-- THIS TEST EVALUATES THE CODE EFFICIENCY OF A LOOP STATEMENT WITH
-- THE FOR ITERATION SCHEME USING THE REVERSE OPTION.  THE LOOP IS
-- EXECUTED TWICE.

-- THE APPROACH USED IS SIMILAR TO THAT OF THE PRECEDING TEST (FOR-LOOP
-- 2 ITERATIONS), BUT THE COMPILER MAY BE ABLE TO TAKE ADVANTAGE OF SPEC
-- MACHINE INSTRUCTIONS FOR EFFICIENTLY DECREMENTING THE LOOP PARAMETER.

with Instrument;
use Instrument;
with Ics;
use Ics;
procedure Fl2ra2 is

    N : Integer;
    M : Integer;

begin
    Start ("FL2RA2", " EFFICIENCY OF LOOP STMT, USING FOR, 2 ITERATIONS " &
                        "1000 REPETITIONS");

    for Lcv in 1 .. 1000 loop
        N := Ident (Zero);
        M := Ident (One);

        for I in reverse N .. M loop
            -- EXECUTED TWICE
            Let (Global, Ident (One));
        end loop;

        -- SINCE THE LOOP BODY IS EXECUTED TWICE IN THE TEST VERSION, AND TH
        -- VERSION MUST CONTAIN THE SAME AMOUNT OF CODE BUT EXECUTE THE SAME
        -- STATEMENTS (OTHER THAN THE LOOP STATEMENT), A CONDITIONAL STATEME
        -- WHOSE TRUE PART DIFFERS IN THE NOISE VERSION IS USED.

        Let (Global, N);
        Let (Global, M);
        if Global /= Zero then
            -- ALWAYS TRUE
            Let (Global, Ident (One));
        else
            -- COMMENTED OUT IN NOISE VERSIO
            Let (Global, Ident (One));                -- EXECUTED IN NOISE VERSI
            --ELSE                                -- COMMENTED OUT IN TEST VERSION
            Let (Global, Ident (One));
        end if;
    end loop;

    Stop;

end Fl2ra2;