You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
69 lines
2.3 KiB
C++
69 lines
2.3 KiB
C++
/*
|
|
* 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) 2014 Andrey Semashev
|
|
*/
|
|
/*!
|
|
* \file atomic/detail/ops_extending_cas_based.hpp
|
|
*
|
|
* This header contains a boilerplate of the \c operations template implementation that requires sign/zero extension in arithmetic operations.
|
|
*/
|
|
|
|
#ifndef BOOST_ATOMIC_DETAIL_OPS_EXTENDING_CAS_BASED_HPP_INCLUDED_
|
|
#define BOOST_ATOMIC_DETAIL_OPS_EXTENDING_CAS_BASED_HPP_INCLUDED_
|
|
|
|
#include <cstddef>
|
|
#include <boost/memory_order.hpp>
|
|
#include <boost/atomic/detail/config.hpp>
|
|
#include <boost/atomic/detail/storage_type.hpp>
|
|
|
|
#ifdef BOOST_HAS_PRAGMA_ONCE
|
|
#pragma once
|
|
#endif
|
|
|
|
namespace boost {
|
|
namespace atomics {
|
|
namespace detail {
|
|
|
|
template< typename Base, std::size_t Size, bool Signed >
|
|
struct extending_cas_based_operations :
|
|
public Base
|
|
{
|
|
typedef typename Base::storage_type storage_type;
|
|
typedef typename make_storage_type< Size, Signed >::type emulated_storage_type;
|
|
|
|
static BOOST_FORCEINLINE storage_type fetch_add(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT
|
|
{
|
|
storage_type old_val;
|
|
atomics::detail::non_atomic_load(storage, old_val);
|
|
emulated_storage_type new_val;
|
|
do
|
|
{
|
|
new_val = static_cast< emulated_storage_type >(old_val) + static_cast< emulated_storage_type >(v);
|
|
}
|
|
while (!Base::compare_exchange_weak(storage, old_val, static_cast< storage_type >(new_val), order, memory_order_relaxed));
|
|
return old_val;
|
|
}
|
|
|
|
static BOOST_FORCEINLINE storage_type fetch_sub(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT
|
|
{
|
|
storage_type old_val;
|
|
atomics::detail::non_atomic_load(storage, old_val);
|
|
emulated_storage_type new_val;
|
|
do
|
|
{
|
|
new_val = static_cast< emulated_storage_type >(old_val) - static_cast< emulated_storage_type >(v);
|
|
}
|
|
while (!Base::compare_exchange_weak(storage, old_val, static_cast< storage_type >(new_val), order, memory_order_relaxed));
|
|
return old_val;
|
|
}
|
|
};
|
|
|
|
} // namespace detail
|
|
} // namespace atomics
|
|
} // namespace boost
|
|
|
|
#endif // BOOST_ATOMIC_DETAIL_OPS_EXTENDING_CAS_BASED_HPP_INCLUDED_
|