diff --git a/source/opt/optimizer.cpp b/source/opt/optimizer.cpp
index b72bd3c21..500af8989 100644
--- a/source/opt/optimizer.cpp
+++ b/source/opt/optimizer.cpp
@@ -140,6 +140,7 @@ Optimizer& Optimizer::RegisterPerformancePasses() {
   return RegisterPass(CreateMergeReturnPass())
       .RegisterPass(CreateInlineExhaustivePass())
       .RegisterPass(CreateAggressiveDCEPass())
+      .RegisterPass(CreatePrivateToLocalPass())
       .RegisterPass(CreateLocalSingleBlockLoadStoreElimPass())
       .RegisterPass(CreateLocalSingleStoreElimPass())
       .RegisterPass(CreateAggressiveDCEPass())
@@ -175,6 +176,7 @@ Optimizer& Optimizer::RegisterSizePasses() {
   return RegisterPass(CreateMergeReturnPass())
       .RegisterPass(CreateInlineExhaustivePass())
       .RegisterPass(CreateAggressiveDCEPass())
+      .RegisterPass(CreatePrivateToLocalPass())
       .RegisterPass(CreateScalarReplacementPass())
       .RegisterPass(CreateLocalAccessChainConvertPass())
       .RegisterPass(CreateLocalSingleBlockLoadStoreElimPass())