Performance optimizations (UniqueHazardPointer local copy; Tree node leaf/sentinel flags)

containers_cpp/include/embb/containers/internal/hazard_pointer-inl.h

@@ -422,12 +422,16 @@ const double embb::containers::internal::HazardPointer<GuardType>::
 template<typename Type>
 UniqueHazardPointer<Type>::
 UniqueHazardPointer()
-    : hazard_guard_(NULL), undefined_guard_(NULL), active_(false) {}
+    : hazard_guard_(NULL),
+      local_ptr_value_(NULL),
+      undefined_guard_(NULL),
+      active_(false) {}
 
 template<typename Type>
 UniqueHazardPointer<Type>::
 UniqueHazardPointer(AtomicTypePtr& hazard_guard, Type* undefined_guard)
     : hazard_guard_(&hazard_guard),
+      local_ptr_value_(hazard_guard_->Load()),
       undefined_guard_(undefined_guard),
       active_(LoadGuardedPointer() == undefined_guard_) {}
 
@@ -487,6 +491,7 @@ void UniqueHazardPointer<Type>::AdoptHazard(const UniqueHazardPointer& other) {
 template<typename Type>
 void UniqueHazardPointer<Type>::Swap(UniqueHazardPointer& other) {
   std::swap(hazard_guard_, other.hazard_guard_);
+  std::swap(local_ptr_value_, other.local_ptr_value_);
   std::swap(undefined_guard_, other.undefined_guard_);
   std::swap(active_, other.active_);
 }
@@ -517,12 +522,13 @@ void UniqueHazardPointer<Type>::ClearHazard() {
 
 template<typename Type>
 Type* UniqueHazardPointer<Type>::LoadGuardedPointer() const {
-  return hazard_guard_->Load();
+  return local_ptr_value_;
 }
 
 template<typename Type>
 void UniqueHazardPointer<Type>::StoreGuardedPointer(Type* ptr) {
   hazard_guard_->Store(ptr);
+  local_ptr_value_ = ptr;
 }
 
 template<typename Type>

containers_cpp/include/embb/containers/internal/hazard_pointer.h

@@ -692,6 +692,8 @@ class UniqueHazardPointer {
    * hazardous pointers
    */
   AtomicTypePtr* hazard_guard_;
+  /** Local copy of the guarded pointer value (used for optimization) */
+  Type*          local_ptr_value_;
   /** Dummy value used to clear the hazard guard from any hazards */
   Type*          undefined_guard_;
   /** Flag set to true when the guard is protecting some hazardous pointer */

containers_cpp/include/embb/containers/lock_free_chromatic_tree.h

@@ -33,6 +33,8 @@
 #include <embb/base/c/errors.h>
 #include <embb/base/mutex.h>
 #include <embb/containers/internal/hazard_pointer.h>
+#include <embb/containers/lock_free_tree_value_pool.h>
+#include <embb/containers/object_pool.h>
 
 namespace embb {
 namespace containers {
@@ -124,6 +126,20 @@ class ChromaticTreeNode {
   Node* GetRight() const;
 
   /**
+   * Checks if the node is a leaf.
+   * 
+   * @return \c true if node is a leaf, \c false otherwise
+   */
+  bool IsLeaf() const;
+
+  /**
+   * Checks if the node is a sentinel.
+   *
+   * @return \c true if node is a sentinel, \c false otherwise
+   */
+  bool IsSentinel() const;
+
+  /**
    * Tries to replace one of the child pointers that compares equal to
    * \c old_child with the \c new_child using an atomic compare-and-swap
    * operation. If neither left nor right child pointer is pointing to
@@ -166,13 +182,15 @@ class ChromaticTreeNode {
   ChromaticTreeNode(const ChromaticTreeNode&);
   ChromaticTreeNode& operator=(const ChromaticTreeNode&);
   
-  const Key          key_;       /**< Stored key. */
-  const Value        value_;     /**< Stored value. */
-  const int          weight_;    /**< Weight of the node. */
-  AtomicNodePtr      left_;      /**< Pointer to left child node. */
-  AtomicNodePtr      right_;     /**< Pointer to right child node. */
-  AtomicFlag         retired_;   /**< Retired (marked for deletion) flag. */
-  AtomicOperationPtr operation_; /**< Pointer to a tree operation object. */
+  const Key          key_;         /**< Stored key. */
+  const Value        value_;       /**< Stored value. */
+  const int          weight_;      /**< Weight of the node. */
+  const bool         is_leaf_;     /**< True if node is a leaf. */
+  const bool         is_sentinel_; /**< True if node is a sentinel. */
+  AtomicNodePtr      left_;        /**< Pointer to left child node. */
+  AtomicNodePtr      right_;       /**< Pointer to right child node. */
+  AtomicFlag         retired_;     /**< Retired (marked for deletion) flag. */
+  AtomicOperationPtr operation_;   /**< Pointer to a tree operation object. */
 };
 
 /**
@@ -692,24 +710,6 @@ class ChromaticTree {
               HazardNodePtr& grandparent);
   
   /**
-   * Checks whether the given node is a leaf.
-   * 
-   * \param[IN] node Node to be checked
-   * 
-   * \return \c true if the given node is a leaf, \c false otherwise
-   */
-  bool IsLeaf(const Node* node) const;
-  
-  /**
-   * Checks whether the given node is a sentinel node.
-   * 
-   * \param[IN] node Node to be checked
-   * 
-   * \return \c true if the given node is a sentinel node, \c false otherwise
-   */
-  bool IsSentinel(const Node* node) const;
-  
-  /**
    * Checks whether the given node has a specified child node.
    * 
    * \param[IN] parent Parent node