[CodeGenPrepare] Try and appease sanitizers

dupRetToEnableTailCallOpts(BB) can invalidate BB. It must run *after* we iterate across BB!

llvm-svn: 257886
diff --git a/llvm/lib/CodeGen/CodeGenPrepare.cpp b/llvm/lib/CodeGen/CodeGenPrepare.cpp
index 4326ba9..dc1c298 100644
--- a/llvm/lib/CodeGen/CodeGenPrepare.cpp
+++ b/llvm/lib/CodeGen/CodeGenPrepare.cpp
@@ -5242,7 +5242,6 @@
     if (ModifiedDT)
       return true;
   }
-  MadeChange |= dupRetToEnableTailCallOpts(&BB);
 
   bool MadeBitReverse = true;
   while (TLI && MadeBitReverse) {
@@ -5254,6 +5253,7 @@
       }
     }
   }
+  MadeChange |= dupRetToEnableTailCallOpts(&BB);
   
   return MadeChange;
 }