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-rw-r--r--3rdParty/Boost/src/boost/smart_ptr/detail/sp_counted_base_std_atomic.hpp137
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diff --git a/3rdParty/Boost/src/boost/smart_ptr/detail/sp_counted_base_std_atomic.hpp b/3rdParty/Boost/src/boost/smart_ptr/detail/sp_counted_base_std_atomic.hpp
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+++ b/3rdParty/Boost/src/boost/smart_ptr/detail/sp_counted_base_std_atomic.hpp
@@ -0,0 +1,137 @@
+#ifndef BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_STD_ATOMIC_HPP_INCLUDED
+#define BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_STD_ATOMIC_HPP_INCLUDED
+
+// MS compatible compilers support #pragma once
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma once
+#endif
+
+// detail/sp_counted_base_std_atomic.hpp - C++11 std::atomic
+//
+// Copyright (c) 2007, 2013 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
+
+#include <boost/detail/sp_typeinfo.hpp>
+#include <atomic>
+#include <cstdint>
+
+namespace boost
+{
+
+namespace detail
+{
+
+inline void atomic_increment( std::atomic_int_least32_t * pw )
+{
+ pw->fetch_add( 1, std::memory_order_relaxed );
+}
+
+inline std::int_least32_t atomic_decrement( std::atomic_int_least32_t * pw )
+{
+ return pw->fetch_sub( 1, std::memory_order_acq_rel );
+}
+
+inline std::int_least32_t atomic_conditional_increment( std::atomic_int_least32_t * pw )
+{
+ // long r = *pw;
+ // if( r != 0 ) ++*pw;
+ // return r;
+
+ std::int_least32_t r = pw->load( std::memory_order_relaxed );
+
+ for( ;; )
+ {
+ if( r == 0 )
+ {
+ return r;
+ }
+
+ if( pw->compare_exchange_weak( r, r + 1, std::memory_order_relaxed, std::memory_order_relaxed ) )
+ {
+ return r;
+ }
+ }
+}
+
+class sp_counted_base
+{
+private:
+
+ sp_counted_base( sp_counted_base const & );
+ sp_counted_base & operator= ( sp_counted_base const & );
+
+ std::atomic_int_least32_t use_count_; // #shared
+ std::atomic_int_least32_t weak_count_; // #weak + (#shared != 0)
+
+public:
+
+ sp_counted_base(): use_count_( 1 ), weak_count_( 1 )
+ {
+ }
+
+ virtual ~sp_counted_base() // nothrow
+ {
+ }
+
+ // dispose() is called when use_count_ drops to zero, to release
+ // the resources managed by *this.
+
+ virtual void dispose() = 0; // nothrow
+
+ // destroy() is called when weak_count_ drops to zero.
+
+ virtual void destroy() // nothrow
+ {
+ delete this;
+ }
+
+ virtual void * get_deleter( sp_typeinfo const & ti ) = 0;
+ virtual void * get_untyped_deleter() = 0;
+
+ void add_ref_copy()
+ {
+ atomic_increment( &use_count_ );
+ }
+
+ bool add_ref_lock() // true on success
+ {
+ return atomic_conditional_increment( &use_count_ ) != 0;
+ }
+
+ void release() // nothrow
+ {
+ if( atomic_decrement( &use_count_ ) == 1 )
+ {
+ dispose();
+ weak_release();
+ }
+ }
+
+ void weak_add_ref() // nothrow
+ {
+ atomic_increment( &weak_count_ );
+ }
+
+ void weak_release() // nothrow
+ {
+ if( atomic_decrement( &weak_count_ ) == 1 )
+ {
+ destroy();
+ }
+ }
+
+ long use_count() const // nothrow
+ {
+ return use_count_.load( std::memory_order_acquire );
+ }
+};
+
+} // namespace detail
+
+} // namespace boost
+
+#endif // #ifndef BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_STD_ATOMIC_HPP_INCLUDED