15.1.250. tablet_qt/maths/ieee754.h

/* 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 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 _IEEE754_H

#define _IEEE754_H 1
#include <endian.h>
#include <features.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 */