fenv.h revision 331722 
1/*-
2 * Copyright (c) 2004-2005 David Schultz <das@FreeBSD.ORG>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: stable/11/lib/msun/mips/fenv.h 331722 2018-03-29 02:50:57Z eadler $
27 */
28
29#ifndef	_FENV_H_
30#define	_FENV_H_
31
32#include <sys/_types.h>
33
34#ifndef	__fenv_static
35#define	__fenv_static	static
36#endif
37
38typedef	__uint32_t	fenv_t;
39typedef	__uint32_t	fexcept_t;
40
41/* Exception flags */
42#define	FE_INVALID	0x0001
43#define	FE_DIVBYZERO	0x0002
44#define	FE_OVERFLOW	0x0004
45#define	FE_UNDERFLOW	0x0008
46#define	FE_INEXACT	0x0010
47#define	FE_ALL_EXCEPT	(FE_DIVBYZERO | FE_INEXACT | \
48			 FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW)
49
50/* Rounding modes */
51#define	FE_TONEAREST	0x0000
52#define	FE_TOWARDZERO	0x0001
53#define	FE_UPWARD	0x0002
54#define	FE_DOWNWARD	0x0003
55#define	_ROUND_MASK	(FE_TONEAREST | FE_DOWNWARD | \
56			 FE_UPWARD | FE_TOWARDZERO)
57__BEGIN_DECLS
58
59/* Default floating-point environment */
60extern const fenv_t	__fe_dfl_env;
61#define	FE_DFL_ENV	(&__fe_dfl_env)
62
63/* We need to be able to map status flag positions to mask flag positions */
64#define _FPUSW_SHIFT	16
65#define	_ENABLE_MASK	(FE_ALL_EXCEPT << _FPUSW_SHIFT)
66
67#ifdef	ARM_HARD_FLOAT
68#define	__rfs(__fpsr)	__asm __volatile("rfs %0" : "=r" (*(__fpsr)))
69#define	__wfs(__fpsr)	__asm __volatile("wfs %0" : : "r" (__fpsr))
70#else
71#define __rfs(__fpsr)
72#define __wfs(__fpsr)
73#endif
74
75__fenv_static inline int
76feclearexcept(int __excepts)
77{
78	fexcept_t __fpsr;
79
80	__rfs(&__fpsr);
81	__fpsr &= ~__excepts;
82	__wfs(__fpsr);
83	return (0);
84}
85
86__fenv_static inline int
87fegetexceptflag(fexcept_t *__flagp, int __excepts)
88{
89	fexcept_t __fpsr;
90
91	__rfs(&__fpsr);
92	*__flagp = __fpsr & __excepts;
93	return (0);
94}
95
96__fenv_static inline int
97fesetexceptflag(const fexcept_t *__flagp, int __excepts)
98{
99	fexcept_t __fpsr;
100
101	__rfs(&__fpsr);
102	__fpsr &= ~__excepts;
103	__fpsr |= *__flagp & __excepts;
104	__wfs(__fpsr);
105	return (0);
106}
107
108__fenv_static inline int
109feraiseexcept(int __excepts)
110{
111	fexcept_t __ex = __excepts;
112
113	fesetexceptflag(&__ex, __excepts);	/* XXX */
114	return (0);
115}
116
117__fenv_static inline int
118fetestexcept(int __excepts)
119{
120	fexcept_t __fpsr;
121
122	__rfs(&__fpsr);
123	return (__fpsr & __excepts);
124}
125
126__fenv_static inline int
127fegetround(void)
128{
129
130	/*
131	 * Apparently, the rounding mode is specified as part of the
132	 * instruction format on ARM, so the dynamic rounding mode is
133	 * indeterminate.  Some FPUs may differ.
134	 */
135	return (-1);
136}
137
138__fenv_static inline int
139fesetround(int __round)
140{
141
142	return (-1);
143}
144
145__fenv_static inline int
146fegetenv(fenv_t *__envp)
147{
148
149	__rfs(__envp);
150	return (0);
151}
152
153__fenv_static inline int
154feholdexcept(fenv_t *__envp)
155{
156	fenv_t __env;
157
158	__rfs(&__env);
159	*__envp = __env;
160	__env &= ~(FE_ALL_EXCEPT | _ENABLE_MASK);
161	__wfs(__env);
162	return (0);
163}
164
165__fenv_static inline int
166fesetenv(const fenv_t *__envp)
167{
168
169	__wfs(*__envp);
170	return (0);
171}
172
173__fenv_static inline int
174feupdateenv(const fenv_t *__envp)
175{
176	fexcept_t __fpsr;
177
178	__rfs(&__fpsr);
179	__wfs(*__envp);
180	feraiseexcept(__fpsr & FE_ALL_EXCEPT);
181	return (0);
182}
183
184#if __BSD_VISIBLE
185
186/* We currently provide no external definitions of the functions below. */
187
188static inline int
189feenableexcept(int __mask)
190{
191	fenv_t __old_fpsr, __new_fpsr;
192
193	__rfs(&__old_fpsr);
194	__new_fpsr = __old_fpsr | (__mask & FE_ALL_EXCEPT) << _FPUSW_SHIFT;
195	__wfs(__new_fpsr);
196	return ((__old_fpsr >> _FPUSW_SHIFT) & FE_ALL_EXCEPT);
197}
198
199static inline int
200fedisableexcept(int __mask)
201{
202	fenv_t __old_fpsr, __new_fpsr;
203
204	__rfs(&__old_fpsr);
205	__new_fpsr = __old_fpsr & ~((__mask & FE_ALL_EXCEPT) << _FPUSW_SHIFT);
206	__wfs(__new_fpsr);
207	return ((__old_fpsr >> _FPUSW_SHIFT) & FE_ALL_EXCEPT);
208}
209
210static inline int
211fegetexcept(void)
212{
213	fenv_t __fpsr;
214
215	__rfs(&__fpsr);
216	return ((__fpsr & _ENABLE_MASK) >> _FPUSW_SHIFT);
217}
218
219#endif /* __BSD_VISIBLE */
220
221__END_DECLS
222
223#endif	/* !_FENV_H_ */
224