[Mlir-commits] [mlir] [mlir][Vector] Update v.contract -> v.outerproduct tests (NFC) (PR #70449)

[Benjamin Maxwell]

================
@@ -1,15 +1,22 @@
 // RUN: mlir-opt %s --transform-interpreter --split-input-file | FileCheck %s
 
-#matmat_accesses = [
-  affine_map<(i, j, k) -> (i, k)>,
-  affine_map<(i, j, k) -> (k, j)>,
-  affine_map<(i, j, k) -> (i, j)>
-]
-#matmat_trait = {
-  indexing_maps = #matmat_accesses,
-  iterator_types = ["parallel", "parallel", "reduction"]
-}
+// NOTE - tests in this file are duplicated so that there's a version for
+//    * _fixed width_ and for _scalable_ vectors.
+// In order for the "vector.contract -> vector.outerproduct" patterns to work,
+// only the non-reduction dimension can be scalable (*). For Matmul operations
+// that is set to be the N dimension (i.e. rows of the output matrix), which
+// matches how matrix multiplication are normally implemented for e.g. 
+// Arm's SVE. However, making the M dimension scalable (i.e. columns of the
----------------
MacDue wrote:

nit:
```suggestion
// for Arm SVE. However, making the M dimension scalable (i.e. columns of the
```

https://github.com/llvm/llvm-project/pull/70449