glibc/stdlib/fpioconst.h
2012-02-09 23:18:22 +00:00

69 lines
2.3 KiB
C

/* Header file for constants used in floating point <-> decimal conversions.
Copyright (C) 1995, 1996, 1997, 1998, 1999, 2002, 2003
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
<http://www.gnu.org/licenses/>. */
#ifndef _FPIOCONST_H
#define _FPIOCONST_H
#include <float.h>
#include <math.h>
#include <gmp.h>
/* These values are used by __printf_fp, where they are noncritical (if the
value is not large enough, it will just be slower); and by
strtof/strtod/strtold, where it is critical (it's used for overflow
detection).
XXX These should be defined in <float.h>. For the time being, we have the
IEEE754 values here. */
#if !defined __NO_LONG_DOUBLE_MATH && __LDBL_MAX_EXP__ > 1024
# define LDBL_MAX_10_EXP_LOG 12 /* = floor(log_2(LDBL_MAX_10_EXP)) */
#else
# define LDBL_MAX_10_EXP_LOG 8 /* = floor(log_2(LDBL_MAX_10_EXP)) */
#endif
#define DBL_MAX_10_EXP_LOG 8 /* = floor(log_2(DBL_MAX_10_EXP)) */
#define FLT_MAX_10_EXP_LOG 5 /* = floor(log_2(FLT_MAX_10_EXP)) */
/* The array with the number representation. */
extern const mp_limb_t __tens[] attribute_hidden;
/* Table of powers of ten. This is used by __printf_fp and by
strtof/strtod/strtold. */
struct mp_power
{
size_t arrayoff; /* Offset in `__tens'. */
mp_size_t arraysize; /* Size of the array. */
int p_expo; /* Exponent of the number 10^(2^i). */
int m_expo; /* Exponent of the number 10^-(2^i-1). */
};
extern const struct mp_power _fpioconst_pow10[LDBL_MAX_10_EXP_LOG + 1]
attribute_hidden;
/* The constants in the array `_fpioconst_pow10' have an offset. */
#if BITS_PER_MP_LIMB == 32
# define _FPIO_CONST_OFFSET 2
#else
# define _FPIO_CONST_OFFSET 1
#endif
#endif /* fpioconst.h */