Simple optimization by Christian Tismer, who gives credit to Lenny

Kneler for reporting this issue: long_mult() is faster when the
smaller argument is on the left.  Swap the arguments accordingly.

1 files changed, 9 insertions, 0 deletions

diff --git a/Objects/longobject.c b/Objects/longobject.c
index d5c2f5f..a9ce6f3 100644
--- a/Objects/longobject.c
+++ b/Objects/longobject.c
@@ -1223,6 +1223,15 @@ long_mul(a, b)
 	
 	size_a = ABS(a->ob_size);
 	size_b = ABS(b->ob_size);
+	if (size_a > size_b) {
+		/* we are faster with the small object on the left */
+		int hold_sa = size_a;
+		PyLongObject *hold_a = a;
+		size_a = size_b;
+		size_b = hold_sa;
+		a = b;
+		b = hold_a;
+	}
 	z = _PyLong_New(size_a + size_b);
 	if (z == NULL)
 		return NULL;