1
2/* @(#)e_scalb.c 1.3 95/01/18 */
3/*
4 * ====================================================
5 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
6 *
7 * Developed at SunSoft, a Sun Microsystems, Inc. business.
8 * Permission to use, copy, modify, and distribute this
9 * software is freely granted, provided that this notice
10 * is preserved.
11 * ====================================================
12 */
13
14#ifndef lint
15static char rcsid[] = "$FreeBSD: src/lib/msun/src/e_scalb.c,v 1.12 2005/02/04 18:26:06 das Exp $";
16#endif
17
18/*
19 * __ieee754_scalb(x, fn) is provide for
20 * passing various standard test suite. One
21 * should use scalbn() instead.
22 */
23
24#include "math.h"
25#include "math_private.h"
26
27#ifdef _SCALB_INT
28double
29__ieee754_scalb(double x, int fn)
30#else
31double
32__ieee754_scalb(double x, double fn)
33#endif
34{
35#ifdef _SCALB_INT
36	return scalbn(x,fn);
37#else
38	if (isnan(x)||isnan(fn)) return x*fn;
39	if (!finite(fn)) {
40	    if(fn>0.0) return x*fn;
41	    else       return x/(-fn);
42	}
43	if (rint(fn)!=fn) return (fn-fn)/(fn-fn);
44	if ( fn > 65000.0) return scalbn(x, 65000);
45	if (-fn > 65000.0) return scalbn(x,-65000);
46	return scalbn(x,(int)fn);
47#endif
48}
49