arch/ppc/math-emu/op-common.h

   1 #define _FP_DECL(wc, X)                 \
   2   _FP_I_TYPE X##_c, X##_s, X##_e;       \
   3   _FP_FRAC_DECL_##wc(X)
   4
   5 /*
   6  * Finish truely unpacking a native fp value by classifying the kind
   7  * of fp value and normalizing both the exponent and the fraction.
   8  */
   9
  10 #define _FP_UNPACK_CANONICAL(fs, wc, X)                                 \
  11 do {                                                                    \
  12   switch (X##_e)                                                        \
  13   {                                                                     \
  14   default:                                                              \
  15     _FP_FRAC_HIGH_##wc(X) |= _FP_IMPLBIT_##fs;                          \
  16     _FP_FRAC_SLL_##wc(X, _FP_WORKBITS);                                 \
  17     X##_e -= _FP_EXPBIAS_##fs;                                          \
  18     X##_c = FP_CLS_NORMAL;                                              \
  19     break;                                                              \
  20                                                                         \
  21   case 0:                                                               \
  22     if (_FP_FRAC_ZEROP_##wc(X))                                         \
  23       X##_c = FP_CLS_ZERO;                                              \
  24     else                                                                \
  25       {                                                                 \
  26         /* a denormalized number */                                     \
  27         _FP_I_TYPE _shift;                                              \
  28         _FP_FRAC_CLZ_##wc(_shift, X);                                   \
  29         _shift -= _FP_FRACXBITS_##fs;                                   \
  30         _FP_FRAC_SLL_##wc(X, (_shift+_FP_WORKBITS));                    \
  31         X##_e -= _FP_EXPBIAS_##fs - 1 + _shift;                         \
  32         X##_c = FP_CLS_NORMAL;                                          \
  33       }                                                                 \
  34     break;                                                              \
  35                                                                         \
  36   case _FP_EXPMAX_##fs:                                                 \
  37     if (_FP_FRAC_ZEROP_##wc(X))                                         \
  38       X##_c = FP_CLS_INF;                                               \
  39     else                                                                \
  40       /* we don't differentiate between signaling and quiet nans */     \
  41       X##_c = FP_CLS_NAN;                                               \
  42     break;                                                              \
  43   }                                                                     \
  44 } while (0)
  45
  46
  47 /*
  48  * Before packing the bits back into the native fp result, take care
  49  * of such mundane things as rounding and overflow.  Also, for some
  50  * kinds of fp values, the original parts may not have been fully
  51  * extracted -- but that is ok, we can regenerate them now.
  52  */
  53
  54 #define _FP_PACK_CANONICAL(fs, wc, X)                           \
  55 ({int __ret = 0;                                                \
  56   switch (X##_c)                                                \
  57   {                                                             \
  58   case FP_CLS_NORMAL:                                           \
  59     X##_e += _FP_EXPBIAS_##fs;                                  \
  60     if (X##_e > 0)                                              \
  61       {                                                         \
  62         __ret |= _FP_ROUND(wc, X);                              \
  63         if (_FP_FRAC_OVERP_##wc(fs, X))                         \
  64           {                                                     \
  65             _FP_FRAC_SRL_##wc(X, (_FP_WORKBITS+1));             \
  66             X##_e++;                                            \
  67           }                                                     \
  68         else                                                    \
  69           _FP_FRAC_SRL_##wc(X, _FP_WORKBITS);                   \
  70         if (X##_e >= _FP_EXPMAX_##fs)                           \
  71           {                                                     \
  72             /* overflow to infinity */                          \
  73             X##_e = _FP_EXPMAX_##fs;                            \
  74             _FP_FRAC_SET_##wc(X, _FP_ZEROFRAC_##wc);            \
  75             __ret |= EFLAG_OVERFLOW;                            \
  76           }                                                     \
  77       }                                                         \
  78     else                                                        \
  79       {                                                         \
  80         /* we've got a denormalized number */                   \
  81         X##_e = -X##_e + 1;                                     \
  82         if (X##_e <= _FP_WFRACBITS_##fs)                        \
  83           {                                                     \
  84             _FP_FRAC_SRS_##wc(X, X##_e, _FP_WFRACBITS_##fs);    \
  85             _FP_FRAC_SLL_##wc(X, 1);                            \
  86             if (_FP_FRAC_OVERP_##wc(fs, X))                     \
  87               {                                                 \
  88                 X##_e = 1;                                      \
  89                 _FP_FRAC_SET_##wc(X, _FP_ZEROFRAC_##wc);        \
  90               }                                                 \
  91             else                                                \
  92               {                                                 \
  93                 X##_e = 0;                                      \
  94                 _FP_FRAC_SRL_##wc(X, _FP_WORKBITS+1);           \
  95                 __ret |= EFLAG_UNDERFLOW;                       \
  96               }                                                 \
  97           }                                                     \
  98         else                                                    \
  99           {                                                     \
 100             /* underflow to zero */                             \
 101             X##_e = 0;                                          \
 102             _FP_FRAC_SET_##wc(X, _FP_ZEROFRAC_##wc);            \
 103             __ret |= EFLAG_UNDERFLOW;                           \
 104           }                                                     \
 105       }                                                         \
 106     break;                                                      \
 107                                                                 \
 108   case FP_CLS_ZERO:                                             \
 109     X##_e = 0;                                                  \
 110     _FP_FRAC_SET_##wc(X, _FP_ZEROFRAC_##wc);                    \
 111     break;                                                      \
 112                                                                 \
 113   case FP_CLS_INF:                                              \
 114     X##_e = _FP_EXPMAX_##fs;                                    \
 115     _FP_FRAC_SET_##wc(X, _FP_ZEROFRAC_##wc);                    \
 116     break;                                                      \
 117                                                                 \
 118   case FP_CLS_NAN:                                              \
 119     X##_e = _FP_EXPMAX_##fs;                                    \
 120     if (!_FP_KEEPNANFRACP)                                      \
 121       {                                                         \
 122         _FP_FRAC_SET_##wc(X, _FP_NANFRAC_##fs);                 \
 123         X##_s = 0;                                              \
 124       }                                                         \
 125     else                                                        \
 126       _FP_FRAC_HIGH_##wc(X) |= _FP_QNANBIT_##fs;                \
 127     break;                                                      \
 128   }                                                             \
 129   __ret;                                                        \
 130 })
 131
 132
 133 /*
 134  * Main addition routine.  The input values should be cooked.
 135  */
 136
 137 #define _FP_ADD(fs, wc, R, X, Y)                                             \
 138 do {                                                                         \
 139   switch (_FP_CLS_COMBINE(X##_c, Y##_c))                                     \
 140   {                                                                          \
 141   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_NORMAL):                         \
 142     {                                                                        \
 143       /* shift the smaller number so that its exponent matches the larger */ \
 144       _FP_I_TYPE diff = X##_e - Y##_e;                                       \
 145                                                                              \
 146       if (diff < 0)                                                          \
 147         {                                                                    \
 148           diff = -diff;                                                      \
 149           if (diff <= _FP_WFRACBITS_##fs)                                    \
 150             _FP_FRAC_SRS_##wc(X, diff, _FP_WFRACBITS_##fs);                  \
 151           else if (!_FP_FRAC_ZEROP_##wc(X))                                  \
 152             _FP_FRAC_SET_##wc(X, _FP_MINFRAC_##wc);                          \
 153           else                                                               \
 154             _FP_FRAC_SET_##wc(X, _FP_ZEROFRAC_##wc);                         \
 155           R##_e = Y##_e;                                                     \
 156         }                                                                    \
 157       else                                                                   \
 158         {                                                                    \
 159           if (diff > 0)                                                      \
 160             {                                                                \
 161               if (diff <= _FP_WFRACBITS_##fs)                                \
 162                 _FP_FRAC_SRS_##wc(Y, diff, _FP_WFRACBITS_##fs);              \
 163               else if (!_FP_FRAC_ZEROP_##wc(Y))                              \
 164                 _FP_FRAC_SET_##wc(Y, _FP_MINFRAC_##wc);                      \
 165               else                                                           \
 166                 _FP_FRAC_SET_##wc(Y, _FP_ZEROFRAC_##wc);                     \
 167             }                                                                \
 168           R##_e = X##_e;                                                     \
 169         }                                                                    \
 170                                                                              \
 171       R##_c = FP_CLS_NORMAL;                                                 \
 172                                                                              \
 173       if (X##_s == Y##_s)                                                    \
 174         {                                                                    \
 175           R##_s = X##_s;                                                     \
 176           _FP_FRAC_ADD_##wc(R, X, Y);                                        \
 177           if (_FP_FRAC_OVERP_##wc(fs, R))                                    \
 178             {                                                                \
 179               _FP_FRAC_SRS_##wc(R, 1, _FP_WFRACBITS_##fs);                   \
 180               R##_e++;                                                       \
 181             }                                                                \
 182         }                                                                    \
 183       else                                                                   \
 184         {                                                                    \
 185           R##_s = X##_s;                                                     \
 186           _FP_FRAC_SUB_##wc(R, X, Y);                                        \
 187           if (_FP_FRAC_ZEROP_##wc(R))                                        \
 188             {                                                                \
 189               /* return an exact zero */                                     \
 190               if (FP_ROUNDMODE == FP_RND_MINF)                               \
 191                 R##_s |= Y##_s;                                              \
 192               else                                                           \
 193                 R##_s &= Y##_s;                                              \
 194               R##_c = FP_CLS_ZERO;                                           \
 195             }                                                                \
 196           else                                                               \
 197             {                                                                \
 198               if (_FP_FRAC_NEGP_##wc(R))                                     \
 199                 {                                                            \
 200                   _FP_FRAC_SUB_##wc(R, Y, X);                                \
 201                   R##_s = Y##_s;                                             \
 202                 }                                                            \
 203                                                                              \
 204               /* renormalize after subtraction */                            \
 205               _FP_FRAC_CLZ_##wc(diff, R);                                    \
 206               diff -= _FP_WFRACXBITS_##fs;                                   \
 207               if (diff)                                                      \
 208                 {                                                            \
 209                   R##_e -= diff;                                             \
 210                   _FP_FRAC_SLL_##wc(R, diff);                                \
 211                 }                                                            \
 212             }                                                                \
 213         }                                                                    \
 214       break;                                                                 \
 215     }                                                                        \
 216                                                                              \
 217   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_NAN):                               \
 218     _FP_CHOOSENAN(fs, wc, R, X, Y);                                          \
 219     break;                                                                   \
 220                                                                              \
 221   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_ZERO):                           \
 222     R##_e = X##_e;                                                           \
 223   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_NORMAL):                            \
 224   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_INF):                               \
 225   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_ZERO):                              \
 226     _FP_FRAC_COPY_##wc(R, X);                                                \
 227     R##_s = X##_s;                                                           \
 228     R##_c = X##_c;                                                           \
 229     break;                                                                   \
 230                                                                              \
 231   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_NORMAL):                           \
 232     R##_e = Y##_e;                                                           \
 233   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_NAN):                            \
 234   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_NAN):                               \
 235   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_NAN):                              \
 236     _FP_FRAC_COPY_##wc(R, Y);                                                \
 237     R##_s = Y##_s;                                                           \
 238     R##_c = Y##_c;                                                           \
 239     break;                                                                   \
 240                                                                              \
 241   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_INF):                               \
 242     if (X##_s != Y##_s)                                                      \
 243       {                                                                      \
 244         /* +INF + -INF => NAN */                                             \
 245         _FP_FRAC_SET_##wc(R, _FP_NANFRAC_##fs);                              \
 246         R##_s = X##_s ^ Y##_s;                                               \
 247         R##_c = FP_CLS_NAN;                                                  \
 248         break;                                                               \
 249       }                                                                      \
 250     /* FALLTHRU */                                                           \
 251                                                                              \
 252   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_NORMAL):                            \
 253   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_ZERO):                              \
 254     R##_s = X##_s;                                                           \
 255     R##_c = FP_CLS_INF;                                                      \
 256     break;                                                                   \
 257                                                                              \
 258   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_INF):                            \
 259   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_INF):                              \
 260     R##_s = Y##_s;                                                           \
 261     R##_c = FP_CLS_INF;                                                      \
 262     break;                                                                   \
 263                                                                              \
 264   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_ZERO):                             \
 265     /* make sure the sign is correct */                                      \
 266     if (FP_ROUNDMODE == FP_RND_MINF)                                         \
 267       R##_s = X##_s | Y##_s;                                                 \
 268     else                                                                     \
 269       R##_s = X##_s & Y##_s;                                                 \
 270     R##_c = FP_CLS_ZERO;                                                     \
 271     break;                                                                   \
 272                                                                              \
 273   default:                                                                   \
 274     abort();                                                                 \
 275   }                                                                          \
 276 } while (0)
 277
 278
 279 /*
 280  * Main negation routine.  FIXME -- when we care about setting exception
 281  * bits reliably, this will not do.  We should examine all of the fp classes.
 282  */
 283
 284 #define _FP_NEG(fs, wc, R, X)           \
 285   do {                                  \
 286     _FP_FRAC_COPY_##wc(R, X);           \
 287     R##_c = X##_c;                      \
 288     R##_e = X##_e;                      \
 289     R##_s = 1 ^ X##_s;                  \
 290   } while (0)
 291
 292
 293 /*
 294  * Main multiplication routine.  The input values should be cooked.
 295  */
 296
 297 #define _FP_MUL(fs, wc, R, X, Y)                        \
 298 do {                                                    \
 299   R##_s = X##_s ^ Y##_s;                                \
 300   switch (_FP_CLS_COMBINE(X##_c, Y##_c))                \
 301   {                                                     \
 302   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_NORMAL):    \
 303     R##_c = FP_CLS_NORMAL;                              \
 304     R##_e = X##_e + Y##_e + 1;                          \
 305                                                         \
 306     _FP_MUL_MEAT_##fs(R,X,Y);                           \
 307                                                         \
 308     if (_FP_FRAC_OVERP_##wc(fs, R))                     \
 309       _FP_FRAC_SRS_##wc(R, 1, _FP_WFRACBITS_##fs);      \
 310     else                                                \
 311       R##_e--;                                          \
 312     break;                                              \
 313                                                         \
 314   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_NAN):          \
 315     _FP_CHOOSENAN(fs, wc, R, X, Y);                     \
 316     break;                                              \
 317                                                         \
 318   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_NORMAL):       \
 319   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_INF):          \
 320   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_ZERO):         \
 321     R##_s = X##_s;                                      \
 322                                                         \
 323   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_INF):          \
 324   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_NORMAL):       \
 325   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_NORMAL):      \
 326   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_ZERO):        \
 327     _FP_FRAC_COPY_##wc(R, X);                           \
 328     R##_c = X##_c;                                      \
 329     break;                                              \
 330                                                         \
 331   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_NAN):       \
 332   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_NAN):          \
 333   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_NAN):         \
 334     R##_s = Y##_s;                                      \
 335                                                         \
 336   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_INF):       \
 337   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_ZERO):      \
 338     _FP_FRAC_COPY_##wc(R, Y);                           \
 339     R##_c = Y##_c;                                      \
 340     break;                                              \
 341                                                         \
 342   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_ZERO):         \
 343   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_INF):         \
 344     R##_c = FP_CLS_NAN;                                 \
 345     _FP_FRAC_SET_##wc(R, _FP_NANFRAC_##fs);             \
 346     break;                                              \
 347                                                         \
 348   default:                                              \
 349     abort();                                            \
 350   }                                                     \
 351 } while (0)
 352
 353
 354 /*
 355  * Main division routine.  The input values should be cooked.
 356  */
 357
 358 #define _FP_DIV(fs, wc, R, X, Y)                        \
 359 do {                                                    \
 360   R##_s = X##_s ^ Y##_s;                                \
 361   switch (_FP_CLS_COMBINE(X##_c, Y##_c))                \
 362   {                                                     \
 363   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_NORMAL):    \
 364     R##_c = FP_CLS_NORMAL;                              \
 365     R##_e = X##_e - Y##_e;                              \
 366                                                         \
 367     _FP_DIV_MEAT_##fs(R,X,Y);                           \
 368     break;                                              \
 369                                                         \
 370   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_NAN):          \
 371     _FP_CHOOSENAN(fs, wc, R, X, Y);                     \
 372     break;                                              \
 373                                                         \
 374   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_NORMAL):       \
 375   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_INF):          \
 376   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_ZERO):         \
 377     R##_s = X##_s;                                      \
 378     _FP_FRAC_COPY_##wc(R, X);                           \
 379     R##_c = X##_c;                                      \
 380     break;                                              \
 381                                                         \
 382   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_NAN):       \
 383   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_NAN):          \
 384   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_NAN):         \
 385     R##_s = Y##_s;                                      \
 386     _FP_FRAC_COPY_##wc(R, Y);                           \
 387     R##_c = Y##_c;                                      \
 388     break;                                              \
 389                                                         \
 390   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_INF):       \
 391   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_INF):         \
 392   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_NORMAL):      \
 393     R##_c = FP_CLS_ZERO;                                \
 394     break;                                              \
 395                                                         \
 396   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_ZERO):      \
 397   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_ZERO):         \
 398   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_NORMAL):       \
 399     R##_c = FP_CLS_INF;                                 \
 400     break;                                              \
 401                                                         \
 402   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_INF):          \
 403   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_ZERO):        \
 404     R##_c = FP_CLS_NAN;                                 \
 405     _FP_FRAC_SET_##wc(R, _FP_NANFRAC_##fs);             \
 406     break;                                              \
 407                                                         \
 408   default:                                              \
 409     abort();                                            \
 410   }                                                     \
 411 } while (0)
 412
 413
 414 /*
 415  * Main differential comparison routine.  The inputs should be raw not
 416  * cooked.  The return is -1,0,1 for normal values, 2 otherwise.
 417  */
 418
 419 #define _FP_CMP(fs, wc, ret, X, Y, un)                                  \
 420   do {                                                                  \
 421     /* NANs are unordered */                                            \
 422     if ((X##_e == _FP_EXPMAX_##fs && !_FP_FRAC_ZEROP_##wc(X))           \
 423         || (Y##_e == _FP_EXPMAX_##fs && !_FP_FRAC_ZEROP_##wc(Y)))       \
 424       {                                                                 \
 425         ret = un;                                                       \
 426       }                                                                 \
 427     else                                                                \
 428       {                                                                 \
 429         int __x_zero = (!X##_e && _FP_FRAC_ZEROP_##wc(X)) ? 1 : 0;      \
 430         int __y_zero = (!Y##_e && _FP_FRAC_ZEROP_##wc(Y)) ? 1 : 0;      \
 431                                                                         \
 432         if (__x_zero && __y_zero)                                       \
 433           ret = 0;                                                      \
 434         else if (__x_zero)                                              \
 435           ret = Y##_s ? 1 : -1;                                         \
 436         else if (__y_zero)                                              \
 437           ret = X##_s ? -1 : 1;                                         \
 438         else if (X##_s != Y##_s)                                        \
 439           ret = X##_s ? -1 : 1;                                         \
 440         else if (X##_e > Y##_e)                                         \
 441           ret = X##_s ? -1 : 1;                                         \
 442         else if (X##_e < Y##_e)                                         \
 443           ret = X##_s ? 1 : -1;                                         \
 444         else if (_FP_FRAC_GT_##wc(X, Y))                                \
 445           ret = X##_s ? -1 : 1;                                         \
 446         else if (_FP_FRAC_GT_##wc(Y, X))                                \
 447           ret = X##_s ? 1 : -1;                                         \
 448         else                                                            \
 449           ret = 0;                                                      \
 450       }                                                                 \
 451   } while (0)
 452
 453
 454 /* Simplification for strict equality.  */
 455
 456 #define _FP_CMP_EQ(fs, wc, ret, X, Y)                                     \
 457   do {                                                                    \
 458     /* NANs are unordered */                                              \
 459     if ((X##_e == _FP_EXPMAX_##fs && !_FP_FRAC_ZEROP_##wc(X))             \
 460         || (Y##_e == _FP_EXPMAX_##fs && !_FP_FRAC_ZEROP_##wc(Y)))         \
 461       {                                                                   \
 462         ret = 1;                                                          \
 463       }                                                                   \
 464     else                                                                  \
 465       {                                                                   \
 466         ret = !(X##_e == Y##_e                                            \
 467                 && _FP_FRAC_EQ_##wc(X, Y)                                 \
 468                 && (X##_s == Y##_s || !X##_e && _FP_FRAC_ZEROP_##wc(X))); \
 469       }                                                                   \
 470   } while (0)
 471
 472 /*
 473  * Main square root routine.  The input value should be cooked.
 474  */
 475
 476 #define _FP_SQRT(fs, wc, R, X)                                          \
 477 do {                                                                    \
 478     _FP_FRAC_DECL_##wc(T); _FP_FRAC_DECL_##wc(S);                       \
 479     _FP_W_TYPE q;                                                       \
 480     switch (X##_c)                                                      \
 481     {                                                                   \
 482     case FP_CLS_NAN:                                                    \
 483         R##_s = 0;                                                      \
 484         R##_c = FP_CLS_NAN;                                             \
 485         _FP_FRAC_SET_##wc(X, _FP_ZEROFRAC_##wc);                        \
 486         break;                                                          \
 487     case FP_CLS_INF:                                                    \
 488         if (X##_s)                                                      \
 489           {                                                             \
 490             R##_s = 0;                                                  \
 491             R##_c = FP_CLS_NAN; /* sNAN */                              \
 492           }                                                             \
 493         else                                                            \
 494           {                                                             \
 495             R##_s = 0;                                                  \
 496             R##_c = FP_CLS_INF; /* sqrt(+inf) = +inf */                 \
 497           }                                                             \
 498         break;                                                          \
 499     case FP_CLS_ZERO:                                                   \
 500         R##_s = X##_s;                                                  \
 501         R##_c = FP_CLS_ZERO; /* sqrt(+-0) = +-0 */                      \
 502         break;                                                          \
 503     case FP_CLS_NORMAL:                                                 \
 504         R##_s = 0;                                                      \
 505         if (X##_s)                                                      \
 506           {                                                             \
 507             R##_c = FP_CLS_NAN; /* sNAN */                              \
 508             break;                                                      \
 509           }                                                             \
 510         R##_c = FP_CLS_NORMAL;                                          \
 511         if (X##_e & 1)                                                  \
 512           _FP_FRAC_SLL_##wc(X, 1);                                      \
 513         R##_e = X##_e >> 1;                                             \
 514         _FP_FRAC_SET_##wc(S, _FP_ZEROFRAC_##wc);                        \
 515         _FP_FRAC_SET_##wc(R, _FP_ZEROFRAC_##wc);                        \
 516         q = _FP_OVERFLOW_##fs;                                          \
 517         _FP_FRAC_SLL_##wc(X, 1);                                        \
 518         _FP_SQRT_MEAT_##wc(R, S, T, X, q);                              \
 519         _FP_FRAC_SRL_##wc(R, 1);                                        \
 520     }                                                                   \
 521   } while (0)
 522
 523 /*
 524  * Convert from FP to integer
 525  */
 526
 527 /* "When a NaN, infinity, large positive argument >= 2147483648.0, or
 528  * large negative argument <= -2147483649.0 is converted to an integer,
 529  * the invalid_current bit...should be set and fp_exception_IEEE_754 should
 530  * be raised. If the floating point invalid trap is disabled, no trap occurs
 531  * and a numerical result is generated: if the sign bit of the operand
 532  * is 0, the result is 2147483647; if the sign bit of the operand is 1,
 533  * the result is -2147483648."
 534  * Similarly for conversion to extended ints, except that the boundaries
 535  * are >= 2^63, <= -(2^63 + 1), and the results are 2^63 + 1 for s=0 and
 536  * -2^63 for s=1.
 537  * -- SPARC Architecture Manual V9, Appendix B, which specifies how
 538  * SPARCs resolve implementation dependencies in the IEEE-754 spec.
 539  * I don't believe that the code below follows this. I'm not even sure
 540  * it's right!
 541  * It doesn't cope with needing to convert to an n bit integer when there
 542  * is no n bit integer type. Fortunately gcc provides long long so this
 543  * isn't a problem for sparc32.
 544  * I have, however, fixed its NaN handling to conform as above.
 545  *         -- PMM 02/1998
 546  * NB: rsigned is not 'is r declared signed?' but 'should the value stored
 547  * in r be signed or unsigned?'. r is always(?) declared unsigned.
 548  * Comments below are mine, BTW -- PMM
 549  */
 550 #define _FP_TO_INT(fs, wc, r, X, rsize, rsigned)                        \
 551   do {                                                                  \
 552     switch (X##_c)                                                      \
 553       {                                                                 \
 554       case FP_CLS_NORMAL:                                               \
 555         if (X##_e < 0)                                                  \
 556           {                                                             \
 557           /* case FP_CLS_NAN: see above! */                             \
 558           case FP_CLS_ZERO:                                             \
 559             r = 0;                                                      \
 560           }                                                             \
 561         else if (X##_e >= rsize - (rsigned != 0))                       \
 562           {     /* overflow */                                          \
 563           case FP_CLS_NAN:                                              \
 564           case FP_CLS_INF:                                              \
 565             if (rsigned)                                                \
 566               {                                                         \
 567                 r = 1;                                                  \
 568                 r <<= rsize - 1;                                        \
 569                 r -= 1 - X##_s;                                         \
 570               }                                                         \
 571             else                                                        \
 572               {                                                         \
 573                 r = 0;                                                  \
 574                 if (!X##_s)                                             \
 575                   r = ~r;                                               \
 576               }                                                         \
 577           }                                                             \
 578         else                                                            \
 579           {                                                             \
 580             if (_FP_W_TYPE_SIZE*wc < rsize)                             \
 581               {                                                         \
 582                 _FP_FRAC_ASSEMBLE_##wc(r, X, rsize);                    \
 583                 r <<= X##_e - _FP_WFRACBITS_##fs;                       \
 584               }                                                         \
 585             else                                                        \
 586               {                                                         \
 587                 if (X##_e >= _FP_WFRACBITS_##fs)                        \
 588                   _FP_FRAC_SLL_##wc(X, (X##_e - _FP_WFRACBITS_##fs + 1));\
 589                 else                                                    \
 590                   _FP_FRAC_SRL_##wc(X, (_FP_WFRACBITS_##fs - X##_e - 1));\
 591                 _FP_FRAC_ASSEMBLE_##wc(r, X, rsize);                    \
 592               }                                                         \
 593             if (rsigned && X##_s)                                       \
 594               r = -r;                                                   \
 595           }                                                             \
 596         break;                                                          \
 597       }                                                                 \
 598   } while (0)
 599
 600 #define _FP_FROM_INT(fs, wc, X, r, rsize, rtype)                        \
 601   do {                                                                  \
 602     if (r)                                                              \
 603       {                                                                 \
 604         X##_c = FP_CLS_NORMAL;                                          \
 605                                                                         \
 606         if ((X##_s = (r < 0)))                                          \
 607           r = -r;                                                       \
 608         /* Note that `r' is now considered unsigned, so we don't have   \
 609            to worry about the single signed overflow case.  */          \
 610                                                                         \
 611         if (rsize <= _FP_W_TYPE_SIZE)                                   \
 612           __FP_CLZ(X##_e, r);                                           \
 613         else                                                            \
 614           __FP_CLZ_2(X##_e, (_FP_W_TYPE)(r >> _FP_W_TYPE_SIZE),         \
 615                      (_FP_W_TYPE)r);                                    \
 616         if (rsize < _FP_W_TYPE_SIZE)                                    \
 617                 X##_e -= (_FP_W_TYPE_SIZE - rsize);                     \
 618         X##_e = rsize - X##_e - 1;                                      \
 619                                                                         \
 620         if (_FP_FRACBITS_##fs < rsize && _FP_WFRACBITS_##fs < X##_e)    \
 621           __FP_FRAC_SRS_1(r, (X##_e - _FP_WFRACBITS_##fs), rsize);      \
 622         r &= ~((_FP_W_TYPE)1 << X##_e);                                 \
 623         _FP_FRAC_DISASSEMBLE_##wc(X, ((unsigned rtype)r), rsize);       \
 624         _FP_FRAC_SLL_##wc(X, (_FP_WFRACBITS_##fs - X##_e - 1));         \
 625       }                                                                 \
 626     else                                                                \
 627       {                                                                 \
 628         X##_c = FP_CLS_ZERO, X##_s = 0;                                 \
 629       }                                                                 \
 630   } while (0)
 631
 632
 633 #define FP_CONV(dfs,sfs,dwc,swc,D,S)                    \
 634   do {                                                  \
 635     _FP_FRAC_CONV_##dwc##_##swc(dfs, sfs, D, S);        \
 636     D##_e = S##_e;                                      \
 637     D##_c = S##_c;                                      \
 638     D##_s = S##_s;                                      \
 639   } while (0)
 640
 641 /*
 642  * Helper primitives.
 643  */
 644
 645 /* Count leading zeros in a word.  */
 646
 647 #ifndef __FP_CLZ
 648 #if _FP_W_TYPE_SIZE < 64
 649 /* this is just to shut the compiler up about shifts > word length -- PMM 02/1998 */
 650 #define __FP_CLZ(r, x)                          \
 651   do {                                          \
 652     _FP_W_TYPE _t = (x);                        \
 653     r = _FP_W_TYPE_SIZE - 1;                    \
 654     if (_t > 0xffff) r -= 16;                   \
 655     if (_t > 0xffff) _t >>= 16;                 \
 656     if (_t > 0xff) r -= 8;                      \
 657     if (_t > 0xff) _t >>= 8;                    \
 658     if (_t & 0xf0) r -= 4;                      \
 659     if (_t & 0xf0) _t >>= 4;                    \
 660     if (_t & 0xc) r -= 2;                       \
 661     if (_t & 0xc) _t >>= 2;                     \
 662     if (_t & 0x2) r -= 1;                       \
 663   } while (0)
 664 #else /* not _FP_W_TYPE_SIZE < 64 */
 665 #define __FP_CLZ(r, x)                          \
 666   do {                                          \
 667     _FP_W_TYPE _t = (x);                        \
 668     r = _FP_W_TYPE_SIZE - 1;                    \
 669     if (_t > 0xffffffff) r -= 32;               \
 670     if (_t > 0xffffffff) _t >>= 32;             \
 671     if (_t > 0xffff) r -= 16;                   \
 672     if (_t > 0xffff) _t >>= 16;                 \
 673     if (_t > 0xff) r -= 8;                      \
 674     if (_t > 0xff) _t >>= 8;                    \
 675     if (_t & 0xf0) r -= 4;                      \
 676     if (_t & 0xf0) _t >>= 4;                    \
 677     if (_t & 0xc) r -= 2;                       \
 678     if (_t & 0xc) _t >>= 2;                     \
 679     if (_t & 0x2) r -= 1;                       \
 680   } while (0)
 681 #endif /* not _FP_W_TYPE_SIZE < 64 */
 682 #endif /* ndef __FP_CLZ */
 683
 684 #define _FP_DIV_HELP_imm(q, r, n, d)            \
 685   do {                                          \
 686     q = n / d, r = n % d;                       \
 687   } while (0)
 688