[PATCH] D144057: [GVN] permit GVN of non-local loads for ASAN unless undef is produced

[Nikita Popov via Phabricator via llvm-commits]

nikic requested changes to this revision.
nikic added a comment.
This revision now requires changes to proceed.

I don't think this is right as implemented. Imagine you have `if (...) { store v, p } x = load p`. GVN would convert this to something like `x = phi(v, undef)`. With asan, we want this to report if the if is not taken. However, I believe that your checks will permit the transform, because the load folding result is not literally undef (but is still undef on one path).


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https://reviews.llvm.org/D144057