memberStore.hpp

/*
 * CoDiPack, a Code Differentiation Package
 *
 * Copyright (C) 2015-2024 Chair for Scientific Computing (SciComp), University of Kaiserslautern-Landau
 * Homepage: http://scicomp.rptu.de
 * Contact:  Prof. Nicolas R. Gauger (codi@scicomp.uni-kl.de)
 *
 * Lead developers: Max Sagebaum, Johannes Blühdorn (SciComp, University of Kaiserslautern-Landau)
 *
 * This file is part of CoDiPack (http://scicomp.rptu.de/software/codi).
 *
 * CoDiPack is free software: you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * CoDiPack is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * See the GNU General Public License for more details.
 * You should have received a copy of the GNU
 * General Public License along with CoDiPack.
 * If not, see <http://www.gnu.org/licenses/>.
 *
 * For other licensing options please contact us.
 *
 * Authors:
 *  - SciComp, University of Kaiserslautern-Landau:
 *    - Max Sagebaum
 *    - Johannes Blühdorn
 *    - Former members:
 *      - Tim Albring
 */
#pragma once
 
#include <new>
#include <utility>
 
#include "../config.h"
#include "../misc/macros.hpp"
 
namespace codi {
 
  template<typename T_Type, typename T_Parent, bool T_storeStatic = false>
  struct MemberStore {
    public:
 
      using Type = T_Type;                         // Default declaration breaks auto completion.
      using Parent = CODI_DD(T_Parent, CODI_ANY);  
 
      static bool constexpr storeStatic = T_storeStatic;  
 
    private:
 
      Type member;
 
    public:
 
      template<typename... Args>
      MemberStore(Args&&... args) : member(std::forward<Args>(args)...) {}
 
      Type& get() {
        return member;
      }
 
      Type const& get() const {
        return member;
      }
  };
 
  template<typename T_Type, typename T_Parent>
  struct MemberStore<T_Type, T_Parent, true> {
    public:
 
      using Type = T_Type;                         
      using Parent = CODI_DD(T_Parent, CODI_ANY);  
 
      static bool constexpr storeStatic = true;  
 
    private:
 
      static char member[sizeof(Type)];
      static bool isInitialized;
 
    public:
 
      template<typename... Args>
      MemberStore(Args&&... args) {
        if (!isInitialized) {
          isInitialized = true;
          new (member) Type(std::forward<Args>(args)...);
        }
      }
 
      CODI_INLINE Type& get() {
        return *((Type*)MemberStore::member);
      }
 
      CODI_INLINE Type const& get() const {
        return *((Type const*)MemberStore::member);
      }
  };
 
#ifndef DOXYGEN_DISABLE
  template<typename Type, typename Parent>
  char MemberStore<Type, Parent, true>::member[sizeof(Type)] = {};
 
  template<typename Type, typename Parent>
  bool MemberStore<Type, Parent, true>::isInitialized = false;
#endif
}