xref: /netbsd-src/sys/arch/m68k/include/ieee.h (revision aaf4ece63a859a04e37cf3a7229b5fab0157cc06)
1 /*	$NetBSD: ieee.h,v 1.12 2005/12/11 12:17:53 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This software was developed by the Computer Systems Engineering group
8  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
9  * contributed to Berkeley.
10  *
11  * All advertising materials mentioning features or use of this software
12  * must display the following acknowledgement:
13  *	This product includes software developed by the University of
14  *	California, Lawrence Berkeley Laboratory.
15  *
16  * Redistribution and use in source and binary forms, with or without
17  * modification, are permitted provided that the following conditions
18  * are met:
19  * 1. Redistributions of source code must retain the above copyright
20  *    notice, this list of conditions and the following disclaimer.
21  * 2. Redistributions in binary form must reproduce the above copyright
22  *    notice, this list of conditions and the following disclaimer in the
23  *    documentation and/or other materials provided with the distribution.
24  * 3. Neither the name of the University nor the names of its contributors
25  *    may be used to endorse or promote products derived from this software
26  *    without specific prior written permission.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38  * SUCH DAMAGE.
39  *
40  *	@(#)ieee.h	8.1 (Berkeley) 6/11/93
41  */
42 
43 /*
44  * ieee.h defines the machine-dependent layout of the machine's IEEE
45  * floating point.  It does *not* define (yet?) any of the rounding
46  * mode bits, exceptions, and so forth.
47  */
48 
49 #include <sys/ieee754.h>
50 
51 #if !defined(__mc68010__) || defined(_KERNEL)
52 #define	EXT_EXPBITS	15
53 #define	EXT_FRACBITS	64
54 
55 struct ieee_ext {
56 	u_int	ext_sign:1;
57 	u_int	ext_exp:15;
58 	u_int	ext_zero:16;
59 	u_int	ext_int:1;
60 	u_int	ext_frach:31;
61 	u_int	ext_fracl;
62 };
63 
64 /*
65  * Extended floats whose exponent is in [0..INFNAN) and have their
66  * explicit integer bit (the most significant bit of the fraction)
67  * set are `normal'.  Floats whose exponent is INFNAN are either Inf or NaN.
68  * Floats whose exponent is zero are either zero (iff all fraction
69  * bits are zero) or subnormal values.
70  *
71  * A NaN is a `signalling NaN' if its QUIETNAN bit is clear in its
72  * high fraction; if the bit is set, it is a `quiet NaN'.
73  */
74 #define	EXT_EXP_INFNAN	32767
75 
76 #if 0
77 #define	SNG_QUIETNAN	(1 << 22)
78 #define	DBL_QUIETNAN	(1 << 19)
79 #define	EXT_QUIETNAN	(1 << 30)
80 #endif
81 
82 /*
83  * Exponent biases.
84  */
85 #define	EXT_EXP_BIAS	16383
86 
87 /*
88  * Convenience data structures.
89  */
90 union ieee_ext_u {
91 	long double		extu_ld;
92 	struct ieee_ext		extu_ext;
93 };
94 
95 #endif /* !__mc68010__ || _KERNEL */
96