Hash *luaH_new(int32 nhash) {
Hash *t = luaM_new(Hash);
nhash = luaO_redimension((int32)((float)nhash / REHASH_LIMIT));
nodevector(t) = hashnodecreate(nhash);
nhash(t) = nhash;
nuse(t) = 0;
t->htag = TagDefault;
luaO_insertlist(&roottable, (GCnode *)t);
nblocks += gcsize(nhash);
return t;
}
static int newsize (stringtable *tb)
{
int size = tb->size;
int realuse = 0;
int i;
/* count how many entries are really in use */
for (i=0; i<size; i++)
if (tb->hash[i] != NULL && tb->hash[i] != &EMPTY)
realuse++;
if (2*(realuse+1) <= size) /* +1 is the new element */
return size; /* don't need to grow, just rehash to clear EMPTYs */
else
return luaO_redimension(size);
}
static void rehash(Hash *t) {
int32 nold = nhash(t);
Node *vold = nodevector(t);
int32 i;
if (!emptyslots(t))
nhash(t) = luaO_redimension(nhash(t));
nodevector(t) = hashnodecreate(nhash(t));
for (i = 0; i < nold; i++) {
Node *n = vold + i;
if (ttype(ref(n)) != LUA_T_NIL && ttype(val(n)) != LUA_T_NIL)
*node(t, present(t, ref(n))) = *n; // copy old node to luaM_new hash
}
nblocks += gcsize(t->nhash) - gcsize(nold);
luaM_free(vold);
}
static int newsize (Hash *t)
{
Node *v = t->node;
int size = nhash(t);
int realuse = 0;
int i;
for (i=0; i<size; i++) {
if (ttype(ref(v+i)) != LUA_T_NIL && ttype(val(v+i)) != LUA_T_NIL)
realuse++;
}
if (2*(realuse+1) <= size) /* +1 is the new element */
return size; /* don't need to grow, just rehash */
else
return luaO_redimension(size);
}
