ALUTest.vhd

LIBRARY ieee;
USE ieee.std_logic_1164.ALL;
 
-- Uncomment the following library declaration if using
-- arithmetic functions with Signed or Unsigned values
--USE ieee.numeric_std.ALL;
 
ENTITY ALUTest IS
END ALUTest;
 
ARCHITECTURE behavior OF ALUTest IS 
 
    -- Component Declaration for the Unit Under Test (UUT)
 
    COMPONENT ALU
    PORT(
         data1 : IN  std_logic_vector(31 downto 0);
         data2 : IN  std_logic_vector(31 downto 0);
         aluop : IN  std_logic_vector(3 downto 0);
         cin : IN  std_logic;
         dataout : OUT  std_logic_vector(31 downto 0);
         cflag : OUT  std_logic;
         zflag : OUT  std_logic;
         oflag : OUT  std_logic
        );
    END COMPONENT;
    

   --Inputs
   signal data1 : std_logic_vector(31 downto 0) := (others => '0');
   signal data2 : std_logic_vector(31 downto 0) := (others => '0');
   signal aluop : std_logic_vector(3 downto 0) := (others => '0');
   signal cin : std_logic := '0';

 	--Outputs
   signal dataout : std_logic_vector(31 downto 0);
   signal cflag : std_logic;
   signal zflag : std_logic;
   signal oflag : std_logic;
   -- No clocks detected in port list. Replace <clock> below with 
   -- appropriate port name 
 
   
BEGIN
 
	-- Instantiate the Unit Under Test (UUT)
   uut: ALU PORT MAP (
          data1 => data1,
          data2 => data2,
          aluop => aluop,
          cin => cin,
          dataout => dataout,
          cflag => cflag,
          zflag => zflag,
          oflag => oflag
        );

  
   -- Stimulus process
   stim_proc: process
   begin		
      -- hold reset state for 100 ns.
     		wait for 10ns;
		--AND testcase
			data1 <= "11000000000000000000000000000000" ;
			data2 <= "10100000000000000000000000000000" ;
			aluop <= "0000" ;
			wait for 10ns;
			report "Test1";
			assert(dataout = "10000000000000000000000000000000" and zflag = '0') report "1:Fail" severity error;

			wait for 1ns;
		
		--OR testcase
			data1 <= "11000000000000000000000000000000" ;
			data2 <= "10100000000000000000000000000000" ;
			aluop <= "0001" ;
			wait for 10ns;
			report "Test2";
			assert(dataout = "11100000000000000000000000000000" and zflag = '0') report "2:Fail" severity error;

			wait for 1ns;
		
		--ADD testcase1 (overflow = 1, cout = 0)
			data1 <= "01110000000000000000000000000000" ;
			data2 <= "01100000000000000000000000000000" ;
			aluop <= "0010" ;
			wait for 10ns;
			report "Test3";
			assert(dataout = "11010000000000000000000000000000" and oflag = '1' and cflag = '0' and zflag = '0') report "3:Fail" severity error;

			wait for 1ns;
		
		--ADD testcase2 (zero = 1, cout = 1)
			data1 <= "11110000000000000000000000000000" ;
			data2 <= "00010000000000000000000000000000" ;
			aluop <= "0010" ;
			wait for 10ns;
			report "Test4";
			assert(dataout = "00000000000000000000000000000000" and oflag = '0' and cflag = '1' and zflag = '1') report "4:Fail" severity error;

			wait for 1ns;

		--SUB testcase1 (cout = 1)
			data1 <= "00000000000000000000000000000111" ; --a = 7
			data2 <= "00000000000000000000000000000110" ; --b = 6
			cin <= '1' ;
			aluop <= "0110" ;
			wait for 10ns;
			report "Test5";
			assert(dataout = "00000000000000000000000000000001" and oflag = '0' and cflag = '1' and zflag = '0') report "5:Fail" severity error;

			wait for 1ns;

		--SUB testcase2 (cout = 0)
			data1 <= "00000000000000000000000000000110" ; --a = 6
			data2 <= "00000000000000000000000000000111" ; --b = 7
			cin <= '1' ;
			aluop <= "0110" ;
			wait for 10ns;
			report "Test6";
			assert(dataout = "11111111111111111111111111111111" and oflag = '0' and cflag = '0' and zflag = '0') report "6:Fail" severity error;

			wait for 1ns;

		--SUB testcase3 (overflow = 1)
			data1 <= "11111111111111111111111111111000" ; --a = -8
			data2 <= "00000000000000000000000000000001" ; --b = 1
			cin <= '1' ;
			aluop <= "0110" ;
			wait for 10ns;
			report "Test7";
			assert(dataout = "11111111111111111111111111110111" and oflag = '1' and cflag = '1' and zflag = '0') report "7:Fail" severity error;

			wait for 1ns;
			
		report "Test Complete";
      wait;
   end process;

END;