Chris@102: /*
Chris@102:  * Distributed under the Boost Software License, Version 1.0.
Chris@102:  * (See accompanying file LICENSE_1_0.txt or copy at
Chris@102:  * http://www.boost.org/LICENSE_1_0.txt)
Chris@102:  *
Chris@102:  * Copyright (c) 2009 Helge Bahmann
Chris@102:  * Copyright (c) 2012 Tim Blechmann
Chris@102:  * Copyright (c) 2014 Andrey Semashev
Chris@102:  */
Chris@102: /*!
Chris@102:  * \file   atomic/detail/ops_windows.hpp
Chris@102:  *
Chris@102:  * This header contains implementation of the \c operations template.
Chris@102:  *
Chris@102:  * This implementation is the most basic version for Windows. It should
Chris@102:  * work for any non-MSVC-like compilers as long as there are Interlocked WinAPI
Chris@102:  * functions available. This version is also used for WinCE.
Chris@102:  *
Chris@102:  * Notably, this implementation is not as efficient as other
Chris@102:  * versions based on compiler intrinsics.
Chris@102:  */
Chris@102: 
Chris@102: #ifndef BOOST_ATOMIC_DETAIL_OPS_WINDOWS_HPP_INCLUDED_
Chris@102: #define BOOST_ATOMIC_DETAIL_OPS_WINDOWS_HPP_INCLUDED_
Chris@102: 
Chris@102: #include <boost/memory_order.hpp>
Chris@102: #include <boost/type_traits/make_signed.hpp>
Chris@102: #include <boost/atomic/detail/config.hpp>
Chris@102: #include <boost/atomic/detail/interlocked.hpp>
Chris@102: #include <boost/atomic/detail/storage_type.hpp>
Chris@102: #include <boost/atomic/detail/operations_fwd.hpp>
Chris@102: #include <boost/atomic/capabilities.hpp>
Chris@102: #include <boost/atomic/detail/ops_msvc_common.hpp>
Chris@102: #include <boost/atomic/detail/ops_extending_cas_based.hpp>
Chris@102: 
Chris@102: #ifdef BOOST_HAS_PRAGMA_ONCE
Chris@102: #pragma once
Chris@102: #endif
Chris@102: 
Chris@102: namespace boost {
Chris@102: namespace atomics {
Chris@102: namespace detail {
Chris@102: 
Chris@102: struct windows_operations_base
Chris@102: {
Chris@102:     static BOOST_FORCEINLINE void hardware_full_fence() BOOST_NOEXCEPT
Chris@102:     {
Chris@102:         long tmp;
Chris@102:         BOOST_ATOMIC_INTERLOCKED_EXCHANGE(&tmp, 0);
Chris@102:     }
Chris@102: 
Chris@102:     static BOOST_FORCEINLINE void fence_before(memory_order) BOOST_NOEXCEPT
Chris@102:     {
Chris@102:         BOOST_ATOMIC_DETAIL_COMPILER_BARRIER();
Chris@102:     }
Chris@102: 
Chris@102:     static BOOST_FORCEINLINE void fence_after(memory_order) BOOST_NOEXCEPT
Chris@102:     {
Chris@102:         BOOST_ATOMIC_DETAIL_COMPILER_BARRIER();
Chris@102:     }
Chris@102: };
Chris@102: 
Chris@102: template< typename T, typename Derived >
Chris@102: struct windows_operations :
Chris@102:     public windows_operations_base
Chris@102: {
Chris@102:     typedef T storage_type;
Chris@102: 
Chris@102:     static BOOST_FORCEINLINE void store(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT
Chris@102:     {
Chris@102:         Derived::exchange(storage, v, order);
Chris@102:     }
Chris@102: 
Chris@102:     static BOOST_FORCEINLINE storage_type load(storage_type const volatile& storage, memory_order order) BOOST_NOEXCEPT
Chris@102:     {
Chris@102:         return Derived::fetch_add(const_cast< storage_type volatile& >(storage), (storage_type)0, order);
Chris@102:     }
Chris@102: 
Chris@102:     static BOOST_FORCEINLINE storage_type fetch_sub(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT
Chris@102:     {
Chris@102:         typedef typename make_signed< storage_type >::type signed_storage_type;
Chris@102:         return Derived::fetch_add(storage, static_cast< storage_type >(-static_cast< signed_storage_type >(v)), order);
Chris@102:     }
Chris@102: 
Chris@102:     static BOOST_FORCEINLINE bool compare_exchange_weak(
Chris@102:         storage_type volatile& storage, storage_type& expected, storage_type desired, memory_order success_order, memory_order failure_order) BOOST_NOEXCEPT
Chris@102:     {
Chris@102:         return Derived::compare_exchange_strong(storage, expected, desired, success_order, failure_order);
Chris@102:     }
Chris@102: 
Chris@102:     static BOOST_FORCEINLINE bool test_and_set(storage_type volatile& storage, memory_order order) BOOST_NOEXCEPT
Chris@102:     {
Chris@102:         return !!Derived::exchange(storage, (storage_type)1, order);
Chris@102:     }
Chris@102: 
Chris@102:     static BOOST_FORCEINLINE void clear(storage_type volatile& storage, memory_order order) BOOST_NOEXCEPT
Chris@102:     {
Chris@102:         store(storage, (storage_type)0, order);
Chris@102:     }
Chris@102: 
Chris@102:     static BOOST_FORCEINLINE bool is_lock_free(storage_type const volatile&) BOOST_NOEXCEPT
Chris@102:     {
Chris@102:         return true;
Chris@102:     }
Chris@102: };
Chris@102: 
Chris@102: template< bool Signed >
Chris@102: struct operations< 4u, Signed > :
Chris@102:     public windows_operations< typename make_storage_type< 4u, Signed >::type, operations< 4u, Signed > >
Chris@102: {
Chris@102:     typedef windows_operations< typename make_storage_type< 4u, Signed >::type, operations< 4u, Signed > > base_type;
Chris@102:     typedef typename base_type::storage_type storage_type;
Chris@102: 
Chris@102:     static BOOST_FORCEINLINE storage_type fetch_add(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT
Chris@102:     {
Chris@102:         base_type::fence_before(order);
Chris@102:         v = static_cast< storage_type >(BOOST_ATOMIC_INTERLOCKED_EXCHANGE_ADD(&storage, v));
Chris@102:         base_type::fence_after(order);
Chris@102:         return v;
Chris@102:     }
Chris@102: 
Chris@102:     static BOOST_FORCEINLINE storage_type exchange(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT
Chris@102:     {
Chris@102:         base_type::fence_before(order);
Chris@102:         v = static_cast< storage_type >(BOOST_ATOMIC_INTERLOCKED_EXCHANGE(&storage, v));
Chris@102:         base_type::fence_after(order);
Chris@102:         return v;
Chris@102:     }
Chris@102: 
Chris@102:     static BOOST_FORCEINLINE bool compare_exchange_strong(
Chris@102:         storage_type volatile& storage, storage_type& expected, storage_type desired, memory_order success_order, memory_order failure_order) BOOST_NOEXCEPT
Chris@102:     {
Chris@102:         storage_type previous = expected;
Chris@102:         base_type::fence_before(success_order);
Chris@102:         storage_type old_val = static_cast< storage_type >(BOOST_ATOMIC_INTERLOCKED_COMPARE_EXCHANGE(&storage, desired, previous));
Chris@102:         expected = old_val;
Chris@102:         // The success and failure fences are the same anyway
Chris@102:         base_type::fence_after(success_order);
Chris@102:         return (previous == old_val);
Chris@102:     }
Chris@102: 
Chris@102:     static BOOST_FORCEINLINE storage_type fetch_and(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT
Chris@102:     {
Chris@102: #if defined(BOOST_ATOMIC_INTERLOCKED_AND)
Chris@102:         base_type::fence_before(order);
Chris@102:         v = static_cast< storage_type >(BOOST_ATOMIC_INTERLOCKED_AND(&storage, v));
Chris@102:         base_type::fence_after(order);
Chris@102:         return v;
Chris@102: #else
Chris@102:         storage_type res = storage;
Chris@102:         while (!compare_exchange_strong(storage, res, res & v, order, memory_order_relaxed)) {}
Chris@102:         return res;
Chris@102: #endif
Chris@102:     }
Chris@102: 
Chris@102:     static BOOST_FORCEINLINE storage_type fetch_or(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT
Chris@102:     {
Chris@102: #if defined(BOOST_ATOMIC_INTERLOCKED_OR)
Chris@102:         base_type::fence_before(order);
Chris@102:         v = static_cast< storage_type >(BOOST_ATOMIC_INTERLOCKED_OR(&storage, v));
Chris@102:         base_type::fence_after(order);
Chris@102:         return v;
Chris@102: #else
Chris@102:         storage_type res = storage;
Chris@102:         while (!compare_exchange_strong(storage, res, res | v, order, memory_order_relaxed)) {}
Chris@102:         return res;
Chris@102: #endif
Chris@102:     }
Chris@102: 
Chris@102:     static BOOST_FORCEINLINE storage_type fetch_xor(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT
Chris@102:     {
Chris@102: #if defined(BOOST_ATOMIC_INTERLOCKED_XOR)
Chris@102:         base_type::fence_before(order);
Chris@102:         v = static_cast< storage_type >(BOOST_ATOMIC_INTERLOCKED_XOR(&storage, v));
Chris@102:         base_type::fence_after(order);
Chris@102:         return v;
Chris@102: #else
Chris@102:         storage_type res = storage;
Chris@102:         while (!compare_exchange_strong(storage, res, res ^ v, order, memory_order_relaxed)) {}
Chris@102:         return res;
Chris@102: #endif
Chris@102:     }
Chris@102: };
Chris@102: 
Chris@102: template< bool Signed >
Chris@102: struct operations< 1u, Signed > :
Chris@102:     public extending_cas_based_operations< operations< 4u, Signed >, 1u, Signed >
Chris@102: {
Chris@102: };
Chris@102: 
Chris@102: template< bool Signed >
Chris@102: struct operations< 2u, Signed > :
Chris@102:     public extending_cas_based_operations< operations< 4u, Signed >, 2u, Signed >
Chris@102: {
Chris@102: };
Chris@102: 
Chris@102: BOOST_FORCEINLINE void thread_fence(memory_order order) BOOST_NOEXCEPT
Chris@102: {
Chris@102:     BOOST_ATOMIC_DETAIL_COMPILER_BARRIER();
Chris@102:     if (order == memory_order_seq_cst)
Chris@102:         windows_operations_base::hardware_full_fence();
Chris@102:     BOOST_ATOMIC_DETAIL_COMPILER_BARRIER();
Chris@102: }
Chris@102: 
Chris@102: BOOST_FORCEINLINE void signal_fence(memory_order order) BOOST_NOEXCEPT
Chris@102: {
Chris@102:     if (order != memory_order_relaxed)
Chris@102:         BOOST_ATOMIC_DETAIL_COMPILER_BARRIER();
Chris@102: }
Chris@102: 
Chris@102: } // namespace detail
Chris@102: } // namespace atomics
Chris@102: } // namespace boost
Chris@102: 
Chris@102: #endif // BOOST_ATOMIC_DETAIL_OPS_WINDOWS_HPP_INCLUDED_