summary refs log tree commit diff
path: root/math/s_ccosh.c
blob: 91477ee2d0e8668032304d5f607f305b4f212324 (plain) (blame)
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
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
/* Complex cosine hyperbole function for double.
   Copyright (C) 1997-2012 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 <fenv.h>
#include <math.h>
#include <math_private.h>
#include <float.h>

__complex__ double
__ccosh (__complex__ double x)
{
  __complex__ double retval;
  int rcls = fpclassify (__real__ x);
  int icls = fpclassify (__imag__ x);

  if (__builtin_expect (rcls >= FP_ZERO, 1))
    {
      /* Real part is finite.  */
      if (__builtin_expect (icls >= FP_ZERO, 1))
	{
	  /* Imaginary part is finite.  */
	  const int t = (int) ((DBL_MAX_EXP - 1) * M_LN2);
	  double sinix, cosix;

	  if (__builtin_expect (icls != FP_SUBNORMAL, 1))
	    {
	      __sincos (__imag__ x, &sinix, &cosix);
	    }
	  else
	    {
	      sinix = __imag__ x;
	      cosix = 1.0;
	    }

	  if (fabs (__real__ x) > t)
	    {
	      double exp_t = __ieee754_exp (t);
	      double rx = fabs (__real__ x);
	      if (signbit (__real__ x))
		sinix = -sinix;
	      rx -= t;
	      sinix *= exp_t / 2.0;
	      cosix *= exp_t / 2.0;
	      if (rx > t)
		{
		  rx -= t;
		  sinix *= exp_t;
		  cosix *= exp_t;
		}
	      if (rx > t)
		{
		  /* Overflow (original real part of x > 3t).  */
		  __real__ retval = DBL_MAX * cosix;
		  __imag__ retval = DBL_MAX * sinix;
		}
	      else
		{
		  double exp_val = __ieee754_exp (rx);
		  __real__ retval = exp_val * cosix;
		  __imag__ retval = exp_val * sinix;
		}
	    }
	  else
	    {
	      __real__ retval = __ieee754_cosh (__real__ x) * cosix;
	      __imag__ retval = __ieee754_sinh (__real__ x) * sinix;
	    }
	}
      else
	{
	  __imag__ retval = __real__ x == 0.0 ? 0.0 : __nan ("");
	  __real__ retval = __nan ("") + __nan ("");

	  if (icls == FP_INFINITE)
	    feraiseexcept (FE_INVALID);
	}
    }
  else if (rcls == FP_INFINITE)
    {
      /* Real part is infinite.  */
      if (__builtin_expect (icls > FP_ZERO, 1))
	{
	  /* Imaginary part is finite.  */
	  double sinix, cosix;

	  if (__builtin_expect (icls != FP_SUBNORMAL, 1))
	    {
	      __sincos (__imag__ x, &sinix, &cosix);
	    }
	  else
	    {
	      sinix = __imag__ x;
	      cosix = 1.0;
	    }

	  __real__ retval = __copysign (HUGE_VAL, cosix);
	  __imag__ retval = (__copysign (HUGE_VAL, sinix)
			     * __copysign (1.0, __real__ x));
	}
      else if (icls == FP_ZERO)
	{
	  /* Imaginary part is 0.0.  */
	  __real__ retval = HUGE_VAL;
	  __imag__ retval = __imag__ x * __copysign (1.0, __real__ x);
	}
      else
	{
	  /* The addition raises the invalid exception.  */
	  __real__ retval = HUGE_VAL;
	  __imag__ retval = __nan ("") + __nan ("");

	  if (icls == FP_INFINITE)
	    feraiseexcept (FE_INVALID);
	}
    }
  else
    {
      __real__ retval = __nan ("");
      __imag__ retval = __imag__ x == 0.0 ? __imag__ x : __nan ("");
    }

  return retval;
}
weak_alias (__ccosh, ccosh)
#ifdef NO_LONG_DOUBLE
strong_alias (__ccosh, __ccoshl)
weak_alias (__ccosh, ccoshl)
#endif