pub fn fold_control(
cr: ClockReset,
input: ShaIn,
skid: FoldStage,
leaving: FoldStage,
out: ShaOut,
) -> FoldControlExpand description
The ring control, the same for every stage count. leaving is the state
leaving the last stage this cycle: it recirculates into stage 0 while it
has rounds left, and is added to its chaining value when it has done
round 79. A free slot takes the buffered block; the buffer takes the
client’s block when it is empty or being placed (ready).