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