diff --git a/source/reduce/change_operand_to_undef_reduction_opportunity.cpp b/source/reduce/change_operand_to_undef_reduction_opportunity.cpp
index 8e33da6..7cc06a0 100644
--- a/source/reduce/change_operand_to_undef_reduction_opportunity.cpp
+++ b/source/reduce/change_operand_to_undef_reduction_opportunity.cpp
@@ -35,6 +35,7 @@
   assert(operand_type_id);
   auto undef_id = FindOrCreateGlobalUndef(context_, operand_type_id);
   inst_->SetOperand(operand_index_, {undef_id});
+  context_->InvalidateAnalyses(opt::IRContext::kAnalysisDefUse);
 }
 
 }  // namespace reduce