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diff --git a/libcutl/cutl/details/boost/smart_ptr/detail/spinlock_gcc_arm.hpp b/libcutl/cutl/details/boost/smart_ptr/detail/spinlock_gcc_arm.hpp
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+#ifndef BOOST_SMART_PTR_DETAIL_SPINLOCK_GCC_ARM_HPP_INCLUDED
+#define BOOST_SMART_PTR_DETAIL_SPINLOCK_GCC_ARM_HPP_INCLUDED
+
+//
+// Copyright (c) 2008, 2011 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 <cutl/details/boost/smart_ptr/detail/yield_k.hpp>
+
+#if defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) || defined(__ARM_ARCH_7EM__) || defined(__ARM_ARCH_7S__)
+
+# define BOOST_SP_ARM_BARRIER "dmb"
+# define BOOST_SP_ARM_HAS_LDREX
+
+#elif defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__)
+
+# define BOOST_SP_ARM_BARRIER "mcr p15, 0, r0, c7, c10, 5"
+# define BOOST_SP_ARM_HAS_LDREX
+
+#else
+
+# define BOOST_SP_ARM_BARRIER ""
+
+#endif
+
+namespace cutl_details_boost
+{
+
+namespace detail
+{
+
+class spinlock
+{
+public:
+
+ int v_;
+
+public:
+
+ bool try_lock()
+ {
+ int r;
+
+#ifdef BOOST_SP_ARM_HAS_LDREX
+
+ __asm__ __volatile__(
+ "ldrex %0, [%2]; \n"
+ "cmp %0, %1; \n"
+ "strexne %0, %1, [%2]; \n"
+ BOOST_SP_ARM_BARRIER :
+ "=&r"( r ): // outputs
+ "r"( 1 ), "r"( &v_ ): // inputs
+ "memory", "cc" );
+
+#else
+
+ __asm__ __volatile__(
+ "swp %0, %1, [%2];\n"
+ BOOST_SP_ARM_BARRIER :
+ "=&r"( r ): // outputs
+ "r"( 1 ), "r"( &v_ ): // inputs
+ "memory", "cc" );
+
+#endif
+
+ return r == 0;
+ }
+
+ void lock()
+ {
+ for( unsigned k = 0; !try_lock(); ++k )
+ {
+ cutl_details_boost::detail::yield( k );
+ }
+ }
+
+ void unlock()
+ {
+ __asm__ __volatile__( BOOST_SP_ARM_BARRIER ::: "memory" );
+ *const_cast< int volatile* >( &v_ ) = 0;
+ }
+
+public:
+
+ class scoped_lock
+ {
+ private:
+
+ spinlock & sp_;
+
+ scoped_lock( scoped_lock const & );
+ scoped_lock & operator=( scoped_lock const & );
+
+ public:
+
+ explicit scoped_lock( spinlock & sp ): sp_( sp )
+ {
+ sp.lock();
+ }
+
+ ~scoped_lock()
+ {
+ sp_.unlock();
+ }
+ };
+};
+
+} // namespace detail
+} // namespace cutl_details_boost
+
+#define BOOST_DETAIL_SPINLOCK_INIT {0}
+
+#undef BOOST_SP_ARM_BARRIER
+#undef BOOST_SP_ARM_HAS_LDREX
+
+#endif // #ifndef BOOST_SMART_PTR_DETAIL_SPINLOCK_GCC_ARM_HPP_INCLUDED