func (r *Reader) execSeqs(data block, off int, litbuf []byte, seqCount int) error {
	// Set up the initial states for the sequence code readers.

	rbr, err := r.makeReverseBitReader(data, len(data)-1, off)
	if err != nil {
		return err
	}

	literalState, err := rbr.val(r.seqTableBits[seqLiteral])
	if err != nil {
		return err
	}