[PATCH] D107645: [GlobalDCE] Handle relative pointers in VFE (for Swift vtables)

Fri Aug 27 12:03:16 PDT 2021

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

LGTM, thanks for splitting this off.

Please wait a couple of days with committing, in case there are additional comments/concerns.

================
Comment at: llvm/lib/Analysis/TypeMetadataUtils.cpp:196
+      if (Operand1TargetGlobal != TopLevelGlobal)
+        return nullptr;
+
----------------
kubamracek wrote:
> fhahn wrote:
> > Could you also add a test case for that?
> That's tough without <https://reviews.llvm.org/D108741>, because returning "not found" from this function is currently going to make GlobalDCE be *more aggressive* and remove that slot from the vtable. Writing a test for this behavior is... "weird" because that behavior sounds like a bug (to be fixed with <https://reviews.llvm.org/D108741>).
It would still provide coverage for that code path.

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D107645/new/

https://reviews.llvm.org/D107645