1 /*
2 * MIPS floating point support
3 * Copyright (C) 1994-2000 Algorithmics Ltd.
4 * http://www.algor.co.uk
5 *
6 * This program is free software; you can distribute it and/or modify it
7 * under the terms of the GNU General Public License (Version 2) as
8 * published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * for more details.
14 *
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
18 *
19 * Nov 7, 2000
20 * Modification to allow integration with Linux kernel
21 *
22 * Kevin D. Kissell, kevink@mips.com and Carsten Langgard, carstenl@mips.com
23 * Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved.
24 */
25 #ifndef __ARCH_MIPS_MATH_EMU_IEEE754_H
26 #define __ARCH_MIPS_MATH_EMU_IEEE754_H
27
28 #include <asm/byteorder.h>
29 #include <linux/types.h>
30 #include <linux/sched.h>
31
32 /*
33 * Not very pretty, but the Linux kernel's normal va_list definition
34 * does not allow it to be used as a structure element, as it is here.
35 */
36 #ifndef _STDARG_H
37 #include <stdarg.h>
38 #endif
39
40 #ifdef __LITTLE_ENDIAN
41 struct ieee754dp_konst {
42 unsigned mantlo:32;
43 unsigned manthi:20;
44 unsigned bexp:11;
45 unsigned sign:1;
46 };
47 struct ieee754sp_konst {
48 unsigned mant:23;
49 unsigned bexp:8;
50 unsigned sign:1;
51 };
52
53 typedef union _ieee754dp {
54 struct ieee754dp_konst oparts;
55 struct {
56 u64 mant:52;
57 unsigned int bexp:11;
58 unsigned int sign:1;
59 } parts;
60 u64 bits;
61 double d;
62 } ieee754dp;
63
64 typedef union _ieee754sp {
65 struct ieee754sp_konst parts;
66 float f;
67 u32 bits;
68 } ieee754sp;
69 #endif
70
71 #ifdef __BIG_ENDIAN
72 struct ieee754dp_konst {
73 unsigned sign:1;
74 unsigned bexp:11;
75 unsigned manthi:20;
76 unsigned mantlo:32;
77 };
78
79 typedef union _ieee754dp {
80 struct ieee754dp_konst oparts;
81 struct {
82 unsigned int sign:1;
83 unsigned int bexp:11;
84 u64 mant:52;
85 } parts;
86 double d;
87 u64 bits;
88 } ieee754dp;
89
90 struct ieee754sp_konst {
91 unsigned sign:1;
92 unsigned bexp:8;
93 unsigned mant:23;
94 };
95
96 typedef union _ieee754sp {
97 struct ieee754sp_konst parts;
98 float f;
99 u32 bits;
100 } ieee754sp;
101 #endif
102
103 /*
104 * single precision (often aka float)
105 */
106 int ieee754sp_finite(ieee754sp x);
107 int ieee754sp_class(ieee754sp x);
108
109 ieee754sp ieee754sp_abs(ieee754sp x);
110 ieee754sp ieee754sp_neg(ieee754sp x);
111 ieee754sp ieee754sp_scalb(ieee754sp x, int);
112 ieee754sp ieee754sp_logb(ieee754sp x);
113
114 /* x with sign of y */
115 ieee754sp ieee754sp_copysign(ieee754sp x, ieee754sp y);
116
117 ieee754sp ieee754sp_add(ieee754sp x, ieee754sp y);
118 ieee754sp ieee754sp_sub(ieee754sp x, ieee754sp y);
119 ieee754sp ieee754sp_mul(ieee754sp x, ieee754sp y);
120 ieee754sp ieee754sp_div(ieee754sp x, ieee754sp y);
121
122 ieee754sp ieee754sp_fint(int x);
123 ieee754sp ieee754sp_funs(unsigned x);
124 ieee754sp ieee754sp_flong(s64 x);
125 ieee754sp ieee754sp_fulong(u64 x);
126 ieee754sp ieee754sp_fdp(ieee754dp x);
127
128 int ieee754sp_tint(ieee754sp x);
129 unsigned int ieee754sp_tuns(ieee754sp x);
130 s64 ieee754sp_tlong(ieee754sp x);
131 u64 ieee754sp_tulong(ieee754sp x);
132
133 int ieee754sp_cmp(ieee754sp x, ieee754sp y, int cop, int sig);
134 /*
135 * basic sp math
136 */
137 ieee754sp ieee754sp_modf(ieee754sp x, ieee754sp * ip);
138 ieee754sp ieee754sp_frexp(ieee754sp x, int *exp);
139 ieee754sp ieee754sp_ldexp(ieee754sp x, int exp);
140
141 ieee754sp ieee754sp_ceil(ieee754sp x);
142 ieee754sp ieee754sp_floor(ieee754sp x);
143 ieee754sp ieee754sp_trunc(ieee754sp x);
144
145 ieee754sp ieee754sp_sqrt(ieee754sp x);
146
147 /*
148 * double precision (often aka double)
149 */
150 int ieee754dp_finite(ieee754dp x);
151 int ieee754dp_class(ieee754dp x);
152
153 /* x with sign of y */
154 ieee754dp ieee754dp_copysign(ieee754dp x, ieee754dp y);
155
156 ieee754dp ieee754dp_add(ieee754dp x, ieee754dp y);
157 ieee754dp ieee754dp_sub(ieee754dp x, ieee754dp y);
158 ieee754dp ieee754dp_mul(ieee754dp x, ieee754dp y);
159 ieee754dp ieee754dp_div(ieee754dp x, ieee754dp y);
160
161 ieee754dp ieee754dp_abs(ieee754dp x);
162 ieee754dp ieee754dp_neg(ieee754dp x);
163 ieee754dp ieee754dp_scalb(ieee754dp x, int);
164
165 /* return exponent as integer in floating point format
166 */
167 ieee754dp ieee754dp_logb(ieee754dp x);
168
169 ieee754dp ieee754dp_fint(int x);
170 ieee754dp ieee754dp_funs(unsigned x);
171 ieee754dp ieee754dp_flong(s64 x);
172 ieee754dp ieee754dp_fulong(u64 x);
173 ieee754dp ieee754dp_fsp(ieee754sp x);
174
175 ieee754dp ieee754dp_ceil(ieee754dp x);
176 ieee754dp ieee754dp_floor(ieee754dp x);
177 ieee754dp ieee754dp_trunc(ieee754dp x);
178
179 int ieee754dp_tint(ieee754dp x);
180 unsigned int ieee754dp_tuns(ieee754dp x);
181 s64 ieee754dp_tlong(ieee754dp x);
182 u64 ieee754dp_tulong(ieee754dp x);
183
184 int ieee754dp_cmp(ieee754dp x, ieee754dp y, int cop, int sig);
185 /*
186 * basic sp math
187 */
188 ieee754dp ieee754dp_modf(ieee754dp x, ieee754dp * ip);
189 ieee754dp ieee754dp_frexp(ieee754dp x, int *exp);
190 ieee754dp ieee754dp_ldexp(ieee754dp x, int exp);
191
192 ieee754dp ieee754dp_ceil(ieee754dp x);
193 ieee754dp ieee754dp_floor(ieee754dp x);
194 ieee754dp ieee754dp_trunc(ieee754dp x);
195
196 ieee754dp ieee754dp_sqrt(ieee754dp x);
197
198
199
200 /* 5 types of floating point number
201 */
202 #define IEEE754_CLASS_NORM 0x00
203 #define IEEE754_CLASS_ZERO 0x01
204 #define IEEE754_CLASS_DNORM 0x02
205 #define IEEE754_CLASS_INF 0x03
206 #define IEEE754_CLASS_SNAN 0x04
207 #define IEEE754_CLASS_QNAN 0x05
208
209 /* exception numbers */
210 #define IEEE754_INEXACT 0x01
211 #define IEEE754_UNDERFLOW 0x02
212 #define IEEE754_OVERFLOW 0x04
213 #define IEEE754_ZERO_DIVIDE 0x08
214 #define IEEE754_INVALID_OPERATION 0x10
215
216 /* cmp operators
217 */
218 #define IEEE754_CLT 0x01
219 #define IEEE754_CEQ 0x02
220 #define IEEE754_CGT 0x04
221 #define IEEE754_CUN 0x08
222
223 /* rounding mode
224 */
225 #define IEEE754_RN 0 /* round to nearest */
226 #define IEEE754_RZ 1 /* round toward zero */
227 #define IEEE754_RD 2 /* round toward -Infinity */
228 #define IEEE754_RU 3 /* round toward +Infinity */
229
230 /* other naming */
231 #define IEEE754_RM IEEE754_RD
232 #define IEEE754_RP IEEE754_RU
233
234 /* "normal" comparisons
235 */
ieee754sp_eq(ieee754sp x,ieee754sp y)236 static inline int ieee754sp_eq(ieee754sp x, ieee754sp y)
237 {
238 return ieee754sp_cmp(x, y, IEEE754_CEQ, 0);
239 }
240
ieee754sp_ne(ieee754sp x,ieee754sp y)241 static inline int ieee754sp_ne(ieee754sp x, ieee754sp y)
242 {
243 return ieee754sp_cmp(x, y,
244 IEEE754_CLT | IEEE754_CGT | IEEE754_CUN, 0);
245 }
246
ieee754sp_lt(ieee754sp x,ieee754sp y)247 static inline int ieee754sp_lt(ieee754sp x, ieee754sp y)
248 {
249 return ieee754sp_cmp(x, y, IEEE754_CLT, 0);
250 }
251
ieee754sp_le(ieee754sp x,ieee754sp y)252 static inline int ieee754sp_le(ieee754sp x, ieee754sp y)
253 {
254 return ieee754sp_cmp(x, y, IEEE754_CLT | IEEE754_CEQ, 0);
255 }
256
ieee754sp_gt(ieee754sp x,ieee754sp y)257 static inline int ieee754sp_gt(ieee754sp x, ieee754sp y)
258 {
259 return ieee754sp_cmp(x, y, IEEE754_CGT, 0);
260 }
261
262
ieee754sp_ge(ieee754sp x,ieee754sp y)263 static inline int ieee754sp_ge(ieee754sp x, ieee754sp y)
264 {
265 return ieee754sp_cmp(x, y, IEEE754_CGT | IEEE754_CEQ, 0);
266 }
267
ieee754dp_eq(ieee754dp x,ieee754dp y)268 static inline int ieee754dp_eq(ieee754dp x, ieee754dp y)
269 {
270 return ieee754dp_cmp(x, y, IEEE754_CEQ, 0);
271 }
272
ieee754dp_ne(ieee754dp x,ieee754dp y)273 static inline int ieee754dp_ne(ieee754dp x, ieee754dp y)
274 {
275 return ieee754dp_cmp(x, y,
276 IEEE754_CLT | IEEE754_CGT | IEEE754_CUN, 0);
277 }
278
ieee754dp_lt(ieee754dp x,ieee754dp y)279 static inline int ieee754dp_lt(ieee754dp x, ieee754dp y)
280 {
281 return ieee754dp_cmp(x, y, IEEE754_CLT, 0);
282 }
283
ieee754dp_le(ieee754dp x,ieee754dp y)284 static inline int ieee754dp_le(ieee754dp x, ieee754dp y)
285 {
286 return ieee754dp_cmp(x, y, IEEE754_CLT | IEEE754_CEQ, 0);
287 }
288
ieee754dp_gt(ieee754dp x,ieee754dp y)289 static inline int ieee754dp_gt(ieee754dp x, ieee754dp y)
290 {
291 return ieee754dp_cmp(x, y, IEEE754_CGT, 0);
292 }
293
ieee754dp_ge(ieee754dp x,ieee754dp y)294 static inline int ieee754dp_ge(ieee754dp x, ieee754dp y)
295 {
296 return ieee754dp_cmp(x, y, IEEE754_CGT | IEEE754_CEQ, 0);
297 }
298
299
300 /*
301 * Like strtod
302 */
303 ieee754dp ieee754dp_fstr(const char *s, char **endp);
304 char *ieee754dp_tstr(ieee754dp x, int prec, int fmt, int af);
305
306
307 /*
308 * The control status register
309 */
310 struct _ieee754_csr {
311 #ifdef __BIG_ENDIAN
312 unsigned pad0:7;
313 unsigned nod:1; /* set 1 for no denormalised numbers */
314 unsigned c:1; /* condition */
315 unsigned pad1:5;
316 unsigned cx:6; /* exceptions this operation */
317 unsigned mx:5; /* exception enable mask */
318 unsigned sx:5; /* exceptions total */
319 unsigned rm:2; /* current rounding mode */
320 #endif
321 #ifdef __LITTLE_ENDIAN
322 unsigned rm:2; /* current rounding mode */
323 unsigned sx:5; /* exceptions total */
324 unsigned mx:5; /* exception enable mask */
325 unsigned cx:6; /* exceptions this operation */
326 unsigned pad1:5;
327 unsigned c:1; /* condition */
328 unsigned nod:1; /* set 1 for no denormalised numbers */
329 unsigned pad0:7;
330 #endif
331 };
332 #define ieee754_csr (*(struct _ieee754_csr *)(¤t->thread.fpu.fcr31))
333
ieee754_getrm(void)334 static inline unsigned ieee754_getrm(void)
335 {
336 return (ieee754_csr.rm);
337 }
ieee754_setrm(unsigned rm)338 static inline unsigned ieee754_setrm(unsigned rm)
339 {
340 return (ieee754_csr.rm = rm);
341 }
342
343 /*
344 * get current exceptions
345 */
ieee754_getcx(void)346 static inline unsigned ieee754_getcx(void)
347 {
348 return (ieee754_csr.cx);
349 }
350
351 /* test for current exception condition
352 */
ieee754_cxtest(unsigned n)353 static inline int ieee754_cxtest(unsigned n)
354 {
355 return (ieee754_csr.cx & n);
356 }
357
358 /*
359 * get sticky exceptions
360 */
ieee754_getsx(void)361 static inline unsigned ieee754_getsx(void)
362 {
363 return (ieee754_csr.sx);
364 }
365
366 /* clear sticky conditions
367 */
ieee754_clrsx(void)368 static inline unsigned ieee754_clrsx(void)
369 {
370 return (ieee754_csr.sx = 0);
371 }
372
373 /* test for sticky exception condition
374 */
ieee754_sxtest(unsigned n)375 static inline int ieee754_sxtest(unsigned n)
376 {
377 return (ieee754_csr.sx & n);
378 }
379
380 /* debugging */
381 ieee754sp ieee754sp_dump(char *s, ieee754sp x);
382 ieee754dp ieee754dp_dump(char *s, ieee754dp x);
383
384 #define IEEE754_SPCVAL_PZERO 0
385 #define IEEE754_SPCVAL_NZERO 1
386 #define IEEE754_SPCVAL_PONE 2
387 #define IEEE754_SPCVAL_NONE 3
388 #define IEEE754_SPCVAL_PTEN 4
389 #define IEEE754_SPCVAL_NTEN 5
390 #define IEEE754_SPCVAL_PINFINITY 6
391 #define IEEE754_SPCVAL_NINFINITY 7
392 #define IEEE754_SPCVAL_INDEF 8
393 #define IEEE754_SPCVAL_PMAX 9 /* +max norm */
394 #define IEEE754_SPCVAL_NMAX 10 /* -max norm */
395 #define IEEE754_SPCVAL_PMIN 11 /* +min norm */
396 #define IEEE754_SPCVAL_NMIN 12 /* +min norm */
397 #define IEEE754_SPCVAL_PMIND 13 /* +min denorm */
398 #define IEEE754_SPCVAL_NMIND 14 /* +min denorm */
399 #define IEEE754_SPCVAL_P1E31 15 /* + 1.0e31 */
400 #define IEEE754_SPCVAL_P1E63 16 /* + 1.0e63 */
401
402 extern const struct ieee754dp_konst __ieee754dp_spcvals[];
403 extern const struct ieee754sp_konst __ieee754sp_spcvals[];
404 #define ieee754dp_spcvals ((const ieee754dp *)__ieee754dp_spcvals)
405 #define ieee754sp_spcvals ((const ieee754sp *)__ieee754sp_spcvals)
406
407 /*
408 * Return infinity with given sign
409 */
410 #define ieee754dp_inf(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PINFINITY+(sn)])
411 #define ieee754dp_zero(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PZERO+(sn)])
412 #define ieee754dp_one(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PONE+(sn)])
413 #define ieee754dp_ten(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PTEN+(sn)])
414 #define ieee754dp_indef() (ieee754dp_spcvals[IEEE754_SPCVAL_INDEF])
415 #define ieee754dp_max(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PMAX+(sn)])
416 #define ieee754dp_min(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PMIN+(sn)])
417 #define ieee754dp_mind(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PMIND+(sn)])
418 #define ieee754dp_1e31() (ieee754dp_spcvals[IEEE754_SPCVAL_P1E31])
419 #define ieee754dp_1e63() (ieee754dp_spcvals[IEEE754_SPCVAL_P1E63])
420
421 #define ieee754sp_inf(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PINFINITY+(sn)])
422 #define ieee754sp_zero(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PZERO+(sn)])
423 #define ieee754sp_one(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PONE+(sn)])
424 #define ieee754sp_ten(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PTEN+(sn)])
425 #define ieee754sp_indef() (ieee754sp_spcvals[IEEE754_SPCVAL_INDEF])
426 #define ieee754sp_max(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PMAX+(sn)])
427 #define ieee754sp_min(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PMIN+(sn)])
428 #define ieee754sp_mind(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PMIND+(sn)])
429 #define ieee754sp_1e31() (ieee754sp_spcvals[IEEE754_SPCVAL_P1E31])
430 #define ieee754sp_1e63() (ieee754sp_spcvals[IEEE754_SPCVAL_P1E63])
431
432 /*
433 * Indefinite integer value
434 */
435 #define ieee754si_indef() INT_MAX
436 #ifdef LONG_LONG_MAX
437 #define ieee754di_indef() LONG_LONG_MAX
438 #else
439 #define ieee754di_indef() ((s64)(~0ULL>>1))
440 #endif
441
442 /* IEEE exception context, passed to handler */
443 struct ieee754xctx {
444 const char *op; /* operation name */
445 int rt; /* result type */
446 union {
447 ieee754sp sp; /* single precision */
448 ieee754dp dp; /* double precision */
449 #ifdef IEEE854_XP
450 ieee754xp xp; /* extended precision */
451 #endif
452 int si; /* standard signed integer (32bits) */
453 s64 di; /* extended signed integer (64bits) */
454 } rv; /* default result format implied by op */
455 va_list ap;
456 };
457
458 /* result types for xctx.rt */
459 #define IEEE754_RT_SP 0
460 #define IEEE754_RT_DP 1
461 #define IEEE754_RT_XP 2
462 #define IEEE754_RT_SI 3
463 #define IEEE754_RT_DI 4
464
465 extern void ieee754_xcpt(struct ieee754xctx *xcp);
466
467 /* compat */
468 #define ieee754dp_fix(x) ieee754dp_tint(x)
469 #define ieee754sp_fix(x) ieee754sp_tint(x)
470
471 #endif /* __ARCH_MIPS_MATH_EMU_IEEE754_H */
472