Revert 131172 as it is causing clang to miscompile itself. I will try
to provide a reduced testcase.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131176 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/IfConversion.cpp b/lib/CodeGen/IfConversion.cpp
index 8b2c981..790200b 100644
--- a/lib/CodeGen/IfConversion.cpp
+++ b/lib/CodeGen/IfConversion.cpp
@@ -265,7 +265,7 @@
   if (!TII) return false;
 
   // Tail merge tend to expose more if-conversion opportunities.
-  BranchFolder BF(true, false);
+  BranchFolder BF(true);
   bool BFChange = BF.OptimizeFunction(MF, TII,
                                    MF.getTarget().getRegisterInfo(),
                                    getAnalysisIfAvailable<MachineModuleInfo>());
@@ -399,7 +399,7 @@
   BBAnalysis.clear();
 
   if (MadeChange && IfCvtBranchFold) {
-    BranchFolder BF(false, false);
+    BranchFolder BF(false);
     BF.OptimizeFunction(MF, TII,
                         MF.getTarget().getRegisterInfo(),
                         getAnalysisIfAvailable<MachineModuleInfo>());