presto-spi/src/main/java/io/prestosql/spi/type/RealType.java/RealType/compareTo
class RealType:    @Override
    public int compareTo(Block leftBlock, int leftPosition, Block rightBlock, int rightPosition)
    {
        // WARNING: the correctness of InCodeGenerator is dependent on the implementation of this
        // function being the equivalence of internal long representation.
        float leftValue = intBitsToFloat(leftBlock.getInt(leftPosition, 0));
        float rightValue = intBitsToFloat(rightBlock.getInt(rightPosition, 0));
        return Float.compare(leftValue, rightValue);
    }