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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include "synonyms.h"
30 #include <sys/ieeefp.h>
31 #include <ieeefp.h>
32 
33 static const double zero = 0.0, tiny = 1.0e-307, tiny2 = 1.001e-307,
34 	huge = 1.0e300;
35 
36 /*
37  * _Q_set_exception(ex) simulates the floating point exceptions indicated by
38  * ex.  This routine is not used by the new quad emulation routines but is
39  * still used by ../crt/_ftoll.c.
40  */
41 int
42 _Q_set_exception(unsigned int ex)
43 {
44 	/* LINTED set but not used */
45 	volatile double t;
46 
47 	if (ex == 0)
48 		t = zero - zero;			/* clear cexc */
49 	else {
50 		if ((ex & (1 << fp_invalid)) != 0)
51 			t = zero / zero;
52 		if ((ex & (1 << fp_overflow)) != 0)
53 			t = huge * huge;
54 		if ((ex & (1 << fp_underflow)) != 0) {
55 			if ((ex & (1 << fp_inexact)) != 0 ||
56 			    (fpgetmask() & FP_X_UFL) != 0)
57 				t = tiny * tiny;
58 			else
59 				t = tiny2 - tiny;	/* exact */
60 		}
61 		if ((ex & (1 << fp_division)) != 0)
62 			t = tiny / zero;
63 		if ((ex & (1 << fp_inexact)) != 0)
64 			t = huge + tiny;
65 	}
66 	return (0);
67 }
68