/home/jaouen/pok_official/pok/trunk/libpok/libm/isnan.c

/*
 *                               POK header
 * 
 * The following file is a part of the POK project. Any modification should
 * made according to the POK licence. You CANNOT use this file or a part of
 * this file is this part of a file for your own project
 *
 * For more information on the POK licence, please see our LICENCE FILE
 *
 * Please follow the coding guidelines described in doc/CODING_GUIDELINES
 *
 *                                      Copyright (c) 2007-2009 POK team 
 *
 * Created by julien on Fri Jan 30 13:44:27 2009 
 */

/* @(#)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.
 * ====================================================
 */

/*
 * isnan(x) returns 1 is x is nan, else 0;
 * no branching!
 */

#ifdef POK_NEEDS_LIBMATH
#include <types.h>
#include "math_private.h"

int
isnan(double 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;
}
#endif