[Mlir-commits] [mlir] [mlir][XeGPU] Add optional layout attribute to LoadGather StoreScatter ops (PR #163414)

[Charitha Saumya]

https://github.com/charithaintc commented:

I think there is some confusion about how layout utils work. maybe worth having a meeting on this?

Here is a summary of my understanding.

Before layout propagation: All the anchor ops must have valid layouts (permanent). this is the only requirement.
After Layout propagation: All anchor ops have layouts (permanent). Plus all vector op results should have valid layouts with `layout_result_{}` attribute notation.

Before any pass that consume layouts: Layouts are forward propagated to op operands from the defining results. After this all ops will have `layout_operand_{}` attributes as well in addition to above. (This is done in Subgroup distribution already but not in other passes, so be careful when writing/modifying tests)

This whole thing has some redundancy which could be optimized. but this is the current status for now. 


https://github.com/llvm/llvm-project/pull/163414