1577 lines
43 KiB
C
1577 lines
43 KiB
C
/* Convert string representing a number to float value, using given locale.
|
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Copyright (C) 1997,98,2002,2004,2005 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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||
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The GNU C Library is distributed in the hope that it will be useful,
|
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but WITHOUT ANY WARRANTY; without even the implied warranty of
|
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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||
Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, write to the Free
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Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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02111-1307 USA. */
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#include <xlocale.h>
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extern double ____strtod_l_internal (const char *, char **, int, __locale_t);
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extern unsigned long long int ____strtoull_l_internal (const char *, char **,
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int, int, __locale_t);
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/* Configuration part. These macros are defined by `strtold.c',
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`strtof.c', `wcstod.c', `wcstold.c', and `wcstof.c' to produce the
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`long double' and `float' versions of the reader. */
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#ifndef FLOAT
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# define FLOAT double
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# define FLT DBL
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# ifdef USE_WIDE_CHAR
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# define STRTOF wcstod_l
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# define __STRTOF __wcstod_l
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# else
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# define STRTOF strtod_l
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# define __STRTOF __strtod_l
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# endif
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# define MPN2FLOAT __mpn_construct_double
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# define FLOAT_HUGE_VAL HUGE_VAL
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# define SET_MANTISSA(flt, mant) \
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do { union ieee754_double u; \
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u.d = (flt); \
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if ((mant & 0xfffffffffffffULL) == 0) \
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mant = 0x8000000000000ULL; \
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u.ieee.mantissa0 = ((mant) >> 32) & 0xfffff; \
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u.ieee.mantissa1 = (mant) & 0xffffffff; \
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(flt) = u.d; \
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} while (0)
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#endif
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/* End of configuration part. */
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#include <ctype.h>
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#include <errno.h>
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#include <float.h>
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#include <ieee754.h>
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#include "../locale/localeinfo.h"
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#include <locale.h>
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#include <math.h>
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#include <stdlib.h>
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#include <string.h>
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/* The gmp headers need some configuration frobs. */
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#define HAVE_ALLOCA 1
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/* Include gmp-mparam.h first, such that definitions of _SHORT_LIMB
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and _LONG_LONG_LIMB in it can take effect into gmp.h. */
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#include <gmp-mparam.h>
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#include <gmp.h>
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#include "gmp-impl.h"
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#include "longlong.h"
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#include "fpioconst.h"
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#define NDEBUG 1
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#include <assert.h>
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/* We use this code for the extended locale handling where the
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function gets as an additional argument the locale which has to be
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used. To access the values we have to redefine the _NL_CURRENT and
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_NL_CURRENT_WORD macros. */
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#undef _NL_CURRENT
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#define _NL_CURRENT(category, item) \
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(current->values[_NL_ITEM_INDEX (item)].string)
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#undef _NL_CURRENT_WORD
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#define _NL_CURRENT_WORD(category, item) \
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((uint32_t) current->values[_NL_ITEM_INDEX (item)].word)
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#if defined _LIBC || defined HAVE_WCHAR_H
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# include <wchar.h>
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#endif
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#ifdef USE_WIDE_CHAR
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# include <wctype.h>
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# define STRING_TYPE wchar_t
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# define CHAR_TYPE wint_t
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# define L_(Ch) L##Ch
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# define ISSPACE(Ch) __iswspace_l ((Ch), loc)
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# define ISDIGIT(Ch) __iswdigit_l ((Ch), loc)
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# define ISXDIGIT(Ch) __iswxdigit_l ((Ch), loc)
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# define TOLOWER(Ch) __towlower_l ((Ch), loc)
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# define TOLOWER_C(Ch) __towlower_l ((Ch), _nl_C_locobj_ptr)
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# define STRNCASECMP(S1, S2, N) \
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__wcsncasecmp_l ((S1), (S2), (N), _nl_C_locobj_ptr)
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# define STRTOULL(S, E, B) ____wcstoull_l_internal ((S), (E), (B), 0, loc)
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#else
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# define STRING_TYPE char
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# define CHAR_TYPE char
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# define L_(Ch) Ch
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# define ISSPACE(Ch) __isspace_l ((Ch), loc)
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# define ISDIGIT(Ch) __isdigit_l ((Ch), loc)
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# define ISXDIGIT(Ch) __isxdigit_l ((Ch), loc)
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# define TOLOWER(Ch) __tolower_l ((Ch), loc)
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# define TOLOWER_C(Ch) __tolower_l ((Ch), _nl_C_locobj_ptr)
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# define STRNCASECMP(S1, S2, N) \
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__strncasecmp_l ((S1), (S2), (N), _nl_C_locobj_ptr)
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# define STRTOULL(S, E, B) ____strtoull_l_internal ((S), (E), (B), 0, loc)
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#endif
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/* Constants we need from float.h; select the set for the FLOAT precision. */
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#define MANT_DIG PASTE(FLT,_MANT_DIG)
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#define DIG PASTE(FLT,_DIG)
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#define MAX_EXP PASTE(FLT,_MAX_EXP)
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#define MIN_EXP PASTE(FLT,_MIN_EXP)
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#define MAX_10_EXP PASTE(FLT,_MAX_10_EXP)
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#define MIN_10_EXP PASTE(FLT,_MIN_10_EXP)
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/* Extra macros required to get FLT expanded before the pasting. */
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#define PASTE(a,b) PASTE1(a,b)
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#define PASTE1(a,b) a##b
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/* Function to construct a floating point number from an MP integer
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containing the fraction bits, a base 2 exponent, and a sign flag. */
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extern FLOAT MPN2FLOAT (mp_srcptr mpn, int exponent, int negative);
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/* Definitions according to limb size used. */
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#if BITS_PER_MP_LIMB == 32
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# define MAX_DIG_PER_LIMB 9
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# define MAX_FAC_PER_LIMB 1000000000UL
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#elif BITS_PER_MP_LIMB == 64
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# define MAX_DIG_PER_LIMB 19
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# define MAX_FAC_PER_LIMB 10000000000000000000ULL
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#else
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# error "mp_limb_t size " BITS_PER_MP_LIMB "not accounted for"
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#endif
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/* Local data structure. */
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static const mp_limb_t _tens_in_limb[MAX_DIG_PER_LIMB + 1] =
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{ 0, 10, 100,
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1000, 10000, 100000L,
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1000000L, 10000000L, 100000000L,
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1000000000L
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#if BITS_PER_MP_LIMB > 32
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, 10000000000ULL, 100000000000ULL,
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1000000000000ULL, 10000000000000ULL, 100000000000000ULL,
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1000000000000000ULL, 10000000000000000ULL, 100000000000000000ULL,
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1000000000000000000ULL, 10000000000000000000ULL
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#endif
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#if BITS_PER_MP_LIMB > 64
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#error "Need to expand tens_in_limb table to" MAX_DIG_PER_LIMB
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#endif
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};
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#ifndef howmany
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#define howmany(x,y) (((x)+((y)-1))/(y))
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#endif
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#define SWAP(x, y) ({ typeof(x) _tmp = x; x = y; y = _tmp; })
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#define NDIG (MAX_10_EXP - MIN_10_EXP + 2 * MANT_DIG)
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#define HEXNDIG ((MAX_EXP - MIN_EXP + 7) / 8 + 2 * MANT_DIG)
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#define RETURN_LIMB_SIZE howmany (MANT_DIG, BITS_PER_MP_LIMB)
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#define RETURN(val,end) \
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do { if (endptr != NULL) *endptr = (STRING_TYPE *) (end); \
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return val; } while (0)
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/* Maximum size necessary for mpn integers to hold floating point numbers. */
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#define MPNSIZE (howmany (MAX_EXP + 2 * MANT_DIG, BITS_PER_MP_LIMB) \
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+ 2)
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/* Declare an mpn integer variable that big. */
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#define MPN_VAR(name) mp_limb_t name[MPNSIZE]; mp_size_t name##size
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/* Copy an mpn integer value. */
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#define MPN_ASSIGN(dst, src) \
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memcpy (dst, src, (dst##size = src##size) * sizeof (mp_limb_t))
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/* Return a floating point number of the needed type according to the given
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multi-precision number after possible rounding. */
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static FLOAT
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round_and_return (mp_limb_t *retval, int exponent, int negative,
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mp_limb_t round_limb, mp_size_t round_bit, int more_bits)
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{
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if (exponent < MIN_EXP - 1)
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{
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mp_size_t shift = MIN_EXP - 1 - exponent;
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if (shift > MANT_DIG)
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{
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__set_errno (EDOM);
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return 0.0;
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}
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more_bits |= (round_limb & ((((mp_limb_t) 1) << round_bit) - 1)) != 0;
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if (shift == MANT_DIG)
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/* This is a special case to handle the very seldom case where
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the mantissa will be empty after the shift. */
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{
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int i;
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round_limb = retval[RETURN_LIMB_SIZE - 1];
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round_bit = (MANT_DIG - 1) % BITS_PER_MP_LIMB;
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for (i = 0; i < RETURN_LIMB_SIZE; ++i)
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more_bits |= retval[i] != 0;
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MPN_ZERO (retval, RETURN_LIMB_SIZE);
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}
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else if (shift >= BITS_PER_MP_LIMB)
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{
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int i;
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round_limb = retval[(shift - 1) / BITS_PER_MP_LIMB];
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round_bit = (shift - 1) % BITS_PER_MP_LIMB;
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for (i = 0; i < (shift - 1) / BITS_PER_MP_LIMB; ++i)
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more_bits |= retval[i] != 0;
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more_bits |= ((round_limb & ((((mp_limb_t) 1) << round_bit) - 1))
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!= 0);
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(void) __mpn_rshift (retval, &retval[shift / BITS_PER_MP_LIMB],
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RETURN_LIMB_SIZE - (shift / BITS_PER_MP_LIMB),
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shift % BITS_PER_MP_LIMB);
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MPN_ZERO (&retval[RETURN_LIMB_SIZE - (shift / BITS_PER_MP_LIMB)],
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shift / BITS_PER_MP_LIMB);
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}
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else if (shift > 0)
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{
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round_limb = retval[0];
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round_bit = shift - 1;
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(void) __mpn_rshift (retval, retval, RETURN_LIMB_SIZE, shift);
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}
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/* This is a hook for the m68k long double format, where the
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exponent bias is the same for normalized and denormalized
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numbers. */
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#ifndef DENORM_EXP
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# define DENORM_EXP (MIN_EXP - 2)
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#endif
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exponent = DENORM_EXP;
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}
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if ((round_limb & (((mp_limb_t) 1) << round_bit)) != 0
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&& (more_bits || (retval[0] & 1) != 0
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|| (round_limb & ((((mp_limb_t) 1) << round_bit) - 1)) != 0))
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{
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mp_limb_t cy = __mpn_add_1 (retval, retval, RETURN_LIMB_SIZE, 1);
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if (((MANT_DIG % BITS_PER_MP_LIMB) == 0 && cy) ||
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((MANT_DIG % BITS_PER_MP_LIMB) != 0 &&
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(retval[RETURN_LIMB_SIZE - 1]
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& (((mp_limb_t) 1) << (MANT_DIG % BITS_PER_MP_LIMB))) != 0))
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{
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++exponent;
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(void) __mpn_rshift (retval, retval, RETURN_LIMB_SIZE, 1);
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retval[RETURN_LIMB_SIZE - 1]
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|= ((mp_limb_t) 1) << ((MANT_DIG - 1) % BITS_PER_MP_LIMB);
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}
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else if (exponent == DENORM_EXP
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&& (retval[RETURN_LIMB_SIZE - 1]
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& (((mp_limb_t) 1) << ((MANT_DIG - 1) % BITS_PER_MP_LIMB)))
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!= 0)
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/* The number was denormalized but now normalized. */
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exponent = MIN_EXP - 1;
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}
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if (exponent > MAX_EXP)
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return negative ? -FLOAT_HUGE_VAL : FLOAT_HUGE_VAL;
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return MPN2FLOAT (retval, exponent, negative);
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}
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/* Read a multi-precision integer starting at STR with exactly DIGCNT digits
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into N. Return the size of the number limbs in NSIZE at the first
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character od the string that is not part of the integer as the function
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value. If the EXPONENT is small enough to be taken as an additional
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factor for the resulting number (see code) multiply by it. */
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static const STRING_TYPE *
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str_to_mpn (const STRING_TYPE *str, int digcnt, mp_limb_t *n, mp_size_t *nsize,
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int *exponent
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#ifndef USE_WIDE_CHAR
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, const char *decimal, size_t decimal_len, const char *thousands
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#endif
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)
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{
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/* Number of digits for actual limb. */
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int cnt = 0;
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mp_limb_t low = 0;
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mp_limb_t start;
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||
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*nsize = 0;
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assert (digcnt > 0);
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do
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{
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if (cnt == MAX_DIG_PER_LIMB)
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{
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if (*nsize == 0)
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{
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n[0] = low;
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*nsize = 1;
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}
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else
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{
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mp_limb_t cy;
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cy = __mpn_mul_1 (n, n, *nsize, MAX_FAC_PER_LIMB);
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cy += __mpn_add_1 (n, n, *nsize, low);
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if (cy != 0)
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{
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n[*nsize] = cy;
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++(*nsize);
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}
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}
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cnt = 0;
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low = 0;
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}
|
||
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/* There might be thousands separators or radix characters in
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the string. But these all can be ignored because we know the
|
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format of the number is correct and we have an exact number
|
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of characters to read. */
|
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#ifdef USE_WIDE_CHAR
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if (*str < L'0' || *str > L'9')
|
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++str;
|
||
#else
|
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if (*str < '0' || *str > '9')
|
||
{
|
||
int inner = 0;
|
||
if (thousands != NULL && *str == *thousands
|
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&& ({ for (inner = 1; thousands[inner] != '\0'; ++inner)
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if (thousands[inner] != str[inner])
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break;
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||
thousands[inner] == '\0'; }))
|
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str += inner;
|
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else
|
||
str += decimal_len;
|
||
}
|
||
#endif
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low = low * 10 + *str++ - L_('0');
|
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++cnt;
|
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}
|
||
while (--digcnt > 0);
|
||
|
||
if (*exponent > 0 && cnt + *exponent <= MAX_DIG_PER_LIMB)
|
||
{
|
||
low *= _tens_in_limb[*exponent];
|
||
start = _tens_in_limb[cnt + *exponent];
|
||
*exponent = 0;
|
||
}
|
||
else
|
||
start = _tens_in_limb[cnt];
|
||
|
||
if (*nsize == 0)
|
||
{
|
||
n[0] = low;
|
||
*nsize = 1;
|
||
}
|
||
else
|
||
{
|
||
mp_limb_t cy;
|
||
cy = __mpn_mul_1 (n, n, *nsize, start);
|
||
cy += __mpn_add_1 (n, n, *nsize, low);
|
||
if (cy != 0)
|
||
n[(*nsize)++] = cy;
|
||
}
|
||
|
||
return str;
|
||
}
|
||
|
||
|
||
/* Shift {PTR, SIZE} COUNT bits to the left, and fill the vacated bits
|
||
with the COUNT most significant bits of LIMB.
|
||
|
||
Tege doesn't like this function so I have to write it here myself. :)
|
||
--drepper */
|
||
static inline void
|
||
__attribute ((always_inline))
|
||
__mpn_lshift_1 (mp_limb_t *ptr, mp_size_t size, unsigned int count,
|
||
mp_limb_t limb)
|
||
{
|
||
if (__builtin_constant_p (count) && count == BITS_PER_MP_LIMB)
|
||
{
|
||
/* Optimize the case of shifting by exactly a word:
|
||
just copy words, with no actual bit-shifting. */
|
||
mp_size_t i;
|
||
for (i = size - 1; i > 0; --i)
|
||
ptr[i] = ptr[i - 1];
|
||
ptr[0] = limb;
|
||
}
|
||
else
|
||
{
|
||
(void) __mpn_lshift (ptr, ptr, size, count);
|
||
ptr[0] |= limb >> (BITS_PER_MP_LIMB - count);
|
||
}
|
||
}
|
||
|
||
|
||
#define INTERNAL(x) INTERNAL1(x)
|
||
#define INTERNAL1(x) __##x##_internal
|
||
|
||
/* This file defines a function to check for correct grouping. */
|
||
#include "grouping.h"
|
||
|
||
|
||
/* Return a floating point number with the value of the given string NPTR.
|
||
Set *ENDPTR to the character after the last used one. If the number is
|
||
smaller than the smallest representable number, set `errno' to ERANGE and
|
||
return 0.0. If the number is too big to be represented, set `errno' to
|
||
ERANGE and return HUGE_VAL with the appropriate sign. */
|
||
FLOAT
|
||
INTERNAL (__STRTOF) (nptr, endptr, group, loc)
|
||
const STRING_TYPE *nptr;
|
||
STRING_TYPE **endptr;
|
||
int group;
|
||
__locale_t loc;
|
||
{
|
||
int negative; /* The sign of the number. */
|
||
MPN_VAR (num); /* MP representation of the number. */
|
||
int exponent; /* Exponent of the number. */
|
||
|
||
/* Numbers starting `0X' or `0x' have to be processed with base 16. */
|
||
int base = 10;
|
||
|
||
/* When we have to compute fractional digits we form a fraction with a
|
||
second multi-precision number (and we sometimes need a second for
|
||
temporary results). */
|
||
MPN_VAR (den);
|
||
|
||
/* Representation for the return value. */
|
||
mp_limb_t retval[RETURN_LIMB_SIZE];
|
||
/* Number of bits currently in result value. */
|
||
int bits;
|
||
|
||
/* Running pointer after the last character processed in the string. */
|
||
const STRING_TYPE *cp, *tp;
|
||
/* Start of significant part of the number. */
|
||
const STRING_TYPE *startp, *start_of_digits;
|
||
/* Points at the character following the integer and fractional digits. */
|
||
const STRING_TYPE *expp;
|
||
/* Total number of digit and number of digits in integer part. */
|
||
int dig_no, int_no, lead_zero;
|
||
/* Contains the last character read. */
|
||
CHAR_TYPE c;
|
||
|
||
/* We should get wint_t from <stddef.h>, but not all GCC versions define it
|
||
there. So define it ourselves if it remains undefined. */
|
||
#ifndef _WINT_T
|
||
typedef unsigned int wint_t;
|
||
#endif
|
||
/* The radix character of the current locale. */
|
||
#ifdef USE_WIDE_CHAR
|
||
wchar_t decimal;
|
||
#else
|
||
const char *decimal;
|
||
size_t decimal_len;
|
||
#endif
|
||
/* The thousands character of the current locale. */
|
||
#ifdef USE_WIDE_CHAR
|
||
wchar_t thousands = L'\0';
|
||
#else
|
||
const char *thousands = NULL;
|
||
#endif
|
||
/* The numeric grouping specification of the current locale,
|
||
in the format described in <locale.h>. */
|
||
const char *grouping;
|
||
/* Used in several places. */
|
||
int cnt;
|
||
|
||
struct locale_data *current = loc->__locales[LC_NUMERIC];
|
||
|
||
if (group)
|
||
{
|
||
grouping = _NL_CURRENT (LC_NUMERIC, GROUPING);
|
||
if (*grouping <= 0 || *grouping == CHAR_MAX)
|
||
grouping = NULL;
|
||
else
|
||
{
|
||
/* Figure out the thousands separator character. */
|
||
#ifdef USE_WIDE_CHAR
|
||
thousands = _NL_CURRENT_WORD (LC_NUMERIC,
|
||
_NL_NUMERIC_THOUSANDS_SEP_WC);
|
||
if (thousands == L'\0')
|
||
grouping = NULL;
|
||
#else
|
||
thousands = _NL_CURRENT (LC_NUMERIC, THOUSANDS_SEP);
|
||
if (*thousands == '\0')
|
||
{
|
||
thousands = NULL;
|
||
grouping = NULL;
|
||
}
|
||
#endif
|
||
}
|
||
}
|
||
else
|
||
grouping = NULL;
|
||
|
||
/* Find the locale's decimal point character. */
|
||
#ifdef USE_WIDE_CHAR
|
||
decimal = _NL_CURRENT_WORD (LC_NUMERIC, _NL_NUMERIC_DECIMAL_POINT_WC);
|
||
assert (decimal != L'\0');
|
||
# define decimal_len 1
|
||
#else
|
||
decimal = _NL_CURRENT (LC_NUMERIC, DECIMAL_POINT);
|
||
decimal_len = strlen (decimal);
|
||
assert (decimal_len > 0);
|
||
#endif
|
||
|
||
/* Prepare number representation. */
|
||
exponent = 0;
|
||
negative = 0;
|
||
bits = 0;
|
||
|
||
/* Parse string to get maximal legal prefix. We need the number of
|
||
characters of the integer part, the fractional part and the exponent. */
|
||
cp = nptr - 1;
|
||
/* Ignore leading white space. */
|
||
do
|
||
c = *++cp;
|
||
while (ISSPACE (c));
|
||
|
||
/* Get sign of the result. */
|
||
if (c == L_('-'))
|
||
{
|
||
negative = 1;
|
||
c = *++cp;
|
||
}
|
||
else if (c == L_('+'))
|
||
c = *++cp;
|
||
|
||
/* Return 0.0 if no legal string is found.
|
||
No character is used even if a sign was found. */
|
||
#ifdef USE_WIDE_CHAR
|
||
if (c == (wint_t) decimal
|
||
&& (wint_t) cp[1] >= L'0' && (wint_t) cp[1] <= L'9')
|
||
{
|
||
/* We accept it. This funny construct is here only to indent
|
||
the code directly. */
|
||
}
|
||
#else
|
||
for (cnt = 0; decimal[cnt] != '\0'; ++cnt)
|
||
if (cp[cnt] != decimal[cnt])
|
||
break;
|
||
if (decimal[cnt] == '\0' && cp[cnt] >= '0' && cp[cnt] <= '9')
|
||
{
|
||
/* We accept it. This funny construct is here only to indent
|
||
the code directly. */
|
||
}
|
||
#endif
|
||
else if (c < L_('0') || c > L_('9'))
|
||
{
|
||
/* Check for `INF' or `INFINITY'. */
|
||
if (TOLOWER_C (c) == L_('i') && STRNCASECMP (cp, L_("inf"), 3) == 0)
|
||
{
|
||
/* Return +/- infinity. */
|
||
if (endptr != NULL)
|
||
*endptr = (STRING_TYPE *)
|
||
(cp + (STRNCASECMP (cp + 3, L_("inity"), 5) == 0
|
||
? 8 : 3));
|
||
|
||
return negative ? -FLOAT_HUGE_VAL : FLOAT_HUGE_VAL;
|
||
}
|
||
|
||
if (TOLOWER_C (c) == L_('n') && STRNCASECMP (cp, L_("nan"), 3) == 0)
|
||
{
|
||
/* Return NaN. */
|
||
FLOAT retval = NAN;
|
||
|
||
cp += 3;
|
||
|
||
/* Match `(n-char-sequence-digit)'. */
|
||
if (*cp == L_('('))
|
||
{
|
||
const STRING_TYPE *startp = cp;
|
||
do
|
||
++cp;
|
||
while ((*cp >= L_('0') && *cp <= L_('9'))
|
||
|| (TOLOWER (*cp) >= L_('a') && TOLOWER (*cp) <= L_('z'))
|
||
|| *cp == L_('_'));
|
||
|
||
if (*cp != L_(')'))
|
||
/* The closing brace is missing. Only match the NAN
|
||
part. */
|
||
cp = startp;
|
||
else
|
||
{
|
||
/* This is a system-dependent way to specify the
|
||
bitmask used for the NaN. We expect it to be
|
||
a number which is put in the mantissa of the
|
||
number. */
|
||
STRING_TYPE *endp;
|
||
unsigned long long int mant;
|
||
|
||
mant = STRTOULL (startp + 1, &endp, 0);
|
||
if (endp == cp)
|
||
SET_MANTISSA (retval, mant);
|
||
}
|
||
}
|
||
|
||
if (endptr != NULL)
|
||
*endptr = (STRING_TYPE *) cp;
|
||
|
||
return retval;
|
||
}
|
||
|
||
/* It is really a text we do not recognize. */
|
||
RETURN (0.0, nptr);
|
||
}
|
||
|
||
/* First look whether we are faced with a hexadecimal number. */
|
||
if (c == L_('0') && TOLOWER (cp[1]) == L_('x'))
|
||
{
|
||
/* Okay, it is a hexa-decimal number. Remember this and skip
|
||
the characters. BTW: hexadecimal numbers must not be
|
||
grouped. */
|
||
base = 16;
|
||
cp += 2;
|
||
c = *cp;
|
||
grouping = NULL;
|
||
}
|
||
|
||
/* Record the start of the digits, in case we will check their grouping. */
|
||
start_of_digits = startp = cp;
|
||
|
||
/* Ignore leading zeroes. This helps us to avoid useless computations. */
|
||
#ifdef USE_WIDE_CHAR
|
||
while (c == L'0' || ((wint_t) thousands != L'\0' && c == (wint_t) thousands))
|
||
c = *++cp;
|
||
#else
|
||
if (thousands == NULL)
|
||
while (c == '0')
|
||
c = *++cp;
|
||
else
|
||
{
|
||
/* We also have the multibyte thousands string. */
|
||
while (1)
|
||
{
|
||
if (c != '0')
|
||
{
|
||
for (cnt = 0; thousands[cnt] != '\0'; ++cnt)
|
||
if (c != thousands[cnt])
|
||
break;
|
||
if (thousands[cnt] != '\0')
|
||
break;
|
||
}
|
||
c = *++cp;
|
||
}
|
||
}
|
||
#endif
|
||
|
||
/* If no other digit but a '0' is found the result is 0.0.
|
||
Return current read pointer. */
|
||
if ((c < L_('0') || c > L_('9'))
|
||
&& (base == 16 && (c < (CHAR_TYPE) TOLOWER (L_('a'))
|
||
|| c > (CHAR_TYPE) TOLOWER (L_('f'))))
|
||
#ifdef USE_WIDE_CHAR
|
||
&& c != (wint_t) decimal
|
||
#else
|
||
&& ({ for (cnt = 0; decimal[cnt] != '\0'; ++cnt)
|
||
if (decimal[cnt] != cp[cnt])
|
||
break;
|
||
decimal[cnt] != '\0'; })
|
||
#endif
|
||
&& (base == 16 && (cp == start_of_digits
|
||
|| (CHAR_TYPE) TOLOWER (c) != L_('p')))
|
||
&& (base != 16 && (CHAR_TYPE) TOLOWER (c) != L_('e')))
|
||
{
|
||
#ifdef USE_WIDE_CHAR
|
||
tp = __correctly_grouped_prefixwc (start_of_digits, cp, thousands,
|
||
grouping);
|
||
#else
|
||
tp = __correctly_grouped_prefixmb (start_of_digits, cp, thousands,
|
||
grouping);
|
||
#endif
|
||
/* If TP is at the start of the digits, there was no correctly
|
||
grouped prefix of the string; so no number found. */
|
||
RETURN (0.0, tp == start_of_digits ? (base == 16 ? cp - 1 : nptr) : tp);
|
||
}
|
||
|
||
/* Remember first significant digit and read following characters until the
|
||
decimal point, exponent character or any non-FP number character. */
|
||
startp = cp;
|
||
dig_no = 0;
|
||
while (1)
|
||
{
|
||
if ((c >= L_('0') && c <= L_('9'))
|
||
|| (base == 16 && (wint_t) TOLOWER (c) >= L_('a')
|
||
&& (wint_t) TOLOWER (c) <= L_('f')))
|
||
++dig_no;
|
||
else
|
||
{
|
||
#ifdef USE_WIDE_CHAR
|
||
if ((wint_t) thousands == L'\0' || c != (wint_t) thousands)
|
||
/* Not a digit or separator: end of the integer part. */
|
||
break;
|
||
#else
|
||
if (thousands == NULL)
|
||
break;
|
||
else
|
||
{
|
||
for (cnt = 0; thousands[cnt] != '\0'; ++cnt)
|
||
if (thousands[cnt] != cp[cnt])
|
||
break;
|
||
if (thousands[cnt] != '\0')
|
||
break;
|
||
}
|
||
#endif
|
||
}
|
||
c = *++cp;
|
||
}
|
||
|
||
if (grouping && dig_no > 0)
|
||
{
|
||
/* Check the grouping of the digits. */
|
||
#ifdef USE_WIDE_CHAR
|
||
tp = __correctly_grouped_prefixwc (start_of_digits, cp, thousands,
|
||
grouping);
|
||
#else
|
||
tp = __correctly_grouped_prefixmb (start_of_digits, cp, thousands,
|
||
grouping);
|
||
#endif
|
||
if (cp != tp)
|
||
{
|
||
/* Less than the entire string was correctly grouped. */
|
||
|
||
if (tp == start_of_digits)
|
||
/* No valid group of numbers at all: no valid number. */
|
||
RETURN (0.0, nptr);
|
||
|
||
if (tp < startp)
|
||
/* The number is validly grouped, but consists
|
||
only of zeroes. The whole value is zero. */
|
||
RETURN (0.0, tp);
|
||
|
||
/* Recompute DIG_NO so we won't read more digits than
|
||
are properly grouped. */
|
||
cp = tp;
|
||
dig_no = 0;
|
||
for (tp = startp; tp < cp; ++tp)
|
||
if (*tp >= L_('0') && *tp <= L_('9'))
|
||
++dig_no;
|
||
|
||
int_no = dig_no;
|
||
lead_zero = 0;
|
||
|
||
goto number_parsed;
|
||
}
|
||
}
|
||
|
||
/* We have the number digits in the integer part. Whether these are all or
|
||
any is really a fractional digit will be decided later. */
|
||
int_no = dig_no;
|
||
lead_zero = int_no == 0 ? -1 : 0;
|
||
|
||
/* Read the fractional digits. A special case are the 'american style'
|
||
numbers like `16.' i.e. with decimal but without trailing digits. */
|
||
if (
|
||
#ifdef USE_WIDE_CHAR
|
||
c == (wint_t) decimal
|
||
#else
|
||
({ for (cnt = 0; decimal[cnt] != '\0'; ++cnt)
|
||
if (decimal[cnt] != cp[cnt])
|
||
break;
|
||
decimal[cnt] == '\0'; })
|
||
#endif
|
||
)
|
||
{
|
||
cp += decimal_len;
|
||
c = *cp;
|
||
while ((c >= L_('0') && c <= L_('9')) ||
|
||
(base == 16 && TOLOWER (c) >= L_('a') && TOLOWER (c) <= L_('f')))
|
||
{
|
||
if (c != L_('0') && lead_zero == -1)
|
||
lead_zero = dig_no - int_no;
|
||
++dig_no;
|
||
c = *++cp;
|
||
}
|
||
}
|
||
|
||
/* Remember start of exponent (if any). */
|
||
expp = cp;
|
||
|
||
/* Read exponent. */
|
||
if ((base == 16 && TOLOWER (c) == L_('p'))
|
||
|| (base != 16 && TOLOWER (c) == L_('e')))
|
||
{
|
||
int exp_negative = 0;
|
||
|
||
c = *++cp;
|
||
if (c == L_('-'))
|
||
{
|
||
exp_negative = 1;
|
||
c = *++cp;
|
||
}
|
||
else if (c == L_('+'))
|
||
c = *++cp;
|
||
|
||
if (c >= L_('0') && c <= L_('9'))
|
||
{
|
||
int exp_limit;
|
||
|
||
/* Get the exponent limit. */
|
||
if (base == 16)
|
||
exp_limit = (exp_negative ?
|
||
-MIN_EXP + MANT_DIG + 4 * int_no :
|
||
MAX_EXP - 4 * int_no + lead_zero);
|
||
else
|
||
exp_limit = (exp_negative ?
|
||
-MIN_10_EXP + MANT_DIG + int_no :
|
||
MAX_10_EXP - int_no + lead_zero);
|
||
|
||
do
|
||
{
|
||
exponent *= 10;
|
||
|
||
if (exponent > exp_limit)
|
||
/* The exponent is too large/small to represent a valid
|
||
number. */
|
||
{
|
||
FLOAT result;
|
||
|
||
/* We have to take care for special situation: a joker
|
||
might have written "0.0e100000" which is in fact
|
||
zero. */
|
||
if (lead_zero == -1)
|
||
result = negative ? -0.0 : 0.0;
|
||
else
|
||
{
|
||
/* Overflow or underflow. */
|
||
__set_errno (ERANGE);
|
||
result = (exp_negative ? 0.0 :
|
||
negative ? -FLOAT_HUGE_VAL : FLOAT_HUGE_VAL);
|
||
}
|
||
|
||
/* Accept all following digits as part of the exponent. */
|
||
do
|
||
++cp;
|
||
while (*cp >= L_('0') && *cp <= L_('9'));
|
||
|
||
RETURN (result, cp);
|
||
/* NOTREACHED */
|
||
}
|
||
|
||
exponent += c - L_('0');
|
||
c = *++cp;
|
||
}
|
||
while (c >= L_('0') && c <= L_('9'));
|
||
|
||
if (exp_negative)
|
||
exponent = -exponent;
|
||
}
|
||
else
|
||
cp = expp;
|
||
}
|
||
|
||
/* We don't want to have to work with trailing zeroes after the radix. */
|
||
if (dig_no > int_no)
|
||
{
|
||
while (expp[-1] == L_('0'))
|
||
{
|
||
--expp;
|
||
--dig_no;
|
||
}
|
||
assert (dig_no >= int_no);
|
||
}
|
||
|
||
if (dig_no == int_no && dig_no > 0 && exponent < 0)
|
||
do
|
||
{
|
||
while (! (base == 16 ? ISXDIGIT (expp[-1]) : ISDIGIT (expp[-1])))
|
||
--expp;
|
||
|
||
if (expp[-1] != L_('0'))
|
||
break;
|
||
|
||
--expp;
|
||
--dig_no;
|
||
--int_no;
|
||
++exponent;
|
||
}
|
||
while (dig_no > 0 && exponent < 0);
|
||
|
||
number_parsed:
|
||
|
||
/* The whole string is parsed. Store the address of the next character. */
|
||
if (endptr)
|
||
*endptr = (STRING_TYPE *) cp;
|
||
|
||
if (dig_no == 0)
|
||
return negative ? -0.0 : 0.0;
|
||
|
||
if (lead_zero)
|
||
{
|
||
/* Find the decimal point */
|
||
#ifdef USE_WIDE_CHAR
|
||
while (*startp != decimal)
|
||
++startp;
|
||
#else
|
||
while (1)
|
||
{
|
||
if (*startp == decimal[0])
|
||
{
|
||
for (cnt = 1; decimal[cnt] != '\0'; ++cnt)
|
||
if (decimal[cnt] != startp[cnt])
|
||
break;
|
||
if (decimal[cnt] == '\0')
|
||
break;
|
||
}
|
||
++startp;
|
||
}
|
||
#endif
|
||
startp += lead_zero + decimal_len;
|
||
exponent -= base == 16 ? 4 * lead_zero : lead_zero;
|
||
dig_no -= lead_zero;
|
||
}
|
||
|
||
/* If the BASE is 16 we can use a simpler algorithm. */
|
||
if (base == 16)
|
||
{
|
||
static const int nbits[16] = { 0, 1, 2, 2, 3, 3, 3, 3,
|
||
4, 4, 4, 4, 4, 4, 4, 4 };
|
||
int idx = (MANT_DIG - 1) / BITS_PER_MP_LIMB;
|
||
int pos = (MANT_DIG - 1) % BITS_PER_MP_LIMB;
|
||
mp_limb_t val;
|
||
|
||
while (!ISXDIGIT (*startp))
|
||
++startp;
|
||
while (*startp == L_('0'))
|
||
++startp;
|
||
if (ISDIGIT (*startp))
|
||
val = *startp++ - L_('0');
|
||
else
|
||
val = 10 + TOLOWER (*startp++) - L_('a');
|
||
bits = nbits[val];
|
||
/* We cannot have a leading zero. */
|
||
assert (bits != 0);
|
||
|
||
if (pos + 1 >= 4 || pos + 1 >= bits)
|
||
{
|
||
/* We don't have to care for wrapping. This is the normal
|
||
case so we add the first clause in the `if' expression as
|
||
an optimization. It is a compile-time constant and so does
|
||
not cost anything. */
|
||
retval[idx] = val << (pos - bits + 1);
|
||
pos -= bits;
|
||
}
|
||
else
|
||
{
|
||
retval[idx--] = val >> (bits - pos - 1);
|
||
retval[idx] = val << (BITS_PER_MP_LIMB - (bits - pos - 1));
|
||
pos = BITS_PER_MP_LIMB - 1 - (bits - pos - 1);
|
||
}
|
||
|
||
/* Adjust the exponent for the bits we are shifting in. */
|
||
exponent += bits - 1 + (int_no - 1) * 4;
|
||
|
||
while (--dig_no > 0 && idx >= 0)
|
||
{
|
||
if (!ISXDIGIT (*startp))
|
||
startp += decimal_len;
|
||
if (ISDIGIT (*startp))
|
||
val = *startp++ - L_('0');
|
||
else
|
||
val = 10 + TOLOWER (*startp++) - L_('a');
|
||
|
||
if (pos + 1 >= 4)
|
||
{
|
||
retval[idx] |= val << (pos - 4 + 1);
|
||
pos -= 4;
|
||
}
|
||
else
|
||
{
|
||
retval[idx--] |= val >> (4 - pos - 1);
|
||
val <<= BITS_PER_MP_LIMB - (4 - pos - 1);
|
||
if (idx < 0)
|
||
return round_and_return (retval, exponent, negative, val,
|
||
BITS_PER_MP_LIMB - 1, dig_no > 0);
|
||
|
||
retval[idx] = val;
|
||
pos = BITS_PER_MP_LIMB - 1 - (4 - pos - 1);
|
||
}
|
||
}
|
||
|
||
/* We ran out of digits. */
|
||
MPN_ZERO (retval, idx);
|
||
|
||
return round_and_return (retval, exponent, negative, 0, 0, 0);
|
||
}
|
||
|
||
/* Now we have the number of digits in total and the integer digits as well
|
||
as the exponent and its sign. We can decide whether the read digits are
|
||
really integer digits or belong to the fractional part; i.e. we normalize
|
||
123e-2 to 1.23. */
|
||
{
|
||
register int incr = (exponent < 0 ? MAX (-int_no, exponent)
|
||
: MIN (dig_no - int_no, exponent));
|
||
int_no += incr;
|
||
exponent -= incr;
|
||
}
|
||
|
||
if (int_no + exponent > MAX_10_EXP + 1)
|
||
{
|
||
__set_errno (ERANGE);
|
||
return negative ? -FLOAT_HUGE_VAL : FLOAT_HUGE_VAL;
|
||
}
|
||
|
||
if (exponent < MIN_10_EXP - (DIG + 1))
|
||
{
|
||
__set_errno (ERANGE);
|
||
return 0.0;
|
||
}
|
||
|
||
if (int_no > 0)
|
||
{
|
||
/* Read the integer part as a multi-precision number to NUM. */
|
||
startp = str_to_mpn (startp, int_no, num, &numsize, &exponent
|
||
#ifndef USE_WIDE_CHAR
|
||
, decimal, decimal_len, thousands
|
||
#endif
|
||
);
|
||
|
||
if (exponent > 0)
|
||
{
|
||
/* We now multiply the gained number by the given power of ten. */
|
||
mp_limb_t *psrc = num;
|
||
mp_limb_t *pdest = den;
|
||
int expbit = 1;
|
||
const struct mp_power *ttab = &_fpioconst_pow10[0];
|
||
|
||
do
|
||
{
|
||
if ((exponent & expbit) != 0)
|
||
{
|
||
size_t size = ttab->arraysize - _FPIO_CONST_OFFSET;
|
||
mp_limb_t cy;
|
||
exponent ^= expbit;
|
||
|
||
/* FIXME: not the whole multiplication has to be
|
||
done. If we have the needed number of bits we
|
||
only need the information whether more non-zero
|
||
bits follow. */
|
||
if (numsize >= ttab->arraysize - _FPIO_CONST_OFFSET)
|
||
cy = __mpn_mul (pdest, psrc, numsize,
|
||
&__tens[ttab->arrayoff
|
||
+ _FPIO_CONST_OFFSET],
|
||
size);
|
||
else
|
||
cy = __mpn_mul (pdest, &__tens[ttab->arrayoff
|
||
+ _FPIO_CONST_OFFSET],
|
||
size, psrc, numsize);
|
||
numsize += size;
|
||
if (cy == 0)
|
||
--numsize;
|
||
(void) SWAP (psrc, pdest);
|
||
}
|
||
expbit <<= 1;
|
||
++ttab;
|
||
}
|
||
while (exponent != 0);
|
||
|
||
if (psrc == den)
|
||
memcpy (num, den, numsize * sizeof (mp_limb_t));
|
||
}
|
||
|
||
/* Determine how many bits of the result we already have. */
|
||
count_leading_zeros (bits, num[numsize - 1]);
|
||
bits = numsize * BITS_PER_MP_LIMB - bits;
|
||
|
||
/* Now we know the exponent of the number in base two.
|
||
Check it against the maximum possible exponent. */
|
||
if (bits > MAX_EXP)
|
||
{
|
||
__set_errno (ERANGE);
|
||
return negative ? -FLOAT_HUGE_VAL : FLOAT_HUGE_VAL;
|
||
}
|
||
|
||
/* We have already the first BITS bits of the result. Together with
|
||
the information whether more non-zero bits follow this is enough
|
||
to determine the result. */
|
||
if (bits > MANT_DIG)
|
||
{
|
||
int i;
|
||
const mp_size_t least_idx = (bits - MANT_DIG) / BITS_PER_MP_LIMB;
|
||
const mp_size_t least_bit = (bits - MANT_DIG) % BITS_PER_MP_LIMB;
|
||
const mp_size_t round_idx = least_bit == 0 ? least_idx - 1
|
||
: least_idx;
|
||
const mp_size_t round_bit = least_bit == 0 ? BITS_PER_MP_LIMB - 1
|
||
: least_bit - 1;
|
||
|
||
if (least_bit == 0)
|
||
memcpy (retval, &num[least_idx],
|
||
RETURN_LIMB_SIZE * sizeof (mp_limb_t));
|
||
else
|
||
{
|
||
for (i = least_idx; i < numsize - 1; ++i)
|
||
retval[i - least_idx] = (num[i] >> least_bit)
|
||
| (num[i + 1]
|
||
<< (BITS_PER_MP_LIMB - least_bit));
|
||
if (i - least_idx < RETURN_LIMB_SIZE)
|
||
retval[RETURN_LIMB_SIZE - 1] = num[i] >> least_bit;
|
||
}
|
||
|
||
/* Check whether any limb beside the ones in RETVAL are non-zero. */
|
||
for (i = 0; num[i] == 0; ++i)
|
||
;
|
||
|
||
return round_and_return (retval, bits - 1, negative,
|
||
num[round_idx], round_bit,
|
||
int_no < dig_no || i < round_idx);
|
||
/* NOTREACHED */
|
||
}
|
||
else if (dig_no == int_no)
|
||
{
|
||
const mp_size_t target_bit = (MANT_DIG - 1) % BITS_PER_MP_LIMB;
|
||
const mp_size_t is_bit = (bits - 1) % BITS_PER_MP_LIMB;
|
||
|
||
if (target_bit == is_bit)
|
||
{
|
||
memcpy (&retval[RETURN_LIMB_SIZE - numsize], num,
|
||
numsize * sizeof (mp_limb_t));
|
||
/* FIXME: the following loop can be avoided if we assume a
|
||
maximal MANT_DIG value. */
|
||
MPN_ZERO (retval, RETURN_LIMB_SIZE - numsize);
|
||
}
|
||
else if (target_bit > is_bit)
|
||
{
|
||
(void) __mpn_lshift (&retval[RETURN_LIMB_SIZE - numsize],
|
||
num, numsize, target_bit - is_bit);
|
||
/* FIXME: the following loop can be avoided if we assume a
|
||
maximal MANT_DIG value. */
|
||
MPN_ZERO (retval, RETURN_LIMB_SIZE - numsize);
|
||
}
|
||
else
|
||
{
|
||
mp_limb_t cy;
|
||
assert (numsize < RETURN_LIMB_SIZE);
|
||
|
||
cy = __mpn_rshift (&retval[RETURN_LIMB_SIZE - numsize],
|
||
num, numsize, is_bit - target_bit);
|
||
retval[RETURN_LIMB_SIZE - numsize - 1] = cy;
|
||
/* FIXME: the following loop can be avoided if we assume a
|
||
maximal MANT_DIG value. */
|
||
MPN_ZERO (retval, RETURN_LIMB_SIZE - numsize - 1);
|
||
}
|
||
|
||
return round_and_return (retval, bits - 1, negative, 0, 0, 0);
|
||
/* NOTREACHED */
|
||
}
|
||
|
||
/* Store the bits we already have. */
|
||
memcpy (retval, num, numsize * sizeof (mp_limb_t));
|
||
#if RETURN_LIMB_SIZE > 1
|
||
if (numsize < RETURN_LIMB_SIZE)
|
||
# if RETURN_LIMB_SIZE == 2
|
||
retval[numsize] = 0;
|
||
# else
|
||
MPN_ZERO (retval + numsize, RETURN_LIMB_SIZE - numsize);
|
||
# endif
|
||
#endif
|
||
}
|
||
|
||
/* We have to compute at least some of the fractional digits. */
|
||
{
|
||
/* We construct a fraction and the result of the division gives us
|
||
the needed digits. The denominator is 1.0 multiplied by the
|
||
exponent of the lowest digit; i.e. 0.123 gives 123 / 1000 and
|
||
123e-6 gives 123 / 1000000. */
|
||
|
||
int expbit;
|
||
int neg_exp;
|
||
int more_bits;
|
||
mp_limb_t cy;
|
||
mp_limb_t *psrc = den;
|
||
mp_limb_t *pdest = num;
|
||
const struct mp_power *ttab = &_fpioconst_pow10[0];
|
||
|
||
assert (dig_no > int_no && exponent <= 0);
|
||
|
||
|
||
/* For the fractional part we need not process too many digits. One
|
||
decimal digits gives us log_2(10) ~ 3.32 bits. If we now compute
|
||
ceil(BITS / 3) =: N
|
||
digits we should have enough bits for the result. The remaining
|
||
decimal digits give us the information that more bits are following.
|
||
This can be used while rounding. (Two added as a safety margin.) */
|
||
if (dig_no - int_no > (MANT_DIG - bits + 2) / 3 + 2)
|
||
{
|
||
dig_no = int_no + (MANT_DIG - bits + 2) / 3 + 2;
|
||
more_bits = 1;
|
||
}
|
||
else
|
||
more_bits = 0;
|
||
|
||
neg_exp = dig_no - int_no - exponent;
|
||
|
||
/* Construct the denominator. */
|
||
densize = 0;
|
||
expbit = 1;
|
||
do
|
||
{
|
||
if ((neg_exp & expbit) != 0)
|
||
{
|
||
mp_limb_t cy;
|
||
neg_exp ^= expbit;
|
||
|
||
if (densize == 0)
|
||
{
|
||
densize = ttab->arraysize - _FPIO_CONST_OFFSET;
|
||
memcpy (psrc, &__tens[ttab->arrayoff + _FPIO_CONST_OFFSET],
|
||
densize * sizeof (mp_limb_t));
|
||
}
|
||
else
|
||
{
|
||
cy = __mpn_mul (pdest, &__tens[ttab->arrayoff
|
||
+ _FPIO_CONST_OFFSET],
|
||
ttab->arraysize - _FPIO_CONST_OFFSET,
|
||
psrc, densize);
|
||
densize += ttab->arraysize - _FPIO_CONST_OFFSET;
|
||
if (cy == 0)
|
||
--densize;
|
||
(void) SWAP (psrc, pdest);
|
||
}
|
||
}
|
||
expbit <<= 1;
|
||
++ttab;
|
||
}
|
||
while (neg_exp != 0);
|
||
|
||
if (psrc == num)
|
||
memcpy (den, num, densize * sizeof (mp_limb_t));
|
||
|
||
/* Read the fractional digits from the string. */
|
||
(void) str_to_mpn (startp, dig_no - int_no, num, &numsize, &exponent
|
||
#ifndef USE_WIDE_CHAR
|
||
, decimal, decimal_len, thousands
|
||
#endif
|
||
);
|
||
|
||
/* We now have to shift both numbers so that the highest bit in the
|
||
denominator is set. In the same process we copy the numerator to
|
||
a high place in the array so that the division constructs the wanted
|
||
digits. This is done by a "quasi fix point" number representation.
|
||
|
||
num: ddddddddddd . 0000000000000000000000
|
||
|--- m ---|
|
||
den: ddddddddddd n >= m
|
||
|--- n ---|
|
||
*/
|
||
|
||
count_leading_zeros (cnt, den[densize - 1]);
|
||
|
||
if (cnt > 0)
|
||
{
|
||
/* Don't call `mpn_shift' with a count of zero since the specification
|
||
does not allow this. */
|
||
(void) __mpn_lshift (den, den, densize, cnt);
|
||
cy = __mpn_lshift (num, num, numsize, cnt);
|
||
if (cy != 0)
|
||
num[numsize++] = cy;
|
||
}
|
||
|
||
/* Now we are ready for the division. But it is not necessary to
|
||
do a full multi-precision division because we only need a small
|
||
number of bits for the result. So we do not use __mpn_divmod
|
||
here but instead do the division here by hand and stop whenever
|
||
the needed number of bits is reached. The code itself comes
|
||
from the GNU MP Library by Torbj\"orn Granlund. */
|
||
|
||
exponent = bits;
|
||
|
||
switch (densize)
|
||
{
|
||
case 1:
|
||
{
|
||
mp_limb_t d, n, quot;
|
||
int used = 0;
|
||
|
||
n = num[0];
|
||
d = den[0];
|
||
assert (numsize == 1 && n < d);
|
||
|
||
do
|
||
{
|
||
udiv_qrnnd (quot, n, n, 0, d);
|
||
|
||
#define got_limb \
|
||
if (bits == 0) \
|
||
{ \
|
||
register int cnt; \
|
||
if (quot == 0) \
|
||
cnt = BITS_PER_MP_LIMB; \
|
||
else \
|
||
count_leading_zeros (cnt, quot); \
|
||
exponent -= cnt; \
|
||
if (BITS_PER_MP_LIMB - cnt > MANT_DIG) \
|
||
{ \
|
||
used = MANT_DIG + cnt; \
|
||
retval[0] = quot >> (BITS_PER_MP_LIMB - used); \
|
||
bits = MANT_DIG + 1; \
|
||
} \
|
||
else \
|
||
{ \
|
||
/* Note that we only clear the second element. */ \
|
||
/* The conditional is determined at compile time. */ \
|
||
if (RETURN_LIMB_SIZE > 1) \
|
||
retval[1] = 0; \
|
||
retval[0] = quot; \
|
||
bits = -cnt; \
|
||
} \
|
||
} \
|
||
else if (bits + BITS_PER_MP_LIMB <= MANT_DIG) \
|
||
__mpn_lshift_1 (retval, RETURN_LIMB_SIZE, BITS_PER_MP_LIMB, \
|
||
quot); \
|
||
else \
|
||
{ \
|
||
used = MANT_DIG - bits; \
|
||
if (used > 0) \
|
||
__mpn_lshift_1 (retval, RETURN_LIMB_SIZE, used, quot); \
|
||
} \
|
||
bits += BITS_PER_MP_LIMB
|
||
|
||
got_limb;
|
||
}
|
||
while (bits <= MANT_DIG);
|
||
|
||
return round_and_return (retval, exponent - 1, negative,
|
||
quot, BITS_PER_MP_LIMB - 1 - used,
|
||
more_bits || n != 0);
|
||
}
|
||
case 2:
|
||
{
|
||
mp_limb_t d0, d1, n0, n1;
|
||
mp_limb_t quot = 0;
|
||
int used = 0;
|
||
|
||
d0 = den[0];
|
||
d1 = den[1];
|
||
|
||
if (numsize < densize)
|
||
{
|
||
if (num[0] >= d1)
|
||
{
|
||
/* The numerator of the number occupies fewer bits than
|
||
the denominator but the one limb is bigger than the
|
||
high limb of the numerator. */
|
||
n1 = 0;
|
||
n0 = num[0];
|
||
}
|
||
else
|
||
{
|
||
if (bits <= 0)
|
||
exponent -= BITS_PER_MP_LIMB;
|
||
else
|
||
{
|
||
if (bits + BITS_PER_MP_LIMB <= MANT_DIG)
|
||
__mpn_lshift_1 (retval, RETURN_LIMB_SIZE,
|
||
BITS_PER_MP_LIMB, 0);
|
||
else
|
||
{
|
||
used = MANT_DIG - bits;
|
||
if (used > 0)
|
||
__mpn_lshift_1 (retval, RETURN_LIMB_SIZE, used, 0);
|
||
}
|
||
bits += BITS_PER_MP_LIMB;
|
||
}
|
||
n1 = num[0];
|
||
n0 = 0;
|
||
}
|
||
}
|
||
else
|
||
{
|
||
n1 = num[1];
|
||
n0 = num[0];
|
||
}
|
||
|
||
while (bits <= MANT_DIG)
|
||
{
|
||
mp_limb_t r;
|
||
|
||
if (n1 == d1)
|
||
{
|
||
/* QUOT should be either 111..111 or 111..110. We need
|
||
special treatment of this rare case as normal division
|
||
would give overflow. */
|
||
quot = ~(mp_limb_t) 0;
|
||
|
||
r = n0 + d1;
|
||
if (r < d1) /* Carry in the addition? */
|
||
{
|
||
add_ssaaaa (n1, n0, r - d0, 0, 0, d0);
|
||
goto have_quot;
|
||
}
|
||
n1 = d0 - (d0 != 0);
|
||
n0 = -d0;
|
||
}
|
||
else
|
||
{
|
||
udiv_qrnnd (quot, r, n1, n0, d1);
|
||
umul_ppmm (n1, n0, d0, quot);
|
||
}
|
||
|
||
q_test:
|
||
if (n1 > r || (n1 == r && n0 > 0))
|
||
{
|
||
/* The estimated QUOT was too large. */
|
||
--quot;
|
||
|
||
sub_ddmmss (n1, n0, n1, n0, 0, d0);
|
||
r += d1;
|
||
if (r >= d1) /* If not carry, test QUOT again. */
|
||
goto q_test;
|
||
}
|
||
sub_ddmmss (n1, n0, r, 0, n1, n0);
|
||
|
||
have_quot:
|
||
got_limb;
|
||
}
|
||
|
||
return round_and_return (retval, exponent - 1, negative,
|
||
quot, BITS_PER_MP_LIMB - 1 - used,
|
||
more_bits || n1 != 0 || n0 != 0);
|
||
}
|
||
default:
|
||
{
|
||
int i;
|
||
mp_limb_t cy, dX, d1, n0, n1;
|
||
mp_limb_t quot = 0;
|
||
int used = 0;
|
||
|
||
dX = den[densize - 1];
|
||
d1 = den[densize - 2];
|
||
|
||
/* The division does not work if the upper limb of the two-limb
|
||
numerator is greater than the denominator. */
|
||
if (__mpn_cmp (num, &den[densize - numsize], numsize) > 0)
|
||
num[numsize++] = 0;
|
||
|
||
if (numsize < densize)
|
||
{
|
||
mp_size_t empty = densize - numsize;
|
||
register int i;
|
||
|
||
if (bits <= 0)
|
||
exponent -= empty * BITS_PER_MP_LIMB;
|
||
else
|
||
{
|
||
if (bits + empty * BITS_PER_MP_LIMB <= MANT_DIG)
|
||
{
|
||
/* We make a difference here because the compiler
|
||
cannot optimize the `else' case that good and
|
||
this reflects all currently used FLOAT types
|
||
and GMP implementations. */
|
||
#if RETURN_LIMB_SIZE <= 2
|
||
assert (empty == 1);
|
||
__mpn_lshift_1 (retval, RETURN_LIMB_SIZE,
|
||
BITS_PER_MP_LIMB, 0);
|
||
#else
|
||
for (i = RETURN_LIMB_SIZE - 1; i >= empty; --i)
|
||
retval[i] = retval[i - empty];
|
||
while (i >= 0)
|
||
retval[i--] = 0;
|
||
#endif
|
||
}
|
||
else
|
||
{
|
||
used = MANT_DIG - bits;
|
||
if (used >= BITS_PER_MP_LIMB)
|
||
{
|
||
register int i;
|
||
(void) __mpn_lshift (&retval[used
|
||
/ BITS_PER_MP_LIMB],
|
||
retval, RETURN_LIMB_SIZE,
|
||
used % BITS_PER_MP_LIMB);
|
||
for (i = used / BITS_PER_MP_LIMB - 1; i >= 0; --i)
|
||
retval[i] = 0;
|
||
}
|
||
else if (used > 0)
|
||
__mpn_lshift_1 (retval, RETURN_LIMB_SIZE, used, 0);
|
||
}
|
||
bits += empty * BITS_PER_MP_LIMB;
|
||
}
|
||
for (i = numsize; i > 0; --i)
|
||
num[i + empty] = num[i - 1];
|
||
MPN_ZERO (num, empty + 1);
|
||
}
|
||
else
|
||
{
|
||
int i;
|
||
assert (numsize == densize);
|
||
for (i = numsize; i > 0; --i)
|
||
num[i] = num[i - 1];
|
||
}
|
||
|
||
den[densize] = 0;
|
||
n0 = num[densize];
|
||
|
||
while (bits <= MANT_DIG)
|
||
{
|
||
if (n0 == dX)
|
||
/* This might over-estimate QUOT, but it's probably not
|
||
worth the extra code here to find out. */
|
||
quot = ~(mp_limb_t) 0;
|
||
else
|
||
{
|
||
mp_limb_t r;
|
||
|
||
udiv_qrnnd (quot, r, n0, num[densize - 1], dX);
|
||
umul_ppmm (n1, n0, d1, quot);
|
||
|
||
while (n1 > r || (n1 == r && n0 > num[densize - 2]))
|
||
{
|
||
--quot;
|
||
r += dX;
|
||
if (r < dX) /* I.e. "carry in previous addition?" */
|
||
break;
|
||
n1 -= n0 < d1;
|
||
n0 -= d1;
|
||
}
|
||
}
|
||
|
||
/* Possible optimization: We already have (q * n0) and (1 * n1)
|
||
after the calculation of QUOT. Taking advantage of this, we
|
||
could make this loop make two iterations less. */
|
||
|
||
cy = __mpn_submul_1 (num, den, densize + 1, quot);
|
||
|
||
if (num[densize] != cy)
|
||
{
|
||
cy = __mpn_add_n (num, num, den, densize);
|
||
assert (cy != 0);
|
||
--quot;
|
||
}
|
||
n0 = num[densize] = num[densize - 1];
|
||
for (i = densize - 1; i > 0; --i)
|
||
num[i] = num[i - 1];
|
||
|
||
got_limb;
|
||
}
|
||
|
||
for (i = densize; num[i] == 0 && i >= 0; --i)
|
||
;
|
||
return round_and_return (retval, exponent - 1, negative,
|
||
quot, BITS_PER_MP_LIMB - 1 - used,
|
||
more_bits || i >= 0);
|
||
}
|
||
}
|
||
}
|
||
|
||
/* NOTREACHED */
|
||
}
|
||
#if defined _LIBC && !defined USE_WIDE_CHAR
|
||
libc_hidden_def (INTERNAL (__STRTOF))
|
||
#endif
|
||
|
||
/* External user entry point. */
|
||
|
||
FLOAT
|
||
#ifdef weak_function
|
||
weak_function
|
||
#endif
|
||
__STRTOF (nptr, endptr, loc)
|
||
const STRING_TYPE *nptr;
|
||
STRING_TYPE **endptr;
|
||
__locale_t loc;
|
||
{
|
||
return INTERNAL (__STRTOF) (nptr, endptr, 0, loc);
|
||
}
|
||
weak_alias (__STRTOF, STRTOF)
|