1/* Copyright (C) 2004-2025 Free Software Foundation, Inc.
 2
 3   This file is part of the GNU C Library.
 4
 5   The GNU C Library is free software; you can redistribute it and/or
 6   modify it under the terms of the GNU Lesser General Public License as
 7   published by the Free Software Foundation; either version 2.1 of the
 8   License, or (at your option) any later version.
 9
10   The GNU C Library is distributed in the hope that it will be useful,
11   but WITHOUT ANY WARRANTY; without even the implied warranty of
12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13   Lesser General Public License for more details.
14
15   You should have received a copy of the GNU Lesser General Public
16   License along with the GNU C Library; if not, see
17   <https://www.gnu.org/licenses/>.  */
18
19#ifndef _FENV_H
20# error "Never use <bits/fenv.h> directly; include <fenv.h> instead."
21#endif
22
23/* Define bits representing exceptions in the FPSR status word.  */
24enum
25  {
26    FE_INVALID =
27#define FE_INVALID	1
28      FE_INVALID,
29    FE_DIVBYZERO =
30#define FE_DIVBYZERO	2
31      FE_DIVBYZERO,
32    FE_OVERFLOW =
33#define FE_OVERFLOW	4
34      FE_OVERFLOW,
35    FE_UNDERFLOW =
36#define FE_UNDERFLOW	8
37      FE_UNDERFLOW,
38    FE_INEXACT =
39#define FE_INEXACT	16
40      FE_INEXACT,
41  };
42
43/* Amount to shift by to convert an exception bit in FPSR to a an
44   exception bit mask in FPCR.  */
45#define FE_EXCEPT_SHIFT	8
46
47/* All supported exceptions.  */
48#define FE_ALL_EXCEPT	\
49	(FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW | FE_INEXACT)
50
51/* Define bits representing rounding modes in the FPCR Rmode field.  */
52#define FE_TONEAREST  0x000000
53#define FE_UPWARD     0x400000
54#define FE_DOWNWARD   0x800000
55#define FE_TOWARDZERO 0xc00000
56
57/* Type representing exception flags. */
58typedef unsigned int fexcept_t;
59
60/* Type representing floating-point environment.  */
61typedef struct
62  {
63    unsigned int __fpcr;
64    unsigned int __fpsr;
65  }
66fenv_t;
67
68/* If the default argument is used we use this value.  */
69#define FE_DFL_ENV	((const fenv_t *) -1l)
70
71#ifdef __USE_GNU
72/* Floating-point environment where none of the exceptions are masked.  */
73# define FE_NOMASK_ENV  ((const fenv_t *) -2)
74#endif
75
76#if __GLIBC_USE (IEC_60559_BFP_EXT_C23)
77/* Type representing floating-point control modes.  */
78typedef unsigned int femode_t;
79
80/* Default floating-point control modes.  */
81# define FE_DFL_MODE	((const femode_t *) -1L)
82#endif