[Mlir-commits] [mlir] [mlir][ArmSME] Rewrite illegal `shape_casts` to `vector.transpose` ops (PR #82985)

[Cullen Rhodes]

c-rhodes wrote:

> ```mlir
> // Case 1:
> %a = vector.shape_cast %0 : vector<[4]x1xf32> to vector<1x[4]xf32>
...
> 
> Various lowerings and drop unit-dims patterns add such shape_casts, however, if they do not cancel out (which they likely won't if we've reached the vector-legalization pass) they will prevent lowering the IR.

something not clear to me here, `Case 1` would be introduced by `TransposeOpLowering` in `-convert-vector-to-llvm` and vector legalization is way before then? Or is the ordering slightly different in IREE?



https://github.com/llvm/llvm-project/pull/82985