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diff --git a/testsuite/gna/issue50/idct.d/sub_160.vhd b/testsuite/gna/issue50/idct.d/sub_160.vhd
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+library ieee;
+use ieee.std_logic_1164.all;
+
+library ieee;
+use ieee.numeric_std.all;
+
+entity sub_160 is
+ port (
+ le : out std_logic;
+ result : out std_logic_vector(31 downto 0);
+ in_a : in std_logic_vector(31 downto 0);
+ in_b : in std_logic_vector(31 downto 0);
+ sign : in std_logic
+ );
+end sub_160;
+
+architecture augh of sub_160 is
+
+ signal carry_inA : std_logic_vector(33 downto 0);
+ signal carry_inB : std_logic_vector(33 downto 0);
+ signal carry_res : std_logic_vector(33 downto 0);
+
+ -- Signals to generate the comparison outputs
+ signal msb_abr : std_logic_vector(2 downto 0);
+ signal tmp_sign : std_logic;
+ signal tmp_eq : std_logic;
+ signal tmp_le : std_logic;
+ signal tmp_ge : std_logic;
+
+begin
+
+ -- To handle the CI input, the operation is '0' - CI
+ -- If CI is not present, the operation is '0' - '0'
+ carry_inA <= '0' & in_a & '0';
+ carry_inB <= '0' & in_b & '0';
+ -- Compute the result
+ carry_res <= std_logic_vector(unsigned(carry_inA) - unsigned(carry_inB));
+
+ -- Set the outputs
+ result <= carry_res(32 downto 1);
+
+ -- Other comparison outputs
+
+ -- Temporary signals
+ msb_abr <= carry_inA(32) & carry_inB(32) & carry_res(32);
+ tmp_sign <= sign;
+ tmp_eq <= '1' when in_a = in_b else '0';
+
+ tmp_le <=
+ tmp_eq when msb_abr = "000" or msb_abr = "110" else
+ '1' when msb_abr = "001" or msb_abr = "111" else
+ '1' when tmp_sign = '0' and (msb_abr = "010" or msb_abr = "011") else
+ '1' when tmp_sign = '1' and (msb_abr = "100" or msb_abr = "101") else
+ '0';
+
+ tmp_ge <=
+ '1' when msb_abr = "000" or msb_abr = "110" else
+ '1' when tmp_sign = '0' and (msb_abr = "100" or msb_abr = "101") else
+ '1' when tmp_sign = '1' and (msb_abr = "010" or msb_abr = "011") else
+ '0';
+
+ le <= tmp_le;
+
+end architecture;