xref: /freebsd/lib/msun/arm/fenv.h (revision 27c43fe1f3795622c5bd4bbfc465a29a800c0799)
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 #ifdef __ARM_PCS_VFP
48 #define	FE_DENORMAL	0x0080
49 #define	FE_ALL_EXCEPT	(FE_DIVBYZERO | FE_INEXACT | \
50 			 FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW | FE_DENORMAL)
51 #else
52 #define	FE_ALL_EXCEPT	(FE_DIVBYZERO | FE_INEXACT | \
53 			 FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW)
54 #endif
55 
56 /* Rounding modes */
57 #ifdef __ARM_PCS_VFP
58 #define	FE_TONEAREST	0x00000000
59 #define	FE_UPWARD	0x00400000
60 #define	FE_DOWNWARD	0x00800000
61 #define	FE_TOWARDZERO	0x00c00000
62 #else
63 #define	FE_TONEAREST	0x0000
64 #define	FE_TOWARDZERO	0x0001
65 #define	FE_UPWARD	0x0002
66 #define	FE_DOWNWARD	0x0003
67 #endif
68 #define	_ROUND_MASK	(FE_TONEAREST | FE_DOWNWARD | \
69 			 FE_UPWARD | FE_TOWARDZERO)
70 __BEGIN_DECLS
71 
72 /* Default floating-point environment */
73 extern const fenv_t	__fe_dfl_env;
74 #define	FE_DFL_ENV	(&__fe_dfl_env)
75 
76 /* We need to be able to map status flag positions to mask flag positions */
77 #ifndef __ARM_PCS_VFP
78 #define	_FPUSW_SHIFT	16
79 #define	_ENABLE_MASK	(FE_ALL_EXCEPT << _FPUSW_SHIFT)
80 #endif
81 
82 #ifndef __ARM_PCS_VFP
83 
84 int feclearexcept(int __excepts);
85 int fegetexceptflag(fexcept_t *__flagp, int __excepts);
86 int fesetexceptflag(const fexcept_t *__flagp, int __excepts);
87 int feraiseexcept(int __excepts);
88 int fetestexcept(int __excepts);
89 int fegetround(void);
90 int fesetround(int __round);
91 int fegetenv(fenv_t *__envp);
92 int feholdexcept(fenv_t *__envp);
93 int fesetenv(const fenv_t *__envp);
94 int feupdateenv(const fenv_t *__envp);
95 
96 #else	/* __ARM_PCS_VFP */
97 
98 #define	vmrs_fpscr(__r)	__asm __volatile("vmrs %0, fpscr" : "=&r"(__r))
99 #define	vmsr_fpscr(__r)	__asm __volatile("vmsr fpscr, %0" : : "r"(__r))
100 
101 #define _FPU_MASK_SHIFT	8
102 
103 __fenv_static inline int
104 feclearexcept(int __excepts)
105 {
106 	fexcept_t __fpsr;
107 
108 	vmrs_fpscr(__fpsr);
109 	__fpsr &= ~__excepts;
110 	vmsr_fpscr(__fpsr);
111 	return (0);
112 }
113 
114 __fenv_static inline int
115 fegetexceptflag(fexcept_t *__flagp, int __excepts)
116 {
117 	fexcept_t __fpsr;
118 
119 	vmrs_fpscr(__fpsr);
120 	*__flagp = __fpsr & __excepts;
121 	return (0);
122 }
123 
124 __fenv_static inline int
125 fesetexceptflag(const fexcept_t *__flagp, int __excepts)
126 {
127 	fexcept_t __fpsr;
128 
129 	vmrs_fpscr(__fpsr);
130 	__fpsr &= ~__excepts;
131 	__fpsr |= *__flagp & __excepts;
132 	vmsr_fpscr(__fpsr);
133 	return (0);
134 }
135 
136 __fenv_static inline int
137 feraiseexcept(int __excepts)
138 {
139 	fexcept_t __ex = __excepts;
140 
141 	fesetexceptflag(&__ex, __excepts);	/* XXX */
142 	return (0);
143 }
144 
145 __fenv_static inline int
146 fetestexcept(int __excepts)
147 {
148 	fexcept_t __fpsr;
149 
150 	vmrs_fpscr(__fpsr);
151 	return (__fpsr & __excepts);
152 }
153 
154 __fenv_static inline int
155 fegetround(void)
156 {
157 	fenv_t __fpsr;
158 
159 	vmrs_fpscr(__fpsr);
160 	return (__fpsr & _ROUND_MASK);
161 }
162 
163 __fenv_static inline int
164 fesetround(int __round)
165 {
166 	fenv_t __fpsr;
167 
168 	vmrs_fpscr(__fpsr);
169 	__fpsr &= ~(_ROUND_MASK);
170 	__fpsr |= __round;
171 	vmsr_fpscr(__fpsr);
172 	return (0);
173 }
174 
175 __fenv_static inline int
176 fegetenv(fenv_t *__envp)
177 {
178 
179 	vmrs_fpscr(*__envp);
180 	return (0);
181 }
182 
183 __fenv_static inline int
184 feholdexcept(fenv_t *__envp)
185 {
186 	fenv_t __env;
187 
188 	vmrs_fpscr(__env);
189 	*__envp = __env;
190 	__env &= ~(FE_ALL_EXCEPT);
191 	vmsr_fpscr(__env);
192 	return (0);
193 }
194 
195 __fenv_static inline int
196 fesetenv(const fenv_t *__envp)
197 {
198 
199 	vmsr_fpscr(*__envp);
200 	return (0);
201 }
202 
203 __fenv_static inline int
204 feupdateenv(const fenv_t *__envp)
205 {
206 	fexcept_t __fpsr;
207 
208 	vmrs_fpscr(__fpsr);
209 	vmsr_fpscr(*__envp);
210 	feraiseexcept(__fpsr & FE_ALL_EXCEPT);
211 	return (0);
212 }
213 
214 #if __BSD_VISIBLE
215 
216 /* We currently provide no external definitions of the functions below. */
217 
218 __fenv_static inline int
219 feenableexcept(int __mask)
220 {
221 	fenv_t __old_fpsr, __new_fpsr;
222 
223 	vmrs_fpscr(__old_fpsr);
224 	__new_fpsr = __old_fpsr |
225 	    ((__mask & FE_ALL_EXCEPT) << _FPU_MASK_SHIFT);
226 	vmsr_fpscr(__new_fpsr);
227 	return ((__old_fpsr >> _FPU_MASK_SHIFT) & FE_ALL_EXCEPT);
228 }
229 
230 __fenv_static inline int
231 fedisableexcept(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 fegetexcept(void)
244 {
245 	fenv_t __fpsr;
246 
247 	vmrs_fpscr(__fpsr);
248 	return (__fpsr & FE_ALL_EXCEPT);
249 }
250 
251 #endif /* __BSD_VISIBLE */
252 
253 #endif	/* __ARM_PCS_VFP */
254 
255 __END_DECLS
256 
257 #endif	/* !_FENV_H_ */
258