1 /* Implement __kernel_standard_l.
2 Copyright (C) 2012-2016 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 <http://www.gnu.org/licenses/>.
18
19 Parts based on k_standard.c from fdlibm: */
20
21 /* @(#)k_standard.c 5.1 93/09/24 */
22 /*
23 * ====================================================
24 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
25 *
26 * Developed at SunPro, a Sun Microsystems, Inc. business.
27 * Permission to use, copy, modify, and distribute this
28 * software is freely granted, provided that this notice
29 * is preserved.
30 * ====================================================
31 */
32
33 #include <math.h>
34 #include "math_private.h"
35 #include <fenv.h>
36 #include <float.h>
37 #include <errno.h>
38
39
40 static double zero = 0.0;
41
42 /* Handle errors for a libm function as specified by TYPE (see
43 comments in k_standard.c for details), with arguments X and Y,
44 returning the appropriate return value for that function. */
45
46 long double
__kernel_standard_l(long double x,long double y,int type)47 __kernel_standard_l (long double x, long double y, int type)
48 {
49 double dx, dy;
50 struct exception exc;
51 fenv_t env;
52
53 feholdexcept (&env);
54 dx = x;
55 dy = y;
56 math_force_eval (dx);
57 math_force_eval (dy);
58 fesetenv (&env);
59
60 switch (type)
61 {
62 case 221:
63 /* powl (x, y) overflow. */
64 exc.arg1 = dx;
65 exc.arg2 = dy;
66 exc.type = OVERFLOW;
67 exc.name = (char *) "powl";
68 if (_LIB_VERSION == _SVID_)
69 {
70 exc.retval = HUGE;
71 y *= 0.5;
72 if (x < zero && rint (y) != y)
73 exc.retval = -HUGE;
74 }
75 else
76 {
77 exc.retval = HUGE_VAL;
78 y *= 0.5;
79 if (x < zero && rint (y) != y)
80 exc.retval = -HUGE_VAL;
81 }
82 if (_LIB_VERSION == _POSIX_)
83 __set_errno (ERANGE);
84 else if (!matherr (&exc))
85 __set_errno (ERANGE);
86 return exc.retval;
87
88 case 222:
89 /* powl (x, y) underflow. */
90 exc.arg1 = dx;
91 exc.arg2 = dy;
92 exc.type = UNDERFLOW;
93 exc.name = (char *) "powl";
94 exc.retval = zero;
95 y *= 0.5;
96 if (x < zero && rint (y) != y)
97 exc.retval = -zero;
98 if (_LIB_VERSION == _POSIX_)
99 __set_errno (ERANGE);
100 else if (!matherr (&exc))
101 __set_errno (ERANGE);
102 return exc.retval;
103
104 default:
105 return __kernel_standard (dx, dy, type);
106 }
107 }
108