--***************************************************************************
-- VHDL BIT_VECTOR Operations for MVL7 type
--
-- Copyright (c) 1990 UCI CADLAB, Dept. of ICS
-- Author : Sanjiv Narayan (narayan@ics.uci.edu)
--
-- Updated 7/8/91 by Sanjiv and Frank
--
-- updated by Champaka Ramachandran 16/10/92
--
--***************************************************************************
use work.TYPES.all;
package MVL7_functions is
function WiredOne (V: MVL7_VECTOR) return MVL7;
function SHL( v2 : MVL7_VECTOR ; fill : MVL7 ) return MVL7_VECTOR;
function SHL0( v2 : MVL7_VECTOR ; dist : INTEGER ) return MVL7_VECTOR;
function SHL1( v2 : MVL7_VECTOR ; dist : INTEGER ) return MVL7_VECTOR;
function SHR( v2 : MVL7_VECTOR ; fill : MVL7 ) return MVL7_VECTOR;
function SHR0( v2 : MVL7_VECTOR ; dist : INTEGER ) return MVL7_VECTOR;
function SHR1( v2 : MVL7_VECTOR ; dist : INTEGER ) return MVL7_VECTOR;
function ROTR( v2 : MVL7_VECTOR ; dist : INTEGER ) return MVL7_VECTOR;
function ROTL( v2 : MVL7_VECTOR ; dist : INTEGER ) return MVL7_VECTOR;
function I2B( Number : integer ; len : integer ) return MVL7_VECTOR;
function B2I( v2 : MVL7_VECTOR ) return integer;
function COMP( v2 : MVL7_VECTOR ) return MVL7_VECTOR;
function TWOs_COMP( v2 : MVL7_VECTOR ) return MVL7_VECTOR;
function ODD_PARITY( v1 : MVL7_VECTOR ) return MVL7;
function EVEN_PARITY( v1 : MVL7_VECTOR ) return MVL7;
function REVERSE( v2 : MVL7_VECTOR ) return MVL7_VECTOR;
function SUM( v2 : MVL7_VECTOR ) return integer;
function PAD( v : MVL7_VECTOR ; width : integer ) return MVL7_VECTOR;
function DEC( x : MVL7_VECTOR ) return MVL7_VECTOR;
function INC( x : MVL7_VECTOR ) return MVL7_VECTOR;
function CARRY_ADD( x1 : MVL7_VECTOR ; x2 : MVL7_VECTOR ) return MVL7_VECTOR;
function "+" ( x1 : MVL7_VECTOR ; x2 : MVL7_VECTOR ) return MVL7_VECTOR;
function "-"( x1 : MVL7_VECTOR ; x2 : MVL7_VECTOR ) return MVL7_VECTOR;
function "*" ( x1 : MVL7_VECTOR ; x2 : MVL7_VECTOR ) return MVL7_VECTOR;
-- truth table for "WiredOr" function
constant tbl_WIREDOR: MVL7_TABLE :=
-- -----------------------------------------------
-- | X 0 1 Z W L H | |
-- -----------------------------------------------
(('X', 'X', '1', 'X', 'X', 'L', 'H'), -- | X |
('X', '0', '1', '0', '0', 'L', 'H'), -- | 0 |
('1', '1', '1', '1', '1', '1', '1'), -- | 1 |
('X', '0', '1', 'Z', 'W', 'L', 'H'), -- | Z |
('X', '0', '1', 'W', 'W', 'W', 'W'), -- | W |
('L', 'L', '1', 'L', 'W', 'L', 'W'), -- | L |
('H', 'H', '1', 'H', 'W', 'W', 'H')); -- | H |
function WiredOr (V: MVL7_VECTOR) return MVL7;
end;
package body MVL7_functions is
--***************************************************************************
function WiredOne (V: MVL7_VECTOR) return MVL7 is
variable result: MVL7 := 'Z';
variable got_one: MVL7 := '0';
begin
for i in V'range loop
next when V(i) = 'Z';
if (got_one = '1') then
-- assert false
-- report
-- "Multiple contributors to WiredSingle node."
-- severity warning;
result := 'X';
return result;
end if;
got_one := '1';
result := V(i);
end loop;
return result;
end WiredOne;
--***************************************************************************
function SHL( v2 : MVL7_VECTOR ; fill : MVL7 ) return MVL7_VECTOR is
variable v1: MVL7_VECTOR (v2'high downto v2'low);
variable shift_val: MVL7_VECTOR (v1'high downto v1'low);
variable I: integer;
begin
v1 := v2;
for I in v1'high downto (v1'low + 1) loop
shift_val(I) := v1(I - 1);
end loop ;
shift_val(v1'low) := fill;
return shift_val;
end;
--***************************************************************************
function SHL0( v2 : MVL7_VECTOR ; dist : INTEGER ) return MVL7_VECTOR is
variable v1: MVL7_VECTOR (v2'high downto v2'low);
variable I: INTEGER;
begin
v1 := v2;
for I in 1 to dist loop
v1 := SHL(v1,'0');
end loop ;
return v1;
end;
--***************************************************************************
function SHL1( v2 : MVL7_VECTOR ; dist : INTEGER ) return MVL7_VECTOR is
variable v1: MVL7_VECTOR (v2'high downto v2'low);
variable I: INTEGER;
begin
v1 := v2;
for I in 1 to dist loop
v1 := SHL(v1,'1');
end loop ;
return v1;
end;
--***************************************************************************
function SHR( v2 : MVL7_VECTOR ; fill : MVL7 ) return MVL7_VECTOR is
variable v1: MVL7_VECTOR (v2'high downto v2'low);
variable shift_val: MVL7_VECTOR (v1'high downto v1'low);
begin
v1 := v2;
for I in v1'low to (v1'high - 1) loop
shift_val(I) := v1(I + 1);
end loop ;
shift_val(v1'high) := fill;
return shift_val;
end;
--***************************************************************************
function SHR0( v2 : MVL7_VECTOR ; dist : INTEGER ) return MVL7_VECTOR is
variable v1: MVL7_VECTOR (v2'high downto v2'low);
variable I: INTEGER;
begin
v1 := v2;
for I in 1 to dist loop
v1 := SHR(v1,'0');
end loop ;
return v1;
end;
--***************************************************************************
function SHR1( v2 : MVL7_VECTOR ; dist : INTEGER ) return MVL7_VECTOR is
variable v1: MVL7_VECTOR (v2'high downto v2'low);
variable I: INTEGER;
begin
v1 := v2;
for I in 1 to dist loop
v1 := SHR(v1,'1');
end loop ;
return v1;
end;
--***************************************************************************
function ROTR( v2 : MVL7_VECTOR ; dist : INTEGER ) return MVL7_VECTOR is
variable v1: MVL7_VECTOR (v2'high downto v2'low);
variable I: INTEGER;
begin
v1 := v2;
for i in 1 to dist loop
v1 := SHR(v1,v1(v1'low));
end loop ;
return v1;
end;
--***************************************************************************
function ROTL( v2 : MVL7_VECTOR ; dist : INTEGER ) return MVL7_VECTOR is
variable v1: MVL7_VECTOR (v2'high downto v2'low);
variable I: INTEGER;
begin
v1 := v2;
for i in 1 to dist loop
v1 := SHL(v1,v1(v1'high));
end loop ;
return v1;
end;
--***************************************************************************
function I2B( Number : integer ; len : integer ) return MVL7_VECTOR is
variable temp: MVL7_VECTOR (len - 1 downto 0);
variable NUM: integer:=0;
variable QUOTIENT: integer:=0;
begin
QUOTIENT := Number;
for I in 0 to len - 1 loop
NUM := 0;
while QUOTIENT > 1 loop
QUOTIENT := QUOTIENT - 2;
NUM := NUM + 1;
end loop ;
case QUOTIENT is
when 1 =>
temp(I) := '1';
when 0 =>
temp(I) := '0';
when others =>
null;
end case;
QUOTIENT := NUM;
end loop ;
return temp;
end;
--***************************************************************************
function B2I( v2 : MVL7_VECTOR ) return integer is
variable v1: MVL7_VECTOR (v2'high downto v2'low);
variable SUM: integer:=0;
begin
v1 := v2;
for N in v1'low to v1'high loop
if v1(N) = '1' then
SUM := SUM + (2 ** (N - v1'low));
end if;
end loop ;
return SUM;
end;
--***************************************************************************
function COMP( v2 : MVL7_VECTOR ) return MVL7_VECTOR is
variable v1: MVL7_VECTOR (v2'high downto v2'low);
variable temp: MVL7_VECTOR (v1'high downto v1'low);
variable I: INTEGER;
begin
v1 := v2;
for I in v1'low to v1'high loop
if v1(I) = '0' then
temp(i) := '1';
else
temp(i) := '0';
end if;
end loop ;
return temp;
end;
--***************************************************************************
function TWOs_COMP( v2 : MVL7_VECTOR ) return MVL7_VECTOR is
variable v1: MVL7_VECTOR (v2'high downto v2'low);
variable temp: MVL7_VECTOR (v1'high downto v1'low);
begin
v1 := v2;
temp := comp(v1);
temp := INC(temp);
return temp;
end;
--***************************************************************************
function "-" ( x1 : MVL7_VECTOR ; x2 : MVL7_VECTOR ) return MVL7_VECTOR is
variable v1: MVL7_VECTOR (x1'high - x1'low downto 0);
variable v2: MVL7_VECTOR (x2'high - x2'low downto 0);
variable SUM: MVL7_VECTOR (v1'high downto v1'low);
begin
v1 := x1;
v2 := x2;
assert v1'length = v2'length
report "MVL7 vector -: operands of unequal lengths" severity FAILURE;
SUM := I2B(B2I(v1) - B2I(v2),SUM'length);
return (SUM);
end;
--***************************************************************************
function DEC( x : MVL7_VECTOR ) return MVL7_VECTOR is
variable v: MVL7_VECTOR (x'high downto x'low);
begin
v := x;
return I2B(B2I(v) - 1,v'length);
end;
--***************************************************************************
function CARRY_ADD( x1: MVL7_VECTOR ; x2: MVL7_VECTOR ) return MVL7_VECTOR is
variable v1: MVL7_VECTOR (x1'high - x1'low downto 0);
variable v2: MVL7_VECTOR (x2'high - x2'low downto 0);
variable SUM: MVL7_VECTOR (x1'high - x1'low + 1 downto 0);
-- + 1 is for carry
begin
v1 := x1;
v2 := x2;
assert v1'length = v2'length
report "MVL7vector carry add:operands of unequal lengths"
severity FAILURE;
SUM := I2B(B2I(v1) + B2I(v2),SUM'length);
return (SUM);
end;
--***************************************************************************
function "+" ( x1 : MVL7_VECTOR ; x2 : MVL7_VECTOR ) return MVL7_VECTOR is
variable v1: MVL7_VECTOR (x1'high - x1'low downto 0);
variable v2: MVL7_VECTOR (x2'high - x2'low downto 0);
variable SUM: MVL7_VECTOR (v1'high downto v1'low);
begin
v1 := x1;
v2 := x2;
assert v1'length = v2'length
report "MVL7 vector +: operands of unequal lengths" severity FAILURE;
SUM := I2B(B2I(v1) + B2I(v2),SUM'length);
return (SUM);
end;
--***************************************************************************
function INC( x : MVL7_VECTOR ) return MVL7_VECTOR is
variable v: MVL7_VECTOR (x'high downto x'low);
begin
v := x;
return I2B(B2I(v) + 1,v'length);
end;
--***************************************************************************
function ODD_PARITY( v1 : MVL7_VECTOR ) return MVL7 is
begin
if ((SUM(v1) mod 2) = 1) then
return '0';
else
return '1';
end if;
end;
--***************************************************************************
function EVEN_PARITY( v1 : MVL7_VECTOR ) return MVL7 is
begin
if ((SUM(v1) mod 2) = 1) then
return '1';
else
return '0';
end if;
end;
--***************************************************************************
function REVERSE( v2 : MVL7_VECTOR ) return MVL7_VECTOR is
variable v1: MVL7_VECTOR (v2'high downto v2'low);
variable temp: MVL7_VECTOR (v1'high downto v1'low);
begin
v1 := v2;
for I in v1'high downto v1'low loop
temp(I) := v1(v1'high - I + v1'low);
end loop ;
return temp;
end;
--***************************************************************************
function SUM( v2 : MVL7_VECTOR ) return integer is
variable v1: MVL7_VECTOR (v2'high downto v2'low);
variable count: integer:=0;
begin
v1 := v2;
for I in v1'high downto v1'low loop
if (v1(I) = '1') then
count := count + 1;
end if;
end loop ;
return count;
end;
--***************************************************************************
function PAD( v : MVL7_VECTOR ; width : integer ) return MVL7_VECTOR is
begin
return I2B(B2I(v),width);
end;
--***************************************************************************
function "*" ( x1 : MVL7_VECTOR ; x2 : MVL7_VECTOR ) return MVL7_VECTOR is
variable v1: MVL7_VECTOR (x1'high - x1'low downto 0);
variable v2: MVL7_VECTOR (x2'high - x2'low downto 0);
variable PROD: MVL7_VECTOR (v1'high downto v1'low);
begin
v1 := x1;
v2 := x2;
assert v1'length = v2'length
report "MVL7 vector MUL: operands of unequal lengths" severity FAILURE;
PROD := I2B(B2I(v1) * B2I(v2),PROD'length);
return (PROD);
end;
--***************************************************************************
function WiredOr (V: MVL7_VECTOR) return MVL7 is
variable result: MVL7;
begin
result := 'Z';
for i in V'range loop
result := tbl_WIREDOr(result, V(i));
exit when result = '1';
end loop;
return result;
end WiredOr;
--***************************************************************************
end;
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