diff --git a/SMPDataFlowAnalysis.cpp b/SMPDataFlowAnalysis.cpp
index 120b1c8b8cbd0e3a13efc6dcec702531af62e208..6f5605ac12f8a0c8f7c892b8136667e95632c943 100644
--- a/SMPDataFlowAnalysis.cpp
+++ b/SMPDataFlowAnalysis.cpp
@@ -645,7 +645,9 @@ void DefOrUseSet::Dump(void) {
 	return;
 }
 
-// Do all types agree, ignoring any flags registers in the set?
+// Do all types agree, ignoring any flags registers in the set? This is used
+//  for conditional move instructions; if all types agree, it does not matter
+//  whether the move happens or not.
 bool DefOrUseSet::TypesAgreeNoFlags(void) {
 	bool FoundFirstUse = false;
 	set<DefOrUse, LessDefUse>::iterator CurrUse;