1/* $OpenBSD: fenv.h,v 1.1 2020/06/28 08:19:34 kettenis Exp $ */ 2 3/* 4 * Copyright (c) 2011 Martynas Venckus <martynas@openbsd.org> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19#ifndef _MACHINE_FENV_H_ 20#define _MACHINE_FENV_H_ 21 22/* 23 * Each symbol representing a floating point exception expands to an integer 24 * constant expression with values, such that bitwise-inclusive ORs of _all 25 * combinations_ of the constants result in distinct values. 26 * 27 * We use such values that allow direct bitwise operations on FPU registers. 28 */ 29#define FE_INEXACT 0x02000000 30#define FE_DIVBYZERO 0x04000000 31#define FE_UNDERFLOW 0x08000000 32#define FE_OVERFLOW 0x10000000 33#define FE_INVALID 0x20000000 34#define _FE_INVALID_SOFT 0x00000400 35#define _FE_INVALID_ALL 0x01f80700 36 37/* 38 * The following symbol is simply the bitwise-inclusive OR of all floating-point 39 * exception constants defined above. 40 */ 41#define FE_ALL_EXCEPT (FE_INEXACT | FE_DIVBYZERO | FE_UNDERFLOW | \ 42 FE_OVERFLOW | FE_INVALID) 43#define _MASK_SHIFT 22 44 45/* 46 * Each symbol representing the rounding direction, expands to an integer 47 * constant expression whose value is distinct non-negative value. 48 * 49 * We use such values that allow direct bitwise operations on FPU registers. 50 */ 51#define FE_TONEAREST 0x0 52#define FE_TOWARDZERO 0x1 53#define FE_UPWARD 0x2 54#define FE_DOWNWARD 0x3 55 56/* 57 * The following symbol is simply the bitwise-inclusive OR of all floating-point 58 * rounding direction constants defined above. 59 */ 60#define _ROUND_MASK (FE_TONEAREST | FE_TOWARDZERO | FE_UPWARD | \ 61 FE_DOWNWARD) 62 63/* 64 * fenv_t represents the entire floating-point environment. 65 */ 66typedef unsigned int fenv_t; 67 68/* 69 * The following constant represents the default floating-point environment 70 * (that is, the one installed at program startup) and has type pointer to 71 * const-qualified fenv_t. 72 * 73 * It can be used as an argument to the functions within the <fenv.h> header 74 * that manage the floating-point environment, namely fesetenv() and 75 * feupdateenv(). 76 */ 77__BEGIN_DECLS 78extern fenv_t __fe_dfl_env; 79__END_DECLS 80#define FE_DFL_ENV ((const fenv_t *)&__fe_dfl_env) 81 82/* 83 * fexcept_t represents the floating-point status flags collectively, including 84 * any status the implementation associates with the flags. 85 * 86 * A floating-point status flag is a system variable whose value is set (but 87 * never cleared) when a floating-point exception is raised, which occurs as a 88 * side effect of exceptional floating-point arithmetic to provide auxiliary 89 * information. 90 * 91 * A floating-point control mode is a system variable whose value may be set by 92 * the user to affect the subsequent behavior of floating-point arithmetic. 93 */ 94typedef unsigned int fexcept_t; 95 96#endif /* !_MACHINE_FENV_H_ */ 97