faster plpgsql in PostgreSQL 9.5 (second part)

Tom Lane introduced new state for TOAST types - expanded state. The side effect of this change together with some changes in plpgsql internals has big impact to speed of array operation in plpgsql.
I have two plpgsql block with cycles. First enforces a array fields update, second a array append.

DO $$ 
DECLARE a int[] = array_fill(10, ARRAY[10000]);
BEGIN
FOR i IN 1 .. 10000 LOOP
  a[i] := 0;
END LOOP;
END;
$$;

DO $$ 
DECLARE a int[] = '{}';
BEGIN
FOR i IN 1 .. 10000 LOOP
  a := a || 10;
END LOOP;
END;
$$;

You can try this code on PostgreSQL 9.4 - and you can get time 450 and 220ms. Same code needs 6 and 5 ms only on PostgreSQL 9.5! It is more than one order speedup.