64 lines
1.5 KiB
C++
64 lines
1.5 KiB
C++
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// Copyright (c) 2020 Andrey Semashev
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//
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// Distributed under the Boost Software License, Version 1.0.
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// See accompanying file LICENSE_1_0.txt or copy at
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// http://www.boost.org/LICENSE_1_0.txt)
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#ifndef BOOST_ATOMIC_TESTS_ALIGNED_OBJECT_HPP_INCLUDED_
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#define BOOST_ATOMIC_TESTS_ALIGNED_OBJECT_HPP_INCLUDED_
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#include <cstddef>
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#include <new>
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#include <boost/config.hpp>
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#include <boost/cstdint.hpp>
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//! A wrapper that creates an object that has at least the specified alignment
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template< typename T, std::size_t Alignment >
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class aligned_object
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{
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private:
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T* m_p;
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unsigned char m_storage[Alignment + sizeof(T)];
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public:
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aligned_object()
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{
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m_p = new (get_aligned_storage()) T;
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}
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explicit aligned_object(T const& value)
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{
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m_p = new (get_aligned_storage()) T(value);
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}
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~aligned_object() BOOST_NOEXCEPT
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{
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m_p->~T();
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}
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T& get() const BOOST_NOEXCEPT
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{
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return *m_p;
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}
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BOOST_DELETED_FUNCTION(aligned_object(aligned_object const&))
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BOOST_DELETED_FUNCTION(aligned_object& operator= (aligned_object const&))
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private:
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unsigned char* get_aligned_storage()
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{
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#if defined(BOOST_HAS_INTPTR_T)
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typedef boost::uintptr_t uintptr_type;
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#else
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typedef std::size_t uintptr_type;
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#endif
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unsigned char* p = m_storage;
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uintptr_type misalignment = ((uintptr_type)p) & (Alignment - 1u);
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if (misalignment > 0)
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p += Alignment - misalignment;
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return p;
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}
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};
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#endif // BOOST_ATOMIC_TESTS_ALIGNED_OBJECT_HPP_INCLUDED_
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