python · Fidget-Spinner · Jun 11, 2024 · Jun 11, 2024 · Jun 11, 2024 · Jun 11, 2024
diff --git a/Include/cpython/object.h b/Include/cpython/object.h
@@ -503,6 +503,7 @@ typedef int(*PyType_WatchCallback)(PyTypeObject *);
 PyAPI_FUNC(int) PyType_AddWatcher(PyType_WatchCallback callback);
 PyAPI_FUNC(int) PyType_ClearWatcher(int watcher_id);
 PyAPI_FUNC(int) PyType_Watch(int watcher_id, PyObject *type);
+PyAPI_FUNC(int) PyType_IsWatched(int watcher_id, PyObject *type);
 PyAPI_FUNC(int) PyType_Unwatch(int watcher_id, PyObject *type);
 
 /* Attempt to assign a version tag to the given type.

diff --git a/Include/internal/pycore_opcode_metadata.h b/Include/internal/pycore_opcode_metadata.h
diff --git a/Include/internal/pycore_optimizer.h b/Include/internal/pycore_optimizer.h
@@ -108,13 +108,16 @@ struct _Py_UOpsContext {
     _Py_UopsSymbol **n_consumed;
     _Py_UopsSymbol **limit;
     _Py_UopsSymbol *locals_and_stack[MAX_ABSTRACT_INTERP_SIZE];
+
+    _PyBloomFilter *dependencies;
 };
 
 typedef struct _Py_UOpsContext _Py_UOpsContext;
 
 extern bool _Py_uop_sym_is_null(_Py_UopsSymbol *sym);
 extern bool _Py_uop_sym_is_not_null(_Py_UopsSymbol *sym);
 extern bool _Py_uop_sym_is_const(_Py_UopsSymbol *sym);
+extern bool _Py_uop_sym_is_a_class(_Py_UopsSymbol *sym);
 extern PyObject *_Py_uop_sym_get_const(_Py_UopsSymbol *sym);
 extern _Py_UopsSymbol *_Py_uop_sym_new_unknown(_Py_UOpsContext *ctx);
 extern _Py_UopsSymbol *_Py_uop_sym_new_not_null(_Py_UOpsContext *ctx);
@@ -130,6 +133,7 @@ extern void _Py_uop_sym_set_non_null(_Py_UOpsContext *ctx, _Py_UopsSymbol *sym);
 extern void _Py_uop_sym_set_type(_Py_UOpsContext *ctx, _Py_UopsSymbol *sym, PyTypeObject *typ);
 extern bool _Py_uop_sym_set_type_version(_Py_UOpsContext *ctx, _Py_UopsSymbol *sym, unsigned int version);
 extern void _Py_uop_sym_set_const(_Py_UOpsContext *ctx, _Py_UopsSymbol *sym, PyObject *const_val);
+extern void _Py_uop_sym_set_is_a_class(_Py_UOpsContext *ctx, _Py_UopsSymbol *sym);
 extern bool _Py_uop_sym_is_bottom(_Py_UopsSymbol *sym);
 extern int _Py_uop_sym_truthiness(_Py_UopsSymbol *sym);
 extern PyTypeObject *_Py_uop_sym_get_type(_Py_UopsSymbol *sym);
@@ -150,6 +154,12 @@ PyAPI_FUNC(PyObject *) _Py_uop_symbols_test(PyObject *self, PyObject *ignored);
 
 PyAPI_FUNC(int) _PyOptimizer_Optimize(_PyInterpreterFrame *frame, _Py_CODEUNIT *start, PyObject **stack_pointer, _PyExecutorObject **exec_ptr);
 
+/* The first two dict watcher IDs are reserved for CPython,
+ * so we don't need to check that they haven't been used */
+#define BUILTINS_WATCHER_ID 0
+#define GLOBALS_WATCHER_ID  1
+#define TYPE_WATCHER_ID  0
+
 #ifdef __cplusplus
 }
 #endif

diff --git a/Include/internal/pycore_uop_ids.h b/Include/internal/pycore_uop_ids.h
diff --git a/Include/internal/pycore_uop_metadata.h b/Include/internal/pycore_uop_metadata.h
diff --git a/Lib/test/test_capi/test_opt.py b/Lib/test/test_capi/test_opt.py
@@ -1481,5 +1481,25 @@ def fn(a):
         fn(A())
 
 
+    def test_type_attribute_constant_propagated(self):
+        ns = {}
+        src = textwrap.dedent("""
+            class MyEnum:
+                A = 1
+
+            def testfunc(n):
+                for i in range(n):
+                    x = MyEnum.A
+                    y = MyEnum.A
+        """)
+        exec(src, ns, ns)
+        testfunc = ns['testfunc']
+        _, ex = self._run_with_optimizer(testfunc, TIER2_THRESHOLD * 2)
+        self.assertIsNotNone(ex)
+        uops = get_opnames(ex)
+        self.assertLessEqual(uops.count("_LOAD_ATTR_CLASS_0"), 1)
+        self.assertLessEqual(uops.count("_CHECK_ATTR_CLASS"), 1)
+
+
 if __name__ == "__main__":
     unittest.main()
@@ -956,6 +956,17 @@ PyType_Watch(int watcher_id, PyObject* obj)
     return 0;
 }
 
+int
+PyType_IsWatched(int watcher_id, PyObject* obj)
+{
+    if (!PyType_Check(obj)) {
+        PyErr_SetString(PyExc_ValueError, "Cannot check non-type");
+        return -1;
+    }
+    PyTypeObject *type = (PyTypeObject *)obj;
+    return type->tp_watched & (1 << watcher_id);
+}
+
 int
 PyType_Unwatch(int watcher_id, PyObject* obj)
 {

@@ -2036,10 +2036,9 @@ dummy_func(
             unused/5;
 
         op(_CHECK_ATTR_CLASS, (type_version/2, owner -- owner)) {
-            DEOPT_IF(!PyType_Check(owner));
+            EXIT_IF(!PyType_Check(owner));
             assert(type_version != 0);
-            DEOPT_IF(((PyTypeObject *)owner)->tp_version_tag != type_version);
-
+            EXIT_IF(((PyTypeObject *)owner)->tp_version_tag != type_version);
         }
 
         split op(_LOAD_ATTR_CLASS, (descr/4, owner -- attr, null if (oparg & 1))) {
@@ -4239,6 +4238,11 @@ dummy_func(
             value = Py_NewRef(ptr);
         }
 
+        tier2 pure op (_POP_TOP_LOAD_CONST_INLINE, (ptr/4, pop -- value)) {
+            Py_DECREF(pop);
+            value = Py_NewRef(ptr);
+        }
+
         tier2 pure op(_LOAD_CONST_INLINE_BORROW, (ptr/4 -- value)) {
             value = ptr;
         }
@@ -4253,6 +4257,12 @@ dummy_func(
             null = NULL;
         }
 
+        tier2 pure op(_POP_TOP_LOAD_CONST_INLINE_WITH_NULL, (ptr/4, pop -- value, null)) {
+            Py_DECREF(pop);
+            value = Py_NewRef(ptr);
+            null = NULL;
+        }
+
         tier2 pure op(_LOAD_CONST_INLINE_BORROW_WITH_NULL, (ptr/4 -- value, null)) {
             value = ptr;
             null = NULL;

diff --git a/Python/executor_cases.c.h b/Python/executor_cases.c.h