- wire `fetch_action fetch_action;
- wire [31:0] fetch_target_pc;
- wire [31:0] fetch_output_pc;
- wire [31:0] fetch_output_instruction;
- wire `fetch_output_state fetch_output_state;
-
- cpu_fetch_stage #(
- .reset_vector(reset_vector),
- .mtvec(mtvec)
- ) fetch_stage(
- .clk(clk),
- .reset(reset),
- .memory_interface_fetch_address(memory_interface_fetch_address),
- .memory_interface_fetch_data(memory_interface_fetch_data),
- .memory_interface_fetch_valid(memory_interface_fetch_valid),
- .fetch_action(fetch_action),
- .target_pc(fetch_target_pc),
- .output_pc(fetch_output_pc),
- .output_instruction(fetch_output_instruction),
- .output_state(fetch_output_state)
- );
-
- wire [6:0] decoder_funct7;
- wire [2:0] decoder_funct3;
- wire [4:0] decoder_rd;
- wire [4:0] decoder_rs1;
- wire [4:0] decoder_rs2;
- wire [31:0] decoder_immediate;
- wire [6:0] decoder_opcode;
- wire `decode_action decode_action;
-
- cpu_decoder decoder(
- .instruction(fetch_output_instruction),
- .funct7(decoder_funct7),
- .funct3(decoder_funct3),
- .rd(decoder_rd),
- .rs1(decoder_rs1),
- .rs2(decoder_rs2),
- .immediate(decoder_immediate),
- .opcode(decoder_opcode),
- .decode_action(decode_action));
-
- wire [31:0] register_rs1 = (decoder_rs1 == 0) ? 0 : registers[decoder_rs1];
- wire [31:0] register_rs2 = (decoder_rs2 == 0) ? 0 : registers[decoder_rs2];
-
- wire [31:0] load_store_address = decoder_immediate + register_rs1;
-
- wire [1:0] load_store_address_low_2 = decoder_immediate[1:0] + register_rs1[1:0];
-
- function get_load_store_misaligned(
- input [2:0] funct3,
- input [1:0] load_store_address_low_2
- );
- begin
- case(funct3[1:0])
- `funct3_sb:
- get_load_store_misaligned = 0;
- `funct3_sh:
- get_load_store_misaligned = load_store_address_low_2[0] != 0;
- `funct3_sw:
- get_load_store_misaligned = load_store_address_low_2[1:0] != 0;
- default:
- get_load_store_misaligned = 1'bX;
- endcase
- end
- endfunction
-
- wire load_store_misaligned = get_load_store_misaligned(decoder_funct3, load_store_address_low_2);
-
- assign memory_interface_rw_address = load_store_address[31:2];
-
- wire [3:0] unshifted_load_store_byte_mask = {decoder_funct3[1] ? 2'b11 : 2'b00, (decoder_funct3[1] | decoder_funct3[0]) ? 1'b1 : 1'b0, 1'b1};