commit 793426687509be24a42663a27e568cc92dcc07f6
author Serhiy Storchaka <storchaka@gmail.com> Sat Jan 12 08:25:41 2019 +0200
committer GitHub <noreply@github.com> Sat Jan 12 08:25:41 2019 +0200
tree 905154eb18d4d654b3c0d295f571b96e6250c75b
parent cb08a71c5c534f33d9486677534dafb087c30e8c

bpo-35582: Inline arguments tuple unpacking in handwritten code. (GH-11524)

Inline PyArg_UnpackTuple() and _PyArg_UnpackStack() in performance
sensitive code in the builtins and operator modules.

Modules/_operator.c

diff --git a/Modules/_operator.c b/Modules/_operator.c
index d6c6a18..d291ec1 100644
--- a/Modules/_operator.c
+++ b/Modules/_operator.c
@@ -1011,15 +1011,12 @@
     Py_ssize_t i, nitems=ig->nitems;
 
     assert(PyTuple_CheckExact(args));
-    if (kw == NULL && PyTuple_GET_SIZE(args) == 1) {
-        obj = PyTuple_GET_ITEM(args, 0);
-    }
-    else {
-        if (!_PyArg_NoKeywords("itemgetter", kw))
-            return NULL;
-        if (!PyArg_UnpackTuple(args, "itemgetter", 1, 1, &obj))
-            return NULL;
-    }
+    if (!_PyArg_NoKeywords("itemgetter", kw))
+        return NULL;
+    if (!_PyArg_CheckPositional("itemgetter", PyTuple_GET_SIZE(args), 1, 1))
+        return NULL;
+
+    obj = PyTuple_GET_ITEM(args, 0);
     if (nitems == 1) {
         if (ig->index >= 0
             && PyTuple_CheckExact(obj)
@@ -1317,8 +1314,9 @@
 
     if (!_PyArg_NoKeywords("attrgetter", kw))
         return NULL;
-    if (!PyArg_UnpackTuple(args, "attrgetter", 1, 1, &obj))
+    if (!_PyArg_CheckPositional("attrgetter", PyTuple_GET_SIZE(args), 1, 1))
         return NULL;
+    obj = PyTuple_GET_ITEM(args, 0);
     if (ag->nattrs == 1) /* ag->attr is always a tuple */
         return dotted_getattr(obj, PyTuple_GET_ITEM(ag->attr, 0));
 
@@ -1561,8 +1559,9 @@
 
     if (!_PyArg_NoKeywords("methodcaller", kw))
         return NULL;
-    if (!PyArg_UnpackTuple(args, "methodcaller", 1, 1, &obj))
+    if (!_PyArg_CheckPositional("methodcaller", PyTuple_GET_SIZE(args), 1, 1))
         return NULL;
+    obj = PyTuple_GET_ITEM(args, 0);
     method = PyObject_GetAttr(obj, mc->name);
     if (method == NULL)
         return NULL;