1/* Internal function for converting integers to ASCII.
2 Copyright (C) 1994-2024 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19/* Mark symbols hidden in static PIE for early self relocation to work.
20 Note: string.h may have ifuncs which cannot be hidden on i686. */
21#if BUILD_PIE_DEFAULT
22# pragma GCC visibility push(hidden)
23#endif
24#include <gmp-mparam.h>
25#include <gmp.h>
26#include <limits.h>
27#include <stdlib/gmp-impl.h>
28#include <stdlib/longlong.h>
29
30#include <_itoa.h>
31
32
33/* Canonize environment. For some architectures not all values might
34 be defined in the GMP header files. */
35#ifndef UMUL_TIME
36# define UMUL_TIME 1
37#endif
38#ifndef UDIV_TIME
39# define UDIV_TIME 3
40#endif
41
42/* Control memory layout. */
43#ifdef PACK
44# undef PACK
45# define PACK __attribute__ ((packed))
46#else
47# define PACK
48#endif
49
50
51/* Declare local types. */
52struct base_table_t
53{
54#if (UDIV_TIME > 2 * UMUL_TIME)
55 mp_limb_t base_multiplier;
56#endif
57 char flag;
58 char post_shift;
59#if BITS_PER_MP_LIMB == 32
60 struct
61 {
62 char normalization_steps;
63 char ndigits;
64 mp_limb_t base PACK;
65#if UDIV_TIME > 2 * UMUL_TIME
66 mp_limb_t base_ninv PACK;
67#endif
68 } big;
69#endif
70};
71
72/* To reduce the memory needed we include some fields of the tables
73 only conditionally. */
74#if UDIV_TIME > 2 * UMUL_TIME
75# define SEL1(X) X,
76# define SEL2(X) ,X
77#else
78# define SEL1(X)
79# define SEL2(X)
80#endif
81
82
83/* We do not compile _itoa if we always can use _itoa_word. */
84#if _ITOA_NEEDED
85/* Local variables. */
86const struct base_table_t _itoa_base_table[] attribute_hidden =
87{
88# if BITS_PER_MP_LIMB == 64
89 /* 2 */ {SEL1(0ull) 1, 1},
90 /* 3 */ {SEL1(0xaaaaaaaaaaaaaaabull) 0, 1},
91 /* 4 */ {SEL1(0ull) 1, 2},
92 /* 5 */ {SEL1(0xcccccccccccccccdull) 0, 2},
93 /* 6 */ {SEL1(0xaaaaaaaaaaaaaaabull) 0, 2},
94 /* 7 */ {SEL1(0x2492492492492493ull) 1, 3},
95 /* 8 */ {SEL1(0ull) 1, 3},
96 /* 9 */ {SEL1(0xe38e38e38e38e38full) 0, 3},
97 /* 10 */ {SEL1(0xcccccccccccccccdull) 0, 3},
98 /* 11 */ {SEL1(0x2e8ba2e8ba2e8ba3ull) 0, 1},
99 /* 12 */ {SEL1(0xaaaaaaaaaaaaaaabull) 0, 3},
100 /* 13 */ {SEL1(0x4ec4ec4ec4ec4ec5ull) 0, 2},
101 /* 14 */ {SEL1(0x2492492492492493ull) 1, 4},
102 /* 15 */ {SEL1(0x8888888888888889ull) 0, 3},
103 /* 16 */ {SEL1(0ull) 1, 4},
104 /* 17 */ {SEL1(0xf0f0f0f0f0f0f0f1ull) 0, 4},
105 /* 18 */ {SEL1(0xe38e38e38e38e38full) 0, 4},
106 /* 19 */ {SEL1(0xd79435e50d79435full) 0, 4},
107 /* 20 */ {SEL1(0xcccccccccccccccdull) 0, 4},
108 /* 21 */ {SEL1(0x8618618618618619ull) 1, 5},
109 /* 22 */ {SEL1(0x2e8ba2e8ba2e8ba3ull) 0, 2},
110 /* 23 */ {SEL1(0x642c8590b21642c9ull) 1, 5},
111 /* 24 */ {SEL1(0xaaaaaaaaaaaaaaabull) 0, 4},
112 /* 25 */ {SEL1(0x47ae147ae147ae15ull) 1, 5},
113 /* 26 */ {SEL1(0x4ec4ec4ec4ec4ec5ull) 0, 3},
114 /* 27 */ {SEL1(0x97b425ed097b425full) 0, 4},
115 /* 28 */ {SEL1(0x2492492492492493ull) 1, 5},
116 /* 29 */ {SEL1(0x1a7b9611a7b9611bull) 1, 5},
117 /* 30 */ {SEL1(0x8888888888888889ull) 0, 4},
118 /* 31 */ {SEL1(0x0842108421084211ull) 1, 5},
119 /* 32 */ {SEL1(0ull) 1, 5},
120 /* 33 */ {SEL1(0x0f83e0f83e0f83e1ull) 0, 1},
121 /* 34 */ {SEL1(0xf0f0f0f0f0f0f0f1ull) 0, 5},
122 /* 35 */ {SEL1(0xea0ea0ea0ea0ea0full) 0, 5},
123 /* 36 */ {SEL1(0xe38e38e38e38e38full) 0, 5}
124# endif
125# if BITS_PER_MP_LIMB == 32
126 /* 2 */ {SEL1(0ul) 1, 1, {0, 31, 0x80000000ul SEL2(0xfffffffful)}},
127 /* 3 */ {SEL1(0xaaaaaaabul) 0, 1, {0, 20, 0xcfd41b91ul SEL2(0x3b563c24ul)}},
128 /* 4 */ {SEL1(0ul) 1, 2, {1, 15, 0x40000000ul SEL2(0xfffffffful)}},
129 /* 5 */ {SEL1(0xcccccccdul) 0, 2, {1, 13, 0x48c27395ul SEL2(0xc25c2684ul)}},
130 /* 6 */ {SEL1(0xaaaaaaabul) 0, 2, {0, 12, 0x81bf1000ul SEL2(0xf91bd1b6ul)}},
131 /* 7 */ {SEL1(0x24924925ul) 1, 3, {1, 11, 0x75db9c97ul SEL2(0x1607a2cbul)}},
132 /* 8 */ {SEL1(0ul) 1, 3, {1, 10, 0x40000000ul SEL2(0xfffffffful)}},
133 /* 9 */ {SEL1(0x38e38e39ul) 0, 1, {0, 10, 0xcfd41b91ul SEL2(0x3b563c24ul)}},
134 /* 10 */ {SEL1(0xcccccccdul) 0, 3, {2, 9, 0x3b9aca00ul SEL2(0x12e0be82ul)}},
135 /* 11 */ {SEL1(0xba2e8ba3ul) 0, 3, {0, 9, 0x8c8b6d2bul SEL2(0xd24cde04ul)}},
136 /* 12 */ {SEL1(0xaaaaaaabul) 0, 3, {3, 8, 0x19a10000ul SEL2(0x3fa39ab5ul)}},
137 /* 13 */ {SEL1(0x4ec4ec4ful) 0, 2, {2, 8, 0x309f1021ul SEL2(0x50f8ac5ful)}},
138 /* 14 */ {SEL1(0x24924925ul) 1, 4, {1, 8, 0x57f6c100ul SEL2(0x74843b1eul)}},
139 /* 15 */ {SEL1(0x88888889ul) 0, 3, {0, 8, 0x98c29b81ul SEL2(0xad0326c2ul)}},
140 /* 16 */ {SEL1(0ul) 1, 4, {3, 7, 0x10000000ul SEL2(0xfffffffful)}},
141 /* 17 */ {SEL1(0xf0f0f0f1ul) 0, 4, {3, 7, 0x18754571ul SEL2(0x4ef0b6bdul)}},
142 /* 18 */ {SEL1(0x38e38e39ul) 0, 2, {2, 7, 0x247dbc80ul SEL2(0xc0fc48a1ul)}},
143 /* 19 */ {SEL1(0xaf286bcbul) 1, 5, {2, 7, 0x3547667bul SEL2(0x33838942ul)}},
144 /* 20 */ {SEL1(0xcccccccdul) 0, 4, {1, 7, 0x4c4b4000ul SEL2(0xad7f29abul)}},
145 /* 21 */ {SEL1(0x86186187ul) 1, 5, {1, 7, 0x6b5a6e1dul SEL2(0x313c3d15ul)}},
146 /* 22 */ {SEL1(0xba2e8ba3ul) 0, 4, {0, 7, 0x94ace180ul SEL2(0xb8cca9e0ul)}},
147 /* 23 */ {SEL1(0xb21642c9ul) 0, 4, {0, 7, 0xcaf18367ul SEL2(0x42ed6de9ul)}},
148 /* 24 */ {SEL1(0xaaaaaaabul) 0, 4, {4, 6, 0x0b640000ul SEL2(0x67980e0bul)}},
149 /* 25 */ {SEL1(0x51eb851ful) 0, 3, {4, 6, 0x0e8d4a51ul SEL2(0x19799812ul)}},
150 /* 26 */ {SEL1(0x4ec4ec4ful) 0, 3, {3, 6, 0x1269ae40ul SEL2(0xbce85396ul)}},
151 /* 27 */ {SEL1(0x2f684bdbul) 1, 5, {3, 6, 0x17179149ul SEL2(0x62c103a9ul)}},
152 /* 28 */ {SEL1(0x24924925ul) 1, 5, {3, 6, 0x1cb91000ul SEL2(0x1d353d43ul)}},
153 /* 29 */ {SEL1(0x8d3dcb09ul) 0, 4, {2, 6, 0x23744899ul SEL2(0xce1deceaul)}},
154 /* 30 */ {SEL1(0x88888889ul) 0, 4, {2, 6, 0x2b73a840ul SEL2(0x790fc511ul)}},
155 /* 31 */ {SEL1(0x08421085ul) 1, 5, {2, 6, 0x34e63b41ul SEL2(0x35b865a0ul)}},
156 /* 32 */ {SEL1(0ul) 1, 5, {1, 6, 0x40000000ul SEL2(0xfffffffful)}},
157 /* 33 */ {SEL1(0x3e0f83e1ul) 0, 3, {1, 6, 0x4cfa3cc1ul SEL2(0xa9aed1b3ul)}},
158 /* 34 */ {SEL1(0xf0f0f0f1ul) 0, 5, {1, 6, 0x5c13d840ul SEL2(0x63dfc229ul)}},
159 /* 35 */ {SEL1(0xd41d41d5ul) 1, 6, {1, 6, 0x6d91b519ul SEL2(0x2b0fee30ul)}},
160 /* 36 */ {SEL1(0x38e38e39ul) 0, 3, {0, 6, 0x81bf1000ul SEL2(0xf91bd1b6ul)}}
161# endif
162};
163#endif
164
165#if IS_IN (libc)
166char *
167_itoa_word (_ITOA_WORD_TYPE value, char *buflim,
168 unsigned int base, int upper_case)
169{
170 const char *digits = (upper_case
171 ? _itoa_upper_digits
172 : _itoa_lower_digits);
173
174 switch (base)
175 {
176#define SPECIAL(Base) \
177 case Base: \
178 do \
179 *--buflim = digits[value % Base]; \
180 while ((value /= Base) != 0); \
181 break
182
183 SPECIAL (10);
184 SPECIAL (16);
185 SPECIAL (8);
186 default:
187 do
188 *--buflim = digits[value % base];
189 while ((value /= base) != 0);
190 }
191 return buflim;
192}
193#undef SPECIAL
194#endif /* IS_IN (libc) */
195
196
197#if _ITOA_NEEDED
198char *
199_itoa (unsigned long long int value, char *buflim, unsigned int base,
200 int upper_case)
201{
202 const char *digits = (upper_case
203 ? _itoa_upper_digits
204 : _itoa_lower_digits);
205 const struct base_table_t *brec = &_itoa_base_table[base - 2];
206
207 switch (base)
208 {
209# define RUN_2N(BITS) \
210 do \
211 { \
212 /* `unsigned long long int' always has 64 bits. */ \
213 mp_limb_t work_hi = value >> (64 - BITS_PER_MP_LIMB); \
214 \
215 if (BITS_PER_MP_LIMB == 32) \
216 { \
217 if (work_hi != 0) \
218 { \
219 mp_limb_t work_lo; \
220 int cnt; \
221 \
222 work_lo = value & 0xfffffffful; \
223 for (cnt = BITS_PER_MP_LIMB / BITS; cnt > 0; --cnt) \
224 { \
225 *--buflim = digits[work_lo & ((1ul << BITS) - 1)]; \
226 work_lo >>= BITS; \
227 } \
228 if (BITS_PER_MP_LIMB % BITS != 0) \
229 { \
230 work_lo \
231 |= ((work_hi \
232 & ((1 << (BITS - BITS_PER_MP_LIMB%BITS)) \
233 - 1)) \
234 << BITS_PER_MP_LIMB % BITS); \
235 work_hi >>= BITS - BITS_PER_MP_LIMB % BITS; \
236 if (work_hi == 0) \
237 work_hi = work_lo; \
238 else \
239 *--buflim = digits[work_lo]; \
240 } \
241 } \
242 else \
243 work_hi = value & 0xfffffffful; \
244 } \
245 do \
246 { \
247 *--buflim = digits[work_hi & ((1 << BITS) - 1)]; \
248 work_hi >>= BITS; \
249 } \
250 while (work_hi != 0); \
251 } \
252 while (0)
253 case 8:
254 RUN_2N (3);
255 break;
256
257 case 16:
258 RUN_2N (4);
259 break;
260
261 default:
262 {
263 char *bufend = buflim;
264# if BITS_PER_MP_LIMB == 64
265 mp_limb_t base_multiplier = brec->base_multiplier;
266 if (brec->flag)
267 while (value != 0)
268 {
269 mp_limb_t quo, rem, x;
270 mp_limb_t dummy __attribute__ ((unused));
271
272 umul_ppmm (x, dummy, value, base_multiplier);
273 quo = (x + ((value - x) >> 1)) >> (brec->post_shift - 1);
274 rem = value - quo * base;
275 *--buflim = digits[rem];
276 value = quo;
277 }
278 else
279 while (value != 0)
280 {
281 mp_limb_t quo, rem, x;
282 mp_limb_t dummy __attribute__ ((unused));
283
284 umul_ppmm (x, dummy, value, base_multiplier);
285 quo = x >> brec->post_shift;
286 rem = value - quo * base;
287 *--buflim = digits[rem];
288 value = quo;
289 }
290# endif
291# if BITS_PER_MP_LIMB == 32
292 mp_limb_t t[3];
293 int n;
294
295 /* First convert x0 to 1-3 words in base s->big.base.
296 Optimize for frequent cases of 32 bit numbers. */
297 if ((mp_limb_t) (value >> 32) >= 1)
298 {
299# if UDIV_TIME > 2 * UMUL_TIME || UDIV_NEEDS_NORMALIZATION
300 int big_normalization_steps = brec->big.normalization_steps;
301 mp_limb_t big_base_norm
302 = brec->big.base << big_normalization_steps;
303# endif
304 if ((mp_limb_t) (value >> 32) >= brec->big.base)
305 {
306 mp_limb_t x1hi, x1lo, r;
307 /* If you want to optimize this, take advantage of
308 that the quotient in the first udiv_qrnnd will
309 always be very small. It might be faster just to
310 subtract in a tight loop. */
311
312# if UDIV_TIME > 2 * UMUL_TIME
313 mp_limb_t x, xh, xl;
314
315 if (big_normalization_steps == 0)
316 xh = 0;
317 else
318 xh = (mp_limb_t) (value >> (64 - big_normalization_steps));
319 xl = (mp_limb_t) (value >> (32 - big_normalization_steps));
320 udiv_qrnnd_preinv (x1hi, r, xh, xl, big_base_norm,
321 brec->big.base_ninv);
322
323 xl = ((mp_limb_t) value) << big_normalization_steps;
324 udiv_qrnnd_preinv (x1lo, x, r, xl, big_base_norm,
325 brec->big.base_ninv);
326 t[2] = x >> big_normalization_steps;
327
328 if (big_normalization_steps == 0)
329 xh = x1hi;
330 else
331 xh = ((x1hi << big_normalization_steps)
332 | (x1lo >> (32 - big_normalization_steps)));
333 xl = x1lo << big_normalization_steps;
334 udiv_qrnnd_preinv (t[0], x, xh, xl, big_base_norm,
335 brec->big.base_ninv);
336 t[1] = x >> big_normalization_steps;
337# elif UDIV_NEEDS_NORMALIZATION
338 mp_limb_t x, xh, xl;
339
340 if (big_normalization_steps == 0)
341 xh = 0;
342 else
343 xh = (mp_limb_t) (value >> 64 - big_normalization_steps);
344 xl = (mp_limb_t) (value >> 32 - big_normalization_steps);
345 udiv_qrnnd (x1hi, r, xh, xl, big_base_norm);
346
347 xl = ((mp_limb_t) value) << big_normalization_steps;
348 udiv_qrnnd (x1lo, x, r, xl, big_base_norm);
349 t[2] = x >> big_normalization_steps;
350
351 if (big_normalization_steps == 0)
352 xh = x1hi;
353 else
354 xh = ((x1hi << big_normalization_steps)
355 | (x1lo >> 32 - big_normalization_steps));
356 xl = x1lo << big_normalization_steps;
357 udiv_qrnnd (t[0], x, xh, xl, big_base_norm);
358 t[1] = x >> big_normalization_steps;
359# else
360 udiv_qrnnd (x1hi, r, 0, (mp_limb_t) (value >> 32),
361 brec->big.base);
362 udiv_qrnnd (x1lo, t[2], r, (mp_limb_t) value, brec->big.base);
363 udiv_qrnnd (t[0], t[1], x1hi, x1lo, brec->big.base);
364# endif
365 n = 3;
366 }
367 else
368 {
369# if UDIV_TIME > 2 * UMUL_TIME
370 mp_limb_t x;
371
372 value <<= brec->big.normalization_steps;
373 udiv_qrnnd_preinv (t[0], x, (mp_limb_t) (value >> 32),
374 (mp_limb_t) value, big_base_norm,
375 brec->big.base_ninv);
376 t[1] = x >> brec->big.normalization_steps;
377# elif UDIV_NEEDS_NORMALIZATION
378 mp_limb_t x;
379
380 value <<= big_normalization_steps;
381 udiv_qrnnd (t[0], x, (mp_limb_t) (value >> 32),
382 (mp_limb_t) value, big_base_norm);
383 t[1] = x >> big_normalization_steps;
384# else
385 udiv_qrnnd (t[0], t[1], (mp_limb_t) (value >> 32),
386 (mp_limb_t) value, brec->big.base);
387# endif
388 n = 2;
389 }
390 }
391 else
392 {
393 t[0] = value;
394 n = 1;
395 }
396
397 /* Convert the 1-3 words in t[], word by word, to ASCII. */
398 do
399 {
400 mp_limb_t ti = t[--n];
401 int ndig_for_this_limb = 0;
402
403# if UDIV_TIME > 2 * UMUL_TIME
404 mp_limb_t base_multiplier = brec->base_multiplier;
405 if (brec->flag)
406 while (ti != 0)
407 {
408 mp_limb_t quo, rem, x;
409 mp_limb_t dummy __attribute__ ((unused));
410
411 umul_ppmm (x, dummy, ti, base_multiplier);
412 quo = (x + ((ti - x) >> 1)) >> (brec->post_shift - 1);
413 rem = ti - quo * base;
414 *--buflim = digits[rem];
415 ti = quo;
416 ++ndig_for_this_limb;
417 }
418 else
419 while (ti != 0)
420 {
421 mp_limb_t quo, rem, x;
422 mp_limb_t dummy __attribute__ ((unused));
423
424 umul_ppmm (x, dummy, ti, base_multiplier);
425 quo = x >> brec->post_shift;
426 rem = ti - quo * base;
427 *--buflim = digits[rem];
428 ti = quo;
429 ++ndig_for_this_limb;
430 }
431# else
432 while (ti != 0)
433 {
434 mp_limb_t quo, rem;
435
436 quo = ti / base;
437 rem = ti % base;
438 *--buflim = digits[rem];
439 ti = quo;
440 ++ndig_for_this_limb;
441 }
442# endif
443 /* If this wasn't the most significant word, pad with zeros. */
444 if (n != 0)
445 while (ndig_for_this_limb < brec->big.ndigits)
446 {
447 *--buflim = '0';
448 ++ndig_for_this_limb;
449 }
450 }
451 while (n != 0);
452# endif
453 if (buflim == bufend)
454 *--buflim = '0';
455 }
456 break;
457 }
458
459 return buflim;
460}
461#endif
462
463char *
464_fitoa_word (_ITOA_WORD_TYPE value, char *buf, unsigned int base,
465 int upper_case)
466{
467 char tmpbuf[sizeof (value) * 4]; /* Worst case length: base 2. */
468 char *cp = _itoa_word (value, buflim: tmpbuf + sizeof (value) * 4, base, upper_case);
469 while (cp < tmpbuf + sizeof (value) * 4)
470 *buf++ = *cp++;
471 return buf;
472}
473
474#if _ITOA_NEEDED
475char *
476_fitoa (unsigned long long value, char *buf, unsigned int base, int upper_case)
477{
478 char tmpbuf[sizeof (value) * 4]; /* Worst case length: base 2. */
479 char *cp = _itoa (value, tmpbuf + sizeof (value) * 4, base, upper_case);
480 while (cp < tmpbuf + sizeof (value) * 4)
481 *buf++ = *cp++;
482 return buf;
483}
484#endif
485

source code of glibc/stdio-common/_itoa.c