aboutsummaryrefslogtreecommitdiff
path: root/stdio-common/_itoa.c
blob: 27285193bc8666c0de5b88e921e2060d624307ef (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
/* Internal function for converting integers to ASCII.
   Copyright (C) 1994-2023 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <https://www.gnu.org/licenses/>.  */

#include <gmp-mparam.h>
#include <gmp.h>
#include <limits.h>
#include <stdlib/gmp-impl.h>
#include <stdlib/longlong.h>

#include <_itoa.h>


/* Canonize environment.  For some architectures not all values might
   be defined in the GMP header files.  */
#ifndef UMUL_TIME
# define UMUL_TIME 1
#endif
#ifndef UDIV_TIME
# define UDIV_TIME 3
#endif

/* Control memory layout.  */
#ifdef PACK
# undef PACK
# define PACK __attribute__ ((packed))
#else
# define PACK
#endif


/* Declare local types.  */
struct base_table_t
{
#if (UDIV_TIME > 2 * UMUL_TIME)
  mp_limb_t base_multiplier;
#endif
  char flag;
  char post_shift;
#if BITS_PER_MP_LIMB == 32
  struct
    {
      char normalization_steps;
      char ndigits;
      mp_limb_t base PACK;
#if UDIV_TIME > 2 * UMUL_TIME
      mp_limb_t base_ninv PACK;
#endif
    } big;
#endif
};

/* To reduce the memory needed we include some fields of the tables
   only conditionally.  */
#if UDIV_TIME > 2 * UMUL_TIME
# define SEL1(X) X,
# define SEL2(X) ,X
#else
# define SEL1(X)
# define SEL2(X)
#endif


/* We do not compile _itoa if we always can use _itoa_word.  */
#if _ITOA_NEEDED
/* Local variables.  */
const struct base_table_t _itoa_base_table[] attribute_hidden =
{
# if BITS_PER_MP_LIMB == 64
  /*  2 */ {SEL1(0ull) 1, 1},
  /*  3 */ {SEL1(0xaaaaaaaaaaaaaaabull) 0, 1},
  /*  4 */ {SEL1(0ull) 1, 2},
  /*  5 */ {SEL1(0xcccccccccccccccdull) 0, 2},
  /*  6 */ {SEL1(0xaaaaaaaaaaaaaaabull) 0, 2},
  /*  7 */ {SEL1(0x2492492492492493ull) 1, 3},
  /*  8 */ {SEL1(0ull) 1, 3},
  /*  9 */ {SEL1(0xe38e38e38e38e38full) 0, 3},
  /* 10 */ {SEL1(0xcccccccccccccccdull) 0, 3},
  /* 11 */ {SEL1(0x2e8ba2e8ba2e8ba3ull) 0, 1},
  /* 12 */ {SEL1(0xaaaaaaaaaaaaaaabull) 0, 3},
  /* 13 */ {SEL1(0x4ec4ec4ec4ec4ec5ull) 0, 2},
  /* 14 */ {SEL1(0x2492492492492493ull) 1, 4},
  /* 15 */ {SEL1(0x8888888888888889ull) 0, 3},
  /* 16 */ {SEL1(0ull) 1, 4},
  /* 17 */ {SEL1(0xf0f0f0f0f0f0f0f1ull) 0, 4},
  /* 18 */ {SEL1(0xe38e38e38e38e38full) 0, 4},
  /* 19 */ {SEL1(0xd79435e50d79435full) 0, 4},
  /* 20 */ {SEL1(0xcccccccccccccccdull) 0, 4},
  /* 21 */ {SEL1(0x8618618618618619ull) 1, 5},
  /* 22 */ {SEL1(0x2e8ba2e8ba2e8ba3ull) 0, 2},
  /* 23 */ {SEL1(0x642c8590b21642c9ull) 1, 5},
  /* 24 */ {SEL1(0xaaaaaaaaaaaaaaabull) 0, 4},
  /* 25 */ {SEL1(0x47ae147ae147ae15ull) 1, 5},
  /* 26 */ {SEL1(0x4ec4ec4ec4ec4ec5ull) 0, 3},
  /* 27 */ {SEL1(0x97b425ed097b425full) 0, 4},
  /* 28 */ {SEL1(0x2492492492492493ull) 1, 5},
  /* 29 */ {SEL1(0x1a7b9611a7b9611bull) 1, 5},
  /* 30 */ {SEL1(0x8888888888888889ull) 0, 4},
  /* 31 */ {SEL1(0x0842108421084211ull) 1, 5},
  /* 32 */ {SEL1(0ull) 1, 5},
  /* 33 */ {SEL1(0x0f83e0f83e0f83e1ull) 0, 1},
  /* 34 */ {SEL1(0xf0f0f0f0f0f0f0f1ull) 0, 5},
  /* 35 */ {SEL1(0xea0ea0ea0ea0ea0full) 0, 5},
  /* 36 */ {SEL1(0xe38e38e38e38e38full) 0, 5}
# endif
# if BITS_PER_MP_LIMB == 32
  /*  2 */ {SEL1(0ul) 1, 1, {0, 31, 0x80000000ul SEL2(0xfffffffful)}},
  /*  3 */ {SEL1(0xaaaaaaabul) 0, 1, {0, 20, 0xcfd41b91ul SEL2(0x3b563c24ul)}},
  /*  4 */ {SEL1(0ul) 1, 2, {1, 15, 0x40000000ul SEL2(0xfffffffful)}},
  /*  5 */ {SEL1(0xcccccccdul) 0, 2, {1, 13, 0x48c27395ul SEL2(0xc25c2684ul)}},
  /*  6 */ {SEL1(0xaaaaaaabul) 0, 2, {0, 12, 0x81bf1000ul SEL2(0xf91bd1b6ul)}},
  /*  7 */ {SEL1(0x24924925ul) 1, 3, {1, 11, 0x75db9c97ul SEL2(0x1607a2cbul)}},
  /*  8 */ {SEL1(0ul) 1, 3, {1, 10, 0x40000000ul SEL2(0xfffffffful)}},
  /*  9 */ {SEL1(0x38e38e39ul) 0, 1, {0, 10, 0xcfd41b91ul SEL2(0x3b563c24ul)}},
  /* 10 */ {SEL1(0xcccccccdul) 0, 3, {2, 9, 0x3b9aca00ul SEL2(0x12e0be82ul)}},
  /* 11 */ {SEL1(0xba2e8ba3ul) 0, 3, {0, 9, 0x8c8b6d2bul SEL2(0xd24cde04ul)}},
  /* 12 */ {SEL1(0xaaaaaaabul) 0, 3, {3, 8, 0x19a10000ul SEL2(0x3fa39ab5ul)}},
  /* 13 */ {SEL1(0x4ec4ec4ful) 0, 2, {2, 8, 0x309f1021ul SEL2(0x50f8ac5ful)}},
  /* 14 */ {SEL1(0x24924925ul) 1, 4, {1, 8, 0x57f6c100ul SEL2(0x74843b1eul)}},
  /* 15 */ {SEL1(0x88888889ul) 0, 3, {0, 8, 0x98c29b81ul SEL2(0xad0326c2ul)}},
  /* 16 */ {SEL1(0ul) 1, 4, {3, 7, 0x10000000ul SEL2(0xfffffffful)}},
  /* 17 */ {SEL1(0xf0f0f0f1ul) 0, 4, {3, 7, 0x18754571ul SEL2(0x4ef0b6bdul)}},
  /* 18 */ {SEL1(0x38e38e39ul) 0, 2, {2, 7, 0x247dbc80ul SEL2(0xc0fc48a1ul)}},
  /* 19 */ {SEL1(0xaf286bcbul) 1, 5, {2, 7, 0x3547667bul SEL2(0x33838942ul)}},
  /* 20 */ {SEL1(0xcccccccdul) 0, 4, {1, 7, 0x4c4b4000ul SEL2(0xad7f29abul)}},
  /* 21 */ {SEL1(0x86186187ul) 1, 5, {1, 7, 0x6b5a6e1dul SEL2(0x313c3d15ul)}},
  /* 22 */ {SEL1(0xba2e8ba3ul) 0, 4, {0, 7, 0x94ace180ul SEL2(0xb8cca9e0ul)}},
  /* 23 */ {SEL1(0xb21642c9ul) 0, 4, {0, 7, 0xcaf18367ul SEL2(0x42ed6de9ul)}},
  /* 24 */ {SEL1(0xaaaaaaabul) 0, 4, {4, 6, 0x0b640000ul SEL2(0x67980e0bul)}},
  /* 25 */ {SEL1(0x51eb851ful) 0, 3, {4, 6, 0x0e8d4a51ul SEL2(0x19799812ul)}},
  /* 26 */ {SEL1(0x4ec4ec4ful) 0, 3, {3, 6, 0x1269ae40ul SEL2(0xbce85396ul)}},
  /* 27 */ {SEL1(0x2f684bdbul) 1, 5, {3, 6, 0x17179149ul SEL2(0x62c103a9ul)}},
  /* 28 */ {SEL1(0x24924925ul) 1, 5, {3, 6, 0x1cb91000ul SEL2(0x1d353d43ul)}},
  /* 29 */ {SEL1(0x8d3dcb09ul) 0, 4, {2, 6, 0x23744899ul SEL2(0xce1deceaul)}},
  /* 30 */ {SEL1(0x88888889ul) 0, 4, {2, 6, 0x2b73a840ul SEL2(0x790fc511ul)}},
  /* 31 */ {SEL1(0x08421085ul) 1, 5, {2, 6, 0x34e63b41ul SEL2(0x35b865a0ul)}},
  /* 32 */ {SEL1(0ul) 1, 5, {1, 6, 0x40000000ul SEL2(0xfffffffful)}},
  /* 33 */ {SEL1(0x3e0f83e1ul) 0, 3, {1, 6, 0x4cfa3cc1ul SEL2(0xa9aed1b3ul)}},
  /* 34 */ {SEL1(0xf0f0f0f1ul) 0, 5, {1, 6, 0x5c13d840ul SEL2(0x63dfc229ul)}},
  /* 35 */ {SEL1(0xd41d41d5ul) 1, 6, {1, 6, 0x6d91b519ul SEL2(0x2b0fee30ul)}},
  /* 36 */ {SEL1(0x38e38e39ul) 0, 3, {0, 6, 0x81bf1000ul SEL2(0xf91bd1b6ul)}}
# endif
};
#endif

char *
_itoa_word (_ITOA_WORD_TYPE value, char *buflim,
	    unsigned int base, int upper_case)
{
  const char *digits = (upper_case
			? _itoa_upper_digits
			: _itoa_lower_digits);

  switch (base)
    {
#define SPECIAL(Base)							      \
    case Base:								      \
      do								      \
	*--buflim = digits[value % Base];				      \
      while ((value /= Base) != 0);					      \
      break

      SPECIAL (10);
      SPECIAL (16);
      SPECIAL (8);
    default:
      do
	*--buflim = digits[value % base];
      while ((value /= base) != 0);
    }
  return buflim;
}
#undef SPECIAL


#if _ITOA_NEEDED
char *
_itoa (unsigned long long int value, char *buflim, unsigned int base,
       int upper_case)
{
  const char *digits = (upper_case
			? _itoa_upper_digits
			: _itoa_lower_digits);
  const struct base_table_t *brec = &_itoa_base_table[base - 2];

  switch (base)
    {
# define RUN_2N(BITS) \
      do								      \
	{								      \
	  /* `unsigned long long int' always has 64 bits.  */		      \
	  mp_limb_t work_hi = value >> (64 - BITS_PER_MP_LIMB);		      \
									      \
	  if (BITS_PER_MP_LIMB == 32)					      \
	    {								      \
	      if (work_hi != 0)						      \
		{							      \
		  mp_limb_t work_lo;					      \
		  int cnt;						      \
									      \
		  work_lo = value & 0xfffffffful;			      \
		  for (cnt = BITS_PER_MP_LIMB / BITS; cnt > 0; --cnt)	      \
		    {							      \
		      *--buflim = digits[work_lo & ((1ul << BITS) - 1)];      \
		      work_lo >>= BITS;					      \
		    }							      \
		  if (BITS_PER_MP_LIMB % BITS != 0)			      \
		    {							      \
		      work_lo						      \
			|= ((work_hi					      \
			     & ((1 << (BITS - BITS_PER_MP_LIMB%BITS))	      \
				- 1))					      \
			    << BITS_PER_MP_LIMB % BITS);		      \
		      work_hi >>= BITS - BITS_PER_MP_LIMB % BITS;	      \
		      if (work_hi == 0)					      \
			work_hi = work_lo;				      \
		      else						      \
			*--buflim = digits[work_lo];			      \
		    }							      \
		}							      \
	      else							      \
		work_hi = value & 0xfffffffful;				      \
	    }								      \
	  do								      \
	    {								      \
	      *--buflim = digits[work_hi & ((1 << BITS) - 1)];		      \
	      work_hi >>= BITS;						      \
	    }								      \
	  while (work_hi != 0);						      \
	}								      \
      while (0)
    case 8:
      RUN_2N (3);
      break;

    case 16:
      RUN_2N (4);
      break;

    default:
      {
	char *bufend = buflim;
# if BITS_PER_MP_LIMB == 64
	mp_limb_t base_multiplier = brec->base_multiplier;
	if (brec->flag)
	  while (value != 0)
	    {
	      mp_limb_t quo, rem, x;
	      mp_limb_t dummy __attribute__ ((unused));

	      umul_ppmm (x, dummy, value, base_multiplier);
	      quo = (x + ((value - x) >> 1)) >> (brec->post_shift - 1);
	      rem = value - quo * base;
	      *--buflim = digits[rem];
	      value = quo;
	    }
	else
	  while (value != 0)
	    {
	      mp_limb_t quo, rem, x;
	      mp_limb_t dummy __attribute__ ((unused));

	      umul_ppmm (x, dummy, value, base_multiplier);
	      quo = x >> brec->post_shift;
	      rem = value - quo * base;
	      *--buflim = digits[rem];
	      value = quo;
	    }
# endif
# if BITS_PER_MP_LIMB == 32
	mp_limb_t t[3];
	int n;

	/* First convert x0 to 1-3 words in base s->big.base.
	   Optimize for frequent cases of 32 bit numbers.  */
	if ((mp_limb_t) (value >> 32) >= 1)
	  {
#  if UDIV_TIME > 2 * UMUL_TIME || UDIV_NEEDS_NORMALIZATION
	    int big_normalization_steps = brec->big.normalization_steps;
	    mp_limb_t big_base_norm
	      = brec->big.base << big_normalization_steps;
#  endif
	    if ((mp_limb_t) (value >> 32) >= brec->big.base)
	      {
		mp_limb_t x1hi, x1lo, r;
		/* If you want to optimize this, take advantage of
		   that the quotient in the first udiv_qrnnd will
		   always be very small.  It might be faster just to
		   subtract in a tight loop.  */

#  if UDIV_TIME > 2 * UMUL_TIME
		mp_limb_t x, xh, xl;

		if (big_normalization_steps == 0)
		  xh = 0;
		else
		  xh = (mp_limb_t) (value >> (64 - big_normalization_steps));
		xl = (mp_limb_t) (value >> (32 - big_normalization_steps));
		udiv_qrnnd_preinv (x1hi, r, xh, xl, big_base_norm,
				   brec->big.base_ninv);

		xl = ((mp_limb_t) value) << big_normalization_steps;
		udiv_qrnnd_preinv (x1lo, x, r, xl, big_base_norm,
				   brec->big.base_ninv);
		t[2] = x >> big_normalization_steps;

		if (big_normalization_steps == 0)
		  xh = x1hi;
		else
		  xh = ((x1hi << big_normalization_steps)
			| (x1lo >> (32 - big_normalization_steps)));
		xl = x1lo << big_normalization_steps;
		udiv_qrnnd_preinv (t[0], x, xh, xl, big_base_norm,
				   brec->big.base_ninv);
		t[1] = x >> big_normalization_steps;
#  elif UDIV_NEEDS_NORMALIZATION
		mp_limb_t x, xh, xl;

		if (big_normalization_steps == 0)
		  xh = 0;
		else
		  xh = (mp_limb_t) (value >> 64 - big_normalization_steps);
		xl = (mp_limb_t) (value >> 32 - big_normalization_steps);
		udiv_qrnnd (x1hi, r, xh, xl, big_base_norm);

		xl = ((mp_limb_t) value) << big_normalization_steps;
		udiv_qrnnd (x1lo, x, r, xl, big_base_norm);
		t[2] = x >> big_normalization_steps;

		if (big_normalization_steps == 0)
		  xh = x1hi;
		else
		  xh = ((x1hi << big_normalization_steps)
			| (x1lo >> 32 - big_normalization_steps));
		xl = x1lo << big_normalization_steps;
		udiv_qrnnd (t[0], x, xh, xl, big_base_norm);
		t[1] = x >> big_normalization_steps;
#  else
		udiv_qrnnd (x1hi, r, 0, (mp_limb_t) (value >> 32),
			    brec->big.base);
		udiv_qrnnd (x1lo, t[2], r, (mp_limb_t) value, brec->big.base);
		udiv_qrnnd (t[0], t[1], x1hi, x1lo, brec->big.base);
#  endif
		n = 3;
	      }
	    else
	      {
#  if UDIV_TIME > 2 * UMUL_TIME
		mp_limb_t x;

		value <<= brec->big.normalization_steps;
		udiv_qrnnd_preinv (t[0], x, (mp_limb_t) (value >> 32),
				   (mp_limb_t) value, big_base_norm,
				   brec->big.base_ninv);
		t[1] = x >> brec->big.normalization_steps;
#  elif UDIV_NEEDS_NORMALIZATION
		mp_limb_t x;

		value <<= big_normalization_steps;
		udiv_qrnnd (t[0], x, (mp_limb_t) (value >> 32),
			    (mp_limb_t) value, big_base_norm);
		t[1] = x >> big_normalization_steps;
#  else
		udiv_qrnnd (t[0], t[1], (mp_limb_t) (value >> 32),
			    (mp_limb_t) value, brec->big.base);
#  endif
		n = 2;
	      }
	  }
	else
	  {
	    t[0] = value;
	    n = 1;
	  }

	/* Convert the 1-3 words in t[], word by word, to ASCII.  */
	do
	  {
	    mp_limb_t ti = t[--n];
	    int ndig_for_this_limb = 0;

#  if UDIV_TIME > 2 * UMUL_TIME
	    mp_limb_t base_multiplier = brec->base_multiplier;
	    if (brec->flag)
	      while (ti != 0)
		{
		  mp_limb_t quo, rem, x;
		  mp_limb_t dummy __attribute__ ((unused));

		  umul_ppmm (x, dummy, ti, base_multiplier);
		  quo = (x + ((ti - x) >> 1)) >> (brec->post_shift - 1);
		  rem = ti - quo * base;
		  *--buflim = digits[rem];
		  ti = quo;
		  ++ndig_for_this_limb;
		}
	    else
	      while (ti != 0)
		{
		  mp_limb_t quo, rem, x;
		  mp_limb_t dummy __attribute__ ((unused));

		  umul_ppmm (x, dummy, ti, base_multiplier);
		  quo = x >> brec->post_shift;
		  rem = ti - quo * base;
		  *--buflim = digits[rem];
		  ti = quo;
		  ++ndig_for_this_limb;
		}
#  else
	    while (ti != 0)
	      {
		mp_limb_t quo, rem;

		quo = ti / base;
		rem = ti % base;
		*--buflim = digits[rem];
		ti = quo;
		++ndig_for_this_limb;
	      }
#  endif
	    /* If this wasn't the most significant word, pad with zeros.  */
	    if (n != 0)
	      while (ndig_for_this_limb < brec->big.ndigits)
		{
		  *--buflim = '0';
		  ++ndig_for_this_limb;
		}
	  }
	while (n != 0);
# endif
	if (buflim == bufend)
	  *--buflim = '0';
      }
      break;
    }

  return buflim;
}
#endif

char *
_fitoa_word (_ITOA_WORD_TYPE value, char *buf, unsigned int base,
	     int upper_case)
{
  char tmpbuf[sizeof (value) * 4];	      /* Worst case length: base 2.  */
  char *cp = _itoa_word (value, tmpbuf + sizeof (value) * 4, base, upper_case);
  while (cp < tmpbuf + sizeof (value) * 4)
    *buf++ = *cp++;
  return buf;
}

#if _ITOA_NEEDED
char *
_fitoa (unsigned long long value, char *buf, unsigned int base, int upper_case)
{
  char tmpbuf[sizeof (value) * 4];	      /* Worst case length: base 2.  */
  char *cp = _itoa (value, tmpbuf + sizeof (value) * 4, base, upper_case);
  while (cp < tmpbuf + sizeof (value) * 4)
    *buf++ = *cp++;
  return buf;
}
#endif