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 * $FreeBSD$
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
38 typedef __uint32_t fenv_t;
39 typedef __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 */
60 extern 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
feclearexcept(int __excepts)76 feclearexcept(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
fegetexceptflag(fexcept_t * __flagp,int __excepts)87 fegetexceptflag(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
fesetexceptflag(const fexcept_t * __flagp,int __excepts)97 fesetexceptflag(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
feraiseexcept(int __excepts)109 feraiseexcept(int __excepts)
110 {
111 fexcept_t __ex = __excepts;
112
113 fesetexceptflag(&__ex, __excepts); /* XXX */
114 return (0);
115 }
116
117 __fenv_static inline int
fetestexcept(int __excepts)118 fetestexcept(int __excepts)
119 {
120 fexcept_t __fpsr;
121
122 __rfs(&__fpsr);
123 return (__fpsr & __excepts);
124 }
125
126 __fenv_static inline int
fegetround(void)127 fegetround(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
fesetround(int __round)139 fesetround(int __round)
140 {
141
142 return (-1);
143 }
144
145 __fenv_static inline int
fegetenv(fenv_t * __envp)146 fegetenv(fenv_t *__envp)
147 {
148
149 __rfs(__envp);
150 return (0);
151 }
152
153 __fenv_static inline int
feholdexcept(fenv_t * __envp)154 feholdexcept(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
fesetenv(const fenv_t * __envp)166 fesetenv(const fenv_t *__envp)
167 {
168
169 __wfs(*__envp);
170 return (0);
171 }
172
173 __fenv_static inline int
feupdateenv(const fenv_t * __envp)174 feupdateenv(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
188 static inline int
feenableexcept(int __mask)189 feenableexcept(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
199 static inline int
fedisableexcept(int __mask)200 fedisableexcept(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
210 static inline int
fegetexcept(void)211 fegetexcept(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