Merge pull request #329 from KLayout/dvb

Dvb

src/db/db/dbNetlist.cc

@@ -396,6 +396,22 @@ void Netlist::flatten_circuit (Circuit *circuit)
   delete circuit;
 }
 
+void Netlist::flatten ()
+{
+  std::set<db::Circuit *> top_circuits;
+  size_t ntop = top_circuit_count ();
+  for (db::Netlist::top_down_circuit_iterator tc = begin_top_down (); tc != end_top_down () && ntop > 0; ++tc) {
+    top_circuits.insert (tc.operator-> ());
+    --ntop;
+  }
+
+  for (db::Netlist::bottom_up_circuit_iterator c = begin_bottom_up (); c != end_bottom_up(); ++c) {
+    if (top_circuits.find (c.operator-> ()) == top_circuits.end ()) {
+      flatten_circuit (c.operator-> ());
+    }
+  }
+}
+
 DeviceClass *Netlist::device_class_by_name (const std::string &name)
 {
   for (device_class_iterator d = begin_device_classes (); d != end_device_classes (); ++d) {

src/db/db/dbNetlist.h

@@ -174,6 +174,11 @@ public:
    */
   void flatten_circuit (Circuit *circuit);
 
+  /**
+   *  @brief Flattens the netlist
+   */
+  void flatten ();
+
   /**
    *  @brief Begin iterator for the circuits of the netlist (non-const version)
    */

src/db/db/gsiDeclDbNetlist.cc

@@ -1388,6 +1388,10 @@ Class<db::Netlist> decl_dbNetlist ("db", "Netlist",
     "A circuit with references (see \\has_refs?) should not be removed as the "
     "subcircuits calling it would afterwards point to nothing."
   ) +
+  gsi::method ("flatten", &db::Netlist::flatten,
+    "@brief Flattens all circuits of the netlist\n"
+    "After calling this method, only the top circuits will remain."
+  ) +
   gsi::method ("flatten_circuit", &db::Netlist::flatten_circuit, gsi::arg ("circuit"),
     "@brief Flattens a subcircuit\n"
     "This method will substitute all instances (subcircuits) of the given circuit by it's "

src/db/unit_tests/dbNetlistTests.cc

@@ -1188,6 +1188,20 @@ TEST(20_FlattenSubCircuit)
     "  device NMOS $4 (S=$4,G=$2,D=OUT) (L=0.25,W=0.95,AS=0,AD=0,PS=0,PD=0);\n"
     "end;\n"
   );
+
+  db::Netlist nl3;
+
+  nl3 = nl;
+  nl3.flatten ();
+
+  EXPECT_EQ (nl3.to_string (),
+    "circuit INV2 (IN=IN,$2=$2,OUT=OUT,$4=$4,$5=$5);\n"
+    "  device PMOS $1 (S=$5,G=IN,D=$2) (L=0.25,W=0.95,AS=0,AD=0,PS=0,PD=0);\n"
+    "  device PMOS $2 (S=$5,G=$2,D=OUT) (L=0.25,W=0.95,AS=0,AD=0,PS=0,PD=0);\n"
+    "  device NMOS $3 (S=$4,G=IN,D=$2) (L=0.25,W=0.95,AS=0,AD=0,PS=0,PD=0);\n"
+    "  device NMOS $4 (S=$4,G=$2,D=OUT) (L=0.25,W=0.95,AS=0,AD=0,PS=0,PD=0);\n"
+    "end;\n"
+  );
 }
 
 TEST(21_FlattenSubCircuit2)

src/lay/lay/doc/manual/lvs_compare.xml

@@ -46,7 +46,7 @@
   <pre>same_nets("LOGIC", "VDD", "VDD:P")</pre>
 
   <p>
-  In this example it is assumed that the power net is labelled "VDD" in the 
+  In this example it is assumed that the power net is labeled "VDD" in the 
   layout and called "VDD:P" in the schematic. Don't leave this statement in 
   the script for final verification as it may mask real errors.
   </p>
@@ -160,7 +160,8 @@ same_device_classes("NMOS_IN_LAYOUT", "NMOS_IN_SCHEMATIC")</pre>
   </p>
 
   <p>
-  In general, it's a good idea to include "align" before the "compare" step.
+  In general, it's a good idea to include "align" before "netlist.simplify" or 
+  similar netlist manipulation and the "compare" step.
   </p>
 
   <p>

src/lay/lay/doc/manual/lvs_connect.xml

@@ -70,7 +70,7 @@ connect(metal2, metal2_labels)</pre>
 
   <p>
   If labels are connected to metal layers, their text strings will be used to assign 
-  net names to the resulting nets. Ideally, one net is labelled with a single text 
+  net names to the resulting nets. Ideally, one net is labeled with a single text 
   or with texts with the same text string. In this case, the net name will 
   be non-ambiguous. If multiple labels with different strings are present on a net, 
   the net name will be made from a combination of these names.

src/lay/lay/doc/manual/lvs_intro.xml

@@ -156,6 +156,9 @@ connect_global(nwell, "NWELL")
 
 schematic("inv.cir")
 
+align              # flattens unpaired circuits 
+netlist.simplify   # removes floating nets, combines devices
+
 compare</pre>
 
   <p>
@@ -336,11 +339,35 @@ connect_global(nwell, "NWELL")</pre>
 
   <p>
   We have now provided all the essential inputs for the netlist formation.
-  We only have to specify the reference netlist:
+  We now have to specify the reference netlist:
   </p>
 
   <pre>schematic("inv.cir")</pre>
 
+  <p>
+  Two optional, but recommended steps are hierarchy alignment and extracted
+  netlist simplification:
+  </p>
+
+  <pre>align              # flattens unpaired circuits 
+netlist.simplify   # removes floating nets, combines devices
+  </pre>
+
+  <p>
+  "align" will remove circuits which are not present in the other netlist by
+  integrating their content into the parent cell. This will remove auxiliary cells
+  which are usually present in a layout but don't map to a schematic cell (e.g.
+  device PCells). "netlist.simplify" reduces the netlist by floating nets, 
+  performs device combination (e.g. fingered transistors). This method will 
+  also create pins from labeled nets in the top level circuit. 
+  </p>
+
+  <p>
+  The order should be "align", then "netlist.simplify". Both have to happen before
+  "compare" to be effective. "align" is described in <link href="/manual/lvs_compare.xml"/>,
+  "netlist.simplify" in <link href="/manual/lvs_tweaks.xml"/>.
+  </p>
+
   <p>
   Finally after having set this up, we can trigger the compare step:
   </p>
@@ -498,6 +525,9 @@ connect_global(ptie, "SUBSTRATE")
 
 schematic("inv2.cir")
 
+align
+netlist.simplify
+
 compare</pre>
 
   <p>

src/lay/lay/doc/manual/lvs_tweaks.xml

@@ -41,7 +41,7 @@
 
   <p>
   KLayout offers a function to create top-level pins using 
-  a simple heuristics: for every named (i.e. labelled) net in the top level 
+  a simple heuristics: for every named (i.e. labeled) net in the top level 
   circuit a pin will be created (<class_doc href="Netlist#make_top_level_pins"/>):
   </p>
 
@@ -199,9 +199,16 @@ netlist.purge_nets</pre>
 
   <p>
   <class_doc href="Netlist#simplify"/> is a wrapper for "make_top_level_pins",
-  "combine_devices" and "purge" in the recommended order:
+  "purge", "combine_devices" and "purge_nets" in this recommended order:
   </p>
 
   <pre>netlist.simplify</pre>
 
+  <p>
+  As a technical detail, "make_top_level_pins" is included in this sequence as with
+  pins, nets are not considered floating. So "purge_nets" will maintain pins for
+  labeled nets even if these nets are not connected to devices. This allows adding 
+  optional pins while maintaining the top level circuit's interface.
+  </p>
+
 </doc>

src/lay/lay/doc/manual/net_tracing.xml

@@ -101,7 +101,7 @@
     <li>Export all or selected nets to layout, save the netlist (with shapes) to a file, load it back from a file and manage
     the netlist database. Use the "File" menu button in the right upper corner.
     </li>
-    <li>Search for net names (if labelled) and circuits using the search edit box.
+    <li>Search for net names (if labeled) and circuits using the search edit box.
     </li>
     <li>Navigate through the history using the "back" and "forward" buttons at the top left.
     </li>

src/plugins/tools/net_tracer/lay_plugin/layNetTracerDialog.cc

@@ -559,13 +559,15 @@ NetTracerDialog::menu_activated (const std::string &symbol)
 
     layer_stack_clicked ();
 
-  } else if (symbol == "lay::trace_all_nets") {
+  } else if (symbol == "lay::trace_all_nets" || symbol == "lay::trace_all_nets_flat") {
+
+    bool flat = symbol == "lay::trace_all_nets_flat";
 
     const lay::CellView &cv = view ()->cellview (view ()->active_cellview_index ());
     if (cv.is_valid ()) {
       db::RecursiveShapeIterator si (cv->layout (), *cv.cell (), std::vector<unsigned int> ());
       std::auto_ptr <db::LayoutToNetlist> l2ndb (new db::LayoutToNetlist (si));
-      trace_all_nets (l2ndb.get (), cv);
+      trace_all_nets (l2ndb.get (), cv, flat);
       unsigned int l2ndb_index = view ()->add_l2ndb (l2ndb.release ());
       view ()->open_l2ndb_browser (l2ndb_index, view ()->index_of_cellview (&cv));
     }
@@ -1658,7 +1660,7 @@ NetTracerDialog::clear_markers ()
 }
 
 void
-NetTracerDialog::trace_all_nets (db::LayoutToNetlist *l2ndb, const lay::CellView &cv)
+NetTracerDialog::trace_all_nets (db::LayoutToNetlist *l2ndb, const lay::CellView &cv, bool flat)
 {
   db::NetTracerData tracer_data;
   if (! get_net_tracer_setup (cv, tracer_data)) {
@@ -1668,6 +1670,10 @@ NetTracerDialog::trace_all_nets (db::LayoutToNetlist *l2ndb, const lay::CellView
   tracer_data.configure_l2n (*l2ndb);
 
   l2ndb->extract_netlist ();
+
+  if (flat) {
+    l2ndb->netlist ()->flatten ();
+  }
 }
 
 }

src/plugins/tools/net_tracer/lay_plugin/layNetTracerDialog.h

@@ -118,7 +118,7 @@ private:
   void release_mouse ();
   db::NetTracerNet *do_trace (const db::DBox &start_search_box, const db::DBox &stop_search_box, bool trace_path);
   bool get_net_tracer_setup (const lay::CellView &cv, db::NetTracerData &data);
-  void trace_all_nets (db::LayoutToNetlist *l2ndb, const lay::CellView &cv);
+  void trace_all_nets (db::LayoutToNetlist *l2ndb, const lay::CellView &cv, bool flat);
 };
 
 }

src/plugins/tools/net_tracer/lay_plugin/layNetTracerPlugin.cc

@@ -69,7 +69,9 @@ public:
     lay::PluginDeclaration::get_menu_entries (menu_entries);
     menu_entries.push_back (lay::MenuEntry ("net_trace_group", "tools_menu.end"));
     menu_entries.push_back (lay::MenuEntry ("lay::net_trace", "net_trace", "tools_menu.end", tl::to_string (QObject::tr ("Trace Net"))));
-    menu_entries.push_back (lay::MenuEntry ("lay::trace_all_nets", "trace_all_nets", "tools_menu.end", tl::to_string (QObject::tr ("Trace All Nets"))));
+    menu_entries.push_back (lay::MenuEntry ("", "trace_all_nets_menu", "tools_menu.end", tl::to_string (QObject::tr ("Trace All Nets")), true));
+    menu_entries.push_back (lay::MenuEntry ("lay::trace_all_nets", "trace_all_nets", "tools_menu.trace_all_nets_menu.end", tl::to_string (QObject::tr ("Hierarchical"))));
+    menu_entries.push_back (lay::MenuEntry ("lay::trace_all_nets_flat", "trace_all_nets_flat", "tools_menu.trace_all_nets_menu.end", tl::to_string (QObject::tr ("Flat"))));
     menu_entries.push_back (lay::MenuEntry ("lay::edit_layer_stack", "edit_layer_stack", "tools_menu.end", tl::to_string (QObject::tr ("Edit Layer Stack"))));
   }