[AArch64] Enable global merge pass.

llvm-svn: 206861

1 files changed, 9 insertions, 0 deletions

diff --git a/llvm/lib/Target/AArch64/AArch64TargetMachine.cpp b/llvm/lib/Target/AArch64/AArch64TargetMachine.cpp
index d9c990d7d56..844e8ab2195 100644
--- a/llvm/lib/Target/AArch64/AArch64TargetMachine.cpp
+++ b/llvm/lib/Target/AArch64/AArch64TargetMachine.cpp
@@ -19,6 +19,7 @@
 #include "llvm/CodeGen/Passes.h"
 #include "llvm/PassManager.h"
 #include "llvm/Support/TargetRegistry.h"
+#include "llvm/Transforms/Scalar.h"
 
 using namespace llvm;
 
@@ -86,11 +87,19 @@ public:
     return *getAArch64TargetMachine().getSubtargetImpl();
   }
 
+  bool addPreISel() override;
   virtual bool addInstSelector();
   virtual bool addPreEmitPass();
 };
 } // namespace
 
+bool AArch64PassConfig::addPreISel() {
+  if (TM->getOptLevel() != CodeGenOpt::None)
+    addPass(createGlobalMergePass(TM));
+
+  return false;
+}
+
 TargetPassConfig *AArch64TargetMachine::createPassConfig(PassManagerBase &PM) {
   return new AArch64PassConfig(this, PM);
 }