From b3ca5ee0f10a8e8be5110b7c9d7fc7b46a316772 Mon Sep 17 00:00:00 2001
From: Anhijkt <mihail.ershov.zp@gmail.com>
Date: Wed, 13 Aug 2025 01:48:59 +0300
Subject: [PATCH] opt_dff: fix timeout issue

---
 passes/opt/opt_dff.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/passes/opt/opt_dff.cc b/passes/opt/opt_dff.cc
index 210c4828f..2fb0f947f 100644
--- a/passes/opt/opt_dff.cc
+++ b/passes/opt/opt_dff.cc
@@ -199,7 +199,7 @@ struct OptDffWorker
 
 					const auto complimentary_var = find_comp(left, right);
 
-					if (complimentary_var) {
+					if (complimentary_var && new_patterns.count(right)) {
 						new_patterns.erase(right);
 						right.erase(complimentary_var.value());
 						new_patterns.insert(right);