nir/lower_subgroups: add lower_shuffle_to_swizzle_amd

masked_swizzle_amd can be much faster than shuffle.

Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5695>
2 files changed