Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland...
[linux-2.6] / arch / parisc / math-emu / cnv_float.h
1 /*
2  * Linux/PA-RISC Project (http://www.parisc-linux.org/)
3  *
4  * Floating-point emulation code
5  *  Copyright (C) 2001 Hewlett-Packard (Paul Bame) <bame@debian.org>
6  *
7  *    This program is free software; you can redistribute it and/or modify
8  *    it under the terms of the GNU General Public License as published by
9  *    the Free Software Foundation; either version 2, or (at your option)
10  *    any later version.
11  *
12  *    This program is distributed in the hope that it will be useful,
13  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *    GNU General Public License for more details.
16  *
17  *    You should have received a copy of the GNU General Public License
18  *    along with this program; if not, write to the Free Software
19  *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
20  */
21
22 #ifdef __NO_PA_HDRS
23     PA header file -- do not include this header file for non-PA builds.
24 #endif
25
26 /*
27  * Some more constants
28  */
29 #define SGL_FX_MAX_EXP 30
30 #define DBL_FX_MAX_EXP 62
31 #define QUAD_FX_MAX_EXP 126
32
33 #define Dintp1(object) (object)
34 #define Dintp2(object) (object)
35
36 #define Duintp1(object) (object)
37 #define Duintp2(object) (object)
38
39 #define Qintp0(object) (object)
40 #define Qintp1(object) (object)
41 #define Qintp2(object) (object)
42 #define Qintp3(object) (object)
43
44
45 /*
46  * These macros will be used specifically by the convert instructions.
47  *
48  *
49  * Single format macros
50  */
51
52 #define Sgl_to_dbl_exponent(src_exponent,dest)                  \
53     Deposit_dexponent(dest,src_exponent+(DBL_BIAS-SGL_BIAS))
54
55 #define Sgl_to_dbl_mantissa(src_mantissa,destA,destB)   \
56     Deposit_dmantissap1(destA,src_mantissa>>3);         \
57     Dmantissap2(destB) = src_mantissa << 29
58
59 #define Sgl_isinexact_to_fix(sgl_value,exponent)        \
60     ((exponent < (SGL_P - 1)) ?                         \
61      (Sall(sgl_value) << (SGL_EXP_LENGTH + 1 + exponent)) : FALSE)
62
63 #define Int_isinexact_to_sgl(int_value) (int_value << 33 - SGL_EXP_LENGTH)
64
65 #define Sgl_roundnearest_from_int(int_value,sgl_value)                  \
66     if (int_value & 1<<(SGL_EXP_LENGTH - 2))   /* round bit */          \
67         if ((int_value << 34 - SGL_EXP_LENGTH) || Slow(sgl_value))      \
68                 Sall(sgl_value)++
69
70 #define Dint_isinexact_to_sgl(dint_valueA,dint_valueB)          \
71     ((Dintp1(dint_valueA) << 33 - SGL_EXP_LENGTH) || Dintp2(dint_valueB))
72
73 #define Sgl_roundnearest_from_dint(dint_valueA,dint_valueB,sgl_value)   \
74     if (Dintp1(dint_valueA) & 1<<(SGL_EXP_LENGTH - 2))                  \
75         if ((Dintp1(dint_valueA) << 34 - SGL_EXP_LENGTH) ||             \
76         Dintp2(dint_valueB) || Slow(sgl_value)) Sall(sgl_value)++
77
78 #define Dint_isinexact_to_dbl(dint_value)       \
79     (Dintp2(dint_value) << 33 - DBL_EXP_LENGTH)
80
81 #define Dbl_roundnearest_from_dint(dint_opndB,dbl_opndA,dbl_opndB)      \
82     if (Dintp2(dint_opndB) & 1<<(DBL_EXP_LENGTH - 2))                   \
83        if ((Dintp2(dint_opndB) << 34 - DBL_EXP_LENGTH) || Dlowp2(dbl_opndB))  \
84           if ((++Dallp2(dbl_opndB))==0) Dallp1(dbl_opndA)++
85
86 #define Sgl_isone_roundbit(sgl_value,exponent)                  \
87     ((Sall(sgl_value) << (SGL_EXP_LENGTH + 1 + exponent)) >> 31)
88
89 #define Sgl_isone_stickybit(sgl_value,exponent)         \
90     (exponent < (SGL_P - 2) ?                           \
91      Sall(sgl_value) << (SGL_EXP_LENGTH + 2 + exponent) : FALSE)
92
93
94 /* 
95  * Double format macros
96  */
97
98 #define Dbl_to_sgl_exponent(src_exponent,dest)                  \
99     dest = src_exponent + (SGL_BIAS - DBL_BIAS)
100
101 #define Dbl_to_sgl_mantissa(srcA,srcB,dest,inexact,guard,sticky,odd)    \
102     Shiftdouble(Dmantissap1(srcA),Dmantissap2(srcB),29,dest);   \
103     guard = Dbit3p2(srcB);                                      \
104     sticky = Dallp2(srcB)<<4;                                   \
105     inexact = guard | sticky;                                   \
106     odd = Dbit2p2(srcB)
107
108 #define Dbl_to_sgl_denormalized(srcA,srcB,exp,dest,inexact,guard,sticky,odd,tiny) \
109     Deposit_dexponent(srcA,1);                                          \
110     tiny = TRUE;                                                        \
111     if (exp >= -2) {                                                    \
112         if (exp == 0) {                                                 \
113             inexact = Dallp2(srcB) << 3;                                \
114             guard = inexact >> 31;                                      \
115             sticky = inexact << 1;                                      \
116             Shiftdouble(Dmantissap1(srcA),Dmantissap2(srcB),29,dest);   \
117             odd = dest << 31;                                           \
118             if (inexact) {                                              \
119                 switch(Rounding_mode()) {                               \
120                     case ROUNDPLUS:                                     \
121                         if (Dbl_iszero_sign(srcA)) {                    \
122                             dest++;                                     \
123                             if (Sgl_isone_hidden(dest)) \
124                                 tiny = FALSE;                           \
125                             dest--;                                     \
126                         }                                               \
127                         break;                                          \
128                     case ROUNDMINUS:                                    \
129                         if (Dbl_isone_sign(srcA)) {                     \
130                             dest++;                                     \
131                             if (Sgl_isone_hidden(dest)) \
132                                 tiny = FALSE;                           \
133                             dest--;                                     \
134                         }                                               \
135                         break;                                          \
136                     case ROUNDNEAREST:                                  \
137                         if (guard && (sticky || odd)) {                 \
138                             dest++;                                     \
139                             if (Sgl_isone_hidden(dest)) \
140                                 tiny = FALSE;                           \
141                             dest--;                                     \
142                         }                                               \
143                         break;                                          \
144                 }                                                       \
145             }                                                           \
146                 /* shift right by one to get correct result */          \
147                 guard = odd;                                            \
148                 sticky = inexact;                                       \
149                 inexact |= guard;                                       \
150                 dest >>= 1;                                             \
151                 Deposit_dsign(srcA,0);                                  \
152                 Shiftdouble(Dallp1(srcA),Dallp2(srcB),30,dest);         \
153                 odd = dest << 31;                                       \
154         }                                                               \
155         else {                                                          \
156             inexact = Dallp2(srcB) << (2 + exp);                        \
157             guard = inexact >> 31;                                      \
158             sticky = inexact << 1;                                      \
159             Deposit_dsign(srcA,0);                                      \
160             if (exp == -2) dest = Dallp1(srcA);                         \
161             else Variable_shift_double(Dallp1(srcA),Dallp2(srcB),30-exp,dest); \
162             odd = dest << 31;                                           \
163         }                                                               \
164     }                                                                   \
165     else {                                                              \
166         Deposit_dsign(srcA,0);                                          \
167         if (exp > (1 - SGL_P)) {                                        \
168             dest = Dallp1(srcA) >> (- 2 - exp);                         \
169             inexact = Dallp1(srcA) << (34 + exp);                       \
170             guard = inexact >> 31;                                      \
171             sticky = (inexact << 1) | Dallp2(srcB);                     \
172             inexact |= Dallp2(srcB);                                    \
173             odd = dest << 31;                                           \
174         }                                                               \
175         else {                                                          \
176             dest = 0;                                                   \
177             inexact = Dallp1(srcA) | Dallp2(srcB);                      \
178             if (exp == (1 - SGL_P)) {                                   \
179                 guard = Dhidden(srcA);                                  \
180                 sticky = Dmantissap1(srcA) | Dallp2(srcB);              \
181             }                                                           \
182             else {                                                      \
183                 guard = 0;                                              \
184                 sticky = inexact;                                       \
185             }                                                           \
186             odd = 0;                                                    \
187         }                                                               \
188     }                                                                   \
189     exp = 0
190
191 #define Dbl_isinexact_to_fix(dbl_valueA,dbl_valueB,exponent)            \
192     (exponent < (DBL_P-33) ?                                            \
193      Dallp2(dbl_valueB) || Dallp1(dbl_valueA) << (DBL_EXP_LENGTH+1+exponent) : \
194      (exponent < (DBL_P-1) ? Dallp2(dbl_valueB) << (exponent + (33-DBL_P)) :   \
195       FALSE))
196
197 #define Dbl_isoverflow_to_int(exponent,dbl_valueA,dbl_valueB)           \
198     ((exponent > SGL_FX_MAX_EXP + 1) || Dsign(dbl_valueA)==0 ||         \
199      Dmantissap1(dbl_valueA)!=0 || (Dallp2(dbl_valueB)>>21)!=0 ) 
200
201 #define Dbl_isone_roundbit(dbl_valueA,dbl_valueB,exponent)              \
202     ((exponent < (DBL_P - 33) ?                                         \
203       Dallp1(dbl_valueA) >> ((30 - DBL_EXP_LENGTH) - exponent) :        \
204       Dallp2(dbl_valueB) >> ((DBL_P - 2) - exponent)) & 1)
205
206 #define Dbl_isone_stickybit(dbl_valueA,dbl_valueB,exponent)             \
207     (exponent < (DBL_P-34) ?                                            \
208      (Dallp2(dbl_valueB) || Dallp1(dbl_valueA)<<(DBL_EXP_LENGTH+2+exponent)) : \
209      (exponent<(DBL_P-2) ? (Dallp2(dbl_valueB) << (exponent + (34-DBL_P))) : \
210       FALSE))
211
212
213 /* Int macros */
214
215 #define Int_from_sgl_mantissa(sgl_value,exponent)       \
216     Sall(sgl_value) =                           \
217         (unsigned)(Sall(sgl_value) << SGL_EXP_LENGTH)>>(31 - exponent)
218
219 #define Int_from_dbl_mantissa(dbl_valueA,dbl_valueB,exponent)   \
220     Shiftdouble(Dallp1(dbl_valueA),Dallp2(dbl_valueB),22,Dallp1(dbl_valueA)); \
221     if (exponent < 31) Dallp1(dbl_valueA) >>= 30 - exponent;    \
222     else Dallp1(dbl_valueA) <<= 1
223
224 #define Int_negate(int_value) int_value = -int_value
225
226
227 /* Dint macros */
228
229 #define Dint_from_sgl_mantissa(sgl_value,exponent,dresultA,dresultB)    \
230     {Sall(sgl_value) <<= SGL_EXP_LENGTH;  /*  left-justify  */          \
231     if (exponent <= 31) {                                               \
232         Dintp1(dresultA) = 0;                                           \
233         Dintp2(dresultB) = (unsigned)Sall(sgl_value) >> (31 - exponent); \
234     }                                                                   \
235     else {                                                              \
236         Dintp1(dresultA) = Sall(sgl_value) >> (63 - exponent);          \
237         Dintp2(dresultB) = Sall(sgl_value) << (exponent - 31);          \
238     }}
239
240
241 #define Dint_from_dbl_mantissa(dbl_valueA,dbl_valueB,exponent,destA,destB) \
242     {if (exponent < 32) {                                               \
243         Dintp1(destA) = 0;                                              \
244         if (exponent <= 20)                                             \
245             Dintp2(destB) = Dallp1(dbl_valueA) >> 20-exponent;          \
246         else Variable_shift_double(Dallp1(dbl_valueA),Dallp2(dbl_valueB), \
247              52-exponent,Dintp2(destB));                                        \
248     }                                                                   \
249     else {                                                              \
250         if (exponent <= 52) {                                           \
251             Dintp1(destA) = Dallp1(dbl_valueA) >> 52-exponent;          \
252             if (exponent == 52) Dintp2(destB) = Dallp2(dbl_valueB);     \
253             else Variable_shift_double(Dallp1(dbl_valueA),Dallp2(dbl_valueB), \
254             52-exponent,Dintp2(destB));                                 \
255         }                                                               \
256         else {                                                          \
257             Variable_shift_double(Dallp1(dbl_valueA),Dallp2(dbl_valueB), \
258             84-exponent,Dintp1(destA));                                 \
259             Dintp2(destB) = Dallp2(dbl_valueB) << exponent-52;          \
260         }                                                               \
261     }}
262
263 #define Dint_setzero(dresultA,dresultB)         \
264     Dintp1(dresultA) = 0;       \
265     Dintp2(dresultB) = 0
266
267 #define Dint_setone_sign(dresultA,dresultB)             \
268     Dintp1(dresultA) = ~Dintp1(dresultA);               \
269     if ((Dintp2(dresultB) = -Dintp2(dresultB)) == 0) Dintp1(dresultA)++
270
271 #define Dint_set_minint(dresultA,dresultB)              \
272     Dintp1(dresultA) = (unsigned int)1<<31;             \
273     Dintp2(dresultB) = 0
274
275 #define Dint_isone_lowp2(dresultB)  (Dintp2(dresultB) & 01)
276
277 #define Dint_increment(dresultA,dresultB)               \
278     if ((++Dintp2(dresultB))==0) Dintp1(dresultA)++
279
280 #define Dint_decrement(dresultA,dresultB)               \
281     if ((Dintp2(dresultB)--)==0) Dintp1(dresultA)--
282
283 #define Dint_negate(dresultA,dresultB)                  \
284     Dintp1(dresultA) = ~Dintp1(dresultA);               \
285     if ((Dintp2(dresultB) = -Dintp2(dresultB))==0) Dintp1(dresultA)++
286
287 #define Dint_copyfromptr(src,destA,destB) \
288      Dintp1(destA) = src->wd0;          \
289      Dintp2(destB) = src->wd1
290 #define Dint_copytoptr(srcA,srcB,dest)  \
291     dest->wd0 = Dintp1(srcA);           \
292     dest->wd1 = Dintp2(srcB)
293
294
295 /* other macros  */
296
297 #define Find_ms_one_bit(value, position)        \
298     {                                           \
299         int var;                                \
300         for (var=8; var >=1; var >>= 1) {       \
301             if (value >> 32 - position)         \
302                 position -= var;                \
303                 else position += var;           \
304         }                                       \
305         if ((value >> 32 - position) == 0)      \
306             position--;                         \
307         else position -= 2;                     \
308     }
309
310
311 /*
312  * Unsigned int macros
313  */
314 #define Duint_copyfromptr(src,destA,destB) \
315     Dint_copyfromptr(src,destA,destB)
316 #define Duint_copytoptr(srcA,srcB,dest) \
317     Dint_copytoptr(srcA,srcB,dest)
318
319 #define Suint_isinexact_to_sgl(int_value) \
320     (int_value << 32 - SGL_EXP_LENGTH)
321
322 #define Sgl_roundnearest_from_suint(suint_value,sgl_value)              \
323     if (suint_value & 1<<(SGL_EXP_LENGTH - 1))   /* round bit */        \
324         if ((suint_value << 33 - SGL_EXP_LENGTH) || Slow(sgl_value))    \
325                 Sall(sgl_value)++
326
327 #define Duint_isinexact_to_sgl(duint_valueA,duint_valueB)       \
328     ((Duintp1(duint_valueA) << 32 - SGL_EXP_LENGTH) || Duintp2(duint_valueB))
329
330 #define Sgl_roundnearest_from_duint(duint_valueA,duint_valueB,sgl_value) \
331     if (Duintp1(duint_valueA) & 1<<(SGL_EXP_LENGTH - 1))                \
332         if ((Duintp1(duint_valueA) << 33 - SGL_EXP_LENGTH) ||           \
333         Duintp2(duint_valueB) || Slow(sgl_value)) Sall(sgl_value)++
334
335 #define Duint_isinexact_to_dbl(duint_value)     \
336     (Duintp2(duint_value) << 32 - DBL_EXP_LENGTH)
337
338 #define Dbl_roundnearest_from_duint(duint_opndB,dbl_opndA,dbl_opndB)    \
339     if (Duintp2(duint_opndB) & 1<<(DBL_EXP_LENGTH - 1))                 \
340        if ((Duintp2(duint_opndB) << 33 - DBL_EXP_LENGTH) || Dlowp2(dbl_opndB)) \
341           if ((++Dallp2(dbl_opndB))==0) Dallp1(dbl_opndA)++
342
343 #define Suint_from_sgl_mantissa(src,exponent,result)    \
344     Sall(result) = (unsigned)(Sall(src) << SGL_EXP_LENGTH)>>(31 - exponent)
345
346 #define Sgl_isinexact_to_unsigned(sgl_value,exponent)   \
347     Sgl_isinexact_to_fix(sgl_value,exponent)
348
349 #define Duint_from_sgl_mantissa(sgl_value,exponent,dresultA,dresultB)   \
350   {Sall(sgl_value) <<= SGL_EXP_LENGTH;  /*  left-justify  */            \
351     if (exponent <= 31) {                                               \
352         Dintp1(dresultA) = 0;                                           \
353         Dintp2(dresultB) = (unsigned)Sall(sgl_value) >> (31 - exponent); \
354     }                                                                   \
355     else {                                                              \
356         Dintp1(dresultA) = Sall(sgl_value) >> (63 - exponent);          \
357         Dintp2(dresultB) = Sall(sgl_value) << (exponent - 31);          \
358     }                                                                   \
359     Sall(sgl_value) >>= SGL_EXP_LENGTH;  /* return to original */       \
360   }
361
362 #define Duint_setzero(dresultA,dresultB)        \
363     Dint_setzero(dresultA,dresultB)
364
365 #define Duint_increment(dresultA,dresultB) Dint_increment(dresultA,dresultB) 
366
367 #define Duint_isone_lowp2(dresultB)  Dint_isone_lowp2(dresultB)
368
369 #define Suint_from_dbl_mantissa(srcA,srcB,exponent,dest) \
370     Shiftdouble(Dallp1(srcA),Dallp2(srcB),21,dest); \
371     dest = (unsigned)dest >> 31 - exponent
372
373 #define Dbl_isinexact_to_unsigned(dbl_valueA,dbl_valueB,exponent) \
374     Dbl_isinexact_to_fix(dbl_valueA,dbl_valueB,exponent)
375
376 #define Duint_from_dbl_mantissa(dbl_valueA,dbl_valueB,exponent,destA,destB) \
377     Dint_from_dbl_mantissa(dbl_valueA,dbl_valueB,exponent,destA,destB)