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

[Matthias Springer]

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matthias-springer wrote:

Can this be detected with visitor notifications? And then just invalidate the entire region. I can think of three situations how it can happen:

1. Entry block is erased. `notifyBlockErased` can detect this case.
2. A new block is inserted at the beginning of the region. `notifyBlockInserted` can detect this case.
3. An existing block is moved to the beginning of the region. Same as Case 2. This would also trigger a `notifyBlockInserted`.

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