bpo-46008: Make runtime-global object/type lifecycle functions and state consistent. (gh-29998)

This change is strictly renames and moving code around.  It helps in the following ways:

* ensures type-related init functions focus strictly on one of the three aspects (state, objects, types)
* passes in PyInterpreterState * to all those functions, simplifying work on moving types/objects/state to the interpreter
* consistent naming conventions help make what's going on more clear
* keeping API related to a type in the corresponding header file makes it more obvious where to look for it

https://bugs.python.org/issue46008

Include/internal/pycore_tuple.h

@@ -10,6 +10,43 @@ extern "C" {
 
 #include "tupleobject.h"   /* _PyTuple_CAST() */
 
+
+/* runtime lifecycle */
+
+extern PyStatus _PyTuple_InitGlobalObjects(PyInterpreterState *);
+extern PyStatus _PyTuple_InitTypes(PyInterpreterState *);
+extern void _PyTuple_Fini(PyInterpreterState *);
+
+
+/* other API */
+
+#ifndef WITH_FREELISTS
+// without freelists
+// for tuples only store empty tuple singleton
+#  define PyTuple_MAXSAVESIZE 1
+#  define PyTuple_MAXFREELIST 1
+#endif
+
+/* Speed optimization to avoid frequent malloc/free of small tuples */
+#ifndef PyTuple_MAXSAVESIZE
+   // Largest tuple to save on free list
+#  define PyTuple_MAXSAVESIZE 20
+#endif
+#ifndef PyTuple_MAXFREELIST
+   // Maximum number of tuples of each size to save
+#  define PyTuple_MAXFREELIST 2000
+#endif
+
+struct _Py_tuple_state {
+#if PyTuple_MAXSAVESIZE > 0
+    /* Entries 1 up to PyTuple_MAXSAVESIZE are free lists,
+       entry 0 is the empty tuple () of which at most one instance
+       will be allocated. */
+    PyTupleObject *free_list[PyTuple_MAXSAVESIZE];
+    int numfree[PyTuple_MAXSAVESIZE];
+#endif
+};
+
 #define _PyTuple_ITEMS(op) (_PyTuple_CAST(op)->ob_item)
 
 extern PyObject *_PyTuple_FromArray(PyObject *const *, Py_ssize_t);