added boost::memory_order

3rdParty/boost/1.58.0/boost/memory_order.hpp

@@ -0,0 +1,57 @@
+#ifndef BOOST_MEMORY_ORDER_HPP_INCLUDED
+#define BOOST_MEMORY_ORDER_HPP_INCLUDED
+
+// MS compatible compilers support #pragma once
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma once
+#endif
+
+//  boost/memory_order.hpp
+//
+//  Defines enum boost::memory_order per the C++0x working draft
+//
+//  Copyright (c) 2008, 2009 Peter Dimov
+//
+//  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)
+
+
+namespace boost
+{
+
+//
+// Enum values are chosen so that code that needs to insert
+// a trailing fence for acquire semantics can use a single
+// test such as:
+//
+// if( mo & memory_order_acquire ) { ...fence... }
+//
+// For leading fences one can use:
+//
+// if( mo & memory_order_release ) { ...fence... }
+//
+// Architectures such as Alpha that need a fence on consume
+// can use:
+//
+// if( mo & ( memory_order_acquire | memory_order_consume ) ) { ...fence... }
+//
+// The values are also in the order of increasing "strength"
+// of the fences so that success/failure orders can be checked
+// efficiently in compare_exchange methods.
+//
+
+enum memory_order
+{
+    memory_order_relaxed = 0,
+    memory_order_consume = 1,
+    memory_order_acquire = 2,
+    memory_order_release = 4,
+    memory_order_acq_rel = 6, // acquire | release
+    memory_order_seq_cst = 14 // acq_rel | 8
+};
+
+} // namespace boost
+
+#endif // #ifndef BOOST_MEMORY_ORDER_HPP_INCLUDED