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-- Copyright (C) 1996 Morgan Kaufmann Publishers, Inc
-- This file is part of VESTs (Vhdl tESTs).
-- VESTs is free software; you can redistribute it and/or modify it
-- under the terms of the GNU General Public License as published by the
-- Free Software Foundation; either version 2 of the License, or (at
-- your option) any later version.
-- VESTs is distributed in the hope that it will be useful, but WITHOUT
-- ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
-- FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
-- for more details.
-- You should have received a copy of the GNU General Public License
-- along with VESTs; if not, write to the Free Software Foundation,
-- Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
-- ---------------------------------------------------------------------
--
-- $Id: ch_08_fg_08_08.vhd,v 1.3 2001-10-26 16:29:34 paw Exp $
-- $Revision: 1.3 $
--
-- ---------------------------------------------------------------------
package bit_vector_signed_arithmetic is
function "+" ( bv1, bv2 : bit_vector ) return bit_vector;
function "-" ( bv : bit_vector ) return bit_vector;
function "*" ( bv1, bv2 : bit_vector ) return bit_vector;
-- . . .
end package bit_vector_signed_arithmetic;
-- not in book
library bv_utilities;
use bv_utilities.bv_arithmetic;
-- end not in book
package body bit_vector_signed_arithmetic is
function "+" ( bv1, bv2 : bit_vector ) return bit_vector is -- . . .
-- not in book
begin
return bv_arithmetic."+"(bv1, bv2);
end function "+";
-- end not in book
function "-" ( bv : bit_vector ) return bit_vector is -- . . .
-- not in book
begin
return bv_arithmetic."-"(bv);
end function "-";
-- end not in book
function mult_unsigned ( bv1, bv2 : bit_vector ) return bit_vector is
-- . . .
begin
-- not in book
-- . . .
return bv_arithmetic.bv_multu(bv1, bv2);
-- end not in book
end function mult_unsigned;
function "*" ( bv1, bv2 : bit_vector ) return bit_vector is
begin
if bv1(bv1'left) = '0' and bv2(bv2'left) = '0' then
return mult_unsigned(bv1, bv2);
elsif bv1(bv1'left) = '0' and bv2(bv2'left) = '1' then
return -mult_unsigned(bv1, -bv2);
elsif bv1(bv1'left) = '1' and bv2(bv2'left) = '0' then
return -mult_unsigned(-bv1, bv2);
else
return mult_unsigned(-bv1, -bv2);
end if;
end function "*";
-- . . .
end package body bit_vector_signed_arithmetic;
-- not in book
entity fg_08_08 is
end entity fg_08_08;
library bv_utilities;
use bv_utilities.bit_vector_signed_arithmetic.all;
use std.textio.all;
architecture test of fg_08_08 is
begin
stimulus : process is
variable L : line;
begin
write(L, X"0002" + X"0005");
writeline(output, L);
write(L, X"0002" + X"FFFE");
writeline(output, L);
write(L, - X"0005");
writeline(output, L);
write(L, - X"FFFE");
writeline(output, L);
write(L, X"0002" * X"0005");
writeline(output, L);
write(L, X"0002" * X"FFFD");
writeline(output, L);
wait;
end process stimulus;
end architecture test;
-- end not in book
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