Revert "[MBP] Reduce code size by running tail merging in MBP."

This reverts commit r271930, r271915, r271923.  They break a thumb selfhosting
bot.

llvm-svn: 272017
diff --git a/llvm/lib/CodeGen/BranchFolding.h b/llvm/lib/CodeGen/BranchFolding.h
index f704099..d759d53 100644
--- a/llvm/lib/CodeGen/BranchFolding.h
+++ b/llvm/lib/CodeGen/BranchFolding.h
@@ -20,24 +20,20 @@
   class MachineBranchProbabilityInfo;
   class MachineFunction;
   class MachineModuleInfo;
-  class MachineLoopInfo;
   class RegScavenger;
   class TargetInstrInfo;
   class TargetRegisterInfo;
 
   class LLVM_LIBRARY_VISIBILITY BranchFolder {
   public:
-    class MBFIWrapper;
-
     explicit BranchFolder(bool defaultEnableTailMerge, bool CommonHoist,
-                          MBFIWrapper &MBFI,
+                          const MachineBlockFrequencyInfo &MBFI,
                           const MachineBranchProbabilityInfo &MBPI);
 
-    bool OptimizeFunction(MachineFunction &MF, const TargetInstrInfo *tii,
-                          const TargetRegisterInfo *tri, MachineModuleInfo *mmi,
-                          MachineLoopInfo *mli = nullptr,
-                          bool AfterPlacement = false);
-
+    bool OptimizeFunction(MachineFunction &MF,
+                          const TargetInstrInfo *tii,
+                          const TargetRegisterInfo *tri,
+                          MachineModuleInfo *mmi);
   private:
     class MergePotentialsElt {
       unsigned Hash;
@@ -95,16 +91,13 @@
     };
     std::vector<SameTailElt> SameTails;
 
-    bool AfterBlockPlacement;
     bool EnableTailMerge;
     bool EnableHoistCommonCode;
     const TargetInstrInfo *TII;
     const TargetRegisterInfo *TRI;
     MachineModuleInfo *MMI;
-    MachineLoopInfo *MLI;
     RegScavenger *RS;
 
-  public:
     /// \brief This class keeps track of branch frequencies of newly created
     /// blocks and tail-merged blocks.
     class MBFIWrapper {
@@ -112,18 +105,13 @@
       MBFIWrapper(const MachineBlockFrequencyInfo &I) : MBFI(I) {}
       BlockFrequency getBlockFreq(const MachineBasicBlock *MBB) const;
       void setBlockFreq(const MachineBasicBlock *MBB, BlockFrequency F);
-      raw_ostream &printBlockFreq(raw_ostream &OS,
-                                  const MachineBasicBlock *MBB) const;
-      raw_ostream &printBlockFreq(raw_ostream &OS,
-                                  const BlockFrequency Freq) const;
 
     private:
       const MachineBlockFrequencyInfo &MBFI;
       DenseMap<const MachineBasicBlock *, BlockFrequency> MergedBBFreq;
     };
 
-  private:
-    MBFIWrapper &MBBFreqInfo;
+    MBFIWrapper MBBFreqInfo;
     const MachineBranchProbabilityInfo &MBPI;
 
     bool TailMergeBlocks(MachineFunction &MF);