diff options
Diffstat (limited to 'stdio-common/_itowa.c')
| -rw-r--r-- | stdio-common/_itowa.c | 346 |
1 files changed, 346 insertions, 0 deletions
diff --git a/stdio-common/_itowa.c b/stdio-common/_itowa.c new file mode 100644 index 0000000000..430415b96b --- /dev/null +++ b/stdio-common/_itowa.c @@ -0,0 +1,346 @@ +/* Internal function for converting integers to ASCII. + Copyright (C) 1994, 1995, 1996, 1999 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Torbjorn Granlund <tege@matematik.su.se> + and Ulrich Drepper <drepper@gnu.org>. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include <gmp-mparam.h> +#include <stdlib/gmp.h> +#include <stdlib/gmp-impl.h> +#include <stdlib/longlong.h> + +#include "_itowa.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 + +/* Factor table for the different bases. */ +extern const struct base_table_t _itoa_base_table[]; + +/* Lower-case digits. */ +extern const wchar_t _itowa_lower_digits[]; +/* Upper-case digits. */ +extern const wchar_t _itowa_upper_digits[]; + + +wchar_t * +_itowa (value, buflim, base, upper_case) + unsigned long long int value; + wchar_t *buflim; + unsigned int base; + int upper_case; +{ + const wchar_t *digits = (upper_case + ? _itowa_upper_digits : _itowa_lower_digits); + wchar_t *bp = buflim; + 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) \ + { \ + *--bp = 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 \ + *--bp = digits[work_lo]; \ + } \ + } \ + else \ + work_hi = value & 0xfffffffful; \ + } \ + do \ + { \ + *--bp = 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: + { +#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, dummy; + + umul_ppmm (x, dummy, value, base_multiplier); + quo = (x + ((value - x) >> 1)) >> (brec->post_shift - 1); + rem = value - quo * base; + *--bp = digits[rem]; + value = quo; + } + else + while (value != 0) + { + mp_limb_t quo, rem, x, dummy; + + umul_ppmm (x, dummy, value, base_multiplier); + quo = x >> brec->post_shift; + rem = value - quo * base; + *--bp = 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, dummy; + + umul_ppmm (x, dummy, ti, base_multiplier); + quo = (x + ((ti - x) >> 1)) >> (brec->post_shift - 1); + rem = ti - quo * base; + *--bp = digits[rem]; + ti = quo; + ++ndig_for_this_limb; + } + else + while (ti != 0) + { + mp_limb_t quo, rem, x, dummy; + + umul_ppmm (x, dummy, ti, base_multiplier); + quo = x >> brec->post_shift; + rem = ti - quo * base; + *--bp = digits[rem]; + ti = quo; + ++ndig_for_this_limb; + } +#else + while (ti != 0) + { + mp_limb_t quo, rem; + + quo = ti / base; + rem = ti % base; + *--bp = 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) + { + *--bp = '0'; + ++ndig_for_this_limb; + } + } + while (n != 0); +#endif + } + break; + } + + return bp; +} |