smallObjectAllocator.cpp

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 *       - Christophe GONZALES(_at_AMU)                                     *
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 *       - Pierre-Henri WUILLEMIN(_at_LIP6)                                 *
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// ============================================================================
#include <agrum/base/core/smallobjectallocator/fixedAllocator.h>
#include <agrum/base/core/smallobjectallocator/smallObjectAllocator.h>
 
// ============================================================================
namespace gum {
 
 
  /*
   * @variable The default size of chunck of memory.
   * These chuncks are pre-allocated memory space which are
   * then split in small memory space of the size of a small object
   */
  const size_t SmallObjectAllocator::GUM_DEFAULT_CHUNK_SIZE = 8096;
 
  /*
   * @variable The default maximal size under which an object is considered
   * small. If an object size is over this limit, the normal new allocator is
   * called.
   */
  const size_t SmallObjectAllocator::GUM_DEFAULT_MAX_OBJECT_SIZE = 512;
 
  void* SmallObjectAllocator::allocate(const size_t& objectSize) {
    // Small Object Allocator called for an object of size equals to 0
    GUM_ASSERT(objectSize > 0);
 
    std::lock_guard< std::mutex > lock(_mutex_);
 
    // If objectSize is greater than maxObjectSize, normal new is called
    if (objectSize > _maxObjectSize_) return new unsigned char[objectSize];
 
    //
    if (!_pool_.exists(Size(objectSize))) {
      // Calcul du nombre de block par chunk pour des objets de cette taille
      std::size_t nb = _chunkSize_ / Size(objectSize);
      if (nb > UCHAR_MAX) nb = UCHAR_MAX;
      auto numBlocks = static_cast< unsigned char >(nb);
 
      auto* newFa = new FixedAllocator(Size(objectSize), numBlocks);
      _pool_.set(Size(objectSize), newFa);
    }
    nbAllocation++;
 
    return _pool_[Size(objectSize)]->allocate();
  }
}   // namespace gum
 
#ifdef GUM_NO_INLINE
#  include <agrum/base/core/smallobjectallocator/smallObjectAllocator_inl.h>
#endif