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 #ifndef __fenv_static 35 #define __fenv_static static 36 #endif 37 38 /* The high 32 bits contain fpcr, low 32 contain fpsr. */ 39 typedef __uint64_t fenv_t; 40 typedef __uint64_t fexcept_t; 41 42 /* Exception flags */ 43 #define FE_INVALID 0x00000001 44 #define FE_DIVBYZERO 0x00000002 45 #define FE_OVERFLOW 0x00000004 46 #define FE_UNDERFLOW 0x00000008 47 #define FE_INEXACT 0x00000010 48 #define FE_ALL_EXCEPT (FE_DIVBYZERO | FE_INEXACT | \ 49 FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW) 50 51 /* 52 * Rounding modes 53 * 54 * We can't just use the hardware bit values here, because that would 55 * make FE_UPWARD and FE_DOWNWARD negative, which is not allowed. 56 */ 57 #define FE_TONEAREST 0x0 58 #define FE_UPWARD 0x1 59 #define FE_DOWNWARD 0x2 60 #define FE_TOWARDZERO 0x3 61 #define _ROUND_MASK (FE_TONEAREST | FE_DOWNWARD | \ 62 FE_UPWARD | FE_TOWARDZERO) 63 #define _ROUND_SHIFT 22 64 65 __BEGIN_DECLS 66 67 /* Default floating-point environment */ 68 extern const fenv_t __fe_dfl_env; 69 #define FE_DFL_ENV (&__fe_dfl_env) 70 71 /* We need to be able to map status flag positions to mask flag positions */ 72 #define _FPUSW_SHIFT 8 73 #define _ENABLE_MASK (FE_ALL_EXCEPT << _FPUSW_SHIFT) 74 75 #define __mrs_fpcr(__r) __asm __volatile("mrs %0, fpcr" : "=r" (__r)) 76 #define __msr_fpcr(__r) __asm __volatile("msr fpcr, %0" : : "r" (__r)) 77 78 #define __mrs_fpsr(__r) __asm __volatile("mrs %0, fpsr" : "=r" (__r)) 79 #define __msr_fpsr(__r) __asm __volatile("msr fpsr, %0" : : "r" (__r)) 80 81 __fenv_static __inline int 82 feclearexcept(int __excepts) 83 { 84 fexcept_t __r; 85 86 __mrs_fpsr(__r); 87 __r &= ~__excepts; 88 __msr_fpsr(__r); 89 return (0); 90 } 91 92 __fenv_static inline int 93 fegetexceptflag(fexcept_t *__flagp, int __excepts) 94 { 95 fexcept_t __r; 96 97 __mrs_fpsr(__r); 98 *__flagp = __r & __excepts; 99 return (0); 100 } 101 102 __fenv_static inline int 103 fesetexceptflag(const fexcept_t *__flagp, int __excepts) 104 { 105 fexcept_t __r; 106 107 __mrs_fpsr(__r); 108 __r &= ~__excepts; 109 __r |= *__flagp & __excepts; 110 __msr_fpsr(__r); 111 return (0); 112 } 113 114 __fenv_static inline int 115 feraiseexcept(int __excepts) 116 { 117 fexcept_t __r; 118 119 __mrs_fpsr(__r); 120 __r |= __excepts; 121 __msr_fpsr(__r); 122 return (0); 123 } 124 125 __fenv_static inline int 126 fetestexcept(int __excepts) 127 { 128 fexcept_t __r; 129 130 __mrs_fpsr(__r); 131 return (__r & __excepts); 132 } 133 134 __fenv_static inline int 135 fegetround(void) 136 { 137 fenv_t __r; 138 139 __mrs_fpcr(__r); 140 return ((__r >> _ROUND_SHIFT) & _ROUND_MASK); 141 } 142 143 __fenv_static inline int 144 fesetround(int __round) 145 { 146 fenv_t __r; 147 148 if (__round & ~_ROUND_MASK) 149 return (-1); 150 __mrs_fpcr(__r); 151 __r &= ~(_ROUND_MASK << _ROUND_SHIFT); 152 __r |= __round << _ROUND_SHIFT; 153 __msr_fpcr(__r); 154 return (0); 155 } 156 157 __fenv_static inline int 158 fegetenv(fenv_t *__envp) 159 { 160 __uint64_t fpcr; 161 __uint64_t fpsr; 162 163 __mrs_fpcr(fpcr); 164 __mrs_fpsr(fpsr); 165 *__envp = fpsr | (fpcr << 32); 166 167 return (0); 168 } 169 170 __fenv_static inline int 171 feholdexcept(fenv_t *__envp) 172 { 173 fenv_t __r; 174 175 __mrs_fpcr(__r); 176 *__envp = __r << 32; 177 __r &= ~(_ENABLE_MASK); 178 __msr_fpcr(__r); 179 180 __mrs_fpsr(__r); 181 *__envp |= (__uint32_t)__r; 182 __r &= ~(_ENABLE_MASK); 183 __msr_fpsr(__r); 184 return (0); 185 } 186 187 __fenv_static inline int 188 fesetenv(const fenv_t *__envp) 189 { 190 191 __msr_fpcr((*__envp) >> 32); 192 __msr_fpsr((fenv_t)(__uint32_t)*__envp); 193 return (0); 194 } 195 196 __fenv_static inline int 197 feupdateenv(const fenv_t *__envp) 198 { 199 fexcept_t __r; 200 201 __mrs_fpsr(__r); 202 fesetenv(__envp); 203 feraiseexcept(__r & FE_ALL_EXCEPT); 204 return (0); 205 } 206 207 #if __BSD_VISIBLE 208 209 /* We currently provide no external definitions of the functions below. */ 210 211 static inline int 212 feenableexcept(int __mask) 213 { 214 fenv_t __old_r, __new_r; 215 216 __mrs_fpcr(__old_r); 217 __new_r = __old_r | ((__mask & FE_ALL_EXCEPT) << _FPUSW_SHIFT); 218 __msr_fpcr(__new_r); 219 return ((__old_r >> _FPUSW_SHIFT) & FE_ALL_EXCEPT); 220 } 221 222 static inline int 223 fedisableexcept(int __mask) 224 { 225 fenv_t __old_r, __new_r; 226 227 __mrs_fpcr(__old_r); 228 __new_r = __old_r & ~((__mask & FE_ALL_EXCEPT) << _FPUSW_SHIFT); 229 __msr_fpcr(__new_r); 230 return ((__old_r >> _FPUSW_SHIFT) & FE_ALL_EXCEPT); 231 } 232 233 static inline int 234 fegetexcept(void) 235 { 236 fenv_t __r; 237 238 __mrs_fpcr(__r); 239 return ((__r & _ENABLE_MASK) >> _FPUSW_SHIFT); 240 } 241 242 #endif /* __BSD_VISIBLE */ 243 244 __END_DECLS 245 246 #endif /* !_FENV_H_ */ 247