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