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/* @(#)w_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.
* ====================================================
*/
/*
* wrapper scalb(double x, double fn) is provide for
* passing various standard test suite. One
* should use scalbn() instead.
*/
#include "fdlibm.h"
#include <errno.h>
#ifndef _DOUBLE_IS_32BITS
#if !defined(_IEEE_LIBM) || !defined(HAVE_ALIAS_ATTRIBUTE)
#ifdef __STDC__
#ifdef _SCALB_INT
double scalb(double x, int fn) /* wrapper scalb */
#else
double scalb(double x, double fn) /* wrapper scalb */
#endif
#else
double scalb(x,fn) /* wrapper scalb */
#ifdef _SCALB_INT
double x; int fn;
#else
double x,fn;
#endif
#endif
{
double z;
z = __ieee754_scalb(x,fn);
if(_LIB_VERSION == _IEEE_) return z;
if(!(finite(z)||isnan(z))&&finite(x)) {
/* scalb overflow */
errno = ERANGE;
return (x > 0.0 ? HUGE_VAL : -HUGE_VAL);
}
if(z==0.0&&z!=x) {
/* scalb underflow */
errno = ERANGE;
return copysign(0.0,x);
}
#ifndef _SCALB_INT
if(!finite(fn)) errno = ERANGE;
#endif
return z;
}
#endif
#endif /* defined(_DOUBLE_IS_32BITS) */
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