[hash] Set is_unique when finding an available for inserts

As we obey the rule in Cairo that we only insert if we know that there is
no existing entry in the hash table, we can therefore perform a much quicker
search knowing that the key is unique.

1 files changed, 7 insertions, 9 deletions

diff --git a/src/cairo-hash.c b/src/cairo-hash.c
index 2317eb17..41abafd6 100644
--- a/src/cairo-hash.c
+++ b/src/cairo-hash.c
@@ -448,8 +448,8 @@ _cairo_hash_table_random_entry (cairo_hash_table_t	   *hash_table,
  *
  * Insert the entry #key_and_value into the hash table.
  *
- * WARNING: It is a fatal error if an entry exists in the hash table
- * with a matching key, (this function will halt).
+ * WARNING: There must not be an existing entry in the hash table
+ * with a matching key.
  *
  * WARNING: It is a fatal error to insert an element while
  * an iterator is running
@@ -472,13 +472,11 @@ _cairo_hash_table_insert (cairo_hash_table_t *hash_table,
     assert (hash_table->iterating == 0);
 
     entry = _cairo_hash_table_lookup_internal (hash_table,
-					       key_and_value, FALSE);
-
-    if (ENTRY_IS_LIVE(*entry))
-    {
-	/* User is being bad, let's crash. */
-	ASSERT_NOT_REACHED;
-    }
+					       key_and_value,
+					       TRUE);
+    /* _cairo_hash_table_lookup_internal with key_unique = TRUE
+     * aways returns an available entry. */
+    assert (! ENTRY_IS_LIVE(*entry));
 
     *entry = key_and_value;
     hash_table->live_entries++;