diff --git a/source/opt/optimizer.cpp b/source/opt/optimizer.cpp
index bc1441114..1ded2ee9b 100644
--- a/source/opt/optimizer.cpp
+++ b/source/opt/optimizer.cpp
@@ -161,6 +161,7 @@ Optimizer& Optimizer::RegisterPerformancePasses() {
       .RegisterPass(CreateDeadBranchElimPass())
       .RegisterPass(CreateMergeReturnPass())
       .RegisterPass(CreateInlineExhaustivePass())
+      .RegisterPass(CreateEliminateDeadFunctionsPass())
       .RegisterPass(CreateAggressiveDCEPass())
       .RegisterPass(CreatePrivateToLocalPass())
       .RegisterPass(CreateLocalSingleBlockLoadStoreElimPass())
diff --git a/test/tools/opt/flags.py b/test/tools/opt/flags.py
index f7dc64ce9..f8117d9dc 100644
--- a/test/tools/opt/flags.py
+++ b/test/tools/opt/flags.py
@@ -149,6 +149,7 @@ class TestPerformanceOptimizationPasses(expect.ValidObjectFile1_5,
       'eliminate-dead-branches',
       'merge-return',
       'inline-entry-points-exhaustive',
+      'eliminate-dead-functions',
       'eliminate-dead-code-aggressive',
       'private-to-local',
       'eliminate-local-single-block',