fenv.h revision 1.2 1 /* $NetBSD: fenv.h,v 1.2 2015/12/25 16:19:38 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 #ifndef __fenv_static
40 #define __fenv_static static
41 #endif
42
43 /* Exception bits, from FPSR */
44 #define FE_INEXACT FPSR_AINEX
45 #define FE_DIVBYZERO FPSR_ADZ
46 #define FE_UNDERFLOW FPSR_AUNFL
47 #define FE_OVERFLOW FPSR_AOVFL
48 #define FE_INVALID FPSR_AIOP
49
50 #define FE_ALL_EXCEPT \
51 (FE_INEXACT | FE_DIVBYZERO | FE_UNDERFLOW | FE_OVERFLOW | FE_INVALID)
52
53 /* Rounding modes, from FPSR */
54 #define FE_TONEAREST FPCR_NEAR
55 #define FE_TOWARDZERO FPCR_ZERO
56 #define FE_DOWNWARD FPCR_MINF
57 #define FE_UPWARD FPCR_PINF
58
59 #define _ROUND_MASK \
60 (FE_TONEAREST | FE_TOWARDZERO | FE_DOWNWARD | FE_UPWARD)
61
62 typedef uint32_t fexcept_t;
63
64 /* same layout as fmovem */
65 typedef struct {
66 uint32_t fpcr;
67 uint32_t fpsr;
68 uint32_t fppc;
69 } fenv_t;
70
71 #define FE_DFL_ENV ((fenv_t *) -1)
72
73 #define __get_fpcr(__fpcr) \
74 __asm__ __volatile__ ("fmove%.l %!,%0" : "=dm" (__fpcr))
75 #define __set_fpcr(__fpcr) \
76 __asm__ __volatile__ ("fmove%.l %0,%!" : : "dm" (__fpcr))
77
78 #define __get_fpsr(__fpsr) \
79 __asm__ __volatile__ ("fmove%.l %/fpsr,%0" : "=dm" (__fpsr))
80 #define __set_fpsr(__fpsr) \
81 __asm__ __volatile__ ("fmove%.l %0,%/fpsr" : : "dm" (__fpsr))
82
83 #define __fmul(__s, __t, __d) \
84 do { \
85 __t d = __d; \
86 __asm__ __volatile__ ("fmul" __s "; fnop" : "=f" (d) : "0" (d)); \
87 } while (/*CONSTCOND*/0)
88
89 #define __fdiv(__s, __t, __d) \
90 do { \
91 __t d = __d; \
92 __asm__ __volatile__ ("fdiv" __s "; fnop" : "=f" (d) : "0" (d)); \
93 } while (/*CONSTCOND*/0)
94
95 #define __fetox(__s, __t, __d) \
96 do { \
97 __t d = __d; \
98 __asm__ __volatile__ ("fetox" __s "; fnop" : "=f" (d) : "0" (d)); \
99 } while (/*CONSTCOND*/0)
100
101 #define __fgetenv(__envp) \
102 __asm__ __volatile__ ("fmovem%.l %/fpcr/%/fpsr/%/fpiar,%0" : "=m" (__envp))
103
104 #define __fsetenv(__envp) \
105 __asm__ __volatile__ ("fmovem%.l %0,%/fpcr/%/fpsr/%/fpiar" : : "m" (__envp))
106
107 __BEGIN_DECLS
108
109 __fenv_static inline int
110 feclearexcept(int __excepts)
111 {
112 fexcept_t __fpsr;
113
114 __excepts &= FE_ALL_EXCEPT;
115
116 __get_fpsr(__fpsr);
117 __fpsr &= ~__excepts;
118 __set_fpsr(__fpsr);
119
120 return 0;
121 }
122
123 __fenv_static inline int
124 fegetexceptflag(fexcept_t *__flagp, int __excepts)
125 {
126 fexcept_t __fpsr;
127
128 __get_fpsr(__fpsr);
129
130 *__flagp = __fpsr & __excepts & FE_ALL_EXCEPT;
131
132 return 0;
133 }
134
135 __fenv_static inline int
136 fesetexceptflag(const fexcept_t *__flagp, int __excepts)
137 {
138 fexcept_t __fpsr;
139
140 __get_fpsr(__fpsr);
141
142 __fpsr &= ~(__excepts & FE_ALL_EXCEPT);
143 __fpsr |= *__flagp & __excepts & FE_ALL_EXCEPT;
144
145 __set_fpsr(__fpsr);
146
147 return 0;
148 }
149
150 __fenv_static inline int
151 feraiseexcept(int __excepts)
152 {
153 if (__excepts & FE_INVALID) /* Inf * 0 */
154 __fmul("%.s %#0r0,%0", double, __builtin_huge_val());
155
156 if (__excepts & FE_DIVBYZERO) /* 1.0 / 0 */
157 __fdiv("%.s %#0r0,%0", double, 1.0);
158
159 if (__excepts & FE_OVERFLOW) /* MAX * MAX */
160 __fmul("%.x %0,%0", long double, LDBL_MAX);
161
162 if (__excepts & FE_UNDERFLOW) /* e ^ -MAX */
163 __fetox("%.x %0", long double, -LDBL_MAX);
164
165 if (__excepts & FE_INEXACT) /* 1 / 3 */
166 __fdiv("%.s %#0r3,%0", long double, 1.0);
167
168 return 0;
169 }
170
171 __fenv_static inline int
172 fetestexcept(int __excepts)
173 {
174 fexcept_t __fpsr;
175
176 __get_fpsr(__fpsr);
177
178 return __fpsr & __excepts & FE_ALL_EXCEPT;
179 }
180
181 __fenv_static inline int
182 fegetround(void)
183 {
184 fexcept_t __fpcr;
185
186 __get_fpcr(__fpcr);
187 return __fpcr & _ROUND_MASK;
188 }
189
190 __fenv_static inline int
191 fesetround(int __round)
192 {
193 fexcept_t __fpcr;
194
195 if (__round & ~_ROUND_MASK)
196 return -1;
197
198 __get_fpcr(__fpcr);
199
200 __fpcr &= ~_ROUND_MASK;
201 __fpcr |= __round;
202
203 __set_fpcr(__fpcr);
204
205 return 0;
206 }
207
208 __fenv_static inline int
209 fegetenv(fenv_t *__envp)
210 {
211 __fgetenv(__envp);
212
213 return 0;
214 }
215
216 __fenv_static inline int
217 feholdexcept(fenv_t *__envp)
218 {
219 fexcept_t __fpcr, __fpsr;
220
221 __fgetenv(__envp);
222 __fpsr = __envp->fpsr & ~FE_ALL_EXCEPT;
223 __set_fpsr(__fpsr); /* clear all */
224 __fpcr = __envp->fpcr & ~(FE_ALL_EXCEPT << 6);
225 __set_fpcr(__fpcr); /* set non/stop */
226
227 return 0;
228 }
229
230 __fenv_static inline int
231 fesetenv(const fenv_t *__envp)
232 {
233 fenv_t __tenv;
234
235 __fgetenv(__tenv);
236
237 if (__envp == FE_DFL_ENV) {
238 __tenv.fpcr |=
239 __envp->fpcr & ((FE_ALL_EXCEPT << 6) | FE_UPWARD);
240 __tenv.fpsr |= __envp->fpsr & FE_ALL_EXCEPT;
241 }
242
243 __fsetenv(__tenv);
244
245 return 0;
246 }
247
248 __fenv_static inline int
249 feupdateenv(const fenv_t *__envp)
250 {
251 fexcept_t __fpsr;
252
253 __get_fpsr(__fpsr);
254 __fpsr &= FE_ALL_EXCEPT;
255 fesetenv(__envp);
256 feraiseexcept((int)__fpsr);
257 return 0;
258 }
259
260 #if defined(_NETBSD_SOURCE) || defined(_GNU_SOURCE)
261
262 /* We currently provide no external definitions of the functions below. */
263
264 static inline int
265 feenableexcept(int __mask)
266 {
267 fexcept_t __fpsr, __oldmask;
268
269 __get_fpsr(__fpsr);
270 __oldmask = __fpsr & FE_ALL_EXCEPT;
271 __fpsr |= __mask & FE_ALL_EXCEPT;
272 __set_fpsr(__fpsr);
273
274 return __oldmask;
275 }
276
277 static inline int
278 fedisableexcept(int __mask)
279 {
280 fexcept_t __fpsr, __oldmask;
281
282 __get_fpsr(__fpsr);
283 __oldmask = __fpsr & FE_ALL_EXCEPT;
284 __fpsr &= ~(__mask & FE_ALL_EXCEPT);
285 __set_fpsr(__fpsr);
286
287 return __oldmask;
288 }
289
290 static inline int
291 fegetexcept(void)
292 {
293 fexcept_t __fpsr;
294
295 __get_fpsr(__fpsr);
296
297 return __fpsr & FE_ALL_EXCEPT;
298 }
299
300 #endif /* _NETBSD_SOURCE || _GNU_SOURCE */
301
302 __END_DECLS
303
304 #endif /* _M68K_FENV_H_ */
305