[PATCH] D110057: [LoopFlatten] Move it to a LoopPassManager

[Alina Sbirlea via Phabricator via llvm-commits]

asbirlea requested changes to this revision.
asbirlea added a comment.
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In D109958 <https://reviews.llvm.org/D109958> I missed the fact that LoopFlatten does not preserve any analyses. This is, I assume, the reason it was not added alongside other Loop passes before and probably also why I'm seeing a crash when adding it as part of LPM2.
The pass should not misbehave on its own in a LoopPassManager because it's not using the Updater to readd loops for reprocessing, otherwise it would be incorrect alone too.
So either LoopFlatten needs to be remain in it's own LPM or taught to preserve analyses (LoopInfo, DominatorTree, etc)


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D110057/new/

https://reviews.llvm.org/D110057