Oops. Don't forget to align single bb loops.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71363 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CodePlacementOpt.cpp b/lib/CodeGen/CodePlacementOpt.cpp
index 32399bf..77d23ee 100644
--- a/lib/CodeGen/CodePlacementOpt.cpp
+++ b/lib/CodeGen/CodePlacementOpt.cpp
@@ -248,7 +248,7 @@
   for (MachineBasicBlock::pred_iterator PI = MBB->pred_begin(),
          PE = MBB->pred_end(); PI != PE; ++PI) {
     MachineBasicBlock *PredMBB = *PI;
-    if (PredMBB->getNumber() > MBB->getNumber())
+    if (PredMBB == MBB || PredMBB->getNumber() > MBB->getNumber())
       return true;
   }
   return false;