Variation of patch # 1624059 to speed up checking if an object is a subclass

of some of the common builtin types.

Use a bit in tp_flags for each common builtin type.  Check the bit
to determine if any instance is a subclass of these common types.
The check avoids a function call and O(n) search of the base classes.
The check is done in the various Py*_Check macros rather than calling
PyType_IsSubtype().

All the bits are set in tp_flags when the type is declared
in the Objects/*object.c files because PyType_Ready() is not called
for all the types.  Should PyType_Ready() be called for all types?
If so and the change is made, the changes to the Objects/*object.c files
can be reverted (remove setting the tp_flags).  Objects/typeobject.c
would also have to be modified to add conditions
for Py*_CheckExact() in addition to each the PyType_IsSubtype check.

9 files changed, 31 insertions, 13 deletions

diff --git a/Include/dictobject.h b/Include/dictobject.h
index 44b0838..ec2e0c8 100644
--- a/Include/dictobject.h
+++ b/Include/dictobject.h
@@ -90,7 +90,8 @@ struct _dictobject {
 
 PyAPI_DATA(PyTypeObject) PyDict_Type;
 
-#define PyDict_Check(op) PyObject_TypeCheck(op, &PyDict_Type)
+#define PyDict_Check(op) \
+                 PyType_FastSubclass((op)->ob_type, Py_TPFLAGS_DICT_SUBCLASS)
 #define PyDict_CheckExact(op) ((op)->ob_type == &PyDict_Type)
 
 PyAPI_FUNC(PyObject *) PyDict_New(void);
diff --git a/Include/intobject.h b/Include/intobject.h
index 1f4846e..51d3e1b 100644
--- a/Include/intobject.h
+++ b/Include/intobject.h
@@ -27,7 +27,8 @@ typedef struct {
 
 PyAPI_DATA(PyTypeObject) PyInt_Type;
 
-#define PyInt_Check(op) PyObject_TypeCheck(op, &PyInt_Type)
+#define PyInt_Check(op) \
+		 PyType_FastSubclass((op)->ob_type, Py_TPFLAGS_INT_SUBCLASS)
 #define PyInt_CheckExact(op) ((op)->ob_type == &PyInt_Type)
 
 PyAPI_FUNC(PyObject *) PyInt_FromString(char*, char**, int);
diff --git a/Include/listobject.h b/Include/listobject.h
index d9012ce..db3124e 100644
--- a/Include/listobject.h
+++ b/Include/listobject.h
@@ -40,7 +40,8 @@ typedef struct {
 
 PyAPI_DATA(PyTypeObject) PyList_Type;
 
-#define PyList_Check(op) PyObject_TypeCheck(op, &PyList_Type)
+#define PyList_Check(op) \
+		PyType_FastSubclass((op)->ob_type, Py_TPFLAGS_LIST_SUBCLASS)
 #define PyList_CheckExact(op) ((op)->ob_type == &PyList_Type)
 
 PyAPI_FUNC(PyObject *) PyList_New(Py_ssize_t size);
diff --git a/Include/longobject.h b/Include/longobject.h
index eef4e9b..3893ad6 100644
--- a/Include/longobject.h
+++ b/Include/longobject.h
@@ -11,7 +11,8 @@ typedef struct _longobject PyLongObject; /* Revealed in longintrepr.h */
 
 PyAPI_DATA(PyTypeObject) PyLong_Type;
 
-#define PyLong_Check(op) PyObject_TypeCheck(op, &PyLong_Type)
+#define PyLong_Check(op) \
+		PyType_FastSubclass((op)->ob_type, Py_TPFLAGS_LONG_SUBCLASS)
 #define PyLong_CheckExact(op) ((op)->ob_type == &PyLong_Type)
 
 PyAPI_FUNC(PyObject *) PyLong_FromLong(long);
diff --git a/Include/object.h b/Include/object.h
index b0817e6..0f6ff77 100644
--- a/Include/object.h
+++ b/Include/object.h
@@ -376,7 +376,8 @@ PyAPI_DATA(PyTypeObject) PyType_Type; /* built-in 'type' */
 PyAPI_DATA(PyTypeObject) PyBaseObject_Type; /* built-in 'object' */
 PyAPI_DATA(PyTypeObject) PySuper_Type; /* built-in 'super' */
 
-#define PyType_Check(op) PyObject_TypeCheck(op, &PyType_Type)
+#define PyType_Check(op) \
+	PyType_FastSubclass((op)->ob_type, Py_TPFLAGS_TYPE_SUBCLASS)
 #define PyType_CheckExact(op) ((op)->ob_type == &PyType_Type)
 
 PyAPI_FUNC(int) PyType_Ready(PyTypeObject *);
@@ -517,6 +518,17 @@ given type object has a specified feature.
 /* Objects support nb_index in PyNumberMethods */
 #define Py_TPFLAGS_HAVE_INDEX (1L<<17)
 
+/* These flags are used to determine if a type is a subclass. */
+#define Py_TPFLAGS_INT_SUBCLASS		(1L<<23)
+#define Py_TPFLAGS_LONG_SUBCLASS	(1L<<24)
+#define Py_TPFLAGS_LIST_SUBCLASS	(1L<<25)
+#define Py_TPFLAGS_TUPLE_SUBCLASS	(1L<<26)
+#define Py_TPFLAGS_STRING_SUBCLASS	(1L<<27)
+#define Py_TPFLAGS_UNICODE_SUBCLASS	(1L<<28)
+#define Py_TPFLAGS_DICT_SUBCLASS	(1L<<29)
+#define Py_TPFLAGS_BASE_EXC_SUBCLASS	(1L<<30)
+#define Py_TPFLAGS_TYPE_SUBCLASS	(1L<<31)
+
 #define Py_TPFLAGS_DEFAULT  ( \
                              Py_TPFLAGS_HAVE_GETCHARBUFFER | \
                              Py_TPFLAGS_HAVE_SEQUENCE_IN | \
@@ -530,6 +542,7 @@ given type object has a specified feature.
                             0)
 
 #define PyType_HasFeature(t,f)  (((t)->tp_flags & (f)) != 0)
+#define PyType_FastSubclass(t,f)  PyType_HasFeature(t,f)
 
 
 /*
diff --git a/Include/pyerrors.h b/Include/pyerrors.h
index 9532e32..9671692 100644
--- a/Include/pyerrors.h
+++ b/Include/pyerrors.h
@@ -95,14 +95,12 @@ PyAPI_FUNC(void) PyErr_NormalizeException(PyObject**, PyObject**, PyObject**);
 /* */
 
 #define PyExceptionClass_Check(x)					\
-	(PyClass_Check((x))						\
-	 || (PyType_Check((x)) && PyType_IsSubtype(			\
-		     (PyTypeObject*)(x), (PyTypeObject*)PyExc_BaseException)))
-
+	(PyClass_Check((x)) || (PyType_Check((x)) &&			\
+	  PyType_FastSubclass((PyTypeObject*)(x), Py_TPFLAGS_BASE_EXC_SUBCLASS)))
 
 #define PyExceptionInstance_Check(x)			\
 	(PyInstance_Check((x)) ||			\
-	 (PyType_IsSubtype((x)->ob_type, (PyTypeObject*)PyExc_BaseException)))
+	 PyType_FastSubclass((x)->ob_type, Py_TPFLAGS_BASE_EXC_SUBCLASS))
 
 #define PyExceptionClass_Name(x)				   \
 	(PyClass_Check((x))					   \
diff --git a/Include/stringobject.h b/Include/stringobject.h
index 5f8a6f0..03c3777 100644
--- a/Include/stringobject.h
+++ b/Include/stringobject.h
@@ -55,7 +55,8 @@ typedef struct {
 PyAPI_DATA(PyTypeObject) PyBaseString_Type;
 PyAPI_DATA(PyTypeObject) PyString_Type;
 
-#define PyString_Check(op) PyObject_TypeCheck(op, &PyString_Type)
+#define PyString_Check(op) \
+                 PyType_FastSubclass((op)->ob_type, Py_TPFLAGS_STRING_SUBCLASS)
 #define PyString_CheckExact(op) ((op)->ob_type == &PyString_Type)
 
 PyAPI_FUNC(PyObject *) PyString_FromStringAndSize(const char *, Py_ssize_t);
diff --git a/Include/tupleobject.h b/Include/tupleobject.h
index 8c37cab..738cea1 100644
--- a/Include/tupleobject.h
+++ b/Include/tupleobject.h
@@ -33,7 +33,8 @@ typedef struct {
 
 PyAPI_DATA(PyTypeObject) PyTuple_Type;
 
-#define PyTuple_Check(op) PyObject_TypeCheck(op, &PyTuple_Type)
+#define PyTuple_Check(op) \
+                 PyType_FastSubclass((op)->ob_type, Py_TPFLAGS_TUPLE_SUBCLASS)
 #define PyTuple_CheckExact(op) ((op)->ob_type == &PyTuple_Type)
 
 PyAPI_FUNC(PyObject *) PyTuple_New(Py_ssize_t size);
diff --git a/Include/unicodeobject.h b/Include/unicodeobject.h
index 33aa185..0bad8c3 100644
--- a/Include/unicodeobject.h
+++ b/Include/unicodeobject.h
@@ -392,7 +392,8 @@ typedef struct {
 
 PyAPI_DATA(PyTypeObject) PyUnicode_Type;
 
-#define PyUnicode_Check(op) PyObject_TypeCheck(op, &PyUnicode_Type)
+#define PyUnicode_Check(op) \
+                 PyType_FastSubclass((op)->ob_type, Py_TPFLAGS_UNICODE_SUBCLASS)
 #define PyUnicode_CheckExact(op) ((op)->ob_type == &PyUnicode_Type)
 
 /* Fast access macros */