1/* Complex cosine hyperbole function for double.
2 Copyright (C) 1997-2016 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 <complex.h>
21#include <fenv.h>
22#include <math.h>
23#include <math_private.h>
24#include <float.h>
25
26__complex__ double
27__ccosh (__complex__ double x)
28{
29 __complex__ double retval;
30 int rcls = fpclassify (__real__ x);
31 int icls = fpclassify (__imag__ x);
32
33 if (__glibc_likely (rcls >= FP_ZERO))
34 {
35 /* Real part is finite. */
36 if (__glibc_likely (icls >= FP_ZERO))
37 {
38 /* Imaginary part is finite. */
39 const int t = (int) ((DBL_MAX_EXP - 1) * M_LN2);
40 double sinix, cosix;
41
42 if (__glibc_likely (fabs (__imag__ x) > DBL_MIN))
43 {
44 __sincos (__imag__ x, &sinix, &cosix);
45 }
46 else
47 {
48 sinix = __imag__ x;
49 cosix = 1.0;
50 }
51
52 if (fabs (__real__ x) > t)
53 {
54 double exp_t = __ieee754_exp (t);
55 double rx = fabs (__real__ x);
56 if (signbit (__real__ x))
57 sinix = -sinix;
58 rx -= t;
59 sinix *= exp_t / 2.0;
60 cosix *= exp_t / 2.0;
61 if (rx > t)
62 {
63 rx -= t;
64 sinix *= exp_t;
65 cosix *= exp_t;
66 }
67 if (rx > t)
68 {
69 /* Overflow (original real part of x > 3t). */
70 __real__ retval = DBL_MAX * cosix;
71 __imag__ retval = DBL_MAX * sinix;
72 }
73 else
74 {
75 double exp_val = __ieee754_exp (rx);
76 __real__ retval = exp_val * cosix;
77 __imag__ retval = exp_val * sinix;
78 }
79 }
80 else
81 {
82 __real__ retval = __ieee754_cosh (__real__ x) * cosix;
83 __imag__ retval = __ieee754_sinh (__real__ x) * sinix;
84 }
85
86 math_check_force_underflow_complex (retval);
87 }
88 else
89 {
90 __imag__ retval = __real__ x == 0.0 ? 0.0 : __nan ("");
91 __real__ retval = __nan ("") + __nan ("");
92
93 if (icls == FP_INFINITE)
94 feraiseexcept (FE_INVALID);
95 }
96 }
97 else if (rcls == FP_INFINITE)
98 {
99 /* Real part is infinite. */
100 if (__glibc_likely (icls > FP_ZERO))
101 {
102 /* Imaginary part is finite. */
103 double sinix, cosix;
104
105 if (__glibc_likely (fabs (__imag__ x) > DBL_MIN))
106 {
107 __sincos (__imag__ x, &sinix, &cosix);
108 }
109 else
110 {
111 sinix = __imag__ x;
112 cosix = 1.0;
113 }
114
115 __real__ retval = __copysign (HUGE_VAL, cosix);
116 __imag__ retval = (__copysign (HUGE_VAL, sinix)
117 * __copysign (1.0, __real__ x));
118 }
119 else if (icls == FP_ZERO)
120 {
121 /* Imaginary part is 0.0. */
122 __real__ retval = HUGE_VAL;
123 __imag__ retval = __imag__ x * __copysign (1.0, __real__ x);
124 }
125 else
126 {
127 /* The addition raises the invalid exception. */
128 __real__ retval = HUGE_VAL;
129 __imag__ retval = __nan ("") + __nan ("");
130
131 if (icls == FP_INFINITE)
132 feraiseexcept (FE_INVALID);
133 }
134 }
135 else
136 {
137 __real__ retval = __nan ("");
138 __imag__ retval = __imag__ x == 0.0 ? __imag__ x : __nan ("");
139 }
140
141 return retval;
142}
143weak_alias (__ccosh, ccosh)
144#ifdef NO_LONG_DOUBLE
145strong_alias (__ccosh, __ccoshl)
146weak_alias (__ccosh, ccoshl)
147#endif
148