Optimise attribute access on Cython provided extension types without instance...

Optimise attribute access on Cython provided extension types without instance dict through a streamlined copy of "PyObject_GenericGetAttr".

Cython/Utility/AsyncGen.c

@@ -104,7 +104,7 @@ static int __Pyx_async_gen_init_hooks(__pyx_PyAsyncGenObject *o) {
 //@requires: Coroutine.c::Coroutine
 //@requires: Coroutine.c::ReturnWithStopIteration
 //@requires: ObjectHandling.c::PyObjectCallMethod1
-
+//@requires: ObjectHandling.c::PyObject_GenericGetAttrNoDict
 
 PyDoc_STRVAR(__Pyx_async_gen_send_doc,
 "send(arg) -> send 'arg' into generator,\n\
@@ -1041,10 +1041,10 @@ __Pyx_async_gen_athrow_new(__pyx_PyAsyncGenObject *gen, PyObject *args)
 
 static int __pyx_AsyncGen_init(void) {
     // on Windows, C-API functions can't be used in slots statically
-    __pyx_AsyncGenType_type.tp_getattro = PyObject_GenericGetAttr;
-    __pyx__PyAsyncGenWrappedValueType_type.tp_getattro = PyObject_GenericGetAttr;
-    __pyx__PyAsyncGenAThrowType_type.tp_getattro = PyObject_GenericGetAttr;
-    __pyx__PyAsyncGenASendType_type.tp_getattro = PyObject_GenericGetAttr;
+    __pyx_AsyncGenType_type.tp_getattro = __Pyx_PyObject_GenericGetAttrNoDict;
+    __pyx__PyAsyncGenWrappedValueType_type.tp_getattro = __Pyx_PyObject_GenericGetAttrNoDict;
+    __pyx__PyAsyncGenAThrowType_type.tp_getattro = __Pyx_PyObject_GenericGetAttrNoDict;
+    __pyx__PyAsyncGenASendType_type.tp_getattro = __Pyx_PyObject_GenericGetAttrNoDict;
 
     __pyx_AsyncGenType = __Pyx_FetchCommonType(&__pyx_AsyncGenType_type);
     if (unlikely(!__pyx_AsyncGenType))

Cython/Utility/Coroutine.c

@@ -1335,6 +1335,7 @@ static __pyx_CoroutineObject *__Pyx__Coroutine_NewInit(
 //////////////////// Coroutine ////////////////////
 //@requires: CoroutineBase
 //@requires: PatchGeneratorABC
+//@requires: ObjectHandling.c::PyObject_GenericGetAttrNoDict
 
 static void __Pyx_CoroutineAwait_dealloc(PyObject *self) {
     PyObject_GC_UnTrack(self);
@@ -1597,10 +1598,10 @@ static PyTypeObject __pyx_CoroutineType_type = {
 
 static int __pyx_Coroutine_init(void) {
     // on Windows, C-API functions can't be used in slots statically
-    __pyx_CoroutineType_type.tp_getattro = PyObject_GenericGetAttr;
+    __pyx_CoroutineType_type.tp_getattro = __Pyx_PyObject_GenericGetAttrNoDict;
 
 #ifdef __Pyx_IterableCoroutine_USED
-    __pyx_IterableCoroutineType_type.tp_getattro = PyObject_GenericGetAttr;
+    __pyx_IterableCoroutineType_type.tp_getattro = __Pyx_PyObject_GenericGetAttrNoDict;
     __pyx_IterableCoroutineType = __Pyx_FetchCommonType(&__pyx_IterableCoroutineType_type);
     if (unlikely(!__pyx_IterableCoroutineType))
         return -1;
@@ -1705,6 +1706,7 @@ static PyTypeObject __pyx_IterableCoroutineType_type = {
 //////////////////// Generator ////////////////////
 //@requires: CoroutineBase
 //@requires: PatchGeneratorABC
+//@requires: ObjectHandling.c::PyObject_GenericGetAttrNoDict
 
 static PyMethodDef __pyx_Generator_methods[] = {
     {"send", (PyCFunction) __Pyx_Coroutine_Send, METH_O,
@@ -1793,7 +1795,7 @@ static PyTypeObject __pyx_GeneratorType_type = {
 
 static int __pyx_Generator_init(void) {
     // on Windows, C-API functions can't be used in slots statically
-    __pyx_GeneratorType_type.tp_getattro = PyObject_GenericGetAttr;
+    __pyx_GeneratorType_type.tp_getattro = __Pyx_PyObject_GenericGetAttrNoDict;
     __pyx_GeneratorType_type.tp_iter = PyObject_SelfIter;
 
     __pyx_GeneratorType = __Pyx_FetchCommonType(&__pyx_GeneratorType_type);

Cython/Utility/ObjectHandling.c

@@ -1226,7 +1226,82 @@ static CYTHON_INLINE PyObject* __Pyx_PyObject_LookupSpecial(PyObject* obj, PyObj
 #define __Pyx_PyObject_LookupSpecial(o,n) __Pyx_PyObject_GetAttrStr(o,n)
 #endif
 
-/////////////// PyObjectGetAttrStr.proto ///////////////
+
+/////////////// PyObject_GenericGetAttrNoDict.proto ///////////////
+
+#if CYTHON_USE_TYPE_SLOTS && CYTHON_USE_PYTYPE_LOOKUP
+static PyObject* __Pyx_PyObject_GenericGetAttrNoDict(PyObject* obj, PyObject* attr_name);
+#else
+// No-args macro to allow function pointer assignment.
+#define __Pyx_PyObject_GenericGetAttrNoDict PyObject_GenericGetAttr
+#endif
+
+/////////////// PyObject_GenericGetAttrNoDict ///////////////
+
+#if CYTHON_USE_TYPE_SLOTS && CYTHON_USE_PYTYPE_LOOKUP
+
+static PyObject *__Pyx_RaiseGenericAttributeError(PyTypeObject *tp, PyObject *attr_name) {
+    PyErr_Format(PyExc_AttributeError,
+#if PY_MAJOR_VERSION >= 3
+                 "'%.50s' object has no attribute '%U'",
+                 tp->tp_name, attr_name);
+#else
+                 "'%.50s' object has no attribute '%.400s'",
+                 tp->tp_name, PyString_AS_STRING(attr_name));
+#endif
+    return NULL;
+}
+
+static PyObject* __Pyx_PyObject_GenericGetAttrNoDict(PyObject* obj, PyObject* attr_name) {
+    // Copied and adapted from _PyObject_GenericGetAttrWithDict() in CPython 2.6/3.7.
+    // To be used in the "tp_getattro" slot of extension types that have no instance dict and cannot be subclassed.
+    PyObject *descr, *res;
+    PyTypeObject *tp = Py_TYPE(obj);
+    descrgetfunc f = NULL;
+
+    if (unlikely(!PyString_Check(attr_name))) {
+        return PyObject_GenericGetAttr(obj, attr_name);
+    }
+
+    assert(!tp->tp_dictoffset);
+    descr = _PyType_Lookup(tp, attr_name);
+    if (descr
+        #if PY_MAJOR_VERSION < 3
+            && likely(PyType_HasFeature(Py_TYPE(descr), Py_TPFLAGS_HAVE_CLASS))
+        #endif
+            ) {
+        f = Py_TYPE(descr)->tp_descr_get;
+        // Optimise for the non-descriptor case because it is faster.
+        if (unlikely(f)) {
+            Py_INCREF(descr);
+            res = f(descr, obj, (PyObject *)tp);
+            Py_DECREF(descr);
+            goto done;
+        }
+    }
+    if (likely(descr)) {
+        Py_INCREF(descr);
+        res = descr;
+        goto done;
+    }
+
+    return __Pyx_RaiseGenericAttributeError(tp, attr_name);
+done:
+    return res;
+}
+// CYTHON_USE_PYTYPE_LOOKUP
+#endif
+
+
+////////////// PyObjectGetAttrStr.proto ///////////////
+
+#if CYTHON_USE_TYPE_SLOTS
+static CYTHON_INLINE PyObject* __Pyx_PyObject_GetAttrStr(PyObject* obj, PyObject* attr_name);/*proto*/
+#else
+#define __Pyx_PyObject_GetAttrStr(o,n) PyObject_GetAttr(o,n)
+#endif
+
+/////////////// PyObjectGetAttrStr ///////////////
 
 #if CYTHON_USE_TYPE_SLOTS
 static CYTHON_INLINE PyObject* __Pyx_PyObject_GetAttrStr(PyObject* obj, PyObject* attr_name) {
@@ -1239,14 +1314,22 @@ static CYTHON_INLINE PyObject* __Pyx_PyObject_GetAttrStr(PyObject* obj, PyObject
 #endif
     return PyObject_GetAttr(obj, attr_name);
 }
-#else
-#define __Pyx_PyObject_GetAttrStr(o,n) PyObject_GetAttr(o,n)
 #endif
 
+
 /////////////// PyObjectSetAttrStr.proto ///////////////
 
 #if CYTHON_USE_TYPE_SLOTS
-#define __Pyx_PyObject_DelAttrStr(o,n) __Pyx_PyObject_SetAttrStr(o,n,NULL)
+#define __Pyx_PyObject_DelAttrStr(o,n) __Pyx_PyObject_SetAttrStr(o, n, NULL)
+static CYTHON_INLINE int __Pyx_PyObject_SetAttrStr(PyObject* obj, PyObject* attr_name, PyObject* value);/*proto*/
+#else
+#define __Pyx_PyObject_DelAttrStr(o,n)   PyObject_DelAttr(o,n)
+#define __Pyx_PyObject_SetAttrStr(o,n,v) PyObject_SetAttr(o,n,v)
+#endif
+
+/////////////// PyObjectSetAttrStr ///////////////
+
+#if CYTHON_USE_TYPE_SLOTS
 static CYTHON_INLINE int __Pyx_PyObject_SetAttrStr(PyObject* obj, PyObject* attr_name, PyObject* value) {
     PyTypeObject* tp = Py_TYPE(obj);
     if (likely(tp->tp_setattro))
@@ -1257,9 +1340,6 @@ static CYTHON_INLINE int __Pyx_PyObject_SetAttrStr(PyObject* obj, PyObject* attr
 #endif
     return PyObject_SetAttr(obj, attr_name, value);
 }
-#else
-#define __Pyx_PyObject_DelAttrStr(o,n)   PyObject_DelAttr(o,n)
-#define __Pyx_PyObject_SetAttrStr(o,n,v) PyObject_SetAttr(o,n,v)
 #endif