1 /* $OpenBSD: fenv.h,v 1.2 2011/04/23 21:54:20 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 /* 34 * Each symbol representing a floating point exception expands to an integer 35 * constant expression with values, such that bitwise-inclusive ORs of _all 36 * combinations_ of the constants result in distinct values. 37 * 38 * We use such values that allow direct bitwise operations on FPU/SSE registers. 39 */ 40 #define FE_INVALID 0x01 41 #define FE_DENORMAL 0x02 42 #define FE_DIVBYZERO 0x04 43 #define FE_OVERFLOW 0x08 44 #define FE_UNDERFLOW 0x10 45 #define FE_INEXACT 0x20 46 47 /* 48 * The following symbol is simply the bitwise-inclusive OR of all floating-point 49 * exception constants defined above. 50 */ 51 #define FE_ALL_EXCEPT \ 52 (FE_DIVBYZERO | FE_INEXACT | FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW | \ 53 FE_DENORMAL) 54 55 /* 56 * Each symbol representing the rounding direction, expands to an integer 57 * constant expression whose value is distinct non-negative value. 58 * 59 * We use such values that allow direct bitwise operations on FPU/SSE registers. 60 */ 61 #define FE_TONEAREST 0x000 62 #define FE_DOWNWARD 0x400 63 #define FE_UPWARD 0x800 64 #define FE_TOWARDZERO 0xC00 65 66 /* 67 * As compared to the x87 control word, the SSE unit's control word 68 * has the rounding control bits offset by 3 and the exception mask 69 * bits offset by 7. 70 */ 71 #define _X87_ROUND_MASK 0xC00 72 #define _SSE_ROUND_MASK (0xC00 << 3) 73 #define _SSE_ROUND_SHIFT 3 74 #define _SSE_EMASK_SHIFT 7 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 extern fenv_t __fe_dfl_env; 90 #define FE_DFL_ENV ((const fenv_t *) &__fe_dfl_env) 91 92 /* 93 * fexcept_t represents the floating-point status flags collectively, including 94 * any status the implementation associates with the flags. 95 * 96 * A floating-point status flag is a system variable whose value is set (but 97 * never cleared) when a floating-point exception is raised, which occurs as a 98 * side effect of exceptional floating-point arithmetic to provide auxiliary 99 * information. 100 * 101 * A floating-point control mode is a system variable whose value may be set by 102 * the user to affect the subsequent behavior of floating-point arithmetic. 103 */ 104 typedef unsigned int fexcept_t; 105 106 #endif /* ! _AMD64_FENV_H_ */ 107