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/* Macros for the implementation of *cvt functions, long double version.
   Copyright (C) 1996-2021 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 <float.h>

#define FLOAT_TYPE long double
#define FUNC_PREFIX q
#define FLOAT_FMT_FLAG "L"
#define FLOAT_NAME_EXT l
#define FLOAT_MIN_10_EXP LDBL_MIN_10_EXP
/* Actually we have to write (LDBL_DIG + log10 (LDBL_MAX_10_EXP)) but
   we don't have log10 available in the preprocessor.  Since we cannot
   assume anything on the used `long double' format be generous.  */
#define MAXDIG (NDIGIT_MAX + 12)
#define FCVT_MAXDIG (LDBL_MAX_10_EXP + MAXDIG)
#if LDBL_MANT_DIG == 64
# define NDIGIT_MAX 21
#elif LDBL_MANT_DIG == 53
# define NDIGIT_MAX 17
#elif LDBL_MANT_DIG == 113
# define NDIGIT_MAX 36
#elif LDBL_MANT_DIG == 106
# define NDIGIT_MAX 34
#elif LDBL_MANT_DIG == 56
# define NDIGIT_MAX 18
#else
/* See IEEE 854 5.6, table 2 for this formula.  Unfortunately we need a
   compile time constant here, so we cannot use it.  */
# error "NDIGIT_MAX must be precomputed"
# define NDIGIT_MAX (lrint (ceil (M_LN2 / M_LN10 * LDBL_MANT_DIG + 1.0)))
#endif
#if LDBL_MIN_10_EXP == -37
# define FLOAT_MIN_10_NORM	1.0e-37L
#elif LDBL_MIN_10_EXP == -291
# define FLOAT_MIN_10_NORM	1.0e-291L
#elif LDBL_MIN_10_EXP == -307
# define FLOAT_MIN_10_NORM	1.0e-307L
#elif LDBL_MIN_10_EXP == -4931
# define FLOAT_MIN_10_NORM	1.0e-4931L
#else
/* libc can't depend on libm.  */
# error "FLOAT_MIN_10_NORM must be precomputed"
# define FLOAT_MIN_10_NORM	exp10l (LDBL_MIN_10_EXP)
#endif