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 typedef __uint32_t fenv_t; 39 typedef __uint32_t fexcept_t; 40 41 /* Exception flags */ 42 #define FE_INVALID 0x0001 43 #define FE_DIVBYZERO 0x0002 44 #define FE_OVERFLOW 0x0004 45 #define FE_UNDERFLOW 0x0008 46 #define FE_INEXACT 0x0010 47 #define FE_ALL_EXCEPT (FE_DIVBYZERO | FE_INEXACT | \ 48 FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW) 49 50 /* Rounding modes */ 51 #define FE_TONEAREST 0x0000 52 #define FE_TOWARDZERO 0x0001 53 #define FE_UPWARD 0x0002 54 #define FE_DOWNWARD 0x0003 55 #define _ROUND_MASK (FE_TONEAREST | FE_DOWNWARD | \ 56 FE_UPWARD | FE_TOWARDZERO) 57 __BEGIN_DECLS 58 59 /* Default floating-point environment */ 60 extern const fenv_t __fe_dfl_env; 61 #define FE_DFL_ENV (&__fe_dfl_env) 62 63 /* We need to be able to map status flag positions to mask flag positions */ 64 #define _FPUSW_SHIFT 16 65 #define _ENABLE_MASK (FE_ALL_EXCEPT << _FPUSW_SHIFT) 66 67 #ifdef ARM_HARD_FLOAT 68 #define __rfs(__fpsr) __asm __volatile("rfs %0" : "=r" (*(__fpsr))) 69 #define __wfs(__fpsr) __asm __volatile("wfs %0" : : "r" (__fpsr)) 70 #else 71 #define __rfs(__fpsr) 72 #define __wfs(__fpsr) 73 #endif 74 75 __fenv_static inline int 76 feclearexcept(int __excepts) 77 { 78 fexcept_t __fpsr; 79 80 __rfs(&__fpsr); 81 __fpsr &= ~__excepts; 82 __wfs(__fpsr); 83 return (0); 84 } 85 86 __fenv_static inline int 87 fegetexceptflag(fexcept_t *__flagp, int __excepts) 88 { 89 fexcept_t __fpsr; 90 91 __rfs(&__fpsr); 92 *__flagp = __fpsr & __excepts; 93 return (0); 94 } 95 96 __fenv_static inline int 97 fesetexceptflag(const fexcept_t *__flagp, int __excepts) 98 { 99 fexcept_t __fpsr; 100 101 __rfs(&__fpsr); 102 __fpsr &= ~__excepts; 103 __fpsr |= *__flagp & __excepts; 104 __wfs(__fpsr); 105 return (0); 106 } 107 108 __fenv_static inline int 109 feraiseexcept(int __excepts) 110 { 111 fexcept_t __ex = __excepts; 112 113 fesetexceptflag(&__ex, __excepts); /* XXX */ 114 return (0); 115 } 116 117 __fenv_static inline int 118 fetestexcept(int __excepts) 119 { 120 fexcept_t __fpsr; 121 122 __rfs(&__fpsr); 123 return (__fpsr & __excepts); 124 } 125 126 __fenv_static inline int 127 fegetround(void) 128 { 129 130 /* 131 * Apparently, the rounding mode is specified as part of the 132 * instruction format on ARM, so the dynamic rounding mode is 133 * indeterminate. Some FPUs may differ. 134 */ 135 return (-1); 136 } 137 138 __fenv_static inline int 139 fesetround(int __round) 140 { 141 142 return (-1); 143 } 144 145 __fenv_static inline int 146 fegetenv(fenv_t *__envp) 147 { 148 149 __rfs(__envp); 150 return (0); 151 } 152 153 __fenv_static inline int 154 feholdexcept(fenv_t *__envp) 155 { 156 fenv_t __env; 157 158 __rfs(&__env); 159 *__envp = __env; 160 __env &= ~(FE_ALL_EXCEPT | _ENABLE_MASK); 161 __wfs(__env); 162 return (0); 163 } 164 165 __fenv_static inline int 166 fesetenv(const fenv_t *__envp) 167 { 168 169 __wfs(*__envp); 170 return (0); 171 } 172 173 __fenv_static inline int 174 feupdateenv(const fenv_t *__envp) 175 { 176 fexcept_t __fpsr; 177 178 __rfs(&__fpsr); 179 __wfs(*__envp); 180 feraiseexcept(__fpsr & FE_ALL_EXCEPT); 181 return (0); 182 } 183 184 #if __BSD_VISIBLE 185 186 /* We currently provide no external definitions of the functions below. */ 187 188 static inline int 189 feenableexcept(int __mask) 190 { 191 fenv_t __old_fpsr, __new_fpsr; 192 193 __rfs(&__old_fpsr); 194 __new_fpsr = __old_fpsr | (__mask & FE_ALL_EXCEPT) << _FPUSW_SHIFT; 195 __wfs(__new_fpsr); 196 return ((__old_fpsr >> _FPUSW_SHIFT) & FE_ALL_EXCEPT); 197 } 198 199 static inline int 200 fedisableexcept(int __mask) 201 { 202 fenv_t __old_fpsr, __new_fpsr; 203 204 __rfs(&__old_fpsr); 205 __new_fpsr = __old_fpsr & ~((__mask & FE_ALL_EXCEPT) << _FPUSW_SHIFT); 206 __wfs(__new_fpsr); 207 return ((__old_fpsr >> _FPUSW_SHIFT) & FE_ALL_EXCEPT); 208 } 209 210 static inline int 211 fegetexcept(void) 212 { 213 fenv_t __fpsr; 214 215 __rfs(&__fpsr); 216 return ((__fpsr & _ENABLE_MASK) >> _FPUSW_SHIFT); 217 } 218 219 #endif /* __BSD_VISIBLE */ 220 221 __END_DECLS 222 223 #endif /* !_FENV_H_ */ 224