----------------------------------------------------------------------------                                                                      ---- Copyright (c) 1990,1991,1992 by Synopsys, Inc.  All rights reserved. ----                                                                      ---- This source file may be used and distributed without restriction     ---- provided that this copyright statement is not removed from the file  ---- and that any derivative work contains this copyright notice.         ----                                                                      ----	Package name: STD_LOGIC_ARITH					----									----	Purpose: 							----	 A set of arithemtic, conversion, and comparison functions 	----	 for SIGNED, UNSIGNED, SMALL_INT, INTEGER, 			----	 STD_ULOGIC, STD_LOGIC, and STD_LOGIC_VECTOR.			----									----------------------------------------------------------------------------library IEEE;use IEEE.std_logic_1164.all;package std_logic_arith is    type UNSIGNED is array (NATURAL range <>) of STD_LOGIC;    type SIGNED is array (NATURAL range <>) of STD_LOGIC;    subtype SMALL_INT is INTEGER range 0 to 1;    function "+"(L: UNSIGNED; R: UNSIGNED) return UNSIGNED;    function "+"(L: SIGNED; R: SIGNED) return SIGNED;    function "+"(L: UNSIGNED; R: SIGNED) return SIGNED;    function "+"(L: SIGNED; R: UNSIGNED) return SIGNED;    function "+"(L: UNSIGNED; R: INTEGER) return UNSIGNED;    function "+"(L: INTEGER; R: UNSIGNED) return UNSIGNED;    function "+"(L: SIGNED; R: INTEGER) return SIGNED;    function "+"(L: INTEGER; R: SIGNED) return SIGNED;    function "+"(L: UNSIGNED; R: STD_ULOGIC) return UNSIGNED;    function "+"(L: STD_ULOGIC; R: UNSIGNED) return UNSIGNED;    function "+"(L: SIGNED; R: STD_ULOGIC) return SIGNED;    function "+"(L: STD_ULOGIC; R: SIGNED) return SIGNED;    function "+"(L: UNSIGNED; R: UNSIGNED) return STD_LOGIC_VECTOR;    function "+"(L: SIGNED; R: SIGNED) return STD_LOGIC_VECTOR;    function "+"(L: UNSIGNED; R: SIGNED) return STD_LOGIC_VECTOR;    function "+"(L: SIGNED; R: UNSIGNED) return STD_LOGIC_VECTOR;    function "+"(L: UNSIGNED; R: INTEGER) return STD_LOGIC_VECTOR;    function "+"(L: INTEGER; R: UNSIGNED) return STD_LOGIC_VECTOR;    function "+"(L: SIGNED; R: INTEGER) return STD_LOGIC_VECTOR;    function "+"(L: INTEGER; R: SIGNED) return STD_LOGIC_VECTOR;    function "+"(L: UNSIGNED; R: STD_ULOGIC) return STD_LOGIC_VECTOR;    function "+"(L: STD_ULOGIC; R: UNSIGNED) return STD_LOGIC_VECTOR;    function "+"(L: SIGNED; R: STD_ULOGIC) return STD_LOGIC_VECTOR;    function "+"(L: STD_ULOGIC; R: SIGNED) return STD_LOGIC_VECTOR;    function "-"(L: UNSIGNED; R: UNSIGNED) return UNSIGNED;    function "-"(L: SIGNED; R: SIGNED) return SIGNED;    function "-"(L: UNSIGNED; R: SIGNED) return SIGNED;    function "-"(L: SIGNED; R: UNSIGNED) return SIGNED;    function "-"(L: UNSIGNED; R: INTEGER) return UNSIGNED;    function "-"(L: INTEGER; R: UNSIGNED) return UNSIGNED;    function "-"(L: SIGNED; R: INTEGER) return SIGNED;    function "-"(L: INTEGER; R: SIGNED) return SIGNED;    function "-"(L: UNSIGNED; R: STD_ULOGIC) return UNSIGNED;    function "-"(L: STD_ULOGIC; R: UNSIGNED) return UNSIGNED;    function "-"(L: SIGNED; R: STD_ULOGIC) return SIGNED;    function "-"(L: STD_ULOGIC; R: SIGNED) return SIGNED;    function "-"(L: UNSIGNED; R: UNSIGNED) return STD_LOGIC_VECTOR;    function "-"(L: SIGNED; R: SIGNED) return STD_LOGIC_VECTOR;    function "-"(L: UNSIGNED; R: SIGNED) return STD_LOGIC_VECTOR;    function "-"(L: SIGNED; R: UNSIGNED) return STD_LOGIC_VECTOR;    function "-"(L: UNSIGNED; R: INTEGER) return STD_LOGIC_VECTOR;    function "-"(L: INTEGER; R: UNSIGNED) return STD_LOGIC_VECTOR;    function "-"(L: SIGNED; R: INTEGER) return STD_LOGIC_VECTOR;    function "-"(L: INTEGER; R: SIGNED) return STD_LOGIC_VECTOR;    function "-"(L: UNSIGNED; R: STD_ULOGIC) return STD_LOGIC_VECTOR;    function "-"(L: STD_ULOGIC; R: UNSIGNED) return STD_LOGIC_VECTOR;    function "-"(L: SIGNED; R: STD_ULOGIC) return STD_LOGIC_VECTOR;    function "-"(L: STD_ULOGIC; R: SIGNED) return STD_LOGIC_VECTOR;    function "+"(L: UNSIGNED) return UNSIGNED;    function "+"(L: SIGNED) return SIGNED;    function "-"(L: SIGNED) return SIGNED;    function "ABS"(L: SIGNED) return SIGNED;    function "+"(L: UNSIGNED) return STD_LOGIC_VECTOR;    function "+"(L: SIGNED) return STD_LOGIC_VECTOR;    function "-"(L: SIGNED) return STD_LOGIC_VECTOR;    function "ABS"(L: SIGNED) return STD_LOGIC_VECTOR;    function "*"(L: UNSIGNED; R: UNSIGNED) return UNSIGNED;    function "*"(L: SIGNED; R: SIGNED) return SIGNED;    function "*"(L: SIGNED; R: UNSIGNED) return SIGNED;    function "*"(L: UNSIGNED; R: SIGNED) return SIGNED;    function "*"(L: UNSIGNED; R: UNSIGNED) return STD_LOGIC_VECTOR;    function "*"(L: SIGNED; R: SIGNED) return STD_LOGIC_VECTOR;    function "*"(L: SIGNED; R: UNSIGNED) return STD_LOGIC_VECTOR;    function "*"(L: UNSIGNED; R: SIGNED) return STD_LOGIC_VECTOR;    function "<"(L: UNSIGNED; R: UNSIGNED) return BOOLEAN;    function "<"(L: SIGNED; R: SIGNED) return BOOLEAN;    function "<"(L: UNSIGNED; R: SIGNED) return BOOLEAN;    function "<"(L: SIGNED; R: UNSIGNED) return BOOLEAN;    function "<"(L: UNSIGNED; R: INTEGER) return BOOLEAN;    function "<"(L: INTEGER; R: UNSIGNED) return BOOLEAN;    function "<"(L: SIGNED; R: INTEGER) return BOOLEAN;    function "<"(L: INTEGER; R: SIGNED) return BOOLEAN;    function "<="(L: UNSIGNED; R: UNSIGNED) return BOOLEAN;    function "<="(L: SIGNED; R: SIGNED) return BOOLEAN;    function "<="(L: UNSIGNED; R: SIGNED) return BOOLEAN;    function "<="(L: SIGNED; R: UNSIGNED) return BOOLEAN;    function "<="(L: UNSIGNED; R: INTEGER) return BOOLEAN;    function "<="(L: INTEGER; R: UNSIGNED) return BOOLEAN;    function "<="(L: SIGNED; R: INTEGER) return BOOLEAN;    function "<="(L: INTEGER; R: SIGNED) return BOOLEAN;    function ">"(L: UNSIGNED; R: UNSIGNED) return BOOLEAN;    function ">"(L: SIGNED; R: SIGNED) return BOOLEAN;    function ">"(L: UNSIGNED; R: SIGNED) return BOOLEAN;    function ">"(L: SIGNED; R: UNSIGNED) return BOOLEAN;    function ">"(L: UNSIGNED; R: INTEGER) return BOOLEAN;    function ">"(L: INTEGER; R: UNSIGNED) return BOOLEAN;    function ">"(L: SIGNED; R: INTEGER) return BOOLEAN;    function ">"(L: INTEGER; R: SIGNED) return BOOLEAN;    function ">="(L: UNSIGNED; R: UNSIGNED) return BOOLEAN;    function ">="(L: SIGNED; R: SIGNED) return BOOLEAN;    function ">="(L: UNSIGNED; R: SIGNED) return BOOLEAN;    function ">="(L: SIGNED; R: UNSIGNED) return BOOLEAN;    function ">="(L: UNSIGNED; R: INTEGER) return BOOLEAN;    function ">="(L: INTEGER; R: UNSIGNED) return BOOLEAN;    function ">="(L: SIGNED; R: INTEGER) return BOOLEAN;    function ">="(L: INTEGER; R: SIGNED) return BOOLEAN;    function "="(L: UNSIGNED; R: UNSIGNED) return BOOLEAN;    function "="(L: SIGNED; R: SIGNED) return BOOLEAN;    function "="(L: UNSIGNED; R: SIGNED) return BOOLEAN;    function "="(L: SIGNED; R: UNSIGNED) return BOOLEAN;    function "="(L: UNSIGNED; R: INTEGER) return BOOLEAN;    function "="(L: INTEGER; R: UNSIGNED) return BOOLEAN;    function "="(L: SIGNED; R: INTEGER) return BOOLEAN;    function "="(L: INTEGER; R: SIGNED) return BOOLEAN;    function "/="(L: UNSIGNED; R: UNSIGNED) return BOOLEAN;    function "/="(L: SIGNED; R: SIGNED) return BOOLEAN;    function "/="(L: UNSIGNED; R: SIGNED) return BOOLEAN;    function "/="(L: SIGNED; R: UNSIGNED) return BOOLEAN;    function "/="(L: UNSIGNED; R: INTEGER) return BOOLEAN;    function "/="(L: INTEGER; R: UNSIGNED) return BOOLEAN;    function "/="(L: SIGNED; R: INTEGER) return BOOLEAN;    function "/="(L: INTEGER; R: SIGNED) return BOOLEAN;    function SHL(ARG: UNSIGNED; COUNT: UNSIGNED) return UNSIGNED;    function SHL(ARG: SIGNED; COUNT: UNSIGNED) return SIGNED;    function SHR(ARG: UNSIGNED; COUNT: UNSIGNED) return UNSIGNED;    function SHR(ARG: SIGNED; COUNT: UNSIGNED) return SIGNED;    function CONV_INTEGER(ARG: INTEGER) return INTEGER;    function CONV_INTEGER(ARG: UNSIGNED) return INTEGER;    function CONV_INTEGER(ARG: SIGNED) return INTEGER;    function CONV_INTEGER(ARG: STD_ULOGIC) return SMALL_INT;    function CONV_UNSIGNED(ARG: INTEGER; SIZE: INTEGER) return UNSIGNED;    function CONV_UNSIGNED(ARG: UNSIGNED; SIZE: INTEGER) return UNSIGNED;    function CONV_UNSIGNED(ARG: SIGNED; SIZE: INTEGER) return UNSIGNED;    function CONV_UNSIGNED(ARG: STD_ULOGIC; SIZE: INTEGER) return UNSIGNED;    function CONV_SIGNED(ARG: INTEGER; SIZE: INTEGER) return SIGNED;    function CONV_SIGNED(ARG: UNSIGNED; SIZE: INTEGER) return SIGNED;    function CONV_SIGNED(ARG: SIGNED; SIZE: INTEGER) return SIGNED;    function CONV_SIGNED(ARG: STD_ULOGIC; SIZE: INTEGER) return SIGNED;    function CONV_STD_LOGIC_VECTOR(ARG: INTEGER; SIZE: INTEGER) 						       return STD_LOGIC_VECTOR;    function CONV_STD_LOGIC_VECTOR(ARG: UNSIGNED; SIZE: INTEGER) 						       return STD_LOGIC_VECTOR;    function CONV_STD_LOGIC_VECTOR(ARG: SIGNED; SIZE: INTEGER) 						       return STD_LOGIC_VECTOR;    function CONV_STD_LOGIC_VECTOR(ARG: STD_ULOGIC; SIZE: INTEGER) 						       return STD_LOGIC_VECTOR;    -- zero extend STD_LOGIC_VECTOR (ARG) to SIZE,     -- SIZE < 0 is same as SIZE = 0    -- returns STD_LOGIC_VECTOR(SIZE-1 downto 0)    function EXT(ARG: STD_LOGIC_VECTOR; SIZE: INTEGER) return STD_LOGIC_VECTOR;    -- sign extend STD_LOGIC_VECTOR (ARG) to SIZE,     -- SIZE < 0 is same as SIZE = 0    -- return STD_LOGIC_VECTOR(SIZE-1 downto 0)    function SXT(ARG: STD_LOGIC_VECTOR; SIZE: INTEGER) return STD_LOGIC_VECTOR;end Std_logic_arith;library IEEE;use IEEE.std_logic_1164.all;package body std_logic_arith is    function max(L, R: INTEGER) return INTEGER is    begin	if L > R then	    return L;	else	    return R;	end if;    end;    function min(L, R: INTEGER) return INTEGER is    begin	if L < R then	    return L;	else	    return R;	end if;    end;    -- synopsys synthesis_off    type tbl_type is array (STD_ULOGIC) of STD_ULOGIC;    constant tbl_BINARY : tbl_type :=	('X', 'X', '0', '1', 'X', 'X', '0', '1', 'X');    -- synopsys synthesis_on    -- synopsys synthesis_off    type tbl_mvl9_boolean is array (STD_ULOGIC) of boolean;    constant IS_X : tbl_mvl9_boolean :=        (true, true, false, false, true, true, false, false, true);    -- synopsys synthesis_on    function MAKE_BINARY(A : STD_ULOGIC) return STD_ULOGIC is	-- synopsys built_in SYN_FEED_THRU    begin	-- synopsys synthesis_off	    if (IS_X(A)) then		assert false 		report "There is an 'U'|'X'|'W'|'Z'|'-' in an arithmetic operand, the result will be 'X'(es)."		severity warning;	        return ('X');	    end if;	    return tbl_BINARY(A);	-- synopsys synthesis_on    end;    function MAKE_BINARY(A : UNSIGNED) return UNSIGNED is	-- synopsys built_in SYN_FEED_THRU	variable one_bit : STD_ULOGIC;	variable result : UNSIGNED (A'range);    begin	-- synopsys synthesis_off	    for i in A'range loop	        if (IS_X(A(i))) then		    assert false 		    report "There is an 'U'|'X'|'W'|'Z'|'-' in an arithmetic operand, the result will be 'X'(es)."		    severity warning;		    result := (others => 'X');	            return result;	        end if;		result(i) := tbl_BINARY(A(i));	    end loop;	    return result;	-- synopsys synthesis_on    end;    function MAKE_BINARY(A : UNSIGNED) return SIGNED is	-- synopsys built_in SYN_FEED_THRU	variable one_bit : STD_ULOGIC;	variable result : SIGNED (A'range);    begin	-- synopsys synthesis_off	    for i in A'range loop	        if (IS_X(A(i))) then		    assert false 		    report "There is an 'U'|'X'|'W'|'Z'|'-' in an arithmetic operand, the result will be 'X'(es)."		    severity warning;		    result := (others => 'X');	            return result;	        end if;		result(i) := tbl_BINARY(A(i));	    end loop;	    return result;	-- synopsys synthesis_on    end;    function MAKE_BINARY(A : SIGNED) return UNSIGNED is	-- synopsys built_in SYN_FEED_THRU	variable one_bit : STD_ULOGIC;	variable result : UNSIGNED (A'range);    begin	-- synopsys synthesis_off	    for i in A'range loop	        if (IS_X(A(i))) then		    assert false 		    report "There is an 'U'|'X'|'W'|'Z'|'-' in an arithmetic operand, the result will be 'X'(es)."		    severity warning;		    result := (others => 'X');	            return result;	        end if;		result(i) := tbl_BINARY(A(i));	    end loop;	    return result;	-- synopsys synthesis_on    end;    function MAKE_BINARY(A : SIGNED) return SIGNED is	-- synopsys built_in SYN_FEED_THRU	variable one_bit : STD_ULOGIC;	variable result : SIGNED (A'range);    begin	-- synopsys synthesis_off	    for i in A'range loop	        if (IS_X(A(i))) then		    assert false 		    report "There is an 'U'|'X'|'W'|'Z'|'-' in an arithmetic operand, the result will be 'X'(es)."		    severity warning;		    result := (others => 'X');	            return result;	        end if;		result(i) := tbl_BINARY(A(i));	    end loop;	    return result;	-- synopsys synthesis_on    end;    function MAKE_BINARY(A : STD_LOGIC_VECTOR) return STD_LOGIC_VECTOR is	-- synopsys built_in SYN_FEED_THRU	variable one_bit : STD_ULOGIC;	variable result : STD_LOGIC_VECTOR (A'range);    begin	-- synopsys synthesis_off	    for i in A'range loop	        if (IS_X(A(i))) then		    assert false 		    report "There is an 'U'|'X'|'W'|'Z'|'-' in an arithmetic operand, the result will be 'X'(es)."		    severity warning;		    result := (others => 'X');	            return result;	        end if;		result(i) := tbl_BINARY(A(i));	    end loop;	    return result;	-- synopsys synthesis_on    end;    function MAKE_BINARY(A : UNSIGNED) return STD_LOGIC_VECTOR is	-- synopsys built_in SYN_FEED_THRU	variable one_bit : STD_ULOGIC;	variable result : STD_LOGIC_VECTOR (A'range);    begin	-- synopsys synthesis_off	    for i in A'range loop	        if (IS_X(A(i))) then		    assert false 		    report "There is an 'U'|'X'|'W'|'Z'|'-' in an arithmetic operand, the result will be 'X'(es)."		    severity warning;		    result := (others => 'X');	            return result;	        end if;		result(i) := tbl_BINARY(A(i));	    end loop;	    return result;	-- synopsys synthesis_on    end;    function MAKE_BINARY(A : SIGNED) return STD_LOGIC_VECTOR is	-- synopsys built_in SYN_FEED_THRU	variable one_bit : STD_ULOGIC;	variable result : STD_LOGIC_VECTOR (A'range);    begin	-- synopsys synthesis_off	    for i in A'range loop	        if (IS_X(A(i))) then		    assert false 		    report "There is an 'U'|'X'|'W'|'Z'|'-' in an arithmetic operand, the result will be 'X'(es)."		    severity warning;		    result := (others => 'X');	            return result;	        end if;		result(i) := tbl_BINARY(A(i));	    end loop;	    return result;	-- synopsys synthesis_on    end;    -- Type propagation function which returns a signed type with the    -- size of the left arg.    function LEFT_SIGNED_ARG(A,B: SIGNED) return SIGNED is      variable Z: SIGNED (A'left downto 0);      -- pragma return_port_name Z    begin      return(Z);    end;	    -- Type propagation function which returns an unsigned type with the    -- size of the left arg.    function LEFT_UNSIGNED_ARG(A,B: UNSIGNED) return UNSIGNED is      variable Z: UNSIGNED (A'left downto 0);      -- pragma return_port_name Z    begin      return(Z);    end;	    -- Type propagation function which returns a signed type with the    -- size of the result of a signed multiplication    function MULT_SIGNED_ARG(A,B: SIGNED) return SIGNED is      variable Z: SIGNED ((A'length+B'length-1) downto 0);      -- pragma return_port_name Z    begin      return(Z);    end;	    -- Type propagation function which returns an unsigned type with the    -- size of the result of a unsigned multiplication    function MULT_UNSIGNED_ARG(A,B: UNSIGNED) return UNSIGNED is      variable Z: UNSIGNED ((A'length+B'length-1) downto 0);      -- pragma return_port_name Z    begin      return(Z);    end;    function mult(A,B: SIGNED) return SIGNED is      variable BA: SIGNED((A'length+B'length-1) downto 0);      variable PA: SIGNED((A'length+B'length-1) downto 0);      variable AA: SIGNED(A'length downto 0);      variable neg: STD_ULOGIC;      constant one : UNSIGNED(1 downto 0) := "01";            -- pragma map_to_operator MULT_TC_OP      -- pragma type_function MULT_SIGNED_ARG      -- pragma return_port_name Z      begin	if (A(A'left) = 'X' or B(B'left) = 'X') then            PA := (others => 'X');            return(PA);	end if;        PA := (others => '0');