fn submitComplete(ring: []u32, complete_tail: *Io.Batch.RingIndex, op: u32) void
fn submitComplete(ring: []u32, complete_tail: *Io.Batch.RingIndex, op: u32) void { const ct = complete_tail.*; const len: u31 = @intCast(ring.len); ring[ct.index(len)] = op; complete_tail.* = ct.next(len); }