Changed comments on t_heap and made pure virtual functions

Author: Nathan Shreve

vpr/src/route/heap_type.h

@@ -27,21 +27,21 @@ struct t_heap {
     t_heap_path* path_data;
 
     /**
-     * @brief Get <i>u.next</i>.
+     * @brief Get the next t_heap item in the linked list.
      */
     t_heap* next_heap_item() const {
         return u.next;
     }
 
     /**
-     * @brief Set <i>u.next</i>.
+     * @brief Set the next t_heap item in the linked list.
      */
     void set_next_heap_item(t_heap* next) {
         u.next = next;
     }
 
     /**
-     * @brief Get <i>u.prev_edge</i>.
+     * @brief Get the edge from the previous node used to reach the current node.
      *
      * @note
      * Be careful: will return 0 (a valid id!) if uninitialized.
@@ -52,7 +52,7 @@ struct t_heap {
     }
 
     /**
-     * @brief Set <i>u.prev_edge</i>.
+     * @brief Set the edge from the previous node used to reach the current node..
      */
     inline void set_prev_edge(RREdgeId edge) {
         static_assert(sizeof(uint32_t) == sizeof(RREdgeId));
@@ -61,7 +61,7 @@ struct t_heap {
 
   private:
     union {
-        ///@brief Pointer to the next s_heap structure in the free linked list.
+        ///@brief Pointer to the next t_heap structure in the free linked list.
         t_heap* next = nullptr;
 
         /**
@@ -121,12 +121,13 @@ class HeapStorage {
  * As a general rule, any t_heap objects returned from this interface,
  * **must** be HeapInterface::free'd before destroying the HeapInterface
  * instance. This ensure that no leaks are present in the users of the heap.
- * Violating this assumption may result in a assertion violation.
+ * Violating this assumption may result in an assertion violation.
  */
 class HeapInterface {
   public:
     virtual ~HeapInterface() {}
 
+  protected:
     /**
      * @brief Allocate a heap item.
      *
@@ -160,7 +161,7 @@ class HeapInterface {
      *  - empty_heap<BR>
      *  - build_heap<BR>
      *
-     *  @param grid
+     *  @param grid The FGPA device grid
      */
     virtual void init_heap(const DeviceGrid& grid) = 0;
 

vpr/src/route/k_ary_heap.h

@@ -24,9 +24,6 @@ class KAryHeap : public HeapInterface {
     void set_prune_limit(size_t max_index, size_t prune_limit) final;
     void free_all_memory() final;
 
-    virtual bool is_valid() const = 0;
-    virtual t_heap* get_heap_head() = 0;
-
   protected:
     /**
      * @brief The struct which the heap_ vector contains.
@@ -54,6 +51,9 @@ class KAryHeap : public HeapInterface {
         float cost;
     };
 
+    virtual bool is_valid() const = 0;
+    virtual t_heap* get_heap_head() = 0;
+
     /**
      * @return The number of elements in the heap.
      */