xref: /freebsd/lib/msun/arm/fenv.h (revision 8881d206f4e68b564c2c5f50fc717086fc3e827a)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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  * $FreeBSD$
29  */
30 
31 #ifndef	_FENV_H_
32 #define	_FENV_H_
33 
34 #include <sys/_types.h>
35 
36 #ifndef	__fenv_static
37 #define	__fenv_static	static
38 #endif
39 
40 typedef	__uint32_t	fenv_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 /* We need to be able to map status flag positions to mask flag positions */
84 #ifndef __ARM_PCS_VFP
85 #define	_FPUSW_SHIFT	16
86 #define	_ENABLE_MASK	(FE_ALL_EXCEPT << _FPUSW_SHIFT)
87 #endif
88 
89 #ifndef __ARM_PCS_VFP
90 
91 int feclearexcept(int __excepts);
92 int fegetexceptflag(fexcept_t *__flagp, int __excepts);
93 int fesetexceptflag(const fexcept_t *__flagp, int __excepts);
94 int feraiseexcept(int __excepts);
95 int fetestexcept(int __excepts);
96 int fegetround(void);
97 int fesetround(int __round);
98 int fegetenv(fenv_t *__envp);
99 int feholdexcept(fenv_t *__envp);
100 int fesetenv(const fenv_t *__envp);
101 int feupdateenv(const fenv_t *__envp);
102 #if __BSD_VISIBLE
103 int feenableexcept(int __mask);
104 int fedisableexcept(int __mask);
105 int fegetexcept(void);
106 #endif
107 
108 #else	/* __ARM_PCS_VFP */
109 
110 #define	vmrs_fpscr(__r)	__asm __volatile("vmrs %0, fpscr" : "=&r"(__r))
111 #define	vmsr_fpscr(__r)	__asm __volatile("vmsr fpscr, %0" : : "r"(__r))
112 
113 #define _FPU_MASK_SHIFT	8
114 
115 __fenv_static inline int
116 feclearexcept(int __excepts)
117 {
118 	fexcept_t __fpsr;
119 
120 	vmrs_fpscr(__fpsr);
121 	__fpsr &= ~__excepts;
122 	vmsr_fpscr(__fpsr);
123 	return (0);
124 }
125 
126 __fenv_static inline int
127 fegetexceptflag(fexcept_t *__flagp, int __excepts)
128 {
129 	fexcept_t __fpsr;
130 
131 	vmrs_fpscr(__fpsr);
132 	*__flagp = __fpsr & __excepts;
133 	return (0);
134 }
135 
136 __fenv_static inline int
137 fesetexceptflag(const fexcept_t *__flagp, int __excepts)
138 {
139 	fexcept_t __fpsr;
140 
141 	vmrs_fpscr(__fpsr);
142 	__fpsr &= ~__excepts;
143 	__fpsr |= *__flagp & __excepts;
144 	vmsr_fpscr(__fpsr);
145 	return (0);
146 }
147 
148 __fenv_static inline int
149 feraiseexcept(int __excepts)
150 {
151 	fexcept_t __ex = __excepts;
152 
153 	fesetexceptflag(&__ex, __excepts);	/* XXX */
154 	return (0);
155 }
156 
157 __fenv_static inline int
158 fetestexcept(int __excepts)
159 {
160 	fexcept_t __fpsr;
161 
162 	vmrs_fpscr(__fpsr);
163 	return (__fpsr & __excepts);
164 }
165 
166 __fenv_static inline int
167 fegetround(void)
168 {
169 	fenv_t __fpsr;
170 
171 	vmrs_fpscr(__fpsr);
172 	return (__fpsr & _ROUND_MASK);
173 }
174 
175 __fenv_static inline int
176 fesetround(int __round)
177 {
178 	fenv_t __fpsr;
179 
180 	vmrs_fpscr(__fpsr);
181 	__fpsr &= ~(_ROUND_MASK);
182 	__fpsr |= __round;
183 	vmsr_fpscr(__fpsr);
184 	return (0);
185 }
186 
187 __fenv_static inline int
188 fegetenv(fenv_t *__envp)
189 {
190 
191 	vmrs_fpscr(*__envp);
192 	return (0);
193 }
194 
195 __fenv_static inline int
196 feholdexcept(fenv_t *__envp)
197 {
198 	fenv_t __env;
199 
200 	vmrs_fpscr(__env);
201 	*__envp = __env;
202 	__env &= ~(FE_ALL_EXCEPT);
203 	vmsr_fpscr(__env);
204 	return (0);
205 }
206 
207 __fenv_static inline int
208 fesetenv(const fenv_t *__envp)
209 {
210 
211 	vmsr_fpscr(*__envp);
212 	return (0);
213 }
214 
215 __fenv_static inline int
216 feupdateenv(const fenv_t *__envp)
217 {
218 	fexcept_t __fpsr;
219 
220 	vmrs_fpscr(__fpsr);
221 	vmsr_fpscr(*__envp);
222 	feraiseexcept(__fpsr & FE_ALL_EXCEPT);
223 	return (0);
224 }
225 
226 #if __BSD_VISIBLE
227 
228 /* We currently provide no external definitions of the functions below. */
229 
230 __fenv_static inline int
231 feenableexcept(int __mask)
232 {
233 	fenv_t __old_fpsr, __new_fpsr;
234 
235 	vmrs_fpscr(__old_fpsr);
236 	__new_fpsr = __old_fpsr |
237 	    ((__mask & FE_ALL_EXCEPT) << _FPU_MASK_SHIFT);
238 	vmsr_fpscr(__new_fpsr);
239 	return ((__old_fpsr >> _FPU_MASK_SHIFT) & FE_ALL_EXCEPT);
240 }
241 
242 __fenv_static inline int
243 fedisableexcept(int __mask)
244 {
245 	fenv_t __old_fpsr, __new_fpsr;
246 
247 	vmrs_fpscr(__old_fpsr);
248 	__new_fpsr = __old_fpsr &
249 	    ~((__mask & FE_ALL_EXCEPT) << _FPU_MASK_SHIFT);
250 	vmsr_fpscr(__new_fpsr);
251 	return ((__old_fpsr >> _FPU_MASK_SHIFT) & FE_ALL_EXCEPT);
252 }
253 
254 __fenv_static inline int
255 fegetexcept(void)
256 {
257 	fenv_t __fpsr;
258 
259 	vmrs_fpscr(__fpsr);
260 	return (__fpsr & FE_ALL_EXCEPT);
261 }
262 
263 #endif /* __BSD_VISIBLE */
264 
265 #endif	/* __ARM_PCS_VFP */
266 
267 __END_DECLS
268 
269 #endif	/* !_FENV_H_ */
270