1/* Copyright (C) 2004-2026 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