[PATCH] D44676: [SCEV] Make exact taken count calculation more optimistic

[Florian Hahn via Phabricator via llvm-commits]

fhahn added inline comments.


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Comment at: lib/Analysis/ScalarEvolution.cpp:6673
+  // All exits we have collected must dominate the only latch.
+  if (!Latch)
+    return SE->getCouldNotCompute();
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Another thing to double check. Are you sure we only compute exit counts when we have a single loop latch that dominates all exiting nodes? I had a quick look but could not find the place where we ensure that (computeBackedgeTakenCount states that the loop latch may be null). In that case we might miss a case when all exit counts are equal.



https://reviews.llvm.org/D44676