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void execute_instructions(System *sys)
{
  while (1) // set to true for now
  {
    int current_eip = sys->registers[EIP]; // get current eip

    // valid eip
    if (current_eip < 0 || current_eip % 4 != 0)
    {
      break;
    }

    int instruction_loc = current_eip / 4;               // location of instruction
    if (instruction_loc >= sys->memory.num_instructions) // break loop in this case
    {
      break;
    }

    char *instruction_string = sys->memory.instruction[instruction_loc]; // instruction string

    // if its end, break the loop
    if (strcmp(instruction_string, "END") == 0)
    {
      break;
    }

    // code to skip over the labels
    if (instruction_string[0] == '.')
    {
      sys->registers[EIP] += 4;
      continue; // go to next iteration
    }

    char inst_copy[256];
    strcpy(inst_copy, instruction_string); // copy over

    // string operations to get operator, src, and dst
    char *operation = strtok(inst_copy, " ,\t");
    char *src = strtok(NULL, " ,\t");
    char *dst = strtok(NULL, " ,\t");

    // set the reult to success for now
    ExecResult result = SUCCESS;

    // check operartion
    if (strcmp(operation, "MOVL") == 0) // movl
    {
      if (!src || !dst)
      {
        result = INSTRUCTION_ERROR;
      }
      else
      {
        result = execute_movl(sys, src, dst);
      }
    }
    else if (strcmp(operation, "ADDL") == 0) // addl
    {
      if (!src || !dst)
      {
        result = INSTRUCTION_ERROR;
      }
      else
      {
        result = execute_addl(sys, src, dst);
      }
    }
    else if (strcmp(operation, "PUSHL") == 0) // pushl
    {
      if (!src)
      {
        result = INSTRUCTION_ERROR;
      }
      else
      {
        result = execute_push(sys, src);
      }
    }
    else if (strcmp(operation, "POPL") == 0) // popl
    {
      if (!src)
      {
        result = INSTRUCTION_ERROR;
      }
      else
      {
        result = execute_pop(sys, src);
      }
    }
    else if (strcmp(operation, "CMPL") == 0) // comparison
    {
      if (!src || !dst)
      {
        result = INSTRUCTION_ERROR;
      }
      else
      {
        result = execute_cmpl(sys, src, dst);
      }
    }
    else if (strcmp(operation, "CALL") == 0) // call
    {
      if (!src)
      {
        result = INSTRUCTION_ERROR;
      }
      else
      {
        result = execute_call(sys, src);
      }
    }
    else if (strcmp(operation, "RET") == 0) // returning
    {
      result = execute_ret(sys);
    }
    else if (strcmp(operation, "JMP") == 0 || strcmp(operation, "JE") == 0 ||
             strcmp(operation, "JNE") == 0 || strcmp(operation, "JL") == 0 ||
             strcmp(operation, "JG") == 0) // handle the jump operators
    {
      if (!src)
      {
        result = INSTRUCTION_ERROR;
      }
      else
      {
        result = execute_jmp(sys, operation, src);
      }
    }
    else
    {
      // instruction doesn't work
      sys->registers[EIP] += 4;
      continue;
    }
    // check for execution issues
    if (result != SUCCESS)
    {
      break;
    }
    else
    {
      // increment program counter
      if (strcmp(operation, "MOVL") == 0 || strcmp(operation, "ADDL") == 0 ||
          strcmp(operation, "PUSHL") == 0 || strcmp(operation, "POPL") == 0 ||
          strcmp(operation, "CMPL") == 0)
      {
        sys->registers[EIP] += 4;
      }
    }
  }
}