xref: /netbsd-src/sys/arch/sh3/include/fenv.h (revision cddc78ea67e20759c213d3f50ea3bd06ade17338)
1 /*	$NetBSD: fenv.h,v 1.4 2024/10/30 15:56:12 riastradh Exp $	*/
2 
3 /*-
4  * Copyright (c) 2016 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 _SH3_FENV_H_
33 #define _SH3_FENV_H_
34 
35 #include <sys/featuretest.h>
36 #include <sys/stdint.h>
37 
38 #include <sh3/float.h>
39 #include <sh3/fpreg.h>
40 
41 #ifndef __fenv_static
42 #define __fenv_static   static
43 #endif
44 
45 /* Exception bits, from FPSCR */
46 #define	FE_INEXACT	((uint32_t)FPSCR_EXCEPTION_INEXACT >> 5)
47 #define	FE_DIVBYZERO	((uint32_t)FPSCR_EXCEPTION_ZERODIV >> 5)
48 #define	FE_UNDERFLOW	((uint32_t)FPSCR_EXCEPTION_UNDERFLOW >> 5)
49 #define	FE_OVERFLOW	((uint32_t)FPSCR_EXCEPTION_OVERFLOW >> 5)
50 #define	FE_INVALID	((uint32_t)FPSCR_EXCEPTION_INVALID >> 5)
51 
52 #define FE_ALL_EXCEPT \
53     (FE_INEXACT | FE_DIVBYZERO | FE_UNDERFLOW | FE_OVERFLOW | FE_INVALID)
54 
55 /* Rounding modes, from FPSCR */
56 #define FE_TONEAREST	FPSCR_ROUND_NEAREST
57 #define	FE_TOWARDZERO	FPSCR_ROUND_ZERO
58 /* These two don't exist and are only defined for the benefit of softfloat */
59 #define	FE_DOWNWARD	(FPSCR_ROUND_ZERO + 1)
60 #define	FE_UPWARD	(FPSCR_ROUND_ZERO + 2)
61 
62 #define _ROUND_MASK	\
63     (FE_TONEAREST | FE_TOWARDZERO)
64 
65 #ifdef __SH_FPU_ANY__
66 
67 typedef uint32_t fexcept_t;
68 
69 typedef struct {
70 	uint32_t __fpscr;
71 } fenv_t;
72 
73 #define FE_DFL_ENV      ((fenv_t *) -1)
74 
75 #define __get_fpscr(__fpscr) \
76     __asm__ __volatile__ ("sts fpscr,%0" : "=r" (__fpscr))
77 #define __set_fpscr(__fpscr) \
78     __asm__ __volatile__ ("lds %0,fpscr" : : "r" (__fpscr))
79 
80 __BEGIN_DECLS
81 
82 __fenv_static inline int
83 feclearexcept(int __excepts)
84 {
85 	fexcept_t __fpscr;
86 
87 	__excepts &= FE_ALL_EXCEPT;
88 
89 	__get_fpscr(__fpscr);
90 	__fpscr &= ~__excepts;
91 	__set_fpscr(__fpscr);
92 
93 	return 0;
94 }
95 
96 __fenv_static inline int
97 fegetexceptflag(fexcept_t *__flagp, int __excepts)
98 {
99 	fexcept_t __fpscr;
100 
101 	__get_fpscr(__fpscr);
102 
103 	*__flagp = __fpscr & __excepts & FE_ALL_EXCEPT;
104 
105 	return 0;
106 }
107 
108 __fenv_static inline int
109 fesetexceptflag(const fexcept_t *__flagp, int __excepts)
110 {
111 	fexcept_t __fpscr;
112 
113 	__get_fpscr(__fpscr);
114 
115 	__fpscr &= ~(__excepts & FE_ALL_EXCEPT);
116 	__fpscr |= *__flagp & __excepts & FE_ALL_EXCEPT;
117 
118 	__set_fpscr(__fpscr);
119 
120 	return 0;
121 }
122 
123 static inline void
124 __fmul(double a, double b)
125 {
126 #ifdef __sh4__
127 	__asm__ __volatile__ ("fmul %1, %0" : "+d" (a) : "d" (b));
128 #endif
129 }
130 
131 static inline void
132 __fdiv(double a, double b) {
133 #ifdef __sh4__
134 	__asm__ __volatile__ ("fdiv %1, %0" : "+d" (a) : "d" (b));
135 #endif
136 }
137 
138 __fenv_static inline int
139 feraiseexcept(int __excepts)
140 {
141 	fexcept_t __fpscr;
142 
143 	if (__excepts & FE_INVALID)	/* Inf * 0 */
144 		__fmul(__builtin_huge_val(), 0.0);
145 
146 	if (__excepts & FE_DIVBYZERO)	/* 1.0 / 0 */
147 		__fdiv(1.0, 0.0);
148 
149 	if (__excepts & FE_OVERFLOW)	/* MAX * MAX */
150 		__fmul(LDBL_MAX, LDBL_MAX);
151 
152 	if (__excepts & FE_UNDERFLOW)	/* MIN / 10.0 */
153 		__fdiv(LDBL_MIN, 10.0);
154 
155 	if (__excepts & FE_INEXACT)	/* 1 / 3 */
156 		__fdiv(1.0, 3.0);
157 
158 	__get_fpscr(__fpscr);
159 
160 	__fpscr |= __excepts & FE_ALL_EXCEPT;
161 
162 	__set_fpscr(__fpscr);
163 
164 	return 0;
165 }
166 
167 __fenv_static inline int
168 fetestexcept(int __excepts)
169 {
170 	fexcept_t __fpscr;
171 
172 	__get_fpscr(__fpscr);
173 
174 	return __fpscr & __excepts & FE_ALL_EXCEPT;
175 }
176 
177 __fenv_static inline int
178 fegetround(void)
179 {
180 	fexcept_t __fpscr;
181 
182 	__get_fpscr(__fpscr);
183 	return __fpscr & _ROUND_MASK;
184 }
185 
186 __fenv_static inline int
187 fesetround(int __round)
188 {
189 	fexcept_t __fpscr;
190 
191 	if (__round & ~_ROUND_MASK)
192 		return -1;
193 
194 	__get_fpscr(__fpscr);
195 
196 	__fpscr &= ~_ROUND_MASK;
197 	__fpscr |= __round;
198 
199 	__set_fpscr(__fpscr);
200 
201 	return 0;
202 }
203 
204 __fenv_static inline int
205 fegetenv(fenv_t *__envp)
206 {
207 	fexcept_t __fpscr;
208 
209 	__get_fpscr(__fpscr);
210 	__envp->__fpscr = __fpscr;
211 
212 	return 0;
213 }
214 
215 __fenv_static inline int
216 feholdexcept(fenv_t *__envp)
217 {
218 	fexcept_t __fpscr;
219 
220 	__get_fpscr(__fpscr);
221 	__envp->__fpscr = __fpscr;
222 
223 	__fpscr &= ~FE_ALL_EXCEPT;
224 	__fpscr &= ~(FE_ALL_EXCEPT << 5);
225 	__set_fpscr(__fpscr);	/* clear all */
226 
227 	return 0;
228 }
229 
230 __fenv_static inline int
231 fesetenv(const fenv_t *__envp)
232 {
233 	if (__envp == FE_DFL_ENV)
234 		__set_fpscr(FPSCR_DEFAULT);
235 	else
236 		__set_fpscr(__envp->__fpscr);
237 
238 	return 0;
239 }
240 
241 __fenv_static inline int
242 feupdateenv(const fenv_t *__envp)
243 {
244 	fexcept_t __fpscr;
245 
246 	__get_fpscr(__fpscr);
247 	__fpscr &= FE_ALL_EXCEPT;
248 	fesetenv(__envp);
249 	feraiseexcept((int)__fpscr);
250 	return 0;
251 }
252 
253 #if defined(_NETBSD_SOURCE) || defined(_GNU_SOURCE)
254 
255 /* We currently provide no external definitions of the functions below. */
256 
257 static inline int
258 feenableexcept(int __mask)
259 {
260 	fexcept_t __fpscr, __oldmask;
261 
262 	__get_fpscr(__fpscr);
263 	__oldmask = (__fpscr >> 5) & FE_ALL_EXCEPT;
264 	__fpscr |= (__mask & FE_ALL_EXCEPT) << 5;
265 	__set_fpscr(__fpscr);
266 
267 	return __oldmask;
268 }
269 
270 static inline int
271 fedisableexcept(int __mask)
272 {
273 	fexcept_t __fpscr, __oldmask;
274 
275 	__get_fpscr(__fpscr);
276 	__oldmask = (__fpscr >> 5) & FE_ALL_EXCEPT;
277 	__fpscr &= ~(__mask & FE_ALL_EXCEPT) << 5;
278 	__set_fpscr(__fpscr);
279 
280 	return __oldmask;
281 }
282 
283 static inline int
284 fegetexcept(void)
285 {
286 	fexcept_t __fpscr;
287 
288 	__get_fpscr(__fpscr);
289 
290 	return (__fpscr >> 5) & FE_ALL_EXCEPT;
291 }
292 
293 #endif /* _NETBSD_SOURCE || _GNU_SOURCE */
294 
295 __END_DECLS
296 
297 #endif /* __SH_FPU_ANY__ */
298 
299 #endif /* _SH3_FENV_H_ */
300