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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.
* ====================================================
*/
/*
* __ieee754_scalb(x, fn) is provided for
* passing various standard test suites.
* One should use scalbn() instead.
*/
#include "math.h"
#include "math_private.h"
#include <errno.h>
double __ieee754_scalb(double x, double fn)
{
if (isnan(x)||isnan(fn)) return x*fn;
if (!isfinite(fn)) {
if(fn>0.0) return x*fn;
else return x/(-fn);
}
if (rint(fn)!=fn) return (fn-fn)/(fn-fn);
if ( fn > 65000.0) return scalbn(x, 65000);
if (-fn > 65000.0) return scalbn(x,-65000);
return scalbn(x,(int)fn);
}
#if defined __UCLIBC_SUSV3_LEGACY__
/*
* wrapper scalb(double x, double fn) is provided for
* passing various standard test suites.
* One should use scalbn() instead.
*/
#ifndef _IEEE_LIBM
double scalb(double x, double fn)
{
double z = __ieee754_scalb(x, fn);
if (_LIB_VERSION == _IEEE_)
return z;
if (!(isfinite(z) || isnan(z)) && isfinite(x))
return __kernel_standard(x, (double)fn, 32); /* scalb overflow */
if (z == 0.0 && z != x)
return __kernel_standard(x, (double)fn, 33); /* scalb underflow */
if (!isfinite(fn))
errno = ERANGE;
return z;
}
#else
strong_alias(__ieee754_scalb, scalb)
#endif
libm_hidden_def(scalb)
#endif /* UCLIBC_SUSV3_LEGACY */
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