math-emu: correct test for downshifting fraction in _FP_FROM_INT()
[linux-2.6.git] / include / math-emu / op-common.h
1 /* Software floating-point emulation. Common operations.
2    Copyright (C) 1997,1998,1999 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4    Contributed by Richard Henderson (rth@cygnus.com),
5                   Jakub Jelinek (jj@ultra.linux.cz),
6                   David S. Miller (davem@redhat.com) 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 Library General Public License as
11    published by the Free Software Foundation; either version 2 of the
12    License, or (at your option) any later version.
13
14    The GNU C Library is distributed in the hope that it will be useful,
15    but WITHOUT ANY WARRANTY; without even the implied warranty of
16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17    Library General Public License for more details.
18
19    You should have received a copy of the GNU Library General Public
20    License along with the GNU C Library; see the file COPYING.LIB.  If
21    not, write to the Free Software Foundation, Inc.,
22    59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
23
24 #ifndef __MATH_EMU_OP_COMMON_H__
25 #define __MATH_EMU_OP_COMMON_H__
26
27 #define _FP_DECL(wc, X)                 \
28   _FP_I_TYPE X##_c=0, X##_s=0, X##_e=0; \
29   _FP_FRAC_DECL_##wc(X)
30
31 /*
32  * Finish truly unpacking a native fp value by classifying the kind
33  * of fp value and normalizing both the exponent and the fraction.
34  */
35
36 #define _FP_UNPACK_CANONICAL(fs, wc, X)                                 \
37 do {                                                                    \
38   switch (X##_e)                                                        \
39   {                                                                     \
40   default:                                                              \
41     _FP_FRAC_HIGH_RAW_##fs(X) |= _FP_IMPLBIT_##fs;                      \
42     _FP_FRAC_SLL_##wc(X, _FP_WORKBITS);                                 \
43     X##_e -= _FP_EXPBIAS_##fs;                                          \
44     X##_c = FP_CLS_NORMAL;                                              \
45     break;                                                              \
46                                                                         \
47   case 0:                                                               \
48     if (_FP_FRAC_ZEROP_##wc(X))                                         \
49       X##_c = FP_CLS_ZERO;                                              \
50     else                                                                \
51       {                                                                 \
52         /* a denormalized number */                                     \
53         _FP_I_TYPE _shift;                                              \
54         _FP_FRAC_CLZ_##wc(_shift, X);                                   \
55         _shift -= _FP_FRACXBITS_##fs;                                   \
56         _FP_FRAC_SLL_##wc(X, (_shift+_FP_WORKBITS));                    \
57         X##_e -= _FP_EXPBIAS_##fs - 1 + _shift;                         \
58         X##_c = FP_CLS_NORMAL;                                          \
59         FP_SET_EXCEPTION(FP_EX_DENORM);                                 \
60         if (FP_DENORM_ZERO)                                             \
61           {                                                             \
62             FP_SET_EXCEPTION(FP_EX_INEXACT);                            \
63             X##_c = FP_CLS_ZERO;                                        \
64           }                                                             \
65       }                                                                 \
66     break;                                                              \
67                                                                         \
68   case _FP_EXPMAX_##fs:                                                 \
69     if (_FP_FRAC_ZEROP_##wc(X))                                         \
70       X##_c = FP_CLS_INF;                                               \
71     else                                                                \
72       {                                                                 \
73         X##_c = FP_CLS_NAN;                                             \
74         /* Check for signaling NaN */                                   \
75         if (!(_FP_FRAC_HIGH_RAW_##fs(X) & _FP_QNANBIT_##fs))            \
76           FP_SET_EXCEPTION(FP_EX_INVALID | FP_EX_INVALID_SNAN);         \
77       }                                                                 \
78     break;                                                              \
79   }                                                                     \
80 } while (0)
81
82 /*
83  * Before packing the bits back into the native fp result, take care
84  * of such mundane things as rounding and overflow.  Also, for some
85  * kinds of fp values, the original parts may not have been fully
86  * extracted -- but that is ok, we can regenerate them now.
87  */
88
89 #define _FP_PACK_CANONICAL(fs, wc, X)                           \
90 do {                                                            \
91   switch (X##_c)                                                \
92   {                                                             \
93   case FP_CLS_NORMAL:                                           \
94     X##_e += _FP_EXPBIAS_##fs;                                  \
95     if (X##_e > 0)                                              \
96       {                                                         \
97         _FP_ROUND(wc, X);                                       \
98         if (_FP_FRAC_OVERP_##wc(fs, X))                         \
99           {                                                     \
100             _FP_FRAC_CLEAR_OVERP_##wc(fs, X);                   \
101             X##_e++;                                            \
102           }                                                     \
103         _FP_FRAC_SRL_##wc(X, _FP_WORKBITS);                     \
104         if (X##_e >= _FP_EXPMAX_##fs)                           \
105           {                                                     \
106             /* overflow */                                      \
107             switch (FP_ROUNDMODE)                               \
108               {                                                 \
109               case FP_RND_NEAREST:                              \
110                 X##_c = FP_CLS_INF;                             \
111                 break;                                          \
112               case FP_RND_PINF:                                 \
113                 if (!X##_s) X##_c = FP_CLS_INF;                 \
114                 break;                                          \
115               case FP_RND_MINF:                                 \
116                 if (X##_s) X##_c = FP_CLS_INF;                  \
117                 break;                                          \
118               }                                                 \
119             if (X##_c == FP_CLS_INF)                            \
120               {                                                 \
121                 /* Overflow to infinity */                      \
122                 X##_e = _FP_EXPMAX_##fs;                        \
123                 _FP_FRAC_SET_##wc(X, _FP_ZEROFRAC_##wc);        \
124               }                                                 \
125             else                                                \
126               {                                                 \
127                 /* Overflow to maximum normal */                \
128                 X##_e = _FP_EXPMAX_##fs - 1;                    \
129                 _FP_FRAC_SET_##wc(X, _FP_MAXFRAC_##wc);         \
130               }                                                 \
131             FP_SET_EXCEPTION(FP_EX_OVERFLOW);                   \
132             FP_SET_EXCEPTION(FP_EX_INEXACT);                    \
133           }                                                     \
134       }                                                         \
135     else                                                        \
136       {                                                         \
137         /* we've got a denormalized number */                   \
138         X##_e = -X##_e + 1;                                     \
139         if (X##_e <= _FP_WFRACBITS_##fs)                        \
140           {                                                     \
141             _FP_FRAC_SRS_##wc(X, X##_e, _FP_WFRACBITS_##fs);    \
142             if (_FP_FRAC_HIGH_##fs(X)                           \
143                 & (_FP_OVERFLOW_##fs >> 1))                     \
144               {                                                 \
145                 X##_e = 1;                                      \
146                 _FP_FRAC_SET_##wc(X, _FP_ZEROFRAC_##wc);        \
147               }                                                 \
148             else                                                \
149               {                                                 \
150                 _FP_ROUND(wc, X);                               \
151                 if (_FP_FRAC_HIGH_##fs(X)                       \
152                    & (_FP_OVERFLOW_##fs >> 1))                  \
153                   {                                             \
154                     X##_e = 1;                                  \
155                     _FP_FRAC_SET_##wc(X, _FP_ZEROFRAC_##wc);    \
156                     FP_SET_EXCEPTION(FP_EX_INEXACT);            \
157                   }                                             \
158                 else                                            \
159                   {                                             \
160                     X##_e = 0;                                  \
161                     _FP_FRAC_SRL_##wc(X, _FP_WORKBITS);         \
162                   }                                             \
163               }                                                 \
164             if ((FP_CUR_EXCEPTIONS & FP_EX_INEXACT) ||          \
165                 (FP_TRAPPING_EXCEPTIONS & FP_EX_UNDERFLOW))     \
166                 FP_SET_EXCEPTION(FP_EX_UNDERFLOW);              \
167           }                                                     \
168         else                                                    \
169           {                                                     \
170             /* underflow to zero */                             \
171             X##_e = 0;                                          \
172             if (!_FP_FRAC_ZEROP_##wc(X))                        \
173               {                                                 \
174                 _FP_FRAC_SET_##wc(X, _FP_MINFRAC_##wc);         \
175                 _FP_ROUND(wc, X);                               \
176                 _FP_FRAC_LOW_##wc(X) >>= (_FP_WORKBITS);        \
177               }                                                 \
178             FP_SET_EXCEPTION(FP_EX_UNDERFLOW);                  \
179           }                                                     \
180       }                                                         \
181     break;                                                      \
182                                                                 \
183   case FP_CLS_ZERO:                                             \
184     X##_e = 0;                                                  \
185     _FP_FRAC_SET_##wc(X, _FP_ZEROFRAC_##wc);                    \
186     break;                                                      \
187                                                                 \
188   case FP_CLS_INF:                                              \
189     X##_e = _FP_EXPMAX_##fs;                                    \
190     _FP_FRAC_SET_##wc(X, _FP_ZEROFRAC_##wc);                    \
191     break;                                                      \
192                                                                 \
193   case FP_CLS_NAN:                                              \
194     X##_e = _FP_EXPMAX_##fs;                                    \
195     if (!_FP_KEEPNANFRACP)                                      \
196       {                                                         \
197         _FP_FRAC_SET_##wc(X, _FP_NANFRAC_##fs);                 \
198         X##_s = _FP_NANSIGN_##fs;                               \
199       }                                                         \
200     else                                                        \
201       _FP_FRAC_HIGH_RAW_##fs(X) |= _FP_QNANBIT_##fs;            \
202     break;                                                      \
203   }                                                             \
204 } while (0)
205
206 /* This one accepts raw argument and not cooked,  returns
207  * 1 if X is a signaling NaN.
208  */
209 #define _FP_ISSIGNAN(fs, wc, X)                                 \
210 ({                                                              \
211   int __ret = 0;                                                \
212   if (X##_e == _FP_EXPMAX_##fs)                                 \
213     {                                                           \
214       if (!_FP_FRAC_ZEROP_##wc(X)                               \
215           && !(_FP_FRAC_HIGH_RAW_##fs(X) & _FP_QNANBIT_##fs))   \
216         __ret = 1;                                              \
217     }                                                           \
218   __ret;                                                        \
219 })
220
221
222
223
224
225 /*
226  * Main addition routine.  The input values should be cooked.
227  */
228
229 #define _FP_ADD_INTERNAL(fs, wc, R, X, Y, OP)                                \
230 do {                                                                         \
231   switch (_FP_CLS_COMBINE(X##_c, Y##_c))                                     \
232   {                                                                          \
233   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_NORMAL):                         \
234     {                                                                        \
235       /* shift the smaller number so that its exponent matches the larger */ \
236       _FP_I_TYPE diff = X##_e - Y##_e;                                       \
237                                                                              \
238       if (diff < 0)                                                          \
239         {                                                                    \
240           diff = -diff;                                                      \
241           if (diff <= _FP_WFRACBITS_##fs)                                    \
242             _FP_FRAC_SRS_##wc(X, diff, _FP_WFRACBITS_##fs);                  \
243           else if (!_FP_FRAC_ZEROP_##wc(X))                                  \
244             _FP_FRAC_SET_##wc(X, _FP_MINFRAC_##wc);                          \
245           R##_e = Y##_e;                                                     \
246         }                                                                    \
247       else                                                                   \
248         {                                                                    \
249           if (diff > 0)                                                      \
250             {                                                                \
251               if (diff <= _FP_WFRACBITS_##fs)                                \
252                 _FP_FRAC_SRS_##wc(Y, diff, _FP_WFRACBITS_##fs);              \
253               else if (!_FP_FRAC_ZEROP_##wc(Y))                              \
254                 _FP_FRAC_SET_##wc(Y, _FP_MINFRAC_##wc);                      \
255             }                                                                \
256           R##_e = X##_e;                                                     \
257         }                                                                    \
258                                                                              \
259       R##_c = FP_CLS_NORMAL;                                                 \
260                                                                              \
261       if (X##_s == Y##_s)                                                    \
262         {                                                                    \
263           R##_s = X##_s;                                                     \
264           _FP_FRAC_ADD_##wc(R, X, Y);                                        \
265           if (_FP_FRAC_OVERP_##wc(fs, R))                                    \
266             {                                                                \
267               _FP_FRAC_SRS_##wc(R, 1, _FP_WFRACBITS_##fs);                   \
268               R##_e++;                                                       \
269             }                                                                \
270         }                                                                    \
271       else                                                                   \
272         {                                                                    \
273           R##_s = X##_s;                                                     \
274           _FP_FRAC_SUB_##wc(R, X, Y);                                        \
275           if (_FP_FRAC_ZEROP_##wc(R))                                        \
276             {                                                                \
277               /* return an exact zero */                                     \
278               if (FP_ROUNDMODE == FP_RND_MINF)                               \
279                 R##_s |= Y##_s;                                              \
280               else                                                           \
281                 R##_s &= Y##_s;                                              \
282               R##_c = FP_CLS_ZERO;                                           \
283             }                                                                \
284           else                                                               \
285             {                                                                \
286               if (_FP_FRAC_NEGP_##wc(R))                                     \
287                 {                                                            \
288                   _FP_FRAC_SUB_##wc(R, Y, X);                                \
289                   R##_s = Y##_s;                                             \
290                 }                                                            \
291                                                                              \
292               /* renormalize after subtraction */                            \
293               _FP_FRAC_CLZ_##wc(diff, R);                                    \
294               diff -= _FP_WFRACXBITS_##fs;                                   \
295               if (diff)                                                      \
296                 {                                                            \
297                   R##_e -= diff;                                             \
298                   _FP_FRAC_SLL_##wc(R, diff);                                \
299                 }                                                            \
300             }                                                                \
301         }                                                                    \
302       break;                                                                 \
303     }                                                                        \
304                                                                              \
305   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_NAN):                               \
306     _FP_CHOOSENAN(fs, wc, R, X, Y, OP);                                      \
307     break;                                                                   \
308                                                                              \
309   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_ZERO):                           \
310     R##_e = X##_e;                                                           \
311   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_NORMAL):                            \
312   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_INF):                               \
313   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_ZERO):                              \
314     _FP_FRAC_COPY_##wc(R, X);                                                \
315     R##_s = X##_s;                                                           \
316     R##_c = X##_c;                                                           \
317     break;                                                                   \
318                                                                              \
319   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_NORMAL):                           \
320     R##_e = Y##_e;                                                           \
321   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_NAN):                            \
322   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_NAN):                               \
323   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_NAN):                              \
324     _FP_FRAC_COPY_##wc(R, Y);                                                \
325     R##_s = Y##_s;                                                           \
326     R##_c = Y##_c;                                                           \
327     break;                                                                   \
328                                                                              \
329   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_INF):                               \
330     if (X##_s != Y##_s)                                                      \
331       {                                                                      \
332         /* +INF + -INF => NAN */                                             \
333         _FP_FRAC_SET_##wc(R, _FP_NANFRAC_##fs);                              \
334         R##_s = _FP_NANSIGN_##fs;                                            \
335         R##_c = FP_CLS_NAN;                                                  \
336         FP_SET_EXCEPTION(FP_EX_INVALID | FP_EX_INVALID_ISI);                 \
337         break;                                                               \
338       }                                                                      \
339     /* FALLTHRU */                                                           \
340                                                                              \
341   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_NORMAL):                            \
342   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_ZERO):                              \
343     R##_s = X##_s;                                                           \
344     R##_c = FP_CLS_INF;                                                      \
345     break;                                                                   \
346                                                                              \
347   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_INF):                            \
348   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_INF):                              \
349     R##_s = Y##_s;                                                           \
350     R##_c = FP_CLS_INF;                                                      \
351     break;                                                                   \
352                                                                              \
353   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_ZERO):                             \
354     /* make sure the sign is correct */                                      \
355     if (FP_ROUNDMODE == FP_RND_MINF)                                         \
356       R##_s = X##_s | Y##_s;                                                 \
357     else                                                                     \
358       R##_s = X##_s & Y##_s;                                                 \
359     R##_c = FP_CLS_ZERO;                                                     \
360     break;                                                                   \
361                                                                              \
362   default:                                                                   \
363     abort();                                                                 \
364   }                                                                          \
365 } while (0)
366
367 #define _FP_ADD(fs, wc, R, X, Y) _FP_ADD_INTERNAL(fs, wc, R, X, Y, '+')
368 #define _FP_SUB(fs, wc, R, X, Y)                                             \
369   do {                                                                       \
370     if (Y##_c != FP_CLS_NAN) Y##_s ^= 1;                                     \
371     _FP_ADD_INTERNAL(fs, wc, R, X, Y, '-');                                  \
372   } while (0)
373
374
375 /*
376  * Main negation routine.  FIXME -- when we care about setting exception
377  * bits reliably, this will not do.  We should examine all of the fp classes.
378  */
379
380 #define _FP_NEG(fs, wc, R, X)           \
381   do {                                  \
382     _FP_FRAC_COPY_##wc(R, X);           \
383     R##_c = X##_c;                      \
384     R##_e = X##_e;                      \
385     R##_s = 1 ^ X##_s;                  \
386   } while (0)
387
388
389 /*
390  * Main multiplication routine.  The input values should be cooked.
391  */
392
393 #define _FP_MUL(fs, wc, R, X, Y)                        \
394 do {                                                    \
395   R##_s = X##_s ^ Y##_s;                                \
396   switch (_FP_CLS_COMBINE(X##_c, Y##_c))                \
397   {                                                     \
398   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_NORMAL):    \
399     R##_c = FP_CLS_NORMAL;                              \
400     R##_e = X##_e + Y##_e + 1;                          \
401                                                         \
402     _FP_MUL_MEAT_##fs(R,X,Y);                           \
403                                                         \
404     if (_FP_FRAC_OVERP_##wc(fs, R))                     \
405       _FP_FRAC_SRS_##wc(R, 1, _FP_WFRACBITS_##fs);      \
406     else                                                \
407       R##_e--;                                          \
408     break;                                              \
409                                                         \
410   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_NAN):          \
411     _FP_CHOOSENAN(fs, wc, R, X, Y, '*');                \
412     break;                                              \
413                                                         \
414   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_NORMAL):       \
415   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_INF):          \
416   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_ZERO):         \
417     R##_s = X##_s;                                      \
418                                                         \
419   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_INF):          \
420   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_NORMAL):       \
421   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_NORMAL):      \
422   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_ZERO):        \
423     _FP_FRAC_COPY_##wc(R, X);                           \
424     R##_c = X##_c;                                      \
425     break;                                              \
426                                                         \
427   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_NAN):       \
428   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_NAN):          \
429   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_NAN):         \
430     R##_s = Y##_s;                                      \
431                                                         \
432   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_INF):       \
433   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_ZERO):      \
434     _FP_FRAC_COPY_##wc(R, Y);                           \
435     R##_c = Y##_c;                                      \
436     break;                                              \
437                                                         \
438   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_ZERO):         \
439   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_INF):         \
440     R##_s = _FP_NANSIGN_##fs;                           \
441     R##_c = FP_CLS_NAN;                                 \
442     _FP_FRAC_SET_##wc(R, _FP_NANFRAC_##fs);             \
443     FP_SET_EXCEPTION(FP_EX_INVALID | FP_EX_INVALID_IMZ);\
444     break;                                              \
445                                                         \
446   default:                                              \
447     abort();                                            \
448   }                                                     \
449 } while (0)
450
451
452 /*
453  * Main division routine.  The input values should be cooked.
454  */
455
456 #define _FP_DIV(fs, wc, R, X, Y)                        \
457 do {                                                    \
458   R##_s = X##_s ^ Y##_s;                                \
459   switch (_FP_CLS_COMBINE(X##_c, Y##_c))                \
460   {                                                     \
461   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_NORMAL):    \
462     R##_c = FP_CLS_NORMAL;                              \
463     R##_e = X##_e - Y##_e;                              \
464                                                         \
465     _FP_DIV_MEAT_##fs(R,X,Y);                           \
466     break;                                              \
467                                                         \
468   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_NAN):          \
469     _FP_CHOOSENAN(fs, wc, R, X, Y, '/');                \
470     break;                                              \
471                                                         \
472   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_NORMAL):       \
473   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_INF):          \
474   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_ZERO):         \
475     R##_s = X##_s;                                      \
476     _FP_FRAC_COPY_##wc(R, X);                           \
477     R##_c = X##_c;                                      \
478     break;                                              \
479                                                         \
480   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_NAN):       \
481   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_NAN):          \
482   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_NAN):         \
483     R##_s = Y##_s;                                      \
484     _FP_FRAC_COPY_##wc(R, Y);                           \
485     R##_c = Y##_c;                                      \
486     break;                                              \
487                                                         \
488   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_INF):       \
489   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_INF):         \
490   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_NORMAL):      \
491     R##_c = FP_CLS_ZERO;                                \
492     break;                                              \
493                                                         \
494   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_ZERO):      \
495     FP_SET_EXCEPTION(FP_EX_DIVZERO);                    \
496   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_ZERO):         \
497   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_NORMAL):       \
498     R##_c = FP_CLS_INF;                                 \
499     break;                                              \
500                                                         \
501   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_INF):          \
502     R##_s = _FP_NANSIGN_##fs;                           \
503     R##_c = FP_CLS_NAN;                                 \
504     _FP_FRAC_SET_##wc(R, _FP_NANFRAC_##fs);             \
505     FP_SET_EXCEPTION(FP_EX_INVALID | FP_EX_INVALID_IDI);\
506     break;                                              \
507                                                         \
508   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_ZERO):        \
509     R##_s = _FP_NANSIGN_##fs;                           \
510     R##_c = FP_CLS_NAN;                                 \
511     _FP_FRAC_SET_##wc(R, _FP_NANFRAC_##fs);             \
512     FP_SET_EXCEPTION(FP_EX_INVALID | FP_EX_INVALID_ZDZ);\
513     break;                                              \
514                                                         \
515   default:                                              \
516     abort();                                            \
517   }                                                     \
518 } while (0)
519
520
521 /*
522  * Main differential comparison routine.  The inputs should be raw not
523  * cooked.  The return is -1,0,1 for normal values, 2 otherwise.
524  */
525
526 #define _FP_CMP(fs, wc, ret, X, Y, un)                                  \
527   do {                                                                  \
528     /* NANs are unordered */                                            \
529     if ((X##_e == _FP_EXPMAX_##fs && !_FP_FRAC_ZEROP_##wc(X))           \
530         || (Y##_e == _FP_EXPMAX_##fs && !_FP_FRAC_ZEROP_##wc(Y)))       \
531       {                                                                 \
532         ret = un;                                                       \
533       }                                                                 \
534     else                                                                \
535       {                                                                 \
536         int __is_zero_x;                                                \
537         int __is_zero_y;                                                \
538                                                                         \
539         __is_zero_x = (!X##_e && _FP_FRAC_ZEROP_##wc(X)) ? 1 : 0;       \
540         __is_zero_y = (!Y##_e && _FP_FRAC_ZEROP_##wc(Y)) ? 1 : 0;       \
541                                                                         \
542         if (__is_zero_x && __is_zero_y)                                 \
543                 ret = 0;                                                \
544         else if (__is_zero_x)                                           \
545                 ret = Y##_s ? 1 : -1;                                   \
546         else if (__is_zero_y)                                           \
547                 ret = X##_s ? -1 : 1;                                   \
548         else if (X##_s != Y##_s)                                        \
549           ret = X##_s ? -1 : 1;                                         \
550         else if (X##_e > Y##_e)                                         \
551           ret = X##_s ? -1 : 1;                                         \
552         else if (X##_e < Y##_e)                                         \
553           ret = X##_s ? 1 : -1;                                         \
554         else if (_FP_FRAC_GT_##wc(X, Y))                                \
555           ret = X##_s ? -1 : 1;                                         \
556         else if (_FP_FRAC_GT_##wc(Y, X))                                \
557           ret = X##_s ? 1 : -1;                                         \
558         else                                                            \
559           ret = 0;                                                      \
560       }                                                                 \
561   } while (0)
562
563
564 /* Simplification for strict equality.  */
565
566 #define _FP_CMP_EQ(fs, wc, ret, X, Y)                                     \
567   do {                                                                    \
568     /* NANs are unordered */                                              \
569     if ((X##_e == _FP_EXPMAX_##fs && !_FP_FRAC_ZEROP_##wc(X))             \
570         || (Y##_e == _FP_EXPMAX_##fs && !_FP_FRAC_ZEROP_##wc(Y)))         \
571       {                                                                   \
572         ret = 1;                                                          \
573       }                                                                   \
574     else                                                                  \
575       {                                                                   \
576         ret = !(X##_e == Y##_e                                            \
577                 && _FP_FRAC_EQ_##wc(X, Y)                                 \
578                 && (X##_s == Y##_s || !X##_e && _FP_FRAC_ZEROP_##wc(X))); \
579       }                                                                   \
580   } while (0)
581
582 /*
583  * Main square root routine.  The input value should be cooked.
584  */
585
586 #define _FP_SQRT(fs, wc, R, X)                                          \
587 do {                                                                    \
588     _FP_FRAC_DECL_##wc(T); _FP_FRAC_DECL_##wc(S);                       \
589     _FP_W_TYPE q;                                                       \
590     switch (X##_c)                                                      \
591     {                                                                   \
592     case FP_CLS_NAN:                                                    \
593         _FP_FRAC_COPY_##wc(R, X);                                       \
594         R##_s = X##_s;                                                  \
595         R##_c = FP_CLS_NAN;                                             \
596         break;                                                          \
597     case FP_CLS_INF:                                                    \
598         if (X##_s)                                                      \
599           {                                                             \
600             R##_s = _FP_NANSIGN_##fs;                                   \
601             R##_c = FP_CLS_NAN; /* NAN */                               \
602             _FP_FRAC_SET_##wc(R, _FP_NANFRAC_##fs);                     \
603             FP_SET_EXCEPTION(FP_EX_INVALID);                            \
604           }                                                             \
605         else                                                            \
606           {                                                             \
607             R##_s = 0;                                                  \
608             R##_c = FP_CLS_INF; /* sqrt(+inf) = +inf */                 \
609           }                                                             \
610         break;                                                          \
611     case FP_CLS_ZERO:                                                   \
612         R##_s = X##_s;                                                  \
613         R##_c = FP_CLS_ZERO; /* sqrt(+-0) = +-0 */                      \
614         break;                                                          \
615     case FP_CLS_NORMAL:                                                 \
616         R##_s = 0;                                                      \
617         if (X##_s)                                                      \
618           {                                                             \
619             R##_c = FP_CLS_NAN; /* sNAN */                              \
620             R##_s = _FP_NANSIGN_##fs;                                   \
621             _FP_FRAC_SET_##wc(R, _FP_NANFRAC_##fs);                     \
622             FP_SET_EXCEPTION(FP_EX_INVALID);                            \
623             break;                                                      \
624           }                                                             \
625         R##_c = FP_CLS_NORMAL;                                          \
626         if (X##_e & 1)                                                  \
627           _FP_FRAC_SLL_##wc(X, 1);                                      \
628         R##_e = X##_e >> 1;                                             \
629         _FP_FRAC_SET_##wc(S, _FP_ZEROFRAC_##wc);                        \
630         _FP_FRAC_SET_##wc(R, _FP_ZEROFRAC_##wc);                        \
631         q = _FP_OVERFLOW_##fs >> 1;                                     \
632         _FP_SQRT_MEAT_##wc(R, S, T, X, q);                              \
633     }                                                                   \
634   } while (0)
635
636 /*
637  * Convert from FP to integer
638  */
639
640 /* RSIGNED can have following values:
641  * 0:  the number is required to be 0..(2^rsize)-1, if not, NV is set plus
642  *     the result is either 0 or (2^rsize)-1 depending on the sign in such case.
643  * 1:  the number is required to be -(2^(rsize-1))..(2^(rsize-1))-1, if not, NV is
644  *     set plus the result is either -(2^(rsize-1)) or (2^(rsize-1))-1 depending
645  *     on the sign in such case.
646  * 2:  the number is required to be -(2^(rsize-1))..(2^(rsize-1))-1, if not, NV is
647  *     set plus the result is truncated to fit into destination.
648  * -1: the number is required to be -(2^(rsize-1))..(2^rsize)-1, if not, NV is
649  *     set plus the result is either -(2^(rsize-1)) or (2^(rsize-1))-1 depending
650  *     on the sign in such case.
651  */
652 #define _FP_TO_INT(fs, wc, r, X, rsize, rsigned)                                \
653   do {                                                                          \
654     switch (X##_c)                                                              \
655       {                                                                         \
656       case FP_CLS_NORMAL:                                                       \
657         if (X##_e < 0)                                                          \
658           {                                                                     \
659             FP_SET_EXCEPTION(FP_EX_INEXACT);                                    \
660           case FP_CLS_ZERO:                                                     \
661             r = 0;                                                              \
662           }                                                                     \
663         else if (X##_e >= rsize - (rsigned > 0 || X##_s)                        \
664                  || (!rsigned && X##_s))                                        \
665           {     /* overflow */                                                  \
666           case FP_CLS_NAN:                                                      \
667           case FP_CLS_INF:                                                      \
668             if (rsigned == 2)                                                   \
669               {                                                                 \
670                 if (X##_c != FP_CLS_NORMAL                                      \
671                     || X##_e >= rsize - 1 + _FP_WFRACBITS_##fs)                 \
672                   r = 0;                                                        \
673                 else                                                            \
674                   {                                                             \
675                     _FP_FRAC_SLL_##wc(X, (X##_e - _FP_WFRACBITS_##fs + 1));     \
676                     _FP_FRAC_ASSEMBLE_##wc(r, X, rsize);                        \
677                   }                                                             \
678               }                                                                 \
679             else if (rsigned)                                                   \
680               {                                                                 \
681                 r = 1;                                                          \
682                 r <<= rsize - 1;                                                \
683                 r -= 1 - X##_s;                                                 \
684               }                                                                 \
685             else                                                                \
686               {                                                                 \
687                 r = 0;                                                          \
688                 if (X##_s)                                                      \
689                   r = ~r;                                                       \
690               }                                                                 \
691             FP_SET_EXCEPTION(FP_EX_INVALID);                                    \
692           }                                                                     \
693         else                                                                    \
694           {                                                                     \
695             if (_FP_W_TYPE_SIZE*wc < rsize)                                     \
696               {                                                                 \
697                 _FP_FRAC_ASSEMBLE_##wc(r, X, rsize);                            \
698                 r <<= X##_e - _FP_WFRACBITS_##fs;                               \
699               }                                                                 \
700             else                                                                \
701               {                                                                 \
702                 if (X##_e >= _FP_WFRACBITS_##fs)                                \
703                   _FP_FRAC_SLL_##wc(X, (X##_e - _FP_WFRACBITS_##fs + 1));       \
704                 else if (X##_e < _FP_WFRACBITS_##fs - 1)                        \
705                   {                                                             \
706                     _FP_FRAC_SRS_##wc(X, (_FP_WFRACBITS_##fs - X##_e - 2),      \
707                                       _FP_WFRACBITS_##fs);                      \
708                     if (_FP_FRAC_LOW_##wc(X) & 1)                               \
709                       FP_SET_EXCEPTION(FP_EX_INEXACT);                          \
710                     _FP_FRAC_SRL_##wc(X, 1);                                    \
711                   }                                                             \
712                 _FP_FRAC_ASSEMBLE_##wc(r, X, rsize);                            \
713               }                                                                 \
714             if (rsigned && X##_s)                                               \
715               r = -r;                                                           \
716           }                                                                     \
717         break;                                                                  \
718       }                                                                         \
719   } while (0)
720
721 #define _FP_TO_INT_ROUND(fs, wc, r, X, rsize, rsigned)                          \
722   do {                                                                          \
723     r = 0;                                                                      \
724     switch (X##_c)                                                              \
725       {                                                                         \
726       case FP_CLS_NORMAL:                                                       \
727         if (X##_e >= _FP_FRACBITS_##fs - 1)                                     \
728           {                                                                     \
729             if (X##_e < rsize - 1 + _FP_WFRACBITS_##fs)                         \
730               {                                                                 \
731                 if (X##_e >= _FP_WFRACBITS_##fs - 1)                            \
732                   {                                                             \
733                     _FP_FRAC_ASSEMBLE_##wc(r, X, rsize);                        \
734                     r <<= X##_e - _FP_WFRACBITS_##fs + 1;                       \
735                   }                                                             \
736                 else                                                            \
737                   {                                                             \
738                     _FP_FRAC_SRL_##wc(X, _FP_WORKBITS - X##_e                   \
739                                       + _FP_FRACBITS_##fs - 1);                 \
740                     _FP_FRAC_ASSEMBLE_##wc(r, X, rsize);                        \
741                   }                                                             \
742               }                                                                 \
743           }                                                                     \
744         else                                                                    \
745           {                                                                     \
746             if (X##_e <= -_FP_WORKBITS - 1)                                     \
747               _FP_FRAC_SET_##wc(X, _FP_MINFRAC_##wc);                           \
748             else                                                                \
749               _FP_FRAC_SRS_##wc(X, _FP_FRACBITS_##fs - 1 - X##_e,               \
750                                 _FP_WFRACBITS_##fs);                            \
751             _FP_ROUND(wc, X);                                                   \
752             _FP_FRAC_SRL_##wc(X, _FP_WORKBITS);                                 \
753             _FP_FRAC_ASSEMBLE_##wc(r, X, rsize);                                \
754           }                                                                     \
755         if (rsigned && X##_s)                                                   \
756           r = -r;                                                               \
757         if (X##_e >= rsize - (rsigned > 0 || X##_s)                             \
758             || (!rsigned && X##_s))                                             \
759           {     /* overflow */                                                  \
760           case FP_CLS_NAN:                                                      \
761           case FP_CLS_INF:                                                      \
762             if (!rsigned)                                                       \
763               {                                                                 \
764                 r = 0;                                                          \
765                 if (X##_s)                                                      \
766                   r = ~r;                                                       \
767               }                                                                 \
768             else if (rsigned != 2)                                              \
769               {                                                                 \
770                 r = 1;                                                          \
771                 r <<= rsize - 1;                                                \
772                 r -= 1 - X##_s;                                                 \
773               }                                                                 \
774             FP_SET_EXCEPTION(FP_EX_INVALID);                                    \
775           }                                                                     \
776         break;                                                                  \
777       case FP_CLS_ZERO:                                                         \
778         break;                                                                  \
779       }                                                                         \
780   } while (0)
781
782 #define _FP_FROM_INT(fs, wc, X, r, rsize, rtype)                        \
783   do {                                                                  \
784     if (r)                                                              \
785       {                                                                 \
786         unsigned rtype ur_;                                             \
787         X##_c = FP_CLS_NORMAL;                                          \
788                                                                         \
789         if ((X##_s = (r < 0)))                                          \
790           ur_ = (unsigned rtype) -r;                                    \
791         else                                                            \
792           ur_ = (unsigned rtype) r;                                     \
793         if (rsize <= _FP_W_TYPE_SIZE)                                   \
794           __FP_CLZ(X##_e, ur_);                                         \
795         else                                                            \
796           __FP_CLZ_2(X##_e, (_FP_W_TYPE)(ur_ >> _FP_W_TYPE_SIZE),       \
797                      (_FP_W_TYPE)ur_);                                  \
798         if (rsize < _FP_W_TYPE_SIZE)                                    \
799                 X##_e -= (_FP_W_TYPE_SIZE - rsize);                     \
800         X##_e = rsize - X##_e - 1;                                      \
801                                                                         \
802         if (_FP_FRACBITS_##fs < rsize && _FP_WFRACBITS_##fs <= X##_e)   \
803           __FP_FRAC_SRS_1(ur_, (X##_e - _FP_WFRACBITS_##fs + 1), rsize);\
804         _FP_FRAC_DISASSEMBLE_##wc(X, ur_, rsize);                       \
805         if ((_FP_WFRACBITS_##fs - X##_e - 1) > 0)                       \
806           _FP_FRAC_SLL_##wc(X, (_FP_WFRACBITS_##fs - X##_e - 1));       \
807       }                                                                 \
808     else                                                                \
809       {                                                                 \
810         X##_c = FP_CLS_ZERO, X##_s = 0;                                 \
811       }                                                                 \
812   } while (0)
813
814
815 #define FP_CONV(dfs,sfs,dwc,swc,D,S)                    \
816   do {                                                  \
817     _FP_FRAC_CONV_##dwc##_##swc(dfs, sfs, D, S);        \
818     D##_e = S##_e;                                      \
819     D##_c = S##_c;                                      \
820     D##_s = S##_s;                                      \
821   } while (0)
822
823 /*
824  * Helper primitives.
825  */
826
827 /* Count leading zeros in a word.  */
828
829 #ifndef __FP_CLZ
830 #if _FP_W_TYPE_SIZE < 64
831 /* this is just to shut the compiler up about shifts > word length -- PMM 02/1998 */
832 #define __FP_CLZ(r, x)                          \
833   do {                                          \
834     _FP_W_TYPE _t = (x);                        \
835     r = _FP_W_TYPE_SIZE - 1;                    \
836     if (_t > 0xffff) r -= 16;                   \
837     if (_t > 0xffff) _t >>= 16;                 \
838     if (_t > 0xff) r -= 8;                      \
839     if (_t > 0xff) _t >>= 8;                    \
840     if (_t & 0xf0) r -= 4;                      \
841     if (_t & 0xf0) _t >>= 4;                    \
842     if (_t & 0xc) r -= 2;                       \
843     if (_t & 0xc) _t >>= 2;                     \
844     if (_t & 0x2) r -= 1;                       \
845   } while (0)
846 #else /* not _FP_W_TYPE_SIZE < 64 */
847 #define __FP_CLZ(r, x)                          \
848   do {                                          \
849     _FP_W_TYPE _t = (x);                        \
850     r = _FP_W_TYPE_SIZE - 1;                    \
851     if (_t > 0xffffffff) r -= 32;               \
852     if (_t > 0xffffffff) _t >>= 32;             \
853     if (_t > 0xffff) r -= 16;                   \
854     if (_t > 0xffff) _t >>= 16;                 \
855     if (_t > 0xff) r -= 8;                      \
856     if (_t > 0xff) _t >>= 8;                    \
857     if (_t & 0xf0) r -= 4;                      \
858     if (_t & 0xf0) _t >>= 4;                    \
859     if (_t & 0xc) r -= 2;                       \
860     if (_t & 0xc) _t >>= 2;                     \
861     if (_t & 0x2) r -= 1;                       \
862   } while (0)
863 #endif /* not _FP_W_TYPE_SIZE < 64 */
864 #endif /* ndef __FP_CLZ */
865
866 #define _FP_DIV_HELP_imm(q, r, n, d)            \
867   do {                                          \
868     q = n / d, r = n % d;                       \
869   } while (0)
870
871 #endif /* __MATH_EMU_OP_COMMON_H__ */