[NVPTX] Blacklist TailDuplicate pass

This causes issues with virtual registers.  We will likely need
to fix TailDuplicate in the future, or introduce a new version
that plays nicely with vregs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194373 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/NVPTX/NVPTXTargetMachine.cpp

@@ -126,6 +126,7 @@ void NVPTXPassConfig::addIRPasses() {
   disablePass(&PrologEpilogCodeInserterID);
   disablePass(&MachineCopyPropagationID);
   disablePass(&BranchFolderPassID);
+  disablePass(&TailDuplicateID);
 
   TargetPassConfig::addIRPasses();
   addPass(createGenericToNVVMPass());