xref: /illumos-gate/usr/src/lib/libm/common/m9x/feexcept.c (revision b515258426fed6c7311fd3f1dea697cfbd4085c6)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
24  */
25 /*
26  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
27  * Use is subject to license terms.
28  */
29 
30 #pragma weak feclearexcept = __feclearexcept
31 #pragma weak feraiseexcept = __feraiseexcept
32 #pragma weak fetestexcept = __fetestexcept
33 #pragma weak fegetexceptflag = __fegetexceptflag
34 #pragma weak fesetexceptflag = __fesetexceptflag
35 
36 #pragma weak feclearexcept96 = __feclearexcept
37 #pragma weak feraiseexcept96 = __feraiseexcept
38 #pragma weak fetestexcept96 = __fetestexcept
39 #pragma weak fegetexceptflag96 = __fegetexceptflag
40 #pragma weak fesetexceptflag96 = __fesetexceptflag
41 
42 #include "fenv_synonyms.h"
43 #include <fenv.h>
44 #include <sys/ieeefp.h>
45 #include <ucontext.h>
46 #include <thread.h>
47 #include "fex_handler.h"
48 #include "fenv_inlines.h"
49 
50 
51 int feclearexcept(int e)
52 {
53 	unsigned long	fsr;
54 
55 	__fenv_getfsr(&fsr);
56 	__fenv_set_ex(fsr, __fenv_get_ex(fsr) & ~e);
57 	__fenv_setfsr(&fsr);
58 	if (fex_get_log())
59 		__fex_update_te();
60 	return 0;
61 }
62 
63 /*
64 *  note - __fex_hdlr depends on fetestexcept following feraiseexcept
65 */
66 int feraiseexcept(int e)
67 {
68 	volatile double	t;
69 	unsigned long	fsr;
70 
71 	if (e & FE_INVALID) {
72 		t = 0.0;
73 		t /= 0.0;
74 	}
75 	if (e & FE_DIVBYZERO) {
76 		t = 1.0e300;
77 		t /= 0.0;
78 	}
79 	if (e & FE_OVERFLOW) {
80 		/* if overflow is not trapped, avoid raising inexact */
81 		__fenv_getfsr(&fsr);
82 		if (!(__fenv_get_te(fsr) & (1 << fp_trap_overflow))) {
83 			__fenv_set_ex(fsr, __fenv_get_ex(fsr) | FE_OVERFLOW);
84 			__fenv_setfsr(&fsr);
85 		}
86 		else {
87 			t = 1.0e300;
88 			t *= 1.0e300;
89 		}
90 	}
91 	if (e & FE_UNDERFLOW) {
92 		/* if underflow is not trapped, avoid raising inexact */
93 		__fenv_getfsr(&fsr);
94 		if (!(__fenv_get_te(fsr) & (1 << fp_trap_underflow))) {
95 			__fenv_set_ex(fsr, __fenv_get_ex(fsr) | FE_UNDERFLOW);
96 			__fenv_setfsr(&fsr);
97 		}
98 		else {
99 			t = 1.0e-307;
100 			t -= 1.001e-307;
101 		}
102 	}
103 	if (e & FE_INEXACT) {
104 		t = 1.0e300;
105 		t += 1.0e-307;
106 	}
107 	return 0;
108 }
109 
110 int fetestexcept(int e)
111 {
112 	unsigned long	fsr;
113 
114 	__fenv_getfsr(&fsr);
115 	return (int)__fenv_get_ex(fsr) & e;
116 }
117 
118 int fegetexceptflag(fexcept_t *p, int e)
119 {
120 	unsigned long	fsr;
121 
122 	__fenv_getfsr(&fsr);
123 	*p = (int)__fenv_get_ex(fsr) & e;
124 	return 0;
125 }
126 
127 int fesetexceptflag(const fexcept_t *p, int e)
128 {
129 	unsigned long	fsr;
130 
131 	__fenv_getfsr(&fsr);
132 	__fenv_set_ex(fsr, (((int)__fenv_get_ex(fsr) & ~e) | (*p & e)) &
133 		FE_ALL_EXCEPT);
134 	__fenv_setfsr(&fsr);
135 	if (fex_get_log())
136 		__fex_update_te();
137 	return 0;
138 }
139