1  /* Return arc sine of a complex float type.
       2     Copyright (C) 1997-2018 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4     Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
       5  
       6     The GNU C Library is free software; you can redistribute it and/or
       7     modify it under the terms of the GNU Lesser General Public
       8     License as published by the Free Software Foundation; either
       9     version 2.1 of the License, or (at your option) any later version.
      10  
      11     The GNU C Library is distributed in the hope that it will be useful,
      12     but WITHOUT ANY WARRANTY; without even the implied warranty of
      13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      14     Lesser General Public License for more details.
      15  
      16     You should have received a copy of the GNU Lesser General Public
      17     License along with the GNU C Library; if not, see
      18     <http://www.gnu.org/licenses/>.  */
      19  
      20  #include "quadmath-imp.h"
      21  
      22  __complex128
      23  casinq (__complex128 x)
      24  {
      25    __complex128 res;
      26  
      27    if (isnanq (__real__ x) || isnanq (__imag__ x))
      28      {
      29        if (__real__ x == 0)
      30  	{
      31  	  res = x;
      32  	}
      33        else if (isinfq (__real__ x) || isinfq (__imag__ x))
      34  	{
      35  	  __real__ res = nanq ("");
      36  	  __imag__ res = copysignq (HUGE_VALQ, __imag__ x);
      37  	}
      38        else
      39  	{
      40  	  __real__ res = nanq ("");
      41  	  __imag__ res = nanq ("");
      42  	}
      43      }
      44    else
      45      {
      46        __complex128 y;
      47  
      48        __real__ y = -__imag__ x;
      49        __imag__ y = __real__ x;
      50  
      51        y = casinhq (y);
      52  
      53        __real__ res = __imag__ y;
      54        __imag__ res = -__real__ y;
      55      }
      56  
      57    return res;
      58  }