xref: /netbsd-src/sys/arch/m68k/include/fenv.h (revision 82d56013d7b633d116a93943de88e08335357a7c)
1 /*	$NetBSD: fenv.h,v 1.8 2019/10/26 17:51:49 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 2015 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Christos Zoulas.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #ifndef _M68K_FENV_H_
33 #define _M68K_FENV_H_
34 
35 #include <sys/stdint.h>
36 #include <m68k/float.h>
37 #include <m68k/fpreg.h>
38 
39 /* Exception bits, from FPSR */
40 #define	FE_INEXACT	FPSR_AINEX
41 #define	FE_DIVBYZERO	FPSR_ADZ
42 #define	FE_UNDERFLOW	FPSR_AUNFL
43 #define	FE_OVERFLOW	FPSR_AOVFL
44 #define	FE_INVALID	FPSR_AIOP
45 
46 #define FE_ALL_EXCEPT \
47     (FE_INEXACT | FE_DIVBYZERO | FE_UNDERFLOW | FE_OVERFLOW | FE_INVALID)
48 
49 /* Rounding modes, from FPCR */
50 #define FE_TONEAREST	FPCR_NEAR
51 #define	FE_TOWARDZERO	FPCR_ZERO
52 #define	FE_DOWNWARD	FPCR_MINF
53 #define	FE_UPWARD	FPCR_PINF
54 
55 #define _ROUND_MASK	\
56     (FE_TONEAREST | FE_TOWARDZERO | FE_DOWNWARD | FE_UPWARD)
57 
58 #if defined(__HAVE_68881__)
59 
60 #ifndef __fenv_static
61 #define __fenv_static   static
62 #endif
63 
64 typedef uint32_t fexcept_t;
65 
66 /* same layout as fmovem */
67 typedef struct {
68 	uint32_t fpcr;
69 	uint32_t fpsr;
70 	uint32_t fppc;
71 } fenv_t;
72 
73 #define FE_DFL_ENV	((fenv_t *) -1)
74 
75 #define __get_fpcr(__fpcr) \
76     __asm__ __volatile__ ("fmove%.l %!,%0" : "=dm" (__fpcr))
77 #define __set_fpcr(__fpcr) \
78     __asm__ __volatile__ ("fmove%.l %0,%!" : : "dm" (__fpcr))
79 
80 #define __get_fpsr(__fpsr) \
81     __asm__ __volatile__ ("fmove%.l %/fpsr,%0" : "=dm" (__fpsr))
82 #define __set_fpsr(__fpsr) \
83     __asm__ __volatile__ ("fmove%.l %0,%/fpsr" : : "dm" (__fpsr))
84 
85 #define __fmul(__s, __t, __d) \
86     do { \
87 	    __t d = __d; \
88 	    __asm__ __volatile__ ("fmul" __s "; fnop" : "=f" (d) : "0" (d)); \
89     } while (/*CONSTCOND*/0)
90 
91 #define __fdiv(__s, __t, __d) \
92     do { \
93 	    __t d = __d; \
94 	    __asm__ __volatile__ ("fdiv" __s "; fnop" : "=f" (d) : "0" (d)); \
95     } while (/*CONSTCOND*/0)
96 
97 #define __fetox(__s, __t, __d) \
98     do { \
99 	    __t d = __d; \
100 	    __asm__ __volatile__ ("fetox" __s "; fnop" : "=f" (d) : "0" (d)); \
101     } while (/*CONSTCOND*/0)
102 
103 #define __fgetenv(__envp) \
104     __asm__ __volatile__ ("fmovem%.l %/fpcr/%/fpsr/%/fpiar,%0" : "=m" (__envp))
105 
106 #define __fsetenv(__envp) \
107     __asm__ __volatile__ ("fmovem%.l %0,%/fpcr/%/fpsr/%/fpiar" : : "m" (__envp))
108 
109 __BEGIN_DECLS
110 
111 #if __GNUC_PREREQ__(8, 0)
112 #pragma GCC diagnostic push
113 #pragma GCC diagnostic ignored "-Wshadow"
114 #endif
115 
116 __fenv_static inline int
117 feclearexcept(int __excepts)
118 {
119 	fexcept_t __fpsr;
120 
121 	__excepts &= FE_ALL_EXCEPT;
122 
123 	__get_fpsr(__fpsr);
124 	__fpsr &= ~__excepts;
125 	__set_fpsr(__fpsr);
126 
127 	return 0;
128 }
129 
130 __fenv_static inline int
131 fegetexceptflag(fexcept_t *__flagp, int __excepts)
132 {
133 	fexcept_t __fpsr;
134 
135 	__get_fpsr(__fpsr);
136 
137 	*__flagp = __fpsr & __excepts & FE_ALL_EXCEPT;
138 
139 	return 0;
140 }
141 
142 __fenv_static inline int
143 fesetexceptflag(const fexcept_t *__flagp, int __excepts)
144 {
145 	fexcept_t __fpsr;
146 
147 	__get_fpsr(__fpsr);
148 
149 	__fpsr &= ~(__excepts & FE_ALL_EXCEPT);
150 	__fpsr |= *__flagp & __excepts & FE_ALL_EXCEPT;
151 
152 	__set_fpsr(__fpsr);
153 
154 	return 0;
155 }
156 
157 __fenv_static inline int
158 feraiseexcept(int __excepts)
159 {
160 	if (__excepts & FE_INVALID)	/* Inf * 0 */
161 		__fmul("%.s %#0r0,%0", double, __builtin_huge_val());
162 
163 	if (__excepts & FE_DIVBYZERO)	/* 1.0 / 0 */
164 		__fdiv("%.s %#0r0,%0", double, 1.0);
165 
166 	if (__excepts & FE_OVERFLOW)	/* MAX * MAX */
167 		__fmul("%.x %0,%0", long double, LDBL_MAX);
168 
169 	if (__excepts & FE_UNDERFLOW)	/* e ^ -MAX */
170 		__fetox("%.x %0", long double, -LDBL_MAX);
171 
172 	if (__excepts & FE_INEXACT)	/* 1 / 3 */
173 		__fdiv("%.s %#0r3,%0", long double, 1.0);
174 
175 	return 0;
176 }
177 
178 __fenv_static inline int
179 fetestexcept(int __excepts)
180 {
181 	fexcept_t __fpsr;
182 
183 	__get_fpsr(__fpsr);
184 
185 	return __fpsr & __excepts & FE_ALL_EXCEPT;
186 }
187 
188 __fenv_static inline int
189 fegetround(void)
190 {
191 	fexcept_t __fpcr;
192 
193 	__get_fpcr(__fpcr);
194 	return __fpcr & _ROUND_MASK;
195 }
196 
197 __fenv_static inline int
198 fesetround(int __round)
199 {
200 	fexcept_t __fpcr;
201 
202 	if (__round & ~_ROUND_MASK)
203 		return -1;
204 
205 	__get_fpcr(__fpcr);
206 
207 	__fpcr &= ~_ROUND_MASK;
208 	__fpcr |= __round;
209 
210 	__set_fpcr(__fpcr);
211 
212 	return 0;
213 }
214 
215 __fenv_static inline int
216 fegetenv(fenv_t *__envp)
217 {
218 	__fgetenv(*__envp);
219 
220 	return 0;
221 }
222 
223 __fenv_static inline int
224 feholdexcept(fenv_t *__envp)
225 {
226 	fexcept_t __fpcr, __fpsr;
227 
228 	__fgetenv(*__envp);
229 	__fpsr = __envp->fpsr & ~FE_ALL_EXCEPT;
230 	__set_fpsr(__fpsr);	/* clear all */
231 	__fpcr = __envp->fpcr & ~(FE_ALL_EXCEPT << 6);
232 	__set_fpcr(__fpcr);	/* set non/stop */
233 
234 	return 0;
235 }
236 
237 __fenv_static inline int
238 fesetenv(const fenv_t *__envp)
239 {
240 	fenv_t __tenv;
241 
242 	__fgetenv(__tenv);
243 
244 	if (__envp == FE_DFL_ENV) {
245 		__tenv.fpcr |=
246 		    __envp->fpcr & ((FE_ALL_EXCEPT << 6) | FE_UPWARD);
247 		__tenv.fpsr |= __envp->fpsr & FE_ALL_EXCEPT;
248 	}
249 
250 	__fsetenv(__tenv);
251 
252 	return 0;
253 }
254 
255 __fenv_static inline int
256 feupdateenv(const fenv_t *__envp)
257 {
258 	fexcept_t __fpsr;
259 
260 	__get_fpsr(__fpsr);
261 	__fpsr &= FE_ALL_EXCEPT;
262 	fesetenv(__envp);
263 	feraiseexcept((int)__fpsr);
264 	return 0;
265 }
266 
267 #if __GNUC_PREREQ__(8, 0)
268 #pragma GCC diagnostic pop
269 #endif
270 
271 #if defined(_NETBSD_SOURCE) || defined(_GNU_SOURCE)
272 
273 __fenv_static inline int
274 feenableexcept(int __mask)
275 {
276 	fexcept_t __fpcr, __oldmask;
277 
278 	__get_fpcr(__fpcr);
279 	__oldmask = (__fpcr >> 6) & FE_ALL_EXCEPT;
280 	__fpcr |= (__mask & FE_ALL_EXCEPT) << 6;
281 	__set_fpcr(__fpcr);
282 
283 	return __oldmask;
284 }
285 
286 __fenv_static inline int
287 fedisableexcept(int __mask)
288 {
289 	fexcept_t __fpcr, __oldmask;
290 
291 	__get_fpcr(__fpcr);
292 	__oldmask = (__fpcr >> 6) & FE_ALL_EXCEPT;
293 	__fpcr &= ~((__mask & FE_ALL_EXCEPT) << 6);
294 	__set_fpcr(__fpcr);
295 
296 	return __oldmask;
297 }
298 
299 __fenv_static inline int
300 fegetexcept(void)
301 {
302 	fexcept_t __fpcr;
303 
304 	__get_fpcr(__fpcr);
305 
306 	return (__fpcr >> 6) & FE_ALL_EXCEPT;
307 }
308 
309 #endif /* _NETBSD_SOURCE || _GNU_SOURCE */
310 
311 __END_DECLS
312 
313 #endif /* __HAVE_68881__ */
314 
315 #endif /* _M68K_FENV_H_ */
316