Is there a GoTo ?

In this function I have to GOTO to a label1, but GOTO keyword is not
working, can you please help me in getting the way from which I am able to
jump from a particular code to label.
Thanks...

CREATE OR REPLACE FUNCTION test(i integer) RETURNS integer AS
$$BEGINIF i<0 THEN RETURN i + 1;ELSE
GOTO label1;END IF<<label1>>RETURN null;END;$$ LANGUAGE plpgsql;