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library ieee;
use ieee.std_logic_1164.all;
use ieee.numeric_std.all;
entity repro is
port (val : std_logic_vector (63 downto 0);
iperm : std_logic_vector (3*8 - 1 downto 0);
en : std_ulogic;
res : out std_logic_vector (63 downto 0));
end entity repro;
architecture behaviour of repro is
type arecordtype is record
valid : std_ulogic;
write_data : std_ulogic_vector(63 downto 0);
end record;
signal a : arecordtype;
subtype byte_index_t is unsigned(2 downto 0);
type permutation_t is array(0 to 7) of byte_index_t;
signal perm : permutation_t := (others => "000");
begin
writeback_1: process(all)
variable j : integer;
begin
for i in 0 to 7 loop
j := to_integer(perm(i)) * 8;
res(i * 8 + 7 downto i * 8) <= a.write_data(j + 7 downto j);
end loop;
end process;
a.valid <= en;
a.write_data <= val;
process (iperm) is
begin
for i in 0 to 7 loop
perm (i) <= unsigned (iperm (i*3 + 2 downto i*3));
end loop;
end process;
end;
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