PL/SQL: NVL vs Coalesce - 2

gistfile1.sql

alter session set plsql_optimize_level=0;

declare 
   i integer; 
   a number :=1; 
   b number :=1; 

   l integer:=dbms_utility.get_time();

   procedure print(v in varchar2) is
   begin
      dbms_output.put_line(to_char((dbms_utility.get_time-l)/100,'0999.99')||' '||v);
      l:=dbms_utility.get_time();
   end;
   
begin 
      print('Start');

      for i in 1..1e7 loop 
         a:=nvl(b,i); 
      end loop; 
      print('NVL');
      
      for i in 1..1e7 loop 
         a:=coalesce(b,i); 
      end loop; 
      print('Coalesce');
      
end;
/