diff options
Diffstat (limited to 'libihash/ihash.c')
| -rw-r--r-- | libihash/ihash.c | 22 |
1 files changed, 4 insertions, 18 deletions
diff --git a/libihash/ihash.c b/libihash/ihash.c index 4d9cc18e..fa29257b 100644 --- a/libihash/ihash.c +++ b/libihash/ihash.c @@ -32,19 +32,6 @@ #include "ihash.h" -/* This is the integer finalizer from MurmurHash3. */ -static inline uint32_t -murmur3_mix32 (uint32_t h, unsigned int bits) -{ - h ^= h >> 16; - h *= 0x85ebca6b; - h ^= h >> 13; - h *= 0xc2b2ae35; - h ^= h >> 16; - - return h >> (32 - bits); -} - /* Return 1 if the slot with the index IDX in the hash table HT is empty, and 0 otherwise. */ static inline int @@ -74,7 +61,7 @@ find_index (hurd_ihash_t ht, hurd_ihash_key_t key) unsigned int up_idx; unsigned int mask = ht->size - 1; - idx = murmur3_mix32 (key, __builtin_ctzl (ht->size)); + idx = key & mask; if (ht->items[idx].value == _HURD_IHASH_EMPTY || ht->items[idx].key == key) return idx; @@ -205,20 +192,19 @@ hurd_ihash_set_max_load (hurd_ihash_t ht, unsigned int max_load) found. The arguments are identical to hurd_ihash_add. We are using open address hashing. As the hash function we use the - division method with quadratic probe. This is guaranteed to try - all slots in the hash table if the prime number is 3 mod 4. */ + division method with linear probe. */ static inline int add_one (hurd_ihash_t ht, hurd_ihash_key_t key, hurd_ihash_value_t value) { unsigned int idx; unsigned int first_free; + unsigned int mask = ht->size - 1; - idx = murmur3_mix32 (key, __builtin_ctzl (ht->size)); + idx = key & mask; first_free = idx; if (ht->items[idx].value != _HURD_IHASH_EMPTY && ht->items[idx].key != key) { - unsigned int mask = ht->size - 1; unsigned int up_idx = idx; do |