1 /* $OpenBSD: fenv.h,v 1.4 2011/05/25 21:46:49 martynas Exp $ */ 2 /* $NetBSD: fenv.h,v 1.1 2010/07/31 21:47:54 joerg Exp $ */ 3 4 /*- 5 * Copyright (c) 2004-2005 David Schultz <das (at) FreeBSD.ORG> 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #ifndef _AMD64_FENV_H_ 31 #define _AMD64_FENV_H_ 32 33 #include <sys/cdefs.h> 34 35 /* 36 * Each symbol representing a floating point exception expands to an integer 37 * constant expression with values, such that bitwise-inclusive ORs of _all 38 * combinations_ of the constants result in distinct values. 39 * 40 * We use such values that allow direct bitwise operations on FPU/SSE registers. 41 */ 42 #define FE_INVALID 0x01 43 #define FE_DENORMAL 0x02 44 #define FE_DIVBYZERO 0x04 45 #define FE_OVERFLOW 0x08 46 #define FE_UNDERFLOW 0x10 47 #define FE_INEXACT 0x20 48 49 /* 50 * The following symbol is simply the bitwise-inclusive OR of all floating-point 51 * exception constants defined above. 52 */ 53 #define FE_ALL_EXCEPT (FE_INVALID | FE_DENORMAL | FE_DIVBYZERO | \ 54 FE_OVERFLOW | FE_UNDERFLOW | FE_INEXACT) 55 #define _SSE_MASK_SHIFT 7 56 57 /* 58 * Each symbol representing the rounding direction, expands to an integer 59 * constant expression whose value is distinct non-negative value. 60 * 61 * We use such values that allow direct bitwise operations on FPU/SSE registers. 62 */ 63 #define FE_TONEAREST 0x000 64 #define FE_DOWNWARD 0x400 65 #define FE_UPWARD 0x800 66 #define FE_TOWARDZERO 0xc00 67 68 /* 69 * The following symbol is simply the bitwise-inclusive OR of all floating-point 70 * rounding direction constants defined above. 71 */ 72 #define _X87_ROUND_MASK (FE_TONEAREST | FE_DOWNWARD | FE_UPWARD | \ 73 FE_TOWARDZERO) 74 #define _SSE_ROUND_SHIFT 3 75 76 /* 77 * fenv_t represents the entire floating-point environment. 78 */ 79 typedef struct { 80 struct { 81 unsigned int __control; /* Control word register */ 82 unsigned int __status; /* Status word register */ 83 unsigned int __tag; /* Tag word register */ 84 unsigned int __others[4]; /* EIP, Pointer Selector, etc */ 85 } __x87; 86 unsigned int __mxcsr; /* Control, status register */ 87 } fenv_t; 88 89 /* 90 * The following constant represents the default floating-point environment 91 * (that is, the one installed at program startup) and has type pointer to 92 * const-qualified fenv_t. 93 * 94 * It can be used as an argument to the functions within the <fenv.h> header 95 * that manage the floating-point environment, namely fesetenv() and 96 * feupdateenv(). 97 */ 98 __BEGIN_DECLS 99 extern fenv_t __fe_dfl_env; 100 __END_DECLS 101 #define FE_DFL_ENV ((const fenv_t *)&__fe_dfl_env) 102 103 /* 104 * fexcept_t represents the floating-point status flags collectively, including 105 * any status the implementation associates with the flags. 106 * 107 * A floating-point status flag is a system variable whose value is set (but 108 * never cleared) when a floating-point exception is raised, which occurs as a 109 * side effect of exceptional floating-point arithmetic to provide auxiliary 110 * information. 111 * 112 * A floating-point control mode is a system variable whose value may be set by 113 * the user to affect the subsequent behavior of floating-point arithmetic. 114 */ 115 typedef unsigned int fexcept_t; 116 117 #endif /* !_AMD64_FENV_H_ */ 118