Just used to work around a bug in an old libavcodec encoder version.
Don't optimize them.
-tpel_mc_func {put,avg}_tpel_pixels_tab
- Used only for SVQ3, so only optimize them if you need fast SVQ3 decoding.
-
add_bytes/diff_bytes
For huffyuv only, optimize if you want a faster ffhuffyuv codec.