static int traverseephemeron (global_State *g, Table *h, int inv) {
  int marked = 0;  /* true if an object is marked in this traversal */
  int hasclears = 0;  /* true if table has white keys */
  int hasww = 0;  /* true if table has entry "white-key -> white-value" */
  unsigned int i;
  unsigned int asize = luaH_realasize(h);
  unsigned int nsize = sizenode(h);
  /* traverse array part */
  for (i = 0; i < asize; i++) {
    if (valiswhite(&h->array[i])) {
      marked = 1;
      reallymarkobject(g, gcvalue(&h->array[i]));
    }
  }
  /* traverse hash part; if 'inv', traverse descending
     (see 'convergeephemerons') */
  for (i = 0; i < nsize; i++) {
    Node *n = inv ? gnode(h, nsize - 1 - i) : gnode(h, i);
    if (isempty(gval(n)))  /* entry is empty? */
      clearkey(n);  /* clear its key */
    else if (iscleared(g, gckeyN(n))) {  /* key is not marked (yet)? */
      hasclears = 1;  /* table must be cleared */
      if (valiswhite(gval(n)))  /* value not marked yet? */
        hasww = 1;  /* white-white entry */
    }
    else if (valiswhite(gval(n))) {  /* value not marked yet? */
      marked = 1;
      reallymarkobject(g, gcvalue(gval(n)));  /* mark it now */
    }
  }
  /* link table into proper list */
  if (g->gcstate == GCSpropagate)
    linkgclist(h, g->grayagain);  /* must retraverse it in atomic phase */
  else if (hasww)  /* table has white->white entries? */
    linkgclist(h, g->ephemeron);  /* have to propagate again */
  else if (hasclears)  /* table has white keys? */
    linkgclist(h, g->allweak);  /* may have to clean white keys */
  else if (g->gckind == KGC_GEN)
    linkgclist(h, g->grayagain);  /* keep it in some list */
  else
    gray2black(h);
  return marked;
}
Unknown