speed up __Pyx_PySet_Update() a little by calling it as an unbound method

Cython/Compiler/Code.py

@@ -438,7 +438,7 @@ class UtilityCode(UtilityCodeBase):
             replacements.append(cname)
             return '%s(&%s, %s)' % (call, cname, ', '.join(args))
 
-        impl = re.sub(r'CALL_UNBOUND_METHOD\(([a-zA-Z_]+),\s*"([^"]+)"(,\s*[^),]+)+\)', externalise, impl)
+        impl = re.sub(r'CALL_UNBOUND_METHOD\(([a-zA-Z_]+),\s*"([^"]+)"((?:,\s*[^),]+)+)\)', externalise, impl)
         assert 'CALL_UNBOUND_METHOD(' not in impl
         return bool(replacements), impl
 

Cython/Utility/Builtins.c

@@ -477,7 +477,7 @@ static CYTHON_INLINE int __Pyx_PySet_Update(PyObject* set, PyObject* it) {
         Py_DECREF(retval);
     }
     #endif
-    retval = __Pyx_PyObject_CallMethod1(set, PYIDENT("update"), it);
+    retval = CALL_UNBOUND_METHOD(PySet_Type, "update", set, it);
     if (unlikely(!retval)) return -1;
     Py_DECREF(retval);
     return 0;