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/* @(#)s_isnan.c 5.1 93/09/24 */
/*
* ====================================================
* 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.
* ====================================================
*/
#ifndef lint
static char rcsid[] = "$Id: s_isnan.c,v 1.6 1994/08/18 23:06:54 jtc Exp $";
#endif
/*
* isnan(x) returns 1 is x is nan, else 0;
* no branching!
*/
#include "math.h"
#include "math_private.h"
#ifdef __STDC__
int isnan(double x)
#else
int isnan(x)
double x;
#endif
{
int32_t hx,lx;
EXTRACT_WORDS(hx,lx,x);
hx &= 0x7fffffff;
hx |= (u_int32_t)(lx|(-lx))>>31;
hx = 0x7ff00000 - hx;
return (int)((u_int32_t)(hx))>>31;
}
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