atomic/detail/fence_arch_ops_gcc_aarch64.hpp

0001 /*
0002  * Distributed under the Boost Software License, Version 1.0.
0003  * (See accompanying file LICENSE_1_0.txt or copy at
0004  * http://www.boost.org/LICENSE_1_0.txt)
0005  *
0006  * Copyright (c) 2020 Andrey Semashev
0007  */
0008 /*!
0009  * \file   atomic/detail/fence_arch_ops_gcc_aarch64.hpp
0010  *
0011  * This header contains implementation of the \c fence_arch_operations struct.
0012  */
0013
0014 #ifndef BOOST_ATOMIC_DETAIL_FENCE_ARCH_OPS_GCC_AARCH64_HPP_INCLUDED_
0015 #define BOOST_ATOMIC_DETAIL_FENCE_ARCH_OPS_GCC_AARCH64_HPP_INCLUDED_
0016
0017 #include <boost/memory_order.hpp>
0018 #include <boost/atomic/detail/config.hpp>
0019 #include <boost/atomic/detail/header.hpp>
0020
0021 #ifdef BOOST_HAS_PRAGMA_ONCE
0022 #pragma once
0023 #endif
0024
0025 namespace boost {
0026 namespace atomics {
0027 namespace detail {
0028
0029 //! Fence operations for AArch64
0030 struct fence_arch_operations_gcc_aarch64
0031 {
0032     static BOOST_FORCEINLINE void thread_fence(memory_order order) BOOST_NOEXCEPT
0033     {
0034         if (order != memory_order_relaxed)
0035         {
0036             if (order == memory_order_consume || order == memory_order_acquire)
0037                 __asm__ __volatile__ ("dmb ishld\n\t" ::: "memory");
0038             else
0039                 __asm__ __volatile__ ("dmb ish\n\t" ::: "memory");
0040         }
0041     }
0042
0043     static BOOST_FORCEINLINE void signal_fence(memory_order order) BOOST_NOEXCEPT
0044     {
0045         if (order != memory_order_relaxed)
0046             __asm__ __volatile__ ("" ::: "memory");
0047     }
0048 };
0049
0050 typedef fence_arch_operations_gcc_aarch64 fence_arch_operations;
0051
0052 } // namespace detail
0053 } // namespace atomics
0054 } // namespace boost
0055
0056 #include <boost/atomic/detail/footer.hpp>
0057
0058 #endif // BOOST_ATOMIC_DETAIL_FENCE_ARCH_OPS_GCC_AARCH64_HPP_INCLUDED_