projects / thirdparty / gcc.git / blame
| Commit | Line | Data |
|---|---|---|
| ed3cb497 PN |
1 | // Exception Handling support header for -*- C++ -*- |
| 2 | ||
| 99dee823 | 3 | // Copyright (C) 2016-2021 Free Software Foundation, Inc. |
| ed3cb497 PN |
4 | // |
| 5 | // This file is part of GCC. | |
| 6 | // | |
| 7 | // GCC is free software; you can redistribute it and/or modify | |
| 8 | // it under the terms of the GNU General Public License as published by | |
| 9 | // the Free Software Foundation; either version 3, or (at your option) | |
| 10 | // any later version. | |
| 11 | // | |
| 12 | // GCC is distributed in the hope that it will be useful, | |
| 13 | // but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 14 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 15 | // GNU General Public License for more details. | |
| 16 | // | |
| 17 | // Under Section 7 of GPL version 3, you are granted additional | |
| 18 | // permissions described in the GCC Runtime Library Exception, version | |
| 19 | // 3.1, as published by the Free Software Foundation. | |
| 20 | ||
| 21 | // You should have received a copy of the GNU General Public License and | |
| 22 | // a copy of the GCC Runtime Library Exception along with this program; | |
| 23 | // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see | |
| 24 | // <http://www.gnu.org/licenses/>. | |
| 25 | ||
| 26 | /** @file eh_atomics.h | |
| 27 | * This is an internal header file, included by library source files. | |
| 28 | * Do not attempt to use it directly. | |
| 29 | */ | |
| 30 | ||
| 31 | #ifndef _EH_ATOMICS_H | |
| 32 | #define _EH_ATOMICS_H 1 | |
| 33 | ||
| 34 | #include <bits/c++config.h> | |
| 35 | #include <bits/atomic_word.h> | |
| 36 | #include <bits/atomic_lockfree_defines.h> | |
| 37 | #if ATOMIC_INT_LOCK_FREE <= 1 | |
| 38 | # include <ext/atomicity.h> | |
| 39 | #endif | |
| 40 | ||
| 41 | #pragma GCC visibility push(default) | |
| 42 | extern "C++" { | |
| 43 | namespace __gnu_cxx | |
| 44 | { | |
| 45 | void | |
| 46 | __eh_atomic_inc (_Atomic_word* __count) __attribute__((always_inline)); | |
| 47 | ||
| 48 | bool | |
| 49 | __eh_atomic_dec (_Atomic_word* __count) __attribute__((always_inline)); | |
| 50 | ||
| 51 | // Increments the count. | |
| 52 | inline void | |
| 53 | __eh_atomic_inc (_Atomic_word* __count) | |
| 54 | { | |
| 55 | #if ATOMIC_INT_LOCK_FREE > 1 | |
| 56 | __atomic_add_fetch (__count, 1, __ATOMIC_ACQ_REL); | |
| 57 | #else | |
| 58 | _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE (__count); | |
| 59 | __gnu_cxx::__atomic_add_dispatch (__count, 1); | |
| 60 | _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER (__count); | |
| 61 | #endif | |
| 62 | } | |
| 63 | ||
| 64 | // Decrements the count and returns true if it reached zero. | |
| 65 | inline bool | |
| 66 | __eh_atomic_dec (_Atomic_word* __count) | |
| 67 | { | |
| 68 | #if ATOMIC_INT_LOCK_FREE > 1 | |
| 69 | return __atomic_sub_fetch (__count, 1, __ATOMIC_ACQ_REL) == 0; | |
| 70 | #else | |
| 71 | _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE (__count); | |
| 72 | if (__gnu_cxx::__exchange_and_add_dispatch (__count, -1) == 1) | |
| 73 | { | |
| 74 | _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER (__count); | |
| 75 | return true; | |
| 76 | } | |
| 77 | return false; | |
| 78 | #endif | |
| 79 | } | |
| 80 | } // namespace __gnu_cxx | |
| 81 | } | |
| 82 | #pragma GCC visibility pop | |
| 83 | ||
| 84 | #endif // _EH_ATOMICS_H |