[Mlir-commits] [mlir] [mlir][memref] Add a new `ReifyResultShapes` pass (PR #145927)

[Nicolas Vasilache]

nicolasvasilache wrote:

> This is my source of confusion. As far as I know this is meant to extract information about the shape of the result of the, but this is actually changing the operation itself. This seems like something that cannot be done just based on the interface/clone. The change in the result type might make the operation invalid (according to its verifier). This kind of rewrite cannot really be done just on the interface.

As usual, confluence is a non-negotiable property for the system to avoid crumbling upon its own weight. 
Otherwise we have a flawed design with undocumented internal assumption of when it is or isn't safe to use.
What I am hearing is there are confluence issues with ReifyRankedShapedTypeOpInterface wrt various op verifiers, making ReifyRankedShapedTypeOpInterface unsafe to use?

When I look [here](https://github.com/llvm/llvm-project/commit/092372da15e5165be14cdbb7cac3cf4976fd82d0#diff-8cc8879b3d74154e46c94a24f4f1650e9233547350fc425092f8317ba63a6b62L55) I see  an alteration of the interface that seems related to confluence.
Why was the assertion removed in this case?

https://github.com/llvm/llvm-project/pull/145927