Beispiel #1
0
/* set default state and make BDD for current state pair */
void gtaStoreDefault(unsigned p) 
{
  bdd_ptr united;
  int n;
  bdd_manager *tmpBddm;

  invariant(numExceptions == nextException);
  defState = p;

  tmpBddm = bdd_new_manager(100, 10); /* large enough to avoid rehashing??? */
  /* COULD AN ASSERTION CHECK THAT REHASHING DOES NOT OCCUR???????? */

  /* insert default state as leaf */
  def = bdd_find_leaf_hashed_add_root(tmpBddm, defState);

  /* insert paths for exceptions */
  for (exp = 0; exp < numExceptions; exp++) {
    for (n = 0; n < numOffs; n++)
      sortedPath[n] = exception[exp].path[sortedIndex[n]];

    bddPath[exp] = makePath(tmpBddm, exception[exp].value);
  }

  /* unite path roots */
  if (numExceptions == 0)
    united = def;
  else if (numExceptions == 1)
    united = bddPath[0];
  else
    united = unitePaths(tmpBddm);

  /* insert into result BDD manager */
  bdd_prepare_apply1(tmpBddm);
  bdd_apply1(tmpBddm, united, gta->ss[s].bddm, &fn_identity);
  bdd_kill_manager(tmpBddm);
  
  /* set behaviour entry */
  BEH(gta->ss[s], left, right) = BDD_LAST_HANDLE(gta->ss[s].bddm);
}
Beispiel #2
0
void makebdd(bdd_manager *bddm)
{
  bdd_manager *tmp_bddm;
  bdd_ptr united_bdds, default_ptr;
  int i;

  tmp_bddm = bdd_new_manager(8, 4);

  /*
  ** insert a leaf with value 'default_state' in tmp_bddm,
  ** if not already present
  */
  default_ptr = bdd_find_leaf_hashed(tmp_bddm, default_state, SEQUENTIAL_LIST(sub_results), &update_bddpaths); 

  for (exp_count = 0; exp_count < no_exceptions; exp_count++) {
    for (i = 0; i < offsets_size; i++)
      sorted_path[i] = exceptions[exp_count].path[sorted_indices[i]];

    /* clear the cache */
    bdd_kill_cache(tmp_bddm);
    bdd_make_cache(tmp_bddm, 8, 4);
    tmp_bddm->cache_erase_on_doubling = TRUE;

    bddpaths[exp_count] = makepath(tmp_bddm, 0, exceptions[exp_count].value, &update_bddpaths);
    PUSH_SEQUENTIAL_LIST(tmp_bddm->roots, unsigned, bddpaths[exp_count]);
  }    

  if (no_exceptions == 0)
    united_bdds = default_ptr;
  else if (no_exceptions == 1) 
    united_bdds = TOP_SEQUENTIAL_LIST(tmp_bddm->roots);
  else
    united_bdds = unite_roots(tmp_bddm);

  bdd_prepare_apply1(tmp_bddm);
  bdd_apply1(tmp_bddm, united_bdds, bddm, &fn_identity);       /* store the result in bddm->roots */

  bdd_kill_manager(tmp_bddm);
}
Beispiel #3
0
void double_table_and_cache_hashed(bdd_manager *bddm,
				   unsigned* some_roots,
				   void (*update_fn)(unsigned (*new_place)(unsigned node)),
				   unsigned *p_of_find, unsigned *q_of_find,
				   boolean rehash_p_and_q) {
  unsigned *p;  

  old_bddm = mem_alloc((size_t) sizeof (bdd_manager));
  *old_bddm = *bddm;

  /*make new bigger table, but only if a bigger one is possible */
  if (bddm->table_total_size > BDD_MAX_TOTAL_TABLE_SIZE) {
    printf("\nBDD too large (>%d nodes)\n", BDD_MAX_TOTAL_TABLE_SIZE);
    abort();
  }
  bddm->table_log_size++;
  bddm->table_size *= 2;
  bddm->table_overflow_increment *= 2;
  {
    unsigned desired_size = bddm->table_size + BDD_NUMBER_OF_BINS + 
      bddm->table_overflow_increment;
    bddm->table_total_size = (desired_size <= BDD_MAX_TOTAL_TABLE_SIZE)?
      desired_size: BDD_MAX_TOTAL_TABLE_SIZE;
  }
  bddm->node_table = (bdd_record*) 
    mem_alloc( (size_t)
	       bddm->table_total_size
	       * (sizeof (bdd_record)));
  bddm->table_mask =   bddm->table_size - BDD_NUMBER_OF_BINS; 
  
  bddm->table_double_trigger *= 2;
  bddm->table_overflow =  bddm->table_size + BDD_NUMBER_OF_BINS; 
#ifdef _BDD_STAT_
  bddm->number_double++;
#endif

  /* initialize to unused */
  bddm->table_elements = 0;
  mem_zero(&bddm->node_table[BDD_NUMBER_OF_BINS], (size_t)
	   bddm->table_size * (sizeof (bdd_record)));

  /* initialize bddm roots to the empty list, this new list will
     contain the rehashed addresses of old_bddm->roots*/
  MAKE_SEQUENTIAL_LIST(bddm->roots, unsigned, 1024);
  
  /*now rehash all nodes reachable from the old roots; we must be sure
    that the apply1 operation does not entail doubling of bddm node
    table: this is achieved by our having just doubled the size of the
    table*/

  

  bdd_prepare_apply1(old_bddm);

  for (p = SEQUENTIAL_LIST(old_bddm->roots); *p ;  p++) {
    bdd_apply1(old_bddm, *p, bddm, &double_leaf_fn);    
  }
 
  /*also make sure to rehash portion that is accessible from some_roots*/ 
  for (p = some_roots; *p;  p++) {
    if (*p != BDD_UNDEF)
	*p = bdd_apply1_dont_add_roots(old_bddm, *p, bddm, &double_leaf_fn);    
  }

  /*and fix values p_of_find and q_of_find if indicated*/
  if (rehash_p_and_q) {
    *p_of_find = 
	bdd_apply1_dont_add_roots(old_bddm, *p_of_find, bddm, &double_leaf_fn); 
    *q_of_find = 
	bdd_apply1_dont_add_roots(old_bddm, *q_of_find, bddm, &double_leaf_fn);
  }
  


  /*perform user supplied updates*/
  if (update_fn)
      (*update_fn)(&get_new_r);

  /*old_table now contains nodes whose mark field designates the
    new position of the node*/
  if (bddm->cache) {
    if (bddm->cache_erase_on_doubling) {
        bdd_kill_cache(bddm);
	bdd_make_cache(bddm, 2 * bddm->cache_size * CACHE_NUMBER_OF_BINS, 
		      2 * bddm->cache_overflow_increment * CACHE_NUMBER_OF_BINS);
      }
    else /*this is only a good idea when bddm is different from the  managers
	   the current apply operation is performed over*/
	double_cache(bddm, &get_new_r);
 }

  old_bddm->cache = (cache_record*) 0; /* old cache has been deallocated by now*/

  /*deallocated old table and old roots*/
  bdd_kill_manager(old_bddm);
}
Beispiel #4
0
int main() {
  bdd_manager *bddm, *bddm1;
  bdd_ptr zero, one;
  bdd_handle var2, var7;
  bdd_ptr and_2_7, nand_2_7;
  /*bdd_handle handle;*/

  bdd_init(); /* needed since we're using statistics */

  bddm = bdd_new_manager(100,50);
  /* get a BDD pointer to a node that is the leaf with value 0 */
  zero = bdd_find_leaf_hashed_add_root(bddm, 0);
  /* and a leaf with value 1 */
  one =  bdd_find_leaf_hashed_add_root(bddm, 1);
  /* note already at this point "zero" could have been invalidated if
     the table doubled, but we know that there is room for a 100
     nodes---anyway, this is really very bad style, so we go on in
     a more appropriate manner */

  /* "then" part is one, "else" part is zero */
  var2 = bdd_handle_find_node_hashed_add_root(bddm, zero, one, 2);
  var7 = bdd_handle_find_node_hashed_add_root(bddm, zero, one, 7);
  
  /* check node pointers and handles */
  assert(zero == BDD_ROOT(bddm, 0)); /* since table was not doubled */
  assert(one  == BDD_ROOT(bddm, 1)); 
  assert(var2 == 2);
  assert(var7 == 3);

  bddm1 = bdd_new_manager(100,50); /* make room for at least 100 nodes,
				      overflow increment is 50 */
  
  bdd_make_cache(bddm1, 100, 50); /* apply2 needs a result cache, here the size
				     is a hundred with increment 50 */

  /* apply operation on var2 and var7 in bddm; the result is 
     a completely fresh bdd in bddm1 and a BDD pointer, named "and_2_7" */
  and_2_7 = bdd_apply2_hashed(bddm, BDD_ROOT(bddm, var2), /* BDD #1 */
      			      bddm, BDD_ROOT(bddm, var7), /* BDD #2 */
			      bddm1, /* result BDD */
			      &and); /* leaf operation */
  
  bdd_update_statistics(bddm, 0); /* update statics group "0" with data from bddm 
				     before killing the manager */
 
  printf("Size of bddm: %d\n\n", bdd_size(bddm)); /* let's see the number of nodes created */
 
  bdd_kill_manager(bddm);
 
  printf("Size of bddm1: %d\n\n", bdd_size(bddm1));
 
  /*handle = BDD_LAST_HANDLE(bddm1);*/

  /*
  assert(handle == 0);
  assert(BDD_ROOT(bddm1, handle) == and_2_7);
  */

  /* reset all mark fields in bddm1 before an apply1 operation */
  bdd_prepare_apply1(bddm1); 
  
  /* a new bdd (which as an unlabelled graph is isomorphic to old one)
     in bddm1 is the result of the following apply operation */

  /* it's safe here to use and_2_7 since no operations were performed
     after it was calculated that could have entailed doubling of table */
  nand_2_7 = bdd_apply1(bddm1, and_2_7, bddm1, &not);
 
  bdd_update_statistics(bddm1, 1);
  printf("Size of bddm1: %d\n\n", bdd_size(bddm1));

  print_bdd(bddm1, and_2_7);
  printf("\n\n");
  print_bdd(bddm1, nand_2_7);
  printf("\n\n");

  bdd_kill_manager(bddm1);

  bdd_print_statistics(0, "bddm"); /* print group 0 statistics with heading "bddm" */
  bdd_print_statistics(1, "bddm1"); /* print group 1 statistics with heading "bddm1" */
  return 0;
}