adtools/clib2

/*
 * $Id: math_sinhf.c,v 1.3 2006-01-08 12:04:24 obarthel Exp $
 *
 * :ts=4
 *
 * Portable ISO 'C' (1994) runtime library for the Amiga computer
 * Copyright (c) 2002-2015 by Olaf Barthel <obarthel (at) gmx.net>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Neither the name of Olaf Barthel nor the names of contributors
 *     may be used to endorse or promote products derived from this
 *     software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 *
 * PowerPC math library based in part on work by Sun Microsystems
 * 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.
 *
 *
 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
 */

#ifndef _MATH_HEADERS_H
#include "math_headers.h"
#endif /* _MATH_HEADERS_H */

/****************************************************************************/

#if defined(FLOATING_POINT_SUPPORT)

/****************************************************************************/

static const float one = 1.0, shuge = 1.0e37;

float
sinhf(float x)
{    
    float t,w,h;
    LONG ix,jx;

    GET_FLOAT_WORD(jx,x);
    ix = jx&0x7fffffff;

    /* x is INF or NaN */
    if(ix>=0x7f800000) return x+x;    

    h = 0.5;
    if (jx<0) h = -h;
    /* |x| in [0,22], return sign(x)*0.5*(E+E/(E+1))) */
    if (ix < 0x41b00000) {        /* |x|<22 */
        if (ix<0x31800000)         /* |x|<2**-28 */
        if(shuge+x>one) return x;/* sinh(tiny) = tiny with inexact */
        t = expm1f(fabsf(x));
        if(ix<0x3f800000) return h*((float)2.0*t-t*t/(t+one));
        return h*(t+t/(t+one));
    }

    /* |x| in [22, log(maxdouble)] return 0.5*exp(|x|) */
    if (ix < 0x42b17180)  return h*expf(fabsf(x));

    /* |x| in [log(maxdouble), overflowthresold] */
    if (ix<=0x42b2d4fc) {
        w = expf((float)0.5*fabsf(x));
        t = h*w;
        return t*w;
    }

    /* |x| > overflowthresold, sinh(x) overflow */
    return x*shuge;
}

/****************************************************************************/

#endif /* FLOATING_POINT_SUPPORT */