presto-orc/src/main/java/io/prestosql/orc/reader/FloatColumnReader.java/FloatColumnReader/readNullBlock
class FloatColumnReader:    private Block readNullBlock(boolean[] isNull, int nonNullCount)
            throws IOException
    {
        verifyNotNull(dataStream);
        int minNonNullValueSize = minNonNullValueSize(nonNullCount);
        if (nonNullValueTemp.length < minNonNullValueSize) {
            nonNullValueTemp = new int[minNonNullValueSize];
            systemMemoryContext.setBytes(sizeOf(nonNullValueTemp));
        }

        dataStream.next(nonNullValueTemp, nonNullCount);

        int[] result = ReaderUtils.unpackIntNulls(nonNullValueTemp, isNull);

        return new IntArrayBlock(isNull.length, Optional.of(isNull), result);
    }