[Mlir-commits] [mlir] [mlir] Avoid rewriting unreachable blocks in the greedy driver (PR #225814)

[Matthias Springer]

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matthias-springer wrote:

This is getting a bit complicated. I'm not sure if it would actually be much simpler, but have you considered erasing unreachable blocks directly after each pattern application?

This could take care of the case where an operation/block is moved into an unreachable IR segment. It would not matter anymore because that entire IR segment would be erased, including everything that was moved into it.

One downside of this approach is that only IR that becomes unreachable as part of the greedy rewrite can be detected based on listener notifications. Pre-existing unreachable IR would require a "cleanup" before the first pattern application.



https://github.com/llvm/llvm-project/pull/225814