1 /* Complex exponential function. m68k fpu version
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 <float.h>
20 #include <complex.h>
21 #include <math.h>
22 #include "mathimpl.h"
23
24 #define CONCATX(a,b) __CONCAT(a,b)
25 #define s(name) M_SUF (name)
26 #define m81(func) __m81_u(s(func))
27
28 CFLOAT
s(__cexp)29 s(__cexp) (CFLOAT x)
30 {
31 CFLOAT retval;
32 unsigned long ix_cond;
33
34 ix_cond = __m81_test (__imag__ x);
35
36 if ((ix_cond & (__M81_COND_NAN|__M81_COND_INF)) == 0)
37 {
38 /* Imaginary part is finite. */
39 unsigned long rx_cond = __m81_test (__real__ x);
40
41 if ((rx_cond & (__M81_COND_NAN|__M81_COND_INF)) == 0)
42 {
43 const int t = (int) ((LDBL_MAX_EXP - 1) * M_LN2l);
44 long double sin_ix, cos_ix, exp_val;
45
46 __m81_u (__sincosl) (__imag__ x, &sin_ix, &cos_ix);
47
48 if (__real__ x > t)
49 {
50 long double exp_t = __m81_u(__ieee754_expl) (t);
51 __real__ x -= t;
52 sin_ix *= exp_t;
53 cos_ix *= exp_t;
54 if (__real__ x > t)
55 {
56 __real__ x -= t;
57 sin_ix *= exp_t;
58 cos_ix *= exp_t;
59 }
60 }
61
62 exp_val = __m81_u(__ieee754_expl) (__real__ x);
63 __real__ retval = exp_val * cos_ix;
64 if (ix_cond & __M81_COND_ZERO)
65 __imag__ retval = __imag__ x;
66 else
67 __imag__ retval = exp_val * sin_ix;
68 }
69 else
70 {
71 /* Compute the sign of the result. */
72 long double remainder, pi_2;
73 int quadrant;
74
75 if ((rx_cond & (__M81_COND_NAN|__M81_COND_NEG)) == __M81_COND_NEG)
76 __real__ retval = __imag__ retval = 0.0;
77 else
78 __real__ retval = __imag__ retval = __real__ x;
79 __asm ("fmovecr %#0,%0\n\tfscale%.w %#-1,%0" : "=f" (pi_2));
80 __asm ("fmod%.x %2,%0\n\tfmove%.l %/fpsr,%1"
81 : "=f" (remainder), "=dm" (quadrant)
82 : "f" (pi_2), "0" (__imag__ x));
83 quadrant = (quadrant >> 16) & 0x83;
84 if (quadrant & 0x80)
85 quadrant ^= 0x83;
86 switch (quadrant)
87 {
88 default:
89 break;
90 case 1:
91 __real__ retval = -__real__ retval;
92 break;
93 case 2:
94 __real__ retval = -__real__ retval;
95 /* Fall through. */
96 case 3:
97 __imag__ retval = -__imag__ retval;
98 break;
99 }
100 if (ix_cond & __M81_COND_ZERO && (rx_cond & __M81_COND_NAN) == 0)
101 __imag__ retval = __imag__ x;
102 }
103 }
104 else
105 {
106 unsigned long rx_cond = __m81_test (__real__ x);
107
108 if (rx_cond & __M81_COND_INF)
109 {
110 /* Real part is infinite. */
111 if (rx_cond & __M81_COND_NEG)
112 {
113 __real__ retval = __imag__ retval = 0.0;
114 if (ix_cond & __M81_COND_NEG)
115 __imag__ retval = -__imag__ retval;
116 }
117 else
118 {
119 __real__ retval = __real__ x;
120 __imag__ retval = __imag__ x - __imag__ x;
121 }
122 }
123 else
124 __real__ retval = __imag__ retval = __imag__ x - __imag__ x;
125 }
126
127 return retval;
128 }
129 declare_mgen_alias (__cexp, cexp)
130