From c0b302d719b3f2553e27ed5f57c45573789764ca Mon Sep 17 00:00:00 2001
From: Dan <46821332+nsadeveloper789@users.noreply.github.com>
Date: Thu, 20 Apr 2023 15:52:01 -0400
Subject: [PATCH] GP-3312: Fix IllegalArgumentException when emulating
 backwards.

---
 .../listing/AbstractBaseDBTraceDefinedUnitsView.java         | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/Ghidra/Debug/Framework-TraceModeling/src/main/java/ghidra/trace/database/listing/AbstractBaseDBTraceDefinedUnitsView.java b/Ghidra/Debug/Framework-TraceModeling/src/main/java/ghidra/trace/database/listing/AbstractBaseDBTraceDefinedUnitsView.java
index a54ddf2b05..c0e65045d9 100644
--- a/Ghidra/Debug/Framework-TraceModeling/src/main/java/ghidra/trace/database/listing/AbstractBaseDBTraceDefinedUnitsView.java
+++ b/Ghidra/Debug/Framework-TraceModeling/src/main/java/ghidra/trace/database/listing/AbstractBaseDBTraceDefinedUnitsView.java
@@ -376,8 +376,11 @@ public abstract class AbstractBaseDBTraceDefinedUnitsView<T extends AbstractDBTr
 		if (extending == null) {
 			toScan = span;
 		}
+		else if (span.lmax() <= extending.getEndSnap()) {
+			// we're shrinking or staying the same, so not possible to collide with others
+			return span;
+		}
 		else {
-			assert span.lmax() > extending.getEndSnap();
 			toScan = span.withMin(extending.getEndSnap() + 1);
 		}
 		T truncateBy =