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Diffstat (limited to 'testsuite/vests/vhdl-93/ashenden/compliant/ch_09_fg_09_02.vhd')
-rw-r--r-- | testsuite/vests/vhdl-93/ashenden/compliant/ch_09_fg_09_02.vhd | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/testsuite/vests/vhdl-93/ashenden/compliant/ch_09_fg_09_02.vhd b/testsuite/vests/vhdl-93/ashenden/compliant/ch_09_fg_09_02.vhd new file mode 100644 index 000000000..1bcc30cd4 --- /dev/null +++ b/testsuite/vests/vhdl-93/ashenden/compliant/ch_09_fg_09_02.vhd @@ -0,0 +1,95 @@ + +-- 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_09_fg_09_02.vhd,v 1.2 2001-10-26 16:29:34 paw Exp $ +-- $Revision: 1.2 $ +-- +-- --------------------------------------------------------------------- + +package fg_09_02_a is + + -- code from book (in text) + + function "+" ( bv1, bv2 : bit_vector ) return bit_vector; + + -- end code from book + +end package fg_09_02_a; + + + +package body fg_09_02_a is + + -- code from book + + function "+" ( bv1, bv2 : bit_vector ) return bit_vector is + + alias norm1 : bit_vector(1 to bv1'length) is bv1; + alias norm2 : bit_vector(1 to bv2'length) is bv2; + + variable result : bit_vector(1 to bv1'length); + variable carry : bit := '0'; + + begin + if bv1'length /= bv2'length then + report "arguments of different length" severity failure; + else + for index in norm1'reverse_range loop + result(index) := norm1(index) xor norm2(index) xor carry; + carry := ( norm1(index) and norm2(index) ) + or ( carry and ( norm1(index) or norm2(index) ) ); + end loop; + end if; + return result; + end function "+"; + + -- end code from book + +end package body fg_09_02_a; + + + + +entity fg_09_02_b is +end entity fg_09_02_b; + + +architecture test of fg_09_02_b is + + use work.fg_09_02_a.all; + +begin + + stimulus : process is + use std.textio.all; + variable L : line; + begin + write(L, X"0002" + X"0000"); + writeline(output, L); + write(L, X"0002" + X"0005"); + writeline(output, L); + write(L, X"0002" + X"FFFE"); + writeline(output, L); + + wait; + end process stimulus; + +end architecture test; |