From 69d8c1386a239372a2ab8910bf12d5d70701b7fa Mon Sep 17 00:00:00 2001
From: Eddie Hung <eddie@fpgeh.com>
Date: Fri, 6 Dec 2019 16:21:06 -0800
Subject: [PATCH] Do not connect undriven POs to 1'bx

---
 frontends/aiger/aigerparse.cc | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/frontends/aiger/aigerparse.cc b/frontends/aiger/aigerparse.cc
index 9374f1ab3..084107b35 100644
--- a/frontends/aiger/aigerparse.cc
+++ b/frontends/aiger/aigerparse.cc
@@ -1005,15 +1005,10 @@ void AigerReader::post_process()
 			if (other_wire) {
 				other_wire->port_input = false;
 				other_wire->port_output = false;
-			}
-			if (wire->port_input) {
-				if (other_wire)
+				if (wire->port_input)
 					module->connect(other_wire, SigSpec(wire, i));
-			}
-			else {
-								  // Since we skip POs that are connected to Sx,
-								  // re-connect them here
-				module->connect(SigSpec(wire, i), other_wire ? other_wire : SigSpec(RTLIL::Sx));
+				else
+					module->connect(SigSpec(wire, i), other_wire);
 			}
 		}
 	}