ceph/src/boost/boost/atomic/detail/extra_fp_ops_emulated.hpp

   1 /*
   2  * Distributed under the Boost Software License, Version 1.0.
   3  * (See accompanying file LICENSE_1_0.txt or copy at
   4  * http://www.boost.org/LICENSE_1_0.txt)
   5  *
   6  * Copyright (c) 2018 Andrey Semashev
   7  */
   8 /*!
   9  * \file   atomic/detail/extra_fp_ops_emulated.hpp
  10  *
  11  * This header contains emulated (lock-based) implementation of the extra floating point atomic operations.
  12  */
  13
  14 #ifndef BOOST_ATOMIC_DETAIL_EXTRA_FP_OPS_EMULATED_HPP_INCLUDED_
  15 #define BOOST_ATOMIC_DETAIL_EXTRA_FP_OPS_EMULATED_HPP_INCLUDED_
  16
  17 #include <cstddef>
  18 #include <boost/memory_order.hpp>
  19 #include <boost/atomic/detail/config.hpp>
  20 #include <boost/atomic/detail/bitwise_fp_cast.hpp>
  21 #include <boost/atomic/detail/extra_fp_operations_fwd.hpp>
  22 #include <boost/atomic/detail/lockpool.hpp>
  23
  24 #ifdef BOOST_HAS_PRAGMA_ONCE
  25 #pragma once
  26 #endif
  27
  28 namespace boost {
  29 namespace atomics {
  30 namespace detail {
  31
  32 //! Generic implementation of extra floating point operations
  33 template< typename Base, typename Value, std::size_t Size >
  34 struct emulated_extra_fp_operations :
  35     public Base
  36 {
  37     typedef Base base_type;
  38     typedef typename base_type::storage_type storage_type;
  39     typedef Value value_type;
  40
  41     static BOOST_FORCEINLINE value_type fetch_negate(storage_type volatile& storage, memory_order) BOOST_NOEXCEPT
  42     {
  43         storage_type& s = const_cast< storage_type& >(storage);
  44         lockpool::scoped_lock lock(&storage);
  45         value_type old_val = atomics::detail::bitwise_fp_cast< value_type >(s);
  46         value_type new_val = -old_val;
  47         s = atomics::detail::bitwise_fp_cast< storage_type >(new_val);
  48         return old_val;
  49     }
  50
  51     static BOOST_FORCEINLINE value_type negate(storage_type volatile& storage, memory_order) BOOST_NOEXCEPT
  52     {
  53         storage_type& s = const_cast< storage_type& >(storage);
  54         lockpool::scoped_lock lock(&storage);
  55         value_type old_val = atomics::detail::bitwise_fp_cast< value_type >(s);
  56         value_type new_val = -old_val;
  57         s = atomics::detail::bitwise_fp_cast< storage_type >(new_val);
  58         return new_val;
  59     }
  60
  61     static BOOST_FORCEINLINE value_type add(storage_type volatile& storage, value_type v, memory_order) BOOST_NOEXCEPT
  62     {
  63         storage_type& s = const_cast< storage_type& >(storage);
  64         lockpool::scoped_lock lock(&storage);
  65         value_type old_val = atomics::detail::bitwise_fp_cast< value_type >(s);
  66         value_type new_val = old_val + v;
  67         s = atomics::detail::bitwise_fp_cast< storage_type >(new_val);
  68         return new_val;
  69     }
  70
  71     static BOOST_FORCEINLINE value_type sub(storage_type volatile& storage, value_type v, memory_order) BOOST_NOEXCEPT
  72     {
  73         storage_type& s = const_cast< storage_type& >(storage);
  74         lockpool::scoped_lock lock(&storage);
  75         value_type old_val = atomics::detail::bitwise_fp_cast< value_type >(s);
  76         value_type new_val = old_val - v;
  77         s = atomics::detail::bitwise_fp_cast< storage_type >(new_val);
  78         return new_val;
  79     }
  80
  81     static BOOST_FORCEINLINE void opaque_negate(storage_type volatile& storage, memory_order order) BOOST_NOEXCEPT
  82     {
  83         fetch_negate(storage, order);
  84     }
  85
  86     static BOOST_FORCEINLINE void opaque_add(storage_type volatile& storage, value_type v, memory_order order) BOOST_NOEXCEPT
  87     {
  88         base_type::fetch_add(storage, v, order);
  89     }
  90
  91     static BOOST_FORCEINLINE void opaque_sub(storage_type volatile& storage, value_type v, memory_order order) BOOST_NOEXCEPT
  92     {
  93         base_type::fetch_sub(storage, v, order);
  94     }
  95 };
  96
  97 template< typename Base, typename Value, std::size_t Size >
  98 struct extra_fp_operations< Base, Value, Size, false > :
  99     public emulated_extra_fp_operations< Base, Value, Size >
 100 {
 101 };
 102
 103 } // namespace detail
 104 } // namespace atomics
 105 } // namespace boost
 106
 107 #endif // BOOST_ATOMIC_DETAIL_EXTRA_FP_OPS_EMULATED_HPP_INCLUDED_