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LIBRARY IEEE;

USE IEEE.STD_LOGIC_1164.ALL;

USE IEEE.numeric_std.ALL;

ENTITY logic IS

  GENERIC (

    w_data : NATURAL RANGE 1 TO 32 := 16);

  PORT (

    A  : IN  STD_LOGIC_VECTOR(w_data - 1 DOWNTO 0);

    B  : IN  STD_LOGIC_VECTOR(w_data - 1 DOWNTO 0);

    OP : IN  STD_LOGIC_VECTOR(2 DOWNTO 0);

    Y  : OUT STD_LOGIC_VECTOR(w_data - 1 DOWNTO 0));

END logic;

ARCHITECTURE Behavioral OF logic IS

  CONSTANT zero : STD_LOGIC_VECTOR(w_data - 1 DOWNTO 0) := (OTHERS => '0');

BEGIN  -- Behavioral

  WITH OP SELECT

    Y <=

    A       WHEN "000",

    NOT A   WHEN "001",

    A AND B WHEN "010",

    A OR B  WHEN "011",

    A XOR B WHEN "100",

    B       WHEN "101",

    zero    WHEN "110",

    zero    WHEN "111",

    zero    WHEN OTHERS;

END Behavioral;