This revision adds vector transform operations that allow us to better inspect the composition
of various lowerings that were previously very opaque.
This commit is NFC in that it does not change patterns beyond adding `rewriter.notifyFailure` messages
and it does not change the tests beyond breaking them into pieces and using transforms instead of
throwaway opaque test passes.
Reviewed By: ftynse, springerm
Co-authored-by: Alex Zinenko <zinenko@google.com>
Differential Revision: https://reviews.llvm.org/D146755
Vector dialect patterns have grown enormously in the past year to a point where they are now impenetrable.
Start reorganizing them towards finer-grained control.
Differential Revision: https://reviews.llvm.org/D146736
