/**
* mono_conc_hashtable_insert
*
* @Returns the old value if key is already present or null
*/
gpointer
mono_conc_hashtable_insert (MonoConcurrentHashTable *hash_table, gpointer key, gpointer value)
{
conc_table *table;
key_value_pair *kvs;
int hash, i, table_mask;
g_assert (key != NULL && key != TOMBSTONE);
g_assert (value != NULL);
hash = mix_hash (hash_table->hash_func (key));
mono_mutex_lock (hash_table->mutex);
if (hash_table->element_count >= hash_table->overflow_count)
expand_table (hash_table);
table = (conc_table*)hash_table->table;
kvs = table->kvs;
table_mask = table->table_size - 1;
i = hash & table_mask;
if (!hash_table->equal_func) {
for (;;) {
if (!kvs [i].key || kvs [i].key == TOMBSTONE) {
kvs [i].value = value;
/* The write to values must happen after the write to keys */
mono_memory_barrier ();
kvs [i].key = key;
++hash_table->element_count;
mono_mutex_unlock (hash_table->mutex);
return NULL;
}
if (key == kvs [i].key) {
gpointer value = kvs [i].value;
mono_mutex_unlock (hash_table->mutex);
return value;
}
i = (i + 1) & table_mask;
}
} else {
GEqualFunc equal = hash_table->equal_func;
for (;;) {
if (!kvs [i].key || kvs [i].key == TOMBSTONE) {
kvs [i].value = value;
/* The write to values must happen after the write to keys */
mono_memory_barrier ();
kvs [i].key = key;
++hash_table->element_count;
mono_mutex_unlock (hash_table->mutex);
return NULL;
}
if (equal (key, kvs [i].key)) {
gpointer value = kvs [i].value;
mono_mutex_unlock (hash_table->mutex);
return value;
}
i = (i + 1) & table_mask;
}
}
}
gpointer
mono_conc_hashtable_lookup (MonoConcurrentHashTable *hash_table, gpointer key)
{
MonoThreadHazardPointers* hp;
conc_table *table;
int hash, i, table_mask;
key_value_pair *kvs;
hash = mix_hash (hash_table->hash_func (key));
hp = mono_hazard_pointer_get ();
retry:
table = (conc_table *)get_hazardous_pointer ((gpointer volatile*)&hash_table->table, hp, 0);
table_mask = table->table_size - 1;
kvs = table->kvs;
i = hash & table_mask;
if (G_LIKELY (!hash_table->equal_func)) {
while (kvs [i].key) {
if (key == kvs [i].key) {
gpointer value;
/* The read of keys must happen before the read of values */
mono_memory_barrier ();
value = kvs [i].value;
/* FIXME check for NULL if we add suppport for removal */
mono_hazard_pointer_clear (hp, 0);
return value;
}
i = (i + 1) & table_mask;
}
} else {
GEqualFunc equal = hash_table->equal_func;
while (kvs [i].key) {
if (kvs [i].key != TOMBSTONE && equal (key, kvs [i].key)) {
gpointer value;
/* The read of keys must happen before the read of values */
mono_memory_barrier ();
value = kvs [i].value;
/* We just read a value been deleted, try again. */
if (G_UNLIKELY (!value))
goto retry;
mono_hazard_pointer_clear (hp, 0);
return value;
}
i = (i + 1) & table_mask;
}
}
/* The table might have expanded and the value is now on the newer table */
mono_memory_barrier ();
if (hash_table->table != table)
goto retry;
mono_hazard_pointer_clear (hp, 0);
return NULL;
}
static MONO_ALWAYS_INLINE void
insert_one_local (conc_table *table, GHashFunc hash_func, gpointer key, gpointer value)
{
key_value_pair *kvs = table->kvs;
int table_mask = table->table_size - 1;
int hash = mix_hash (hash_func (key));
int i = hash & table_mask;
while (table->kvs [i].key)
i = (i + 1) & table_mask;
kvs [i].key = key;
kvs [i].value = value;
}
static ColorData*
find_in_cache (int *insert_index)
{
HashEntry *bucket;
int i, hash, size, index;
size = dyn_array_ptr_size (&color_merge_array);
/* Cache checking is very ineficient with a lot of elements*/
if (size > 3)
return NULL;
hash = 0;
for (i = 0 ; i < size; ++i)
hash += mix_hash ((size_t)dyn_array_ptr_get (&color_merge_array, i));
if (!hash)
hash = 1;
index = hash & (COLOR_CACHE_SIZE - 1);
bucket = merge_cache [index];
for (i = 0; i < ELEMENTS_PER_BUCKET; ++i) {
if (bucket [i].hash != hash)
continue;
if (match_colors (&bucket [i].color->other_colors, &color_merge_array)) {
++cache_hits;
return bucket [i].color;
}
}
//move elements to the back
for (i = ELEMENTS_PER_BUCKET - 1; i > 0; --i)
bucket [i] = bucket [i - 1];
++cache_misses;
*insert_index = index;
bucket [0].hash = hash;
return NULL;
}
/**
* mono_conc_hashtable_remove:
*
* Remove a value from the hashtable. Requires external locking
*
* @Returns the old value if key is already present or null
*/
gpointer
mono_conc_hashtable_remove (MonoConcurrentHashTable *hash_table, gpointer key)
{
conc_table *table;
key_value_pair *kvs;
int hash, i, table_mask;
g_assert (key != NULL && key != TOMBSTONE);
hash = mix_hash (hash_table->hash_func (key));
table = (conc_table*)hash_table->table;
kvs = table->kvs;
table_mask = table->table_size - 1;
i = hash & table_mask;
if (!hash_table->equal_func) {
for (;;) {
if (!kvs [i].key) {
return NULL; /*key not found*/
}
if (key == kvs [i].key) {
gpointer value = kvs [i].value;
kvs [i].value = NULL;
mono_memory_barrier ();
kvs [i].key = TOMBSTONE;
if (hash_table->key_destroy_func != NULL)
(*hash_table->key_destroy_func) (key);
if (hash_table->value_destroy_func != NULL)
(*hash_table->value_destroy_func) (value);
return value;
}
i = (i + 1) & table_mask;
}
} else {
GEqualFunc equal = hash_table->equal_func;
for (;;) {
if (!kvs [i].key) {
return NULL; /*key not found*/
}
if (kvs [i].key != TOMBSTONE && equal (key, kvs [i].key)) {
gpointer old_key = kvs [i].key;
gpointer value = kvs [i].value;
kvs [i].value = NULL;
mono_memory_barrier ();
kvs [i].key = TOMBSTONE;
if (hash_table->key_destroy_func != NULL)
(*hash_table->key_destroy_func) (old_key);
if (hash_table->value_destroy_func != NULL)
(*hash_table->value_destroy_func) (value);
return value;
}
i = (i + 1) & table_mask;
}
}
}