Update.
[kopensolaris-gnu/glibc.git] / stdio-common / _itoa.c
1 /* Internal function for converting integers to ASCII.
2    Copyright (C) 1994, 1995, 1996, 1999, 2000, 2002, 2003, 2004
3    Free Software Foundation, Inc.
4    This file is part of the GNU C Library.
5    Contributed by Torbjorn Granlund <tege@matematik.su.se>
6    and Ulrich Drepper <drepper@gnu.org>.
7
8    The GNU C Library is free software; you can redistribute it and/or
9    modify it under the terms of the GNU Lesser General Public
10    License as published by the Free Software Foundation; either
11    version 2.1 of the License, or (at your option) any later version.
12
13    The GNU C Library is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16    Lesser General Public License for more details.
17
18    You should have received a copy of the GNU Lesser General Public
19    License along with the GNU C Library; if not, write to the Free
20    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
21    02111-1307 USA.  */
22
23 #include <gmp-mparam.h>
24 #include <gmp.h>
25 #include <stdlib/gmp-impl.h>
26 #include <stdlib/longlong.h>
27
28 #include "_itoa.h"
29
30
31 /* Canonize environment.  For some architectures not all values might
32    be defined in the GMP header files.  */
33 #ifndef UMUL_TIME
34 # define UMUL_TIME 1
35 #endif
36 #ifndef UDIV_TIME
37 # define UDIV_TIME 3
38 #endif
39
40 /* Control memory layout.  */
41 #ifdef PACK
42 # undef PACK
43 # define PACK __attribute__ ((packed))
44 #else
45 # define PACK
46 #endif
47
48
49 /* Declare local types.  */
50 struct base_table_t
51 {
52 #if (UDIV_TIME > 2 * UMUL_TIME)
53   mp_limb_t base_multiplier;
54 #endif
55   char flag;
56   char post_shift;
57 #if BITS_PER_MP_LIMB == 32
58   struct
59     {
60       char normalization_steps;
61       char ndigits;
62       mp_limb_t base PACK;
63 #if UDIV_TIME > 2 * UMUL_TIME
64       mp_limb_t base_ninv PACK;
65 #endif
66     } big;
67 #endif
68 };
69
70 /* To reduce the memory needed we include some fields of the tables
71    only conditionally.  */
72 #if UDIV_TIME > 2 * UMUL_TIME
73 # define SEL1(X) X,
74 # define SEL2(X) ,X
75 #else
76 # define SEL1(X)
77 # define SEL2(X)
78 #endif
79
80
81 /* Local variables.  */
82 const struct base_table_t _itoa_base_table[] attribute_hidden =
83 {
84 #if BITS_PER_MP_LIMB == 64
85   /*  2 */ {SEL1(0ull) 1, 1},
86   /*  3 */ {SEL1(0xaaaaaaaaaaaaaaabull) 0, 1},
87   /*  4 */ {SEL1(0ull) 1, 2},
88   /*  5 */ {SEL1(0xcccccccccccccccdull) 0, 2},
89   /*  6 */ {SEL1(0xaaaaaaaaaaaaaaabull) 0, 2},
90   /*  7 */ {SEL1(0x2492492492492493ull) 1, 3},
91   /*  8 */ {SEL1(0ull) 1, 3},
92   /*  9 */ {SEL1(0xe38e38e38e38e38full) 0, 3},
93   /* 10 */ {SEL1(0xcccccccccccccccdull) 0, 3},
94   /* 11 */ {SEL1(0x2e8ba2e8ba2e8ba3ull) 0, 1},
95   /* 12 */ {SEL1(0xaaaaaaaaaaaaaaabull) 0, 3},
96   /* 13 */ {SEL1(0x4ec4ec4ec4ec4ec5ull) 0, 2},
97   /* 14 */ {SEL1(0x2492492492492493ull) 1, 4},
98   /* 15 */ {SEL1(0x8888888888888889ull) 0, 3},
99   /* 16 */ {SEL1(0ull) 1, 4},
100   /* 17 */ {SEL1(0xf0f0f0f0f0f0f0f1ull) 0, 4},
101   /* 18 */ {SEL1(0xe38e38e38e38e38full) 0, 4},
102   /* 19 */ {SEL1(0xd79435e50d79435full) 0, 4},
103   /* 20 */ {SEL1(0xcccccccccccccccdull) 0, 4},
104   /* 21 */ {SEL1(0x8618618618618619ull) 1, 5},
105   /* 22 */ {SEL1(0x2e8ba2e8ba2e8ba3ull) 0, 2},
106   /* 23 */ {SEL1(0x642c8590b21642c9ull) 1, 5},
107   /* 24 */ {SEL1(0xaaaaaaaaaaaaaaabull) 0, 4},
108   /* 25 */ {SEL1(0x47ae147ae147ae15ull) 1, 5},
109   /* 26 */ {SEL1(0x4ec4ec4ec4ec4ec5ull) 0, 3},
110   /* 27 */ {SEL1(0x97b425ed097b425full) 0, 4},
111   /* 28 */ {SEL1(0x2492492492492493ull) 1, 5},
112   /* 29 */ {SEL1(0x1a7b9611a7b9611bull) 1, 5},
113   /* 30 */ {SEL1(0x8888888888888889ull) 0, 4},
114   /* 31 */ {SEL1(0x0842108421084211ull) 1, 5},
115   /* 32 */ {SEL1(0ull) 1, 5},
116   /* 33 */ {SEL1(0x0f83e0f83e0f83e1ull) 0, 1},
117   /* 34 */ {SEL1(0xf0f0f0f0f0f0f0f1ull) 0, 5},
118   /* 35 */ {SEL1(0xea0ea0ea0ea0ea0full) 0, 5},
119   /* 36 */ {SEL1(0xe38e38e38e38e38full) 0, 5}
120 #endif
121 #if BITS_PER_MP_LIMB == 32
122   /*  2 */ {SEL1(0ul) 1, 1, {0, 31, 0x80000000ul SEL2(0xfffffffful)}},
123   /*  3 */ {SEL1(0xaaaaaaabul) 0, 1, {0, 20, 0xcfd41b91ul SEL2(0x3b563c24ul)}},
124   /*  4 */ {SEL1(0ul) 1, 2, {1, 15, 0x40000000ul SEL2(0xfffffffful)}},
125   /*  5 */ {SEL1(0xcccccccdul) 0, 2, {1, 13, 0x48c27395ul SEL2(0xc25c2684ul)}},
126   /*  6 */ {SEL1(0xaaaaaaabul) 0, 2, {0, 12, 0x81bf1000ul SEL2(0xf91bd1b6ul)}},
127   /*  7 */ {SEL1(0x24924925ul) 1, 3, {1, 11, 0x75db9c97ul SEL2(0x1607a2cbul)}},
128   /*  8 */ {SEL1(0ul) 1, 3, {1, 10, 0x40000000ul SEL2(0xfffffffful)}},
129   /*  9 */ {SEL1(0x38e38e39ul) 0, 1, {0, 10, 0xcfd41b91ul SEL2(0x3b563c24ul)}},
130   /* 10 */ {SEL1(0xcccccccdul) 0, 3, {2, 9, 0x3b9aca00ul SEL2(0x12e0be82ul)}},
131   /* 11 */ {SEL1(0xba2e8ba3ul) 0, 3, {0, 9, 0x8c8b6d2bul SEL2(0xd24cde04ul)}},
132   /* 12 */ {SEL1(0xaaaaaaabul) 0, 3, {3, 8, 0x19a10000ul SEL2(0x3fa39ab5ul)}},
133   /* 13 */ {SEL1(0x4ec4ec4ful) 0, 2, {2, 8, 0x309f1021ul SEL2(0x50f8ac5ful)}},
134   /* 14 */ {SEL1(0x24924925ul) 1, 4, {1, 8, 0x57f6c100ul SEL2(0x74843b1eul)}},
135   /* 15 */ {SEL1(0x88888889ul) 0, 3, {0, 8, 0x98c29b81ul SEL2(0xad0326c2ul)}},
136   /* 16 */ {SEL1(0ul) 1, 4, {3, 7, 0x10000000ul SEL2(0xfffffffful)}},
137   /* 17 */ {SEL1(0xf0f0f0f1ul) 0, 4, {3, 7, 0x18754571ul SEL2(0x4ef0b6bdul)}},
138   /* 18 */ {SEL1(0x38e38e39ul) 0, 2, {2, 7, 0x247dbc80ul SEL2(0xc0fc48a1ul)}},
139   /* 19 */ {SEL1(0xaf286bcbul) 1, 5, {2, 7, 0x3547667bul SEL2(0x33838942ul)}},
140   /* 20 */ {SEL1(0xcccccccdul) 0, 4, {1, 7, 0x4c4b4000ul SEL2(0xad7f29abul)}},
141   /* 21 */ {SEL1(0x86186187ul) 1, 5, {1, 7, 0x6b5a6e1dul SEL2(0x313c3d15ul)}},
142   /* 22 */ {SEL1(0xba2e8ba3ul) 0, 4, {0, 7, 0x94ace180ul SEL2(0xb8cca9e0ul)}},
143   /* 23 */ {SEL1(0xb21642c9ul) 0, 4, {0, 7, 0xcaf18367ul SEL2(0x42ed6de9ul)}},
144   /* 24 */ {SEL1(0xaaaaaaabul) 0, 4, {4, 6, 0x0b640000ul SEL2(0x67980e0bul)}},
145   /* 25 */ {SEL1(0x51eb851ful) 0, 3, {4, 6, 0x0e8d4a51ul SEL2(0x19799812ul)}},
146   /* 26 */ {SEL1(0x4ec4ec4ful) 0, 3, {3, 6, 0x1269ae40ul SEL2(0xbce85396ul)}},
147   /* 27 */ {SEL1(0x2f684bdbul) 1, 5, {3, 6, 0x17179149ul SEL2(0x62c103a9ul)}},
148   /* 28 */ {SEL1(0x24924925ul) 1, 5, {3, 6, 0x1cb91000ul SEL2(0x1d353d43ul)}},
149   /* 29 */ {SEL1(0x8d3dcb09ul) 0, 4, {2, 6, 0x23744899ul SEL2(0xce1deceaul)}},
150   /* 30 */ {SEL1(0x88888889ul) 0, 4, {2, 6, 0x2b73a840ul SEL2(0x790fc511ul)}},
151   /* 31 */ {SEL1(0x08421085ul) 1, 5, {2, 6, 0x34e63b41ul SEL2(0x35b865a0ul)}},
152   /* 32 */ {SEL1(0ul) 1, 5, {1, 6, 0x40000000ul SEL2(0xfffffffful)}},
153   /* 33 */ {SEL1(0x3e0f83e1ul) 0, 3, {1, 6, 0x4cfa3cc1ul SEL2(0xa9aed1b3ul)}},
154   /* 34 */ {SEL1(0xf0f0f0f1ul) 0, 5, {1, 6, 0x5c13d840ul SEL2(0x63dfc229ul)}},
155   /* 35 */ {SEL1(0xd41d41d5ul) 1, 6, {1, 6, 0x6d91b519ul SEL2(0x2b0fee30ul)}},
156   /* 36 */ {SEL1(0x38e38e39ul) 0, 3, {0, 6, 0x81bf1000ul SEL2(0xf91bd1b6ul)}}
157 #endif
158 };
159
160 /* Lower-case digits.  */
161 extern const char _itoa_lower_digits[];
162 extern const char _itoa_lower_digits_internal[] attribute_hidden;
163 /* Upper-case digits.  */
164 extern const char _itoa_upper_digits[];
165 extern const char _itoa_upper_digits_internal[] attribute_hidden;
166
167
168 char *
169 _itoa_word (unsigned long value, char *buflim,
170             unsigned int base, int upper_case)
171 {
172   const char *digits = (upper_case
173 #if !defined NOT_IN_libc || defined IS_IN_rtld
174                         ? INTUSE(_itoa_upper_digits)
175                         : INTUSE(_itoa_lower_digits)
176 #else
177                         ? _itoa_upper_digits
178                         : _itoa_lower_digits
179 #endif
180                        );
181
182   switch (base)
183     {
184 #define SPECIAL(Base)                                                         \
185     case Base:                                                                \
186       do                                                                      \
187         *--buflim = digits[value % Base];                                     \
188       while ((value /= Base) != 0);                                           \
189       break
190
191       SPECIAL (10);
192       SPECIAL (16);
193       SPECIAL (8);
194     default:
195       do
196         *--buflim = digits[value % base];
197       while ((value /= base) != 0);
198     }
199   return buflim;
200 }
201 #undef SPECIAL
202
203
204 char *
205 _itoa (value, buflim, base, upper_case)
206      unsigned long long int value;
207      char *buflim;
208      unsigned int base;
209      int upper_case;
210 {
211   const char *digits = (upper_case
212                         ? INTUSE(_itoa_upper_digits)
213                         : INTUSE(_itoa_lower_digits));
214   const struct base_table_t *brec = &_itoa_base_table[base - 2];
215
216   switch (base)
217     {
218 #define RUN_2N(BITS) \
219       do                                                                      \
220         {                                                                     \
221           /* `unsigned long long int' always has 64 bits.  */                 \
222           mp_limb_t work_hi = value >> (64 - BITS_PER_MP_LIMB);               \
223                                                                               \
224           if (BITS_PER_MP_LIMB == 32)                                         \
225             {                                                                 \
226               if (work_hi != 0)                                               \
227                 {                                                             \
228                   mp_limb_t work_lo;                                          \
229                   int cnt;                                                    \
230                                                                               \
231                   work_lo = value & 0xfffffffful;                             \
232                   for (cnt = BITS_PER_MP_LIMB / BITS; cnt > 0; --cnt)         \
233                     {                                                         \
234                       *--buflim = digits[work_lo & ((1ul << BITS) - 1)];      \
235                       work_lo >>= BITS;                                       \
236                     }                                                         \
237                   if (BITS_PER_MP_LIMB % BITS != 0)                           \
238                     {                                                         \
239                       work_lo                                                 \
240                         |= ((work_hi                                          \
241                              & ((1 << (BITS - BITS_PER_MP_LIMB%BITS))         \
242                                 - 1))                                         \
243                             << BITS_PER_MP_LIMB % BITS);                      \
244                       work_hi >>= BITS - BITS_PER_MP_LIMB % BITS;             \
245                       if (work_hi == 0)                                       \
246                         work_hi = work_lo;                                    \
247                       else                                                    \
248                         *--buflim = digits[work_lo];                          \
249                     }                                                         \
250                 }                                                             \
251               else                                                            \
252                 work_hi = value & 0xfffffffful;                               \
253             }                                                                 \
254           do                                                                  \
255             {                                                                 \
256               *--buflim = digits[work_hi & ((1 << BITS) - 1)];                \
257               work_hi >>= BITS;                                               \
258             }                                                                 \
259           while (work_hi != 0);                                               \
260         }                                                                     \
261       while (0)
262     case 8:
263       RUN_2N (3);
264       break;
265
266     case 16:
267       RUN_2N (4);
268       break;
269
270     default:
271       {
272 #if BITS_PER_MP_LIMB == 64
273         mp_limb_t base_multiplier = brec->base_multiplier;
274         if (brec->flag)
275           while (value != 0)
276             {
277               mp_limb_t quo, rem, x, dummy;
278
279               umul_ppmm (x, dummy, value, base_multiplier);
280               quo = (x + ((value - x) >> 1)) >> (brec->post_shift - 1);
281               rem = value - quo * base;
282               *--buflim = digits[rem];
283               value = quo;
284             }
285         else
286           while (value != 0)
287             {
288               mp_limb_t quo, rem, x, dummy;
289
290               umul_ppmm (x, dummy, value, base_multiplier);
291               quo = x >> brec->post_shift;
292               rem = value - quo * base;
293               *--buflim = digits[rem];
294               value = quo;
295             }
296 #endif
297 #if BITS_PER_MP_LIMB == 32
298         mp_limb_t t[3];
299         int n;
300
301         /* First convert x0 to 1-3 words in base s->big.base.
302            Optimize for frequent cases of 32 bit numbers.  */
303         if ((mp_limb_t) (value >> 32) >= 1)
304           {
305 #if UDIV_TIME > 2 * UMUL_TIME || UDIV_NEEDS_NORMALIZATION
306             int big_normalization_steps = brec->big.normalization_steps;
307             mp_limb_t big_base_norm
308               = brec->big.base << big_normalization_steps;
309 #endif
310             if ((mp_limb_t) (value >> 32) >= brec->big.base)
311               {
312                 mp_limb_t x1hi, x1lo, r;
313                 /* If you want to optimize this, take advantage of
314                    that the quotient in the first udiv_qrnnd will
315                    always be very small.  It might be faster just to
316                    subtract in a tight loop.  */
317
318 #if UDIV_TIME > 2 * UMUL_TIME
319                 mp_limb_t x, xh, xl;
320
321                 if (big_normalization_steps == 0)
322                   xh = 0;
323                 else
324                   xh = (mp_limb_t) (value >> (64 - big_normalization_steps));
325                 xl = (mp_limb_t) (value >> (32 - big_normalization_steps));
326                 udiv_qrnnd_preinv (x1hi, r, xh, xl, big_base_norm,
327                                    brec->big.base_ninv);
328
329                 xl = ((mp_limb_t) value) << big_normalization_steps;
330                 udiv_qrnnd_preinv (x1lo, x, r, xl, big_base_norm,
331                                    brec->big.base_ninv);
332                 t[2] = x >> big_normalization_steps;
333
334                 if (big_normalization_steps == 0)
335                   xh = x1hi;
336                 else
337                   xh = ((x1hi << big_normalization_steps)
338                         | (x1lo >> (32 - big_normalization_steps)));
339                 xl = x1lo << big_normalization_steps;
340                 udiv_qrnnd_preinv (t[0], x, xh, xl, big_base_norm,
341                                    brec->big.base_ninv);
342                 t[1] = x >> big_normalization_steps;
343 #elif UDIV_NEEDS_NORMALIZATION
344                 mp_limb_t x, xh, xl;
345
346                 if (big_normalization_steps == 0)
347                   xh = 0;
348                 else
349                   xh = (mp_limb_t) (value >> 64 - big_normalization_steps);
350                 xl = (mp_limb_t) (value >> 32 - big_normalization_steps);
351                 udiv_qrnnd (x1hi, r, xh, xl, big_base_norm);
352
353                 xl = ((mp_limb_t) value) << big_normalization_steps;
354                 udiv_qrnnd (x1lo, x, r, xl, big_base_norm);
355                 t[2] = x >> big_normalization_steps;
356
357                 if (big_normalization_steps == 0)
358                   xh = x1hi;
359                 else
360                   xh = ((x1hi << big_normalization_steps)
361                         | (x1lo >> 32 - big_normalization_steps));
362                 xl = x1lo << big_normalization_steps;
363                 udiv_qrnnd (t[0], x, xh, xl, big_base_norm);
364                 t[1] = x >> big_normalization_steps;
365 #else
366                 udiv_qrnnd (x1hi, r, 0, (mp_limb_t) (value >> 32),
367                             brec->big.base);
368                 udiv_qrnnd (x1lo, t[2], r, (mp_limb_t) value, brec->big.base);
369                 udiv_qrnnd (t[0], t[1], x1hi, x1lo, brec->big.base);
370 #endif
371                 n = 3;
372               }
373             else
374               {
375 #if (UDIV_TIME > 2 * UMUL_TIME)
376                 mp_limb_t x;
377
378                 value <<= brec->big.normalization_steps;
379                 udiv_qrnnd_preinv (t[0], x, (mp_limb_t) (value >> 32),
380                                    (mp_limb_t) value, big_base_norm,
381                                    brec->big.base_ninv);
382                 t[1] = x >> brec->big.normalization_steps;
383 #elif UDIV_NEEDS_NORMALIZATION
384                 mp_limb_t x;
385
386                 value <<= big_normalization_steps;
387                 udiv_qrnnd (t[0], x, (mp_limb_t) (value >> 32),
388                             (mp_limb_t) value, big_base_norm);
389                 t[1] = x >> big_normalization_steps;
390 #else
391                 udiv_qrnnd (t[0], t[1], (mp_limb_t) (value >> 32),
392                             (mp_limb_t) value, brec->big.base);
393 #endif
394                 n = 2;
395               }
396           }
397         else
398           {
399             t[0] = value;
400             n = 1;
401           }
402
403         /* Convert the 1-3 words in t[], word by word, to ASCII.  */
404         do
405           {
406             mp_limb_t ti = t[--n];
407             int ndig_for_this_limb = 0;
408
409 #if UDIV_TIME > 2 * UMUL_TIME
410             mp_limb_t base_multiplier = brec->base_multiplier;
411             if (brec->flag)
412               while (ti != 0)
413                 {
414                   mp_limb_t quo, rem, x, dummy;
415
416                   umul_ppmm (x, dummy, ti, base_multiplier);
417                   quo = (x + ((ti - x) >> 1)) >> (brec->post_shift - 1);
418                   rem = ti - quo * base;
419                   *--buflim = digits[rem];
420                   ti = quo;
421                   ++ndig_for_this_limb;
422                 }
423             else
424               while (ti != 0)
425                 {
426                   mp_limb_t quo, rem, x, dummy;
427
428                   umul_ppmm (x, dummy, ti, base_multiplier);
429                   quo = x >> brec->post_shift;
430                   rem = ti - quo * base;
431                   *--buflim = digits[rem];
432                   ti = quo;
433                   ++ndig_for_this_limb;
434                 }
435 #else
436             while (ti != 0)
437               {
438                 mp_limb_t quo, rem;
439
440                 quo = ti / base;
441                 rem = ti % base;
442                 *--buflim = digits[rem];
443                 ti = quo;
444                 ++ndig_for_this_limb;
445               }
446 #endif
447             /* If this wasn't the most significant word, pad with zeros.  */
448             if (n != 0)
449               while (ndig_for_this_limb < brec->big.ndigits)
450                 {
451                   *--buflim = '0';
452                   ++ndig_for_this_limb;
453                 }
454           }
455         while (n != 0);
456 #endif
457       }
458       break;
459     }
460
461   return buflim;
462 }
463
464 char *
465 _fitoa_word (unsigned long value, char *buf, unsigned int base, int upper_case)
466 {
467   char tmpbuf[sizeof (value) * 4];            /* Worst case length: base 2.  */
468   char *cp = _itoa_word (value, tmpbuf + sizeof (value) * 4, base, upper_case);
469   while (cp < tmpbuf + sizeof (value) * 4)
470     *buf++ = *cp++;
471   return buf;
472 }
473
474 char *
475 _fitoa (unsigned long long value, char *buf, unsigned int base, int upper_case)
476 {
477   char tmpbuf[sizeof (value) * 4];            /* Worst case length: base 2.  */
478   char *cp = _itoa (value, tmpbuf + sizeof (value) * 4, base, upper_case);
479   while (cp < tmpbuf + sizeof (value) * 4)
480     *buf++ = *cp++;
481   return buf;
482 }