I added more select-to-shift folds to DAGCombiner in:
rL374397
rL374555
...and noticed that AArch64 does not override a TLI hook that was added with:
rL296977
Not sure if that is intentional or oversight, so I flipped the setting completely and updated some auto-generated regression tests. It's not a universal win, but likely worth doing? If so, there are a few more regression tests that need updating/inspection.
I don't intend to do more with this patch, so feel free to commandeer/close.