[PATCH] D118102: [LoopInterchange] Prevent interchange with unsafe control-flow divergence inside inner loops (PR48057)

[Michael Kruse via Phabricator via llvm-commits]

Meinersbur added a comment.

As mentioned in the LoopWG call, I don't think this has anything to do with dominance relations or diverging branches. Instead `store i16 %conv9.i, i16* @e` may be executed multiple times and the last written value written to `@e` must the value stored after the loop (the problem should occur even if the store is executed every time, i.e. not diverging). This is a classic output-dependency (write-after-write). I suggest to have a look at the dependency analysis and why it missed this case.


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https://reviews.llvm.org/D118102