1 files changed, 38 insertions, 3 deletions
diff --git a/cutl/details/boost/smart_ptr/detail/spinlock_gcc_arm.hpp b/cutl/details/boost/smart_ptr/detail/spinlock_gcc_arm.hpp
index cfee653..752c830 100644
--- a/cutl/details/boost/smart_ptr/detail/spinlock_gcc_arm.hpp
+++ b/cutl/details/boost/smart_ptr/detail/spinlock_gcc_arm.hpp
@@ -2,7 +2,7 @@
 #define BOOST_SMART_PTR_DETAIL_SPINLOCK_GCC_ARM_HPP_INCLUDED
 
 //
-//  Copyright (c) 2008 Peter Dimov
+//  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
@@ -11,6 +11,22 @@
 
 #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
 {
 
@@ -29,12 +45,28 @@ public:
     {
         int r;
 
+#ifdef BOOST_SP_ARM_HAS_LDREX
+
         __asm__ __volatile__(
-            "swp %0, %1, [%2]":
+            "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;
     }
 
@@ -48,7 +80,7 @@ public:
 
     void unlock()
     {
-        __asm__ __volatile__( "" ::: "memory" );
+        __asm__ __volatile__( BOOST_SP_ARM_BARRIER ::: "memory" );
         *const_cast< int volatile* >( &v_ ) = 0;
     }
 
@@ -82,4 +114,7 @@ public:
 
 #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