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// <atomic> compatibility -*- C++ -*-
// Copyright (C) 2008-2022 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This 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 General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
#include <atomic>
#include <mutex>
// XXX GLIBCXX_ABI Deprecated
// gcc-4.7.0
#ifdef _GLIBCXX_SHARED
#define LOGSIZE 4
namespace
{
#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
std::mutex&
get_atomic_mutex()
{
static std::mutex atomic_mutex;
return atomic_mutex;
}
#endif
std::__atomic_flag_base flag_table[ 1 << LOGSIZE ] =
{
ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT,
ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT,
ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT,
ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT, ATOMIC_FLAG_INIT,
};
} // anonymous namespace
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
namespace __atomic0
{
struct atomic_flag : public __atomic_flag_base
{
bool
test_and_set(memory_order) noexcept;
void
clear(memory_order) noexcept;
};
bool
atomic_flag::test_and_set(memory_order) noexcept
{
#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
lock_guard<mutex> __lock(get_atomic_mutex());
#endif
bool result = _M_i;
_M_i = true;
return result;
}
void
atomic_flag::clear(memory_order) noexcept
{
#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
lock_guard<mutex> __lock(get_atomic_mutex());
#endif
_M_i = false;
}
} // namespace __atomic0
_GLIBCXX_BEGIN_EXTERN_C
bool
atomic_flag_test_and_set_explicit(__atomic_flag_base* __a,
memory_order __m) _GLIBCXX_NOTHROW
{
atomic_flag* d = static_cast<atomic_flag*>(__a);
return d->test_and_set(__m);
}
void
atomic_flag_clear_explicit(__atomic_flag_base* __a,
memory_order __m) _GLIBCXX_NOTHROW
{
atomic_flag* d = static_cast<atomic_flag*>(__a);
return d->clear(__m);
}
void
__atomic_flag_wait_explicit(__atomic_flag_base* __a,
memory_order __x) _GLIBCXX_NOTHROW
{
while (atomic_flag_test_and_set_explicit(__a, __x))
{ };
}
_GLIBCXX_CONST __atomic_flag_base*
__atomic_flag_for_address(const volatile void* __z) _GLIBCXX_NOTHROW
{
using guintptr_t = __UINTPTR_TYPE__;
guintptr_t __u = reinterpret_cast<guintptr_t>(__z);
__u += (__u >> 2) + (__u << 4);
__u += (__u >> 7) + (__u << 5);
__u += (__u >> 17) + (__u << 13);
if (sizeof(guintptr_t) > 4)
__u += (__u >> 31);
__u &= ~((~guintptr_t(0)) << LOGSIZE);
return flag_table + __u;
}
_GLIBCXX_END_EXTERN_C
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif
// XXX GLIBCXX_ABI Deprecated
// gcc-4.5.0
// <atomic> signature changes
// The rename syntax for default exported names is
// asm (".symver name1,exportedname@GLIBCXX_3.4")
// asm (".symver name2,exportedname@@GLIBCXX_3.4.5")
// In the future, GLIBCXX_ABI > 6 should remove all uses of
// _GLIBCXX_*_SYMVER macros in this file.
#if defined(_GLIBCXX_SYMVER_GNU) && defined(_GLIBCXX_SHARED) \
&& defined(_GLIBCXX_HAVE_AS_SYMVER_DIRECTIVE) \
&& defined(_GLIBCXX_HAVE_SYMVER_SYMBOL_RENAMING_RUNTIME_SUPPORT)
#define _GLIBCXX_ASM_SYMVER(cur, old, version) \
asm (".symver " #cur "," #old "@@" #version);
_GLIBCXX_ASM_SYMVER(_ZNSt9__atomic011atomic_flag5clearESt12memory_order, _ZNVSt9__atomic011atomic_flag5clearESt12memory_order, GLIBCXX_3.4.11)
_GLIBCXX_ASM_SYMVER(_ZNSt9__atomic011atomic_flag12test_and_setESt12memory_order, _ZNVSt9__atomic011atomic_flag12test_and_setESt12memory_order, GLIBCXX_3.4.11)
#endif