Add atomic_count_gcc_atomic.hpp

include/boost/smart_ptr/detail/atomic_count.hpp

@@ -43,8 +43,9 @@
 //    Memory Ordering: acquire/release
 //
 
-#include <boost/config.hpp>
+#include <boost/smart_ptr/detail/sp_has_gcc_intrinsics.hpp>
 #include <boost/smart_ptr/detail/sp_has_sync_intrinsics.hpp>
+#include <boost/config.hpp>
 
 #if defined( BOOST_AC_DISABLE_THREADS )
 # include <boost/smart_ptr/detail/atomic_count_nt.hpp>
@@ -73,6 +74,9 @@
 #elif defined( BOOST_DISABLE_THREADS ) && !defined( BOOST_SP_ENABLE_THREADS ) && !defined( BOOST_DISABLE_WIN32 )
 # include <boost/smart_ptr/detail/atomic_count_nt.hpp>
 
+#elif defined( BOOST_SP_HAS_GCC_INTRINSICS )
+# include <boost/smart_ptr/detail/atomic_count_gcc_atomic.hpp>
+
 #elif !defined( BOOST_NO_CXX11_HDR_ATOMIC )
 # include <boost/smart_ptr/detail/atomic_count_std_atomic.hpp>
 

include/boost/smart_ptr/detail/atomic_count_gcc_atomic.hpp

@@ -0,0 +1,63 @@
+#ifndef BOOST_SMART_PTR_DETAIL_ATOMIC_COUNT_GCC_ATOMIC_HPP_INCLUDED
+#define BOOST_SMART_PTR_DETAIL_ATOMIC_COUNT_GCC_ATOMIC_HPP_INCLUDED
+
+// boost/detail/atomic_count_gcc_atomic.hpp
+//
+// atomic_count for g++ 4.7+
+//
+// Copyright 2007, 2020 Peter Dimov
+//
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/cstdint.hpp>
+
+#if defined(BOOST_SP_REPORT_IMPLEMENTATION)
+
+#include <boost/config/pragma_message.hpp>
+BOOST_PRAGMA_MESSAGE("Using __atomic atomic_count")
+
+#endif
+
+namespace boost
+{
+
+namespace detail
+{
+
+class atomic_count
+{
+public:
+
+    explicit atomic_count( long v ): value_( static_cast< boost::int_least32_t >( v ) )
+    {
+    }
+
+    long operator++()
+    {
+        return __atomic_add_fetch( &value_, +1, __ATOMIC_ACQ_REL );
+    }
+
+    long operator--()
+    {
+        return __atomic_add_fetch( &value_, -1, __ATOMIC_ACQ_REL );
+    }
+
+    operator long() const
+    {
+        return __atomic_load_n( &value_, __ATOMIC_ACQUIRE );
+    }
+
+private:
+
+    atomic_count(atomic_count const &);
+    atomic_count & operator=(atomic_count const &);
+
+    boost::int_least32_t value_;
+};
+
+} // namespace detail
+
+} // namespace boost
+
+#endif // #ifndef BOOST_SMART_PTR_DETAIL_ATOMIC_COUNT_GCC_ATOMIC_HPP_INCLUDED

include/boost/smart_ptr/detail/atomic_count_sync.hpp

@@ -38,7 +38,7 @@ class atomic_count
 {
 public:
 
-    explicit atomic_count( long v ) : value_( static_cast< boost::int_least32_t >( v ) )
+    explicit atomic_count( long v ): value_( static_cast< boost::int_least32_t >( v ) )
     {
     }