xref: /netbsd-src/sys/arch/m68k/include/fenv.h (revision b2a8932dbe9fdfd3d41d60d0a04b9a3ba294763d)
1 /*	$NetBSD: fenv.h,v 1.7 2017/09/13 09:55:35 phx 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 __fenv_static inline int
112 feclearexcept(int __excepts)
113 {
114 	fexcept_t __fpsr;
115 
116 	__excepts &= FE_ALL_EXCEPT;
117 
118 	__get_fpsr(__fpsr);
119 	__fpsr &= ~__excepts;
120 	__set_fpsr(__fpsr);
121 
122 	return 0;
123 }
124 
125 __fenv_static inline int
126 fegetexceptflag(fexcept_t *__flagp, int __excepts)
127 {
128 	fexcept_t __fpsr;
129 
130 	__get_fpsr(__fpsr);
131 
132 	*__flagp = __fpsr & __excepts & FE_ALL_EXCEPT;
133 
134 	return 0;
135 }
136 
137 __fenv_static inline int
138 fesetexceptflag(const fexcept_t *__flagp, int __excepts)
139 {
140 	fexcept_t __fpsr;
141 
142 	__get_fpsr(__fpsr);
143 
144 	__fpsr &= ~(__excepts & FE_ALL_EXCEPT);
145 	__fpsr |= *__flagp & __excepts & FE_ALL_EXCEPT;
146 
147 	__set_fpsr(__fpsr);
148 
149 	return 0;
150 }
151 
152 __fenv_static inline int
153 feraiseexcept(int __excepts)
154 {
155 	if (__excepts & FE_INVALID)	/* Inf * 0 */
156 		__fmul("%.s %#0r0,%0", double, __builtin_huge_val());
157 
158 	if (__excepts & FE_DIVBYZERO)	/* 1.0 / 0 */
159 		__fdiv("%.s %#0r0,%0", double, 1.0);
160 
161 	if (__excepts & FE_OVERFLOW)	/* MAX * MAX */
162 		__fmul("%.x %0,%0", long double, LDBL_MAX);
163 
164 	if (__excepts & FE_UNDERFLOW)	/* e ^ -MAX */
165 		__fetox("%.x %0", long double, -LDBL_MAX);
166 
167 	if (__excepts & FE_INEXACT)	/* 1 / 3 */
168 		__fdiv("%.s %#0r3,%0", long double, 1.0);
169 
170 	return 0;
171 }
172 
173 __fenv_static inline int
174 fetestexcept(int __excepts)
175 {
176 	fexcept_t __fpsr;
177 
178 	__get_fpsr(__fpsr);
179 
180 	return __fpsr & __excepts & FE_ALL_EXCEPT;
181 }
182 
183 __fenv_static inline int
184 fegetround(void)
185 {
186 	fexcept_t __fpcr;
187 
188 	__get_fpcr(__fpcr);
189 	return __fpcr & _ROUND_MASK;
190 }
191 
192 __fenv_static inline int
193 fesetround(int __round)
194 {
195 	fexcept_t __fpcr;
196 
197 	if (__round & ~_ROUND_MASK)
198 		return -1;
199 
200 	__get_fpcr(__fpcr);
201 
202 	__fpcr &= ~_ROUND_MASK;
203 	__fpcr |= __round;
204 
205 	__set_fpcr(__fpcr);
206 
207 	return 0;
208 }
209 
210 __fenv_static inline int
211 fegetenv(fenv_t *__envp)
212 {
213 	__fgetenv(*__envp);
214 
215 	return 0;
216 }
217 
218 __fenv_static inline int
219 feholdexcept(fenv_t *__envp)
220 {
221 	fexcept_t __fpcr, __fpsr;
222 
223 	__fgetenv(*__envp);
224 	__fpsr = __envp->fpsr & ~FE_ALL_EXCEPT;
225 	__set_fpsr(__fpsr);	/* clear all */
226 	__fpcr = __envp->fpcr & ~(FE_ALL_EXCEPT << 6);
227 	__set_fpcr(__fpcr);	/* set non/stop */
228 
229 	return 0;
230 }
231 
232 __fenv_static inline int
233 fesetenv(const fenv_t *__envp)
234 {
235 	fenv_t __tenv;
236 
237 	__fgetenv(__tenv);
238 
239 	if (__envp == FE_DFL_ENV) {
240 		__tenv.fpcr |=
241 		    __envp->fpcr & ((FE_ALL_EXCEPT << 6) | FE_UPWARD);
242 		__tenv.fpsr |= __envp->fpsr & FE_ALL_EXCEPT;
243 	}
244 
245 	__fsetenv(__tenv);
246 
247 	return 0;
248 }
249 
250 __fenv_static inline int
251 feupdateenv(const fenv_t *__envp)
252 {
253 	fexcept_t __fpsr;
254 
255 	__get_fpsr(__fpsr);
256 	__fpsr &= FE_ALL_EXCEPT;
257 	fesetenv(__envp);
258 	feraiseexcept((int)__fpsr);
259 	return 0;
260 }
261 
262 #if defined(_NETBSD_SOURCE) || defined(_GNU_SOURCE)
263 
264 __fenv_static inline int
265 feenableexcept(int __mask)
266 {
267 	fexcept_t __fpcr, __oldmask;
268 
269 	__get_fpcr(__fpcr);
270 	__oldmask = (__fpcr >> 6) & FE_ALL_EXCEPT;
271 	__fpcr |= (__mask & FE_ALL_EXCEPT) << 6;
272 	__set_fpcr(__fpcr);
273 
274 	return __oldmask;
275 }
276 
277 __fenv_static inline int
278 fedisableexcept(int __mask)
279 {
280 	fexcept_t __fpcr, __oldmask;
281 
282 	__get_fpcr(__fpcr);
283 	__oldmask = (__fpcr >> 6) & FE_ALL_EXCEPT;
284 	__fpcr &= ~((__mask & FE_ALL_EXCEPT) << 6);
285 	__set_fpcr(__fpcr);
286 
287 	return __oldmask;
288 }
289 
290 __fenv_static inline int
291 fegetexcept(void)
292 {
293 	fexcept_t __fpcr;
294 
295 	__get_fpcr(__fpcr);
296 
297 	return (__fpcr >> 6) & FE_ALL_EXCEPT;
298 }
299 
300 #endif /* _NETBSD_SOURCE || _GNU_SOURCE */
301 
302 __END_DECLS
303 
304 #endif /* __HAVE_68881__ */
305 
306 #endif /* _M68K_FENV_H_ */
307