Trying to improve deep mode performance by avoiding multiple cell mapping operations due to partial hierarchy transfer. On the cost side, the hierarchy is always duplicated.

src/db/db/dbHierarchyBuilder.h

@@ -295,6 +295,7 @@ public:
    */
   void set_shape_receiver (HierarchyBuilderShapeReceiver *pipe);
 
+  virtual bool wants_all_cells () const { return true; }
   virtual void begin (const RecursiveShapeIterator *iter);
   virtual void end (const RecursiveShapeIterator *iter);
   virtual void enter_cell (const RecursiveShapeIterator *iter, const db::Cell *cell, const db::Box &region, const box_tree_type *complex_region);

src/db/db/dbRecursiveShapeIterator.cc

@@ -693,7 +693,11 @@ RecursiveShapeIterator::next_shape (RecursiveShapeReceiver *receiver) const
 
         //  determine whether the cell is empty with respect to the layers specified
         bool is_empty = false;
-        if (! m_has_layers) {
+        if (receiver && receiver->wants_all_cells ()) {
+
+          //  don't skip empty cells in that case
+
+        } else if (! m_has_layers) {
 
           is_empty = mp_layout->cell (m_inst->cell_index ()).bbox (m_layer).empty ();
 

src/db/db/dbRecursiveShapeIterator.h

@@ -913,6 +913,11 @@ public:
    */
   virtual ~RecursiveShapeReceiver () { }
 
+  /**
+   *  @brief Returns true, if the receivers wants the full hierarchy and not just non-empty cells
+   */
+  virtual bool wants_all_cells () const { return false; }
+
   /**
    *  @brief Called once when the iterator begins pushing
    */

src/lvs/unit_tests/lvsTests.cc

@@ -142,7 +142,7 @@ TEST(16_private)
 TEST(17_private)
 {
   test_is_long_runner ();
-  run_test (_this, "test_17.lylvs", "test_17b.cir.gz", "test_17.gds.gz", true, "test_17b_4.lvsdb");
+  run_test (_this, "test_17.lylvs", "test_17b.cir.gz", "test_17.gds.gz", true, "test_17b_5.lvsdb");
 }
 
 TEST(18_private)