void intro_sort ( iter_t first, iter_t last,compare comp = compare())
{ //------------------------- begin ----------------------
auto N = last - first;
assert ( N > 0);
uint32_t Level = (MS1B ( N)+1)<<1 ;
intro_sort_internal ( first , last, Level,comp);
};
void hopscotch_fill(struct hopscotch_t* h, iter_t iter, void* opaque)
{
for (int i = 0; i < h->size; i++) h->array[i] = *(iter(opaque));
struct stats_t stats;
create_stats(&h->array[0], h->size, &stats);
int target_value = h->size / 20;
h->neighborhood_size = (CACHE_LINE_BYTES / 2) / sizeof(item_t);
int needed_bits = MS1B(h->size);
if (h->size > ((1 << needed_bits) + h->neighborhood_size - 1)) needed_bits++;
for (;;)
{
h->mask = choose_hash_func_mask(&stats, needed_bits, target_value);
h->bits_used = popcount(h->mask);
int num_buckets = 1 << h->bits_used;
//printf("size: %d, num_buckets: %d\n", h->size, num_buckets);
h->buckets = (item_t*)calloc(num_buckets + h->neighborhood_size - 1, sizeof(item_t));
int *metadata = (int*)calloc(num_buckets + h->neighborhood_size - 1, sizeof(int));
for (int item_being_placed = 0; item_being_placed < h->size; item_being_placed++)
{
//printf("begin trying to place item #%d: %08X\n", item_being_placed, h->array[item_being_placed]);
int key = (int)apply_simple_hash_function(h->array[item_being_placed], h->mask);
//printf("key is: %d\n", key);
int probe = key;
int neighborhood_i = 0;
for ( ; neighborhood_i < h->neighborhood_size; probe++, neighborhood_i++)
{
if (h->buckets[probe] == 0)
{
place_in_keys_neighborhood:
//printf("placing into bucket %d, as item %d of key %d\n", probe, neighborhood_i, key);
h->buckets[probe] = h->array[item_being_placed];
metadata[key] |= 1 << neighborhood_i;
goto has_placed;
}
}
//printf("searching for empty bucket away from neighborhood\n");
for ( ; probe < num_buckets + h->neighborhood_size; probe++)
if (h->buckets[probe] == 0)
goto has_found_empty_bucket;
goto failed_to_find_space;
has_found_empty_bucket:
//printf("found empty bucket in #%d\n", probe);
do
{
for (int probe_back = 1; probe_back < h->neighborhood_size; probe_back++)
{
if (!metadata[probe - probe_back]) continue;
for (int thing_to_relocate = 0; thing_to_relocate < probe_back; thing_to_relocate++)
{
if (metadata[probe - probe_back] & (1 << thing_to_relocate))
{
//printf("moving item %08X that was in bucket #%d (as item %d of key #%d) into bucket #%d (as item %d of key #%d)\n",
//h->buckets[probe - probe_back + thing_to_relocate],
//probe - probe_back + thing_to_relocate, thing_to_relocate, probe - probe_back,
//probe, probe_back, probe - probe_back);
h->buckets[probe] = h->buckets[probe - probe_back + thing_to_relocate];
metadata[probe - probe_back] &= ~(1 << thing_to_relocate);
metadata[probe - probe_back] |= (1 << probe_back);
probe = probe - probe_back + thing_to_relocate;
goto next_hop;
}
}
}
goto failed_to_find_space;
next_hop:
;
}
while (probe - key >= h->neighborhood_size);
neighborhood_i = probe - key;
goto place_in_keys_neighborhood;
has_placed:
;
}
free(metadata);
destroy_stats(&stats);
return;
failed_to_find_space:
free(metadata);
free(h->buckets);
needed_bits++;
}
}
