Squashed 'third_party/boostorg/atomic/' content from commit 19eecf8
Change-Id: I4723a39ab79969b4c0d7b7e67a4143c4e02992ed
git-subtree-dir: third_party/boostorg/atomic
git-subtree-split: 19eecf893c665410de63ab6ebb8549f405703e80
diff --git a/src/lockpool.cpp b/src/lockpool.cpp
new file mode 100644
index 0000000..a1292fa
--- /dev/null
+++ b/src/lockpool.cpp
@@ -0,0 +1,167 @@
+/*
+ * Distributed under the Boost Software License, Version 1.0.
+ * (See accompanying file LICENSE_1_0.txt or copy at
+ * http://www.boost.org/LICENSE_1_0.txt)
+ *
+ * Copyright (c) 2011 Helge Bahmann
+ * Copyright (c) 2013-2014 Andrey Semashev
+ */
+/*!
+ * \file lockpool.cpp
+ *
+ * This file contains implementation of the lockpool used to emulate atomic ops.
+ */
+
+#include <cstddef>
+#include <boost/config.hpp>
+#include <boost/assert.hpp>
+#include <boost/memory_order.hpp>
+#include <boost/atomic/capabilities.hpp>
+
+#if BOOST_ATOMIC_FLAG_LOCK_FREE == 2
+#include <boost/atomic/detail/operations_lockfree.hpp>
+#elif !defined(BOOST_HAS_PTHREADS)
+#error Boost.Atomic: Unsupported target platform, POSIX threads are required when native atomic operations are not available
+#else
+#include <pthread.h>
+#define BOOST_ATOMIC_USE_PTHREAD
+#endif
+
+#include <boost/atomic/detail/lockpool.hpp>
+#include <boost/atomic/detail/pause.hpp>
+
+#if defined(BOOST_MSVC)
+#pragma warning(push)
+// 'struct_name' : structure was padded due to __declspec(align())
+#pragma warning(disable: 4324)
+#endif
+
+namespace boost {
+namespace atomics {
+namespace detail {
+
+namespace {
+
+// Cache line size, in bytes
+// NOTE: This constant is made as a macro because some compilers (gcc 4.4 for one) don't allow enums or namespace scope constants in alignment attributes
+#if defined(__s390__) || defined(__s390x__)
+#define BOOST_ATOMIC_CACHE_LINE_SIZE 256
+#elif defined(powerpc) || defined(__powerpc__) || defined(__ppc__)
+#define BOOST_ATOMIC_CACHE_LINE_SIZE 128
+#else
+#define BOOST_ATOMIC_CACHE_LINE_SIZE 64
+#endif
+
+#if defined(BOOST_ATOMIC_USE_PTHREAD)
+typedef pthread_mutex_t lock_type;
+#else
+typedef atomics::detail::operations< 1u, false > lock_operations;
+typedef lock_operations::storage_type lock_type;
+#endif
+
+enum
+{
+ padding_size = (sizeof(lock_type) <= BOOST_ATOMIC_CACHE_LINE_SIZE ?
+ (BOOST_ATOMIC_CACHE_LINE_SIZE - sizeof(lock_type)) :
+ (BOOST_ATOMIC_CACHE_LINE_SIZE - sizeof(lock_type) % BOOST_ATOMIC_CACHE_LINE_SIZE))
+};
+
+template< unsigned int PaddingSize >
+struct BOOST_ALIGNMENT(BOOST_ATOMIC_CACHE_LINE_SIZE) padded_lock
+{
+ lock_type lock;
+ // The additional padding is needed to avoid false sharing between locks
+ char padding[PaddingSize];
+};
+
+template< >
+struct BOOST_ALIGNMENT(BOOST_ATOMIC_CACHE_LINE_SIZE) padded_lock< 0u >
+{
+ lock_type lock;
+};
+
+typedef padded_lock< padding_size > padded_lock_t;
+
+static padded_lock_t g_lock_pool[41]
+#if defined(BOOST_ATOMIC_USE_PTHREAD)
+=
+{
+ { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+ { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+ { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+ { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+ { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+ { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+ { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+ { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+ { PTHREAD_MUTEX_INITIALIZER }
+}
+#endif
+;
+
+} // namespace
+
+
+#if !defined(BOOST_ATOMIC_USE_PTHREAD)
+
+// NOTE: This function must NOT be inline. Otherwise MSVC 9 will sometimes generate broken code for modulus operation which result in crashes.
+BOOST_ATOMIC_DECL lockpool::scoped_lock::scoped_lock(const volatile void* addr) BOOST_NOEXCEPT :
+ m_lock(&g_lock_pool[reinterpret_cast< std::size_t >(addr) % (sizeof(g_lock_pool) / sizeof(*g_lock_pool))].lock)
+{
+ while (lock_operations::test_and_set(*static_cast< lock_type* >(m_lock), memory_order_acquire))
+ {
+ do
+ {
+ atomics::detail::pause();
+ }
+ while (!!lock_operations::load(*static_cast< lock_type* >(m_lock), memory_order_relaxed));
+ }
+}
+
+BOOST_ATOMIC_DECL lockpool::scoped_lock::~scoped_lock() BOOST_NOEXCEPT
+{
+ lock_operations::clear(*static_cast< lock_type* >(m_lock), memory_order_release);
+}
+
+BOOST_ATOMIC_DECL void signal_fence() BOOST_NOEXCEPT;
+
+#else // !defined(BOOST_ATOMIC_USE_PTHREAD)
+
+BOOST_ATOMIC_DECL lockpool::scoped_lock::scoped_lock(const volatile void* addr) BOOST_NOEXCEPT :
+ m_lock(&g_lock_pool[reinterpret_cast< std::size_t >(addr) % (sizeof(g_lock_pool) / sizeof(*g_lock_pool))].lock)
+{
+ BOOST_VERIFY(pthread_mutex_lock(static_cast< pthread_mutex_t* >(m_lock)) == 0);
+}
+
+BOOST_ATOMIC_DECL lockpool::scoped_lock::~scoped_lock() BOOST_NOEXCEPT
+{
+ BOOST_VERIFY(pthread_mutex_unlock(static_cast< pthread_mutex_t* >(m_lock)) == 0);
+}
+
+#endif // !defined(BOOST_ATOMIC_USE_PTHREAD)
+
+BOOST_ATOMIC_DECL void lockpool::thread_fence() BOOST_NOEXCEPT
+{
+#if BOOST_ATOMIC_THREAD_FENCE > 0
+ atomics::detail::thread_fence(memory_order_seq_cst);
+#else
+ // Emulate full fence by locking/unlocking a mutex
+ scoped_lock lock(0);
+#endif
+}
+
+BOOST_ATOMIC_DECL void lockpool::signal_fence() BOOST_NOEXCEPT
+{
+ // This function is intentionally non-inline, even if empty. This forces the compiler to treat its call as a compiler barrier.
+#if BOOST_ATOMIC_SIGNAL_FENCE > 0
+ atomics::detail::signal_fence(memory_order_seq_cst);
+#endif
+}
+
+} // namespace detail
+} // namespace atomics
+} // namespace boost
+
+#if defined(BOOST_MSVC)
+#pragma warning(pop)
+#endif