]>
Commit | Line | Data |
---|---|---|
feb62dda | 1 | /* Return value of complex exponential function for a float type. |
2b778ceb | 2 | Copyright (C) 1997-2021 Free Software Foundation, Inc. |
1dbc54f6 | 3 | This file is part of the GNU C Library. |
1dbc54f6 PM |
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 | |
5a82c748 | 17 | <https://www.gnu.org/licenses/>. */ |
1dbc54f6 PM |
18 | |
19 | #include <complex.h> | |
20 | #include <fenv.h> | |
21 | #include <math.h> | |
22 | #include <math_private.h> | |
8f5b00d3 | 23 | #include <math-underflow.h> |
1dbc54f6 PM |
24 | #include <float.h> |
25 | ||
feb62dda PM |
26 | CFLOAT |
27 | M_DECL_FUNC (__cexp) (CFLOAT x) | |
1dbc54f6 | 28 | { |
feb62dda | 29 | CFLOAT retval; |
1dbc54f6 PM |
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. */ | |
feb62dda PM |
39 | const int t = (int) ((M_MAX_EXP - 1) * M_MLIT (M_LN2)); |
40 | FLOAT sinix, cosix; | |
1dbc54f6 | 41 | |
feb62dda | 42 | if (__glibc_likely (M_FABS (__imag__ x) > M_MIN)) |
1dbc54f6 | 43 | { |
feb62dda | 44 | M_SINCOS (__imag__ x, &sinix, &cosix); |
1dbc54f6 PM |
45 | } |
46 | else | |
47 | { | |
48 | sinix = __imag__ x; | |
feb62dda | 49 | cosix = 1; |
1dbc54f6 PM |
50 | } |
51 | ||
52 | if (__real__ x > t) | |
53 | { | |
feb62dda | 54 | FLOAT exp_t = M_EXP (t); |
1dbc54f6 PM |
55 | __real__ x -= t; |
56 | sinix *= exp_t; | |
57 | cosix *= exp_t; | |
58 | if (__real__ x > t) | |
59 | { | |
60 | __real__ x -= t; | |
61 | sinix *= exp_t; | |
62 | cosix *= exp_t; | |
63 | } | |
64 | } | |
65 | if (__real__ x > t) | |
66 | { | |
67 | /* Overflow (original real part of x > 3t). */ | |
feb62dda PM |
68 | __real__ retval = M_MAX * cosix; |
69 | __imag__ retval = M_MAX * sinix; | |
1dbc54f6 PM |
70 | } |
71 | else | |
72 | { | |
feb62dda | 73 | FLOAT exp_val = M_EXP (__real__ x); |
1dbc54f6 PM |
74 | __real__ retval = exp_val * cosix; |
75 | __imag__ retval = exp_val * sinix; | |
76 | } | |
77 | math_check_force_underflow_complex (retval); | |
78 | } | |
79 | else | |
80 | { | |
81 | /* If the imaginary part is +-inf or NaN and the real part | |
82 | is not +-inf the result is NaN + iNaN. */ | |
feb62dda PM |
83 | __real__ retval = M_NAN; |
84 | __imag__ retval = M_NAN; | |
1dbc54f6 PM |
85 | |
86 | feraiseexcept (FE_INVALID); | |
87 | } | |
88 | } | |
89 | else if (__glibc_likely (rcls == FP_INFINITE)) | |
90 | { | |
91 | /* Real part is infinite. */ | |
92 | if (__glibc_likely (icls >= FP_ZERO)) | |
93 | { | |
94 | /* Imaginary part is finite. */ | |
feb62dda | 95 | FLOAT value = signbit (__real__ x) ? 0 : M_HUGE_VAL; |
1dbc54f6 PM |
96 | |
97 | if (icls == FP_ZERO) | |
98 | { | |
99 | /* Imaginary part is 0.0. */ | |
100 | __real__ retval = value; | |
101 | __imag__ retval = __imag__ x; | |
102 | } | |
103 | else | |
104 | { | |
feb62dda | 105 | FLOAT sinix, cosix; |
1dbc54f6 | 106 | |
feb62dda | 107 | if (__glibc_likely (M_FABS (__imag__ x) > M_MIN)) |
1dbc54f6 | 108 | { |
feb62dda | 109 | M_SINCOS (__imag__ x, &sinix, &cosix); |
1dbc54f6 PM |
110 | } |
111 | else | |
112 | { | |
113 | sinix = __imag__ x; | |
feb62dda | 114 | cosix = 1; |
1dbc54f6 PM |
115 | } |
116 | ||
feb62dda PM |
117 | __real__ retval = M_COPYSIGN (value, cosix); |
118 | __imag__ retval = M_COPYSIGN (value, sinix); | |
1dbc54f6 PM |
119 | } |
120 | } | |
121 | else if (signbit (__real__ x) == 0) | |
122 | { | |
feb62dda | 123 | __real__ retval = M_HUGE_VAL; |
e886c367 | 124 | __imag__ retval = __imag__ x - __imag__ x; |
1dbc54f6 PM |
125 | } |
126 | else | |
127 | { | |
feb62dda PM |
128 | __real__ retval = 0; |
129 | __imag__ retval = M_COPYSIGN (0, __imag__ x); | |
1dbc54f6 PM |
130 | } |
131 | } | |
132 | else | |
133 | { | |
134 | /* If the real part is NaN the result is NaN + iNaN unless the | |
135 | imaginary part is zero. */ | |
feb62dda | 136 | __real__ retval = M_NAN; |
1dbc54f6 PM |
137 | if (icls == FP_ZERO) |
138 | __imag__ retval = __imag__ x; | |
139 | else | |
140 | { | |
feb62dda | 141 | __imag__ retval = M_NAN; |
1dbc54f6 PM |
142 | |
143 | if (rcls != FP_NAN || icls != FP_NAN) | |
144 | feraiseexcept (FE_INVALID); | |
145 | } | |
146 | } | |
147 | ||
148 | return retval; | |
149 | } | |
feb62dda | 150 | declare_mgen_alias (__cexp, cexp) |