xref: /freebsd/lib/msun/arm/fenv.h (revision 9aff62dee28239f84b4aa4a3429cf26dbbf770cc)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2004-2005 David Schultz <das@FreeBSD.ORG>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #ifndef	_FENV_H_
30 #define	_FENV_H_
31 
32 #include <sys/cdefs.h>
33 #include <sys/_types.h>
34 
35 #ifndef	__fenv_static
36 #define	__fenv_static	static
37 #endif
38 
39 typedef	__uint32_t	fenv_t;
40 typedef	__uint32_t	femode_t;
41 typedef	__uint32_t	fexcept_t;
42 
43 /* Exception flags */
44 #define	FE_INVALID	0x0001
45 #define	FE_DIVBYZERO	0x0002
46 #define	FE_OVERFLOW	0x0004
47 #define	FE_UNDERFLOW	0x0008
48 #define	FE_INEXACT	0x0010
49 #ifdef __ARM_PCS_VFP
50 #define	FE_DENORMAL	0x0080
51 #define	FE_ALL_EXCEPT	(FE_DIVBYZERO | FE_INEXACT | \
52 			 FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW | FE_DENORMAL)
53 #else
54 #define	FE_ALL_EXCEPT	(FE_DIVBYZERO | FE_INEXACT | \
55 			 FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW)
56 #endif
57 
58 /* Rounding modes */
59 #define	VFP_FE_TONEAREST	0x00000000
60 #define	VFP_FE_UPWARD		0x00400000
61 #define	VFP_FE_DOWNWARD		0x00800000
62 #define	VFP_FE_TOWARDZERO	0x00c00000
63 
64 #ifdef __ARM_PCS_VFP
65 #define	FE_TONEAREST	VFP_FE_TONEAREST
66 #define	FE_UPWARD	VFP_FE_UPWARD
67 #define	FE_DOWNWARD	VFP_FE_DOWNWARD
68 #define	FE_TOWARDZERO	VFP_FE_TOWARDZERO
69 #else
70 #define	FE_TONEAREST	0x0000
71 #define	FE_TOWARDZERO	0x0001
72 #define	FE_UPWARD	0x0002
73 #define	FE_DOWNWARD	0x0003
74 #endif
75 #define	_ROUND_MASK	(FE_TONEAREST | FE_DOWNWARD | \
76 			 FE_UPWARD | FE_TOWARDZERO)
77 __BEGIN_DECLS
78 
79 /* Default floating-point environment */
80 extern const fenv_t	__fe_dfl_env;
81 #define	FE_DFL_ENV	(&__fe_dfl_env)
82 
83 /* Default floating-point control modes */
84 extern const femode_t	__fe_dfl_mode;
85 #define	FE_DFL_MODE	(&__fe_dfl_mode)
86 
87 /* We need to be able to map status flag positions to mask flag positions */
88 #ifndef __ARM_PCS_VFP
89 #define	_FPUSW_SHIFT	16
90 #define	_ENABLE_MASK	(FE_ALL_EXCEPT << _FPUSW_SHIFT)
91 #endif
92 
93 #ifndef __ARM_PCS_VFP
94 
95 int feclearexcept(int __excepts);
96 int fegetexceptflag(fexcept_t *__flagp, int __excepts);
97 int fesetexceptflag(const fexcept_t *__flagp, int __excepts);
98 int feraiseexcept(int __excepts);
99 int fetestexcept(int __excepts);
100 int fegetround(void);
101 int fesetround(int __round);
102 int fegetmode(femode_t *__modep);
103 int fesetmode(const femode_t *__modep);
104 int fegetenv(fenv_t *__envp);
105 int feholdexcept(fenv_t *__envp);
106 int fesetenv(const fenv_t *__envp);
107 int feupdateenv(const fenv_t *__envp);
108 #if __BSD_VISIBLE
109 int feenableexcept(int __mask);
110 int fedisableexcept(int __mask);
111 int fegetexcept(void);
112 #endif
113 
114 #else	/* __ARM_PCS_VFP */
115 
116 #define	vmrs_fpscr(__r)	__asm __volatile("vmrs %0, fpscr" : "=&r"(__r))
117 #define	vmsr_fpscr(__r)	__asm __volatile("vmsr fpscr, %0" : : "r"(__r))
118 
119 #define _FPU_MASK_SHIFT	8
120 
121 int feclearexcept(int);
122 int fegetexceptflag(fexcept_t *, int);
123 int fesetexceptflag(const fexcept_t *, int);
124 int feraiseexcept(int);
125 int fetestexcept(int);
126 int fegetround(void);
127 int fesetround(int);
128 int fegetmode(femode_t *);
129 int fesetmode(const femode_t *);
130 int fegetenv(fenv_t *);
131 int feholdexcept(fenv_t *);
132 int fesetenv(const fenv_t *);
133 int feupdateenv(const fenv_t *);
134 int fegetexcept(void);
135 #if __BSD_VISIBLE
136 int feenableexcept(int);
137 int fedisableexcept(int);
138 int fegetexcept(void);
139 #endif
140 
141 /*
142  * C permits a standard library function to also be exposed as a function-like
143  * macro (C23 7.1.4), and msun uses that here to inline the fast path.  C++
144  * forbids it: <cfenv> imports these names into namespace std (using
145  * ::feclearexcept; etc.), so std::feclearexcept() and friends must denote the
146  * actual functions.  Expose the inlining macros to C only; C++ uses the real
147  * extern functions (defined in the matching lib/msun/<arch>/fenv.c).
148  */
149 #ifndef __cplusplus
150 #define	feclearexcept(a)	__feclearexcept_int(a)
151 #define	fegetexceptflag(e, a)	__fegetexceptflag_int(e, a)
152 #define	fesetexceptflag(e, a)	__fesetexceptflag_int(e, a)
153 #define	feraiseexcept(a)	__feraiseexcept_int(a)
154 #define	fetestexcept(a)		__fetestexcept_int(a)
155 #define	fegetround()		__fegetround_int()
156 #define	fesetround(a)		__fesetround_int(a)
157 #define	fegetmode(m)		__fegetmode_int(m)
158 #define	fesetmode(m)		__fesetmode_int(m)
159 #define	fegetenv(e)		__fegetenv_int(e)
160 #define	feholdexcept(e)		__feholdexcept_int(e)
161 #define	fesetenv(e)		__fesetenv_int(e)
162 #define	feupdateenv(e)		__feupdateenv_int(e)
163 #if __BSD_VISIBLE
164 #define	feenableexcept(a)	__feenableexcept_int(a)
165 #define	fedisableexcept(a)	__fedisableexcept_int(a)
166 #define	fegetexcept()		__fegetexcept_int()
167 #endif
168 #endif /* !__cplusplus */
169 
170 __fenv_static inline int
171 __feclearexcept_int(int __excepts)
172 {
173 	fexcept_t __fpsr;
174 
175 	vmrs_fpscr(__fpsr);
176 	__fpsr &= ~__excepts;
177 	vmsr_fpscr(__fpsr);
178 	return (0);
179 }
180 
181 __fenv_static inline int
182 __fegetexceptflag_int(fexcept_t *__flagp, int __excepts)
183 {
184 	fexcept_t __fpsr;
185 
186 	vmrs_fpscr(__fpsr);
187 	*__flagp = __fpsr & __excepts;
188 	return (0);
189 }
190 
191 __fenv_static inline int
192 __fesetexceptflag_int(const fexcept_t *__flagp, int __excepts)
193 {
194 	fexcept_t __fpsr;
195 
196 	vmrs_fpscr(__fpsr);
197 	__fpsr &= ~__excepts;
198 	__fpsr |= *__flagp & __excepts;
199 	vmsr_fpscr(__fpsr);
200 	return (0);
201 }
202 
203 __fenv_static inline int
204 __feraiseexcept_int(int __excepts)
205 {
206 	fexcept_t __ex = __excepts;
207 
208 	fesetexceptflag(&__ex, __excepts);	/* XXX */
209 	return (0);
210 }
211 
212 __fenv_static inline int
213 __fetestexcept_int(int __excepts)
214 {
215 	fexcept_t __fpsr;
216 
217 	vmrs_fpscr(__fpsr);
218 	return (__fpsr & __excepts);
219 }
220 
221 __fenv_static inline int
222 __fegetround_int(void)
223 {
224 	fenv_t __fpsr;
225 
226 	vmrs_fpscr(__fpsr);
227 	return (__fpsr & _ROUND_MASK);
228 }
229 
230 __fenv_static inline int
231 __fesetround_int(int __round)
232 {
233 	fenv_t __fpsr;
234 
235 	vmrs_fpscr(__fpsr);
236 	__fpsr &= ~(_ROUND_MASK);
237 	__fpsr |= __round;
238 	vmsr_fpscr(__fpsr);
239 	return (0);
240 }
241 
242 __fenv_static inline int
243 __fegetmode_int(femode_t *__modep)
244 {
245 	fenv_t __fpsr;
246 
247 	vmrs_fpscr(__fpsr);
248 	*__modep = __fpsr & ~FE_ALL_EXCEPT;
249 	return (0);
250 }
251 
252 __fenv_static inline int
253 __fesetmode_int(const femode_t *__modep)
254 {
255 	fenv_t __fpsr;
256 
257 	vmrs_fpscr(__fpsr);
258 	__fpsr &= FE_ALL_EXCEPT;
259 	__fpsr |= *__modep & ~FE_ALL_EXCEPT;
260 	vmsr_fpscr(__fpsr);
261 	return (0);
262 }
263 
264 __fenv_static inline int
265 __fegetenv_int(fenv_t *__envp)
266 {
267 
268 	vmrs_fpscr(*__envp);
269 	return (0);
270 }
271 
272 __fenv_static inline int
273 __feholdexcept_int(fenv_t *__envp)
274 {
275 	fenv_t __env;
276 
277 	vmrs_fpscr(__env);
278 	*__envp = __env;
279 	__env &= ~(FE_ALL_EXCEPT);
280 	vmsr_fpscr(__env);
281 	return (0);
282 }
283 
284 __fenv_static inline int
285 __fesetenv_int(const fenv_t *__envp)
286 {
287 
288 	vmsr_fpscr(*__envp);
289 	return (0);
290 }
291 
292 __fenv_static inline int
293 __feupdateenv_int(const fenv_t *__envp)
294 {
295 	fexcept_t __fpsr;
296 
297 	vmrs_fpscr(__fpsr);
298 	vmsr_fpscr(*__envp);
299 	feraiseexcept(__fpsr & FE_ALL_EXCEPT);
300 	return (0);
301 }
302 
303 #if __BSD_VISIBLE
304 
305 /* We currently provide no external definitions of the functions below. */
306 
307 __fenv_static inline int
308 __feenableexcept_int(int __mask)
309 {
310 	fenv_t __old_fpsr, __new_fpsr;
311 
312 	vmrs_fpscr(__old_fpsr);
313 	__new_fpsr = __old_fpsr |
314 	    ((__mask & FE_ALL_EXCEPT) << _FPU_MASK_SHIFT);
315 	vmsr_fpscr(__new_fpsr);
316 	return ((__old_fpsr >> _FPU_MASK_SHIFT) & FE_ALL_EXCEPT);
317 }
318 
319 __fenv_static inline int
320 __fedisableexcept_int(int __mask)
321 {
322 	fenv_t __old_fpsr, __new_fpsr;
323 
324 	vmrs_fpscr(__old_fpsr);
325 	__new_fpsr = __old_fpsr &
326 	    ~((__mask & FE_ALL_EXCEPT) << _FPU_MASK_SHIFT);
327 	vmsr_fpscr(__new_fpsr);
328 	return ((__old_fpsr >> _FPU_MASK_SHIFT) & FE_ALL_EXCEPT);
329 }
330 
331 __fenv_static inline int
332 __fegetexcept_int(void)
333 {
334 	fenv_t __fpsr;
335 
336 	vmrs_fpscr(__fpsr);
337 	return (__fpsr & FE_ALL_EXCEPT);
338 }
339 
340 #endif /* __BSD_VISIBLE */
341 
342 #endif	/* __ARM_PCS_VFP */
343 
344 __END_DECLS
345 
346 #endif	/* !_FENV_H_ */
347