G4atomic_defines.hh

Go to the documentation of this file.

//
// ********************************************************************
// * License and Disclaimer                                           *
// *                                                                  *
// * The  Geant4 software  is  copyright of the Copyright Holders  of *
// * the Geant4 Collaboration.  It is provided  under  the terms  and *
// * conditions of the Geant4 Software License,  included in the file *
// * LICENSE and available at  http://cern.ch/geant4/license .  These *
// * include a list of copyright holders.                             *
// *                                                                  *
// * Neither the authors of this software system, nor their employing *
// * institutes,nor the agencies providing financial support for this *
// * work  make  any representation or  warranty, express or implied, *
// * regarding  this  software system or assume any liability for its *
// * use.  Please see the license in the file  LICENSE  and URL above *
// * for the full disclaimer and the limitation of liability.         *
// *                                                                  *
// * This  code  implementation is the result of  the  scientific and *
// * technical work of the GEANT4 collaboration.                      *
// * By using,  copying,  modifying or  distributing the software (or *
// * any work based  on the software)  you  agree  to acknowledge its *
// * use  in  resulting  scientific  publications,  and indicate your *
// * acceptance of all terms of the Geant4 Software license.          *
// ********************************************************************
//
/// \file parallel/ThreadsafeScorers/include/G4atomic_defines.hh
/// \brief Definition of the G4atomic_defines class
//
//
//
//
/// This is a functional class for G4atomic. The functions in this
///     file are not intended to be used outside of their implementation
///     in G4atomic.
//
//
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
 
#ifndef G4atomic_defines_hh_
#define G4atomic_defines_hh_
 
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
 
#ifdef G4MULTITHREADED
 
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
 
#  include <functional>
#  include <atomic>
 
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
 
namespace atomics
{
  //------------------------------------------------------------------------//
  namespace details
  {
    //--------------------------------------------------------------------//
    template <typename _Tp>
    using OpFunction = std::function<_Tp(const _Tp&, const _Tp&)>;
    //--------------------------------------------------------------------//
    template <typename _Tp>
    inline void do_fetch_and_store(std::atomic<_Tp>* _atomic, const _Tp& _value,
                                   std::memory_order mem_odr)
    {
      _atomic->store(_value, mem_odr);
    }
    //--------------------------------------------------------------------//
    template <typename _Tp>
    inline void do_fetch_and_store(std::atomic<_Tp>* _atomic,
                                   const std::atomic<_Tp>& _value,
                                   std::memory_order mem_odr)
    {
      _atomic->store(_value.load(), mem_odr);
    }
    //--------------------------------------------------------------------//
    template <typename _Tp>
    inline void do_compare_and_swap(std::atomic<_Tp>* _atomic,
                                    const _Tp& _value,
                                    const OpFunction<_Tp>& _operator,
                                    std::memory_order mem_odr)
    {
      _Tp _expected = _Tp();
      do
      {
        _expected = _atomic->load();
      } while(!(_atomic->compare_exchange_weak(
        _expected, _operator(_expected, _value), mem_odr)));
    }
    //--------------------------------------------------------------------//
    template <typename _Tp>
    inline void do_compare_and_swap(std::atomic<_Tp>* _atomic,
                                    const std::atomic<_Tp>& _atomic_value,
                                    const OpFunction<_Tp>& _operator,
                                    std::memory_order mem_odr)
    {
      _Tp _expected = _Tp();
      do
      {
        _expected = _atomic->load();
      } while(!(_atomic->compare_exchange_weak(
        _expected, _operator(_expected, _atomic_value.load()), mem_odr)));
    }
    //--------------------------------------------------------------------//
  }  // namespace details
  //------------------------------------------------------------------------//
  //  WITH ATOMIC TEMPLATE BASE TYPE AS SECOND PARAMETER
  //------------------------------------------------------------------------//
  template <typename T>
  inline void set(std::atomic<T>* _atomic, const T& _desired,
                  std::memory_order mem_odr = std::memory_order_seq_cst)
  {
    details::do_compare_and_swap(
      _atomic, _desired,
      details::OpFunction<T>([](const T&, const T& y) { return y; }), mem_odr);
  }
  //------------------------------------------------------------------------//
  template <typename T>
  inline void set(std::atomic<T>& _atomic, const T& _desired,
                  std::memory_order mem_odr = std::memory_order_seq_cst)
  {
    set(&_atomic, _desired, mem_odr);
  }
  //------------------------------------------------------------------------//
  template <typename T>
  inline void increment(std::atomic<T>* _atomic, const T& _increment,
                        std::memory_order mem_odr)
  {
    details::do_compare_and_swap(
      _atomic, _increment,
      details::OpFunction<T>([](const T& x, const T& y) { return x + y; }),
      mem_odr);
  }
  //------------------------------------------------------------------------//
  template <typename T>
  inline void decrement(std::atomic<T>* _atomic, const T& _decrement,
                        std::memory_order mem_odr)
  {
    details::do_compare_and_swap(
      _atomic, _decrement,
      details::OpFunction<T>([](const T& x, const T& y) { return x - y; }),
      mem_odr);
  }
  //------------------------------------------------------------------------//
  template <typename T>
  inline void multiply(std::atomic<T>* _atomic, const T& _factor,
                       std::memory_order mem_odr)
  {
    details::do_compare_and_swap(
      _atomic, _factor,
      details::OpFunction<T>([](const T& x, const T& y) { return x * y; }),
      mem_odr);
  }
  //------------------------------------------------------------------------//
  template <typename T>
  inline void divide(std::atomic<T>* _atomic, const T& _factor,
                     std::memory_order mem_odr)
  {
    details::do_compare_and_swap(
      _atomic, _factor,
      details::OpFunction<T>([](const T& x, const T& y) { return x / y; }),
      mem_odr);
  }
  //------------------------------------------------------------------------//
  //  WITH ATOMICS AS SECOND PARAMETER
  //------------------------------------------------------------------------//
  template <typename T>
  inline void set(std::atomic<T>* _atomic,
                  const std::atomic<T>& _atomic_desired,
                  std::memory_order mem_odr = std::memory_order_seq_cst)
  {
    // details::do_fetch_and_store(_atomic, _desired);
    details::do_compare_and_swap(
      _atomic, _atomic_desired,
      details::OpFunction<T>([](const T&, const T& y) { return y; }), mem_odr);
  }
  //------------------------------------------------------------------------//
  template <typename T>
  inline void set(std::atomic<T>& _atomic,
                  const std::atomic<T>& _atomic_desired,
                  std::memory_order mem_odr)
  {
    set(&_atomic, _atomic_desired, mem_odr);
  }
  //------------------------------------------------------------------------//
  template <typename T>
  inline void increment(std::atomic<T>* _atomic,
                        const std::atomic<T>& _atomic_increment,
                        std::memory_order mem_odr)
  {
    details::do_compare_and_swap(
      _atomic, _atomic_increment,
      details::OpFunction<T>([](const T& x, const T& y) { return x + y; }),
      mem_odr);
  }
  //------------------------------------------------------------------------//
  template <typename T>
  inline void decrement(std::atomic<T>* _atomic,
                        const std::atomic<T>& _atomic_decrement,
                        std::memory_order mem_odr)
  {
    details::do_compare_and_swap(
      _atomic, _atomic_decrement,
      details::OpFunction<T>([](const T& x, const T& y) { return x - y; }),
      mem_odr);
  }
  //------------------------------------------------------------------------//
  template <typename T>
  inline void multiply(std::atomic<T>* _atomic,
                       const std::atomic<T>& _atomic_factor,
                       std::memory_order mem_odr)
  {
    details::do_compare_and_swap(
      _atomic, _atomic_factor,
      details::OpFunction<T>([](const T& x, const T& y) { return x * y; }),
      mem_odr);
  }
  //------------------------------------------------------------------------//
  template <typename T>
  inline void divide(std::atomic<T>* _atomic,
                     const std::atomic<T>& _atomic_factor,
                     std::memory_order mem_odr)
  {
    details::do_compare_and_swap(
      _atomic, _atomic_factor,
      details::OpFunction<T>([](const T& x, const T& y) { return x / y; }),
      mem_odr);
  }
 
  //------------------------------------------------------------------------//
  //               STANDARD OVERLOAD                                        //
  //------------------------------------------------------------------------//
  template <typename T>
  inline void set(T* _non_atomic, const T& _desired)
  {
    *_non_atomic = _desired;
  }
  //------------------------------------------------------------------------//
  template <typename T>
  inline void set(T& _non_atomic, const T& _desired)
  {
    set(&_non_atomic, _desired);
  }
  //------------------------------------------------------------------------//
  //               STL PAIR OVERLOAD                                        //
  //------------------------------------------------------------------------//
  //
  //------------------------------------------------------------------------//
  //  WITH ATOMIC TEMPLATE TYPE AS SECOND PARAMETER
  //------------------------------------------------------------------------//
  template <typename T, typename U>
  inline void set(std::pair<std::atomic<T>, std::atomic<U>>* _atomic,
                  const std::pair<T, U>& _desired)
  {
    set(&_atomic->first, _desired.first);
    set(&_atomic->second, _desired.second);
  }
  //------------------------------------------------------------------------//
  template <typename T, typename U>
  inline void set(std::pair<std::atomic<T>, std::atomic<U>>& _atomic,
                  const std::pair<T, U>& _desired)
  {
    set(&_atomic, _desired);
  }
  //------------------------------------------------------------------------//
  template <typename T, typename U>
  inline void increment(std::pair<std::atomic<T>, std::atomic<U>>* _atomic,
                        const std::pair<T, U>& _increment)
  {
    increment(&_atomic->first, _increment.first);
    increment(&_atomic->second, _increment.second);
  }
  //------------------------------------------------------------------------//
  template <typename T, typename U>
  inline void decrement(std::pair<std::atomic<T>, std::atomic<U>>* _atomic,
                        const std::pair<T, U>& _decrement)
  {
    decrement(&_atomic->first, _decrement.first);
    decrement(&_atomic->second, _decrement.second);
  }
  //------------------------------------------------------------------------//
  template <typename T, typename U>
  inline void multiply(std::pair<std::atomic<T>, std::atomic<U>>* _atomic,
                       const std::pair<T, U>& _factor)
  {
    multiply(&_atomic->first, _factor.first);
    multiply(&_atomic->second, _factor.second);
  }
  //------------------------------------------------------------------------//
  template <typename T, typename U>
  inline void divide(std::pair<std::atomic<T>, std::atomic<U>>* _atomic,
                     const std::pair<T, U>& _factor)
  {
    divide(&_atomic->first, _factor.first);
    divide(&_atomic->second, _factor.second);
  }
  //------------------------------------------------------------------------//
  //  WITH ATOMICS AS SECOND PARAMETER
  //------------------------------------------------------------------------//
  template <typename T, typename U>
  inline void set(std::pair<std::atomic<T>, std::atomic<U>>* _atomic,
                  const std::pair<std::atomic<T>, std::atomic<U>>& _desired)
  {
    set(&_atomic->first, _desired.first);
    set(&_atomic->second, _desired.second);
  }
  //------------------------------------------------------------------------//
  template <typename T, typename U>
  inline void set(std::pair<std::atomic<T>, std::atomic<U>>& _atomic,
                  const std::pair<std::atomic<T>, std::atomic<U>>& _desired)
  {
    set(&_atomic, _desired);
  }
  //------------------------------------------------------------------------//
  template <typename T, typename U>
  inline void increment(
    std::pair<std::atomic<T>, std::atomic<U>>* _atomic,
    const std::pair<std::atomic<T>, std::atomic<U>>& _increment)
  {
    increment(&_atomic->first, _increment.first);
    increment(&_atomic->second, _increment.second);
  }
  //------------------------------------------------------------------------//
  template <typename T, typename U>
  inline void decrement(
    std::pair<std::atomic<T>, std::atomic<U>>* _atomic,
    const std::pair<std::atomic<T>, std::atomic<U>>& _decrement)
  {
    decrement(&_atomic->first, _decrement.first);
    decrement(&_atomic->second, _decrement.second);
  }
  //------------------------------------------------------------------------//
  template <typename T, typename U>
  inline void multiply(std::pair<std::atomic<T>, std::atomic<U>>* _atomic,
                       const std::pair<std::atomic<T>, std::atomic<U>>& _factor)
  {
    multiply(&_atomic->first, _factor.first);
    multiply(&_atomic->second, _factor.second);
  }
  //------------------------------------------------------------------------//
  template <typename T, typename U>
  inline void divide(std::pair<std::atomic<T>, std::atomic<U>>* _atomic,
                     const std::pair<std::atomic<T>, std::atomic<U>>& _factor)
  {
    divide(&_atomic->first, _factor.first);
    divide(&_atomic->second, _factor.second);
  }
  //------------------------------------------------------------------------//
 
  //------------------------------------------------------------------------//
  template <typename T>
  inline T get(const T& _non_atomic)
  {
    return _non_atomic;
  }
  //------------------------------------------------------------------------//
  template <typename T>
  inline T get(const T& _non_atomic, std::memory_order)
  {
    return _non_atomic;
  }
  //------------------------------------------------------------------------//
  template <typename T>
  inline T get(const std::atomic<T>& _atomic)
  {
    return _atomic.load();
  }
  //------------------------------------------------------------------------//
  template <typename T>
  inline T get(const std::atomic<T>& _atomic, std::memory_order mem_odr)
  {
    return _atomic.load(mem_odr);
  }
  //------------------------------------------------------------------------//
  template <typename T, typename U>
  inline std::pair<T, U> get(
    const std::pair<std::atomic<T>, std::atomic<U>>& _atomic)
  {
    return std::pair<T, U>(get(_atomic.first), get(_atomic.second));
  }
  //------------------------------------------------------------------------//
  template <typename T, typename U>
  inline std::pair<T, U> get(
    const std::pair<std::atomic<T>, std::atomic<U>>& _atomic,
    std::memory_order mem_odr)
  {
    return std::pair<T, U>(get(_atomic.first, mem_odr),
                           get(_atomic.second, mem_odr));
  }
  //------------------------------------------------------------------------//
 
  //------------------------------------------------------------------------//
  // for plain old data (POD) and pairs (e.g. std::pair<atomic<T>, atomic<U>>)
  template <typename _Tp_base, typename _Tp_atom>
  inline _Tp_base base(const _Tp_atom& _atomic)
  {
    return get(_atomic);
  }
  //------------------------------------------------------------------------//
 
}  // namespace atomics
 
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
 
#endif  // G4MULTITHREADED
 
#endif  // atomic_typedefs_hh_