[PATCH] D31503: [GlobalISel]: Fix bug where we can report GISelFailure on erased instructions

[Ahmed Bougacha via Phabricator via llvm-commits]

ab accepted this revision.
ab added a comment.
This revision is now accepted and ready to land.

I'm not a big fan of this approach (because the iterative logic seems like it does belong in the helper), but it's mostly fine (we don't have users other than Legalizer), and it sounds like Tim and Quentin are on board. So, LGTM.

Can you add a test, say in arm64-fallback.ll?  I was able to hit the same problem with:

  define i16 @f(half* %p) {
    %tmp0 = load half, half* %p
    %tmp1 = fptoui half %tmp0 to i16
    ret i16 %tmp1
  }


https://reviews.llvm.org/D31503