1 // <atomic> compatibility -*- C++ -*-
3 // Copyright (C) 2008-2022 Free Software Foundation, Inc.
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
29 // XXX GLIBCXX_ABI Deprecated
32 #ifdef _GLIBCXX_SHARED
38 #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
42 static std::mutex atomic_mutex
;
47 std::__atomic_flag_base flag_table
[ 1 << LOGSIZE
] =
49 ATOMIC_FLAG_INIT
, ATOMIC_FLAG_INIT
, ATOMIC_FLAG_INIT
, ATOMIC_FLAG_INIT
,
50 ATOMIC_FLAG_INIT
, ATOMIC_FLAG_INIT
, ATOMIC_FLAG_INIT
, ATOMIC_FLAG_INIT
,
51 ATOMIC_FLAG_INIT
, ATOMIC_FLAG_INIT
, ATOMIC_FLAG_INIT
, ATOMIC_FLAG_INIT
,
52 ATOMIC_FLAG_INIT
, ATOMIC_FLAG_INIT
, ATOMIC_FLAG_INIT
, ATOMIC_FLAG_INIT
,
54 } // anonymous namespace
56 namespace std
_GLIBCXX_VISIBILITY(default)
58 _GLIBCXX_BEGIN_NAMESPACE_VERSION
63 struct atomic_flag
: public __atomic_flag_base
66 test_and_set(memory_order
) noexcept
;
69 clear(memory_order
) noexcept
;
73 atomic_flag::test_and_set(memory_order
) noexcept
75 #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
76 lock_guard
<mutex
> __lock(get_atomic_mutex());
84 atomic_flag::clear(memory_order
) noexcept
86 #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
87 lock_guard
<mutex
> __lock(get_atomic_mutex());
91 } // namespace __atomic0
93 _GLIBCXX_BEGIN_EXTERN_C
96 atomic_flag_test_and_set_explicit(__atomic_flag_base
* __a
,
97 memory_order __m
) _GLIBCXX_NOTHROW
99 atomic_flag
* d
= static_cast<atomic_flag
*>(__a
);
100 return d
->test_and_set(__m
);
104 atomic_flag_clear_explicit(__atomic_flag_base
* __a
,
105 memory_order __m
) _GLIBCXX_NOTHROW
107 atomic_flag
* d
= static_cast<atomic_flag
*>(__a
);
108 return d
->clear(__m
);
112 __atomic_flag_wait_explicit(__atomic_flag_base
* __a
,
113 memory_order __x
) _GLIBCXX_NOTHROW
115 while (atomic_flag_test_and_set_explicit(__a
, __x
))
119 _GLIBCXX_CONST __atomic_flag_base
*
120 __atomic_flag_for_address(const volatile void* __z
) _GLIBCXX_NOTHROW
122 uintptr_t __u
= reinterpret_cast<uintptr_t>(__z
);
123 __u
+= (__u
>> 2) + (__u
<< 4);
124 __u
+= (__u
>> 7) + (__u
<< 5);
125 __u
+= (__u
>> 17) + (__u
<< 13);
126 if (sizeof(uintptr_t) > 4)
128 __u
&= ~((~uintptr_t(0)) << LOGSIZE
);
129 return flag_table
+ __u
;
132 _GLIBCXX_END_EXTERN_C
134 _GLIBCXX_END_NAMESPACE_VERSION
139 // XXX GLIBCXX_ABI Deprecated
141 // <atomic> signature changes
143 // The rename syntax for default exported names is
144 // asm (".symver name1,exportedname@GLIBCXX_3.4")
145 // asm (".symver name2,exportedname@@GLIBCXX_3.4.5")
146 // In the future, GLIBCXX_ABI > 6 should remove all uses of
147 // _GLIBCXX_*_SYMVER macros in this file.
149 #if defined(_GLIBCXX_SYMVER_GNU) && defined(_GLIBCXX_SHARED) \
150 && defined(_GLIBCXX_HAVE_AS_SYMVER_DIRECTIVE) \
151 && defined(_GLIBCXX_HAVE_SYMVER_SYMBOL_RENAMING_RUNTIME_SUPPORT)
153 #define _GLIBCXX_ASM_SYMVER(cur, old, version) \
154 asm (".symver " #cur "," #old "@@" #version);
156 _GLIBCXX_ASM_SYMVER(_ZNSt9__atomic011atomic_flag5clearESt12memory_order
, _ZNVSt9__atomic011atomic_flag5clearESt12memory_order
, GLIBCXX_3
.4
.11)
158 _GLIBCXX_ASM_SYMVER(_ZNSt9__atomic011atomic_flag12test_and_setESt12memory_order
, _ZNVSt9__atomic011atomic_flag12test_and_setESt12memory_order
, GLIBCXX_3
.4
.11)