fenv.h revision 1.5 
1/*	$NetBSD: fenv.h,v 1.5 2017/02/27 06:47:30 chs 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 FPCR */
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#if !defined(__mc68010__) && !defined(__mcoldfire__)
63
64typedef uint32_t fexcept_t;
65
66/* same layout as fmovem */
67typedef 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
112feclearexcept(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
126fegetexceptflag(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
138fesetexceptflag(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
153feraiseexcept(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
174fetestexcept(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
184fegetround(void)
185{
186	fexcept_t __fpcr;
187
188	__get_fpcr(__fpcr);
189	return __fpcr & _ROUND_MASK;
190}
191
192__fenv_static inline int
193fesetround(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
211fegetenv(fenv_t *__envp)
212{
213	__fgetenv(__envp);
214
215	return 0;
216}
217
218__fenv_static inline int
219feholdexcept(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
233fesetenv(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
251feupdateenv(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/* We currently provide no external definitions of the functions below. */
265
266static inline int
267feenableexcept(int __mask)
268{
269	fexcept_t __fpcr, __oldmask;
270
271	__get_fpcr(__fpcr);
272	__oldmask = (__fpcr >> 6) & FE_ALL_EXCEPT;
273	__fpcr |= (__mask & FE_ALL_EXCEPT) << 6;
274	__set_fpcr(__fpcr);
275
276	return __oldmask;
277}
278
279static inline int
280fedisableexcept(int __mask)
281{
282	fexcept_t __fpcr, __oldmask;
283
284	__get_fpcr(__fpcr);
285	__oldmask = (__fpcr >> 6) & FE_ALL_EXCEPT;
286	__fpcr &= ~((__mask & FE_ALL_EXCEPT) << 6);
287	__set_fpcr(__fpcr);
288
289	return __oldmask;
290}
291
292static inline int
293fegetexcept(void)
294{
295	fexcept_t __fpcr;
296
297	__get_fpcr(__fpcr);
298
299	return (__fpcr >> 6) & FE_ALL_EXCEPT;
300}
301
302#endif /* _NETBSD_SOURCE || _GNU_SOURCE */
303
304__END_DECLS
305
306#endif /* !__m68010__ && !__mcoldfire__ */
307
308#endif /* _M68K_FENV_H_ */
309