1/*	$NetBSD: fenv.h,v 1.3 2017/03/22 23:11:10 chs 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/stdint.h>
36#include <sh3/float.h>
37#include <sh3/fpreg.h>
38
39#ifndef __fenv_static
40#define __fenv_static   static
41#endif
42
43/* Exception bits, from FPSCR */
44#define	FE_INEXACT	((uint32_t)FPSCR_EXCEPTION_INEXACT >> 5)
45#define	FE_DIVBYZERO	((uint32_t)FPSCR_EXCEPTION_ZERODIV >> 5)
46#define	FE_UNDERFLOW	((uint32_t)FPSCR_EXCEPTION_UNDERFLOW >> 5)
47#define	FE_OVERFLOW	((uint32_t)FPSCR_EXCEPTION_OVERFLOW >> 5)
48#define	FE_INVALID	((uint32_t)FPSCR_EXCEPTION_INVALID >> 5)
49
50#define FE_ALL_EXCEPT \
51    (FE_INEXACT | FE_DIVBYZERO | FE_UNDERFLOW | FE_OVERFLOW | FE_INVALID)
52
53/* Rounding modes, from FPSCR */
54#define FE_TONEAREST	FPSCR_ROUND_NEAREST
55#define	FE_TOWARDZERO	FPSCR_ROUND_ZERO
56/* These two don't exist and are only defined for the benefit of softfloat */
57#define	FE_DOWNWARD	(FPSCR_ROUND_ZERO + 1)
58#define	FE_UPWARD	(FPSCR_ROUND_ZERO + 2)
59
60#define _ROUND_MASK	\
61    (FE_TONEAREST | FE_TOWARDZERO)
62
63#ifdef __SH_FPU_ANY__
64
65typedef uint32_t fexcept_t;
66
67typedef struct {
68	uint32_t __fpscr;
69} fenv_t;
70
71#define FE_DFL_ENV      ((fenv_t *) -1)
72
73#define __get_fpscr(__fpscr) \
74    __asm__ __volatile__ ("sts fpscr,%0" : "=r" (__fpscr))
75#define __set_fpscr(__fpscr) \
76    __asm__ __volatile__ ("lds %0,fpscr" : : "r" (__fpscr))
77
78__BEGIN_DECLS
79
80__fenv_static inline int
81feclearexcept(int __excepts)
82{
83	fexcept_t __fpscr;
84
85	__excepts &= FE_ALL_EXCEPT;
86
87	__get_fpscr(__fpscr);
88	__fpscr &= ~__excepts;
89	__set_fpscr(__fpscr);
90
91	return 0;
92}
93
94__fenv_static inline int
95fegetexceptflag(fexcept_t *__flagp, int __excepts)
96{
97	fexcept_t __fpscr;
98
99	__get_fpscr(__fpscr);
100
101	*__flagp = __fpscr & __excepts & FE_ALL_EXCEPT;
102
103	return 0;
104}
105
106__fenv_static inline int
107fesetexceptflag(const fexcept_t *__flagp, int __excepts)
108{
109	fexcept_t __fpscr;
110
111	__get_fpscr(__fpscr);
112
113	__fpscr &= ~(__excepts & FE_ALL_EXCEPT);
114	__fpscr |= *__flagp & __excepts & FE_ALL_EXCEPT;
115
116	__set_fpscr(__fpscr);
117
118	return 0;
119}
120
121static inline void
122__fmul(double a, double b)
123{
124#ifdef __sh4__
125	__asm__ __volatile__ ("fmul %1, %0" : "+d" (a) : "d" (b));
126#endif
127}
128
129static inline void
130__fdiv(double a, double b) {
131#ifdef __sh4__
132	__asm__ __volatile__ ("fdiv %1, %0" : "+d" (a) : "d" (b));
133#endif
134}
135
136__fenv_static inline int
137feraiseexcept(int __excepts)
138{
139	fexcept_t __fpscr;
140
141	if (__excepts & FE_INVALID)	/* Inf * 0 */
142		__fmul(__builtin_huge_val(), 0.0);
143
144	if (__excepts & FE_DIVBYZERO)	/* 1.0 / 0 */
145		__fdiv(1.0, 0.0);
146
147	if (__excepts & FE_OVERFLOW)	/* MAX * MAX */
148		__fmul(LDBL_MAX, LDBL_MAX);
149
150	if (__excepts & FE_UNDERFLOW)	/* MIN / 10.0 */
151		__fdiv(LDBL_MIN, 10.0);
152
153	if (__excepts & FE_INEXACT)	/* 1 / 3 */
154		__fdiv(1.0, 3.0);
155
156	__get_fpscr(__fpscr);
157
158	__fpscr |= __excepts & FE_ALL_EXCEPT;
159
160	__set_fpscr(__fpscr);
161
162	return 0;
163}
164
165__fenv_static inline int
166fetestexcept(int __excepts)
167{
168	fexcept_t __fpscr;
169
170	__get_fpscr(__fpscr);
171
172	return __fpscr & __excepts & FE_ALL_EXCEPT;
173}
174
175__fenv_static inline int
176fegetround(void)
177{
178	fexcept_t __fpscr;
179
180	__get_fpscr(__fpscr);
181	return __fpscr & _ROUND_MASK;
182}
183
184__fenv_static inline int
185fesetround(int __round)
186{
187	fexcept_t __fpscr;
188
189	if (__round & ~_ROUND_MASK)
190		return -1;
191
192	__get_fpscr(__fpscr);
193
194	__fpscr &= ~_ROUND_MASK;
195	__fpscr |= __round;
196
197	__set_fpscr(__fpscr);
198
199	return 0;
200}
201
202__fenv_static inline int
203fegetenv(fenv_t *__envp)
204{
205	fexcept_t __fpscr;
206
207	__get_fpscr(__fpscr);
208	__envp->__fpscr = __fpscr;
209
210	return 0;
211}
212
213__fenv_static inline int
214feholdexcept(fenv_t *__envp)
215{
216	fexcept_t __fpscr;
217
218	__get_fpscr(__fpscr);
219	__envp->__fpscr = __fpscr;
220
221	__fpscr &= ~FE_ALL_EXCEPT;
222	__fpscr &= ~(FE_ALL_EXCEPT << 5);
223	__set_fpscr(__fpscr);	/* clear all */
224
225	return 0;
226}
227
228__fenv_static inline int
229fesetenv(const fenv_t *__envp)
230{
231	if (__envp == FE_DFL_ENV)
232		__set_fpscr(FPSCR_DEFAULT);
233	else
234		__set_fpscr(__envp->__fpscr);
235
236	return 0;
237}
238
239__fenv_static inline int
240feupdateenv(const fenv_t *__envp)
241{
242	fexcept_t __fpscr;
243
244	__get_fpscr(__fpscr);
245	__fpscr &= FE_ALL_EXCEPT;
246	fesetenv(__envp);
247	feraiseexcept((int)__fpscr);
248	return 0;
249}
250
251#if defined(_NETBSD_SOURCE) || defined(_GNU_SOURCE)
252
253/* We currently provide no external definitions of the functions below. */
254
255static inline int
256feenableexcept(int __mask)
257{
258	fexcept_t __fpscr, __oldmask;
259
260	__get_fpscr(__fpscr);
261	__oldmask = (__fpscr >> 5) & FE_ALL_EXCEPT;
262	__fpscr |= (__mask & FE_ALL_EXCEPT) << 5;
263	__set_fpscr(__fpscr);
264
265	return __oldmask;
266}
267
268static inline int
269fedisableexcept(int __mask)
270{
271	fexcept_t __fpscr, __oldmask;
272
273	__get_fpscr(__fpscr);
274	__oldmask = (__fpscr >> 5) & FE_ALL_EXCEPT;
275	__fpscr &= ~(__mask & FE_ALL_EXCEPT) << 5;
276	__set_fpscr(__fpscr);
277
278	return __oldmask;
279}
280
281static inline int
282fegetexcept(void)
283{
284	fexcept_t __fpscr;
285
286	__get_fpscr(__fpscr);
287
288	return (__fpscr >> 5) & FE_ALL_EXCEPT;
289}
290
291#endif /* _NETBSD_SOURCE || _GNU_SOURCE */
292
293__END_DECLS
294
295#endif /* __SH_FPU_ANY__ */
296
297#endif /* _SH3_FENV_H_ */
298