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library ieee;
use ieee.std_logic_1164.all;
library ieee;
use ieee.numeric_std.all;
entity shl_211 is
port (
output : out std_logic_vector(31 downto 0);
input : in std_logic_vector(31 downto 0);
shift : in std_logic_vector(5 downto 0);
padding : in std_logic
);
end shl_211;
architecture augh of shl_211 is
signal tmp_padding : std_logic;
signal tmp_result : std_logic_vector(32 downto 0);
-- Little utility functions to make VHDL syntactically correct
-- with the syntax to_integer(unsigned(vector)) when 'vector' is a std_logic.
-- This happens when accessing arrays with <= 2 cells, for example.
function to_integer(B: std_logic) return integer is
variable V: std_logic_vector(0 to 0);
begin
V(0) := B;
return to_integer(unsigned(V));
end;
function to_integer(V: std_logic_vector) return integer is
begin
return to_integer(unsigned(V));
end;
begin
-- Temporary signals
tmp_padding <= padding;
tmp_result <= std_logic_vector(shift_left( unsigned(input & padding), to_integer(shift) ));
-- The output
output <= tmp_result(32 downto 1);
end architecture;
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