[PATCH] D158849: [GVN] Invalidate MDA when deduplicating phi nodes

[Nikita Popov via Phabricator via llvm-commits]

nikic added inline comments.


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Comment at: llvm/test/Transforms/GVN/pr64598.ll:2
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 2
+; RUN: opt -S -passes=gvn < %s | FileCheck %s
+
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I got this test case by llvm-reducing between "good opt" and "bad opt", so I'm not sure how meaningful it is. I haven't pre-committed this test because address reuse might be flaky. 

I would have preferred to instead expose the issue by adding an `AssertingVH` in MemDepAnalysis. Unfortunately, the problematic value is part of `using ValueIsLoadPair = PointerIntPair<const Value *, 1, bool>` and there is no easy way to use AssertingVH in there (even if switching to std::pair, given how it is used).


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D158849/new/

https://reviews.llvm.org/D158849