fenv.h revision 1.3
1 /* $NetBSD: fenv.h,v 1.3 2019/10/27 21:27:10 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 2004-2005 David Schultz <das (at) FreeBSD.ORG> 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: src/lib/msun/alpha/fenv.h,v 1.3 2005/03/16 19:03:44 das Exp $ 29 */ 30 31 #ifndef _ALPHA_FENV_H_ 32 #define _ALPHA_FENV_H_ 33 34 #include <sys/stdint.h> 35 36 typedef __uint64_t fenv_t; 37 typedef __uint16_t fexcept_t; 38 39 /* Exception flags */ 40 #define FE_INVALID 0x01 41 #define FE_DIVBYZERO 0x02 42 #define FE_OVERFLOW 0x04 43 #define FE_UNDERFLOW 0x08 44 #define FE_INEXACT 0x10 45 #define FE_INTOVF 0x20 /* not maskable */ 46 #define FE_ALL_EXCEPT (FE_DIVBYZERO | FE_INEXACT | FE_INTOVF | \ 47 FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW) 48 49 /* Rounding modes */ 50 #define FE_TOWARDZERO 0x00 51 #define FE_DOWNWARD 0x01 52 #define FE_TONEAREST 0x02 53 #define FE_UPWARD 0x03 54 #define _ROUND_MASK (FE_TONEAREST | FE_DOWNWARD | \ 55 FE_UPWARD | FE_TOWARDZERO) 56 #define _ROUND_SHIFT 58 57 58 #define _FPUSW_SHIFT 52 59 60 #define __excb() __asm __volatile("excb") 61 #define __mf_fpcr(__cw) __asm __volatile("mf_fpcr %0" : "=f" (*(__cw))) 62 #define __mt_fpcr(__cw) __asm __volatile("mt_fpcr %0" : : "f" (__cw)) 63 64 union __fpcr { 65 double __d; 66 fenv_t __bits; 67 }; 68 69 __BEGIN_DECLS 70 71 /* Default floating-point environment */ 72 extern const fenv_t __fe_dfl_env; 73 #define FE_DFL_ENV (&__fe_dfl_env) 74 75 #if __GNUC_PREREQ__(8, 0) 76 #pragma GCC diagnostic push 77 #pragma GCC diagnostic ignored "-Wshadow" 78 #endif 79 80 static __inline int 81 feclearexcept(int __excepts) 82 { 83 union __fpcr __r; 84 85 __excb(); 86 __mf_fpcr(&__r.__d); 87 __r.__bits &= ~((fenv_t)__excepts << _FPUSW_SHIFT); 88 __mt_fpcr(__r.__d); 89 __excb(); 90 return 0; 91 } 92 93 static __inline int 94 fegetexceptflag(fexcept_t *__flagp, int __excepts) 95 { 96 union __fpcr __r; 97 98 __excb(); 99 __mf_fpcr(&__r.__d); 100 __excb(); 101 *__flagp = (__r.__bits >> _FPUSW_SHIFT) & __excepts; 102 return 0; 103 } 104 105 static __inline int 106 fesetexceptflag(const fexcept_t *__flagp, int __excepts) 107 { 108 union __fpcr __r; 109 fenv_t __xflag, __xexcepts; 110 111 __xflag = (fenv_t)*__flagp << _FPUSW_SHIFT; 112 __xexcepts = (fenv_t)__excepts << _FPUSW_SHIFT; 113 __excb(); 114 __mf_fpcr(&__r.__d); 115 __r.__bits &= ~__xexcepts; 116 __r.__bits |= __xflag & __xexcepts; 117 __mt_fpcr(__r.__d); 118 __excb(); 119 return 0; 120 } 121 122 static __inline int 123 feraiseexcept(int __excepts) 124 { 125 126 /* 127 * XXX Generating exceptions this way does not actually invoke 128 * a userland trap handler when enabled, but neither do 129 * arithmetic operations as far as I can tell. Perhaps there 130 * are more bugs in the kernel trap handler. 131 */ 132 fexcept_t __ex = __excepts; 133 fesetexceptflag(&__ex, __excepts); 134 return 0; 135 } 136 137 static __inline int 138 fetestexcept(int __excepts) 139 { 140 union __fpcr __r; 141 142 __excb(); 143 __mf_fpcr(&__r.__d); 144 __excb(); 145 return (__r.__bits >> _FPUSW_SHIFT) & __excepts; 146 } 147 148 static __inline int 149 fegetround(void) 150 { 151 union __fpcr __r; 152 153 /* 154 * No exception barriers should be required here if we assume 155 * that only fesetround() can change the rounding mode. 156 */ 157 __mf_fpcr(&__r.__d); 158 return (int)(__r.__bits >> _ROUND_SHIFT) & _ROUND_MASK; 159 } 160 161 static __inline int 162 fesetround(int __round) 163 { 164 union __fpcr __r; 165 166 if (__round & ~_ROUND_MASK) 167 return (-1); 168 __excb(); 169 __mf_fpcr(&__r.__d); 170 __r.__bits &= ~((fenv_t)_ROUND_MASK << _ROUND_SHIFT); 171 __r.__bits |= (fenv_t)__round << _ROUND_SHIFT; 172 __mt_fpcr(__r.__d); 173 __excb(); 174 return 0; 175 } 176 177 #if __GNUC_PREREQ__(8, 0) 178 #pragma GCC diagnostic pop 179 #endif 180 181 int fegetenv(fenv_t *); 182 int feholdexcept(fenv_t *); 183 int fesetenv(const fenv_t *); 184 int feupdateenv(const fenv_t *); 185 186 #if defined(_NETBSD_SOURCE) || defined(_GNU_SOURCE) 187 int feenableexcept(int); 188 int fedisableexcept(int); 189 int fegetexcept(void); 190 #endif /* _NETBSD_SOURCE || _GNU_SOURCE */ 191 192 193 __END_DECLS 194 195 #endif /* !_ALPHA_FENV_H_ */ 196
Indexes created Mon Sep 29 21:09:56 GMT 2025