Many files moved from stdio to stdio-common.
[kopensolaris-gnu/glibc.git] / stdio-common / _itoa.c
1 /* Internal function for converting integers to ASCII.
2 Copyright (C) 1994, 1995 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Torbjorn Granlund <tege@matematik.su.se>
5 and Ulrich Drepper <drepper@gnu.ai.mit.edu>.
6
7 The GNU C Library is free software; you can redistribute it and/or
8 modify it under the terms of the GNU Library General Public License as
9 published by the Free Software Foundation; either version 2 of the
10 License, or (at your option) any later version.
11
12 The GNU C Library 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 GNU
15 Library General Public License for more details.
16
17 You should have received a copy of the GNU Library General Public
18 License along with the GNU C Library; see the file COPYING.LIB.  If
19 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
20 Cambridge, MA 02139, USA.  */
21
22 #include <gmp-mparam.h>
23 #include "../stdlib/gmp.h"
24 #include "../stdlib/gmp-impl.h"
25 #include "../stdlib/longlong.h"
26
27 #include "_itoa.h"
28
29
30 /* Canonize environment.  For some architectures not all values might
31    be defined in the GMP header files.  */
32 #ifndef UMUL_TIME
33 # define UMUL_TIME 1
34 #endif
35 #ifndef UDIV_TIME
36 # define UDIV_TIME 1
37 #endif
38
39 /* Control memory layout.  */
40 #ifdef PACK
41 # undef PACK
42 # define PACK __attribute__ ((packed))
43 #else
44 # define PACK
45 #endif
46
47
48 /* Declare local types.  */
49 struct base_table_t
50 {
51 #if (UDIV_TIME > 2 * UMUL_TIME)
52   mp_limb base_multiplier;
53 #endif
54   char flag;
55   char post_shift;
56 #if BITS_PER_MP_LIMB == 32
57   struct
58     {
59       char normalization_steps;
60       char ndigits;
61       mp_limb base PACK;
62 #if UDIV_TIME > 2 * UMUL_TIME
63       mp_limb base_ninv PACK;
64 #endif
65     } big;
66 #endif
67 };
68
69 /* To reduce the memory needed we include some fields of the tables
70    only confitionally.  */
71 #if BITS_PER_MP_LIMB == 32
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 #endif
80
81
82 /* Local variables.  */
83 static const struct base_table_t base_table[] =
84 {
85 #if BITS_PER_MP_LIMB == 64
86   /*  2 */ {0ul, 1, 1},
87   /*  3 */ {0xaaaaaaaaaaaaaaabul, 0, 1},
88   /*  4 */ {0ul, 1, 2},
89   /*  5 */ {0xcccccccccccccccdul, 0, 2},
90   /*  6 */ {0xaaaaaaaaaaaaaaabul, 0, 2},
91   /*  7 */ {0x2492492492492493ul, 1, 3},
92   /*  8 */ {0ul, 1, 3},
93   /*  9 */ {0xe38e38e38e38e38ful, 0, 3},
94   /* 10 */ {0xcccccccccccccccdul, 0, 3},
95   /* 11 */ {0x2e8ba2e8ba2e8ba3ul, 0, 1},
96   /* 12 */ {0xaaaaaaaaaaaaaaabul, 0, 3},
97   /* 13 */ {0x4ec4ec4ec4ec4ec5ul, 0, 2},
98   /* 14 */ {0x2492492492492493ul, 1, 4},
99   /* 15 */ {0x8888888888888889ul, 0, 3},
100   /* 16 */ {0ul, 1, 4},
101   /* 17 */ {0xf0f0f0f0f0f0f0f1ul, 0, 4},
102   /* 18 */ {0xe38e38e38e38e38ful, 0, 4},
103   /* 19 */ {0xd79435e50d79435ful, 0, 4},
104   /* 20 */ {0xcccccccccccccccdul, 0, 4},
105   /* 21 */ {0x8618618618618619ul, 1, 5},
106   /* 22 */ {0x2e8ba2e8ba2e8ba3ul, 0, 2},
107   /* 23 */ {0x642c8590b21642c9ul, 1, 5},
108   /* 24 */ {0xaaaaaaaaaaaaaaabul, 0, 4},
109   /* 25 */ {0x47ae147ae147ae15ul, 1, 5},
110   /* 26 */ {0x4ec4ec4ec4ec4ec5ul, 0, 3},
111   /* 27 */ {0x97b425ed097b425ful, 0, 4},
112   /* 28 */ {0x2492492492492493ul, 1, 5},
113   /* 29 */ {0x1a7b9611a7b9611bul, 1, 5},
114   /* 30 */ {0x8888888888888889ul, 0, 4},
115   /* 31 */ {0x0842108421084211ul, 1, 5},
116   /* 32 */ {0ul, 1, 5},
117   /* 33 */ {0x0f83e0f83e0f83e1ul, 0, 1},
118   /* 34 */ {0xf0f0f0f0f0f0f0f1ul, 0, 5},
119   /* 35 */ {0xea0ea0ea0ea0ea0ful, 0, 5},
120   /* 36 */ {0xe38e38e38e38e38ful, 0, 5}
121 #endif
122 #if BITS_PER_MP_LIMB == 32
123   /*  2 */ {SEL1(0ul) 1, 1, {0, 31, 0x80000000ul SEL2(0xfffffffful)}},
124   /*  3 */ {SEL1(0xaaaaaaabul) 0, 1, {0, 20, 0xcfd41b91ul SEL2(0x3b563c24ul)}},
125   /*  4 */ {SEL1(0ul) 1, 2, {1, 15, 0x40000000ul SEL2(0xfffffffful)}},
126   /*  5 */ {SEL1(0xcccccccdul) 0, 2, {1, 13, 0x48c27395ul SEL2(0xc25c2684ul)}},
127   /*  6 */ {SEL1(0xaaaaaaabul) 0, 2, {0, 12, 0x81bf1000ul SEL2(0xf91bd1b6ul)}},
128   /*  7 */ {SEL1(0x24924925ul) 1, 3, {1, 11, 0x75db9c97ul SEL2(0x1607a2cbul)}},
129   /*  8 */ {SEL1(0ul) 1, 3, {1, 10, 0x40000000ul SEL2(0xfffffffful)}},
130   /*  9 */ {SEL1(0x38e38e39ul) 0, 1, {0, 10, 0xcfd41b91ul SEL2(0x3b563c24ul)}},
131   /* 10 */ {SEL1(0xcccccccdul) 0, 3, {2, 9, 0x3b9aca00ul SEL2(0x12e0be82ul)}},
132   /* 11 */ {SEL1(0xba2e8ba3ul) 0, 3, {0, 9, 0x8c8b6d2bul SEL2(0xd24cde04ul)}},
133   /* 12 */ {SEL1(0xaaaaaaabul) 0, 3, {3, 8, 0x19a10000ul SEL2(0x3fa39ab5ul)}},
134   /* 13 */ {SEL1(0x4ec4ec4ful) 0, 2, {2, 8, 0x309f1021ul SEL2(0x50f8ac5ful)}},
135   /* 14 */ {SEL1(0x24924925ul) 1, 4, {1, 8, 0x57f6c100ul SEL2(0x74843b1eul)}},
136   /* 15 */ {SEL1(0x88888889ul) 0, 3, {0, 8, 0x98c29b81ul SEL2(0xad0326c2ul)}},
137   /* 16 */ {SEL1(0ul) 1, 4, {3, 7, 0x10000000ul SEL2(0xfffffffful)}},
138   /* 17 */ {SEL1(0xf0f0f0f1ul) 0, 4, {3, 7, 0x18754571ul SEL2(0x4ef0b6bdul)}},
139   /* 18 */ {SEL1(0x38e38e39ul) 0, 2, {2, 7, 0x247dbc80ul SEL2(0xc0fc48a1ul)}},
140   /* 19 */ {SEL1(0xaf286bcbul) 1, 5, {2, 7, 0x3547667bul SEL2(0x33838942ul)}},
141   /* 20 */ {SEL1(0xcccccccdul) 0, 4, {1, 7, 0x4c4b4000ul SEL2(0xad7f29abul)}},
142   /* 21 */ {SEL1(0x86186187ul) 1, 5, {1, 7, 0x6b5a6e1dul SEL2(0x313c3d15ul)}},
143   /* 22 */ {SEL1(0xba2e8ba3ul) 0, 4, {0, 7, 0x94ace180ul SEL2(0xb8cca9e0ul)}},
144   /* 23 */ {SEL1(0xb21642c9ul) 0, 4, {0, 7, 0xcaf18367ul SEL2(0x42ed6de9ul)}},
145   /* 24 */ {SEL1(0xaaaaaaabul) 0, 4, {4, 6, 0x0b640000ul SEL2(0x67980e0bul)}},
146   /* 25 */ {SEL1(0x51eb851ful) 0, 3, {4, 6, 0x0e8d4a51ul SEL2(0x19799812ul)}},
147   /* 26 */ {SEL1(0x4ec4ec4ful) 0, 3, {3, 6, 0x1269ae40ul SEL2(0xbce85396ul)}},
148   /* 27 */ {SEL1(0x2f684bdbul) 1, 5, {3, 6, 0x17179149ul SEL2(0x62c103a9ul)}},
149   /* 28 */ {SEL1(0x24924925ul) 1, 5, {3, 6, 0x1cb91000ul SEL2(0x1d353d43ul)}},
150   /* 29 */ {SEL1(0x8d3dcb09ul) 0, 4, {2, 6, 0x23744899ul SEL2(0xce1deceaul)}},
151   /* 30 */ {SEL1(0x88888889ul) 0, 4, {2, 6, 0x2b73a840ul SEL2(0x790fc511ul)}},
152   /* 31 */ {SEL1(0x08421085ul) 1, 5, {2, 6, 0x34e63b41ul SEL2(0x35b865a0ul)}},
153   /* 32 */ {SEL1(0ul) 1, 5, {1, 6, 0x40000000ul SEL2(0xfffffffful)}},
154   /* 33 */ {SEL1(0x3e0f83e1ul) 0, 3, {1, 6, 0x4cfa3cc1ul SEL2(0xa9aed1b3ul)}},
155   /* 34 */ {SEL1(0xf0f0f0f1ul) 0, 5, {1, 6, 0x5c13d840ul SEL2(0x63dfc229ul)}},
156   /* 35 */ {SEL1(0xd41d41d5ul) 1, 6, {1, 6, 0x6d91b519ul SEL2(0x2b0fee30ul)}},
157   /* 36 */ {SEL1(0x38e38e39ul) 0, 3, {0, 6, 0x81bf1000ul SEL2(0xf91bd1b6ul)}}
158 #endif
159 };
160
161 /* Lower-case digits.  */
162 static const char _itoa_lower_digits[]
163         = "0123456789abcdefghijklmnopqrstuvwxyz";
164 /* Upper-case digits.  */
165 static const char _itoa_upper_digits[]
166         = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
167
168
169 char *
170 _itoa (value, buflim, base, upper_case)
171      unsigned long long int value;
172      char *buflim;
173      unsigned int base;
174      int upper_case;
175 {
176   const char *digits = upper_case ? _itoa_upper_digits : _itoa_lower_digits;
177   char *bp = buflim;
178   const struct base_table_t *brec = &base_table[base - 2];
179
180   switch (base)
181     {
182 #define RUN_2N(BITS)                                                      \
183       do                                                                  \
184         {                                                                 \
185           /* `unsigned long long int' always has 64 bits.  */             \
186           mp_limb work_hi = value >> (64 - BITS_PER_MP_LIMB);             \
187                                                                           \
188           if (BITS_PER_MP_LIMB == 32)                                     \
189             if (work_hi != 0)                                             \
190               {                                                           \
191                 mp_limb work_lo;                                          \
192                 int cnt;                                                  \
193                                                                           \
194                 work_lo = value & 0xfffffffful;                           \
195                 for (cnt = BITS_PER_MP_LIMB / BITS; cnt > 0; --cnt)       \
196                   {                                                       \
197                     *--bp = digits[work_lo & ((1ul << BITS) - 1)];        \
198                     work_lo >>= BITS;                                     \
199                   }                                                       \
200                 if (BITS_PER_MP_LIMB % BITS != 0)                         \
201                   {                                                       \
202                     work_lo |= ((work_hi                                  \
203                                  & ((1 << BITS - BITS_PER_MP_LIMB % BITS) \
204                                     - 1))                                 \
205                                 << BITS_PER_MP_LIMB % BITS);              \
206                     *--bp = digits[work_lo];                              \
207                     work_hi >>= BITS - BITS_PER_MP_LIMB % BITS;           \
208                   }                                                       \
209               }                                                           \
210             else                                                          \
211               work_hi = value & 0xfffffffful;                             \
212           do                                                              \
213             {                                                             \
214               *--bp = digits[work_hi & ((1 << BITS) - 1)];                \
215               work_hi >>= BITS;                                           \
216             }                                                             \
217           while (work_hi != 0);                                           \
218         }                                                                 \
219       while (0)
220     case 8:
221       RUN_2N (3);
222       break;
223
224     case 16:
225       RUN_2N (4);
226       break;
227
228     default:
229       {
230 #if BITS_PER_MP_LIMB == 64
231         mp_limb base_multiplier = brec->base_multiplier;
232         if (brec->flag)
233           while (value != 0)
234             {
235               mp_limb quo, rem, x, dummy;
236
237               umul_ppmm (x, dummy, value, base_multiplier);
238               quo = (x + ((value - x) >> 1)) >> (brec->post_shift - 1);
239               rem = value - quo * base;
240               *--bp = digits[rem];
241               value = quo;
242             }
243         else
244           while (value != 0)
245             {
246               mp_limb quo, rem, x, dummy;
247
248               umul_ppmm (x, dummy, value, base_multiplier);
249               quo = x >> brec->post_shift;
250               rem = value - quo * base;
251               *--bp = digits[rem];
252               value = quo;
253             }
254 #endif
255 #if BITS_PER_MP_LIMB == 32
256         mp_limb t[3];
257         int n;
258
259         /* First convert x0 to 1-3 words in base s->big.base.
260            Optimize for frequent cases of 32 bit numbers.  */
261         if ((mp_limb) (value >> 32) >= 1)
262           {
263             int big_normalization_steps = brec->big.normalization_steps;
264             mp_limb big_base_norm = brec->big.base << big_normalization_steps;
265
266             if ((mp_limb) (value >> 32) >= brec->big.base)
267               {
268                 mp_limb x1hi, x1lo, r;
269                 /* If you want to optimize this, take advantage of
270                    that the quotient in the first udiv_qrnnd will
271                    always be very small.  It might be faster just to
272                    subtract in a tight loop.  */
273
274 #if UDIV_TIME > 2 * UMUL_TIME
275                 mp_limb x, xh, xl;
276
277                 if (big_normalization_steps == 0)
278                   xh = 0;
279                 else
280                   xh = (mp_limb) (value >> 64 - big_normalization_steps);
281                 xl = (mp_limb) (value >> 32 - big_normalization_steps);
282                 udiv_qrnnd_preinv (x1hi, r, xh, xl, big_base_norm,
283                                    brec->big.base_ninv);
284
285                 xl = ((mp_limb) value) << big_normalization_steps;
286                 udiv_qrnnd_preinv (x1lo, x, r, xl, big_base_norm,
287                                    big_normalization_steps);
288                 t[2] = x >> big_normalization_steps;
289
290                 if (big_normalization_steps == 0)
291                   xh = x1hi;
292                 else
293                   xh = ((x1hi << big_normalization_steps)
294                         | (x1lo >> 32 - big_normalization_steps));
295                 xl = x1lo << big_normalization_steps;
296                 udiv_qrnnd_preinv (t[0], x, xh, xl, big_base_norm,
297                                    big_normalization_steps);
298                 t[1] = x >> big_normalization_steps;
299 #elif UDIV_NEEDS_NORMALIZATION
300                 mp_limb x, xh, xl;
301
302                 if (big_normalization_steps == 0)
303                   xh = 0;
304                 else
305                   xh = (mp_limb) (value >> 64 - big_normalization_steps);
306                 xl = (mp_limb) (value >> 32 - big_normalization_steps);
307                 udiv_qrnnd (x1hi, r, xh, xl, big_base_norm);
308
309                 xl = ((mp_limb) value) << big_normalization_steps;
310                 udiv_qrnnd (x1lo, x, r, xl, big_base_norm);
311                 t[2] = x >> big_normalization_steps;
312
313                 if (big_normalization_steps == 0)
314                   xh = x1hi;
315                 else
316                   xh = ((x1hi << big_normalization_steps)
317                         | (x1lo >> 32 - big_normalization_steps));
318                 xl = x1lo << big_normalization_steps;
319                 udiv_qrnnd (t[0], x, xh, xl, big_base_norm);
320                 t[1] = x >> big_normalization_steps;
321 #else
322                 udiv_qrnnd (x1hi, r, 0, (mp_limb) (value >> 32),
323                             brec->big.base);
324                 udiv_qrnnd (x1lo, t[2], r, (mp_limb) value, brec->big.base);
325                 udiv_qrnnd (t[0], t[1], x1hi, x1lo, brec->big.base);
326 #endif
327                 n = 3;
328               }
329             else
330               {
331 #if (UDIV_TIME > 2 * UMUL_TIME)
332                 mp_limb x;
333
334                 value <<= brec->big.normalization_steps;
335                 udiv_qrnnd_preinv (t[0], x, (mp_limb) (value >> 32),
336                                    (mp_limb) value, big_base_norm,
337                                    brec->big.base_ninv);
338                 t[1] = x >> brec->big.normalization_steps;
339 #elif UDIV_NEEDS_NORMALIZATION
340                 mp_limb x;
341
342                 value <<= big_normalization_steps;
343                 udiv_qrnnd (t[0], x, (mp_limb) (value >> 32),
344                             (mp_limb) value, big_base_norm);
345                 t[1] = x >> big_normalization_steps;
346 #else
347                 udiv_qrnnd (t[0], t[1], (mp_limb) (value >> 32),
348                             (mp_limb) value, brec->big.base);
349 #endif
350                 n = 2;
351               }
352           }
353         else
354           {
355             t[0] = value;
356             n = 1;
357           }
358
359         /* Convert the 1-3 words in t[], word by word, to ASCII.  */
360         do
361           {
362             mp_limb ti = t[--n];
363             int ndig_for_this_limb = 0;
364
365 #if UDIV_TIME > 2 * UMUL_TIME
366             mp_limb base_multiplier = brec->base_multiplier;
367             if (brec->flag)
368               while (ti != 0)
369                 {
370                   mp_limb quo, rem, x, dummy;
371
372                   umul_ppmm (x, dummy, ti, base_multiplier);
373                   quo = (x + ((ti - x) >> 1)) >> (brec->post_shift - 1);
374                   rem = ti - quo * base;
375                   *--bp = digits[rem];
376                   ti = quo;
377                   ++ndig_for_this_limb;
378                 }
379             else
380               while (ti != 0)
381                 {
382                   mp_limb quo, rem, x, dummy;
383
384                   umul_ppmm (x, dummy, ti, base_multiplier);
385                   quo = x >> brec->post_shift;
386                   rem = ti - quo * base;
387                   *--bp = digits[rem];
388                   ti = quo;
389                   ++ndig_for_this_limb;
390                 }
391 #else
392             while (ti != 0)
393               {
394                 mp_limb quo, rem;
395
396                 quo = ti / base;
397                 rem = ti % base;
398                 *--bp = digits[rem];
399                 ti = quo;
400                 ++ndig_for_this_limb;
401               }
402 #endif
403             /* If this wasn't the most significant word, pad with zeros.  */
404             if (n != 0)
405               while (ndig_for_this_limb < brec->big.ndigits)
406                 {
407                   *--bp = '0';
408                   ++ndig_for_this_limb;
409                 }
410           }
411         while (n != 0);
412 #endif
413       }
414       break;
415     }
416
417   return bp;
418 }