Squashed 'third_party/boostorg/atomic/' content from commit 19eecf8
Change-Id: I4723a39ab79969b4c0d7b7e67a4143c4e02992ed
git-subtree-dir: third_party/boostorg/atomic
git-subtree-split: 19eecf893c665410de63ab6ebb8549f405703e80
diff --git a/include/boost/atomic/detail/pause.hpp b/include/boost/atomic/detail/pause.hpp
new file mode 100644
index 0000000..37aa5ca
--- /dev/null
+++ b/include/boost/atomic/detail/pause.hpp
@@ -0,0 +1,43 @@
+/*
+ * 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)
+ *
+ * (C) Copyright 2013 Tim Blechmann
+ * (C) Copyright 2013 Andrey Semashev
+ */
+
+#ifndef BOOST_ATOMIC_DETAIL_PAUSE_HPP_INCLUDED_
+#define BOOST_ATOMIC_DETAIL_PAUSE_HPP_INCLUDED_
+
+#include <boost/atomic/detail/config.hpp>
+
+#ifdef BOOST_HAS_PRAGMA_ONCE
+#pragma once
+#endif
+
+#if defined(_MSC_VER) && (defined(_M_AMD64) || defined(_M_IX86))
+extern "C" void _mm_pause(void);
+#if defined(BOOST_MSVC)
+#pragma intrinsic(_mm_pause)
+#endif
+#endif
+
+namespace boost {
+namespace atomics {
+namespace detail {
+
+BOOST_FORCEINLINE void pause() BOOST_NOEXCEPT
+{
+#if defined(_MSC_VER) && (defined(_M_AMD64) || defined(_M_IX86))
+ _mm_pause();
+#elif defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
+ __asm__ __volatile__("pause;");
+#endif
+}
+
+} // namespace detail
+} // namespace atomics
+} // namespace boost
+
+#endif // BOOST_ATOMIC_DETAIL_PAUSE_HPP_INCLUDED_