New testdata, bugfix: considering the case of partial net formation through soft, upward inter-instance connections. Enhanced reporting (report multiple partial nets of the same circuit at different instances)

src/db/db/dbLayoutToNetlistSoftConnections.cc

@@ -41,9 +41,7 @@ SoftConnectionNetGraph::SoftConnectionNetGraph ()
 
 void SoftConnectionNetGraph::add (const db::Net *net, SoftConnectionPinDir dir, const db::Pin *pin, size_t partial_net_count)
 {
-  //  limiting the partial net count to 1 means we report errors only once in the
-  //  hierarchy, not on every level
-  m_partial_net_count += std::min (size_t (1), partial_net_count);
+  m_partial_net_count += partial_net_count;
 
   //  this is where we make the decision about the partial nets ...
   if (! pin && dir == SoftConnectionPinDir::down ()) {
@@ -188,13 +186,13 @@ SoftConnectionInfo::representative_polygon (const db::Net *net, const db::Layout
   return db::DPolygon (bbox);
 }
 
-void SoftConnectionInfo::report_partial_nets (const db::Circuit *circuit, const SoftConnectionNetGraph &net_graph, db::LayoutToNetlist &l2n, const std::string &path, const db::DCplxTrans &trans, const std::string &top_cell, int &index, std::set<const db::Net *> &seen)
+void SoftConnectionInfo::report_partial_nets (const db::Circuit *circuit, const SoftConnectionNetGraph &net_graph, db::LayoutToNetlist &l2n, const std::string &path, const db::DCplxTrans &trans, const std::string &top_cell, int &index, std::set<std::pair<const db::Net *, db::DCplxTrans> > &seen)
 {
   for (auto cc = net_graph.begin_clusters (); cc != net_graph.end_clusters (); ++cc) {
 
     const db::Net *net = circuit->net_by_cluster_id (cc->first);
 
-    if (! seen.insert (net).second) {
+    if (! seen.insert (std::make_pair (net, trans)).second) {
       continue;
     }
 
@@ -263,7 +261,7 @@ void SoftConnectionInfo::report (db::LayoutToNetlist &l2n)
       l2n.log_entry (log_entry);
 
       int index = 0;
-      std::set<const db::Net *> seen;
+      std::set<std::pair<const db::Net *, db::DCplxTrans> > seen;
       report_partial_nets (c.operator-> (), *sc, l2n, c->name (), db::DCplxTrans (), c->name (), index, seen);
 
     }
@@ -390,7 +388,13 @@ void SoftConnectionInfo::get_net_connections_through_subcircuit (const db::SubCi
     const SoftConnectionNetGraph *scci = sci.get_net_graph_per_pin (pin);
     if (scci) {
 
-      partial_net_count += scci->partial_net_count ();
+      //  NOTE: limiting the partial net count here means we do report a partially connected once in the
+      //  hierarchy, not on every level.
+      //  Say, if you have two subcircuits, one (A) having 2 partial nets and the other (B) none. Then
+      //  (A) would be reported to partial nets only and when combining (A) and (B) we just need to check
+      //  whether B would also have partial nets. By not taking 2 + 0, but 1 + 0 the combination of (A)
+      //  and (B) does not give an error (error = number of partial nets > 1).
+      partial_net_count += std::min (size_t (1), scci->partial_net_count ());
 
       for (auto p = scci->begin_pins (); p != scci->end_pins (); ++p) {
         if (*p != pin->id ()) {

src/db/db/dbLayoutToNetlistSoftConnections.h

@@ -344,7 +344,7 @@ private:
    */
   std::set<size_t> net_connections_through_subcircuits (const db::Net *net, size_t &partial_net_count);
 
-  void report_partial_nets (const db::Circuit *circuit, const SoftConnectionNetGraph &cluster_info, LayoutToNetlist &l2n, const std::string &path, const db::DCplxTrans &trans, const std::string &top_cell, int &index, std::set<const Net *> &seen);
+  void report_partial_nets (const db::Circuit *circuit, const SoftConnectionNetGraph &cluster_info, LayoutToNetlist &l2n, const std::string &path, const db::DCplxTrans &trans, const std::string &top_cell, int &index, std::set<std::pair<const db::Net *, db::DCplxTrans> > &seen);
   db::DPolygon representative_polygon (const db::Net *net, const db::LayoutToNetlist &l2n, const db::CplxTrans &trans);
 };
 

testdata/lvs/soft_connect4.cir

@@ -0,0 +1,13 @@
+* Extracted by KLayout
+
+.SUBCKT TOP A Q SUBSTRATE
+X$1 \$5 \$1 Q SUBSTRATE INV
+X$2 \$5 A \$1 SUBSTRATE INV
+.ENDS TOP
+
+.SUBCKT INV \$2 \$4 \$5 SUBSTRATE
+M$1 \$2 \$4 \$5 \$2 PMOS L=0.25U W=0.95U AS=0.73625P AD=0.73625P PS=3.45U
++ PD=3.45U
+M$2 SUBSTRATE \$4 \$5 SUBSTRATE NMOS L=0.25U W=0.95U AS=0.73625P AD=0.73625P
++ PS=3.45U PD=3.45U
+.ENDS INV

testdata/lvs/soft_connect4.lvs

@@ -0,0 +1,93 @@
+
+$lvs_test_source && source($lvs_test_source)
+
+if $lvs_test_target_l2n
+  report_netlist($lvs_test_target_l2n)
+else
+  report_netlist
+end
+
+writer = write_spice(true, false)
+$lvs_test_target_cir && target_netlist($lvs_test_target_cir, writer, "Extracted by KLayout")
+
+deep
+
+# Drawing layers
+
+nwell       = input(1, 0)
+active      = input(2, 0)
+nplus       = input(2, 1)
+pplus       = input(2, 2)
+poly        = input(3, 0)
+poly_lbl    = input(3, 1)
+diff_cont   = input(4, 0)
+poly_cont   = input(5, 0)
+metal1      = input(6, 0)
+metal1_lbl  = input(6, 1)
+via1        = input(7, 0)
+metal2      = input(8, 0)
+metal2_lbl  = input(8, 1)
+
+# Bulk layer for terminal provisioning
+
+bulk        = polygon_layer
+
+psd = nil
+nsd = nil
+
+# Computed layers
+
+active_in_nwell       = active & nwell
+pactive               = active_in_nwell & pplus
+ntie                  = active_in_nwell & nplus
+pgate                 = pactive & poly
+psd                   = pactive - pgate
+
+active_outside_nwell  = active - nwell
+nactive               = active_outside_nwell & nplus
+ptie                  = active_outside_nwell & pplus
+ngate                 = nactive & poly
+nsd                   = nactive - ngate
+
+# Device extraction
+
+# PMOS transistor device extraction
+extract_devices(mos4("PMOS"), { "SD" => psd, "G" => pgate, "W" => nwell,
+                                "tS" => psd, "tD" => psd, "tG" => poly })
+
+# NMOS transistor device extraction
+extract_devices(mos4("NMOS"), { "SD" => nsd, "G" => ngate, "W" => bulk,
+                                "tS" => nsd, "tD" => nsd, "tG" => poly })
+
+# Define connectivity for netlist extraction
+
+# Inter-layer
+
+soft_connect(diff_cont, psd)
+soft_connect(diff_cont, nsd)
+soft_connect(diff_cont, ptie)
+soft_connect(diff_cont, ntie)
+soft_connect(ntie, nwell)
+soft_connect(poly_cont, poly)
+
+connect(diff_cont, metal1)
+connect(poly_cont, metal1)
+connect(metal1, via1)
+connect(via1, metal2)
+
+# attach labels
+connect(poly, poly_lbl)
+connect(metal1, metal1_lbl)
+connect(metal2, metal2_lbl)
+
+# Global
+connect_global(bulk, "SUBSTRATE")
+soft_connect_global(ptie, "SUBSTRATE")
+
+# Netlist section (NOTE: we only check log here)
+# for debugging: _make_soft_connection_diodes(true)
+netlist
+
+netlist.simplify
+
+