CodeGen: Fix a use-after-free in TailDuplication

The call to processPHI already erased MI from its parent, so MI isn't
even valid here, making the getParent() call a use-after-free in
addition to being redundant.

Found by ASan with the ArrayRecycler changes in llvm.org/pr26808.

llvm-svn: 266008

diff --git a/llvm/lib/CodeGen/TailDuplicator.cpp b/llvm/lib/CodeGen/TailDuplicator.cpp
index 7929d87..1ea15af 100644 (file)
--- a/llvm/lib/CodeGen/TailDuplicator.cpp
+++ b/llvm/lib/CodeGen/TailDuplicator.cpp
@@ -801,8 +801,6 @@ bool TailDuplicator::tailDuplicate(MachineFunction &MF, bool IsSimple,
         // from PredBB.
         MachineInstr *MI = &*I++;
         processPHI(MI, TailBB, PrevBB, LocalVRMap, CopyInfos, UsedByPhi, true);
-        if (MI->getParent())
-          MI->eraseFromParent();
       }
 
       // Now copy the non-PHI instructions.