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f5bc1778 DJ |
1 | /* Decimal 64-bit format module for the decNumber C Library. |
2 | Copyright (C) 2005, 2007 Free Software Foundation, Inc. | |
3 | Contributed by IBM Corporation. Author Mike Cowlishaw. | |
4 | ||
5 | This file is part of GCC. | |
6 | ||
7 | GCC is free software; you can redistribute it and/or modify it under | |
8 | the terms of the GNU General Public License as published by the Free | |
9 | Software Foundation; either version 2, or (at your option) any later | |
10 | version. | |
11 | ||
12 | In addition to the permissions in the GNU General Public License, | |
13 | the Free Software Foundation gives you unlimited permission to link | |
14 | the compiled version of this file into combinations with other | |
15 | programs, and to distribute those combinations without any | |
16 | restriction coming from the use of this file. (The General Public | |
17 | License restrictions do apply in other respects; for example, they | |
18 | cover modification of the file, and distribution when not linked | |
19 | into a combine executable.) | |
20 | ||
21 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
22 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
23 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
24 | for more details. | |
25 | ||
26 | You should have received a copy of the GNU General Public License | |
27 | along with GCC; see the file COPYING. If not, write to the Free | |
28 | Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA | |
29 | 02110-1301, USA. */ | |
30 | ||
31 | /* ------------------------------------------------------------------ */ | |
87d32bb7 | 32 | /* Decimal 64-bit format module */ |
f5bc1778 DJ |
33 | /* ------------------------------------------------------------------ */ |
34 | /* This module comprises the routines for decimal64 format numbers. */ | |
35 | /* Conversions are supplied to and from decNumber and String. */ | |
36 | /* */ | |
37 | /* This is used when decNumber provides operations, either for all */ | |
38 | /* operations or as a proxy between decNumber and decSingle. */ | |
39 | /* */ | |
40 | /* Error handling is the same as decNumber (qv.). */ | |
41 | /* ------------------------------------------------------------------ */ | |
42 | #include <string.h> /* [for memset/memcpy] */ | |
43 | #include <stdio.h> /* [for printf] */ | |
44 | ||
87d32bb7 DD |
45 | #include "dconfig.h" /* GCC definitions */ |
46 | #define DECNUMDIGITS 16 /* make decNumbers with space for 16 */ | |
f5bc1778 DJ |
47 | #include "decNumber.h" /* base number library */ |
48 | #include "decNumberLocal.h" /* decNumber local types, etc. */ | |
49 | #include "decimal64.h" /* our primary include */ | |
50 | ||
51 | /* Utility routines and tables [in decimal64.c]; externs for C++ */ | |
f5bc1778 DJ |
52 | extern const uInt COMBEXP[32], COMBMSD[32]; |
53 | extern const uShort DPD2BIN[1024]; | |
54 | extern const uShort BIN2DPD[1000]; | |
55 | extern const uByte BIN2CHAR[4001]; | |
56 | ||
57 | extern void decDigitsFromDPD(decNumber *, const uInt *, Int); | |
58 | extern void decDigitsToDPD(const decNumber *, uInt *, Int); | |
59 | ||
60 | #if DECTRACE || DECCHECK | |
61 | void decimal64Show(const decimal64 *); /* for debug */ | |
62 | extern void decNumberShow(const decNumber *); /* .. */ | |
63 | #endif | |
64 | ||
65 | /* Useful macro */ | |
66 | /* Clear a structure (e.g., a decNumber) */ | |
67 | #define DEC_clear(d) memset(d, 0, sizeof(*d)) | |
68 | ||
69 | /* define and include the tables to use for conversions */ | |
70 | #define DEC_BIN2CHAR 1 | |
71 | #define DEC_DPD2BIN 1 | |
72 | #define DEC_BIN2DPD 1 /* used for all sizes */ | |
73 | #include "decDPD.h" /* lookup tables */ | |
74 | ||
75 | /* ------------------------------------------------------------------ */ | |
76 | /* decimal64FromNumber -- convert decNumber to decimal64 */ | |
77 | /* */ | |
87d32bb7 | 78 | /* ds is the target decimal64 */ |
f5bc1778 | 79 | /* dn is the source number (assumed valid) */ |
87d32bb7 | 80 | /* set is the context, used only for reporting errors */ |
f5bc1778 DJ |
81 | /* */ |
82 | /* The set argument is used only for status reporting and for the */ | |
83 | /* rounding mode (used if the coefficient is more than DECIMAL64_Pmax */ | |
84 | /* digits or an overflow is detected). If the exponent is out of the */ | |
85 | /* valid range then Overflow or Underflow will be raised. */ | |
86 | /* After Underflow a subnormal result is possible. */ | |
87 | /* */ | |
88 | /* DEC_Clamped is set if the number has to be 'folded down' to fit, */ | |
89 | /* by reducing its exponent and multiplying the coefficient by a */ | |
90 | /* power of ten, or if the exponent on a zero had to be clamped. */ | |
91 | /* ------------------------------------------------------------------ */ | |
92 | decimal64 * decimal64FromNumber(decimal64 *d64, const decNumber *dn, | |
93 | decContext *set) { | |
94 | uInt status=0; /* status accumulator */ | |
95 | Int ae; /* adjusted exponent */ | |
96 | decNumber dw; /* work */ | |
97 | decContext dc; /* .. */ | |
f5bc1778 | 98 | uInt comb, exp; /* .. */ |
87d32bb7 | 99 | uInt uiwork; /* for macros */ |
f5bc1778 DJ |
100 | uInt targar[2]={0, 0}; /* target 64-bit */ |
101 | #define targhi targar[1] /* name the word with the sign */ | |
102 | #define targlo targar[0] /* and the other */ | |
103 | ||
104 | /* If the number has too many digits, or the exponent could be */ | |
105 | /* out of range then reduce the number under the appropriate */ | |
106 | /* constraints. This could push the number to Infinity or zero, */ | |
107 | /* so this check and rounding must be done before generating the */ | |
108 | /* decimal64] */ | |
87d32bb7 DD |
109 | ae=dn->exponent+dn->digits-1; /* [0 if special] */ |
110 | if (dn->digits>DECIMAL64_Pmax /* too many digits */ | |
111 | || ae>DECIMAL64_Emax /* likely overflow */ | |
f5bc1778 DJ |
112 | || ae<DECIMAL64_Emin) { /* likely underflow */ |
113 | decContextDefault(&dc, DEC_INIT_DECIMAL64); /* [no traps] */ | |
114 | dc.round=set->round; /* use supplied rounding */ | |
115 | decNumberPlus(&dw, dn, &dc); /* (round and check) */ | |
116 | /* [this changes -0 to 0, so enforce the sign...] */ | |
117 | dw.bits|=dn->bits&DECNEG; | |
118 | status=dc.status; /* save status */ | |
119 | dn=&dw; /* use the work number */ | |
120 | } /* maybe out of range */ | |
121 | ||
122 | if (dn->bits&DECSPECIAL) { /* a special value */ | |
123 | if (dn->bits&DECINF) targhi=DECIMAL_Inf<<24; | |
124 | else { /* sNaN or qNaN */ | |
87d32bb7 | 125 | if ((*dn->lsu!=0 || dn->digits>1) /* non-zero coefficient */ |
f5bc1778 DJ |
126 | && (dn->digits<DECIMAL64_Pmax)) { /* coefficient fits */ |
127 | decDigitsToDPD(dn, targar, 0); | |
128 | } | |
129 | if (dn->bits&DECNAN) targhi|=DECIMAL_NaN<<24; | |
130 | else targhi|=DECIMAL_sNaN<<24; | |
131 | } /* a NaN */ | |
132 | } /* special */ | |
133 | ||
134 | else { /* is finite */ | |
135 | if (decNumberIsZero(dn)) { /* is a zero */ | |
136 | /* set and clamp exponent */ | |
137 | if (dn->exponent<-DECIMAL64_Bias) { | |
138 | exp=0; /* low clamp */ | |
139 | status|=DEC_Clamped; | |
140 | } | |
141 | else { | |
142 | exp=dn->exponent+DECIMAL64_Bias; /* bias exponent */ | |
143 | if (exp>DECIMAL64_Ehigh) { /* top clamp */ | |
144 | exp=DECIMAL64_Ehigh; | |
145 | status|=DEC_Clamped; | |
146 | } | |
147 | } | |
148 | comb=(exp>>5) & 0x18; /* msd=0, exp top 2 bits .. */ | |
149 | } | |
150 | else { /* non-zero finite number */ | |
87d32bb7 | 151 | uInt msd; /* work */ |
f5bc1778 DJ |
152 | Int pad=0; /* coefficient pad digits */ |
153 | ||
154 | /* the dn is known to fit, but it may need to be padded */ | |
155 | exp=(uInt)(dn->exponent+DECIMAL64_Bias); /* bias exponent */ | |
156 | if (exp>DECIMAL64_Ehigh) { /* fold-down case */ | |
157 | pad=exp-DECIMAL64_Ehigh; | |
158 | exp=DECIMAL64_Ehigh; /* [to maximum] */ | |
159 | status|=DEC_Clamped; | |
160 | } | |
161 | ||
162 | /* fastpath common case */ | |
163 | if (DECDPUN==3 && pad==0) { | |
164 | uInt dpd[6]={0,0,0,0,0,0}; | |
165 | uInt i; | |
166 | Int d=dn->digits; | |
167 | for (i=0; d>0; i++, d-=3) dpd[i]=BIN2DPD[dn->lsu[i]]; | |
168 | targlo =dpd[0]; | |
169 | targlo|=dpd[1]<<10; | |
170 | targlo|=dpd[2]<<20; | |
171 | if (dn->digits>6) { | |
172 | targlo|=dpd[3]<<30; | |
173 | targhi =dpd[3]>>2; | |
174 | targhi|=dpd[4]<<8; | |
175 | } | |
176 | msd=dpd[5]; /* [did not really need conversion] */ | |
177 | } | |
178 | else { /* general case */ | |
179 | decDigitsToDPD(dn, targar, pad); | |
180 | /* save and clear the top digit */ | |
181 | msd=targhi>>18; | |
182 | targhi&=0x0003ffff; | |
183 | } | |
184 | ||
185 | /* create the combination field */ | |
186 | if (msd>=8) comb=0x18 | ((exp>>7) & 0x06) | (msd & 0x01); | |
187 | else comb=((exp>>5) & 0x18) | msd; | |
188 | } | |
189 | targhi|=comb<<26; /* add combination field .. */ | |
190 | targhi|=(exp&0xff)<<18; /* .. and exponent continuation */ | |
191 | } /* finite */ | |
192 | ||
193 | if (dn->bits&DECNEG) targhi|=0x80000000; /* add sign bit */ | |
194 | ||
195 | /* now write to storage; this is now always endian */ | |
f5bc1778 | 196 | if (DECLITEND) { |
87d32bb7 DD |
197 | /* lo int then hi */ |
198 | UBFROMUI(d64->bytes, targar[0]); | |
199 | UBFROMUI(d64->bytes+4, targar[1]); | |
f5bc1778 DJ |
200 | } |
201 | else { | |
87d32bb7 DD |
202 | /* hi int then lo */ |
203 | UBFROMUI(d64->bytes, targar[1]); | |
204 | UBFROMUI(d64->bytes+4, targar[0]); | |
f5bc1778 DJ |
205 | } |
206 | ||
207 | if (status!=0) decContextSetStatus(set, status); /* pass on status */ | |
208 | /* decimal64Show(d64); */ | |
209 | return d64; | |
210 | } /* decimal64FromNumber */ | |
211 | ||
212 | /* ------------------------------------------------------------------ */ | |
213 | /* decimal64ToNumber -- convert decimal64 to decNumber */ | |
214 | /* d64 is the source decimal64 */ | |
215 | /* dn is the target number, with appropriate space */ | |
216 | /* No error is possible. */ | |
217 | /* ------------------------------------------------------------------ */ | |
218 | decNumber * decimal64ToNumber(const decimal64 *d64, decNumber *dn) { | |
219 | uInt msd; /* coefficient MSD */ | |
220 | uInt exp; /* exponent top two bits */ | |
221 | uInt comb; /* combination field */ | |
87d32bb7 DD |
222 | Int need; /* work */ |
223 | uInt uiwork; /* for macros */ | |
f5bc1778 DJ |
224 | uInt sourar[2]; /* source 64-bit */ |
225 | #define sourhi sourar[1] /* name the word with the sign */ | |
226 | #define sourlo sourar[0] /* and the lower word */ | |
227 | ||
228 | /* load source from storage; this is endian */ | |
f5bc1778 | 229 | if (DECLITEND) { |
87d32bb7 DD |
230 | sourlo=UBTOUI(d64->bytes ); /* directly load the low int */ |
231 | sourhi=UBTOUI(d64->bytes+4); /* then the high int */ | |
f5bc1778 DJ |
232 | } |
233 | else { | |
87d32bb7 DD |
234 | sourhi=UBTOUI(d64->bytes ); /* directly load the high int */ |
235 | sourlo=UBTOUI(d64->bytes+4); /* then the low int */ | |
f5bc1778 DJ |
236 | } |
237 | ||
238 | comb=(sourhi>>26)&0x1f; /* combination field */ | |
239 | ||
240 | decNumberZero(dn); /* clean number */ | |
241 | if (sourhi&0x80000000) dn->bits=DECNEG; /* set sign if negative */ | |
242 | ||
243 | msd=COMBMSD[comb]; /* decode the combination field */ | |
244 | exp=COMBEXP[comb]; /* .. */ | |
245 | ||
87d32bb7 | 246 | if (exp==3) { /* is a special */ |
f5bc1778 DJ |
247 | if (msd==0) { |
248 | dn->bits|=DECINF; | |
249 | return dn; /* no coefficient needed */ | |
250 | } | |
251 | else if (sourhi&0x02000000) dn->bits|=DECSNAN; | |
252 | else dn->bits|=DECNAN; | |
253 | msd=0; /* no top digit */ | |
254 | } | |
255 | else { /* is a finite number */ | |
256 | dn->exponent=(exp<<8)+((sourhi>>18)&0xff)-DECIMAL64_Bias; /* unbiased */ | |
257 | } | |
258 | ||
259 | /* get the coefficient */ | |
260 | sourhi&=0x0003ffff; /* clean coefficient continuation */ | |
261 | if (msd) { /* non-zero msd */ | |
262 | sourhi|=msd<<18; /* prefix to coefficient */ | |
263 | need=6; /* process 6 declets */ | |
264 | } | |
265 | else { /* msd=0 */ | |
266 | if (!sourhi) { /* top word 0 */ | |
267 | if (!sourlo) return dn; /* easy: coefficient is 0 */ | |
268 | need=3; /* process at least 3 declets */ | |
269 | if (sourlo&0xc0000000) need++; /* process 4 declets */ | |
270 | /* [could reduce some more, here] */ | |
271 | } | |
272 | else { /* some bits in top word, msd=0 */ | |
273 | need=4; /* process at least 4 declets */ | |
274 | if (sourhi&0x0003ff00) need++; /* top declet!=0, process 5 */ | |
275 | } | |
276 | } /*msd=0 */ | |
277 | ||
278 | decDigitsFromDPD(dn, sourar, need); /* process declets */ | |
279 | return dn; | |
280 | } /* decimal64ToNumber */ | |
281 | ||
282 | ||
283 | /* ------------------------------------------------------------------ */ | |
87d32bb7 | 284 | /* to-scientific-string -- conversion to numeric string */ |
f5bc1778 DJ |
285 | /* to-engineering-string -- conversion to numeric string */ |
286 | /* */ | |
287 | /* decimal64ToString(d64, string); */ | |
87d32bb7 | 288 | /* decimal64ToEngString(d64, string); */ |
f5bc1778 DJ |
289 | /* */ |
290 | /* d64 is the decimal64 format number to convert */ | |
291 | /* string is the string where the result will be laid out */ | |
292 | /* */ | |
293 | /* string must be at least 24 characters */ | |
294 | /* */ | |
295 | /* No error is possible, and no status can be set. */ | |
296 | /* ------------------------------------------------------------------ */ | |
297 | char * decimal64ToEngString(const decimal64 *d64, char *string){ | |
87d32bb7 | 298 | decNumber dn; /* work */ |
f5bc1778 DJ |
299 | decimal64ToNumber(d64, &dn); |
300 | decNumberToEngString(&dn, string); | |
301 | return string; | |
302 | } /* decimal64ToEngString */ | |
303 | ||
304 | char * decimal64ToString(const decimal64 *d64, char *string){ | |
305 | uInt msd; /* coefficient MSD */ | |
306 | Int exp; /* exponent top two bits or full */ | |
307 | uInt comb; /* combination field */ | |
87d32bb7 | 308 | char *cstart; /* coefficient start */ |
f5bc1778 | 309 | char *c; /* output pointer in string */ |
87d32bb7 | 310 | const uByte *u; /* work */ |
f5bc1778 DJ |
311 | char *s, *t; /* .. (source, target) */ |
312 | Int dpd; /* .. */ | |
313 | Int pre, e; /* .. */ | |
87d32bb7 | 314 | uInt uiwork; /* for macros */ |
f5bc1778 DJ |
315 | |
316 | uInt sourar[2]; /* source 64-bit */ | |
317 | #define sourhi sourar[1] /* name the word with the sign */ | |
318 | #define sourlo sourar[0] /* and the lower word */ | |
319 | ||
320 | /* load source from storage; this is endian */ | |
f5bc1778 | 321 | if (DECLITEND) { |
87d32bb7 DD |
322 | sourlo=UBTOUI(d64->bytes ); /* directly load the low int */ |
323 | sourhi=UBTOUI(d64->bytes+4); /* then the high int */ | |
f5bc1778 DJ |
324 | } |
325 | else { | |
87d32bb7 DD |
326 | sourhi=UBTOUI(d64->bytes ); /* directly load the high int */ |
327 | sourlo=UBTOUI(d64->bytes+4); /* then the low int */ | |
f5bc1778 DJ |
328 | } |
329 | ||
330 | c=string; /* where result will go */ | |
331 | if (((Int)sourhi)<0) *c++='-'; /* handle sign */ | |
332 | ||
333 | comb=(sourhi>>26)&0x1f; /* combination field */ | |
334 | msd=COMBMSD[comb]; /* decode the combination field */ | |
335 | exp=COMBEXP[comb]; /* .. */ | |
336 | ||
337 | if (exp==3) { | |
338 | if (msd==0) { /* infinity */ | |
87d32bb7 | 339 | strcpy(c, "Inf"); |
f5bc1778 DJ |
340 | strcpy(c+3, "inity"); |
341 | return string; /* easy */ | |
342 | } | |
343 | if (sourhi&0x02000000) *c++='s'; /* sNaN */ | |
344 | strcpy(c, "NaN"); /* complete word */ | |
345 | c+=3; /* step past */ | |
346 | if (sourlo==0 && (sourhi&0x0003ffff)==0) return string; /* zero payload */ | |
347 | /* otherwise drop through to add integer; set correct exp */ | |
348 | exp=0; msd=0; /* setup for following code */ | |
349 | } | |
350 | else exp=(exp<<8)+((sourhi>>18)&0xff)-DECIMAL64_Bias; | |
351 | ||
352 | /* convert 16 digits of significand to characters */ | |
353 | cstart=c; /* save start of coefficient */ | |
354 | if (msd) *c++='0'+(char)msd; /* non-zero most significant digit */ | |
355 | ||
356 | /* Now decode the declets. After extracting each one, it is */ | |
357 | /* decoded to binary and then to a 4-char sequence by table lookup; */ | |
358 | /* the 4-chars are a 1-char length (significant digits, except 000 */ | |
359 | /* has length 0). This allows us to left-align the first declet */ | |
360 | /* with non-zero content, then remaining ones are full 3-char */ | |
361 | /* length. We use fixed-length memcpys because variable-length */ | |
362 | /* causes a subroutine call in GCC. (These are length 4 for speed */ | |
363 | /* and are safe because the array has an extra terminator byte.) */ | |
87d32bb7 | 364 | #define dpd2char u=&BIN2CHAR[DPD2BIN[dpd]*4]; \ |
f5bc1778 DJ |
365 | if (c!=cstart) {memcpy(c, u+1, 4); c+=3;} \ |
366 | else if (*u) {memcpy(c, u+4-*u, 4); c+=*u;} | |
367 | ||
368 | dpd=(sourhi>>8)&0x3ff; /* declet 1 */ | |
369 | dpd2char; | |
370 | dpd=((sourhi&0xff)<<2) | (sourlo>>30); /* declet 2 */ | |
371 | dpd2char; | |
372 | dpd=(sourlo>>20)&0x3ff; /* declet 3 */ | |
373 | dpd2char; | |
374 | dpd=(sourlo>>10)&0x3ff; /* declet 4 */ | |
375 | dpd2char; | |
376 | dpd=(sourlo)&0x3ff; /* declet 5 */ | |
377 | dpd2char; | |
378 | ||
379 | if (c==cstart) *c++='0'; /* all zeros -- make 0 */ | |
380 | ||
87d32bb7 | 381 | if (exp==0) { /* integer or NaN case -- easy */ |
f5bc1778 DJ |
382 | *c='\0'; /* terminate */ |
383 | return string; | |
384 | } | |
385 | ||
386 | /* non-0 exponent */ | |
387 | e=0; /* assume no E */ | |
388 | pre=c-cstart+exp; | |
389 | /* [here, pre-exp is the digits count (==1 for zero)] */ | |
390 | if (exp>0 || pre<-5) { /* need exponential form */ | |
391 | e=pre-1; /* calculate E value */ | |
392 | pre=1; /* assume one digit before '.' */ | |
393 | } /* exponential form */ | |
394 | ||
395 | /* modify the coefficient, adding 0s, '.', and E+nn as needed */ | |
396 | s=c-1; /* source (LSD) */ | |
397 | if (pre>0) { /* ddd.ddd (plain), perhaps with E */ | |
398 | char *dotat=cstart+pre; | |
399 | if (dotat<c) { /* if embedded dot needed... */ | |
400 | t=c; /* target */ | |
401 | for (; s>=dotat; s--, t--) *t=*s; /* open the gap; leave t at gap */ | |
402 | *t='.'; /* insert the dot */ | |
403 | c++; /* length increased by one */ | |
404 | } | |
405 | ||
406 | /* finally add the E-part, if needed; it will never be 0, and has */ | |
407 | /* a maximum length of 3 digits */ | |
408 | if (e!=0) { | |
87d32bb7 DD |
409 | *c++='E'; /* starts with E */ |
410 | *c++='+'; /* assume positive */ | |
f5bc1778 DJ |
411 | if (e<0) { |
412 | *(c-1)='-'; /* oops, need '-' */ | |
413 | e=-e; /* uInt, please */ | |
414 | } | |
87d32bb7 | 415 | u=&BIN2CHAR[e*4]; /* -> length byte */ |
f5bc1778 DJ |
416 | memcpy(c, u+4-*u, 4); /* copy fixed 4 characters [is safe] */ |
417 | c+=*u; /* bump pointer appropriately */ | |
418 | } | |
419 | *c='\0'; /* add terminator */ | |
420 | /*printf("res %s\n", string); */ | |
421 | return string; | |
422 | } /* pre>0 */ | |
423 | ||
424 | /* -5<=pre<=0: here for plain 0.ddd or 0.000ddd forms (can never have E) */ | |
425 | t=c+1-pre; | |
426 | *(t+1)='\0'; /* can add terminator now */ | |
427 | for (; s>=cstart; s--, t--) *t=*s; /* shift whole coefficient right */ | |
428 | c=cstart; | |
429 | *c++='0'; /* always starts with 0. */ | |
430 | *c++='.'; | |
431 | for (; pre<0; pre++) *c++='0'; /* add any 0's after '.' */ | |
432 | /*printf("res %s\n", string); */ | |
433 | return string; | |
434 | } /* decimal64ToString */ | |
435 | ||
436 | /* ------------------------------------------------------------------ */ | |
437 | /* to-number -- conversion from numeric string */ | |
438 | /* */ | |
439 | /* decimal64FromString(result, string, set); */ | |
440 | /* */ | |
441 | /* result is the decimal64 format number which gets the result of */ | |
442 | /* the conversion */ | |
443 | /* *string is the character string which should contain a valid */ | |
444 | /* number (which may be a special value) */ | |
87d32bb7 | 445 | /* set is the context */ |
f5bc1778 DJ |
446 | /* */ |
447 | /* The context is supplied to this routine is used for error handling */ | |
448 | /* (setting of status and traps) and for the rounding mode, only. */ | |
449 | /* If an error occurs, the result will be a valid decimal64 NaN. */ | |
450 | /* ------------------------------------------------------------------ */ | |
451 | decimal64 * decimal64FromString(decimal64 *result, const char *string, | |
452 | decContext *set) { | |
453 | decContext dc; /* work */ | |
87d32bb7 | 454 | decNumber dn; /* .. */ |
f5bc1778 DJ |
455 | |
456 | decContextDefault(&dc, DEC_INIT_DECIMAL64); /* no traps, please */ | |
457 | dc.round=set->round; /* use supplied rounding */ | |
458 | ||
459 | decNumberFromString(&dn, string, &dc); /* will round if needed */ | |
460 | ||
461 | decimal64FromNumber(result, &dn, &dc); | |
462 | if (dc.status!=0) { /* something happened */ | |
463 | decContextSetStatus(set, dc.status); /* .. pass it on */ | |
464 | } | |
465 | return result; | |
466 | } /* decimal64FromString */ | |
467 | ||
468 | /* ------------------------------------------------------------------ */ | |
469 | /* decimal64IsCanonical -- test whether encoding is canonical */ | |
470 | /* d64 is the source decimal64 */ | |
87d32bb7 | 471 | /* returns 1 if the encoding of d64 is canonical, 0 otherwise */ |
f5bc1778 DJ |
472 | /* No error is possible. */ |
473 | /* ------------------------------------------------------------------ */ | |
87d32bb7 DD |
474 | uInt decimal64IsCanonical(const decimal64 *d64) { |
475 | decNumber dn; /* work */ | |
f5bc1778 DJ |
476 | decimal64 canon; /* .. */ |
477 | decContext dc; /* .. */ | |
478 | decContextDefault(&dc, DEC_INIT_DECIMAL64); | |
479 | decimal64ToNumber(d64, &dn); | |
480 | decimal64FromNumber(&canon, &dn, &dc);/* canon will now be canonical */ | |
481 | return memcmp(d64, &canon, DECIMAL64_Bytes)==0; | |
482 | } /* decimal64IsCanonical */ | |
483 | ||
484 | /* ------------------------------------------------------------------ */ | |
485 | /* decimal64Canonical -- copy an encoding, ensuring it is canonical */ | |
486 | /* d64 is the source decimal64 */ | |
487 | /* result is the target (may be the same decimal64) */ | |
488 | /* returns result */ | |
489 | /* No error is possible. */ | |
490 | /* ------------------------------------------------------------------ */ | |
491 | decimal64 * decimal64Canonical(decimal64 *result, const decimal64 *d64) { | |
87d32bb7 | 492 | decNumber dn; /* work */ |
f5bc1778 DJ |
493 | decContext dc; /* .. */ |
494 | decContextDefault(&dc, DEC_INIT_DECIMAL64); | |
495 | decimal64ToNumber(d64, &dn); | |
496 | decimal64FromNumber(result, &dn, &dc);/* result will now be canonical */ | |
497 | return result; | |
498 | } /* decimal64Canonical */ | |
499 | ||
500 | #if DECTRACE || DECCHECK | |
501 | /* Macros for accessing decimal64 fields. These assume the | |
502 | argument is a reference (pointer) to the decimal64 structure, | |
503 | and the decimal64 is in network byte order (big-endian) */ | |
504 | /* Get sign */ | |
505 | #define decimal64Sign(d) ((unsigned)(d)->bytes[0]>>7) | |
506 | ||
507 | /* Get combination field */ | |
508 | #define decimal64Comb(d) (((d)->bytes[0] & 0x7c)>>2) | |
509 | ||
510 | /* Get exponent continuation [does not remove bias] */ | |
511 | #define decimal64ExpCon(d) ((((d)->bytes[0] & 0x03)<<6) \ | |
512 | | ((unsigned)(d)->bytes[1]>>2)) | |
513 | ||
514 | /* Set sign [this assumes sign previously 0] */ | |
515 | #define decimal64SetSign(d, b) { \ | |
516 | (d)->bytes[0]|=((unsigned)(b)<<7);} | |
517 | ||
518 | /* Set exponent continuation [does not apply bias] */ | |
519 | /* This assumes range has been checked and exponent previously 0; */ | |
520 | /* type of exponent must be unsigned */ | |
521 | #define decimal64SetExpCon(d, e) { \ | |
87d32bb7 DD |
522 | (d)->bytes[0]|=(uByte)((e)>>6); \ |
523 | (d)->bytes[1]|=(uByte)(((e)&0x3F)<<2);} | |
f5bc1778 DJ |
524 | |
525 | /* ------------------------------------------------------------------ */ | |
526 | /* decimal64Show -- display a decimal64 in hexadecimal [debug aid] */ | |
527 | /* d64 -- the number to show */ | |
528 | /* ------------------------------------------------------------------ */ | |
529 | /* Also shows sign/cob/expconfields extracted */ | |
530 | void decimal64Show(const decimal64 *d64) { | |
531 | char buf[DECIMAL64_Bytes*2+1]; | |
532 | Int i, j=0; | |
533 | ||
534 | if (DECLITEND) { | |
535 | for (i=0; i<DECIMAL64_Bytes; i++, j+=2) { | |
536 | sprintf(&buf[j], "%02x", d64->bytes[7-i]); | |
537 | } | |
538 | printf(" D64> %s [S:%d Cb:%02x Ec:%02x] LittleEndian\n", buf, | |
539 | d64->bytes[7]>>7, (d64->bytes[7]>>2)&0x1f, | |
540 | ((d64->bytes[7]&0x3)<<6)| (d64->bytes[6]>>2)); | |
541 | } | |
542 | else { /* big-endian */ | |
543 | for (i=0; i<DECIMAL64_Bytes; i++, j+=2) { | |
544 | sprintf(&buf[j], "%02x", d64->bytes[i]); | |
545 | } | |
546 | printf(" D64> %s [S:%d Cb:%02x Ec:%02x] BigEndian\n", buf, | |
547 | decimal64Sign(d64), decimal64Comb(d64), decimal64ExpCon(d64)); | |
548 | } | |
549 | } /* decimal64Show */ | |
550 | #endif | |
551 | ||
552 | /* ================================================================== */ | |
553 | /* Shared utility routines and tables */ | |
554 | /* ================================================================== */ | |
555 | /* define and include the conversion tables to use for shared code */ | |
556 | #if DECDPUN==3 | |
557 | #define DEC_DPD2BIN 1 | |
558 | #else | |
559 | #define DEC_DPD2BCD 1 | |
560 | #endif | |
561 | #include "decDPD.h" /* lookup tables */ | |
562 | ||
563 | /* The maximum number of decNumberUnits needed for a working copy of */ | |
564 | /* the units array is the ceiling of digits/DECDPUN, where digits is */ | |
565 | /* the maximum number of digits in any of the formats for which this */ | |
566 | /* is used. decimal128.h must not be included in this module, so, as */ | |
567 | /* a very special case, that number is defined as a literal here. */ | |
568 | #define DECMAX754 34 | |
569 | #define DECMAXUNITS ((DECMAX754+DECDPUN-1)/DECDPUN) | |
570 | ||
571 | /* ------------------------------------------------------------------ */ | |
572 | /* Combination field lookup tables (uInts to save measurable work) */ | |
573 | /* */ | |
574 | /* COMBEXP - 2-bit most-significant-bits of exponent */ | |
575 | /* [11 if an Infinity or NaN] */ | |
576 | /* COMBMSD - 4-bit most-significant-digit */ | |
577 | /* [0=Infinity, 1=NaN if COMBEXP=11] */ | |
578 | /* */ | |
579 | /* Both are indexed by the 5-bit combination field (0-31) */ | |
580 | /* ------------------------------------------------------------------ */ | |
581 | const uInt COMBEXP[32]={0, 0, 0, 0, 0, 0, 0, 0, | |
582 | 1, 1, 1, 1, 1, 1, 1, 1, | |
583 | 2, 2, 2, 2, 2, 2, 2, 2, | |
584 | 0, 0, 1, 1, 2, 2, 3, 3}; | |
585 | const uInt COMBMSD[32]={0, 1, 2, 3, 4, 5, 6, 7, | |
586 | 0, 1, 2, 3, 4, 5, 6, 7, | |
587 | 0, 1, 2, 3, 4, 5, 6, 7, | |
588 | 8, 9, 8, 9, 8, 9, 0, 1}; | |
589 | ||
590 | /* ------------------------------------------------------------------ */ | |
591 | /* decDigitsToDPD -- pack coefficient into DPD form */ | |
592 | /* */ | |
87d32bb7 | 593 | /* dn is the source number (assumed valid, max DECMAX754 digits) */ |
f5bc1778 | 594 | /* targ is 1, 2, or 4-element uInt array, which the caller must */ |
87d32bb7 | 595 | /* have cleared to zeros */ |
f5bc1778 DJ |
596 | /* shift is the number of 0 digits to add on the right (normally 0) */ |
597 | /* */ | |
87d32bb7 | 598 | /* The coefficient must be known small enough to fit. The full */ |
f5bc1778 DJ |
599 | /* coefficient is copied, including the leading 'odd' digit. This */ |
600 | /* digit is retrieved and packed into the combination field by the */ | |
601 | /* caller. */ | |
602 | /* */ | |
603 | /* The target uInts are altered only as necessary to receive the */ | |
604 | /* digits of the decNumber. When more than one uInt is needed, they */ | |
605 | /* are filled from left to right (that is, the uInt at offset 0 will */ | |
606 | /* end up with the least-significant digits). */ | |
607 | /* */ | |
608 | /* shift is used for 'fold-down' padding. */ | |
609 | /* */ | |
610 | /* No error is possible. */ | |
611 | /* ------------------------------------------------------------------ */ | |
612 | #if DECDPUN<=4 | |
613 | /* Constant multipliers for divide-by-power-of five using reciprocal */ | |
614 | /* multiply, after removing powers of 2 by shifting, and final shift */ | |
615 | /* of 17 [we only need up to **4] */ | |
616 | static const uInt multies[]={131073, 26215, 5243, 1049, 210}; | |
617 | /* QUOT10 -- macro to return the quotient of unit u divided by 10**n */ | |
618 | #define QUOT10(u, n) ((((uInt)(u)>>(n))*multies[n])>>17) | |
619 | #endif | |
620 | void decDigitsToDPD(const decNumber *dn, uInt *targ, Int shift) { | |
621 | Int cut; /* work */ | |
622 | Int n; /* output bunch counter */ | |
623 | Int digits=dn->digits; /* digit countdown */ | |
624 | uInt dpd; /* densely packed decimal value */ | |
625 | uInt bin; /* binary value 0-999 */ | |
626 | uInt *uout=targ; /* -> current output uInt */ | |
87d32bb7 | 627 | uInt uoff=0; /* -> current output offset [from right] */ |
f5bc1778 DJ |
628 | const Unit *inu=dn->lsu; /* -> current input unit */ |
629 | Unit uar[DECMAXUNITS]; /* working copy of units, iff shifted */ | |
630 | #if DECDPUN!=3 /* not fast path */ | |
631 | Unit in; /* current unit */ | |
632 | #endif | |
633 | ||
634 | if (shift!=0) { /* shift towards most significant required */ | |
635 | /* shift the units array to the left by pad digits and copy */ | |
636 | /* [this code is a special case of decShiftToMost, which could */ | |
637 | /* be used instead if exposed and the array were copied first] */ | |
87d32bb7 | 638 | const Unit *source; /* .. */ |
f5bc1778 DJ |
639 | Unit *target, *first; /* .. */ |
640 | uInt next=0; /* work */ | |
641 | ||
642 | source=dn->lsu+D2U(digits)-1; /* where msu comes from */ | |
643 | target=uar+D2U(digits)-1+D2U(shift);/* where upper part of first cut goes */ | |
644 | cut=DECDPUN-MSUDIGITS(shift); /* where to slice */ | |
645 | if (cut==0) { /* unit-boundary case */ | |
646 | for (; source>=dn->lsu; source--, target--) *target=*source; | |
647 | } | |
648 | else { | |
649 | first=uar+D2U(digits+shift)-1; /* where msu will end up */ | |
650 | for (; source>=dn->lsu; source--, target--) { | |
651 | /* split the source Unit and accumulate remainder for next */ | |
652 | #if DECDPUN<=4 | |
653 | uInt quot=QUOT10(*source, cut); | |
654 | uInt rem=*source-quot*DECPOWERS[cut]; | |
655 | next+=quot; | |
656 | #else | |
657 | uInt rem=*source%DECPOWERS[cut]; | |
658 | next+=*source/DECPOWERS[cut]; | |
659 | #endif | |
660 | if (target<=first) *target=(Unit)next; /* write to target iff valid */ | |
661 | next=rem*DECPOWERS[DECDPUN-cut]; /* save remainder for next Unit */ | |
662 | } | |
663 | } /* shift-move */ | |
664 | /* propagate remainder to one below and clear the rest */ | |
665 | for (; target>=uar; target--) { | |
666 | *target=(Unit)next; | |
667 | next=0; | |
668 | } | |
669 | digits+=shift; /* add count (shift) of zeros added */ | |
670 | inu=uar; /* use units in working array */ | |
671 | } | |
672 | ||
673 | /* now densely pack the coefficient into DPD declets */ | |
674 | ||
675 | #if DECDPUN!=3 /* not fast path */ | |
676 | in=*inu; /* current unit */ | |
677 | cut=0; /* at lowest digit */ | |
678 | bin=0; /* [keep compiler quiet] */ | |
679 | #endif | |
680 | ||
681 | for(n=0; digits>0; n++) { /* each output bunch */ | |
682 | #if DECDPUN==3 /* fast path, 3-at-a-time */ | |
87d32bb7 | 683 | bin=*inu; /* 3 digits ready for convert */ |
f5bc1778 DJ |
684 | digits-=3; /* [may go negative] */ |
685 | inu++; /* may need another */ | |
686 | ||
687 | #else /* must collect digit-by-digit */ | |
87d32bb7 | 688 | Unit dig; /* current digit */ |
f5bc1778 DJ |
689 | Int j; /* digit-in-declet count */ |
690 | for (j=0; j<3; j++) { | |
691 | #if DECDPUN<=4 | |
692 | Unit temp=(Unit)((uInt)(in*6554)>>16); | |
693 | dig=(Unit)(in-X10(temp)); | |
694 | in=temp; | |
695 | #else | |
696 | dig=in%10; | |
697 | in=in/10; | |
698 | #endif | |
699 | if (j==0) bin=dig; | |
87d32bb7 | 700 | else if (j==1) bin+=X10(dig); |
f5bc1778 DJ |
701 | else /* j==2 */ bin+=X100(dig); |
702 | digits--; | |
703 | if (digits==0) break; /* [also protects *inu below] */ | |
704 | cut++; | |
705 | if (cut==DECDPUN) {inu++; in=*inu; cut=0;} | |
706 | } | |
707 | #endif | |
708 | /* here there are 3 digits in bin, or have used all input digits */ | |
709 | ||
710 | dpd=BIN2DPD[bin]; | |
711 | ||
712 | /* write declet to uInt array */ | |
713 | *uout|=dpd<<uoff; | |
714 | uoff+=10; | |
715 | if (uoff<32) continue; /* no uInt boundary cross */ | |
716 | uout++; | |
717 | uoff-=32; | |
718 | *uout|=dpd>>(10-uoff); /* collect top bits */ | |
719 | } /* n declets */ | |
720 | return; | |
721 | } /* decDigitsToDPD */ | |
722 | ||
723 | /* ------------------------------------------------------------------ */ | |
724 | /* decDigitsFromDPD -- unpack a format's coefficient */ | |
725 | /* */ | |
726 | /* dn is the target number, with 7, 16, or 34-digit space. */ | |
727 | /* sour is a 1, 2, or 4-element uInt array containing only declets */ | |
728 | /* declets is the number of (right-aligned) declets in sour to */ | |
729 | /* be processed. This may be 1 more than the obvious number in */ | |
730 | /* a format, as any top digit is prefixed to the coefficient */ | |
731 | /* continuation field. It also may be as small as 1, as the */ | |
732 | /* caller may pre-process leading zero declets. */ | |
733 | /* */ | |
734 | /* When doing the 'extra declet' case care is taken to avoid writing */ | |
735 | /* extra digits when there are leading zeros, as these could overflow */ | |
736 | /* the units array when DECDPUN is not 3. */ | |
737 | /* */ | |
738 | /* The target uInts are used only as necessary to process declets */ | |
739 | /* declets into the decNumber. When more than one uInt is needed, */ | |
740 | /* they are used from left to right (that is, the uInt at offset 0 */ | |
741 | /* provides the least-significant digits). */ | |
742 | /* */ | |
743 | /* dn->digits is set, but not the sign or exponent. */ | |
744 | /* No error is possible [the redundant 888 codes are allowed]. */ | |
745 | /* ------------------------------------------------------------------ */ | |
746 | void decDigitsFromDPD(decNumber *dn, const uInt *sour, Int declets) { | |
747 | ||
748 | uInt dpd; /* collector for 10 bits */ | |
749 | Int n; /* counter */ | |
750 | Unit *uout=dn->lsu; /* -> current output unit */ | |
751 | Unit *last=uout; /* will be unit containing msd */ | |
87d32bb7 DD |
752 | const uInt *uin=sour; /* -> current input uInt */ |
753 | uInt uoff=0; /* -> current input offset [from right] */ | |
f5bc1778 DJ |
754 | |
755 | #if DECDPUN!=3 | |
756 | uInt bcd; /* BCD result */ | |
87d32bb7 | 757 | uInt nibble; /* work */ |
f5bc1778 DJ |
758 | Unit out=0; /* accumulator */ |
759 | Int cut=0; /* power of ten in current unit */ | |
760 | #endif | |
761 | #if DECDPUN>4 | |
762 | uInt const *pow; /* work */ | |
763 | #endif | |
764 | ||
765 | /* Expand the densely-packed integer, right to left */ | |
766 | for (n=declets-1; n>=0; n--) { /* count down declets of 10 bits */ | |
767 | dpd=*uin>>uoff; | |
768 | uoff+=10; | |
769 | if (uoff>32) { /* crossed uInt boundary */ | |
770 | uin++; | |
771 | uoff-=32; | |
772 | dpd|=*uin<<(10-uoff); /* get waiting bits */ | |
773 | } | |
87d32bb7 | 774 | dpd&=0x3ff; /* clear uninteresting bits */ |
f5bc1778 DJ |
775 | |
776 | #if DECDPUN==3 | |
777 | if (dpd==0) *uout=0; | |
778 | else { | |
779 | *uout=DPD2BIN[dpd]; /* convert 10 bits to binary 0-999 */ | |
780 | last=uout; /* record most significant unit */ | |
781 | } | |
782 | uout++; | |
783 | } /* n */ | |
784 | ||
785 | #else /* DECDPUN!=3 */ | |
786 | if (dpd==0) { /* fastpath [e.g., leading zeros] */ | |
787 | /* write out three 0 digits (nibbles); out may have digit(s) */ | |
788 | cut++; | |
789 | if (cut==DECDPUN) {*uout=out; if (out) {last=uout; out=0;} uout++; cut=0;} | |
790 | if (n==0) break; /* [as below, works even if MSD=0] */ | |
791 | cut++; | |
792 | if (cut==DECDPUN) {*uout=out; if (out) {last=uout; out=0;} uout++; cut=0;} | |
793 | cut++; | |
794 | if (cut==DECDPUN) {*uout=out; if (out) {last=uout; out=0;} uout++; cut=0;} | |
795 | continue; | |
796 | } | |
797 | ||
798 | bcd=DPD2BCD[dpd]; /* convert 10 bits to 12 bits BCD */ | |
799 | ||
800 | /* now accumulate the 3 BCD nibbles into units */ | |
801 | nibble=bcd & 0x00f; | |
802 | if (nibble) out=(Unit)(out+nibble*DECPOWERS[cut]); | |
803 | cut++; | |
804 | if (cut==DECDPUN) {*uout=out; if (out) {last=uout; out=0;} uout++; cut=0;} | |
805 | bcd>>=4; | |
806 | ||
807 | /* if this is the last declet and the remaining nibbles in bcd */ | |
808 | /* are 00 then process no more nibbles, because this could be */ | |
809 | /* the 'odd' MSD declet and writing any more Units would then */ | |
810 | /* overflow the unit array */ | |
811 | if (n==0 && !bcd) break; | |
812 | ||
813 | nibble=bcd & 0x00f; | |
814 | if (nibble) out=(Unit)(out+nibble*DECPOWERS[cut]); | |
815 | cut++; | |
816 | if (cut==DECDPUN) {*uout=out; if (out) {last=uout; out=0;} uout++; cut=0;} | |
817 | bcd>>=4; | |
818 | ||
819 | nibble=bcd & 0x00f; | |
820 | if (nibble) out=(Unit)(out+nibble*DECPOWERS[cut]); | |
821 | cut++; | |
822 | if (cut==DECDPUN) {*uout=out; if (out) {last=uout; out=0;} uout++; cut=0;} | |
823 | } /* n */ | |
87d32bb7 | 824 | if (cut!=0) { /* some more left over */ |
f5bc1778 | 825 | *uout=out; /* write out final unit */ |
87d32bb7 | 826 | if (out) last=uout; /* and note if non-zero */ |
f5bc1778 DJ |
827 | } |
828 | #endif | |
829 | ||
830 | /* here, last points to the most significant unit with digits; */ | |
831 | /* inspect it to get the final digits count -- this is essentially */ | |
832 | /* the same code as decGetDigits in decNumber.c */ | |
833 | dn->digits=(last-dn->lsu)*DECDPUN+1; /* floor of digits, plus */ | |
834 | /* must be at least 1 digit */ | |
835 | #if DECDPUN>1 | |
87d32bb7 DD |
836 | if (*last<10) return; /* common odd digit or 0 */ |
837 | dn->digits++; /* must be 2 at least */ | |
f5bc1778 DJ |
838 | #if DECDPUN>2 |
839 | if (*last<100) return; /* 10-99 */ | |
87d32bb7 | 840 | dn->digits++; /* must be 3 at least */ |
f5bc1778 DJ |
841 | #if DECDPUN>3 |
842 | if (*last<1000) return; /* 100-999 */ | |
87d32bb7 | 843 | dn->digits++; /* must be 4 at least */ |
f5bc1778 DJ |
844 | #if DECDPUN>4 |
845 | for (pow=&DECPOWERS[4]; *last>=*pow; pow++) dn->digits++; | |
846 | #endif | |
847 | #endif | |
848 | #endif | |
849 | #endif | |
850 | return; | |
851 | } /*decDigitsFromDPD */ |