[PATCH] D67366: [CGP] Ensure sinking multiple instructions does not invalidate dominance checks

[Dave Green via Phabricator via llvm-commits]

dmgreen marked an inline comment as done.
dmgreen added inline comments.


================
Comment at: llvm/lib/CodeGen/CodeGenPrepare.cpp:6206
 
-  SmallPtrSet<Instruction *, 4> MaybeDead;
+  SmallVector<Instruction *, 4> MaybeDead;
+  DenseMap<Instruction *, Instruction *> NewInstructions;
----------------
samparker wrote:
> So it's not possible for an instruction to be inserted multiple times?
Hmm. Yeah. Sinking the same instruction form multiple uses? It would be cloned more than once. I don't think anything currently uses it...

We do need to make sure they are deleted in a deterministic order. I can change it to a SetVector. Good suggestion, thanks!


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D67366/new/

https://reviews.llvm.org/D67366