📄 ieeefp.h
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#ifndef CYGONCE_LIBM_SYS_IEEEFP_H
#define CYGONCE_LIBM_SYS_IEEEFP_H
//===========================================================================
//
// ieeefp.h
//
// Definitions specific to IEEE-754 floating-point format
//
//===========================================================================
//####ECOSGPLCOPYRIGHTBEGIN####
// -------------------------------------------
// This file is part of eCos, the Embedded Configurable Operating System.
// Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
//
// eCos 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 2 or (at your option) any later version.
//
// eCos 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 eCos; if not, write to the Free Software Foundation, Inc.,
// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
//
// As a special exception, if other files instantiate templates or use macros
// or inline functions from this file, or you compile this file and link it
// with other works to produce a work based on this file, this file does not
// by itself cause the resulting work to be covered by the GNU General Public
// License. However the source code for this file must still be made available
// in accordance with section (3) of the GNU General Public License.
//
// This exception does not invalidate any other reasons why a work based on
// this file might be covered by the GNU General Public License.
//
// Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.
// at http://sources.redhat.com/ecos/ecos-license/
// -------------------------------------------
//####ECOSGPLCOPYRIGHTEND####
//===========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s): jlarmour
// Contributors: jlarmour
// Date: 1998-02-13
// Purpose:
// Description: Definitions specific to IEEE-754 floating-point format
// Usage: #include <sys/ieeefp.h>
//
//####DESCRIPTIONEND####
//
//===========================================================================
// CONFIGURATION
#include <pkgconf/libm.h> // Configuration header
// Include the Math library?
#ifdef CYGPKG_LIBM
// INCLUDES
#include <cyg/infra/cyg_type.h> // Common type definitions and support
// including endian-ness
#if (CYG_BYTEORDER == CYG_MSBFIRST) // Big endian
// Note: there do not seem to be any current machines which are Big Endian but
// have a mixed up double layout.
typedef union
{
cyg_int32 asi32[2];
cyg_int64 asi64;
double value;
struct
{
unsigned int sign : 1;
unsigned int exponent: 11;
unsigned int fraction0:4;
unsigned int fraction1:16;
unsigned int fraction2:16;
unsigned int fraction3:16;
} number;
struct
{
unsigned int sign : 1;
unsigned int exponent: 11;
unsigned int quiet:1;
unsigned int function0:3;
unsigned int function1:16;
unsigned int function2:16;
unsigned int function3:16;
} nan;
struct
{
cyg_uint32 msw;
cyg_uint32 lsw;
} parts;
} Cyg_libm_ieee_double_shape_type;
typedef union
{
cyg_int32 asi32;
float value;
struct
{
unsigned int sign : 1;
unsigned int exponent: 8;
unsigned int fraction0: 7;
unsigned int fraction1: 16;
} number;
struct
{
unsigned int sign:1;
unsigned int exponent:8;
unsigned int quiet:1;
unsigned int function0:6;
unsigned int function1:16;
} nan;
} Cyg_libm_ieee_float_shape_type;
#else // Little endian
typedef union
{
cyg_int32 asi32[2];
cyg_int64 asi64;
double value;
struct
{
#if (CYG_DOUBLE_BYTEORDER == CYG_MSBFIRST) // Big endian
unsigned int fraction1:16;
unsigned int fraction0: 4;
unsigned int exponent :11;
unsigned int sign : 1;
unsigned int fraction3:16;
unsigned int fraction2:16;
#else
unsigned int fraction3:16;
unsigned int fraction2:16;
unsigned int fraction1:16;
unsigned int fraction0: 4;
unsigned int exponent :11;
unsigned int sign : 1;
#endif
} number;
struct
{
#if (CYG_DOUBLE_BYTEORDER == CYG_MSBFIRST) // Big endian
unsigned int function1:16;
unsigned int function0:3;
unsigned int quiet:1;
unsigned int exponent: 11;
unsigned int sign : 1;
unsigned int function3:16;
unsigned int function2:16;
#else
unsigned int function3:16;
unsigned int function2:16;
unsigned int function1:16;
unsigned int function0:3;
unsigned int quiet:1;
unsigned int exponent: 11;
unsigned int sign : 1;
#endif
} nan;
struct
{
#if (CYG_DOUBLE_BYTEORDER == CYG_MSBFIRST) // Big endian
cyg_uint32 msw;
cyg_uint32 lsw;
#else
cyg_uint32 lsw;
cyg_uint32 msw;
#endif
} parts;
} Cyg_libm_ieee_double_shape_type;
typedef union
{
cyg_int32 asi32;
float value;
struct
{
unsigned int fraction0: 7;
unsigned int fraction1: 16;
unsigned int exponent: 8;
unsigned int sign : 1;
} number;
struct
{
unsigned int function1:16;
unsigned int function0:6;
unsigned int quiet:1;
unsigned int exponent:8;
unsigned int sign:1;
} nan;
} Cyg_libm_ieee_float_shape_type;
#endif // little-endian
#endif // ifdef CYGPKG_LIBM
#endif // CYGONCE_LIBM_SYS_IEEEFP_H multiple inclusion protection
// EOF ieeefp.h
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