aboutsummaryrefslogtreecommitdiff
path: root/math/s_casinhf.c
blob: e3a92f51133c4bb2e60335dd96af59aab7eb4912 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
/* Return arc hyperbole sine for float value.
   Copyright (C) 1997-2013 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <http://www.gnu.org/licenses/>.  */

#include <complex.h>
#include <math.h>
#include <math_private.h>


__complex__ float
__casinhf (__complex__ float x)
{
  __complex__ float res;
  int rcls = fpclassify (__real__ x);
  int icls = fpclassify (__imag__ x);

  if (rcls <= FP_INFINITE || icls <= FP_INFINITE)
    {
      if (icls == FP_INFINITE)
	{
	  __real__ res = __copysignf (HUGE_VALF, __real__ x);

	  if (rcls == FP_NAN)
	    __imag__ res = __nanf ("");
	  else
	    __imag__ res = __copysignf (rcls >= FP_ZERO ? M_PI_2 : M_PI_4,
					__imag__ x);
	}
      else if (rcls <= FP_INFINITE)
	{
	  __real__ res = __real__ x;
	  if ((rcls == FP_INFINITE && icls >= FP_ZERO)
	      || (rcls == FP_NAN && icls == FP_ZERO))
	    __imag__ res = __copysignf (0.0, __imag__ x);
	  else
	    __imag__ res = __nanf ("");
	}
      else
	{
	  __real__ res = __nanf ("");
	  __imag__ res = __nanf ("");
	}
    }
  else if (rcls == FP_ZERO && icls == FP_ZERO)
    {
      res = x;
    }
  else
    {
      __complex__ float y;

      __real__ y = (__real__ x - __imag__ x) * (__real__ x + __imag__ x) + 1.0;
      __imag__ y = 2.0 * __real__ x * __imag__ x;

      y = __csqrtf (y);

      __real__ y += __real__ x;
      __imag__ y += __imag__ x;

      res = __clogf (y);

      /* Ensure zeros have correct sign and results are correct if
	 very close to branch cuts.  */
      __real__ res = __copysignf (__real__ res, __real__ x);
      __imag__ res = __copysignf (__imag__ res, __imag__ x);
    }

  return res;
}
#ifndef __casinhf
weak_alias (__casinhf, casinhf)
#endif