1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2004-2005 David Schultz <das@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 29 #include <sys/cdefs.h> 30 #include <sys/types.h> 31 #include <machine/fpu.h> 32 33 #define __fenv_static 34 #include "fenv.h" 35 36 #ifdef __GNUC_GNU_INLINE__ 37 #error "This file must be compiled with C99 'inline' semantics" 38 #endif 39 40 const fenv_t __fe_dfl_env = { 41 { 0xffff0000 | __INITIAL_FPUCW__, 42 0xffff0000, 43 0xffffffff, 44 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 45 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff } 46 }, 47 __INITIAL_MXCSR__ 48 }; 49 50 extern inline int feclearexcept(int __excepts); 51 extern inline int fegetexceptflag(fexcept_t *__flagp, int __excepts); 52 53 int 54 fesetexceptflag(const fexcept_t *flagp, int excepts) 55 { 56 fenv_t env; 57 58 __fnstenv(&env.__x87); 59 env.__x87.__status &= ~excepts; 60 env.__x87.__status |= *flagp & excepts; 61 __fldenv(&env.__x87); 62 63 __stmxcsr(&env.__mxcsr); 64 env.__mxcsr &= ~excepts; 65 env.__mxcsr |= *flagp & excepts; 66 __ldmxcsr(&env.__mxcsr); 67 68 return (0); 69 } 70 71 int 72 feraiseexcept(int excepts) 73 { 74 fexcept_t ex = excepts; 75 76 fesetexceptflag(&ex, excepts); 77 __fwait(); 78 return (0); 79 } 80 81 extern inline int fetestexcept(int __excepts); 82 extern inline int fegetround(void); 83 extern inline int fesetround(int __round); 84 85 int 86 fegetenv(fenv_t *envp) 87 { 88 89 __fnstenv(&envp->__x87); 90 __stmxcsr(&envp->__mxcsr); 91 /* 92 * fnstenv masks all exceptions, so we need to restore the 93 * control word to avoid this side effect. 94 */ 95 __fldcw(&envp->__x87.__control); 96 return (0); 97 } 98 99 int 100 feholdexcept(fenv_t *envp) 101 { 102 __uint32_t mxcsr; 103 104 __stmxcsr(&mxcsr); 105 __fnstenv(&envp->__x87); 106 __fnclex(); 107 envp->__mxcsr = mxcsr; 108 mxcsr &= ~FE_ALL_EXCEPT; 109 mxcsr |= FE_ALL_EXCEPT << _SSE_EMASK_SHIFT; 110 __ldmxcsr(&mxcsr); 111 return (0); 112 } 113 114 extern inline int fesetenv(const fenv_t *__envp); 115 116 int 117 feupdateenv(const fenv_t *envp) 118 { 119 __uint32_t mxcsr; 120 __uint16_t status; 121 122 __fnstsw(&status); 123 __stmxcsr(&mxcsr); 124 fesetenv(envp); 125 feraiseexcept((mxcsr | status) & FE_ALL_EXCEPT); 126 return (0); 127 } 128 129 int 130 __feenableexcept(int mask) 131 { 132 __uint32_t mxcsr, omask; 133 __uint16_t control; 134 135 mask &= FE_ALL_EXCEPT; 136 __fnstcw(&control); 137 __stmxcsr(&mxcsr); 138 omask = ~(control | mxcsr >> _SSE_EMASK_SHIFT) & FE_ALL_EXCEPT; 139 control &= ~mask; 140 __fldcw(&control); 141 mxcsr &= ~(mask << _SSE_EMASK_SHIFT); 142 __ldmxcsr(&mxcsr); 143 return (omask); 144 } 145 146 int 147 __fedisableexcept(int mask) 148 { 149 __uint32_t mxcsr, omask; 150 __uint16_t control; 151 152 mask &= FE_ALL_EXCEPT; 153 __fnstcw(&control); 154 __stmxcsr(&mxcsr); 155 omask = ~(control | mxcsr >> _SSE_EMASK_SHIFT) & FE_ALL_EXCEPT; 156 control |= mask; 157 __fldcw(&control); 158 mxcsr |= mask << _SSE_EMASK_SHIFT; 159 __ldmxcsr(&mxcsr); 160 return (omask); 161 } 162 163 __weak_reference(__feenableexcept, feenableexcept); 164 __weak_reference(__fedisableexcept, fedisableexcept); 165