From: Guido van Rossum <guido@python.org>
Date: Mon, 19 Aug 2002 16:02:33 +0000 (+0000)
Subject: Simple but important optimization for descr_check(): instead of the
X-Git-Tag: v2.3c1~4409
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=c588e9041aea212fe2b5fad9254824d12f804c3e;p=python

Simple but important optimization for descr_check(): instead of the
expensive and overly general PyObject_IsInstance(), call
PyObject_TypeCheck() which is a macro that often avoids a call, and if
it does make a call, calls the much more efficient PyType_IsSubtype().
This saved 6% on a benchmark for slot lookups.
---

diff --git a/Objects/descrobject.c b/Objects/descrobject.c
index cbf9e16113..6daffc6175 100644
--- a/Objects/descrobject.c
+++ b/Objects/descrobject.c
@@ -65,7 +65,7 @@ descr_check(PyDescrObject *descr, PyObject *obj, PyTypeObject *type,
 		*pres = (PyObject *)descr;
 		return 1;
 	}
-	if (!PyObject_IsInstance(obj, (PyObject *)(descr->d_type))) {
+	if (!PyObject_TypeCheck(obj, descr->d_type)) {
 		PyErr_Format(PyExc_TypeError,
 			     "descriptor '%s' for '%s' objects "
 			     "doesn't apply to '%s' object",