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/* s_asinhl.c -- long double version of s_asinh.c.

 * Conversion to long double by Ulrich Drepper,

 * Cygnus Support, drepper@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.

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

 */

/* asinhl(x)

 * Method :

 *      Based on

 *              asinhl(x) = signl(x) * logl [ |x| + sqrtl(x*x+1) ]

 *      we have

 *      asinhl(x) := x  if  1+x*x=1,

 *                := signl(x)*(logl(x)+ln2)) for large |x|, else

 *                := signl(x)*logl(2|x|+1/(|x|+sqrtl(x*x+1))) if|x|>2, else

 *                := signl(x)*log1pl(|x| + x^2/(1 + sqrtl(1+x^2)))

 */

#include "quadmath-imp.h"

static const __float128

  one = 1.0Q,

  ln2 = 6.931471805599453094172321214581765681e-1Q,

  huge = 1.0e+4900Q;

__float128

asinhq (__float128 x)

{

  __float128 t, w;

  int32_t ix, sign;

  ieee854_float128 u;

  u.value = x;

  sign = u.words32.w0;

  ix = sign & 0x7fffffff;

  if (ix == 0x7fff0000)

    return x + x;               /* x is inf or NaN */

  if (ix < 0x3fc70000)

    {                           /* |x| < 2^ -56 */

      if (huge + x > one)

        return x;               /* return x inexact except 0 */

    }

  u.words32.w0 = ix;

  if (ix > 0x40350000)

    {                           /* |x| > 2 ^ 54 */

      w = logq (u.value) + ln2;

    }

  else if (ix >0x40000000)

    {                           /* 2^ 54 > |x| > 2.0 */

      t = u.value;

      w = logq (2.0 * t + one / (sqrtq (x * x + one) + t));

    }

  else

    {                           /* 2.0 > |x| > 2 ^ -56 */

      t = x * x;

      w = log1pq (u.value + t / (one + sqrtq (one + t)));

    }

  if (sign & 0x80000000)

    return -w;

  else

    return w;

}