WIP: Bugfix - hierarchy was dropping instances.

src/db/db/dbHierarchyBuilder.cc

@@ -154,6 +154,7 @@ HierarchyBuilder::reset ()
   m_initial_pass = true;
   mp_initial_cell = 0;
 
+  m_cells_to_be_filled.clear ();
   m_cell_map.clear ();
   m_cells_seen.clear ();
   m_cell_stack.clear ();
@@ -206,9 +207,15 @@ void
 HierarchyBuilder::enter_cell (const RecursiveShapeIterator * /*iter*/, const db::Cell * /*cell*/, const db::Box & /*region*/, const box_tree_type * /*complex_region*/)
 {
   tl_assert (m_cm_entry != m_cell_map.end () && m_cm_entry != cell_map_type::const_iterator ());
+
   m_cells_seen.insert (m_cm_entry->first);
 
-  m_cell_stack.push_back (std::make_pair (m_cm_new_entry, &mp_target->cell (m_cm_entry->second)));
+  bool new_cell = (m_cells_to_be_filled.find (m_cm_entry->second) != m_cells_to_be_filled.end ());
+  if (new_cell) {
+    m_cells_to_be_filled.erase (m_cm_entry->second);
+  }
+
+  m_cell_stack.push_back (std::make_pair (new_cell, &mp_target->cell (m_cm_entry->second)));
 }
 
 void
@@ -230,6 +237,7 @@ HierarchyBuilder::new_inst (const RecursiveShapeIterator *iter, const db::CellIn
       db::cell_index_type new_cell = mp_target->add_cell (iter->layout ()->cell_name (inst.object ().cell_index ()));
       m_cm_entry = m_cell_map.insert (std::make_pair (key, new_cell)).first;
       m_cm_new_entry = true;
+      m_cells_to_be_filled.insert (new_cell);
     }
 
     //  for new cells, create this instance
@@ -277,6 +285,7 @@ HierarchyBuilder::new_inst_member (const RecursiveShapeIterator *iter, const db:
       db::cell_index_type new_cell = mp_target->add_cell ((std::string (iter->layout ()->cell_name (inst.object ().cell_index ())) + suffix).c_str ());
       m_cm_entry = m_cell_map.insert (std::make_pair (key, new_cell)).first;
       m_cm_new_entry = true;
+      m_cells_to_be_filled.insert (new_cell);
     }
 
     //  for a new cell, create this instance

src/db/db/dbHierarchyBuilder.h

@@ -248,6 +248,7 @@ private:
   db::RecursiveShapeIterator m_source;
   cell_map_type m_cell_map;
   std::set<cell_map_type::key_type> m_cells_seen;
+  std::set<db::cell_index_type> m_cells_to_be_filled;
   cell_map_type::const_iterator m_cm_entry;
   bool m_cm_new_entry;
   unsigned int m_target_layer;

src/db/unit_tests/dbHierarchyBuilderTests.cc

@@ -467,3 +467,34 @@ TEST(5_CompareRecursiveShapeIterators)
   }
 }
 
+TEST(6_DisjunctLayersPerHierarchyBranch)
+{
+  db::Layout ly;
+  {
+    std::string fn (tl::testsrc ());
+    fn += "/testdata/algo/hierarchy_builder_l4.gds";
+    tl::InputStream stream (fn);
+    db::Reader reader (stream);
+    reader.read (ly);
+  }
+
+  db::Layout target;
+  db::HierarchyBuilder builder (&target);
+
+  for (db::Layout::layer_iterator li = ly.begin_layers (); li != ly.end_layers (); ++li) {
+
+    unsigned int li1 = (*li).first;
+    unsigned int target_layer = target.insert_layer (*(*li).second);
+    builder.set_target_layer (target_layer);
+
+    db::cell_index_type top_cell_index = *ly.begin_top_down ();
+    db::RecursiveShapeIterator iter (ly, ly.cell (top_cell_index), li1);
+
+    iter.push (&builder);
+
+  }
+
+  CHECKPOINT();
+  db::compare_layouts (_this, target, tl::testsrc () + "/testdata/algo/hierarchy_builder_au_l4.gds");
+}
+