[3.13] gh-120838: Add _PyThreadState_WHENCE_FINI (gh-121013)

We also add _PyThreadState_NewBound() and drop _PyThreadState_SetWhence().

This change only affects internal API.

(cherry picked from commit a905721b9c5c15279e67c2f7785034b7356b2d46, AKA gh-121010)

Co-authored-by: Eric Snow <ericsnowcurrently@gmail.com>

4 files changed, 15 insertions, 13 deletions

diff --git a/Python/crossinterp.c b/Python/crossinterp.c
index 367e29d..a03456a 100644
--- a/Python/crossinterp.c
+++ b/Python/crossinterp.c
@@ -1544,8 +1544,7 @@ _enter_session(_PyXI_session *session, PyInterpreterState *interp)
     PyThreadState *tstate = PyThreadState_Get();
     PyThreadState *prev = tstate;
     if (interp != tstate->interp) {
-        tstate = PyThreadState_New(interp);
-        _PyThreadState_SetWhence(tstate, _PyThreadState_WHENCE_EXEC);
+        tstate = _PyThreadState_NewBound(interp, _PyThreadState_WHENCE_EXEC);
         // XXX Possible GILState issues?
         session->prev_tstate = PyThreadState_Swap(tstate);
         assert(session->prev_tstate == prev);
@@ -1895,8 +1894,7 @@ _PyXI_EndInterpreter(PyInterpreterState *interp,
             tstate = cur_tstate;
         }
         else {
-            tstate = PyThreadState_New(interp);
-            _PyThreadState_SetWhence(tstate, _PyThreadState_WHENCE_INTERP);
+            tstate = _PyThreadState_NewBound(interp, _PyThreadState_WHENCE_FINI);
             assert(tstate != NULL);
             save_tstate = PyThreadState_Swap(tstate);
         }
diff --git a/Python/import.c b/Python/import.c
index dc7ff90..98ecaed 100644
--- a/Python/import.c
+++ b/Python/import.c
@@ -1518,11 +1518,11 @@ switch_to_main_interpreter(PyThreadState *tstate)
     if (_Py_IsMainInterpreter(tstate->interp)) {
         return tstate;
     }
-    PyThreadState *main_tstate = PyThreadState_New(_PyInterpreterState_Main());
+    PyThreadState *main_tstate = _PyThreadState_NewBound(
+            _PyInterpreterState_Main(), _PyThreadState_WHENCE_EXEC);
     if (main_tstate == NULL) {
         return NULL;
     }
-    main_tstate->_whence = _PyThreadState_WHENCE_EXEC;
 #ifndef NDEBUG
     PyThreadState *old_tstate = PyThreadState_Swap(main_tstate);
     assert(old_tstate == tstate);
diff --git a/Python/pylifecycle.c b/Python/pylifecycle.c
index e5f749b..3580ca4 100644
--- a/Python/pylifecycle.c
+++ b/Python/pylifecycle.c
@@ -677,7 +677,7 @@ pycore_create_interpreter(_PyRuntimeState *runtime,
     }
 
     PyThreadState *tstate = _PyThreadState_New(interp,
-                                               _PyThreadState_WHENCE_INTERP);
+                                               _PyThreadState_WHENCE_INIT);
     if (tstate == NULL) {
         return _PyStatus_ERR("can't make first thread");
     }
@@ -2233,7 +2233,7 @@ new_interpreter(PyThreadState **tstate_p,
         goto error;
     }
 
-    tstate = _PyThreadState_New(interp, _PyThreadState_WHENCE_INTERP);
+    tstate = _PyThreadState_New(interp, _PyThreadState_WHENCE_INIT);
     if (tstate == NULL) {
         status = _PyStatus_NO_MEMORY();
         goto error;
diff --git a/Python/pystate.c b/Python/pystate.c
index 8d31a4d..602b13e 100644
--- a/Python/pystate.c
+++ b/Python/pystate.c
@@ -1293,9 +1293,8 @@ _PyInterpreterState_IDDecref(PyInterpreterState *interp)
     PyThread_release_lock(interp->id_mutex);
 
     if (refcount == 0 && interp->requires_idref) {
-        PyThreadState *tstate = _PyThreadState_New(interp,
-                                                   _PyThreadState_WHENCE_INTERP);
-        _PyThreadState_Bind(tstate);
+        PyThreadState *tstate =
+            _PyThreadState_NewBound(interp, _PyThreadState_WHENCE_FINI);
 
         // XXX Possible GILState issues?
         PyThreadState *save_tstate = _PyThreadState_Swap(runtime, tstate);
@@ -1603,8 +1602,13 @@ new_threadstate(PyInterpreterState *interp, int whence)
 PyThreadState *
 PyThreadState_New(PyInterpreterState *interp)
 {
-    PyThreadState *tstate = new_threadstate(interp,
-                                            _PyThreadState_WHENCE_UNKNOWN);
+    return _PyThreadState_NewBound(interp, _PyThreadState_WHENCE_UNKNOWN);
+}
+
+PyThreadState *
+_PyThreadState_NewBound(PyInterpreterState *interp, int whence)
+{
+    PyThreadState *tstate = new_threadstate(interp, whence);
     if (tstate) {
         bind_tstate(tstate);
         // This makes sure there's a gilstate tstate bound