[PATCH] D90529: Allow nonnull attribute to accept poison

Sat Dec 12 11:32:54 PST 2020

aqjune added a comment.

I'll make this patch include the updates in the `align` attribute first because it helps making fewer patches.
The next patch (operand bundle) will include changes in `nonnull`/`align` operand bundles as well.

In D90529#2449703 <https://reviews.llvm.org/D90529#2449703>, @nlopes wrote:

> For the partial undef memory access example that Juneyoung gave.. Well, maybe we need to make it UB to dereference a non-deterministic value. Doesn't seem like it's a very useful thing to do, and this non-determinism comes from some previous undefined behavior, so it seems fine to just make dereference of partial undef UB. Simplifies things.

There was a discussion for this: https://groups.google.com/g/llvm-dev/c/2Qk4fOHUoAE/m/OxZa3bIhAgAJ
This partially undef thing is a bit painful.. :/

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D90529/new/

https://reviews.llvm.org/D90529