main.c

#include "apex_cpu.h"

// forward declarations
void generate_prompt(APEX_CPU *cpu, const char *filename);
void clear_buffer();

int main(int argc, char const *argv[]) {
  APEX_CPU *cpu = NULL;

  if (argc < 2) {
    fprintf(stderr, "APEX_Help: Usage %s <input_file>\n", argv[0]);
    exit(1);
  }

  printf("\n-----------------------------------------------------------------------------------------------");
  printf("\n                                  APEX Simulator v2.0\n");
  printf("-----------------------------------------------------------------------------------------------");
  printf("\n  commands: [init | initialize] [s|Simulate <count>] [d|Display] [showmem <address>] [n] \n");
  printf("-----------------------------------------------------------------------------------------------\n");

  generate_prompt(cpu, argv[1]);

  if (cpu != NULL) APEX_cpu_stop(cpu);
  return 0;
}

/**
 * Method to return user prompt, parse user input and call appropriate methods in apex_cpu.c & apex_cpu_b.c
 *
 * @param cpu pointer to the current instance of cpu
 * @param filename name of the input file
 */
void generate_prompt(APEX_CPU *cpu, const char *filename) {
  char user_prompt_val[50];
  int count, address;

  while (TRUE) {
    printf("\nAPEX:> ");
    scanf("%s", user_prompt_val);

    if (strcmp(user_prompt_val, "Q") == 0 || strcmp(user_prompt_val, "q") == 0) {
      printf("APEX_CPU: Simulation Stopped\n");
      if (cpu != NULL) APEX_cpu_stop(cpu);
      break;
    } else if (strcmp(user_prompt_val, "initialize") == 0 || strcmp(user_prompt_val, "init") == 0) {
      cpu = APEX_cpu_init(filename);
      if (!cpu) {
        fprintf(stderr, "APEX_Error: Unable to initialize CPU\n");
        exit(1);
      }
    } else if (strcmp(user_prompt_val, "n") == 0 || strcmp(user_prompt_val, "next") == 0) {
      APEX_cpu_run(cpu, 0, true);
    } else {

      if (strcmp(user_prompt_val, "display") == 0 || strcmp(user_prompt_val, "Display") == 0) {
        display(cpu);
        clear_buffer();

      } else if (strcmp(user_prompt_val, "print_rob") == 0 || strcmp(user_prompt_val, "PrintROB") == 0) {
        print_reorder_buffer(cpu);
        clear_buffer();

      } else if (strcmp(user_prompt_val, "print_iq") == 0 || strcmp(user_prompt_val, "PrintIQ") == 0) {
        print_issue_queue(cpu);
        clear_buffer();

      } else if (strcmp(user_prompt_val, "simulate") == 0 || strcmp(user_prompt_val, "Simulate") == 0) {
        scanf("%d", &count);
        APEX_cpu_run(cpu, count, true);
        clear_buffer();

      } else if (strcmp(user_prompt_val, "showmem") == 0 || strcmp(user_prompt_val, "ShowMem") == 0) {
        scanf("%d", &address);
        show_mem(cpu, address);
        clear_buffer();

      } else {
        clear_buffer();
        printf(
            "Invalid Command: [ %s ] \n\n--------------------------------------------------------------------",
            user_prompt_val);
        printf("\n commands supported:\n");
        printf("--------------------------------------------------------------------\n");
        printf("   [initialize | init]     - to initialize cpu\n"
               "   [s|Simulate <count>]    - to simulate <count> cycles\n"
               "   [d|Display]             - to display stage contents\n"
               "   [showmem <address>]     - to show contents in memory <address>\n"
               "   [PrintROB | print_rob]  - to print contents of ROB\n"
               "   [PrintIQ | print_iq]    - to print contents of Issue Queue\n"
               "   [n|next]                - proceed by one cycle\n");
        printf("--------------------------------------------------------------------\n");
      }
    }
    if (cpu != NULL) {
      if ((cpu->insn_completed == cpu->code_memory_size) &&
          ((strcmp(user_prompt_val, "simulate") == 0 || strcmp(user_prompt_val, "Simulate") == 0) ||
              strcmp(user_prompt_val, "n") == 0 || strcmp(user_prompt_val, "N") == 0)) {
        printf("\nAPEX_CPU: Simulation Complete, cycles = %d instructions retired = %d\n",
               cpu->clock, cpu->insn_completed);
      }
    }
  }
}

/**
 * Method to remove extraneous characters after necessary user input has been read by scanf()
 */
void clear_buffer() {
  while (getchar() != '\n') {}
}