xref: /illumos-gate/usr/src/head/values.h (revision b4203d757c7c247e39c94c09a94021a3a8121062)
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 /*	Copyright (c) 1988 AT&T	*/
23 /*	  All Rights Reserved	*/
24 
25 
26 /*
27  * Copyright 2014 Garrett D'Amore <garrett@damore.org>
28  *
29  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
30  * Use is subject to license terms.
31  */
32 
33 #ifndef	_VALUES_H
34 #define	_VALUES_H
35 
36 #include <sys/isa_defs.h>
37 
38 #ifdef	__cplusplus
39 extern "C" {
40 #endif
41 
42 /*
43  * These values work with any binary representation of integers
44  * where the high-order bit contains the sign.
45  */
46 
47 /* a number used normally for size of a shift */
48 #define	BITSPERBYTE	8
49 
50 #define	BITS(type)	(BITSPERBYTE * (long)sizeof (type))
51 
52 /* short, regular and long ints with only the high-order bit turned on */
53 #define	HIBITS	((short)(1 << (BITS(short) - 1)))
54 
55 #define	HIBITI	(1U << (BITS(int) - 1))
56 #define	HIBITL	(1UL << (BITS(long) - 1))
57 
58 /* largest short, regular and long int */
59 #define	MAXSHORT	((short)~HIBITS)
60 #define	MAXINT		((int)(~HIBITI))
61 #define	MAXLONG		((long)(~HIBITL))
62 
63 /*
64  * various values that describe the binary floating-point representation
65  * _EXPBASE	- the exponent base
66  * DMAXEXP	- the maximum exponent of a double (as returned by frexp())
67  * FMAXEXP	- the maximum exponent of a float  (as returned by frexp())
68  * DMINEXP	- the minimum exponent of a double (as returned by frexp())
69  * FMINEXP	- the minimum exponent of a float  (as returned by frexp())
70  * MAXDOUBLE	- the largest double
71  *			((_EXPBASE ** DMAXEXP) * (1 - (_EXPBASE ** -DSIGNIF)))
72  * MAXFLOAT	- the largest float
73  *			((_EXPBASE ** FMAXEXP) * (1 - (_EXPBASE ** -FSIGNIF)))
74  * MINDOUBLE	- the smallest double (_EXPBASE ** (DMINEXP - 1))
75  * MINFLOAT	- the smallest float (_EXPBASE ** (FMINEXP - 1))
76  * DSIGNIF	- the number of significant bits in a double
77  * FSIGNIF	- the number of significant bits in a float
78  * DMAXPOWTWO	- the largest power of two exactly representable as a double
79  * FMAXPOWTWO	- the largest power of two exactly representable as a float
80  * _IEEE	- 1 if IEEE standard representation is used
81  * _DEXPLEN	- the number of bits for the exponent of a double
82  * _FEXPLEN	- the number of bits for the exponent of a float
83  * _HIDDENBIT	- 1 if high-significance bit of mantissa is implicit
84  * LN_MAXDOUBLE	- the natural log of the largest double  -- log(MAXDOUBLE)
85  * LN_MINDOUBLE	- the natural log of the smallest double -- log(MINDOUBLE)
86  * LN_MAXFLOAT	- the natural log of the largest float  -- log(MAXFLOAT)
87  * LN_MINFLOAT	- the natural log of the smallest float -- log(MINFLOAT)
88  */
89 
90 /*
91  * Currently, only IEEE-754 format is supported.
92  */
93 #if defined(_IEEE_754)
94 #define	MAXDOUBLE	1.79769313486231570e+308
95 #define	MAXFLOAT	((float)3.40282346638528860e+38)
96 #define	MINDOUBLE	4.94065645841246544e-324
97 #define	MINFLOAT	((float)1.40129846432481707e-45)
98 #define	_IEEE		1
99 #define	_DEXPLEN	11
100 #define	_HIDDENBIT	1
101 #define	_LENBASE	1
102 #define	DMINEXP	(-(DMAXEXP + DSIGNIF - _HIDDENBIT - 3))
103 #define	FMINEXP	(-(FMAXEXP + FSIGNIF - _HIDDENBIT - 3))
104 #else
105 /* #error is strictly ansi-C, but works as well as anything for K&R systems. */
106 #error "ISA not supported"
107 #endif
108 
109 #define	_EXPBASE	(1 << _LENBASE)
110 #define	_FEXPLEN	8
111 #define	DSIGNIF	(BITS(double) - _DEXPLEN + _HIDDENBIT - 1)
112 #define	FSIGNIF	(BITS(float)  - _FEXPLEN + _HIDDENBIT - 1)
113 #define	DMAXPOWTWO	((double)(1 << (BITS(int) - 2)) * \
114 				(1 << (DSIGNIF - BITS(int) + 1)))
115 #define	FMAXPOWTWO	((float)(1 << (FSIGNIF - 1)))
116 #define	DMAXEXP	((1 << (_DEXPLEN - 1)) - 1 + _IEEE)
117 #define	FMAXEXP	((1 << (_FEXPLEN - 1)) - 1 + _IEEE)
118 #define	LN_MAXDOUBLE	(M_LN2 * DMAXEXP)
119 #define	LN_MAXFLOAT	(float)(M_LN2 * FMAXEXP)
120 #define	LN_MINDOUBLE	(M_LN2 * (DMINEXP - 1))
121 #define	LN_MINFLOAT	(float)(M_LN2 * (FMINEXP - 1))
122 #define	H_PREC	(DSIGNIF % 2 ? (1 << DSIGNIF/2) * M_SQRT2 : 1 << DSIGNIF/2)
123 #define	FH_PREC \
124 	(float)(FSIGNIF % 2 ? (1 << FSIGNIF/2) * M_SQRT2 : 1 << FSIGNIF/2)
125 #define	X_EPS	(1.0/H_PREC)
126 #define	FX_EPS	(float)((float)1.0/FH_PREC)
127 #define	X_PLOSS	((double)(int)(M_PI * H_PREC))
128 #define	FX_PLOSS ((float)(int)(M_PI * FH_PREC))
129 #define	X_TLOSS	(M_PI * DMAXPOWTWO)
130 #define	FX_TLOSS (float)(M_PI * FMAXPOWTWO)
131 #define	M_LN2	0.69314718055994530942
132 #define	M_PI	3.14159265358979323846
133 #define	M_SQRT2	1.41421356237309504880
134 #define	MAXBEXP	DMAXEXP /* for backward compatibility */
135 #define	MINBEXP	DMINEXP /* for backward compatibility */
136 #define	MAXPOWTWO	DMAXPOWTWO /* for backward compatibility */
137 
138 #ifdef	__cplusplus
139 }
140 #endif
141 
142 #endif	/* _VALUES_H */
143