1/* Complex sine hyperbole function for float types.
2 Copyright (C) 1997-2022 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 <fenv.h>
21#include <math.h>
22#include <math_private.h>
23#include <math-underflow.h>
24#include <float.h>
25
26CFLOAT
27M_DECL_FUNC (__csinh) (CFLOAT x)
28{
29 CFLOAT retval;
30 int negate = signbit (__real__ x);
31 int rcls = fpclassify (__real__ x);
32 int icls = fpclassify (__imag__ x);
33
34 __real__ x = M_FABS (__real__ x);
35
36 if (__glibc_likely (rcls >= FP_ZERO))
37 {
38 /* Real part is finite. */
39 if (__glibc_likely (icls >= FP_ZERO))
40 {
41 /* Imaginary part is finite. */
42 const int t = (int) ((M_MAX_EXP - 1) * M_MLIT (M_LN2));
43 FLOAT sinix, cosix;
44
45 if (__glibc_likely (M_FABS (__imag__ x) > M_MIN))
46 {
47 M_SINCOS (__imag__ x, &sinix, &cosix);
48 }
49 else
50 {
51 sinix = __imag__ x;
52 cosix = 1;
53 }
54
55 if (negate)
56 cosix = -cosix;
57
58 if (M_FABS (__real__ x) > t)
59 {
60 FLOAT exp_t = M_EXP (t);
61 FLOAT rx = M_FABS (__real__ x);
62 if (signbit (__real__ x))
63 cosix = -cosix;
64 rx -= t;
65 sinix *= exp_t / 2;
66 cosix *= exp_t / 2;
67 if (rx > t)
68 {
69 rx -= t;
70 sinix *= exp_t;
71 cosix *= exp_t;
72 }
73 if (rx > t)
74 {
75 /* Overflow (original real part of x > 3t). */
76 __real__ retval = M_MAX * cosix;
77 __imag__ retval = M_MAX * sinix;
78 }
79 else
80 {
81 FLOAT exp_val = M_EXP (rx);
82 __real__ retval = exp_val * cosix;
83 __imag__ retval = exp_val * sinix;
84 }
85 }
86 else
87 {
88 __real__ retval = M_SINH (__real__ x) * cosix;
89 __imag__ retval = M_COSH (__real__ x) * sinix;
90 }
91
92 math_check_force_underflow_complex (retval);
93 }
94 else
95 {
96 if (rcls == FP_ZERO)
97 {
98 /* Real part is 0.0. */
99 __real__ retval = M_COPYSIGN (0, negate ? -1 : 1);
100 __imag__ retval = __imag__ x - __imag__ x;
101 }
102 else
103 {
104 __real__ retval = M_NAN;
105 __imag__ retval = M_NAN;
106
107 feraiseexcept (FE_INVALID);
108 }
109 }
110 }
111 else if (rcls == FP_INFINITE)
112 {
113 /* Real part is infinite. */
114 if (__glibc_likely (icls > FP_ZERO))
115 {
116 /* Imaginary part is finite. */
117 FLOAT sinix, cosix;
118
119 if (__glibc_likely (M_FABS (__imag__ x) > M_MIN))
120 {
121 M_SINCOS (__imag__ x, &sinix, &cosix);
122 }
123 else
124 {
125 sinix = __imag__ x;
126 cosix = 1;
127 }
128
129 __real__ retval = M_COPYSIGN (M_HUGE_VAL, cosix);
130 __imag__ retval = M_COPYSIGN (M_HUGE_VAL, sinix);
131
132 if (negate)
133 __real__ retval = -__real__ retval;
134 }
135 else if (icls == FP_ZERO)
136 {
137 /* Imaginary part is 0.0. */
138 __real__ retval = negate ? -M_HUGE_VAL : M_HUGE_VAL;
139 __imag__ retval = __imag__ x;
140 }
141 else
142 {
143 __real__ retval = M_HUGE_VAL;
144 __imag__ retval = __imag__ x - __imag__ x;
145 }
146 }
147 else
148 {
149 __real__ retval = M_NAN;
150 __imag__ retval = __imag__ x == 0 ? __imag__ x : M_NAN;
151 }
152
153 return retval;
154}
155
156declare_mgen_alias (__csinh, csinh)
157

source code of glibc/math/s_csinh_template.c