/* origin: FreeBSD /usr/src/lib/msun/src/e_scalbf.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.
 * ====================================================
 */

#define _GNU_SOURCE
#include <math.h>

float scalbf(float x, float fn) {
    if (isnan(x) || isnan(fn))
        return x * fn;
    if (!isfinite(fn)) {
        if (fn > 0.0f)
            return x * fn;
        else
            return x / (-fn);
    }
    if (rintf(fn) != fn)
        return (fn - fn) / (fn - fn);
    if (fn > 65000.0f)
        return scalbnf(x, 65000);
    if (-fn > 65000.0f)
        return scalbnf(x, -65000);
    return scalbnf(x, (int)fn);
}