, r, rsize) \ |
| 670 | do { \ |
| 671 | X##_f[0] = r; \ |
| 672 | X##_f[1] = (rsize <= _FP_W_TYPE_SIZE ? 0 : r >> _FP_W_TYPE_SIZE); \ |
| 673 | X##_f[2] = (rsize <= 2*_FP_W_TYPE_SIZE ? 0 : r >> 2*_FP_W_TYPE_SIZE); \ |
| 674 | X##_f[3] = (rsize <= 3*_FP_W_TYPE_SIZE ? 0 : r >> 3*_FP_W_TYPE_SIZE); \ |
| 675 | } while (0) |
| 676 | |
| 677 | #define _FP_FRAC_CONV_4_1(dfs, sfs, D, S) \ |
| 678 | do { \ |
| 679 | D##_f[0] = S##_f; \ |
| 680 | D##_f[1] = D##_f[2] = D##_f[3] = 0; \ |
| 681 | _FP_FRAC_SLL_4(D, (_FP_WFRACBITS_##dfs - _FP_WFRACBITS_##sfs)); \ |
| 682 | } while (0) |
| 683 | |
| 684 | #define _FP_FRAC_CONV_4_2(dfs, sfs, D, S) \ |
| 685 | do { \ |
| 686 | D##_f[0] = S##_f0; \ |
| 687 | D##_f[1] = S##_f1; \ |
| 688 | D##_f[2] = D##_f[3] = 0; \ |
| 689 | _FP_FRAC_SLL_4(D, (_FP_WFRACBITS_##dfs - _FP_WFRACBITS_##sfs)); \ |
| 690 | } while (0) |
| 691 | |
| 692 | #endif |