1/* Complex cosine hyperbolic function for float types.
2 Copyright (C) 1997-2020 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 <https://www.gnu.org/licenses/>. */
19
20#include <complex.h>
21#include <fenv.h>
22#include <math.h>
23#include <math_private.h>
24#include <math-underflow.h>
25#include <float.h>
26
27CFLOAT
28M_DECL_FUNC (__ccosh) (CFLOAT x)
29{
30 CFLOAT retval;
31 int rcls = fpclassify (__real__ x);
32 int icls = fpclassify (__imag__ x);
33
34 if (__glibc_likely (rcls >= FP_ZERO))
35 {
36 /* Real part is finite. */
37 if (__glibc_likely (icls >= FP_ZERO))
38 {
39 /* Imaginary part is finite. */
40 const int t = (int) ((M_MAX_EXP - 1) * M_MLIT (M_LN2));
41 FLOAT sinix, cosix;
42
43 if (__glibc_likely (M_FABS (__imag__ x) > M_MIN))
44 {
45 M_SINCOS (__imag__ x, &sinix, &cosix);
46 }
47 else
48 {
49 sinix = __imag__ x;
50 cosix = 1;
51 }
52
53 if (M_FABS (__real__ x) > t)
54 {
55 FLOAT exp_t = M_EXP (t);
56 FLOAT rx = M_FABS (__real__ x);
57 if (signbit (__real__ x))
58 sinix = -sinix;
59 rx -= t;
60 sinix *= exp_t / 2;
61 cosix *= exp_t / 2;
62 if (rx > t)
63 {
64 rx -= t;
65 sinix *= exp_t;
66 cosix *= exp_t;
67 }
68 if (rx > t)
69 {
70 /* Overflow (original real part of x > 3t). */
71 __real__ retval = M_MAX * cosix;
72 __imag__ retval = M_MAX * sinix;
73 }
74 else
75 {
76 FLOAT exp_val = M_EXP (rx);
77 __real__ retval = exp_val * cosix;
78 __imag__ retval = exp_val * sinix;
79 }
80 }
81 else
82 {
83 __real__ retval = M_COSH (__real__ x) * cosix;
84 __imag__ retval = M_SINH (__real__ x) * sinix;
85 }
86
87 math_check_force_underflow_complex (retval);
88 }
89 else
90 {
91 __imag__ retval = __real__ x == 0 ? 0 : M_NAN;
92 __real__ retval = __imag__ x - __imag__ x;
93 }
94 }
95 else if (rcls == FP_INFINITE)
96 {
97 /* Real part is infinite. */
98 if (__glibc_likely (icls > FP_ZERO))
99 {
100 /* Imaginary part is finite. */
101 FLOAT sinix, cosix;
102
103 if (__glibc_likely (M_FABS (__imag__ x) > M_MIN))
104 {
105 M_SINCOS (__imag__ x, &sinix, &cosix);
106 }
107 else
108 {
109 sinix = __imag__ x;
110 cosix = 1;
111 }
112
113 __real__ retval = M_COPYSIGN (M_HUGE_VAL, cosix);
114 __imag__ retval = (M_COPYSIGN (M_HUGE_VAL, sinix)
115 * M_COPYSIGN (1, __real__ x));
116 }
117 else if (icls == FP_ZERO)
118 {
119 /* Imaginary part is 0.0. */
120 __real__ retval = M_HUGE_VAL;
121 __imag__ retval = __imag__ x * M_COPYSIGN (1, __real__ x);
122 }
123 else
124 {
125 __real__ retval = M_HUGE_VAL;
126 __imag__ retval = __imag__ x - __imag__ x;
127 }
128 }
129 else
130 {
131 __real__ retval = M_NAN;
132 __imag__ retval = __imag__ x == 0 ? __imag__ x : M_NAN;
133 }
134
135 return retval;
136}
137
138declare_mgen_alias (__ccosh, ccosh);
139