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/*
* ====================================================
* 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.
* ====================================================
*/
/*
FUNCTION
<<isnan>>, <<isnanf>>, <<isinf>>, <<isinff>>, <<finite>>, <<finitef>>---test for exceptional numbers
INDEX
isnan
INDEX
isinf
INDEX
finite
INDEX
isnanf
INDEX
isinff
INDEX
finitef
SYNOPSIS
#include <math.h>
int isnan(double <[arg]>);
int isinf(double <[arg]>);
int finite(double <[arg]>);
int isnanf(float <[arg]>);
int isinff(float <[arg]>);
int finitef(float <[arg]>);
DESCRIPTION
These functions provide information on the floating-point
argument supplied.
There are five major number formats:
o+
o zero
A number which contains all zero bits.
o subnormal
A number with a zero exponent but a nonzero fraction.
o normal
A number with an exponent and a fraction.
o infinity
A number with an all 1's exponent and a zero fraction.
o NAN
A number with an all 1's exponent and a nonzero fraction.
o-
<<isnan>> returns 1 if the argument is a nan. <<isinf>>
returns 1 if the argument is infinity. <<finite>> returns 1 if the
argument is zero, subnormal or normal.
Note that by the C99 standard, <<isnan>> and <<isinf>> are macros
taking any type of floating-point and are declared in
<<math.h>>. Newlib has chosen to declare these both as functions
and as macros in <<math.h>>.
The <<isnanf>>, <<isinff>> and <<finitef>> functions perform the same
operations as their <<isnan>>, <<isinf>> and <<finite>>
counterparts, but on single-precision floating-point numbers.
QUICKREF
isnan - pure
QUICKREF
isinf - pure
QUICKREF
finite - pure
QUICKREF
isnan - pure
QUICKREF
isinf - pure
QUICKREF
finite - pure
*/
/*
* __isnand(x) returns 1 is x is nan, else 0;
* no branching!
*/
#define __isnan __isnand
#include "fdlibm.h"
#ifdef _NEED_FLOAT64
int
__isnan64 (__float64 x)
{
__int32_t hx,lx;
EXTRACT_WORDS(hx,lx,x);
hx &= 0x7fffffff;
hx |= (__uint32_t)(lx|(-lx))>>31;
hx = 0x7ff00000 - hx;
return (int)(((__uint32_t)(hx))>>31);
}
_MATH_ALIAS_i_d(__isnan)
#endif /* _NEED_FLOAT64 */
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