Replace tuple deallocation with tuple free

Author: reidenong

Include/internal/pycore_tuple.h

@@ -21,7 +21,7 @@ extern PyStatus _PyTuple_InitGlobalObjects(PyInterpreterState *);
 
 /* other API */
 
-PyAPI_FUNC(void) _PyTuple_EmptyExactDealloc(PyObject *self);
+PyAPI_FUNC(void) _PyTuple_Free(PyObject *self);
 
 #define _PyTuple_ITEMS(op) _Py_RVALUE(_PyTuple_CAST(op)->ob_item)
 

Include/internal/pycore_uop_metadata.h

@@ -206,27 +206,11 @@ PyTuple_Pack(Py_ssize_t n, ...)
 /* Methods */
 
 void
-_PyTuple_EmptyExactDealloc(PyObject *obj)
+_PyTuple_Free(PyObject *obj)
 {
     assert(PyTuple_CheckExact(obj));
     PyTupleObject *op = _PyTuple_CAST(obj);
-
-    if (Py_SIZE(op) == 0 && op == &_Py_SINGLETON(tuple_empty)) {
-#ifdef Py_DEBUG
-        _Py_FatalRefcountError("deallocating the empty tuple singleton");
-#else
-        return;
-#endif
-    }
-
-    PyObject_GC_UnTrack(op);
-
-#ifdef Py_DEBUG
-    Py_ssize_t i = Py_SIZE(op);
-    while (--i >= 0) {
-        assert(op->ob_item[i] == NULL);
-    }
-#endif
+    assert(Py_SIZE(op) != 0);
 
     // This will abort on the empty singleton (if there is one).
     if (!maybe_freelist_push(op)) {

Objects/tupleobject.c

@@ -30,7 +30,7 @@
 #include "pycore_sliceobject.h"   // _PyBuildSlice_ConsumeRefs
 #include "pycore_stackref.h"
 #include "pycore_template.h"      // _PyTemplate_Build()
-#include "pycore_tuple.h"         // _PyTuple_EmptyExactDealloc(), _PyTuple_ITEMS()
+#include "pycore_tuple.h"         // _PyTuple_Free(), _PyTuple_ITEMS()
 #include "pycore_typeobject.h"    // _PySuper_Lookup()
 
 #include "pycore_dict.h"
@@ -1672,17 +1672,17 @@ dummy_func(
         }
 
         op(_UNPACK_SEQUENCE_UNIQUE_TUPLE, (seq -- values[oparg])) {
-            PyObject *seq_o = PyStackRef_AsPyObjectBorrow(seq);
+            PyObject *seq_o = PyStackRef_AsPyObjectSteal(seq);
             assert(PyTuple_CheckExact(seq_o));
             assert(PyTuple_GET_SIZE(seq_o) == oparg);
             DEOPT_IF(!_PyObject_IsUniquelyReferenced(seq_o));
             STAT_INC(UNPACK_SEQUENCE, hit);
             PyObject **items = _PyTuple_ITEMS(seq_o);
             for (int i = oparg; --i >= 0; ) {
                 *values++ = PyStackRef_FromPyObjectSteal(items[i]);
-                items[i] = NULL;
             }
-            PyStackRef_CLOSE_SPECIALIZED(seq, _PyTuple_EmptyExactDealloc);
+            PyObject_GC_UnTrack(seq_o);
+            _PyTuple_Free(seq_o);
         }
 
         macro(UNPACK_SEQUENCE_LIST) =