/* * 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) * * Copyright (c) 2020 Andrey Semashev */ /*! * \file atomic/detail/atomic_ref_template.hpp * * This header contains interface definition of \c atomic_ref template. */ #ifndef BOOST_ATOMIC_DETAIL_ATOMIC_REF_TEMPLATE_HPP_INCLUDED_ #define BOOST_ATOMIC_DETAIL_ATOMIC_REF_TEMPLATE_HPP_INCLUDED_ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if !defined(BOOST_ATOMIC_NO_FLOATING_POINT) #include #include #include #endif #ifdef BOOST_HAS_PRAGMA_ONCE #pragma once #endif #if defined(BOOST_MSVC) #pragma warning(push) // 'boost::atomics::atomic_ref' : multiple assignment operators specified #pragma warning(disable: 4522) #endif /* * IMPLEMENTATION NOTE: All interface functions MUST be declared with BOOST_FORCEINLINE, * see comment for convert_memory_order_to_gcc in ops_gcc_atomic.hpp. */ namespace boost { namespace atomics { namespace detail { template< typename T, bool IsSigned > struct is_atomic_ref_lock_free { typedef T value_type; typedef atomics::detail::operations< sizeof(value_type), IsSigned > operations; typedef typename operations::storage_type storage_type; static BOOST_CONSTEXPR_OR_CONST bool value = sizeof(value_type) == sizeof(storage_type) && operations::is_always_lock_free; }; template< typename T, bool IsSigned > class base_atomic_ref_common { public: typedef T value_type; protected: typedef typename atomics::detail::conditional< atomics::detail::is_atomic_ref_lock_free< T, IsSigned >::value, atomics::detail::operations< sizeof(value_type), IsSigned >, atomics::detail::emulated_operations< sizeof(value_type), atomics::detail::alignment_of< value_type >::value, IsSigned > >::type operations; typedef typename atomics::detail::conditional< sizeof(value_type) <= sizeof(void*), value_type, value_type const& >::type value_arg_type; typedef typename operations::storage_type storage_type; public: static BOOST_CONSTEXPR_OR_CONST std::size_t required_alignment = atomics::detail::alignment_of< value_type >::value <= operations::storage_alignment ? operations::storage_alignment : atomics::detail::alignment_of< value_type >::value; static BOOST_CONSTEXPR_OR_CONST bool is_always_lock_free = operations::is_always_lock_free; protected: value_type* m_value; public: BOOST_FORCEINLINE explicit base_atomic_ref_common(value_type& v) BOOST_NOEXCEPT : m_value(atomics::detail::addressof(v)) { } protected: BOOST_FORCEINLINE storage_type& storage() const BOOST_NOEXCEPT { return *reinterpret_cast< storage_type* >(m_value); } }; #if defined(BOOST_NO_CXX17_INLINE_VARIABLES) template< typename T, bool IsSigned > BOOST_CONSTEXPR_OR_CONST std::size_t base_atomic_ref_common< T, IsSigned >::required_alignment; template< typename T, bool IsSigned > BOOST_CONSTEXPR_OR_CONST bool base_atomic_ref_common< T, IsSigned >::is_always_lock_free; #endif template< typename T, typename Kind > class base_atomic_ref; //! General template. Implementation for user-defined types, such as structs and enums, and pointers to non-object types template< typename T > class base_atomic_ref< T, void > : public base_atomic_ref_common< T, false > { private: typedef base_atomic_ref_common< T, false > base_type; public: typedef typename base_type::value_type value_type; protected: typedef typename base_type::operations operations; typedef typename base_type::storage_type storage_type; typedef typename base_type::value_arg_type value_arg_type; private: typedef atomics::detail::integral_constant< bool, atomics::detail::alignment_of< value_type >::value <= operations::storage_alignment > use_bitwise_cast; public: BOOST_DEFAULTED_FUNCTION(base_atomic_ref(base_atomic_ref const& that) BOOST_ATOMIC_DETAIL_DEF_NOEXCEPT_DECL, BOOST_ATOMIC_DETAIL_DEF_NOEXCEPT_IMPL : base_type(static_cast< base_type const& >(that)) {}) BOOST_FORCEINLINE explicit base_atomic_ref(value_type& v) BOOST_NOEXCEPT : base_type(v) { } BOOST_FORCEINLINE void store(value_arg_type v, memory_order order = memory_order_seq_cst) const BOOST_NOEXCEPT { BOOST_ASSERT(order != memory_order_consume); BOOST_ASSERT(order != memory_order_acquire); BOOST_ASSERT(order != memory_order_acq_rel); operations::store(this->storage(), atomics::detail::bitwise_cast< storage_type >(v), order); } BOOST_FORCEINLINE value_type load(memory_order order = memory_order_seq_cst) const BOOST_NOEXCEPT { BOOST_ASSERT(order != memory_order_release); BOOST_ASSERT(order != memory_order_acq_rel); return atomics::detail::bitwise_cast< value_type >(operations::load(this->storage(), order)); } BOOST_FORCEINLINE value_type exchange(value_arg_type v, memory_order order = memory_order_seq_cst) const BOOST_NOEXCEPT { return atomics::detail::bitwise_cast< value_type >(operations::exchange(this->storage(), atomics::detail::bitwise_cast< storage_type >(v), order)); } BOOST_FORCEINLINE bool compare_exchange_strong(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order) const BOOST_NOEXCEPT { BOOST_ASSERT(failure_order != memory_order_release); BOOST_ASSERT(failure_order != memory_order_acq_rel); BOOST_ASSERT(cas_failure_order_must_not_be_stronger_than_success_order(success_order, failure_order)); return compare_exchange_strong_impl(expected, desired, success_order, failure_order, use_bitwise_cast()); } BOOST_FORCEINLINE bool compare_exchange_strong(value_type& expected, value_arg_type desired, memory_order order = memory_order_seq_cst) const BOOST_NOEXCEPT { return compare_exchange_strong(expected, desired, order, atomics::detail::deduce_failure_order(order)); } BOOST_FORCEINLINE bool compare_exchange_weak(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order) const BOOST_NOEXCEPT { BOOST_ASSERT(failure_order != memory_order_release); BOOST_ASSERT(failure_order != memory_order_acq_rel); BOOST_ASSERT(cas_failure_order_must_not_be_stronger_than_success_order(success_order, failure_order)); return compare_exchange_weak_impl(expected, desired, success_order, failure_order, use_bitwise_cast()); } BOOST_FORCEINLINE bool compare_exchange_weak(value_type& expected, value_arg_type desired, memory_order order = memory_order_seq_cst) const BOOST_NOEXCEPT { return compare_exchange_weak(expected, desired, order, atomics::detail::deduce_failure_order(order)); } BOOST_DELETED_FUNCTION(base_atomic_ref& operator=(base_atomic_ref const&)) private: BOOST_FORCEINLINE bool compare_exchange_strong_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::false_type) const BOOST_NOEXCEPT { #if defined(BOOST_ATOMIC_DETAIL_STORAGE_TYPE_MAY_ALIAS) return operations::compare_exchange_strong(this->storage(), reinterpret_cast< storage_type& >(expected), atomics::detail::bitwise_cast< storage_type >(desired), success_order, failure_order); #else return compare_exchange_strong_impl(expected, desired, success_order, failure_order, atomics::detail::true_type()); #endif } BOOST_FORCEINLINE bool compare_exchange_strong_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::true_type) const BOOST_NOEXCEPT { storage_type old_value = atomics::detail::bitwise_cast< storage_type >(expected); const bool res = operations::compare_exchange_strong(this->storage(), old_value, atomics::detail::bitwise_cast< storage_type >(desired), success_order, failure_order); expected = atomics::detail::bitwise_cast< value_type >(old_value); return res; } BOOST_FORCEINLINE bool compare_exchange_weak_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::false_type) const BOOST_NOEXCEPT { #if defined(BOOST_ATOMIC_DETAIL_STORAGE_TYPE_MAY_ALIAS) return operations::compare_exchange_weak(this->storage(), reinterpret_cast< storage_type& >(expected), atomics::detail::bitwise_cast< storage_type >(desired), success_order, failure_order); #else return compare_exchange_weak_impl(expected, desired, success_order, failure_order, atomics::detail::true_type()); #endif } BOOST_FORCEINLINE bool compare_exchange_weak_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::true_type) const BOOST_NOEXCEPT { storage_type old_value = atomics::detail::bitwise_cast< storage_type >(expected); const bool res = operations::compare_exchange_weak(this->storage(), old_value, atomics::detail::bitwise_cast< storage_type >(desired), success_order, failure_order); expected = atomics::detail::bitwise_cast< value_type >(old_value); return res; } }; //! Implementation for integers template< typename T > class base_atomic_ref< T, int > : public base_atomic_ref_common< T, atomics::detail::is_signed< T >::value > { private: typedef base_atomic_ref_common< T, atomics::detail::is_signed< T >::value > base_type; public: typedef typename base_type::value_type value_type; typedef typename base_type::value_type difference_type; protected: typedef typename base_type::operations operations; typedef atomics::detail::extra_operations< operations, operations::storage_size, operations::is_signed > extra_operations; typedef typename base_type::storage_type storage_type; typedef value_type value_arg_type; private: typedef atomics::detail::integral_constant< bool, atomics::detail::alignment_of< value_type >::value <= operations::storage_alignment > use_bitwise_cast; public: BOOST_DEFAULTED_FUNCTION(base_atomic_ref(base_atomic_ref const& that) BOOST_ATOMIC_DETAIL_DEF_NOEXCEPT_DECL, BOOST_ATOMIC_DETAIL_DEF_NOEXCEPT_IMPL : base_type(static_cast< base_type const& >(that)) {}) BOOST_FORCEINLINE explicit base_atomic_ref(value_type& v) BOOST_NOEXCEPT : base_type(v) { } // Standard methods BOOST_FORCEINLINE void store(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { BOOST_ASSERT(order != memory_order_consume); BOOST_ASSERT(order != memory_order_acquire); BOOST_ASSERT(order != memory_order_acq_rel); operations::store(this->storage(), static_cast< storage_type >(v), order); } BOOST_FORCEINLINE value_type load(memory_order order = memory_order_seq_cst) const BOOST_NOEXCEPT { BOOST_ASSERT(order != memory_order_release); BOOST_ASSERT(order != memory_order_acq_rel); return atomics::detail::integral_truncate< value_type >(operations::load(this->storage(), order)); } BOOST_FORCEINLINE value_type fetch_add(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::integral_truncate< value_type >(operations::fetch_add(this->storage(), static_cast< storage_type >(v), order)); } BOOST_FORCEINLINE value_type fetch_sub(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::integral_truncate< value_type >(operations::fetch_sub(this->storage(), static_cast< storage_type >(v), order)); } BOOST_FORCEINLINE value_type exchange(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::integral_truncate< value_type >(operations::exchange(this->storage(), static_cast< storage_type >(v), order)); } BOOST_FORCEINLINE bool compare_exchange_strong(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order) BOOST_NOEXCEPT { BOOST_ASSERT(failure_order != memory_order_release); BOOST_ASSERT(failure_order != memory_order_acq_rel); BOOST_ASSERT(cas_failure_order_must_not_be_stronger_than_success_order(success_order, failure_order)); return compare_exchange_strong_impl(expected, desired, success_order, failure_order, use_bitwise_cast()); } BOOST_FORCEINLINE bool compare_exchange_strong(value_type& expected, value_arg_type desired, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return compare_exchange_strong(expected, desired, order, atomics::detail::deduce_failure_order(order)); } BOOST_FORCEINLINE bool compare_exchange_weak(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order) BOOST_NOEXCEPT { BOOST_ASSERT(failure_order != memory_order_release); BOOST_ASSERT(failure_order != memory_order_acq_rel); BOOST_ASSERT(cas_failure_order_must_not_be_stronger_than_success_order(success_order, failure_order)); return compare_exchange_weak_impl(expected, desired, success_order, failure_order, use_bitwise_cast()); } BOOST_FORCEINLINE bool compare_exchange_weak(value_type& expected, value_arg_type desired, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return compare_exchange_weak(expected, desired, order, atomics::detail::deduce_failure_order(order)); } BOOST_FORCEINLINE value_type fetch_and(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::integral_truncate< value_type >(operations::fetch_and(this->storage(), static_cast< storage_type >(v), order)); } BOOST_FORCEINLINE value_type fetch_or(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::integral_truncate< value_type >(operations::fetch_or(this->storage(), static_cast< storage_type >(v), order)); } BOOST_FORCEINLINE value_type fetch_xor(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::integral_truncate< value_type >(operations::fetch_xor(this->storage(), static_cast< storage_type >(v), order)); } // Boost.Atomic extensions BOOST_FORCEINLINE value_type fetch_negate(memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::integral_truncate< value_type >(extra_operations::fetch_negate(this->storage(), order)); } BOOST_FORCEINLINE value_type fetch_complement(memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::integral_truncate< value_type >(extra_operations::fetch_complement(this->storage(), order)); } BOOST_FORCEINLINE value_type add(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::integral_truncate< value_type >(extra_operations::add(this->storage(), static_cast< storage_type >(v), order)); } BOOST_FORCEINLINE value_type sub(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::integral_truncate< value_type >(extra_operations::sub(this->storage(), static_cast< storage_type >(v), order)); } BOOST_FORCEINLINE value_type negate(memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::integral_truncate< value_type >(extra_operations::negate(this->storage(), order)); } BOOST_FORCEINLINE value_type bitwise_and(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::integral_truncate< value_type >(extra_operations::bitwise_and(this->storage(), static_cast< storage_type >(v), order)); } BOOST_FORCEINLINE value_type bitwise_or(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::integral_truncate< value_type >(extra_operations::bitwise_or(this->storage(), static_cast< storage_type >(v), order)); } BOOST_FORCEINLINE value_type bitwise_xor(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::integral_truncate< value_type >(extra_operations::bitwise_xor(this->storage(), static_cast< storage_type >(v), order)); } BOOST_FORCEINLINE value_type bitwise_complement(memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::integral_truncate< value_type >(extra_operations::bitwise_complement(this->storage(), order)); } BOOST_FORCEINLINE void opaque_add(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { extra_operations::opaque_add(this->storage(), static_cast< storage_type >(v), order); } BOOST_FORCEINLINE void opaque_sub(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { extra_operations::opaque_sub(this->storage(), static_cast< storage_type >(v), order); } BOOST_FORCEINLINE void opaque_negate(memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { extra_operations::opaque_negate(this->storage(), order); } BOOST_FORCEINLINE void opaque_and(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { extra_operations::opaque_and(this->storage(), static_cast< storage_type >(v), order); } BOOST_FORCEINLINE void opaque_or(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { extra_operations::opaque_or(this->storage(), static_cast< storage_type >(v), order); } BOOST_FORCEINLINE void opaque_xor(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { extra_operations::opaque_xor(this->storage(), static_cast< storage_type >(v), order); } BOOST_FORCEINLINE void opaque_complement(memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { extra_operations::opaque_complement(this->storage(), order); } BOOST_FORCEINLINE bool add_and_test(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return extra_operations::add_and_test(this->storage(), static_cast< storage_type >(v), order); } BOOST_FORCEINLINE bool sub_and_test(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return extra_operations::sub_and_test(this->storage(), static_cast< storage_type >(v), order); } BOOST_FORCEINLINE bool negate_and_test(memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return extra_operations::negate_and_test(this->storage(), order); } BOOST_FORCEINLINE bool and_and_test(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return extra_operations::and_and_test(this->storage(), static_cast< storage_type >(v), order); } BOOST_FORCEINLINE bool or_and_test(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return extra_operations::or_and_test(this->storage(), static_cast< storage_type >(v), order); } BOOST_FORCEINLINE bool xor_and_test(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return extra_operations::xor_and_test(this->storage(), static_cast< storage_type >(v), order); } BOOST_FORCEINLINE bool complement_and_test(memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return extra_operations::complement_and_test(this->storage(), order); } BOOST_FORCEINLINE bool bit_test_and_set(unsigned int bit_number, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { BOOST_ASSERT(bit_number < sizeof(value_type) * 8u); return extra_operations::bit_test_and_set(this->storage(), bit_number, order); } BOOST_FORCEINLINE bool bit_test_and_reset(unsigned int bit_number, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { BOOST_ASSERT(bit_number < sizeof(value_type) * 8u); return extra_operations::bit_test_and_reset(this->storage(), bit_number, order); } BOOST_FORCEINLINE bool bit_test_and_complement(unsigned int bit_number, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { BOOST_ASSERT(bit_number < sizeof(value_type) * 8u); return extra_operations::bit_test_and_complement(this->storage(), bit_number, order); } // Operators BOOST_FORCEINLINE value_type operator++(int) BOOST_NOEXCEPT { return fetch_add(1); } BOOST_FORCEINLINE value_type operator++() BOOST_NOEXCEPT { return add(1); } BOOST_FORCEINLINE value_type operator--(int) BOOST_NOEXCEPT { return fetch_sub(1); } BOOST_FORCEINLINE value_type operator--() BOOST_NOEXCEPT { return sub(1); } BOOST_FORCEINLINE value_type operator+=(difference_type v) BOOST_NOEXCEPT { return add(v); } BOOST_FORCEINLINE value_type operator-=(difference_type v) BOOST_NOEXCEPT { return sub(v); } BOOST_FORCEINLINE value_type operator&=(value_type v) BOOST_NOEXCEPT { return bitwise_and(v); } BOOST_FORCEINLINE value_type operator|=(value_type v) BOOST_NOEXCEPT { return bitwise_or(v); } BOOST_FORCEINLINE value_type operator^=(value_type v) BOOST_NOEXCEPT { return bitwise_xor(v); } BOOST_DELETED_FUNCTION(base_atomic_ref& operator=(base_atomic_ref const&)) private: BOOST_FORCEINLINE bool compare_exchange_strong_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::false_type) const BOOST_NOEXCEPT { #if defined(BOOST_ATOMIC_DETAIL_STORAGE_TYPE_MAY_ALIAS) return operations::compare_exchange_strong(this->storage(), reinterpret_cast< storage_type& >(expected), static_cast< storage_type >(desired), success_order, failure_order); #else return compare_exchange_strong_impl(expected, desired, success_order, failure_order, atomics::detail::true_type()); #endif } BOOST_FORCEINLINE bool compare_exchange_strong_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::true_type) const BOOST_NOEXCEPT { storage_type old_value = static_cast< storage_type >(expected); const bool res = operations::compare_exchange_strong(this->storage(), old_value, static_cast< storage_type >(desired), success_order, failure_order); expected = atomics::detail::integral_truncate< value_type >(old_value); return res; } BOOST_FORCEINLINE bool compare_exchange_weak_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::false_type) const BOOST_NOEXCEPT { #if defined(BOOST_ATOMIC_DETAIL_STORAGE_TYPE_MAY_ALIAS) return operations::compare_exchange_weak(this->storage(), reinterpret_cast< storage_type& >(expected), static_cast< storage_type >(desired), success_order, failure_order); #else return compare_exchange_weak_impl(expected, desired, success_order, failure_order, atomics::detail::true_type()); #endif } BOOST_FORCEINLINE bool compare_exchange_weak_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::true_type) const BOOST_NOEXCEPT { storage_type old_value = static_cast< storage_type >(expected); const bool res = operations::compare_exchange_weak(this->storage(), old_value, static_cast< storage_type >(desired), success_order, failure_order); expected = atomics::detail::integral_truncate< value_type >(old_value); return res; } }; //! Implementation for bool template< > class base_atomic_ref< bool, int > : public base_atomic_ref_common< bool, false > { private: typedef base_atomic_ref_common< bool, false > base_type; public: typedef bool value_type; protected: typedef base_type::operations operations; typedef atomics::detail::extra_operations< operations, operations::storage_size, operations::is_signed > extra_operations; typedef base_type::storage_type storage_type; typedef value_type value_arg_type; private: typedef atomics::detail::integral_constant< bool, atomics::detail::alignment_of< value_type >::value <= operations::storage_alignment > use_bitwise_cast; public: BOOST_DEFAULTED_FUNCTION(base_atomic_ref(base_atomic_ref const& that) BOOST_ATOMIC_DETAIL_DEF_NOEXCEPT_DECL, BOOST_ATOMIC_DETAIL_DEF_NOEXCEPT_IMPL : base_type(static_cast< base_type const& >(that)) {}) BOOST_FORCEINLINE explicit base_atomic_ref(value_type& v) BOOST_NOEXCEPT : base_type(v) { } // Standard methods BOOST_FORCEINLINE void store(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { BOOST_ASSERT(order != memory_order_consume); BOOST_ASSERT(order != memory_order_acquire); BOOST_ASSERT(order != memory_order_acq_rel); operations::store(this->storage(), static_cast< storage_type >(v), order); } BOOST_FORCEINLINE value_type load(memory_order order = memory_order_seq_cst) const BOOST_NOEXCEPT { BOOST_ASSERT(order != memory_order_release); BOOST_ASSERT(order != memory_order_acq_rel); return !!operations::load(this->storage(), order); } BOOST_FORCEINLINE value_type exchange(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return !!operations::exchange(this->storage(), static_cast< storage_type >(v), order); } BOOST_FORCEINLINE bool compare_exchange_strong(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order) BOOST_NOEXCEPT { BOOST_ASSERT(failure_order != memory_order_release); BOOST_ASSERT(failure_order != memory_order_acq_rel); BOOST_ASSERT(cas_failure_order_must_not_be_stronger_than_success_order(success_order, failure_order)); return compare_exchange_strong_impl(expected, desired, success_order, failure_order, use_bitwise_cast()); } BOOST_FORCEINLINE bool compare_exchange_strong(value_type& expected, value_arg_type desired, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return compare_exchange_strong(expected, desired, order, atomics::detail::deduce_failure_order(order)); } BOOST_FORCEINLINE bool compare_exchange_weak(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order) BOOST_NOEXCEPT { BOOST_ASSERT(failure_order != memory_order_release); BOOST_ASSERT(failure_order != memory_order_acq_rel); BOOST_ASSERT(cas_failure_order_must_not_be_stronger_than_success_order(success_order, failure_order)); return compare_exchange_weak_impl(expected, desired, success_order, failure_order, use_bitwise_cast()); } BOOST_FORCEINLINE bool compare_exchange_weak(value_type& expected, value_arg_type desired, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return compare_exchange_weak(expected, desired, order, atomics::detail::deduce_failure_order(order)); } BOOST_DELETED_FUNCTION(base_atomic_ref& operator=(base_atomic_ref const&)) private: BOOST_FORCEINLINE bool compare_exchange_strong_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::false_type) const BOOST_NOEXCEPT { #if defined(BOOST_ATOMIC_DETAIL_STORAGE_TYPE_MAY_ALIAS) return operations::compare_exchange_strong(this->storage(), reinterpret_cast< storage_type& >(expected), static_cast< storage_type >(desired), success_order, failure_order); #else return compare_exchange_strong_impl(expected, desired, success_order, failure_order, atomics::detail::true_type()); #endif } BOOST_FORCEINLINE bool compare_exchange_strong_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::true_type) const BOOST_NOEXCEPT { storage_type old_value = static_cast< storage_type >(expected); const bool res = operations::compare_exchange_strong(this->storage(), old_value, static_cast< storage_type >(desired), success_order, failure_order); expected = !!old_value; return res; } BOOST_FORCEINLINE bool compare_exchange_weak_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::false_type) const BOOST_NOEXCEPT { #if defined(BOOST_ATOMIC_DETAIL_STORAGE_TYPE_MAY_ALIAS) return operations::compare_exchange_weak(this->storage(), reinterpret_cast< storage_type& >(expected), static_cast< storage_type >(desired), success_order, failure_order); #else return compare_exchange_weak_impl(expected, desired, success_order, failure_order, atomics::detail::true_type()); #endif } BOOST_FORCEINLINE bool compare_exchange_weak_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::true_type) const BOOST_NOEXCEPT { storage_type old_value = static_cast< storage_type >(expected); const bool res = operations::compare_exchange_weak(this->storage(), old_value, static_cast< storage_type >(desired), success_order, failure_order); expected = !!old_value; return res; } }; #if !defined(BOOST_ATOMIC_NO_FLOATING_POINT) //! Implementation for floating point types template< typename T > class base_atomic_ref< T, float > : public base_atomic_ref_common< T, false > { private: typedef base_atomic_ref_common< T, false > base_type; public: typedef typename base_type::value_type value_type; typedef typename base_type::value_type difference_type; protected: typedef typename base_type::operations operations; typedef atomics::detail::extra_operations< operations, operations::storage_size, operations::is_signed > extra_operations; typedef atomics::detail::fp_operations< extra_operations, value_type, operations::storage_size > fp_operations; typedef atomics::detail::extra_fp_operations< fp_operations, value_type, operations::storage_size > extra_fp_operations; typedef typename base_type::storage_type storage_type; typedef value_type value_arg_type; private: typedef atomics::detail::integral_constant< bool, atomics::detail::value_sizeof< value_type >::value != sizeof(storage_type) > has_padding_bits; typedef atomics::detail::integral_constant< bool, has_padding_bits::value || atomics::detail::alignment_of< value_type >::value <= operations::storage_alignment > use_bitwise_cast; public: BOOST_DEFAULTED_FUNCTION(base_atomic_ref(base_atomic_ref const& that) BOOST_ATOMIC_DETAIL_DEF_NOEXCEPT_DECL, BOOST_ATOMIC_DETAIL_DEF_NOEXCEPT_IMPL : base_type(static_cast< base_type const& >(that)) {}) BOOST_FORCEINLINE explicit base_atomic_ref(value_type& v) BOOST_NOEXCEPT : base_type(v) { this->clear_padding_bits(has_padding_bits()); } BOOST_FORCEINLINE void store(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { BOOST_ASSERT(order != memory_order_consume); BOOST_ASSERT(order != memory_order_acquire); BOOST_ASSERT(order != memory_order_acq_rel); operations::store(this->storage(), atomics::detail::bitwise_fp_cast< storage_type >(v), order); } BOOST_FORCEINLINE value_type load(memory_order order = memory_order_seq_cst) const BOOST_NOEXCEPT { BOOST_ASSERT(order != memory_order_release); BOOST_ASSERT(order != memory_order_acq_rel); return atomics::detail::bitwise_fp_cast< value_type >(operations::load(this->storage(), order)); } BOOST_FORCEINLINE value_type fetch_add(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return fp_operations::fetch_add(this->storage(), v, order); } BOOST_FORCEINLINE value_type fetch_sub(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return fp_operations::fetch_sub(this->storage(), v, order); } BOOST_FORCEINLINE value_type exchange(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::bitwise_fp_cast< value_type >(operations::exchange(this->storage(), atomics::detail::bitwise_fp_cast< storage_type >(v), order)); } BOOST_FORCEINLINE bool compare_exchange_strong(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order) BOOST_NOEXCEPT { BOOST_ASSERT(failure_order != memory_order_release); BOOST_ASSERT(failure_order != memory_order_acq_rel); BOOST_ASSERT(cas_failure_order_must_not_be_stronger_than_success_order(success_order, failure_order)); return compare_exchange_strong_impl(expected, desired, success_order, failure_order, use_bitwise_cast()); } BOOST_FORCEINLINE bool compare_exchange_strong(value_type& expected, value_arg_type desired, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return compare_exchange_strong(expected, desired, order, atomics::detail::deduce_failure_order(order)); } BOOST_FORCEINLINE bool compare_exchange_weak(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order) BOOST_NOEXCEPT { BOOST_ASSERT(failure_order != memory_order_release); BOOST_ASSERT(failure_order != memory_order_acq_rel); BOOST_ASSERT(cas_failure_order_must_not_be_stronger_than_success_order(success_order, failure_order)); return compare_exchange_weak_impl(expected, desired, success_order, failure_order, use_bitwise_cast()); } BOOST_FORCEINLINE bool compare_exchange_weak(value_type& expected, value_arg_type desired, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return compare_exchange_weak(expected, desired, order, atomics::detail::deduce_failure_order(order)); } // Boost.Atomic extensions BOOST_FORCEINLINE value_type fetch_negate(memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return extra_fp_operations::fetch_negate(this->storage(), order); } BOOST_FORCEINLINE value_type add(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return extra_fp_operations::add(this->storage(), v, order); } BOOST_FORCEINLINE value_type sub(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return extra_fp_operations::sub(this->storage(), v, order); } BOOST_FORCEINLINE value_type negate(memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return extra_fp_operations::negate(this->storage(), order); } BOOST_FORCEINLINE void opaque_add(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { extra_fp_operations::opaque_add(this->storage(), v, order); } BOOST_FORCEINLINE void opaque_sub(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { extra_fp_operations::opaque_sub(this->storage(), v, order); } BOOST_FORCEINLINE void opaque_negate(memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { extra_fp_operations::opaque_negate(this->storage(), order); } // Operators BOOST_FORCEINLINE value_type operator+=(difference_type v) BOOST_NOEXCEPT { return add(v); } BOOST_FORCEINLINE value_type operator-=(difference_type v) BOOST_NOEXCEPT { return sub(v); } BOOST_DELETED_FUNCTION(base_atomic_ref& operator=(base_atomic_ref const&)) private: BOOST_FORCEINLINE void clear_padding_bits(atomics::detail::false_type) const BOOST_NOEXCEPT { } BOOST_FORCEINLINE void clear_padding_bits(atomics::detail::true_type) const BOOST_NOEXCEPT { storage_type old_value = operations::load(this->storage(), boost::memory_order_relaxed); while (true) { storage_type new_value = old_value; atomics::detail::clear_tail_padding_bits< atomics::detail::value_sizeof< value_type >::value >(new_value); bool res = operations::compare_exchange_weak(this->storage(), old_value, new_value, boost::memory_order_relaxed, boost::memory_order_relaxed); if (BOOST_LIKELY(res)) break; } } BOOST_FORCEINLINE bool compare_exchange_strong_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::false_type) const BOOST_NOEXCEPT { #if defined(BOOST_ATOMIC_DETAIL_STORAGE_TYPE_MAY_ALIAS) return operations::compare_exchange_strong(this->storage(), reinterpret_cast< storage_type& >(expected), atomics::detail::bitwise_fp_cast< storage_type >(desired), success_order, failure_order); #else return compare_exchange_strong_impl(expected, desired, success_order, failure_order, atomics::detail::true_type()); #endif } BOOST_FORCEINLINE bool compare_exchange_strong_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::true_type) const BOOST_NOEXCEPT { storage_type old_value = atomics::detail::bitwise_fp_cast< storage_type >(expected); const bool res = operations::compare_exchange_strong(this->storage(), old_value, atomics::detail::bitwise_fp_cast< storage_type >(desired), success_order, failure_order); expected = atomics::detail::bitwise_fp_cast< value_type >(old_value); return res; } BOOST_FORCEINLINE bool compare_exchange_weak_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::false_type) const BOOST_NOEXCEPT { #if defined(BOOST_ATOMIC_DETAIL_STORAGE_TYPE_MAY_ALIAS) return operations::compare_exchange_weak(this->storage(), reinterpret_cast< storage_type& >(expected), atomics::detail::bitwise_fp_cast< storage_type >(desired), success_order, failure_order); #else return compare_exchange_weak_impl(expected, desired, success_order, failure_order, atomics::detail::true_type()); #endif } BOOST_FORCEINLINE bool compare_exchange_weak_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::true_type) const BOOST_NOEXCEPT { storage_type old_value = atomics::detail::bitwise_fp_cast< storage_type >(expected); const bool res = operations::compare_exchange_weak(this->storage(), old_value, atomics::detail::bitwise_fp_cast< storage_type >(desired), success_order, failure_order); expected = atomics::detail::bitwise_fp_cast< value_type >(old_value); return res; } }; #endif // !defined(BOOST_ATOMIC_NO_FLOATING_POINT) //! Implementation for pointers to object types template< typename T > class base_atomic_ref< T*, void* > : public base_atomic_ref_common< T*, false > { private: typedef base_atomic_ref_common< T*, false > base_type; public: typedef typename base_type::value_type value_type; typedef std::ptrdiff_t difference_type; protected: typedef typename base_type::operations operations; typedef atomics::detail::extra_operations< operations, operations::storage_size, operations::is_signed > extra_operations; typedef typename base_type::storage_type storage_type; typedef value_type value_arg_type; private: typedef atomics::detail::integral_constant< bool, atomics::detail::alignment_of< value_type >::value <= operations::storage_alignment > use_bitwise_cast; // uintptr_storage_type is the minimal storage type that is enough to store pointers. The actual storage_type theoretically may be larger, // if the target architecture only supports atomic ops on larger data. Typically, though, they are the same type. typedef atomics::detail::uintptr_t uintptr_storage_type; public: BOOST_DEFAULTED_FUNCTION(base_atomic_ref(base_atomic_ref const& that) BOOST_ATOMIC_DETAIL_DEF_NOEXCEPT_DECL, BOOST_ATOMIC_DETAIL_DEF_NOEXCEPT_IMPL : base_type(static_cast< base_type const& >(that)) {}) BOOST_FORCEINLINE explicit base_atomic_ref(value_type& v) BOOST_NOEXCEPT : base_type(v) { } // Standard methods BOOST_FORCEINLINE void store(value_arg_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { BOOST_ASSERT(order != memory_order_consume); BOOST_ASSERT(order != memory_order_acquire); BOOST_ASSERT(order != memory_order_acq_rel); operations::store(this->storage(), atomics::detail::bitwise_cast< uintptr_storage_type >(v), order); } BOOST_FORCEINLINE value_type load(memory_order order = memory_order_seq_cst) const BOOST_NOEXCEPT { BOOST_ASSERT(order != memory_order_release); BOOST_ASSERT(order != memory_order_acq_rel); return atomics::detail::bitwise_cast< value_type >(static_cast< uintptr_storage_type >(operations::load(this->storage(), order))); } BOOST_FORCEINLINE value_type fetch_add(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::bitwise_cast< value_type >(static_cast< uintptr_storage_type >(operations::fetch_add(this->storage(), static_cast< uintptr_storage_type >(v * sizeof(T)), order))); } BOOST_FORCEINLINE value_type fetch_sub(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::bitwise_cast< value_type >(static_cast< uintptr_storage_type >(operations::fetch_sub(this->storage(), static_cast< uintptr_storage_type >(v * sizeof(T)), order))); } BOOST_FORCEINLINE value_type exchange(value_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::bitwise_cast< value_type >(static_cast< uintptr_storage_type >(operations::exchange(this->storage(), atomics::detail::bitwise_cast< uintptr_storage_type >(v), order))); } BOOST_FORCEINLINE bool compare_exchange_strong(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order) BOOST_NOEXCEPT { BOOST_ASSERT(failure_order != memory_order_release); BOOST_ASSERT(failure_order != memory_order_acq_rel); BOOST_ASSERT(cas_failure_order_must_not_be_stronger_than_success_order(success_order, failure_order)); return compare_exchange_strong_impl(expected, desired, success_order, failure_order, use_bitwise_cast()); } BOOST_FORCEINLINE bool compare_exchange_strong(value_type& expected, value_arg_type desired, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return compare_exchange_strong(expected, desired, order, atomics::detail::deduce_failure_order(order)); } BOOST_FORCEINLINE bool compare_exchange_weak(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order) BOOST_NOEXCEPT { BOOST_ASSERT(failure_order != memory_order_release); BOOST_ASSERT(failure_order != memory_order_acq_rel); BOOST_ASSERT(cas_failure_order_must_not_be_stronger_than_success_order(success_order, failure_order)); return compare_exchange_weak_impl(expected, desired, success_order, failure_order, use_bitwise_cast()); } BOOST_FORCEINLINE bool compare_exchange_weak(value_type& expected, value_arg_type desired, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return compare_exchange_weak(expected, desired, order, atomics::detail::deduce_failure_order(order)); } // Boost.Atomic extensions BOOST_FORCEINLINE value_type add(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::bitwise_cast< value_type >(static_cast< uintptr_storage_type >(extra_operations::add(this->storage(), static_cast< uintptr_storage_type >(v * sizeof(T)), order))); } BOOST_FORCEINLINE value_type sub(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return atomics::detail::bitwise_cast< value_type >(static_cast< uintptr_storage_type >(extra_operations::sub(this->storage(), static_cast< uintptr_storage_type >(v * sizeof(T)), order))); } BOOST_FORCEINLINE void opaque_add(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { extra_operations::opaque_add(this->storage(), static_cast< uintptr_storage_type >(v * sizeof(T)), order); } BOOST_FORCEINLINE void opaque_sub(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { extra_operations::opaque_sub(this->storage(), static_cast< uintptr_storage_type >(v * sizeof(T)), order); } BOOST_FORCEINLINE bool add_and_test(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return extra_operations::add_and_test(this->storage(), static_cast< uintptr_storage_type >(v * sizeof(T)), order); } BOOST_FORCEINLINE bool sub_and_test(difference_type v, memory_order order = memory_order_seq_cst) BOOST_NOEXCEPT { return extra_operations::sub_and_test(this->storage(), static_cast< uintptr_storage_type >(v * sizeof(T)), order); } // Operators BOOST_FORCEINLINE value_type operator++(int) BOOST_NOEXCEPT { return fetch_add(1); } BOOST_FORCEINLINE value_type operator++() BOOST_NOEXCEPT { return add(1); } BOOST_FORCEINLINE value_type operator--(int) BOOST_NOEXCEPT { return fetch_sub(1); } BOOST_FORCEINLINE value_type operator--() BOOST_NOEXCEPT { return sub(1); } BOOST_FORCEINLINE value_type operator+=(difference_type v) BOOST_NOEXCEPT { return add(v); } BOOST_FORCEINLINE value_type operator-=(difference_type v) BOOST_NOEXCEPT { return sub(v); } BOOST_DELETED_FUNCTION(base_atomic_ref& operator=(base_atomic_ref const&)) private: BOOST_FORCEINLINE bool compare_exchange_strong_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::false_type) const BOOST_NOEXCEPT { #if defined(BOOST_ATOMIC_DETAIL_STORAGE_TYPE_MAY_ALIAS) return operations::compare_exchange_strong(this->storage(), reinterpret_cast< storage_type& >(expected), atomics::detail::bitwise_cast< uintptr_storage_type >(desired), success_order, failure_order); #else return compare_exchange_strong_impl(expected, desired, success_order, failure_order, atomics::detail::true_type()); #endif } BOOST_FORCEINLINE bool compare_exchange_strong_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::true_type) const BOOST_NOEXCEPT { storage_type old_value = atomics::detail::bitwise_cast< uintptr_storage_type >(expected); const bool res = operations::compare_exchange_strong(this->storage(), old_value, atomics::detail::bitwise_cast< uintptr_storage_type >(desired), success_order, failure_order); expected = atomics::detail::bitwise_cast< value_type >(static_cast< uintptr_storage_type >(old_value)); return res; } BOOST_FORCEINLINE bool compare_exchange_weak_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::false_type) const BOOST_NOEXCEPT { #if defined(BOOST_ATOMIC_DETAIL_STORAGE_TYPE_MAY_ALIAS) return operations::compare_exchange_weak(this->storage(), reinterpret_cast< storage_type& >(expected), atomics::detail::bitwise_cast< uintptr_storage_type >(desired), success_order, failure_order); #else return compare_exchange_weak_impl(expected, desired, success_order, failure_order, atomics::detail::true_type()); #endif } BOOST_FORCEINLINE bool compare_exchange_weak_impl(value_type& expected, value_arg_type desired, memory_order success_order, memory_order failure_order, atomics::detail::true_type) const BOOST_NOEXCEPT { storage_type old_value = atomics::detail::bitwise_cast< uintptr_storage_type >(expected); const bool res = operations::compare_exchange_weak(this->storage(), old_value, atomics::detail::bitwise_cast< uintptr_storage_type >(desired), success_order, failure_order); expected = atomics::detail::bitwise_cast< value_type >(static_cast< uintptr_storage_type >(old_value)); return res; } }; } // namespace detail template< typename T > class atomic_ref : public atomics::detail::base_atomic_ref< T, typename atomics::detail::classify< T >::type > { private: typedef atomics::detail::base_atomic_ref< T, typename atomics::detail::classify< T >::type > base_type; typedef typename base_type::value_arg_type value_arg_type; public: typedef typename base_type::value_type value_type; BOOST_STATIC_ASSERT_MSG(sizeof(value_type) > 0u, "boost::atomic_ref requires T to be a complete type"); #if !defined(BOOST_ATOMIC_DETAIL_NO_CXX11_IS_TRIVIALLY_COPYABLE) BOOST_STATIC_ASSERT_MSG(atomics::detail::is_trivially_copyable< value_type >::value, "boost::atomic_ref requires T to be a trivially copyable type"); #endif private: typedef typename base_type::storage_type storage_type; public: BOOST_DEFAULTED_FUNCTION(atomic_ref(atomic_ref const& that) BOOST_ATOMIC_DETAIL_DEF_NOEXCEPT_DECL, BOOST_ATOMIC_DETAIL_DEF_NOEXCEPT_IMPL : base_type(static_cast< base_type const& >(that)) {}) BOOST_FORCEINLINE explicit atomic_ref(value_type& v) BOOST_NOEXCEPT : base_type(v) { // Check that referenced object alignment satisfies required alignment BOOST_ASSERT((((atomics::detail::uintptr_t)this->m_value) & (base_type::required_alignment - 1u)) == 0u); } BOOST_FORCEINLINE value_type operator= (value_arg_type v) BOOST_NOEXCEPT { this->store(v); return v; } BOOST_FORCEINLINE operator value_type() const BOOST_NOEXCEPT { return this->load(); } BOOST_FORCEINLINE bool is_lock_free() const BOOST_NOEXCEPT { // C++20 specifies that is_lock_free returns true if operations on *all* objects of the atomic_ref type are lock-free. // This does not allow to return true or false depending on the referenced object runtime alignment. Currently, Boost.Atomic // follows this specification, although we may support runtime alignment checking in the future. return base_type::is_always_lock_free; } BOOST_FORCEINLINE value_type& value() const BOOST_NOEXCEPT { return *this->m_value; } BOOST_DELETED_FUNCTION(atomic_ref& operator= (atomic_ref const&)) }; } // namespace atomics } // namespace boost #if defined(BOOST_MSVC) #pragma warning(pop) #endif #endif // BOOST_ATOMIC_DETAIL_ATOMIC_REF_TEMPLATE_HPP_INCLUDED_