diff --git a/vpr7_x2p/vpr/SRC/device/rr_graph/tileable_rr_graph_builder.cpp b/vpr7_x2p/vpr/SRC/device/rr_graph/tileable_rr_graph_builder.cpp
index fe521ffa0..3d919ecc0 100644
--- a/vpr7_x2p/vpr/SRC/device/rr_graph/tileable_rr_graph_builder.cpp
+++ b/vpr7_x2p/vpr/SRC/device/rr_graph/tileable_rr_graph_builder.cpp
@@ -687,10 +687,15 @@ void alloc_rr_graph_fast_lookup(const DeviceCoordinator& device_size,
     if ((SOURCE == type) || (OPIN == type) ) {
       continue;
     }
-    rr_graph->rr_node_indices[type] = (t_ivec **) my_malloc(sizeof(t_ivec *) * device_size.get_x());
-    for (size_t i = 0; i < device_size.get_x(); ++i) {
-      rr_graph->rr_node_indices[type][i] = (t_ivec *) my_malloc(sizeof(t_ivec) * device_size.get_y());
-      for (size_t j = 0; j < device_size.get_y(); ++j) {
+    DeviceCoordinator actual_device_size(device_size);
+    /* Special for CHANX: we use (y,x) in allocation */
+    if (CHANX == type) {
+      actual_device_size.rotate();
+    }
+    rr_graph->rr_node_indices[type] = (t_ivec **) my_malloc(sizeof(t_ivec *) * actual_device_size.get_x());
+    for (size_t i = 0; i < actual_device_size.get_x(); ++i) {
+      rr_graph->rr_node_indices[type][i] = (t_ivec *) my_malloc(sizeof(t_ivec) * actual_device_size.get_y());
+      for (size_t j = 0; j < actual_device_size.get_y(); ++j) {
         rr_graph->rr_node_indices[type][i][j].nelem = 0;
         rr_graph->rr_node_indices[type][i][j].list = NULL;
       }
diff --git a/vpr7_x2p/vpr/SRC/fpga_x2p/base/fpga_x2p_unique_routing.c b/vpr7_x2p/vpr/SRC/fpga_x2p/base/fpga_x2p_unique_routing.c
index 45c67fa33..315f4f5ff 100644
--- a/vpr7_x2p/vpr/SRC/fpga_x2p/base/fpga_x2p_unique_routing.c
+++ b/vpr7_x2p/vpr/SRC/fpga_x2p/base/fpga_x2p_unique_routing.c
@@ -1338,10 +1338,10 @@ DeviceRRGSB build_device_rr_gsb(boolean output_sb_xml, char* sb_xml_dir,
   /* For each switch block, determine the size of array */
   for (size_t ix = 0; ix <= sb_range.get_x(); ++ix) {
     for (size_t iy = 0; iy <= sb_range.get_y(); ++iy) {
-      RRGSB rr_gsb = build_rr_gsb(sb_range, ix, iy,
-                                  LL_num_rr_nodes, LL_rr_node, 
-                                  LL_rr_node_indices, 
-                                  num_segments, LL_rr_indexed_data);
+      const RRGSB& rr_gsb = build_rr_gsb(sb_range, ix, iy,
+                                         LL_num_rr_nodes, LL_rr_node, 
+                                         LL_rr_node_indices, 
+                                         num_segments, LL_rr_indexed_data);
       /* sort drive_rr_nodes */
       sort_rr_gsb_drive_rr_nodes(rr_gsb);
       /* Add to device_rr_gsb */
@@ -1354,6 +1354,12 @@ DeviceRRGSB build_device_rr_gsb(boolean output_sb_xml, char* sb_xml_dir,
              "Backannotated %d switch blocks.\n",
              (nx + 1) * (ny + 1) );
 
+  /* End time count */
+  t_end = clock();
+ 
+  run_time_sec = (float)(t_end - t_start) / CLOCKS_PER_SEC;
+  vpr_printf(TIO_MESSAGE_INFO, "Backannotation of Switch Block took %g seconds\n\n", run_time_sec);  
+
 
   if (TRUE == output_sb_xml) {
     create_dir_path(sb_xml_dir);
@@ -1406,7 +1412,7 @@ DeviceRRGSB build_device_rr_gsb(boolean output_sb_xml, char* sb_xml_dir,
   t_end = clock();
  
   run_time_sec = (float)(t_end - t_start) / CLOCKS_PER_SEC;
-  vpr_printf(TIO_MESSAGE_INFO, "Routing architecture uniqifying took %g seconds\n", run_time_sec);  
+  vpr_printf(TIO_MESSAGE_INFO, "Routing architecture uniqifying took %g seconds\n\n", run_time_sec);  
 
   return LL_device_rr_gsb;
 }
diff --git a/vpr7_x2p/vpr/SRC/fpga_x2p/base/rr_blocks.cpp b/vpr7_x2p/vpr/SRC/fpga_x2p/base/rr_blocks.cpp
index f0d59fd9b..42fc21c17 100644
--- a/vpr7_x2p/vpr/SRC/fpga_x2p/base/rr_blocks.cpp
+++ b/vpr7_x2p/vpr/SRC/fpga_x2p/base/rr_blocks.cpp
@@ -2598,7 +2598,7 @@ void DeviceRRGSB::reserve_sb_unique_submodule_id(DeviceCoordinator& coordinator)
 }
 
 /* Resize rr_switch_block array is needed*/
-void DeviceRRGSB::resize_upon_need(DeviceCoordinator& coordinator) { 
+void DeviceRRGSB::resize_upon_need(const DeviceCoordinator& coordinator) { 
   if (coordinator.get_x() + 1 > rr_gsb_.size()) {
     rr_gsb_.resize(coordinator.get_x() + 1);
 
@@ -2622,7 +2622,7 @@ void DeviceRRGSB::resize_upon_need(DeviceCoordinator& coordinator) {
 }
 
 /* Add a switch block to the array, which will automatically identify and update the lists of unique mirrors and rotatable mirrors */
-void DeviceRRGSB::add_rr_gsb(DeviceCoordinator& coordinator, 
+void DeviceRRGSB::add_rr_gsb(const DeviceCoordinator& coordinator, 
                              const RRGSB& rr_gsb) {
   /* Resize upon needs*/
   resize_upon_need(coordinator);
diff --git a/vpr7_x2p/vpr/SRC/fpga_x2p/base/rr_blocks.h b/vpr7_x2p/vpr/SRC/fpga_x2p/base/rr_blocks.h
index d95c08d75..e87ee78c6 100644
--- a/vpr7_x2p/vpr/SRC/fpga_x2p/base/rr_blocks.h
+++ b/vpr7_x2p/vpr/SRC/fpga_x2p/base/rr_blocks.h
@@ -353,8 +353,8 @@ class DeviceRRGSB {
     void set_cb_conf_bits_msb(DeviceCoordinator& coordinator, t_rr_type cb_type, size_t conf_bits_msb); /* TODO: TOBE DEPRECATED!!! conf_bits should be initialized when creating a switch block!!! */
     void reserve(DeviceCoordinator& coordinator); /* Pre-allocate the rr_switch_block array that the device requires */ 
     void reserve_sb_unique_submodule_id(DeviceCoordinator& coordinator); /* Pre-allocate the rr_sb_unique_module_id matrix that the device requires */ 
-    void resize_upon_need(DeviceCoordinator& coordinator); /* Resize the rr_switch_block array if needed */ 
-    void add_rr_gsb(DeviceCoordinator& coordinator, const RRGSB& rr_gsb); /* Add a switch block to the array, which will automatically identify and update the lists of unique mirrors and rotatable mirrors */
+    void resize_upon_need(const DeviceCoordinator& coordinator); /* Resize the rr_switch_block array if needed */ 
+    void add_rr_gsb(const DeviceCoordinator& coordinator, const RRGSB& rr_gsb); /* Add a switch block to the array, which will automatically identify and update the lists of unique mirrors and rotatable mirrors */
     void build_unique_module(); /* Add a switch block to the array, which will automatically identify and update the lists of unique mirrors and rotatable mirrors */
     void clear(); /* clean the content */
   private: /* Internal cleaners */