gh-99300: Use Py_NewRef() in Python/ directory (#99317)

Replace Py_INCREF() and Py_XINCREF() with Py_NewRef() and
Py_XNewRef() in C files of the Python/ directory.

Update Parser/asdl_c.py to regenerate Python/Python-ast.c.

Author: vstinner

Parser/asdl_c.py

@@ -995,10 +995,11 @@ def visitModule(self, mod):
 
 static PyObject* ast2obj_object(struct ast_state *Py_UNUSED(state), void *o)
 {
-    if (!o)
-        o = Py_None;
-    Py_INCREF((PyObject*)o);
-    return (PyObject*)o;
+    PyObject *op = (PyObject*)o;
+    if (!op) {
+        op = Py_None;
+    }
+    return Py_NewRef(op);
 }
 #define ast2obj_constant ast2obj_object
 #define ast2obj_identifier ast2obj_object
@@ -1032,8 +1033,7 @@ def visitModule(self, mod):
         *out = NULL;
         return -1;
     }
-    Py_INCREF(obj);
-    *out = obj;
+    *out = Py_NewRef(obj);
     return 0;
 }
 
@@ -1301,8 +1301,7 @@ def simpleSum(self, sum, name):
         self.emit("switch(o) {", 1)
         for t in sum.types:
             self.emit("case %s:" % t.name, 2)
-            self.emit("Py_INCREF(state->%s_singleton);" % t.name, 3)
-            self.emit("return state->%s_singleton;" % t.name, 3)
+            self.emit("return Py_NewRef(state->%s_singleton);" % t.name, 3)
         self.emit("}", 1)
         self.emit("Py_UNREACHABLE();", 1);
         self.emit("}", 0)

Python/Python-ast.c

@@ -63,8 +63,7 @@ update_bases(PyObject *bases, PyObject *const *args, Py_ssize_t nargs)
             }
             for (j = 0; j < i; j++) {
                 base = args[j];
-                PyList_SET_ITEM(new_bases, j, base);
-                Py_INCREF(base);
+                PyList_SET_ITEM(new_bases, j, Py_NewRef(base));
             }
         }
         j = PyList_GET_SIZE(new_bases);
@@ -170,8 +169,7 @@ builtin___build_class__(PyObject *self, PyObject *const *args, Py_ssize_t nargs,
         }
         if (winner != meta) {
             Py_DECREF(meta);
-            meta = winner;
-            Py_INCREF(meta);
+            meta = Py_NewRef(winner);
         }
     }
     /* else: meta is not a class, so we cannot do the metaclass
@@ -804,8 +802,7 @@ builtin_compile_impl(PyObject *module, PyObject *source, PyObject *filename,
         goto error;
     if (is_ast) {
         if (flags & PyCF_ONLY_AST) {
-            Py_INCREF(source);
-            result = source;
+            result = Py_NewRef(source);
         }
         else {
             PyArena *arena;
@@ -1128,8 +1125,7 @@ builtin_getattr(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
     if (nargs > 2) {
         if (_PyObject_LookupAttr(v, name, &result) == 0) {
             PyObject *dflt = args[2];
-            Py_INCREF(dflt);
-            return dflt;
+            return Py_NewRef(dflt);
         }
     }
     else {
@@ -1162,8 +1158,7 @@ builtin_globals_impl(PyObject *module)
     PyObject *d;
 
     d = PyEval_GetGlobals();
-    Py_XINCREF(d);
-    return d;
+    return Py_XNewRef(d);
 }
 
 
@@ -1390,12 +1385,10 @@ map_reduce(mapobject *lz, PyObject *Py_UNUSED(ignored))
     Py_ssize_t i;
     if (args == NULL)
         return NULL;
-    Py_INCREF(lz->func);
-    PyTuple_SET_ITEM(args, 0, lz->func);
+    PyTuple_SET_ITEM(args, 0, Py_NewRef(lz->func));
     for (i = 0; i<numargs; i++){
         PyObject *it = PyTuple_GET_ITEM(lz->iters, i);
-        Py_INCREF(it);
-        PyTuple_SET_ITEM(args, i+1, it);
+        PyTuple_SET_ITEM(args, i+1, Py_NewRef(it));
     }
 
     return Py_BuildValue("ON", Py_TYPE(lz), args);
@@ -1486,8 +1479,7 @@ builtin_next(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
                 return NULL;
             PyErr_Clear();
         }
-        Py_INCREF(def);
-        return def;
+        return Py_NewRef(def);
     } else if (PyErr_Occurred()) {
         return NULL;
     } else {
@@ -1723,8 +1715,7 @@ builtin_locals_impl(PyObject *module)
     PyObject *d;
 
     d = PyEval_GetLocals();
-    Py_XINCREF(d);
-    return d;
+    return Py_XNewRef(d);
 }
 
 
@@ -1785,8 +1776,7 @@ min_max(PyObject *args, PyObject *kwds, int op)
         }
         /* no key function; the value is the item */
         else {
-            val = item;
-            Py_INCREF(val);
+            val = Py_NewRef(item);
         }
 
         /* maximum value and item are unset; set them */
@@ -1816,8 +1806,7 @@ min_max(PyObject *args, PyObject *kwds, int op)
     if (maxval == NULL) {
         assert(maxitem == NULL);
         if (defaultval != NULL) {
-            Py_INCREF(defaultval);
-            maxitem = defaultval;
+            maxitem = Py_NewRef(defaultval);
         } else {
             PyErr_Format(PyExc_ValueError,
                          "%s() arg is an empty sequence", name);
@@ -2737,8 +2726,7 @@ zip_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
         return NULL;
     }
     for (i=0 ; i < tuplesize ; i++) {
-        Py_INCREF(Py_None);
-        PyTuple_SET_ITEM(result, i, Py_None);
+        PyTuple_SET_ITEM(result, i, Py_NewRef(Py_None));
     }
 
     /* create zipobject structure */