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authorBoris Kolpackov <boris@codesynthesis.com>2011-06-28 17:17:23 +0200
committerBoris Kolpackov <boris@codesynthesis.com>2011-06-28 17:17:23 +0200
commitb51965dddbed68f23c5e8c169c23c794313ce5f6 (patch)
tree37bbdf4e5b1cdd34ea0694a5abd1483d1de2b3af /cutl/details/boost/smart_ptr/detail/atomic_count_gcc_x86.hpp
parent5f06e7e30e4f511ce2fb27c5feefa6aeb6f00841 (diff)
Add boost subset as an implementation detail
Diffstat (limited to 'cutl/details/boost/smart_ptr/detail/atomic_count_gcc_x86.hpp')
-rw-r--r--cutl/details/boost/smart_ptr/detail/atomic_count_gcc_x86.hpp77
1 files changed, 77 insertions, 0 deletions
diff --git a/cutl/details/boost/smart_ptr/detail/atomic_count_gcc_x86.hpp b/cutl/details/boost/smart_ptr/detail/atomic_count_gcc_x86.hpp
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+++ b/cutl/details/boost/smart_ptr/detail/atomic_count_gcc_x86.hpp
@@ -0,0 +1,77 @@
+#ifndef BOOST_SMART_PTR_DETAIL_ATOMIC_COUNT_GCC_X86_HPP_INCLUDED
+#define BOOST_SMART_PTR_DETAIL_ATOMIC_COUNT_GCC_X86_HPP_INCLUDED
+
+//
+// boost/detail/atomic_count_gcc_x86.hpp
+//
+// atomic_count for g++ on 486+/AMD64
+//
+// Copyright 2007 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 cutl_details_boost
+{
+
+namespace detail
+{
+
+class atomic_count
+{
+public:
+
+ explicit atomic_count( long v ) : value_( static_cast< int >( v ) ) {}
+
+ long operator++()
+ {
+ return atomic_exchange_and_add( &value_, +1 ) + 1;
+ }
+
+ long operator--()
+ {
+ return atomic_exchange_and_add( &value_, -1 ) - 1;
+ }
+
+ operator long() const
+ {
+ return atomic_exchange_and_add( &value_, 0 );
+ }
+
+private:
+
+ atomic_count(atomic_count const &);
+ atomic_count & operator=(atomic_count const &);
+
+ mutable int value_;
+
+private:
+
+ static int atomic_exchange_and_add( int * pw, int dv )
+ {
+ // int r = *pw;
+ // *pw += dv;
+ // return r;
+
+ int r;
+
+ __asm__ __volatile__
+ (
+ "lock\n\t"
+ "xadd %1, %0":
+ "+m"( *pw ), "=r"( r ): // outputs (%0, %1)
+ "1"( dv ): // inputs (%2 == %1)
+ "memory", "cc" // clobbers
+ );
+
+ return r;
+ }
+};
+
+} // namespace detail
+
+} // namespace cutl_details_boost
+
+#endif // #ifndef BOOST_SMART_PTR_DETAIL_ATOMIC_COUNT_GCC_X86_HPP_INCLUDED