1 /*- 2 * Copyright (c) 2004-2011 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 #error "This file is meant to be included only by <fenv.h>." 31 #endif 32 33 /* 34 * This file implements the functionality of <fenv.h> on platforms that 35 * lack an FPU and use softfloat in libc for floating point. To use it, 36 * you must write an <fenv.h> that provides the following: 37 * 38 * - a typedef for fenv_t, which may be an integer or struct type 39 * - a typedef for fexcept_t (XXX This file assumes fexcept_t is a 40 * simple integer type containing the exception mask.) 41 * - definitions of FE_* constants for the five exceptions and four 42 * rounding modes in IEEE 754, as described in fenv(3) 43 * - a definition, and the corresponding external symbol, for FE_DFL_ENV 44 * - a macro __set_env(env, flags, mask, rnd), which sets the given fenv_t 45 * from the exception flags, mask, and rounding mode 46 * - macros __env_flags(env), __env_mask(env), and __env_round(env), which 47 * extract fields from an fenv_t 48 * - a definition of __fenv_static 49 * 50 * If the architecture supports an optional FPU, it's recommended that you 51 * define fenv_t and fexcept_t to match the hardware ABI. Otherwise, it 52 * doesn't matter how you define them. 53 */ 54 55 extern int __softfloat_float_exception_flags; 56 extern int __softfloat_float_exception_mask; 57 extern int __softfloat_float_rounding_mode; 58 void __softfloat_float_raise(int); 59 60 __fenv_static inline int 61 feclearexcept(int __excepts) 62 { 63 64 __softfloat_float_exception_flags &= ~__excepts; 65 return (0); 66 } 67 68 __fenv_static inline int 69 fegetexceptflag(fexcept_t *__flagp, int __excepts) 70 { 71 72 *__flagp = __softfloat_float_exception_flags & __excepts; 73 return (0); 74 } 75 76 __fenv_static inline int 77 fesetexceptflag(const fexcept_t *__flagp, int __excepts) 78 { 79 80 __softfloat_float_exception_flags &= ~__excepts; 81 __softfloat_float_exception_flags |= *__flagp & __excepts; 82 return (0); 83 } 84 85 __fenv_static inline int 86 feraiseexcept(int __excepts) 87 { 88 89 __softfloat_float_raise(__excepts); 90 return (0); 91 } 92 93 __fenv_static inline int 94 fetestexcept(int __excepts) 95 { 96 97 return (__softfloat_float_exception_flags & __excepts); 98 } 99 100 __fenv_static inline int 101 fegetround(void) 102 { 103 104 return (__softfloat_float_rounding_mode); 105 } 106 107 __fenv_static inline int 108 fesetround(int __round) 109 { 110 111 __softfloat_float_rounding_mode = __round; 112 return (0); 113 } 114 115 __fenv_static inline int 116 fegetenv(fenv_t *__envp) 117 { 118 119 __set_env(*__envp, __softfloat_float_exception_flags, 120 __softfloat_float_exception_mask, __softfloat_float_rounding_mode); 121 return (0); 122 } 123 124 __fenv_static inline int 125 feholdexcept(fenv_t *__envp) 126 { 127 fenv_t __env; 128 129 fegetenv(__envp); 130 __softfloat_float_exception_flags = 0; 131 __softfloat_float_exception_mask = 0; 132 return (0); 133 } 134 135 __fenv_static inline int 136 fesetenv(const fenv_t *__envp) 137 { 138 139 __softfloat_float_exception_flags = __env_flags(*__envp); 140 __softfloat_float_exception_mask = __env_mask(*__envp); 141 __softfloat_float_rounding_mode = __env_round(*__envp); 142 return (0); 143 } 144 145 __fenv_static inline int 146 feupdateenv(const fenv_t *__envp) 147 { 148 int __oflags = __softfloat_float_exception_flags; 149 150 fesetenv(__envp); 151 feraiseexcept(__oflags); 152 return (0); 153 } 154 155 #if __BSD_VISIBLE 156 157 /* We currently provide no external definitions of the functions below. */ 158 159 __fenv_static inline int 160 feenableexcept(int __mask) 161 { 162 int __omask = __softfloat_float_exception_mask; 163 164 __softfloat_float_exception_mask |= __mask; 165 return (__omask); 166 } 167 168 __fenv_static inline int 169 fedisableexcept(int __mask) 170 { 171 int __omask = __softfloat_float_exception_mask; 172 173 __softfloat_float_exception_mask &= ~__mask; 174 return (__omask); 175 } 176 177 __fenv_static inline int 178 fegetexcept(void) 179 { 180 181 return (__softfloat_float_exception_mask); 182 } 183 184 #endif /* __BSD_VISIBLE */ 185