Use Timsort for sorting

Zend/zend_sort.c

@@ -312,7 +312,7 @@ ZEND_API void zend_insert_sort(void *base, size_t nmemb, size_t siz, compare_fun
  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  * IN THE SOFTWARE.
  */
-ZEND_API void zend_sort(void *base, size_t nmemb, size_t siz, compare_func_t cmp, swap_func_t swp)
+ZEND_API void zend_sort_unstable(void *base, size_t nmemb, size_t siz, compare_func_t cmp, swap_func_t swp)
 {
 	while (1) {
 		if (nmemb <= 16) {
@@ -372,3 +372,53 @@ ZEND_API void zend_sort(void *base, size_t nmemb, size_t siz, compare_func_t cmp
 	}
 }
 /* }}} */
+
+/**
+ * A stable, adaptive, iterative mergesort that requires far fewer than
+ * n lg(n) comparisons when running on partially sorted arrays, while
+ * offering performance comparable to a traditional mergesort when run
+ * on random arrays.  Like all proper mergesorts, this sort is stable and
+ * runs O(n log n) time (worst case).  In the worst case, this sort requires
+ * temporary storage space for n/2 object references; in the best case,
+ * it requires only a small constant amount of space.
+ *
+ * This implementation was adapted from Josh Bloch's Java implementation of
+ * Tim Peters's list sort for Python, which is described in detail here:
+ *
+ *   http://svn.python.org/projects/python/trunk/Objects/listsort.txt
+ *
+ * Tim's C code may be found here:
+ *
+ *   http://svn.python.org/projects/python/trunk/Objects/listobject.c
+ *
+ * Josh's (Apache 2.0 Licenced) Java code may be found here:
+ *
+ *   http://gee.cs.oswego.edu/cgi-bin/viewcvs.cgi/jsr166/src/main/java/util/TimSort.java?view=co
+ *
+ * The underlying techniques are described in this paper (and may have
+ * even earlier origins):
+ *
+ *  "Optimistic Sorting and Information Theoretic Complexity"
+ *  Peter McIlroy
+ *  SODA (Fourth Annual ACM-SIAM Symposium on Discrete Algorithms),
+ *  pp 467-474, Austin, Texas, 25-27 January 1993.
+ *
+ * While the API to this class consists solely of static methods, it is
+ * (privately) instantiable; a TimSort instance holds the state of an ongoing
+ * sort, assuming the input array is large enough to warrant the full-blown
+ * TimSort. Small arrays are sorted in place, using a binary insertion sort.
+ *
+ * @author Josh Bloch
+ * @author Patrick O. Perry
+ */
+int zend_timsort(
+	void *base, size_t nel, size_t width, int (*compar) (const void *, const void *));
+
+int zend_timsort_r(
+	void *base, size_t nel, size_t width, int (*compar) (const void *, const void *, void *),
+	void *context);
+
+ZEND_API void zend_sort(void *base, size_t nmemb, size_t siz, compare_func_t cmp, swap_func_t swp)
+{
+	zend_timsort(base, nmemb, siz, cmp);
+}