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 
26 CFLOAT
M_DECL_FUNC(__csinh)27 M_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 
156 declare_mgen_alias (__csinh, csinh)
157