Reenable tail duplication of bb with just an unconditional jump, but

don't remove blocks that have their address taken.

llvm-svn: 133659

1 files changed, 4 insertions, 4 deletions

diff --git a/llvm/lib/CodeGen/TailDuplication.cpp b/llvm/lib/CodeGen/TailDuplication.cpp
index d16369a4ca6..e5c23b36d29 100644
--- a/llvm/lib/CodeGen/TailDuplication.cpp
+++ b/llvm/lib/CodeGen/TailDuplication.cpp
@@ -207,7 +207,7 @@ bool TailDuplicatePass::TailDuplicateBlocks(MachineFunction &MF) {
       // TailBB's immediate successors are now successors of those predecessors
       // which duplicated TailBB. Add the predecessors as sources to the PHI
       // instructions.
-      bool isDead = MBB->pred_empty();
+      bool isDead = MBB->pred_empty() && !MBB->hasAddressTaken();
       if (PreRegAlloc)
         UpdateSuccessorsPHIs(MBB, isDead, TDBBs, Succs);
 
@@ -568,9 +568,9 @@ bool
 TailDuplicatePass::isSimpleBB(MachineBasicBlock *TailBB) {
   if (TailBB->succ_size() != 1)
     return false;
-  MachineBasicBlock::iterator I = TailBB->getFirstNonPHI();
+  MachineBasicBlock::iterator I = TailBB->begin();
   MachineBasicBlock::iterator E = TailBB->end();
-  while (I->isDebugValue() && I != E)
+  while (I != E && I->isDebugValue())
     ++I;
   if (I == E)
     return true;
@@ -712,7 +712,7 @@ TailDuplicatePass::TailDuplicate(MachineBasicBlock *TailBB, MachineFunction &MF,
   DenseSet<unsigned> UsedByPhi;
   getRegsUsedByPHIs(*TailBB, &UsedByPhi);
 
-  if (0 && isSimpleBB(TailBB))
+  if (isSimpleBB(TailBB))
     return duplicateSimpleBB(TailBB, TDBBs, UsedByPhi, Copies);
 
   // Iterate through all the unique predecessors and tail-duplicate this