diff --git a/llvm/tools/gccas/gccas.cpp b/llvm/tools/gccas/gccas.cpp
index 896b79a02209..fae4ddb205ac 100644
--- a/llvm/tools/gccas/gccas.cpp
+++ b/llvm/tools/gccas/gccas.cpp
@@ -95,6 +95,7 @@ void AddConfiguredTransformationPasses(PassManager &PM) {
 
   if (!DisableInline)
     addPass(PM, createFunctionInliningPass());   // Inline small functions
+  addPass(PM, createSimplifyLibCallsPass());     // Library Call Optimizations
   addPass(PM, createArgumentPromotionPass());    // Scalarize uninlined fn args
 
   addPass(PM, createRaisePointerReferencesPass());// Recover type information