You are an expert Verilog hardware designer working on a complete FPGA or ASIC project. You are given the full source code of a Verilog project. One of the modules in the project is incomplete — its implementation is missing and marked with:

// >>> Module Implementation Begin

// <<< Module Implementation End

Your task is to complete the missing implementation so that the entire project functions correctly. You must infer what the missing module or logic is supposed to do by analyzing the rest of the codebase: module names, signal connections, instantiations, comments, and usage patterns.

Follow these rules:

1. Only generate Verilog code to go between the `// >>> Module Implementation Begin` and `// <<< Module Implementation End` comments.
2. Use Verilog-2001 syntax. Ensure the code is synthesizable.
3. Assume the goal is a working, integrated hardware design — your code must make the whole system function as intended.
4. Analyze the naming, I/O ports, and how the module is instantiated or used in other parts of the project.
5. Implement correct behavior based on design context. Do not guess randomly — reason it out.
6. Avoid vendor-specific features unless explicitly required.
7. Do not output comments, explanation, or anything outside the required code region unless explicitly asked.

Your output should contain **only the Verilog code** that fits inside the marked region.

`timescale 1ns / 1ps
// Code your design here

//program counter-------------------------------------------

module program_counter(
  input clk,
  input rst,
  input [3:0] pc_addr_in,
  output reg [3:0] pc_addr_out
);
  
  always @ (posedge clk or posedge rst)
    begin
      if(rst)
        pc_addr_out <= 4'b0;
      else
        pc_addr_out <= pc_addr_in;
    end
  
endmodule

//instruction memory-----------------------------------------

module instruction_memory(
  input [3:0] addr_in,
  output reg [7:0] instruction
);
  
  reg [7:0] memory [0:15];
  
  initial
    begin
      memory[0] = 8'hAB;
      memory[1] = 8'hDE;
      memory[2] = 8'h3C;
      memory[3] = 8'hD6;
      memory[4] = 8'hBC;
      memory[5] = 8'hCD;
      memory[6] = 8'hAE;
      memory[7] = 8'hA1;
      memory[8] = 8'hB2;
      memory[9] = 8'hD4;
      memory[10] = 8'hE5;
      memory[11] = 8'hF6;
      memory[12] = 8'hAF;
      memory[13] = 8'hEF;
      memory[14] = 8'h67;
      memory[15] = 8'h88;
    end
  
  always @ (*) instruction = memory[addr_in];
  
endmodule

//Control unit----------------------------------------------

module control_unit(
  input [1:0] opcode,
  output reg reg_write,
  output reg pc_src,
  output reg [2:0] alu_op
);
// >>> Module Implementation Begin

// <<< Module Implementation End
endmodule



//resister file----------------------------------------------------

module register_file(
  input clk,
  input reg_write,
  input [1:0] source_reg1,
  input [1:0] source_reg2,
  input [1:0] destinition_reg,
  input [7:0] write_data,
  output  [7:0] data_out_source_reg1,
  output  [7:0] data_out_source_reg2
);
  
  reg [7:0] memory [0:3];
  
  initial
    begin
      memory[0] = 8'haa;
      memory[1] = 8'h1a;
      memory[2] = 8'h33;
      memory[3] = 8'hdd;

    end
  
     assign data_out_source_reg1 = memory[source_reg1];
     assign data_out_source_reg2 = memory[source_reg2];

  always @ (posedge clk)
    begin
      if(reg_write)
        memory[destinition_reg] <= write_data;
    end
  
endmodule

// 8 bit ALU-----------------------------------------------------

module arithmatic_logical_unit(
  input [7:0] alu_in1,
  input [7:0] alu_in2,
  input [2:0] alu_op,
  output reg [7:0] alu_out
);
  
  always @ (*)
    begin
      case(alu_op)
        3'b001 : alu_out = alu_in1 + alu_in2; // addition
        3'b010 : alu_out = alu_in1 & alu_in2; // bitwise and
        3'b011 : alu_out = alu_in1 | alu_in2; // bitwise and
        default: alu_out = 8'b0;
      endcase
    end
  
endmodule


//processor module-----------------------------------------------------

module processor(
  input clk,
  input rst,
  output [3:0] addr_out,
  output [7:0] instruction,
  output [1:0] opcode,
  output       reg_write,
  output       pc_src,
  output [2:0] alu_op,
  output [7:0] data_out_source_reg1,
  output [7:0] data_out_source_reg2,
  output [7:0] alu_out
);
  
  wire [3:0] addr_in;
  wire [1:0] source_reg1,source_reg2,destinition_reg;
  
  program_counter pc (clk,rst,addr_in,addr_out); // program counter
  instruction_memory im (addr_out,instruction);
  assign opcode = instruction[7:6];
  assign source_reg1 = instruction[5:4];
  assign source_reg2 = instruction[3:2];
  assign destinition_reg = instruction[1:0];
  
  control_unit cu (opcode,reg_write,pc_src,alu_op); // control_unit
  register_file rf (clk, reg_write,source_reg1,source_reg2,destinition_reg,alu_out,data_out_source_reg1,data_out_source_reg2); // resister file
  
  arithmatic_logical_unit alu (data_out_source_reg1,data_out_source_reg2,alu_op,alu_out); // 8 bit alu
  
 assign addr_in = (pc_src) ? 4'b000 : addr_out + 1;
endmodule

//top module---------------------------------------------------------------------------------------------------

module tt_um_myprocessor (
    input  wire clk,              // Clock from Tiny Tapeout
    input  wire rst_n, 
    input wire ena,// Active-low reset
    input  wire [7:0] ui_in,  
    input  wire [7:0] uio_in,   // IOs: Input path
    output wire [7:0] uio_out,
    output wire [7:0] uo_out, 
    output wire [7:0] uio_oe // 8-bit output
    );

    // Internal connections to your processor
    wire [3:0] addr_out;
    wire [7:0] instruction;
    wire [1:0] opcode;
    wire       reg_write;
    wire       pc_src;
    wire [2:0] alu_op;
    wire [7:0] data_out_source_reg1;
    wire [7:0] data_out_source_reg2;
    wire [7:0] alu_out;

    // Instantiate your processor
    processor cpu (clk,rst_n,addr_out,instruction,opcode,reg_write,pc_src,alu_op,data_out_source_reg1,data_out_source_reg2,alu_out);

    // Choose what to output (here we show ALU result)
    assign uo_out = alu_out;
    assign uio_out  = 8'b00000000; // Not used
    assign uio_oe   = 8'b00000000; // All inputs
  // wire _unused = &{uio_oe,uio_ot,uio_in,ui_in,1'b0};

endmodule


Reference solution:
rtl/generated.v:   
  
  always @ (*)
    begin
      reg_write =0;
      pc_src = 0;
      alu_op = 3'b000;
      case(opcode)
        2'b00 : begin
                  reg_write = 1;   // write in register file
                  alu_op = 3'b001; // Addition op
                end
        2'b01 : begin
                  reg_write = 1; // write in register file
          		  alu_op = 3'b010;// AND op
        		end
        2'b10 : begin
                  reg_write = 1;// write in register file
          		  alu_op = 3'b011; // OR op
        		end
        2'b11 : begin
                  pc_src = 1;// Jump op        		 
        		end
      endcase
    end