1/* Return arc hyperbolic cosine for a complex type.
2 Copyright (C) 1997-2024 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#include <complex.h>
20#include <math.h>
21
22
23CFLOAT
24M_DECL_FUNC (__cacosh) (CFLOAT x)
25{
26 CFLOAT res;
27 int rcls = fpclassify (__real__ x);
28 int icls = fpclassify (__imag__ x);
29
30 if (rcls <= FP_INFINITE || icls <= FP_INFINITE)
31 {
32 if (icls == FP_INFINITE)
33 {
34 __real__ res = M_HUGE_VAL;
35
36 if (rcls == FP_NAN)
37 __imag__ res = M_NAN;
38 else
39 __imag__ res = M_COPYSIGN ((rcls == FP_INFINITE
40 ? (__real__ x < 0
41 ? M_MLIT (M_PI) - M_MLIT (M_PI_4)
42 : M_MLIT (M_PI_4))
43 : M_MLIT (M_PI_2)), __imag__ x);
44 }
45 else if (rcls == FP_INFINITE)
46 {
47 __real__ res = M_HUGE_VAL;
48
49 if (icls >= FP_ZERO)
50 __imag__ res = M_COPYSIGN (signbit (__real__ x)
51 ? M_MLIT (M_PI) : 0, __imag__ x);
52 else
53 __imag__ res = M_NAN;
54 }
55 else
56 {
57 __real__ res = M_NAN;
58 if (rcls == FP_ZERO)
59 __imag__ res = M_MLIT (M_PI_2);
60 else
61 __imag__ res = M_NAN;
62 }
63 }
64 else if (rcls == FP_ZERO && icls == FP_ZERO)
65 {
66 __real__ res = 0;
67 __imag__ res = M_COPYSIGN (M_MLIT (M_PI_2), __imag__ x);
68 }
69 else
70 {
71 CFLOAT y;
72
73 __real__ y = -__imag__ x;
74 __imag__ y = __real__ x;
75
76 y = M_SUF (__kernel_casinh) (y, 1);
77
78 if (signbit (__imag__ x))
79 {
80 __real__ res = __real__ y;
81 __imag__ res = -__imag__ y;
82 }
83 else
84 {
85 __real__ res = -__real__ y;
86 __imag__ res = __imag__ y;
87 }
88 }
89
90 return res;
91}
92
93declare_mgen_alias (__cacosh, cacosh)
94

source code of glibc/math/s_cacosh_template.c