1 /****************************************************************
2  *
3  * The author of this software is David M. Gay.
4  *
5  * Copyright (c) 1991 by AT&T.
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose without fee is hereby granted, provided that this entire notice
9  * is included in all copies of any software which is or includes a copy
10  * or modification of this software and in all copies of the supporting
11  * documentation for such software.
12  *
13  * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
14  * WARRANTY.  IN PARTICULAR, NEITHER THE AUTHOR NOR AT&T MAKES ANY
15  * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
16  * OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
17  *
18  ***************************************************************/
19 
20 /* Please send bug reports to
21 	David M. Gay
22 	AT&T Bell Laboratories, Room 2C-463
23 	600 Mountain Avenue
24 	Murray Hill, NJ 07974-2070
25 	U.S.A.
26 	dmg@research.att.com or research!dmg
27  */
28 
29 #include <machine/ieeefp.h>
30 #include <math.h>
31 #include <float.h>
32 #include <errno.h>
33 #include <assert.h>
34 #include <sys/types.h>
35 #include "../locale/setlocale.h"
36 
37 #ifdef __IEEE_LITTLE_ENDIAN
38 #define IEEE_8087
39 #endif
40 
41 #ifdef __IEEE_BIG_ENDIAN
42 #define IEEE_MC68k
43 #endif
44 
45 #ifdef __Z8000__
46 #define Just_16
47 #endif
48 
49 #ifdef DEBUG
50 #include "stdio.h"
51 #define Bug(x) {fprintf(stderr, "%s\n", x); exit(1);}
52 #endif
53 
54 #ifdef Unsigned_Shifts
55 #define Sign_Extend(a,b) if (b < 0) a |= (__uint32_t)0xffff0000;
56 #else
57 #define Sign_Extend(a,b) /*no-op*/
58 #endif
59 
60 #if defined(IEEE_8087) + defined(IEEE_MC68k) + defined(VAX) + defined(IBM) != 1
61 Exactly one of IEEE_8087, IEEE_MC68k, VAX, or IBM should be defined.
62 #endif
63 
64 /* If we are going to examine or modify specific bits in a double using
65    the word0 and/or word1 macros, then we must wrap the double inside
66    a union.  This is necessary to avoid undefined behavior according to
67    the ANSI C spec.  */
68 union double_union
69 {
70   double d;
71   __uint32_t i[2];
72 };
73 
74 #ifdef IEEE_8087
75 #define word0(x) (x.i[1])
76 #define word1(x) (x.i[0])
77 #else
78 #define word0(x) (x.i[0])
79 #define word1(x) (x.i[1])
80 #endif
81 
82 /* The following is taken from gdtoaimp.h for use with new strtod, but
83    adjusted to avoid invalid type-punning.  */
84 typedef __int32_t Long;
85 
86 /* Unfortunately, because __ULong might be a different type than
87    __uint32_t, we can't re-use union double_union as-is without
88    further edits in strtod.c.  */
89 typedef union { double d; __ULong i[2]; } U;
90 
91 #define dword0(x) word0(x)
92 #define dword1(x) word1(x)
93 #define dval(x) (x.d)
94 
95 #undef SI
96 #ifdef Sudden_Underflow
97 #define SI 1
98 #else
99 #define SI 0
100 #endif
101 
102 #define Storeinc(a,b,c) (*(a)++ = ((b) << 16) | ((c) & 0xffff))
103 
104 /* #define P DBL_MANT_DIG */
105 /* Ten_pmax = floor(P*log(2)/log(5)) */
106 /* Bletch = (highest power of 2 < DBL_MAX_10_EXP) / 16 */
107 /* Quick_max = floor((P-1)*log(FLT_RADIX)/log(10) - 1) */
108 /* Int_max = floor(P*log(FLT_RADIX)/log(10) - 1) */
109 
110 #if defined(IEEE_8087) + defined(IEEE_MC68k)
111 #if defined (_DOUBLE_IS_32BITS)
112 #define Exp_shift   23
113 #define Exp_shift1  23
114 #define Exp_msk1    ((__uint32_t)0x00800000L)
115 #define Exp_msk11   ((__uint32_t)0x00800000L)
116 #define Exp_mask    ((__uint32_t)0x7f800000L)
117 #define P    	    24
118 #define Bias 	    127
119 #define NO_HEX_FP   /* not supported in this case */
120 #define IEEE_Arith
121 #define Emin        (-126)
122 #define Exp_1       ((__uint32_t)0x3f800000L)
123 #define Exp_11      ((__uint32_t)0x3f800000L)
124 #define Ebits 	    8
125 #define Frac_mask   ((__uint32_t)0x007fffffL)
126 #define Frac_mask1  ((__uint32_t)0x007fffffL)
127 #define Ten_pmax    10
128 #define Sign_bit    ((__uint32_t)0x80000000L)
129 #define Ten_pmax    10
130 #define Bletch	    2
131 #define Bndry_mask  ((__uint32_t)0x007fffffL)
132 #define Bndry_mask1 ((__uint32_t)0x007fffffL)
133 #define LSB 1
134 #define Sign_bit    ((__uint32_t)0x80000000L)
135 #define Log2P 	    1
136 #define Tiny0 	    0
137 #define Tiny1 	    1
138 #define Quick_max   5
139 #define Int_max     6
140 #define Infinite(x) (word0(x) == ((__uint32_t)0x7f800000L))
141 #undef word0
142 #undef word1
143 #undef dword0
144 #undef dword1
145 
146 #define word0(x) (x.i[0])
147 #define word1(x) 0
148 #define dword0(x) word0(x)
149 #define dword1(x) 0
150 #else
151 
152 #define Exp_shift  20
153 #define Exp_shift1 20
154 #define Exp_msk1    ((__uint32_t)0x100000L)
155 #define Exp_msk11   ((__uint32_t)0x100000L)
156 #define Exp_mask  ((__uint32_t)0x7ff00000L)
157 #define P 53
158 #define Bias 1023
159 #define IEEE_Arith
160 #define Emin (-1022)
161 #define Exp_1  ((__uint32_t)0x3ff00000L)
162 #define Exp_11 ((__uint32_t)0x3ff00000L)
163 #define Ebits 11
164 #define Frac_mask  ((__uint32_t)0xfffffL)
165 #define Frac_mask1 ((__uint32_t)0xfffffL)
166 #define Ten_pmax 22
167 #define Bletch 0x10
168 #define Bndry_mask  ((__uint32_t)0xfffffL)
169 #define Bndry_mask1 ((__uint32_t)0xfffffL)
170 #define LSB 1
171 #define Sign_bit ((__uint32_t)0x80000000L)
172 #define Log2P 1
173 #define Tiny0 0
174 #define Tiny1 1
175 #define Quick_max 14
176 #define Int_max 14
177 #define Infinite(x) (word0(x) == ((__uint32_t)0x7ff00000L)) /* sufficient test for here */
178 
179 #endif /* !_DOUBLE_IS_32BITS */
180 
181 #ifndef Flt_Rounds
182 #ifdef FLT_ROUNDS
183 #define Flt_Rounds FLT_ROUNDS
184 #else
185 #define Flt_Rounds 1
186 #endif
187 #endif /*Flt_Rounds*/
188 
189 #else /* !IEEE_8087 && !IEEE_MC68k */
190 #undef  Sudden_Underflow
191 #define Sudden_Underflow
192 #ifdef IBM
193 #define Flt_Rounds 0
194 #define Exp_shift  24
195 #define Exp_shift1 24
196 #define Exp_msk1   ((__uint32_t)0x1000000L)
197 #define Exp_msk11  ((__uint32_t)0x1000000L)
198 #define Exp_mask  ((__uint32_t)0x7f000000L)
199 #define P 14
200 #define Bias 65
201 #define Exp_1  ((__uint32_t)0x41000000L)
202 #define Exp_11 ((__uint32_t)0x41000000L)
203 #define Ebits 8	/* exponent has 7 bits, but 8 is the right value in b2d */
204 #define Frac_mask  ((__uint32_t)0xffffffL)
205 #define Frac_mask1 ((__uint32_t)0xffffffL)
206 #define Bletch 4
207 #define Ten_pmax 22
208 #define Bndry_mask  ((__uint32_t)0xefffffL)
209 #define Bndry_mask1 ((__uint32_t)0xffffffL)
210 #define LSB 1
211 #define Sign_bit ((__uint32_t)0x80000000L)
212 #define Log2P 4
213 #define Tiny0 ((__uint32_t)0x100000L)
214 #define Tiny1 0
215 #define Quick_max 14
216 #define Int_max 15
217 #else /* VAX */
218 #define Flt_Rounds 1
219 #define Exp_shift  23
220 #define Exp_shift1 7
221 #define Exp_msk1    0x80
222 #define Exp_msk11   ((__uint32_t)0x800000L)
223 #define Exp_mask  ((__uint32_t)0x7f80L)
224 #define P 56
225 #define Bias 129
226 #define Exp_1  ((__uint32_t)0x40800000L)
227 #define Exp_11 ((__uint32_t)0x4080L)
228 #define Ebits 8
229 #define Frac_mask  ((__uint32_t)0x7fffffL)
230 #define Frac_mask1 ((__uint32_t)0xffff007fL)
231 #define Ten_pmax 24
232 #define Bletch 2
233 #define Bndry_mask  ((__uint32_t)0xffff007fL)
234 #define Bndry_mask1 ((__uint32_t)0xffff007fL)
235 #define LSB ((__uint32_t)0x10000L)
236 #define Sign_bit ((__uint32_t)0x8000L)
237 #define Log2P 1
238 #define Tiny0 0x80
239 #define Tiny1 0
240 #define Quick_max 15
241 #define Int_max 15
242 #endif
243 #endif
244 
245 #ifndef IEEE_Arith
246 #define ROUND_BIASED
247 #else
248 #define Scale_Bit 0x10
249 #if defined(_DOUBLE_IS_32BITS) && defined(__v800)
250 #define n_bigtens 2
251 #else
252 #define n_bigtens 5
253 #endif
254 #endif
255 
256 #ifdef IBM
257 #define n_bigtens 3
258 #endif
259 
260 #ifdef VAX
261 #define n_bigtens 2
262 #endif
263 
264 #ifndef __NO_INFNAN_CHECK
265 #define INFNAN_CHECK
266 #endif
267 
268 #ifdef RND_PRODQUOT
269 #define rounded_product(a,b) a = rnd_prod(a, b)
270 #define rounded_quotient(a,b) a = rnd_quot(a, b)
271 #ifdef KR_headers
272 extern double rnd_prod(), rnd_quot();
273 #else
274 extern double rnd_prod(double, double), rnd_quot(double, double);
275 #endif
276 #else
277 #define rounded_product(a,b) a *= b
278 #define rounded_quotient(a,b) a /= b
279 #endif
280 
281 #define Big0 (Frac_mask1 | Exp_msk1*(DBL_MAX_EXP+Bias-1))
282 #define Big1 ((__uint32_t)0xffffffffL)
283 
284 #ifndef Just_16
285 /* When Pack_32 is not defined, we store 16 bits per 32-bit long.
286  * This makes some inner loops simpler and sometimes saves work
287  * during multiplications, but it often seems to make things slightly
288  * slower.  Hence the default is now to store 32 bits per long.
289  */
290 
291  #ifndef Pack_32
292   #define Pack_32
293  #endif
294 #else  /* Just_16 */
295  #ifndef Pack_16
296   #define Pack_16
297  #endif
298 #endif /* Just_16 */
299 
300 #ifdef Pack_32
301 #define ULbits 32
302 #define kshift 5
303 #define kmask 31
304 #define ALL_ON 0xffffffff
305 #else
306 #define ULbits 16
307 #define kshift 4
308 #define kmask 15
309 #define ALL_ON 0xffff
310 #endif
311 
312 #ifdef __cplusplus
313 extern "C" double strtod(const char *s00, char **se);
314 extern "C" char *dtoa(double d, int mode, int ndigits,
315 			int *decpt, int *sign, char **rve);
316 #endif
317 
318 
319 typedef struct _Bigint _Bigint;
320 
321 #define Balloc	_Balloc
322 #define Bfree	_Bfree
323 #define multadd __multadd
324 #define s2b	__s2b
325 #define lo0bits __lo0bits
326 #define hi0bits __hi0bits
327 #define i2b	__i2b
328 #define mult	__multiply
329 #define pow5mult	__pow5mult
330 #define lshift	__lshift
331 #define match   __match
332 #define cmp	__mcmp
333 #define diff	__mdiff
334 #define ulp 	__ulp
335 #define b2d	__b2d
336 #define d2b	__d2b
337 #define ratio	__ratio
338 #define any_on	__any_on
339 #define gethex  __gethex
340 #define copybits 	__copybits
341 #define hexnan	__hexnan
342 
343 #if !defined(PREFER_SIZE_OVER_SPEED) && !defined(__OPTIMIZE_SIZE__) && !defined(_SMALL_HEXDIG)
344 #define __get_hexdig(x) __hexdig[x] /* NOTE: must evaluate arg only once */
345 #else /* !defined(PREFER_SIZE_OVER_SPEED) && !defined(__OPTIMIZE_SIZE__) && !defined(_SMALL_HEXDIG) */
346 #define __get_hexdig(x) __hexdig_fun(x)
347 #endif /* !defined(PREFER_SIZE_OVER_SPEED) && !defined(__OPTIMIZE_SIZE__) && !defined(_SMALL_HEXDIG) */
348 
349 #define tens __mprec_tens
350 #define bigtens __mprec_bigtens
351 #define tinytens __mprec_tinytens
352 
353 char *__alloc_dtoa_result(int len);
354 
355 int __mprec_register_exit(void);
356 
357 struct _Bigint
358 {
359   int _k, _maxwds, _sign, _wds;
360   uint32_t _x[];
361 };
362 
363 struct FPI;
364 double 		ulp (double x);
365 double		b2d (_Bigint *a , int *e);
366 _Bigint *	Balloc (int k);
367 void 		Bfree (_Bigint *v);
368 _Bigint *	multadd (_Bigint *, int, int);
369 _Bigint *	s2b (const char*, int, int, __ULong);
370 _Bigint	*	i2b (int);
371 _Bigint *	mult (_Bigint *, _Bigint *);
372 _Bigint *	pow5mult (_Bigint *, int k);
373 int 		hi0bits (__ULong);
374 int 		lo0bits (__ULong *);
375 _Bigint *	d2b (double d, int *e, int *bits);
376 _Bigint *	lshift (_Bigint *b, int k);
377 int		match (const char**, char*);
378 _Bigint *	diff (_Bigint *a, _Bigint *b);
379 int		cmp (_Bigint *a, _Bigint *b);
380 int		gethex (const char **sp, const struct FPI *fpi, Long *exp, _Bigint **bp, int sign, locale_t loc);
381 double		ratio (_Bigint *a, _Bigint *b);
382 __ULong		any_on (_Bigint *b, int k);
383 void		copybits (__ULong *c, int n, _Bigint *b);
384 double		_strtod_l (const char *__restrict s00,
385 			   char **__restrict se, locale_t loc);
386 #if defined (_HAVE_LONG_DOUBLE) && !defined (_LDBL_EQ_DBL) || 1
387 int		_strtorx_l (const char *, char **, int,
388 			    void *, locale_t);
389 int		_strtodg_l (const char *s00, char **se,
390 			    struct FPI *fpi, Long *exp, __ULong *bits,
391 			    locale_t);
392 #endif /* _HAVE_LONG_DOUBLE && !_LDBL_EQ_DBL */
393 
394 #if defined(PREFER_SIZE_OVER_SPEED) || defined(__OPTIMIZE_SIZE__) || defined(_SMALL_HEXDIG)
395 unsigned char __hexdig_fun (unsigned char);
396 #endif /* !defined(PREFER_SIZE_OVER_SPEED) && !defined(__OPTIMIZE_SIZE__) && !defined(_SMALL_HEXDIG) */
397 #ifdef INFNAN_CHECK
398 int		hexnan (const char **sp, const struct FPI *fpi, __ULong *x0);
399 #endif
400 
401 #define Bcopy(x,y) memcpy((char *)&x->_sign, (char *)&y->_sign, y->_wds*sizeof(__Long) + 2*sizeof(int))
402 
403 extern const double tinytens[];
404 extern const double bigtens[];
405 extern const double tens[];
406 #if !defined(PREFER_SIZE_OVER_SPEED) && !defined(__OPTIMIZE_SIZE__) && !defined(_SMALL_HEXDIG)
407 extern const unsigned char __hexdig[];
408 #endif /* !defined(PREFER_SIZE_OVER_SPEED) && !defined(__OPTIMIZE_SIZE__) && !defined(_SMALL_HEXDIG) */
409 
410 
411 double _mprec_log10 (int);
412