1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2004-2005 David Schultz <[email protected]>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * $FreeBSD$
29 */
30
31 #ifndef _FENV_H_
32 #define _FENV_H_
33
34 #include <sys/_types.h>
35 #include <machine/endian.h>
36
37 #ifndef __fenv_static
38 #define __fenv_static static
39 #endif
40
41 typedef __uint32_t fenv_t;
42 typedef __uint32_t fexcept_t;
43
44 /* Exception flags */
45 #define FE_INEXACT 0x02000000
46 #define FE_DIVBYZERO 0x04000000
47 #define FE_UNDERFLOW 0x08000000
48 #define FE_OVERFLOW 0x10000000
49 #define FE_INVALID 0x20000000 /* all types of invalid FP ops */
50
51 /*
52 * The PowerPC architecture has extra invalid flags that indicate the
53 * specific type of invalid operation occurred. These flags may be
54 * tested, set, and cleared---but not masked---separately. All of
55 * these bits are cleared when FE_INVALID is cleared, but only
56 * FE_VXSOFT is set when FE_INVALID is explicitly set in software.
57 */
58 #define FE_VXCVI 0x00000100 /* invalid integer convert */
59 #define FE_VXSQRT 0x00000200 /* square root of a negative */
60 #define FE_VXSOFT 0x00000400 /* software-requested exception */
61 #define FE_VXVC 0x00080000 /* ordered comparison involving NaN */
62 #define FE_VXIMZ 0x00100000 /* inf * 0 */
63 #define FE_VXZDZ 0x00200000 /* 0 / 0 */
64 #define FE_VXIDI 0x00400000 /* inf / inf */
65 #define FE_VXISI 0x00800000 /* inf - inf */
66 #define FE_VXSNAN 0x01000000 /* operation on a signalling NaN */
67 #define FE_ALL_INVALID (FE_VXCVI | FE_VXSQRT | FE_VXSOFT | FE_VXVC | \
68 FE_VXIMZ | FE_VXZDZ | FE_VXIDI | FE_VXISI | \
69 FE_VXSNAN | FE_INVALID)
70 #define FE_ALL_EXCEPT (FE_DIVBYZERO | FE_INEXACT | \
71 FE_ALL_INVALID | FE_OVERFLOW | FE_UNDERFLOW)
72
73 /* Rounding modes */
74 #define FE_TONEAREST 0x0000
75 #define FE_TOWARDZERO 0x0001
76 #define FE_UPWARD 0x0002
77 #define FE_DOWNWARD 0x0003
78 #define _ROUND_MASK (FE_TONEAREST | FE_DOWNWARD | \
79 FE_UPWARD | FE_TOWARDZERO)
80
81 __BEGIN_DECLS
82
83 /* Default floating-point environment */
84 extern const fenv_t __fe_dfl_env;
85 #define FE_DFL_ENV (&__fe_dfl_env)
86
87 /* We need to be able to map status flag positions to mask flag positions */
88 #define _FPUSW_SHIFT 22
89 #define _ENABLE_MASK ((FE_DIVBYZERO | FE_INEXACT | FE_INVALID | \
90 FE_OVERFLOW | FE_UNDERFLOW) >> _FPUSW_SHIFT)
91
92 #ifndef _SOFT_FLOAT
93 #ifdef __SPE__
94 #define __mffs(__env) \
95 __asm __volatile("mfspr %0, 512" : "=r" ((__env)->__bits.__reg))
96 #define __mtfsf(__env) \
97 __asm __volatile("mtspr 512,%0;isync" :: "r" ((__env).__bits.__reg))
98 #else
99 #define __mffs(__env) \
100 __asm __volatile("mffs %0" : "=f" ((__env)->__d))
101 #define __mtfsf(__env) \
102 __asm __volatile("mtfsf 255,%0" :: "f" ((__env).__d))
103 #endif
104 #else
105 #define __mffs(__env)
106 #define __mtfsf(__env)
107 #endif
108
109 union __fpscr {
110 double __d;
111 struct {
112 #if _BYTE_ORDER == _LITTLE_ENDIAN
113 fenv_t __reg;
114 __uint32_t __junk;
115 #else
116 __uint32_t __junk;
117 fenv_t __reg;
118 #endif
119 } __bits;
120 };
121
122 __fenv_static inline int
feclearexcept(int __excepts)123 feclearexcept(int __excepts)
124 {
125 union __fpscr __r;
126
127 if (__excepts & FE_INVALID)
128 __excepts |= FE_ALL_INVALID;
129 __mffs(&__r);
130 __r.__bits.__reg &= ~__excepts;
131 __mtfsf(__r);
132 return (0);
133 }
134
135 __fenv_static inline int
fegetexceptflag(fexcept_t * __flagp,int __excepts)136 fegetexceptflag(fexcept_t *__flagp, int __excepts)
137 {
138 union __fpscr __r;
139
140 __mffs(&__r);
141 *__flagp = __r.__bits.__reg & __excepts;
142 return (0);
143 }
144
145 __fenv_static inline int
fesetexceptflag(const fexcept_t * __flagp,int __excepts)146 fesetexceptflag(const fexcept_t *__flagp, int __excepts)
147 {
148 union __fpscr __r;
149
150 if (__excepts & FE_INVALID)
151 __excepts |= FE_ALL_INVALID;
152 __mffs(&__r);
153 __r.__bits.__reg &= ~__excepts;
154 __r.__bits.__reg |= *__flagp & __excepts;
155 __mtfsf(__r);
156 return (0);
157 }
158
159 __fenv_static inline int
feraiseexcept(int __excepts)160 feraiseexcept(int __excepts)
161 {
162 union __fpscr __r;
163
164 if (__excepts & FE_INVALID)
165 __excepts |= FE_VXSOFT;
166 __mffs(&__r);
167 __r.__bits.__reg |= __excepts;
168 __mtfsf(__r);
169 return (0);
170 }
171
172 __fenv_static inline int
fetestexcept(int __excepts)173 fetestexcept(int __excepts)
174 {
175 union __fpscr __r;
176
177 __mffs(&__r);
178 return (__r.__bits.__reg & __excepts);
179 }
180
181 __fenv_static inline int
fegetround(void)182 fegetround(void)
183 {
184 union __fpscr __r;
185
186 __mffs(&__r);
187 return (__r.__bits.__reg & _ROUND_MASK);
188 }
189
190 __fenv_static inline int
fesetround(int __round)191 fesetround(int __round)
192 {
193 union __fpscr __r;
194
195 if (__round & ~_ROUND_MASK)
196 return (-1);
197 __mffs(&__r);
198 __r.__bits.__reg &= ~_ROUND_MASK;
199 __r.__bits.__reg |= __round;
200 __mtfsf(__r);
201 return (0);
202 }
203
204 __fenv_static inline int
fegetenv(fenv_t * __envp)205 fegetenv(fenv_t *__envp)
206 {
207 union __fpscr __r;
208
209 __mffs(&__r);
210 *__envp = __r.__bits.__reg;
211 return (0);
212 }
213
214 __fenv_static inline int
feholdexcept(fenv_t * __envp)215 feholdexcept(fenv_t *__envp)
216 {
217 union __fpscr __r;
218
219 __mffs(&__r);
220 *__envp = __r.__bits.__reg;
221 __r.__bits.__reg &= ~(FE_ALL_EXCEPT | _ENABLE_MASK);
222 __mtfsf(__r);
223 return (0);
224 }
225
226 __fenv_static inline int
fesetenv(const fenv_t * __envp)227 fesetenv(const fenv_t *__envp)
228 {
229 union __fpscr __r;
230
231 __r.__bits.__reg = *__envp;
232 __mtfsf(__r);
233 return (0);
234 }
235
236 __fenv_static inline int
feupdateenv(const fenv_t * __envp)237 feupdateenv(const fenv_t *__envp)
238 {
239 union __fpscr __r;
240
241 __mffs(&__r);
242 __r.__bits.__reg &= FE_ALL_EXCEPT;
243 __r.__bits.__reg |= *__envp;
244 __mtfsf(__r);
245 return (0);
246 }
247
248 #if __BSD_VISIBLE
249
250 /* We currently provide no external definitions of the functions below. */
251
252 static inline int
feenableexcept(int __mask)253 feenableexcept(int __mask)
254 {
255 union __fpscr __r;
256 fenv_t __oldmask;
257
258 __mffs(&__r);
259 __oldmask = __r.__bits.__reg;
260 __r.__bits.__reg |= (__mask & FE_ALL_EXCEPT) >> _FPUSW_SHIFT;
261 __mtfsf(__r);
262 return ((__oldmask & _ENABLE_MASK) << _FPUSW_SHIFT);
263 }
264
265 static inline int
fedisableexcept(int __mask)266 fedisableexcept(int __mask)
267 {
268 union __fpscr __r;
269 fenv_t __oldmask;
270
271 __mffs(&__r);
272 __oldmask = __r.__bits.__reg;
273 __r.__bits.__reg &= ~((__mask & FE_ALL_EXCEPT) >> _FPUSW_SHIFT);
274 __mtfsf(__r);
275 return ((__oldmask & _ENABLE_MASK) << _FPUSW_SHIFT);
276 }
277
278 static inline int
fegetexcept(void)279 fegetexcept(void)
280 {
281 union __fpscr __r;
282
283 __mffs(&__r);
284 return ((__r.__bits.__reg & _ENABLE_MASK) << _FPUSW_SHIFT);
285 }
286
287 #endif /* __BSD_VISIBLE */
288
289 __END_DECLS
290
291 #endif /* !_FENV_H_ */
292