[PATCH] D102615: [LoopDeletion] Break backedge if we can prove that the loop is exited on 1st iteration (try 3)

[Max Kazantsev via Phabricator via llvm-commits]

mkazantsev added inline comments.


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Comment at: llvm/lib/Transforms/Scalar/LoopDeletion.cpp:302
+        if (DT.dominates(Incoming, BB->getTerminator()))
+          FirstIterValue[&PN] =
+              getValueOnFirstIteration(Incoming, FirstIterValue, SQ);
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nikic wrote:
> This acquired a reference to `FirstIterValue[&PN]`, then calls `getValueOnFirstIteration()` which may invalidate it and then writes to it.
Wow, that's fishy! Thanks!


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D102615/new/

https://reviews.llvm.org/D102615