From: Guido van Rossum <guido@python.org>
Date: Mon, 10 Apr 2000 17:31:58 +0000 (+0000)
Subject: Simple optimization by Christian Tismer, who gives credit to Lenny
X-Git-Tag: v1.6a2~34
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=ba71a247acc7cac07a75d79ff087b29b56ee0b55;p=python

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.
---

diff --git a/Objects/longobject.c b/Objects/longobject.c
index d5c2f5f767..a9ce6f3c3b 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;