extern int sys_read(int,int);
extern int sys_request(int,int);
extern int sys_write(int,int);
extern int vocab_get(int);
extern int vocab_set(int,int);
extern void push(int);
extern int pop(void);
extern void rpush(int);
extern int rpop(void);
extern void rinit(void);
static char memseg[1024] =
  { 0, 0, 0, 9, 'i', 'n', 't', 'e', 'r', 'p', 'r', 'e', 't', 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 2, 0, 0, 0, 16, 0, 0, 0, 13, 0, 0, 0, 1
  };
static int interpret(int,int);
int main(void) {
  /* int start, here, eax, ebx, esi, mode;
  here = (int) memseg + 512;
  mode = here;
  *(int*) mode = 11; //executing
  here += 4;
  //string "interpret"
  eax = here;
  *(int*)here++ = 9;
  *(char*)here++ = 'i';
  *(char*)here++ = 'n';
  *(char*)here++ = 't';
  *(char*)here++ = 'e';
  *(char*)here++ = 'r';
  *(char*)here++ = 'p';
  *(char*)here++ = 'r';
  *(char*)here++ = 'e';
  *(char*)here++ = 't';
  here += 3; //align
  //initial definition of "interpret"
  esi = here;
  *(int*)here++ = 4;  //WORD
  *(int*)here++ = 2;  //LIT
  *(int*)here++ = mode; //addr of mode var
  *(int*)here++ = 10; //FETCH
  *(int*)here++ = 12; //EXECUTE
  *(int*)here++ = 13; //NOOP
  *(int*)here++ = 1;  //RET
  //insert into vocab
  vocab_set(eax, esi);
  //string "quit"
  ebx = esi;
  eax = here;
  *(int*)here++ = 4;
  *(char*)here++ = 'q';
  *(char*)here++ = 'u';
  *(char*)here++ = 'i';
  *(char*)here++ = 't';
  //initial definition of "quit"
  esi = here;
  *(int*)here++ = 3; //rinit
  *(int*)here++ = ebx; //interpret
  *(int*)here++ = 9; //JMP
  *(int*)here++ = esi; //jmp addr 0 (interpret)
  //insert into vocab
  vocab_set(eax, esi); */
  return interpret((int)memseg, (int)memseg);
}
static int interpret(int esi, int here) {
  int eax = 0, ebx = 0, ecx = 0, edi = 0;
 next:
  eax = *(int*) esi;
  esi += 4;
 exec:
  switch(eax) {
  case 0: //interpret
    esi = eax;
    eax = *(int*)eax;
    goto next;
  case 1: // ret (exit)
    esi = rpop();
    goto next;
  case 2: // pushnext (lit)
    push(*(int*)esi);
    esi += 4;
    goto next;
  case 3: // rinit
    rinit();
    goto next;
  case 4: // word
    esi += eax;
    eax += esi;
    goto next;
  case 5: // sys_read
    sys_read(pop(),pop());
    goto next;
  case 6: // sys_request
    sys_request(pop(),pop());
    goto next;
  case 7: // sys_write
    sys_write(pop(),pop());
    goto next;
  case 8: // bye
    break;
  case 9: // goto
    esi = *(int*) esi;
    goto next;
  case 10: // @ fetch
    push(*(int*)pop());
    goto next;
  case 11: // ! set
    *(int*)pop() = pop();
    goto next;
  case 12: // EXECUTE
    eax = pop();
    goto exec;
  case 13: // NOOP
    push(1);
    goto next;
  default: // eax is an addr, jump to it and push esi
    rpush(esi);
    esi = eax;
    goto next;
  }
  return 0;
}