mirror of
git://sourceware.org/git/glibc.git
synced 2024-11-21 01:12:26 +08:00
918736844a
* sysdeps/ieee754/ieee754.h: Handle platforms with special __FLOAT_WORD_ORDER. Patch by Joel Klecker <jk@espy.org>.
200 lines
4.9 KiB
C
200 lines
4.9 KiB
C
/* Copyright (C) 1992, 1995, 1996, 1999 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 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. */
|
|
|
|
#ifndef _IEEE754_H
|
|
|
|
#define _IEEE754_H 1
|
|
#include <features.h>
|
|
|
|
#include <endian.h>
|
|
|
|
__BEGIN_DECLS
|
|
|
|
union ieee754_float
|
|
{
|
|
float f;
|
|
|
|
/* This is the IEEE 754 single-precision format. */
|
|
struct
|
|
{
|
|
#if __BYTE_ORDER == __BIG_ENDIAN
|
|
unsigned int negative:1;
|
|
unsigned int exponent:8;
|
|
unsigned int mantissa:23;
|
|
#endif /* Big endian. */
|
|
#if __BYTE_ORDER == __LITTLE_ENDIAN
|
|
unsigned int mantissa:23;
|
|
unsigned int exponent:8;
|
|
unsigned int negative:1;
|
|
#endif /* Little endian. */
|
|
} ieee;
|
|
|
|
/* This format makes it easier to see if a NaN is a signalling NaN. */
|
|
struct
|
|
{
|
|
#if __BYTE_ORDER == __BIG_ENDIAN
|
|
unsigned int negative:1;
|
|
unsigned int exponent:8;
|
|
unsigned int quiet_nan:1;
|
|
unsigned int mantissa:22;
|
|
#endif /* Big endian. */
|
|
#if __BYTE_ORDER == __LITTLE_ENDIAN
|
|
unsigned int mantissa:22;
|
|
unsigned int quiet_nan:1;
|
|
unsigned int exponent:8;
|
|
unsigned int negative:1;
|
|
#endif /* Little endian. */
|
|
} ieee_nan;
|
|
};
|
|
|
|
#define IEEE754_FLOAT_BIAS 0x7f /* Added to exponent. */
|
|
|
|
|
|
union ieee754_double
|
|
{
|
|
double d;
|
|
|
|
/* This is the IEEE 754 double-precision format. */
|
|
struct
|
|
{
|
|
#if __BYTE_ORDER == __BIG_ENDIAN
|
|
unsigned int negative:1;
|
|
unsigned int exponent:11;
|
|
/* Together these comprise the mantissa. */
|
|
unsigned int mantissa0:20;
|
|
unsigned int mantissa1:32;
|
|
#endif /* Big endian. */
|
|
#if __BYTE_ORDER == __LITTLE_ENDIAN
|
|
# if __FLOAT_WORD_ORDER == BIG_ENDIAN
|
|
unsigned int mantissa0:20;
|
|
unsigned int exponent:11;
|
|
unsigned int negative:1;
|
|
unsigned int mantissa1:32;
|
|
# else
|
|
/* Together these comprise the mantissa. */
|
|
unsigned int mantissa1:32;
|
|
unsigned int mantissa0:20;
|
|
unsigned int exponent:11;
|
|
unsigned int negative:1;
|
|
# endif
|
|
#endif /* Little endian. */
|
|
} ieee;
|
|
|
|
/* This format makes it easier to see if a NaN is a signalling NaN. */
|
|
struct
|
|
{
|
|
#if __BYTE_ORDER == __BIG_ENDIAN
|
|
unsigned int negative:1;
|
|
unsigned int exponent:11;
|
|
unsigned int quiet_nan:1;
|
|
/* Together these comprise the mantissa. */
|
|
unsigned int mantissa0:19;
|
|
unsigned int mantissa1:32;
|
|
#else
|
|
# if __FLOAT_WORD_ORDER == BIG_ENDIAN
|
|
unsigned int mantissa0:19;
|
|
unsigned int quiet_nan:1;
|
|
unsigned int exponent:11;
|
|
unsigned int negative:1;
|
|
unsigned int mantissa1:32;
|
|
# else
|
|
/* Together these comprise the mantissa. */
|
|
unsigned int mantissa1:32;
|
|
unsigned int mantissa0:19;
|
|
unsigned int quiet_nan:1;
|
|
unsigned int exponent:11;
|
|
unsigned int negative:1;
|
|
# endif
|
|
#endif
|
|
} ieee_nan;
|
|
};
|
|
|
|
#define IEEE754_DOUBLE_BIAS 0x3ff /* Added to exponent. */
|
|
|
|
|
|
union ieee854_long_double
|
|
{
|
|
long double d;
|
|
|
|
/* This is the IEEE 854 double-extended-precision format. */
|
|
struct
|
|
{
|
|
#if __BYTE_ORDER == __BIG_ENDIAN
|
|
unsigned int negative:1;
|
|
unsigned int exponent:15;
|
|
unsigned int empty:16;
|
|
unsigned int mantissa0:32;
|
|
unsigned int mantissa1:32;
|
|
#endif
|
|
#if __BYTE_ORDER == __LITTLE_ENDIAN
|
|
# if __FLOAT_WORD_ORDER == BIG_ENDIAN
|
|
unsigned int exponent:15;
|
|
unsigned int negative:1;
|
|
unsigned int empty:16;
|
|
unsigned int mantissa0:32;
|
|
unsigned int mantissa1:32;
|
|
# else
|
|
unsigned int mantissa1:32;
|
|
unsigned int mantissa0:32;
|
|
unsigned int exponent:15;
|
|
unsigned int negative:1;
|
|
unsigned int empty:16;
|
|
# endif
|
|
#endif
|
|
} ieee;
|
|
|
|
/* This is for NaNs in the IEEE 854 double-extended-precision format. */
|
|
struct
|
|
{
|
|
#if __BYTE_ORDER == __BIG_ENDIAN
|
|
unsigned int negative:1;
|
|
unsigned int exponent:15;
|
|
unsigned int empty:16;
|
|
unsigned int one:1;
|
|
unsigned int quiet_nan:1;
|
|
unsigned int mantissa0:30;
|
|
unsigned int mantissa1:32;
|
|
#endif
|
|
#if __BYTE_ORDER == __LITTLE_ENDIAN
|
|
# if __FLOAT_WORD_ORDER == BIG_ENDIAN
|
|
unsigned int exponent:15;
|
|
unsigned int negative:1;
|
|
unsigned int empty:16;
|
|
unsigned int mantissa0:30;
|
|
unsigned int quiet_nan:1;
|
|
unsigned int one:1;
|
|
unsigned int mantissa1:32;
|
|
# else
|
|
unsigned int mantissa1:32;
|
|
unsigned int mantissa0:30;
|
|
unsigned int quiet_nan:1;
|
|
unsigned int one:1;
|
|
unsigned int exponent:15;
|
|
unsigned int negative:1;
|
|
unsigned int empty:16;
|
|
# endif
|
|
#endif
|
|
} ieee_nan;
|
|
};
|
|
|
|
#define IEEE854_LONG_DOUBLE_BIAS 0x3fff
|
|
|
|
__END_DECLS
|
|
|
|
#endif /* ieee754.h */
|