The horizontal parts of Armv8.0 Neon 6-tap HV subpel filters can be further improved by some pointer arithmetic and saving some EXT instructions in their data rearrangement codes.
Relative runtime of micro benchmarks after this patch on some Cortex CPU cores:
HBD mct hv X1 A78 A76 A72 A55
regular w8: 0.952x 0.989x 0.924x 0.973x 0.976x
regular w16: 0.961x 0.993x 0.928x 0.952x 0.971x
regular w32: 0.964x 0.996x 0.930x 0.973x 0.972x
regular w64: 0.963x 0.997x 0.930x 0.969x 0.974xVideoLAN code repository instance