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/* ef_sinh.c -- float version of e_sinh.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.

 * ====================================================

 */

#include "fdlibm.h"

#ifdef __STDC__

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

#else

static float one = 1.0, shuge = 1.0e37;

#endif

#ifdef __STDC__

        float __ieee754_sinhf(float x)

#else

        float __ieee754_sinhf(x)

        float x;

#endif

{

        float t,w,h;

        __int32_t ix,jx;

        GET_FLOAT_WORD(jx,x);

        ix = jx&0x7fffffff;

    /* x is INF or NaN */

        if(!FLT_UWORD_IS_FINITE(ix)) 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<=FLT_UWORD_LOG_MAX)  return h*__ieee754_expf(fabsf(x));

    /* |x| in [log(maxdouble), overflowthresold] */

        if (ix<=FLT_UWORD_LOG_2MAX) {

            w = __ieee754_expf((float)0.5*fabsf(x));

            t = h*w;

            return t*w;

        }

    /* |x| > overflowthresold, sinh(x) overflow */

        return x*shuge;

}