copysign.c
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#include <ansidecl.h>
#ifdef __IEEE_BIG_ENDIAN
typedef union
{
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
{
unsigned long msw;
unsigned long lsw;
} parts;
long aslong[2];
} __ieee_double_shape_type;
#endif
#ifdef __IEEE_LITTLE_ENDIAN
typedef union
{
double value;
struct
{
#ifdef __SMALL_BITFIELDS
unsigned int fraction3:16;
unsigned int fraction2:16;
unsigned int fraction1:16;
unsigned int fraction0: 4;
#else
unsigned int fraction1:32;
unsigned int fraction0:20;
#endif
unsigned int exponent :11;
unsigned int sign : 1;
} number;
struct
{
#ifdef __SMALL_BITFIELDS
unsigned int function3:16;
unsigned int function2:16;
unsigned int function1:16;
unsigned int function0:3;
#else
unsigned int function1:32;
unsigned int function0:19;
#endif
unsigned int quiet:1;
unsigned int exponent: 11;
unsigned int sign : 1;
} nan;
struct
{
unsigned long lsw;
unsigned long msw;
} parts;
long aslong[2];
} __ieee_double_shape_type;
#endif
#ifdef __IEEE_BIG_ENDIAN
typedef union
{
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;
long p1;
} __ieee_float_shape_type;
#endif
#ifdef __IEEE_LITTLE_ENDIAN
typedef union
{
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;
long p1;
} __ieee_float_shape_type;
#endif
#if defined(__IEEE_BIG_ENDIAN) || defined(__IEEE_LITTLE_ENDIAN)
double
copysign (x, y)
double x, y;
{
__ieee_double_shape_type a,b;
b.value = y;
a.value = x;
a.number.sign =b.number.sign;
return a.value;
}
#else
double
copysign (x, y)
double x, y;
{
if ((x < 0 && y > 0) || (x > 0 && y < 0))
return -x;
return x;
}
#endif