hacks/patch/scan_swap.patch

diff --git a/src/sta/network/ConcreteNetwork.cc b/src/sta/network/ConcreteNetwork.cc
index 6f8b842..8096f2e 100644
--- a/src/sta/network/ConcreteNetwork.cc
+++ b/src/sta/network/ConcreteNetwork.cc
@@ -1180,11 +1180,14 @@ ConcreteNetwork::replaceCell(Instance *inst,
   ConcreteCell *ccell = reinterpret_cast<ConcreteCell*>(cell);
   int port_count = ccell->portBitCount();
   ConcreteInstance *cinst = reinterpret_cast<ConcreteInstance*>(inst);
+  // Port count picked from Instance instead of Target cells-Dinesh A
+  ConcreteCell *instcell = reinterpret_cast<ConcreteCell*>(cinst->cell());
+  int inst_port_count = instcell->portBitCount();
   ConcretePin **pins = cinst->pins_;
   ConcretePin **rpins = new ConcretePin*[port_count];
-  for (int i = 0; i < port_count; i++)
-    rpins[i] = nullptr;
-  for (int i = 0; i < port_count; i++) {
+  for (int i = 0; i < port_count; i++) 
+    rpins[i] = pins[inst_port_count-1];
+  for (int i = 0; i < inst_port_count; i++) {
     ConcretePin *cpin = pins[i];
     if (cpin) {
       ConcretePort *pin_cport = reinterpret_cast<ConcretePort*>(cpin->port());
diff --git a/src/sta/tcl/NetworkEdit.tcl b/src/sta/tcl/NetworkEdit.tcl
index 5ce616b..bdd4057 100644
--- a/src/sta/tcl/NetworkEdit.tcl
+++ b/src/sta/tcl/NetworkEdit.tcl
@@ -236,6 +236,21 @@ proc replace_cell { instance lib_cell } {
   }
 }
 
+proc replace_to_scan_cell { instance } {
+  set inst [get_instance_error "instance" $instance]
+  set inst_cell [get_full_name [$inst liberty_cell]]
+  #Target scan cell __d to __sd
+  #example sky130_fd_sc_hd__dfrtp_2 to sky130_fd_sc_hd__sdfrtp_2
+  set inst_scell [regsub -all "__d" $inst_cell "__sd"]
+  puts "Info: Scan Swapping => Instance:$instance From:$inst_cell to:$inst_scell";
+  if { $inst_cell == "NULL"} {
+    return 0
+  }
+  set scell [get_lib_cell_warn "lib_cell" $inst_scell]
+  replace_cell_cmd $inst $scell
+  return 1
+}
+
 proc path_regexp {} {
   global hierarchy_separator
   set id_regexp "\[^${hierarchy_separator}\]+"
diff --git a/src/sta/tcl/Sta.tcl b/src/sta/tcl/Sta.tcl
index f3de994..a6e8e34 100644
--- a/src/sta/tcl/Sta.tcl
+++ b/src/sta/tcl/Sta.tcl
@@ -623,6 +623,7 @@ define_cmd_args "make_instance" {inst_path lib_cell}
 define_cmd_args "make_net" {}
 
 define_cmd_args "replace_cell" {instance lib_cell}
+define_cmd_args "replace_to_scan_cell" {instance}
 
 define_cmd_args "insert_buffer" {buffer_name buffer_cell net load_pins\
 				       buffer_out_net_name}