Extracts the relevant dimensions from the map under test to build up the
maps to test against in a permutation-invariant way.
This also includes a fix to the indexing maps used by
isColumnMajorMatmul. The maps as currently written do not describe a
column-major matmul. The linalg named op column_major_matmul has the
correct maps (and notably fails the current test).
If `C = matmul(A, B)` we want an operation that given A in column major
format and B in column major format produces C in column major format.
Given that for a matrix, faux column major is just transpose.
`column_major_matmul(transpose(A), transpose(B)) = transpose(C)`. If
`A` is `NxK` and `B` is `KxM`, then `C` is `NxM`, so `transpose(A)` is
`KxN`, `transpose(B)` is `MxK` and `transpose(C)` is `MxN`, not `NxM`
as these maps currently have.
Reviewed By: nicolasvasilache
Differential Revision: https://reviews.llvm.org/D96984
Geoffrey Martin-Noble