Revert "Implemented suggested changes"

This reverts commit f2dd02c.

Author: mikhailramalho

llvm/include/llvm/CodeGen/TargetPassConfig.h

@@ -457,7 +457,7 @@ class TargetPassConfig : public ImmutablePass {
 
   /// Add a CodeGen pass at this point in the pipeline after checking overrides.
   /// Return the pass that was added, or zero if no pass was added.
-  AnalysisID addPass(IdentifyingPassPtr PassID);
+  AnalysisID addPass(AnalysisID PassID);
 
   /// Add a pass to the PassManager if that pass is supposed to be run, as
   /// determined by the StartAfter and StopAfter options. Takes ownership of the

llvm/lib/CodeGen/TargetPassConfig.cpp

@@ -745,9 +745,7 @@ void TargetPassConfig::addPass(Pass *P) {
 ///
 /// addPass cannot return a pointer to the pass instance because is internal the
 /// PassManager and the instance we create here may already be freed.
-AnalysisID TargetPassConfig::addPass(IdentifyingPassPtr PassPtr) {
-  AnalysisID PassID = PassPtr.isInstance() ? PassPtr.getInstance()->getPassID()
-                                           : PassPtr.getID();
+AnalysisID TargetPassConfig::addPass(AnalysisID PassID) {
   IdentifyingPassPtr TargetID = getPassSubstitution(PassID);
   IdentifyingPassPtr FinalPtr = overridePass(PassID, TargetID);
   if (!FinalPtr.isValid())
@@ -1515,7 +1513,8 @@ void TargetPassConfig::addMachineLateOptimization() {
   // Cleanup of redundant immediate/address loads.
   addPass(&MachineLateInstrsCleanupID);
 
-  addPass(IdentifyingPassPtr(createBranchFolderPass(getEnableTailMerge())));
+  // Branch folding must be run after regalloc and prolog/epilog insertion.
+  addPass(createBranchFolderPass(getEnableTailMerge()));
 
   // Tail duplication.
   // Note that duplicating tail just increases code size and degrades