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authorAndrea Canciani <ranma42@gmail.com>2011-08-02 10:50:51 +0200
committerAndrea Canciani <ranma42@gmail.com>2011-08-03 12:31:41 +0200
commit3fbfa1beed291c58daa56b0a962c30b81c4248cb (patch)
tree5f1797e708f68700c70c0cd4c731ef8d97c9eaa4 /src/cairo-hash.c
parentaaa10fbf125a80e5379172b8564384a945728cba (diff)
hash: Code cleanup
Simplify arrangements by keeping only table sizes, remove some useless code and fix make check.
Diffstat (limited to 'src/cairo-hash.c')
-rw-r--r--src/cairo-hash.c114
1 files changed, 52 insertions, 62 deletions
diff --git a/src/cairo-hash.c b/src/cairo-hash.c
index e36dc6713..f4fb7cdd5 100644
--- a/src/cairo-hash.c
+++ b/src/cairo-hash.c
@@ -80,46 +80,38 @@
* Packard.
*/
-typedef struct _cairo_hash_table_arrangement {
- unsigned long high_water_mark;
- unsigned long size;
- unsigned long rehash;
-} cairo_hash_table_arrangement_t;
-
-static const cairo_hash_table_arrangement_t hash_table_arrangements [] = {
- { 16, 43, 41 },
- { 32, 73, 71 },
- { 64, 151, 149 },
- { 128, 283, 281 },
- { 256, 571, 569 },
- { 512, 1153, 1151 },
- { 1024, 2269, 2267 },
- { 2048, 4519, 4517 },
- { 4096, 9013, 9011 },
- { 8192, 18043, 18041 },
- { 16384, 36109, 36107 },
- { 32768, 72091, 72089 },
- { 65536, 144409, 144407 },
- { 131072, 288361, 288359 },
- { 262144, 576883, 576881 },
- { 524288, 1153459, 1153457 },
- { 1048576, 2307163, 2307161 },
- { 2097152, 4613893, 4613891 },
- { 4194304, 9227641, 9227639 },
- { 8388608, 18455029, 18455027 },
- { 16777216, 36911011, 36911009 },
- { 33554432, 73819861, 73819859 },
- { 67108864, 147639589, 147639587 },
- { 134217728, 295279081, 295279079 },
- { 268435456, 590559793, 590559791 }
+static const unsigned long hash_table_sizes[] = {
+ 43,
+ 73,
+ 151,
+ 283,
+ 571,
+ 1153,
+ 2269,
+ 4519,
+ 9013,
+ 18043,
+ 36109,
+ 72091,
+ 144409,
+ 288361,
+ 576883,
+ 1153459,
+ 2307163,
+ 4613893,
+ 9227641,
+ 18455029,
+ 36911011,
+ 73819861,
+ 147639589,
+ 295279081,
+ 590559793
};
-#define NUM_HASH_TABLE_ARRANGEMENTS ARRAY_LENGTH (hash_table_arrangements)
-
struct _cairo_hash_table {
cairo_hash_keys_equal_func_t keys_equal;
- const cairo_hash_table_arrangement_t *arrangement;
+ const unsigned long *table_size;
cairo_hash_entry_t **entries;
unsigned long live_entries;
@@ -132,7 +124,7 @@ struct _cairo_hash_table {
* @key_a: the first key to be compared
* @key_b: the second key to be compared
*
- * Provides a cairo_hash_keys_equal_func_t which always returns
+ * Provides a #cairo_hash_keys_equal_func_t which always returns
* %TRUE. This is useful to create hash tables using keys whose hash
* completely describes the key, because in this special case
* comparing the hashes is sufficient to guarantee that the keys are
@@ -181,10 +173,10 @@ _cairo_hash_table_create (cairo_hash_keys_equal_func_t keys_equal)
else
hash_table->keys_equal = keys_equal;
- hash_table->arrangement = &hash_table_arrangements[0];
+ hash_table->table_size = &hash_table_sizes[0];
- hash_table->entries = calloc (hash_table->arrangement->size,
- sizeof(cairo_hash_entry_t *));
+ hash_table->entries = calloc (*hash_table->table_size,
+ sizeof (cairo_hash_entry_t *));
if (unlikely (hash_table->entries == NULL)) {
_cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
free (hash_table);
@@ -192,7 +184,7 @@ _cairo_hash_table_create (cairo_hash_keys_equal_func_t keys_equal)
}
hash_table->live_entries = 0;
- hash_table->free_entries = hash_table->arrangement->size;
+ hash_table->free_entries = *hash_table->table_size;
hash_table->iterating = 0;
return hash_table;
@@ -224,8 +216,6 @@ _cairo_hash_table_destroy (cairo_hash_table_t *hash_table)
assert (hash_table->iterating == 0);
free (hash_table->entries);
- hash_table->entries = NULL;
-
free (hash_table);
}
@@ -236,7 +226,7 @@ _cairo_hash_table_lookup_unique_key (cairo_hash_table_t *hash_table,
unsigned long table_size, i, idx, step;
cairo_hash_entry_t **entry;
- table_size = hash_table->arrangement->size;
+ table_size = *hash_table->table_size;
idx = key->hash % table_size;
entry = &hash_table->entries[idx];
@@ -244,7 +234,7 @@ _cairo_hash_table_lookup_unique_key (cairo_hash_table_t *hash_table,
return entry;
i = 1;
- step = 1 + key->hash % hash_table->arrangement->rehash;
+ step = 1 + key->hash % (table_size - 2);
do {
idx += step;
if (idx >= table_size)
@@ -279,7 +269,7 @@ _cairo_hash_table_manage (cairo_hash_table_t *hash_table)
/* Keep between 12.5% and 50% entries in the hash table alive and
* at least 25% free. */
- unsigned long live_high = hash_table->arrangement->size >> 1;
+ unsigned long live_high = *hash_table->table_size >> 1;
unsigned long live_low = live_high >> 2;
unsigned long free_low = live_high >> 1;
@@ -287,21 +277,21 @@ _cairo_hash_table_manage (cairo_hash_table_t *hash_table)
if (hash_table->live_entries > live_high)
{
- tmp.arrangement = hash_table->arrangement + 1;
+ tmp.table_size = hash_table->table_size + 1;
/* This code is being abused if we can't make a table big enough. */
- assert (tmp.arrangement - hash_table_arrangements <
- NUM_HASH_TABLE_ARRANGEMENTS);
+ assert (tmp.table_size - hash_table_sizes <
+ ARRAY_LENGTH (hash_table_sizes));
}
else if (hash_table->live_entries < live_low)
{
/* Can't shrink if we're at the smallest size */
- if (hash_table->arrangement == &hash_table_arrangements[0])
- tmp.arrangement = hash_table->arrangement;
+ if (hash_table->table_size == &hash_table_sizes[0])
+ tmp.table_size = hash_table->table_size;
else
- tmp.arrangement = hash_table->arrangement - 1;
+ tmp.table_size = hash_table->table_size - 1;
}
- if (tmp.arrangement == hash_table->arrangement &&
+ if (tmp.table_size == hash_table->table_size &&
hash_table->free_entries > free_low)
{
/* The number of live entries is within the desired bounds
@@ -310,12 +300,12 @@ _cairo_hash_table_manage (cairo_hash_table_t *hash_table)
return CAIRO_STATUS_SUCCESS;
}
- new_size = tmp.arrangement->size;
+ new_size = *tmp.table_size;
tmp.entries = calloc (new_size, sizeof (cairo_hash_entry_t*));
if (unlikely (tmp.entries == NULL))
return _cairo_error (CAIRO_STATUS_NO_MEMORY);
- for (i = 0; i < hash_table->arrangement->size; ++i) {
+ for (i = 0; i < *hash_table->table_size; ++i) {
if (ENTRY_IS_LIVE (hash_table->entries[i])) {
*_cairo_hash_table_lookup_unique_key (&tmp, hash_table->entries[i])
= hash_table->entries[i];
@@ -324,7 +314,7 @@ _cairo_hash_table_manage (cairo_hash_table_t *hash_table)
free (hash_table->entries);
hash_table->entries = tmp.entries;
- hash_table->arrangement = tmp.arrangement;
+ hash_table->table_size = tmp.table_size;
hash_table->free_entries = new_size - hash_table->live_entries;
return CAIRO_STATUS_SUCCESS;
@@ -348,7 +338,7 @@ _cairo_hash_table_lookup (cairo_hash_table_t *hash_table,
cairo_hash_entry_t *entry;
unsigned long table_size, i, idx, step;
- table_size = hash_table->arrangement->size;
+ table_size = *hash_table->table_size;
idx = key->hash % table_size;
entry = hash_table->entries[idx];
@@ -359,7 +349,7 @@ _cairo_hash_table_lookup (cairo_hash_table_t *hash_table,
return NULL;
i = 1;
- step = 1 + key->hash % hash_table->arrangement->rehash;
+ step = 1 + key->hash % (table_size - 2);
do {
idx += step;
if (idx >= table_size)
@@ -406,7 +396,7 @@ _cairo_hash_table_random_entry (cairo_hash_table_t *hash_table,
assert (predicate != NULL);
- table_size = hash_table->arrangement->size;
+ table_size = *hash_table->table_size;
hash = rand ();
idx = hash % table_size;
@@ -415,7 +405,7 @@ _cairo_hash_table_random_entry (cairo_hash_table_t *hash_table,
return entry;
i = 1;
- step = 1 + hash % hash_table->arrangement->rehash;
+ step = 1 + hash % (table_size - 2);
do {
idx += step;
if (idx >= table_size)
@@ -481,7 +471,7 @@ _cairo_hash_table_lookup_exact_key (cairo_hash_table_t *hash_table,
unsigned long table_size, i, idx, step;
cairo_hash_entry_t **entry;
- table_size = hash_table->arrangement->size;
+ table_size = *hash_table->table_size;
idx = key->hash % table_size;
entry = &hash_table->entries[idx];
@@ -489,7 +479,7 @@ _cairo_hash_table_lookup_exact_key (cairo_hash_table_t *hash_table,
return entry;
i = 1;
- step = 1 + key->hash % hash_table->arrangement->rehash;
+ step = 1 + key->hash % (table_size - 2);
do {
idx += step;
if (idx >= table_size)
@@ -557,7 +547,7 @@ _cairo_hash_table_foreach (cairo_hash_table_t *hash_table,
/* Mark the table for iteration */
++hash_table->iterating;
- for (i = 0; i < hash_table->arrangement->size; i++) {
+ for (i = 0; i < *hash_table->table_size; i++) {
entry = hash_table->entries[i];
if (ENTRY_IS_LIVE(entry))
hash_callback (entry, closure);