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/* Supplemental information about the floating-point formats.
Copyright (C) 2007, 2009-2016 Free Software Foundation, Inc.
Written by Bruno Haible <bruno@clisp.org>, 2007.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, see <http://www.gnu.org/licenses/>. */
#ifndef _FLOATPLUS_H
#define _FLOATPLUS_H
#include <float.h>
#include <limits.h>
/* Number of bits in the mantissa of a floating-point number, including the
"hidden bit". */
#if FLT_RADIX == 2
# define FLT_MANT_BIT FLT_MANT_DIG
# define DBL_MANT_BIT DBL_MANT_DIG
# define LDBL_MANT_BIT LDBL_MANT_DIG
#elif FLT_RADIX == 4
# define FLT_MANT_BIT (FLT_MANT_DIG * 2)
# define DBL_MANT_BIT (DBL_MANT_DIG * 2)
# define LDBL_MANT_BIT (LDBL_MANT_DIG * 2)
#elif FLT_RADIX == 16
# define FLT_MANT_BIT (FLT_MANT_DIG * 4)
# define DBL_MANT_BIT (DBL_MANT_DIG * 4)
# define LDBL_MANT_BIT (LDBL_MANT_DIG * 4)
#endif
/* Bit mask that can be used to mask the exponent, as an unsigned number. */
#define FLT_EXP_MASK ((FLT_MAX_EXP - FLT_MIN_EXP) | 7)
#define DBL_EXP_MASK ((DBL_MAX_EXP - DBL_MIN_EXP) | 7)
#define LDBL_EXP_MASK ((LDBL_MAX_EXP - LDBL_MIN_EXP) | 7)
/* Number of bits used for the exponent of a floating-point number, including
the exponent's sign. */
#define FLT_EXP_BIT \
(FLT_EXP_MASK < 0x100 ? 8 : \
FLT_EXP_MASK < 0x200 ? 9 : \
FLT_EXP_MASK < 0x400 ? 10 : \
FLT_EXP_MASK < 0x800 ? 11 : \
FLT_EXP_MASK < 0x1000 ? 12 : \
FLT_EXP_MASK < 0x2000 ? 13 : \
FLT_EXP_MASK < 0x4000 ? 14 : \
FLT_EXP_MASK < 0x8000 ? 15 : \
FLT_EXP_MASK < 0x10000 ? 16 : \
FLT_EXP_MASK < 0x20000 ? 17 : \
FLT_EXP_MASK < 0x40000 ? 18 : \
FLT_EXP_MASK < 0x80000 ? 19 : \
FLT_EXP_MASK < 0x100000 ? 20 : \
FLT_EXP_MASK < 0x200000 ? 21 : \
FLT_EXP_MASK < 0x400000 ? 22 : \
FLT_EXP_MASK < 0x800000 ? 23 : \
FLT_EXP_MASK < 0x1000000 ? 24 : \
FLT_EXP_MASK < 0x2000000 ? 25 : \
FLT_EXP_MASK < 0x4000000 ? 26 : \
FLT_EXP_MASK < 0x8000000 ? 27 : \
FLT_EXP_MASK < 0x10000000 ? 28 : \
FLT_EXP_MASK < 0x20000000 ? 29 : \
FLT_EXP_MASK < 0x40000000 ? 30 : \
FLT_EXP_MASK <= 0x7fffffff ? 31 : \
32)
#define DBL_EXP_BIT \
(DBL_EXP_MASK < 0x100 ? 8 : \
DBL_EXP_MASK < 0x200 ? 9 : \
DBL_EXP_MASK < 0x400 ? 10 : \
DBL_EXP_MASK < 0x800 ? 11 : \
DBL_EXP_MASK < 0x1000 ? 12 : \
DBL_EXP_MASK < 0x2000 ? 13 : \
DBL_EXP_MASK < 0x4000 ? 14 : \
DBL_EXP_MASK < 0x8000 ? 15 : \
DBL_EXP_MASK < 0x10000 ? 16 : \
DBL_EXP_MASK < 0x20000 ? 17 : \
DBL_EXP_MASK < 0x40000 ? 18 : \
DBL_EXP_MASK < 0x80000 ? 19 : \
DBL_EXP_MASK < 0x100000 ? 20 : \
DBL_EXP_MASK < 0x200000 ? 21 : \
DBL_EXP_MASK < 0x400000 ? 22 : \
DBL_EXP_MASK < 0x800000 ? 23 : \
DBL_EXP_MASK < 0x1000000 ? 24 : \
DBL_EXP_MASK < 0x2000000 ? 25 : \
DBL_EXP_MASK < 0x4000000 ? 26 : \
DBL_EXP_MASK < 0x8000000 ? 27 : \
DBL_EXP_MASK < 0x10000000 ? 28 : \
DBL_EXP_MASK < 0x20000000 ? 29 : \
DBL_EXP_MASK < 0x40000000 ? 30 : \
DBL_EXP_MASK <= 0x7fffffff ? 31 : \
32)
#define LDBL_EXP_BIT \
(LDBL_EXP_MASK < 0x100 ? 8 : \
LDBL_EXP_MASK < 0x200 ? 9 : \
LDBL_EXP_MASK < 0x400 ? 10 : \
LDBL_EXP_MASK < 0x800 ? 11 : \
LDBL_EXP_MASK < 0x1000 ? 12 : \
LDBL_EXP_MASK < 0x2000 ? 13 : \
LDBL_EXP_MASK < 0x4000 ? 14 : \
LDBL_EXP_MASK < 0x8000 ? 15 : \
LDBL_EXP_MASK < 0x10000 ? 16 : \
LDBL_EXP_MASK < 0x20000 ? 17 : \
LDBL_EXP_MASK < 0x40000 ? 18 : \
LDBL_EXP_MASK < 0x80000 ? 19 : \
LDBL_EXP_MASK < 0x100000 ? 20 : \
LDBL_EXP_MASK < 0x200000 ? 21 : \
LDBL_EXP_MASK < 0x400000 ? 22 : \
LDBL_EXP_MASK < 0x800000 ? 23 : \
LDBL_EXP_MASK < 0x1000000 ? 24 : \
LDBL_EXP_MASK < 0x2000000 ? 25 : \
LDBL_EXP_MASK < 0x4000000 ? 26 : \
LDBL_EXP_MASK < 0x8000000 ? 27 : \
LDBL_EXP_MASK < 0x10000000 ? 28 : \
LDBL_EXP_MASK < 0x20000000 ? 29 : \
LDBL_EXP_MASK < 0x40000000 ? 30 : \
LDBL_EXP_MASK <= 0x7fffffff ? 31 : \
32)
/* Number of bits used for a floating-point number: the mantissa (not
counting the "hidden bit", since it may or may not be explicit), the
exponent, and the sign. */
#define FLT_TOTAL_BIT ((FLT_MANT_BIT - 1) + FLT_EXP_BIT + 1)
#define DBL_TOTAL_BIT ((DBL_MANT_BIT - 1) + DBL_EXP_BIT + 1)
#define LDBL_TOTAL_BIT ((LDBL_MANT_BIT - 1) + LDBL_EXP_BIT + 1)
/* Number of bytes used for a floating-point number.
This can be smaller than the 'sizeof'. For example, on i386 systems,
'long double' most often have LDBL_MANT_BIT = 64, LDBL_EXP_BIT = 16, hence
LDBL_TOTAL_BIT = 80 bits, i.e. 10 bytes of consecutive memory, but
sizeof (long double) = 12 or = 16. */
#define SIZEOF_FLT ((FLT_TOTAL_BIT + CHAR_BIT - 1) / CHAR_BIT)
#define SIZEOF_DBL ((DBL_TOTAL_BIT + CHAR_BIT - 1) / CHAR_BIT)
#define SIZEOF_LDBL ((LDBL_TOTAL_BIT + CHAR_BIT - 1) / CHAR_BIT)
/* Verify that SIZEOF_FLT <= sizeof (float) etc. */
typedef int verify_sizeof_flt[SIZEOF_FLT <= sizeof (float) ? 1 : -1];
typedef int verify_sizeof_dbl[SIZEOF_DBL <= sizeof (double) ? 1 : - 1];
typedef int verify_sizeof_ldbl[SIZEOF_LDBL <= sizeof (long double) ? 1 : - 1];
#endif /* _FLOATPLUS_H */