[Mlir-commits] [mlir] [mlir][scf] Fix `for-loop-peeling` crash (PR #77697)

[Felix Schneider]

ubfx wrote:

> Unrelated to this bugfix, but invalid step probably shouldn't cause verification failure, as it can appears as folding result in unreachable branches.

Good point, how could this be done with the `PoisonAttr` instead?

> Can you also add test for negative step, which is also invalid?

Done!

https://github.com/llvm/llvm-project/pull/77697