subtype instruction_word_t is std_logic_vector(WORD_WIDTH-1 downto 0);
subtype instruction_addr_t is std_logic_vector(INSTR_ADDR_WIDTH-1 downto 0);
+ subtype instr_addr_t is instruction_addr_t;
subtype gp_addr_t is std_logic_vector(REG_ADDR_WIDTH-1 downto 0);
subtype data_ram_word_t is std_logic_vector(WORD_WIDTH-1 downto 0);