presto-spi/src/main/java/io/prestosql/spi/block/RunLengthEncodedBlock.java/RunLengthEncodedBlock/getSlice
class RunLengthEncodedBlock:    @Override
    public Slice getSlice(int position, int offset, int length)
    {
        checkReadablePosition(position);
        return value.getSlice(0, offset, length);
    }