diff options
Diffstat (limited to 'sys/arch')
| -rw-r--r-- | sys/arch/amd64/include/fenv.h | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/sys/arch/amd64/include/fenv.h b/sys/arch/amd64/include/fenv.h new file mode 100644 index 00000000000..9f9af5f52bf --- /dev/null +++ b/sys/arch/amd64/include/fenv.h @@ -0,0 +1,105 @@ +/* $OpenBSD: fenv.h,v 1.1 2011/04/21 21:12:56 martynas Exp $ */ +/* $NetBSD: fenv.h,v 1.1 2010/07/31 21:47:54 joerg Exp $ */ + +/*- + * Copyright (c) 2004-2005 David Schultz <das (at) FreeBSD.ORG> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#ifndef _AMD64_FENV_H_ +#define _AMD64_FENV_H_ + +/* + * Each symbol representing a floating point exception expands to an integer + * constant expression with values, such that bitwise-inclusive ORs of _all + * combinations_ of the constants result in distinct values. + * + * We use such values that allow direct bitwise operations on FPU/SSE registers. + */ +#define FE_INVALID 0x01 +#define FE_DENORMAL 0x02 +#define FE_DIVBYZERO 0x04 +#define FE_OVERFLOW 0x08 +#define FE_UNDERFLOW 0x10 +#define FE_INEXACT 0x20 + +/* + * The following symbol is simply the bitwise-inclusive OR of all floating-point + * exception constants defined above. + */ +#define FE_ALL_EXCEPT \ + (FE_DIVBYZERO | FE_INEXACT | FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW) + +/* + * Each symbol representing the rounding direction, expands to an integer + * constant expression whose value is distinct non-negative value. + * + * We use such values that allow direct bitwise operations on FPU/SSE registers. + */ +#define FE_TONEAREST 0x000 +#define FE_DOWNWARD 0x400 +#define FE_UPWARD 0x800 +#define FE_TOWARDZERO 0xC00 + +/* + * As compared to the x87 control word, the SSE unit's control word + * has the rounding control bits offset by 3 and the exception mask + * bits offset by 7. + */ +#define _X87_ROUND_MASK 0xC00 +#define _SSE_ROUND_MASK (0xC00 << 3) +#define _SSE_ROUND_SHIFT 3 +#define _SSE_EMASK_SHIFT 7 + +/* + * fenv_t represents the entire floating-point environment + */ +typedef struct { + struct { + unsigned int __control; /* Control word register */ + unsigned int __status; /* Status word register */ + unsigned int __tag; /* Tag word register */ + unsigned int __others[4]; /* EIP, Pointer Selector, etc */ + } __x87; + unsigned int __mxcsr; /* Control, status register */ +} fenv_t; + +extern fenv_t __fe_dfl_env; +#define FE_DFL_ENV ((const fenv_t *) &__fe_dfl_env) + +/* + * fexcept_t represents the floating-point status flags collectively, including + * any status the implementation associates with the flags. + * + * A floating-point status flag is a system variable whose value is set (but + * never cleared) when a floating-point exception is raised, which occurs as a + * side effect of exceptional floating-point arithmetic to provide auxiliary + * information. + * + * A floating-point control mode is a system variable whose value may be set by + * the user to affect the subsequent behavior of floating-point arithmetic. + */ +typedef unsigned int fexcept_t; + +#endif /* ! _AMD64_FENV_H_ */ |