diff --git a/vpr7_x2p/vpr/SRC/fpga_x2p/base/fpga_x2p_backannotate_utils.c b/vpr7_x2p/vpr/SRC/fpga_x2p/base/fpga_x2p_backannotate_utils.c
index 9a219dcd3..8d1558e1d 100644
--- a/vpr7_x2p/vpr/SRC/fpga_x2p/base/fpga_x2p_backannotate_utils.c
+++ b/vpr7_x2p/vpr/SRC/fpga_x2p/base/fpga_x2p_backannotate_utils.c
@@ -3129,7 +3129,6 @@ void spice_backannotate_vpr_post_route_info(t_det_routing_arch RoutingArch,
   /* Build Array for each Switch block and Connection block */ 
   vpr_printf(TIO_MESSAGE_INFO, "Collecting detailed information for each Switch block...\n");
   alloc_and_build_switch_blocks_info(RoutingArch, num_rr_nodes, rr_node, rr_node_indices);
-  device_rr_switch_block = build_device_rr_switch_blocks(num_rr_nodes, rr_node, rr_node_indices);
 
   vpr_printf(TIO_MESSAGE_INFO, "Collecting detailed information for each to Connection block...\n");
   alloc_and_build_connection_blocks_info(RoutingArch, num_rr_nodes, rr_node, rr_node_indices);
diff --git a/vpr7_x2p/vpr/SRC/fpga_x2p/base/fpga_x2p_setup.c b/vpr7_x2p/vpr/SRC/fpga_x2p/base/fpga_x2p_setup.c
index c16950462..fd1857e0e 100644
--- a/vpr7_x2p/vpr/SRC/fpga_x2p/base/fpga_x2p_setup.c
+++ b/vpr7_x2p/vpr/SRC/fpga_x2p/base/fpga_x2p_setup.c
@@ -1400,6 +1400,7 @@ void fpga_x2p_setup(t_vpr_setup vpr_setup,
 
     /* Assign Gobal variable: build the Routing Resource Channels */
     device_rr_chan = build_device_rr_chan(num_rr_nodes, rr_node, rr_node_indices, Arch->num_segments, rr_indexed_data);
+    device_rr_switch_block = build_device_rr_switch_blocks(num_rr_nodes, rr_node, rr_node_indices);
 
     /* Rotatable will be done in the next step 
     identify_rotatable_switch_blocks(); 
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 920340d1e..ee681c73f 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
@@ -1037,6 +1037,7 @@ RRSwitchBlock build_rr_switch_block(int sb_x, int sb_y,
     rr_switch_block.clear_ipin_nodes(side_manager.get_side());
 
     /* Free */
+    my_free(chan_rr_node);
     temp_num_opin_rr_nodes[0] = 0;
     my_free(temp_opin_rr_node[0]);
     temp_num_opin_rr_nodes[1] = 0;
@@ -1082,6 +1083,10 @@ DeviceRRSwitchBlock build_device_rr_switch_blocks(int LL_num_rr_nodes,
              "Detect %d independent switch blocks from %d switch blocks.\n",
              LL_device_rr_switch_block.get_num_unique_mirror(), (nx + 1) * (ny + 1) );
 
+  vpr_printf(TIO_MESSAGE_INFO, 
+             "Detect %d rotatable unique switch blocks from %d switch blocks.\n",
+             LL_device_rr_switch_block.get_num_rotatable_mirror(), (nx + 1) * (ny + 1) );
+
   return LL_device_rr_switch_block;
 }
 
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 6d79b5646..e56832b46 100644
--- a/vpr7_x2p/vpr/SRC/fpga_x2p/base/rr_blocks.cpp
+++ b/vpr7_x2p/vpr/SRC/fpga_x2p/base/rr_blocks.cpp
@@ -336,6 +336,16 @@ size_t RRSwitchBlock::get_chan_width(enum e_side side) const {
   return chan_node_[side_manager.to_size_t()].size(); 
 }
 
+/* Get the maximum number of routing tracks on all sides */
+size_t RRSwitchBlock::get_max_chan_width() const {
+  size_t max_chan_width = 0;
+  for (size_t side = 0; side < get_num_sides(); ++side) {
+    Side side_manager(side);
+    max_chan_width = std::max(max_chan_width, get_chan_width(side_manager.get_side()));
+  }
+  return max_chan_width;
+} 
+
 /* Get the direction of a rr_node at a given side and track_id */
 enum PORTS RRSwitchBlock::get_chan_node_direction(enum e_side side, size_t track_id) const {
   Side side_manager(side);
@@ -783,12 +793,12 @@ void RRSwitchBlock::rotate_chan_node(size_t offset) {
     size_t rotate_begin = 0;
     size_t rotate_end = 0;
     /* Partition the chan nodes on this side, depending on its length */
+    /* skip this side if there is no nodes */
+    if (0 == get_chan_width(side_manager.get_side())) {
+      continue;
+    }
     for (size_t inode = 0; inode < get_chan_width(side_manager.get_side()) - 1; ++inode) {
-      if ( ( (chan_node_[side][inode]->xlow  != chan_node_[side][inode + 1]->xlow) 
-          || (chan_node_[side][inode]->ylow  != chan_node_[side][inode + 1]->ylow) 
-          || (chan_node_[side][inode]->xhigh != chan_node_[side][inode + 1]->xhigh) 
-          || (chan_node_[side][inode]->yhigh != chan_node_[side][inode + 1]->yhigh)
-          || (chan_node_direction_[side][inode] != chan_node_direction_[side][inode + 1]))
+      if ( ( abs(chan_node_[side][inode]->yhigh - chan_node_[side][inode]->ylow + chan_node_[side][inode]->xhigh - chan_node_[side][inode]->xlow) != abs(chan_node_[side][inode + 1]->yhigh - chan_node_[side][inode + 1]->ylow + chan_node_[side][inode + 1]->xhigh - chan_node_[side][inode + 1]->xlow)) 
         || ( inode == get_chan_width(side_manager.get_side()) - 2) ) {
         /* Record the upper bound  */
         if ( inode == get_chan_width(side_manager.get_side()) - 2)  {
@@ -797,7 +807,13 @@ void RRSwitchBlock::rotate_chan_node(size_t offset) {
           rotate_end = inode;
         }
         /* Make sure offset is in range */
-        assert (offset < rotate_end - rotate_begin);
+        /* skip this side if there is no nodes */
+        if (0 >= rotate_end - rotate_begin) {
+          /* Update the lower bound  */
+          rotate_begin = inode + 1;
+          continue;
+        }
+        assert(offset < rotate_end - rotate_begin + 1);
         /* Find a group split, rotate */
         std::rotate(chan_node_.begin() + rotate_begin, 
                     chan_node_.begin() + rotate_begin + offset, 
@@ -822,6 +838,10 @@ void RRSwitchBlock::rotate_opin_node(size_t offset) {
     Side side_manager(side);
     size_t rotate_begin = 0;
     size_t rotate_end = 0;
+    /* skip this side if there is no nodes */
+    if (0 == get_num_opin_nodes(side_manager.get_side())) {
+      continue;
+    }
     /* Partition the opin nodes on this side, depending on grids */
     for (size_t inode = 0; inode < get_num_opin_nodes(side_manager.get_side()) - 1; ++inode) {
       if ( ( (opin_node_[side][inode]->xlow  != opin_node_[side][inode + 1]->xlow) 
@@ -836,8 +856,14 @@ void RRSwitchBlock::rotate_opin_node(size_t offset) {
         } else {
           rotate_end = inode;
         }
+        /* skip this side if there is no nodes */
+        if (0 >= rotate_end - rotate_begin) {
+          /* Update the lower bound  */
+          rotate_begin = inode + 1;
+          continue;
+        }
         /* Make sure offset is in range */
-        assert (offset < rotate_end - rotate_begin);
+        assert (offset < rotate_end - rotate_begin + 1);
         /* Find a group split, rotate */
         std::rotate(opin_node_.begin() + rotate_begin, 
                     opin_node_.begin() + rotate_begin + offset, 
@@ -1153,9 +1179,12 @@ void DeviceRRSwitchBlock::set_rr_switch_block_conf_bits_msb(DeviceCoordinator& c
 void DeviceRRSwitchBlock::reserve(DeviceCoordinator& coordinator) { 
   rr_switch_block_.resize(coordinator.get_x());
   rr_switch_block_mirror_id_.resize(coordinator.get_x());
+  rr_switch_block_rotatable_mirror_id_.resize(coordinator.get_x());
+
   for (size_t x = 0; x < coordinator.get_x(); ++x) {
     rr_switch_block_[x].resize(coordinator.get_y()); 
     rr_switch_block_mirror_id_[x].resize(coordinator.get_y()); 
+    rr_switch_block_rotatable_mirror_id_[x].resize(coordinator.get_y()); 
   }
   return;
 }
@@ -1165,11 +1194,13 @@ void DeviceRRSwitchBlock::resize_upon_need(DeviceCoordinator& coordinator) {
   if (coordinator.get_x() + 1 > rr_switch_block_.capacity()) {
     rr_switch_block_.resize(coordinator.get_x());
     rr_switch_block_mirror_id_.resize(coordinator.get_x());
+    rr_switch_block_rotatable_mirror_id_.resize(coordinator.get_x());
   }
 
   if (coordinator.get_y() + 1 > rr_switch_block_[coordinator.get_x()].capacity()) {
     rr_switch_block_[coordinator.get_x()].resize(coordinator.get_y());
     rr_switch_block_mirror_id_[coordinator.get_x()].resize(coordinator.get_y());
+    rr_switch_block_rotatable_mirror_id_[coordinator.get_x()].resize(coordinator.get_y());
   }
   
   return;
@@ -1179,6 +1210,7 @@ void DeviceRRSwitchBlock::resize_upon_need(DeviceCoordinator& coordinator) {
 void DeviceRRSwitchBlock::add_rr_switch_block(DeviceCoordinator& coordinator, 
                                               RRSwitchBlock& rr_switch_block) {
   bool is_unique_mirror = true;
+  bool is_rotatable_mirror = true;
 
   /* Resize upon needs*/
   resize_upon_need(coordinator);
@@ -1203,7 +1235,33 @@ void DeviceRRSwitchBlock::add_rr_switch_block(DeviceCoordinator& coordinator,
     rr_switch_block_mirror_id_[coordinator.get_x()][coordinator.get_y()] = unique_mirror_.size() - 1; 
   }
 
-  /* TODO: add rotatable mirror support */
+  /* add rotatable mirror support */
+  for (size_t mirror_id = 0; mirror_id < get_num_rotatable_mirror(); ++mirror_id) {
+    RRSwitchBlock rotate_mirror = rr_switch_block;
+    /* Try to rotate as many times as the maximum channel width in this switch block
+     * This may not fully cover all the rotation possibility but may be enough now  
+     */
+    for (size_t offset = 0; offset < rr_switch_block.get_max_chan_width(); ++offset) {
+      rotate_mirror.rotate(1);
+      if (true == get_switch_block(unique_mirror_[mirror_id]).is_mirror(rotate_mirror)) {
+        /* This is a mirror, raise the flag and we finish */
+        is_rotatable_mirror = false;
+        /* Record the id of unique mirror */
+        rr_switch_block_rotatable_mirror_id_[coordinator.get_x()][coordinator.get_y()] = mirror_id; 
+        break;
+      }
+    }
+    if (false == is_rotatable_mirror) {
+      break;
+    }
+  }
+  /* Add to list if this is a unique mirror*/
+  if (true == is_rotatable_mirror) {
+    rotatable_mirror_.push_back(coordinator);
+    /* Record the id of unique mirror */
+    rr_switch_block_rotatable_mirror_id_[coordinator.get_x()][coordinator.get_y()] = rotatable_mirror_.size() - 1; 
+  }
+
 
   return;
 } 
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 bbd665bc9..aba328fa8 100644
--- a/vpr7_x2p/vpr/SRC/fpga_x2p/base/rr_blocks.h
+++ b/vpr7_x2p/vpr/SRC/fpga_x2p/base/rr_blocks.h
@@ -126,6 +126,7 @@ class RRSwitchBlock {
     DeviceCoordinator get_coordinator() const; /* Get the number of sides of this SB */
     size_t get_num_sides() const; /* Get the number of sides of this SB */
     size_t get_chan_width(enum e_side side) const; /* Get the number of routing tracks on a side */
+    size_t get_max_chan_width() const; /* Get the maximum number of routing tracks on all sides */
     enum PORTS get_chan_node_direction(enum e_side side, size_t track_id) const; /* Get the direction of a rr_node at a given side and track_id */
     t_rr_node* get_chan_node(enum e_side side, size_t track_id) const; /* get a rr_node at a given side and track_id */
     size_t get_num_ipin_nodes(enum e_side side) const; /* Get the number of IPIN rr_nodes on a side */
@@ -223,6 +224,7 @@ class DeviceRRSwitchBlock {
   private: /* Internal Data */
     std::vector< std::vector<RRSwitchBlock> > rr_switch_block_;
     std::vector< std::vector<size_t> > rr_switch_block_mirror_id_; /* A map from rr_switch_block to its unique mirror */
+    std::vector< std::vector<size_t> > rr_switch_block_rotatable_mirror_id_; /* A map from rr_switch_block to its unique mirror */
     std::vector<DeviceCoordinator> unique_mirror_; 
     std::vector<DeviceCoordinator> rotatable_mirror_; 
 };
diff --git a/vpr7_x2p/vpr/go_fpga_verilog.sh b/vpr7_x2p/vpr/go_fpga_verilog.sh
index 969ebceb3..05c2a589a 100755
--- a/vpr7_x2p/vpr/go_fpga_verilog.sh
+++ b/vpr7_x2p/vpr/go_fpga_verilog.sh
@@ -39,6 +39,6 @@ rm -rf $verilog_output_dirpath/$verilog_output_dirname
 #valgrind 
 ./vpr $arch_xml_file $blif_file --full_stats --nodisp --activity_file $act_file --fpga_verilog --fpga_verilog_dir $verilog_output_dirpath/$verilog_output_dirname --fpga_x2p_rename_illegal_port --fpga_bitstream_generator --fpga_verilog_print_top_testbench --fpga_verilog_print_input_blif_testbench --fpga_verilog_include_timing --fpga_verilog_include_signal_init --fpga_verilog_print_modelsim_autodeck $modelsim_ini_file --fpga_verilog_print_formal_verification_top_netlist --fpga_verilog_print_autocheck_top_testbench $verilog_reference --fpga_verilog_print_user_defined_template --route_chan_width $vpr_route_chan_width --fpga_verilog_print_sdc_pnr --fpga_verilog_print_sdc_analysis --fpga_verilog_print_report_timing_tcl
 
-./vpr $arch_xml_file $blif_file --full_stats --nodisp --activity_file $act_file --fpga_verilog --fpga_verilog_dir $verilog_output_dirpath/$verilog_output_dirname\_compact --fpga_x2p_rename_illegal_port --fpga_bitstream_generator --fpga_verilog_print_top_testbench --fpga_verilog_print_input_blif_testbench --fpga_verilog_include_timing --fpga_verilog_include_signal_init --fpga_verilog_print_modelsim_autodeck $modelsim_ini_file --fpga_verilog_print_formal_verification_top_netlist --fpga_verilog_print_autocheck_top_testbench $verilog_reference --fpga_verilog_print_user_defined_template --route_chan_width $vpr_route_chan_width --fpga_x2p_compact_routing_hierarchy --fpga_verilog_print_sdc_pnr --fpga_verilog_print_sdc_analysis --fpga_verilog_print_report_timing_tcl
+#./vpr $arch_xml_file $blif_file --full_stats --nodisp --activity_file $act_file --fpga_verilog --fpga_verilog_dir $verilog_output_dirpath/$verilog_output_dirname\_compact --fpga_x2p_rename_illegal_port --fpga_bitstream_generator --fpga_verilog_print_top_testbench --fpga_verilog_print_input_blif_testbench --fpga_verilog_include_timing --fpga_verilog_include_signal_init --fpga_verilog_print_modelsim_autodeck $modelsim_ini_file --fpga_verilog_print_formal_verification_top_netlist --fpga_verilog_print_autocheck_top_testbench $verilog_reference --fpga_verilog_print_user_defined_template --route_chan_width $vpr_route_chan_width --fpga_x2p_compact_routing_hierarchy --fpga_verilog_print_sdc_pnr --fpga_verilog_print_sdc_analysis --fpga_verilog_print_report_timing_tcl