presto-spi/src/main/java/io/prestosql/spi/block/RunLengthEncodedBlock.java/RunLengthEncodedBlock/getLoadedBlock
class RunLengthEncodedBlock:    @Override
    public Block getLoadedBlock()
    {
        Block loadedValueBlock = value.getLoadedBlock();

        if (loadedValueBlock == value) {
            return this;
        }
        return new RunLengthEncodedBlock(loadedValueBlock, positionCount);
    }