1/*	$OpenBSD: fenv.h,v 1.2 2011/05/25 21:46:49 martynas Exp $	*/
2
3/*
4 * Copyright (c) 2011 Martynas Venckus <martynas@openbsd.org>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19#ifndef	_M88K_FENV_H_
20#define	_M88K_FENV_H_
21
22/*
23 * Each symbol representing a floating point exception expands to an integer
24 * constant expression with values, such that bitwise-inclusive ORs of _all
25 * combinations_ of the constants result in distinct values.
26 *
27 * We use such values that allow direct bitwise operations on FPU registers.
28 */
29#define	FE_INEXACT		0x01
30#define	FE_OVERFLOW		0x02
31#define	FE_UNDERFLOW		0x04
32#define	FE_DIVBYZERO		0x08
33#define	FE_INVALID		0x10
34
35/*
36 * The following symbol is simply the bitwise-inclusive OR of all floating-point
37 * exception constants defined above.
38 */
39#define	FE_ALL_EXCEPT		(FE_INEXACT | FE_DIVBYZERO | FE_UNDERFLOW | \
40				 FE_OVERFLOW | FE_INVALID)
41
42/*
43 * Each symbol representing the rounding direction, expands to an integer
44 * constant expression whose value is distinct non-negative value.
45 *
46 * We use such values that allow direct bitwise operations on FPU registers.
47 */
48#define	FE_TONEAREST		0x0000
49#define	FE_TOWARDZERO		0x4000
50#define	FE_DOWNWARD		0x8000
51#define	FE_UPWARD		0xC000
52
53/*
54 * The following symbol is simply the bitwise-inclusive OR of all floating-point
55 * rounding direction constants defined above.
56 */
57#define	_ROUND_MASK		(FE_TONEAREST | FE_TOWARDZERO | FE_DOWNWARD | \
58				 FE_UPWARD)
59
60/*
61 * fenv_t represents the entire floating-point environment.
62 */
63typedef	struct {
64	unsigned int __control;			/* Control register */
65	unsigned int __status;			/* Status register */
66} fenv_t;
67
68/*
69 * The following constant represents the default floating-point environment
70 * (that is, the one installed at program startup) and has type pointer to
71 * const-qualified fenv_t.
72 *
73 * It can be used as an argument to the functions within the <fenv.h> header
74 * that manage the floating-point environment, namely fesetenv() and
75 * feupdateenv().
76 */
77__BEGIN_DECLS
78extern	fenv_t			__fe_dfl_env;
79__END_DECLS
80#define	FE_DFL_ENV		((const fenv_t *)&__fe_dfl_env)
81
82/*
83 * fexcept_t represents the floating-point status flags collectively, including
84 * any status the implementation associates with the flags.
85 *
86 * A floating-point status flag is a system variable whose value is set (but
87 * never cleared) when a floating-point exception is raised, which occurs as a
88 * side effect of exceptional floating-point arithmetic to provide auxiliary
89 * information.
90 *
91 * A floating-point control mode is a system variable whose value may be set by
92 * the user to affect the subsequent behavior of floating-point arithmetic.
93 */
94typedef	unsigned int		fexcept_t;
95
96#endif	/* !_M88K_FENV_H_ */
97