1 files changed, 6 insertions, 0 deletions
diff --git a/llvm/lib/Passes/PassBuilder.cpp b/llvm/lib/Passes/PassBuilder.cpp
index 7235a885184..84301752853 100644
--- a/llvm/lib/Passes/PassBuilder.cpp
+++ b/llvm/lib/Passes/PassBuilder.cpp
@@ -132,6 +132,7 @@
 #include "llvm/Transforms/Scalar/SimpleLoopUnswitch.h"
 #include "llvm/Transforms/Scalar/SimplifyCFG.h"
 #include "llvm/Transforms/Scalar/Sink.h"
+#include "llvm/Transforms/Scalar/SpeculateAroundPHIs.h"
 #include "llvm/Transforms/Scalar/SpeculativeExecution.h"
 #include "llvm/Transforms/Scalar/TailRecursionElimination.h"
 #include "llvm/Transforms/Utils/AddDiscriminators.h"
@@ -799,6 +800,11 @@ PassBuilder::buildModuleOptimizationPipeline(OptimizationLevel Level,
   // resulted in single-entry-single-exit or empty blocks. Clean up the CFG.
   OptimizePM.addPass(SimplifyCFGPass());
 
+  // Optimize PHIs by speculating around them when profitable. Note that this
+  // pass needs to be run after any PRE or similar pass as it is essentially
+  // inserting redudnancies into the progrem. This even includes SimplifyCFG.
+  OptimizePM.addPass(SpeculateAroundPHIsPass());
+
   // Add the core optimizing pipeline.
   MPM.addPass(createModuleToFunctionPassAdaptor(std::move(OptimizePM)));