xref: /netbsd-src/sys/arch/powerpc/include/fenv.h (revision ccd9df534e375a4366c5b55f23782053c7a98d82)
1 /*	$NetBSD: fenv.h,v 1.7 2022/09/13 01:22:12 rin Exp $	*/
2 
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: head/lib/msun/powerpc/fenv.h 226218 2011-10-10 15:43:09Z das $
29  */
30 
31 #ifndef	_POWERPC_FENV_H_
32 #define	_POWERPC_FENV_H_
33 
34 #include <sys/stdint.h>
35 
36 /* Exception flags */
37 #define	FE_INEXACT	0x02000000
38 #define	FE_DIVBYZERO	0x04000000
39 #define	FE_UNDERFLOW	0x08000000
40 #define	FE_OVERFLOW	0x10000000
41 #define	FE_INVALID	0x20000000	/* all types of invalid FP ops */
42 
43 /*
44  * The PowerPC architecture has extra invalid flags that indicate the
45  * specific type of invalid operation occurred.  These flags may be
46  * tested, set, and cleared---but not masked---separately.  All of
47  * these bits are cleared when FE_INVALID is cleared, but only
48  * FE_VXSOFT is set when FE_INVALID is explicitly set in software.
49  */
50 #define	FE_VXCVI	0x00000100	/* invalid integer convert */
51 #define	FE_VXSQRT	0x00000200	/* square root of a negative */
52 #define	FE_VXSOFT	0x00000400	/* software-requested exception */
53 #define	FE_VXVC		0x00080000	/* ordered comparison involving NaN */
54 #define	FE_VXIMZ	0x00100000	/* inf * 0 */
55 #define	FE_VXZDZ	0x00200000	/* 0 / 0 */
56 #define	FE_VXIDI	0x00400000	/* inf / inf */
57 #define	FE_VXISI	0x00800000	/* inf - inf */
58 #define	FE_VXSNAN	0x01000000	/* operation on a signalling NaN */
59 #define	FE_ALL_INVALID	(FE_VXCVI | FE_VXSQRT | FE_VXSOFT | FE_VXVC | \
60 			 FE_VXIMZ | FE_VXZDZ | FE_VXIDI | FE_VXISI | \
61 			 FE_VXSNAN | FE_INVALID)
62 #define	FE_ALL_EXCEPT	(FE_DIVBYZERO | FE_INEXACT | \
63 			 FE_ALL_INVALID | FE_OVERFLOW | FE_UNDERFLOW)
64 
65 /* Rounding modes */
66 #define	FE_TONEAREST	0x0000
67 #define	FE_TOWARDZERO	0x0001
68 #define	FE_UPWARD	0x0002
69 #define	FE_DOWNWARD	0x0003
70 #define	_ROUND_MASK	(FE_TONEAREST | FE_DOWNWARD | \
71 			 FE_UPWARD | FE_TOWARDZERO)
72 
73 #ifndef _SOFT_FLOAT
74 
75 #ifndef	__fenv_static
76 #define	__fenv_static	static
77 #endif
78 
79 typedef	uint32_t	fenv_t;
80 typedef	uint32_t	fexcept_t;
81 
82 #ifndef _KERNEL
83 __BEGIN_DECLS
84 
85 /* Default floating-point environment */
86 extern const fenv_t	__fe_dfl_env;
87 #define	FE_DFL_ENV	(&__fe_dfl_env)
88 
89 /* We need to be able to map status flag positions to mask flag positions */
90 #define	_FPUSW_SHIFT	22
91 #define	_ENABLE_MASK	((FE_DIVBYZERO | FE_INEXACT | FE_INVALID | \
92 			 FE_OVERFLOW | FE_UNDERFLOW) >> _FPUSW_SHIFT)
93 
94 #ifndef _SOFT_FLOAT
95 #define	__mffs(__env)	__asm __volatile("mffs %0" : "=f" (*(__env)))
96 #define	__mtfsf(__env)	__asm __volatile("mtfsf 255,%0" : : "f" (__env))
97 
98 static __inline uint32_t
99 __mfmsr(void)
100 {
101 	uint32_t __msr;
102 
103 	__asm volatile ("mfmsr %0" : "=r"(__msr));
104 	return __msr;
105 }
106 
107 static __inline void
108 __mtmsr(uint32_t __msr)
109 {
110 
111 	__asm volatile ("mtmsr %0" : : "r"(__msr));
112 }
113 
114 #define __MSR_FE_MASK	(0x00000800 | 0x00000100)
115 #define __MSR_FE_DIS	(0)
116 #define __MSR_FE_PREC	(0x00000800 | 0x00000100)
117 
118 static __inline void
119 __updatemsr(uint32_t __reg)
120 {
121 	uint32_t __msr;
122 
123 	__msr = __mfmsr() & ~__MSR_FE_MASK;
124 	if (__reg != 0) {
125 		__msr |= __MSR_FE_PREC;
126 	} else {
127 		__msr |= __MSR_FE_DIS;
128 	}
129 	__mtmsr(__msr);
130 }
131 
132 #else
133 #define	__mffs(__env)
134 #define	__mtfsf(__env)
135 #define __updatemsr(__reg)
136 #endif
137 
138 union __fpscr {
139 	double __d;
140 	struct {
141 		uint32_t __junk;
142 		fenv_t __reg;
143 	} __bits;
144 };
145 
146 #if __GNUC_PREREQ__(8, 0)
147 #pragma GCC diagnostic push
148 #pragma GCC diagnostic ignored "-Wshadow"
149 #endif
150 
151 __fenv_static __inline int
152 feclearexcept(int __excepts)
153 {
154 	union __fpscr __r;
155 
156 	if (__excepts & FE_INVALID)
157 		__excepts |= FE_ALL_INVALID;
158 	__mffs(&__r.__d);
159 	__r.__bits.__reg &= ~__excepts;
160 	__mtfsf(__r.__d);
161 	return (0);
162 }
163 
164 __fenv_static __inline int
165 fegetexceptflag(fexcept_t *__flagp, int __excepts)
166 {
167 	union __fpscr __r;
168 
169 	__mffs(&__r.__d);
170 	*__flagp = __r.__bits.__reg & __excepts;
171 	return (0);
172 }
173 
174 __fenv_static __inline int
175 fesetexceptflag(const fexcept_t *__flagp, int __excepts)
176 {
177 	union __fpscr __r;
178 
179 	if (__excepts & FE_INVALID)
180 		__excepts |= FE_ALL_INVALID;
181 	__mffs(&__r.__d);
182 	__r.__bits.__reg &= ~__excepts;
183 	__r.__bits.__reg |= *__flagp & __excepts;
184 	__mtfsf(__r.__d);
185 	return (0);
186 }
187 
188 __fenv_static __inline int
189 feraiseexcept(int __excepts)
190 {
191 	union __fpscr __r;
192 
193 	if (__excepts & FE_INVALID)
194 		__excepts |= FE_VXSOFT;
195 	__mffs(&__r.__d);
196 	__r.__bits.__reg |= __excepts;
197 	__mtfsf(__r.__d);
198 	return (0);
199 }
200 
201 __fenv_static __inline int
202 fetestexcept(int __excepts)
203 {
204 	union __fpscr __r;
205 
206 	__mffs(&__r.__d);
207 	return (__r.__bits.__reg & __excepts);
208 }
209 
210 __fenv_static __inline int
211 fegetround(void)
212 {
213 	union __fpscr __r;
214 
215 	__mffs(&__r.__d);
216 	return (__r.__bits.__reg & _ROUND_MASK);
217 }
218 
219 __fenv_static __inline int
220 fesetround(int __round)
221 {
222 	union __fpscr __r;
223 
224 	if (__round & ~_ROUND_MASK)
225 		return (-1);
226 	__mffs(&__r.__d);
227 	__r.__bits.__reg &= ~_ROUND_MASK;
228 	__r.__bits.__reg |= __round;
229 	__mtfsf(__r.__d);
230 	return (0);
231 }
232 
233 __fenv_static __inline int
234 fegetenv(fenv_t *__envp)
235 {
236 	union __fpscr __r;
237 
238 	__mffs(&__r.__d);
239 	*__envp = __r.__bits.__reg;
240 	return (0);
241 }
242 
243 __fenv_static __inline int
244 feholdexcept(fenv_t *__envp)
245 {
246 	union __fpscr __r;
247 	uint32_t msr;
248 
249 	__mffs(&__r.__d);
250 	*__envp = __r.__bits.__reg;
251 	__r.__bits.__reg &= ~(FE_ALL_EXCEPT | _ENABLE_MASK);
252 	__mtfsf(__r.__d);
253 	__updatemsr(__r.__bits.__reg);
254 	return (0);
255 }
256 
257 __fenv_static __inline int
258 fesetenv(const fenv_t *__envp)
259 {
260 	union __fpscr __r;
261 
262 	__r.__bits.__reg = *__envp;
263 	__mtfsf(__r.__d);
264 	__updatemsr(__r.__bits.__reg);
265 	return (0);
266 }
267 
268 __fenv_static __inline int
269 feupdateenv(const fenv_t *__envp)
270 {
271 	union __fpscr __r;
272 
273 	__mffs(&__r.__d);
274 	__r.__bits.__reg &= FE_ALL_EXCEPT;
275 	__r.__bits.__reg |= *__envp;
276 	__mtfsf(__r.__d);
277 	__updatemsr(__r.__bits.__reg);
278 	return (0);
279 }
280 
281 #if __GNUC_PREREQ__(8, 0)
282 #pragma GCC diagnostic pop
283 #endif
284 
285 #if defined(_NETBSD_SOURCE) || defined(_GNU_SOURCE)
286 
287 __fenv_static __inline int
288 feenableexcept(int __mask)
289 {
290 	union __fpscr __r;
291 	fenv_t __oldmask;
292 
293 	__mffs(&__r.__d);
294 	__oldmask = __r.__bits.__reg;
295 	__r.__bits.__reg |= (__mask & FE_ALL_EXCEPT) >> _FPUSW_SHIFT;
296 	__mtfsf(__r.__d);
297 	__updatemsr(__r.__bits.__reg);
298 	return ((__oldmask & _ENABLE_MASK) << _FPUSW_SHIFT);
299 }
300 
301 __fenv_static __inline int
302 fedisableexcept(int __mask)
303 {
304 	union __fpscr __r;
305 	fenv_t __oldmask;
306 
307 	__mffs(&__r.__d);
308 	__oldmask = __r.__bits.__reg;
309 	__r.__bits.__reg &= ~((__mask & FE_ALL_EXCEPT) >> _FPUSW_SHIFT);
310 	__mtfsf(__r.__d);
311 	__updatemsr(__r.__bits.__reg);
312 	return ((__oldmask & _ENABLE_MASK) << _FPUSW_SHIFT);
313 }
314 
315 __fenv_static __inline int
316 fegetexcept(void)
317 {
318 	union __fpscr __r;
319 
320 	__mffs(&__r.__d);
321 	return ((__r.__bits.__reg & _ENABLE_MASK) << _FPUSW_SHIFT);
322 }
323 
324 #endif /* _NETBSD_SOURCE || _GNU_SOURCE */
325 
326 __END_DECLS
327 
328 #endif
329 #endif	/* _SOFT_FLOAT */
330 
331 #endif	/* !_POWERPC_FENV_H_ */
332