1/* origin: FreeBSD /usr/src/lib/msun/src/e_scalbf.c */
2/*
3 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
4 */
5/*
6 * ====================================================
7 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
8 *
9 * Developed at SunPro, a Sun Microsystems, Inc. business.
10 * Permission to use, copy, modify, and distribute this
11 * software is freely granted, provided that this notice
12 * is preserved.
13 * ====================================================
14 */
15
16#define _GNU_SOURCE
17#include <math.h>
18
19float scalbf(float x, float fn) {
20    if (isnan(x) || isnan(fn))
21        return x * fn;
22    if (!isfinite(fn)) {
23        if (fn > 0.0f)
24            return x * fn;
25        else
26            return x / (-fn);
27    }
28    if (rintf(fn) != fn)
29        return (fn - fn) / (fn - fn);
30    if (fn > 65000.0f)
31        return scalbnf(x, 65000);
32    if (-fn > 65000.0f)
33        return scalbnf(x, -65000);
34    return scalbnf(x, (int)fn);
35}
36