gh-76785: Crossinterp utils additions (gh-111530)

This moves several general internal APIs out of _xxsubinterpretersmodule.c and into the new Python/crossinterp.c (and the corresponding internal headers).

Specifically:

* _Py_excinfo, etc.:  the initial implementation for non-object exception snapshots (in pycore_pyerrors.h and Python/errors.c)
* _PyXI_exception_info, etc.:  helpers for passing an exception beween interpreters (wraps _Py_excinfo)
* _PyXI_namespace, etc.:  helpers for copying a dict of attrs between interpreters
* _PyXI_Enter(), _PyXI_Exit():  functions that abstract out the transitions between one interpreter and a second that will do some work temporarily

Again, these were all abstracted out of _xxsubinterpretersmodule.c as generalizations.  I plan on proposing these as public API at some point.

1 files changed, 1 insertions, 18 deletions

diff --git a/Python/pystate.c b/Python/pystate.c
index d97a03c..8970e17 100644
--- a/Python/pystate.c
+++ b/Python/pystate.c
@@ -382,7 +382,7 @@ _Py_COMP_DIAG_POP
 #define LOCKS_INIT(runtime) \
     { \
         &(runtime)->interpreters.mutex, \
-        &(runtime)->xidregistry.mutex, \
+        &(runtime)->xi.registry.mutex, \
         &(runtime)->getargs.mutex, \
         &(runtime)->unicode_state.ids.lock, \
         &(runtime)->imports.extensions.mutex, \
@@ -494,9 +494,6 @@ _PyRuntimeState_Init(_PyRuntimeState *runtime)
     return _PyStatus_OK();
 }
 
-// This is defined in crossinterp.c (for now).
-extern void _Py_xidregistry_clear(struct _xidregistry *);
-
 void
 _PyRuntimeState_Fini(_PyRuntimeState *runtime)
 {
@@ -505,8 +502,6 @@ _PyRuntimeState_Fini(_PyRuntimeState *runtime)
     assert(runtime->object_state.interpreter_leaks == 0);
 #endif
 
-    _Py_xidregistry_clear(&runtime->xidregistry);
-
     if (gilstate_tss_initialized(runtime)) {
         gilstate_tss_fini(runtime);
     }
@@ -552,11 +547,6 @@ _PyRuntimeState_ReInitThreads(_PyRuntimeState *runtime)
     for (int i = 0; i < NUMLOCKS; i++) {
         reinit_err += _PyThread_at_fork_reinit(lockptrs[i]);
     }
-    /* PyOS_AfterFork_Child(), which calls this function, later calls
-       _PyInterpreterState_DeleteExceptMain(), so we only need to update
-       the main interpreter here. */
-    assert(runtime->interpreters.main != NULL);
-    runtime->interpreters.main->xidregistry.mutex = runtime->xidregistry.mutex;
 
     PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
 
@@ -720,9 +710,6 @@ init_interpreter(PyInterpreterState *interp,
     }
     interp->f_opcode_trace_set = false;
 
-    assert(runtime->xidregistry.mutex != NULL);
-    interp->xidregistry.mutex = runtime->xidregistry.mutex;
-
     interp->_initialized = 1;
     return _PyStatus_OK();
 }
@@ -948,10 +935,6 @@ interpreter_clear(PyInterpreterState *interp, PyThreadState *tstate)
     Py_CLEAR(interp->sysdict);
     Py_CLEAR(interp->builtins);
 
-    _Py_xidregistry_clear(&interp->xidregistry);
-    /* The lock is owned by the runtime, so we don't free it here. */
-    interp->xidregistry.mutex = NULL;
-
     if (tstate->interp == interp) {
         /* We are now safe to fix tstate->_status.cleared. */
         // XXX Do this (much) earlier?