minix/lib/libm/src/e_scalbf.c

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/* e_scalbf.c -- float version of e_scalb.c.
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
*/
/*
* ====================================================
* 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.
* ====================================================
*/
#include <sys/cdefs.h>
#if defined(LIBM_SCCS) && !defined(lint)
__RCSID("$NetBSD: e_scalbf.c,v 1.7 2010/04/23 19:17:07 drochner Exp $");
#endif
#include "namespace.h"
#include "math.h"
#include "math_private.h"
#ifdef _SCALB_INT
float
__ieee754_scalbf(float x, int fn)
#else
float
__ieee754_scalbf(float x, float fn)
#endif
{
#ifdef _SCALB_INT
return scalbnf(x,fn);
#else
if (isnanf(x)||isnanf(fn)) return x*fn;
if (!finitef(fn)) {
if(fn>(float)0.0) return x*fn;
else return x/(-fn);
}
if (rintf(fn)!=fn) return (fn-fn)/(fn-fn);
if ( fn > (float)65000.0) return scalbnf(x, 65000);
if (-fn > (float)65000.0) return scalbnf(x,-65000);
return scalbnf(x,(int)fn);
#endif
}