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/* 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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#ifndef SCM_IEEE_754_H
#define SCM_IEEE_754_H 1
/* Based on glibc's <ieee754.h> and modified by Ludovic Courtès to include
all possible IEEE-754 double-precision representations. */
/* IEEE 754 simple-precision format (32-bit). */
union scm_ieee754_float
{
float f;
struct
{
unsigned int negative:1;
unsigned int exponent:8;
unsigned int mantissa:23;
} big_endian;
struct
{
unsigned int mantissa:23;
unsigned int exponent:8;
unsigned int negative:1;
} little_endian;
};
/* IEEE 754 double-precision format (64-bit). */
union scm_ieee754_double
{
double d;
struct
{
/* Big endian. */
unsigned int negative:1;
unsigned int exponent:11;
/* Together these comprise the mantissa. */
unsigned int mantissa0:20;
unsigned int mantissa1:32;
} big_endian;
struct
{
/* Both byte order and word order are little endian. */
/* Together these comprise the mantissa. */
unsigned int mantissa1:32;
unsigned int mantissa0:20;
unsigned int exponent:11;
unsigned int negative:1;
} little_little_endian;
struct
{
/* Byte order is little endian but word order is big endian. Not
sure this is very wide spread. */
unsigned int mantissa0:20;
unsigned int exponent:11;
unsigned int negative:1;
unsigned int mantissa1:32;
} little_big_endian;
};
#endif /* SCM_IEEE_754_H */
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