Modernize LOAD_ATTR_METHOD_NO_DICT

Author: gvanrossum

Python/bytecodes.c

@@ -1446,7 +1446,7 @@ dummy_func(
             LOAD_ATTR_PROPERTY,
             LOAD_ATTR_GETATTRIBUTE_OVERRIDDEN,
             LOAD_ATTR_METHOD_WITH_VALUES,
-            // LOAD_ATTR_METHOD_NO_DICT,
+            LOAD_ATTR_METHOD_NO_DICT,
             // LOAD_ATTR_METHOD_LAZY_DICT,
         };
 
@@ -2359,22 +2359,17 @@ dummy_func(
             assert(oparg & 1);
         }
 
-        // error: LOAD_ATTR has irregular stack effect
-        inst(LOAD_ATTR_METHOD_NO_DICT) {
+        inst(LOAD_ATTR_METHOD_NO_DICT, (unused/1, type_version/2, unused/2, descr/4, self -- res2 if (oparg & 1), res)) {
             assert(cframe.use_tracing == 0);
-            PyObject *self = TOP();
             PyTypeObject *self_cls = Py_TYPE(self);
-            _PyLoadMethodCache *cache = (_PyLoadMethodCache *)next_instr;
-            uint32_t type_version = read_u32(cache->type_version);
             DEOPT_IF(self_cls->tp_version_tag != type_version, LOAD_ATTR);
             assert(self_cls->tp_dictoffset == 0);
             STAT_INC(LOAD_ATTR, hit);
-            PyObject *res = read_obj(cache->descr);
-            assert(res != NULL);
-            assert(_PyType_HasFeature(Py_TYPE(res), Py_TPFLAGS_METHOD_DESCRIPTOR));
-            SET_TOP(Py_NewRef(res));
-            PUSH(self);
-            JUMPBY(INLINE_CACHE_ENTRIES_LOAD_ATTR);
+            assert(descr != NULL);
+            assert(_PyType_HasFeature(Py_TYPE(descr), Py_TPFLAGS_METHOD_DESCRIPTOR));
+            res2 = Py_NewRef(descr);
+            res = self;
+            assert(oparg & 1);
         }
 
         // error: LOAD_ATTR has irregular stack effect

Python/generated_cases.c.h

@@ -281,7 +281,7 @@ _PyOpcode_num_popped(int opcode, int oparg) {
         case LOAD_ATTR_METHOD_WITH_VALUES:
             return 1;
         case LOAD_ATTR_METHOD_NO_DICT:
-            return -1;
+            return 1;
         case LOAD_ATTR_METHOD_LAZY_DICT:
             return -1;
         case CALL_BOUND_METHOD_EXACT_ARGS:
@@ -627,7 +627,7 @@ _PyOpcode_num_pushed(int opcode, int oparg) {
         case LOAD_ATTR_METHOD_WITH_VALUES:
             return ((oparg & 1) ? 1 : 0) + 1;
         case LOAD_ATTR_METHOD_NO_DICT:
-            return -1;
+            return ((oparg & 1) ? 1 : 0) + 1;
         case LOAD_ATTR_METHOD_LAZY_DICT:
             return -1;
         case CALL_BOUND_METHOD_EXACT_ARGS:
@@ -839,7 +839,7 @@ struct opcode_metadata {
     [WITH_EXCEPT_START] = { DIR_NONE, DIR_NONE, DIR_NONE, true, INSTR_FMT_IX },
     [PUSH_EXC_INFO] = { DIR_NONE, DIR_NONE, DIR_NONE, true, INSTR_FMT_IX },
     [LOAD_ATTR_METHOD_WITH_VALUES] = { DIR_NONE, DIR_NONE, DIR_NONE, true, INSTR_FMT_IBC00000000 },
-    [LOAD_ATTR_METHOD_NO_DICT] = { DIR_NONE, DIR_NONE, DIR_NONE, true, INSTR_FMT_IX },
+    [LOAD_ATTR_METHOD_NO_DICT] = { DIR_NONE, DIR_NONE, DIR_NONE, true, INSTR_FMT_IBC00000000 },
     [LOAD_ATTR_METHOD_LAZY_DICT] = { DIR_NONE, DIR_NONE, DIR_NONE, true, INSTR_FMT_IX },
     [CALL_BOUND_METHOD_EXACT_ARGS] = { DIR_NONE, DIR_NONE, DIR_NONE, true, INSTR_FMT_IB },
     [KW_NAMES] = { DIR_NONE, DIR_NONE, DIR_NONE, true, INSTR_FMT_IB },