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/* Manipulation of the bit representation of 'long double' quantities.
Copyright (C) 1999-2020 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
<https://www.gnu.org/licenses/>. */
#ifndef _MATH_LDBL_H_
#define _MATH_LDBL_H_ 1
#include <stdint.h>
#include <endian.h>
/* A union which permits us to convert between a long double and
three 32 bit ints. */
#if __FLOAT_WORD_ORDER == __BIG_ENDIAN
typedef union
{
long double value;
struct
{
int sign_exponent:16;
unsigned int empty:16;
uint32_t msw;
uint32_t lsw;
} parts;
} ieee_long_double_shape_type;
#endif
#if __FLOAT_WORD_ORDER == __LITTLE_ENDIAN
typedef union
{
long double value;
struct
{
uint32_t lsw;
uint32_t msw;
int sign_exponent:16;
unsigned int empty:16;
} parts;
} ieee_long_double_shape_type;
#endif
/* Get three 32 bit ints from a double. */
#define GET_LDOUBLE_WORDS(exp,ix0,ix1,d) \
do { \
ieee_long_double_shape_type ew_u; \
ew_u.value = (d); \
(exp) = ew_u.parts.sign_exponent; \
(ix0) = ew_u.parts.msw; \
(ix1) = ew_u.parts.lsw; \
} while (0)
/* Set a double from two 32 bit ints. */
#define SET_LDOUBLE_WORDS(d,exp,ix0,ix1) \
do { \
ieee_long_double_shape_type iw_u; \
iw_u.parts.sign_exponent = (exp); \
iw_u.parts.msw = (ix0); \
iw_u.parts.lsw = (ix1); \
(d) = iw_u.value; \
} while (0)
/* Get the more significant 32 bits of a long double mantissa. */
#define GET_LDOUBLE_MSW(v,d) \
do { \
ieee_long_double_shape_type sh_u; \
sh_u.value = (d); \
(v) = sh_u.parts.msw; \
} while (0)
/* Set the more significant 32 bits of a long double mantissa from an int. */
#define SET_LDOUBLE_MSW(d,v) \
do { \
ieee_long_double_shape_type sh_u; \
sh_u.value = (d); \
sh_u.parts.msw = (v); \
(d) = sh_u.value; \
} while (0)
/* Get int from the exponent of a long double. */
#define GET_LDOUBLE_EXP(exp,d) \
do { \
ieee_long_double_shape_type ge_u; \
ge_u.value = (d); \
(exp) = ge_u.parts.sign_exponent; \
} while (0)
/* Set exponent of a long double from an int. */
#define SET_LDOUBLE_EXP(d,exp) \
do { \
ieee_long_double_shape_type se_u; \
se_u.value = (d); \
se_u.parts.sign_exponent = (exp); \
(d) = se_u.value; \
} while (0)
#endif /* math_ldbl.h */
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