[PATCH] D33279: [JumpThreading] Dont RAUW condition incorrectly

[Anna Thomas via Phabricator via llvm-commits]

anna marked an inline comment as done.
anna added inline comments.


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Comment at: lib/Transforms/Scalar/JumpThreading.cpp:838
+        // exactly one value as returned by LVI. RAUW is incorrect in the
+        // presence of guards and assumes, that have the `Cond` as the use. This
+        // is because of circular logic where the value of `Cond` is calculated
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reames wrote:
> Er, I don't see why this is a circular logic bug?  I though the problem was that we were using a fact from the end of the block to reason about uses of the value before the assume/guard?
Yes. Bad phrasing on my part. This is *more* than a circular logic bug. I've updated the comment and add test cases to reflect that.


https://reviews.llvm.org/D33279