bpo-39245: Switch to public API for Vectorcall (GH-18460)

The bulk of this patch was generated automatically with:

    for name in \
        PyObject_Vectorcall \
        Py_TPFLAGS_HAVE_VECTORCALL \
        PyObject_VectorcallMethod \
        PyVectorcall_Function \
        PyObject_CallOneArg \
        PyObject_CallMethodNoArgs \
        PyObject_CallMethodOneArg \
    ;
    do
        echo $name
        git grep -lwz _$name | xargs -0 sed -i "s/\b_$name\b/$name/g"
    done

    old=_PyObject_FastCallDict
    new=PyObject_VectorcallDict
    git grep -lwz $old | xargs -0 sed -i "s/\b$old\b/$new/g"

and then cleaned up:

- Revert changes to in docs & news
- Revert changes to backcompat defines in headers
- Nudge misaligned comments

1 files changed, 4 insertions, 4 deletions

diff --git a/Objects/genobject.c b/Objects/genobject.c
index 652c2903dd2..576d6856c7f 100644
--- a/Objects/genobject.c
+++ b/Objects/genobject.c
@@ -58,7 +58,7 @@ _PyGen_Finalize(PyObject *self)
             /* Save the current exception, if any. */
             PyErr_Fetch(&error_type, &error_value, &error_traceback);
 
-            res = _PyObject_CallOneArg(finalizer, self);
+            res = PyObject_CallOneArg(finalizer, self);
 
             if (res == NULL) {
                 PyErr_WriteUnraisable(self);
@@ -563,7 +563,7 @@ _PyGen_SetStopIterationValue(PyObject *value)
         return 0;
     }
     /* Construct an exception instance manually with
-     * _PyObject_CallOneArg and pass it to PyErr_SetObject.
+     * PyObject_CallOneArg and pass it to PyErr_SetObject.
      *
      * We do this to handle a situation when "value" is a tuple, in which
      * case PyErr_SetObject would set the value of StopIteration to
@@ -571,7 +571,7 @@ _PyGen_SetStopIterationValue(PyObject *value)
      *
      * (See PyErr_SetObject/_PyErr_CreateException code for details.)
      */
-    e = _PyObject_CallOneArg(PyExc_StopIteration, value);
+    e = PyObject_CallOneArg(PyExc_StopIteration, value);
     if (e == NULL) {
         return -1;
     }
@@ -1264,7 +1264,7 @@ async_gen_init_hooks(PyAsyncGenObject *o)
         PyObject *res;
 
         Py_INCREF(firstiter);
-        res = _PyObject_CallOneArg(firstiter, (PyObject *)o);
+        res = PyObject_CallOneArg(firstiter, (PyObject *)o);
         Py_DECREF(firstiter);
         if (res == NULL) {
             return 1;