[PATCH] D62507: [Dominators] PR42041: Skip nullpointer successors

[Jakub Kuderski via Phabricator via llvm-commits]

kuhar requested changes to this revision.
kuhar added a comment.

Like I mentioned in another thread, I really dislike this approach. The single source of truth about graph traversal in dominators is the `ChildGetter` structure that internally uses `children` and `inverse_children`, and expects them to only return pointers to actual successors/predecessors. It's very weird that `children` and `inverse_children` return nullptrs -- they are not valid graph nodes, and I don't see why this would be desired, despite how unreachable regions are represented in the CFG.

Would it be possible to change some graph traits responsible for `children` and `inverse_children` instead? Or as an alternative, let clang CFG specialize `ChildGetter`? Right now I'm marking this revision with 'request changes', until we explore alternative approaches.


Repository:
  rL LLVM

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https://reviews.llvm.org/D62507