smallObjectAllocator_inl.h

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// ============================================================================
#include <agrum/core/smallobjectallocator/fixedAllocator.h>
#include <agrum/core/smallobjectallocator/smallObjectAllocator.h>
// ============================================================================


namespace gum {

  // ############################################################################
  // @name Constructors / Destructors
  // ############################################################################

  // ============================================================================
  /*
   * Constructor.
   * @param chunkSize is the size of a chunk in bytes.
   * @param maxObjectSize is the max size of object to be considered small
   * Greater object than maxObjectSize will be forwarded to op new.
   */
  // ============================================================================
  INLINE SmallObjectAllocator::SmallObjectAllocator() :
      __chunkSize(GUM_DEFAULT_CHUNK_SIZE),
      __maxObjectSize(GUM_DEFAULT_MAX_OBJECT_SIZE) {
    __pool.setKeyUniquenessPolicy(false);
    GUM_CONSTRUCTOR(SmallObjectAllocator);
    nbAllocation = 0;
    nbDeallocation = 0;

    // SmallObjectAllocator::Instance will create a static SmallObjectAllocator and
    // a HashTable that will not be deleted ...
    // so we inform our leak detector not to count those 2 objects
    GUM_DESTRUCTOR(SmallObjectAllocator);
    GUM_DESTRUCTOR(HashTable);
  }

  // ============================================================================
  // Destructor.
  // ============================================================================
  INLINE SmallObjectAllocator::~SmallObjectAllocator() {
    GUM_DESTRUCTOR(SmallObjectAllocator);
    for (__Pool::iterator pit = __pool.begin(); pit != __pool.end(); ++pit)
      delete pit.val();
  }

  INLINE SmallObjectAllocator& SmallObjectAllocator::instance() {
    static SmallObjectAllocator soa;

    return soa;
  }

  // ############################################################################
  // @name Allocator / Deallocator
  // ############################################################################

  // ============================================================================
  // Allocates an object
  // ============================================================================
  INLINE void* SmallObjectAllocator::allocate(const size_t& objectSize) {
    // Small Object Allocator called for an object of size equals to 0
    GUM_ASSERT(objectSize > 0);

    // If objectSize is greater than maxObjectSize, normal new is called
    if (objectSize > __maxObjectSize) return new unsigned char[objectSize];

    void* ret;
#pragma omp critical(soa)
    {
      //
      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;
        unsigned char numBlocks = static_cast< unsigned char >(nb);

        FixedAllocator* newFa = new FixedAllocator(Size(objectSize), numBlocks);
        __pool.set(Size(objectSize), newFa);
      }
      nbAllocation++;

      ret = __pool[Size(objectSize)]->allocate();
    }
    return ret;
  }

  // ============================================================================
  // Deallocates an object
  // @param pDeallocatedObject is the object to be deallocated
  // @param objectSize is the size of that object (useful for faster
  // deallocation)
  // ============================================================================
  INLINE void SmallObjectAllocator::deallocate(void*         pDeallocatedObject,
                                               const size_t& objectSize) {
    // Small Object Allocator called for an object of size equals to 0
    GUM_ASSERT(objectSize > 0);

    // If objectSize is greater than maxObjectSize, normal new is called
    if (objectSize > __maxObjectSize) {
      delete[](unsigned char*) pDeallocatedObject;
      return;
    }

#pragma omp critical(soa)
    {
      //      std::cout << "Deallocating " << pDeallocatedObject << std::endl;
      __pool[Size(objectSize)]->deallocate(pDeallocatedObject);
      nbDeallocation++;
    }
  }

}   // namespace gum