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
15 static 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
28 double
__ieee754_scalb(double x,int fn)29 __ieee754_scalb(double x, int fn)
30 #else
31 double
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