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/* @(#)e_scalb.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.
* ====================================================
*/
#if defined(LIBM_SCCS) && !defined(lint)
static char rcsid[] = "$NetBSD: e_scalb.c,v 1.6 1995/05/10 20:46:09 jtc Exp $";
#endif
/*
* __ieee754_scalb(x, fn) is provide for
* passing various standard test suite. One
* should use scalbn() instead.
*/
#include <fenv.h>
#include "math.h"
#include "math_private.h"
#ifdef _SCALB_INT
#ifdef __STDC__
double __ieee754_scalb(double x, int fn)
#else
double __ieee754_scalb(x,fn)
double x; int fn;
#endif
#else
#ifdef __STDC__
double __ieee754_scalb(double x, double fn)
#else
double __ieee754_scalb(x,fn)
double x, fn;
#endif
#endif
{
#ifdef _SCALB_INT
return __scalbn(x,fn);
#else
if (__isnan(x)||__isnan(fn)) return x*fn;
if (!__finite(fn)) {
if(fn>0.0) return x*fn;
else if (x == 0)
return x;
else if (!__finite (x))
{
# ifdef FE_INVALID
feraiseexcept (FE_INVALID);
# endif
return __nan ("");
}
else return x/(-fn);
}
if (__rint(fn)!=fn)
{
# ifdef FE_INVALID
feraiseexcept (FE_INVALID);
# endif
return __nan ("");
}
if ( fn > 65000.0) return __scalbn(x, 65000);
if (-fn > 65000.0) return __scalbn(x,-65000);
return __scalbn(x,(int)fn);
#endif
}
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