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└─⟦180fe333a⟧ Bits:30000405 8mm tape, Rational 1000, SW CATALOG, 10_20_0
└─⟦180fe333a⟧ Bits:30000537 8mm tape, Rational 1000, SW Catalog 10_20_0
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        └─⟦3b1ee7bd8⟧ 
            └─⟦this⟧ 

TextFile

with Instrument;
use Instrument;

---------------
-- Exhaustive case
---------------

-- This test evaluates the code efficiency of an exhaustive case statement,
-- i.e., one in which all case alternatives are explicitly specified.

-- The purpose of this test is to offer the compiler a case statement
-- that may be implemented by a single jump-table.

-- The variable Local is used in the case expression to select one of
-- five alternatives that are explicitly included in the case statement.
-- In the test version, each alternative comprises a camouflaged assign-
-- ment of the choice value to the global variable.  The value of the
-- case expression will always cause execution of the first case
-- alternative; however, this condition is carefully protected from
-- detection by the compiler so that no optimization of the case statement
-- is performed.

-- In the noise version, the case statement is removed to leave an
-- if-then-else construct comprising an equivalent number of assignments
-- so that the code efficiency metrics can be derived.

procedure Cseta2 is

    package New_Procs is new Procs (Integer);
    use New_Procs;

begin

    Start ("CSETA2", "Case Statement Exhaustive Test (test)");
    for I in 1 .. 10000 loop

        Let (Global, Ident (1));
        case Global is
            when 1 =>
                if Global = Ident (1) then
                    -- always true
                    Let (Global, Ident (1));
                else
                    Let (Global, Ident (0));
                end if;                             -- included in test version
            when 2 =>
                Let (Global, Ident (2));
            when 3 =>
                Let (Global, Ident (3));
            when 4 =>
                Let (Global, Ident (4));
            when 5 =>
                Let (Global, Ident (5));
            when others =>
                null;
                --    end if;                                -- included in control version
        end case;

    end loop;
    Stop;

end Cseta2;