temporaryMemory.hpp

/*
 * CoDiPack, a Code Differentiation Package
 *
 * Copyright (C) 2015-2024 Chair for Scientific Computing (SciComp), University of Kaiserslautern-Landau
 * Homepage: http://www.scicomp.uni-kl.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://www.scicomp.uni-kl.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 <algorithm>
#include <vector>
 
#include "../config.h"
#include "macros.hpp"
 
namespace codi {
 
  struct TemporaryMemory {
      static size_t constexpr InitialDataSize = 4 * 1024 * 1024;  
 
    private:
 
      std::vector<char> data;  
      size_t dataPos;          
 
    public:
 
      CODI_INLINE TemporaryMemory() : data(InitialDataSize), dataPos() {}
 
      CODI_INLINE TemporaryMemory(size_t initialSize) : data(initialSize), dataPos() {}
 
      CODI_INLINE bool isEmpty() {
        return 0 == dataPos;
      }
 
      template<typename T>
      CODI_INLINE T* alloc(size_t size) {
        codiAssert(dataPos + size * sizeof(T) <= data.size());
 
        T* castPointer = reinterpret_cast<T*>(&data.data()[dataPos]);
        dataPos += size * sizeof(T);
 
        return castPointer;
      }
 
      template<typename T, typename... Args>
      CODI_INLINE T* allocAndInit(Args&&... args) {
        T* value = alloc<T>(1);
        new (value) T(std::forward<Args>(args)...);
 
        return value;
      }
 
      CODI_INLINE void ensureSize(size_t newSize) {
        if (dataPos != 0) {
          CODI_EXCEPTION("Temporary memory can only be extended when no data is allocated.");
        }
 
        if (data.size() < newSize) {
          data.resize(newSize);
        }
      }
 
      CODI_INLINE void free() {
        // Clear used data.
        std::fill(data.begin(), data.begin() + dataPos, 0);
        dataPos = 0;
      }
  };
}