presto-main/src/main/java/io/prestosql/operator/scalar/MathFunctions.java/MathFunctions/absFloat
class MathFunctions:    @Description("absolute value")
    @ScalarFunction("abs")
    @SqlType(StandardTypes.REAL)
    public static long absFloat(@SqlType(StandardTypes.REAL) long num)
    {
        return floatToRawIntBits(Math.abs(intBitsToFloat((int) num)));
    }