From b80ed8d15cf328e180319dafb433997a406b6b3e Mon Sep 17 00:00:00 2001
From: tangxifan <tangxifan@gmail.com>
Date: Thu, 4 Jul 2024 12:58:16 -0700
Subject: [PATCH] [core] fixed a bug

---
 openfpga/src/fabric/build_top_module_connection.cpp | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/openfpga/src/fabric/build_top_module_connection.cpp b/openfpga/src/fabric/build_top_module_connection.cpp
index 38b0491a9..2493c20c9 100644
--- a/openfpga/src/fabric/build_top_module_connection.cpp
+++ b/openfpga/src/fabric/build_top_module_connection.cpp
@@ -763,7 +763,10 @@ static void add_top_module_nets_connect_sb_and_cb(
       /* Only for the condition where cbs are on perimeter, the neighbour cb will be invalid
        * Bypass in such case on finding neighbour cbs
        */
-      if (instance_sb_coordinate.x() == device_rr_gsb.get_gsb_range().x() || instance_sb_coordinate.y() == 0) {
+      if (BOTTOM == side_manager.get_side() && instance_sb_coordinate.y() == 0) {
+        continue;
+      }
+      if (RIGHT == side_manager.get_side() && instance_sb_coordinate.x() == device_rr_gsb.get_gsb_range().x()) {
         continue;
       }
       const RRGSB& adjacent_gsb =