[PATCH] D118558: [IVDescriptors] Support FOR where we have multiple sink pointed

[Florian Hahn via Phabricator via llvm-commits]

fhahn added reviewers: Ayal, spatel.
fhahn added a comment.

Thanks for the patch, response inline.



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Comment at: llvm/lib/Analysis/IVDescriptors.cpp:932
+        return true;
+    }
 
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I think this handles the case where Previous doesn't come before LastPrev incorrectly. I added an additional test that crashes with the current version of the patch (02ee3fbff816).

To start with, you should be able to use `return Previous->comesBefore(LastPrev);` here. The reasoning is that if Previous comes before LastPrev, `SinkCandidate` already gets sunk after `Previous`, so there's nothing to do here.

I put up a follow-up patch (D118642), that should handle the other case correctly.


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