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/* s_copysignl.c -- long double version of s_copysign.c.
* Conversion to long double by Ulrich Drepper,
* Cygnus Support, drepper@cygnus.com.
*/
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
/*
* copysignl(long double x, long double y)
* copysignl(x,y) returns a value with the magnitude of x and
* with the sign bit of y.
*/
#include <endian.h>
#include <stdint.h>
#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 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)
long double copysignl(long double x, long double y);
libc_hidden_proto(copysignl);
long double copysignl(long double x, long double y)
{
uint32_t es1,es2;
GET_LDOUBLE_EXP(es1,x);
GET_LDOUBLE_EXP(es2,y);
SET_LDOUBLE_EXP(x,(es1&0x7fff)|(es2&0x8000));
return x;
}
libc_hidden_def(copysignl);
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