glibc/sysdeps/s390/fpu/bits/fenv.h
2012-02-09 23:18:22 +00:00

82 lines
2.5 KiB
C

/* Copyright (C) 2000, 2012 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Denis Joseph Barrow <djbarrow@de.ibm.com>.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#ifndef _FENV_H
# error "Never use <bits/fenv.h> directly; include <fenv.h> instead."
#endif
/* Define bits representing the exception. We use the bit positions
of the appropriate bits in the FPU control word. */
enum
{
FE_INVALID = 0x80,
#define FE_INVALID FE_INVALID
FE_DIVBYZERO = 0x40,
#define FE_DIVBYZERO FE_DIVBYZERO
FE_OVERFLOW = 0x20,
#define FE_OVERFLOW FE_OVERFLOW
FE_UNDERFLOW = 0x10,
#define FE_UNDERFLOW FE_UNDERFLOW
FE_INEXACT = 0x08
#define FE_INEXACT FE_INEXACT
};
/* We dont use the y bit of the DXC in the floating point control register
as glibc has no FE encoding for fe inexact incremented
or fe inexact truncated.
We currently use the flag bits in the fpc
as these are sticky for feholdenv & feupdatenv as it is defined
in the HP Manpages. */
#define FE_ALL_EXCEPT \
(FE_INEXACT | FE_DIVBYZERO | FE_UNDERFLOW | FE_OVERFLOW | FE_INVALID)
enum
{
FE_TONEAREST = 0,
#define FE_TONEAREST FE_TONEAREST
FE_DOWNWARD = 0x3,
#define FE_DOWNWARD FE_DOWNWARD
FE_UPWARD = 0x2,
#define FE_UPWARD FE_UPWARD
FE_TOWARDZERO = 0x1
#define FE_TOWARDZERO FE_TOWARDZERO
};
/* Type representing exception flags. */
typedef unsigned int fexcept_t; /* size of fpc */
/* Type representing floating-point environment. This function corresponds
to the layout of the block written by the `fstenv'. */
typedef struct
{
fexcept_t fpc;
void *ieee_instruction_pointer;
/* failing instruction for ieee exceptions */
} fenv_t;
/* If the default argument is used we use this value. */
#define FE_DFL_ENV ((const fenv_t *) -1)
#ifdef __USE_GNU
/* Floating-point environment where none of the exceptions are masked. */
# define FE_NOMASK_ENV ((const fenv_t *) -2)
#endif