_long_is_small_int() -> _PyLong_IsImmortal() helper

Author: skirpichev

Include/internal/pycore_long.h

@@ -231,6 +231,15 @@ _PyLong_IsPositive(const PyLongObject *op)
     return (op->long_value.lv_tag & SIGN_MASK) == 0;
 }
 
+static inline bool
+_PyLong_IsImmortal(const PyLongObject *op)
+{
+    assert(PyLong_Check(op));
+    bool is_small_int = (op->long_value.lv_tag & IMMORTALITY_BIT_MASK) != 0;
+    assert(PyLong_CheckExact(op) || (!is_small_int));
+    return is_small_int;
+}
+
 static inline Py_ssize_t
 _PyLong_DigitCount(const PyLongObject *op)
 {
@@ -292,7 +301,9 @@ _PyLong_SetDigitCount(PyLongObject *op, Py_ssize_t size)
 #define NON_SIZE_MASK ~(uintptr_t)((1 << NON_SIZE_BITS) - 1)
 
 static inline void
-_PyLong_FlipSign(PyLongObject *op) {
+_PyLong_FlipSign(PyLongObject *op)
+{
+    assert(!_PyLong_IsImmortal(op));
     unsigned int flipped_sign = 2 - (op->long_value.lv_tag & SIGN_MASK);
     op->long_value.lv_tag &= NON_SIZE_MASK;
     op->long_value.lv_tag |= flipped_sign;

Modules/_testcapi/immortal.c

@@ -31,13 +31,13 @@ test_immortal_small_ints(PyObject *self, PyObject *Py_UNUSED(ignored))
     for (int i = -5; i <= 1024; i++) {
         PyObject *obj = PyLong_FromLong(i);
         assert(verify_immortality(obj));
-        int has_int_immortal_bit = ((PyLongObject *)obj)->long_value.lv_tag & IMMORTALITY_BIT_MASK;
+        int has_int_immortal_bit = _PyLong_IsImmortal((PyLongObject *)obj);
         assert(has_int_immortal_bit);
     }
     for (int i = 1025; i <= 1030; i++) {
         PyObject *obj = PyLong_FromLong(i);
         assert(obj);
-        int has_int_immortal_bit = ((PyLongObject *)obj)->long_value.lv_tag & IMMORTALITY_BIT_MASK;
+        int has_int_immortal_bit = _PyLong_IsImmortal((PyLongObject *)obj);
         assert(!has_int_immortal_bit);
         Py_DECREF(obj);
     }

Objects/longobject.c

@@ -3622,21 +3622,11 @@ long_richcompare(PyObject *self, PyObject *other, int op)
     Py_RETURN_RICHCOMPARE(result, 0, op);
 }
 
-static inline int
-/// Return 1 if the object is one of the immortal small ints
-_long_is_small_int(PyObject *op)
-{
-    PyLongObject *long_object = (PyLongObject *)op;
-    int is_small_int = (long_object->long_value.lv_tag & IMMORTALITY_BIT_MASK) != 0;
-    assert((!is_small_int) || PyLong_CheckExact(op));
-    return is_small_int;
-}
-
 void
 _PyLong_ExactDealloc(PyObject *self)
 {
     assert(PyLong_CheckExact(self));
-    if (_long_is_small_int(self)) {
+    if (_PyLong_IsImmortal((PyLongObject *)self)) {
         // See PEP 683, section Accidental De-Immortalizing for details
         _Py_SetImmortal(self);
         return;
@@ -3651,7 +3641,7 @@ _PyLong_ExactDealloc(PyObject *self)
 static void
 long_dealloc(PyObject *self)
 {
-    if (_long_is_small_int(self)) {
+    if (_PyLong_IsImmortal((PyLongObject *)self)) {
         /* This should never get called, but we also don't want to SEGV if
          * we accidentally decref small Ints out of existence. Instead,
          * since small Ints are immortal, re-set the reference count.