gh-128137: Update PyASCIIObject to handle interned field with the atomic operation

Include/cpython/unicodeobject.h

@@ -109,7 +109,7 @@ typedef struct {
                3: Interned, Immortal, and Static
            This categorization allows the runtime to determine the right
            cleanup mechanism at runtime shutdown. */
-        unsigned int interned:2;
+        uint8_t interned;
         /* Character size:
 
            - PyUnicode_1BYTE_KIND (1):
@@ -146,7 +146,7 @@ typedef struct {
         unsigned int statically_allocated:1;
         /* Padding to ensure that PyUnicode_DATA() is always aligned to
            4 bytes (see issue #19537 on m68k). */
-        unsigned int :24;
+        unsigned int :18;
     } state;
 } PyASCIIObject;
 
@@ -195,7 +195,11 @@ typedef struct {
 
 /* Use only if you know it's a string */
 static inline unsigned int PyUnicode_CHECK_INTERNED(PyObject *op) {
+#ifdef Py_GIL_DISABLED
+    return _Py_atomic_load_uint8_relaxed(&_PyASCIIObject_CAST(op)->state.interned);
+#else
     return _PyASCIIObject_CAST(op)->state.interned;
+#endif
 }
 #define PyUnicode_CHECK_INTERNED(op) PyUnicode_CHECK_INTERNED(_PyObject_CAST(op))
 

Misc/NEWS.d/next/Core_and_Builtins/2024-12-24-01-40-12.gh-issue-128137.gsTwr_.rst

@@ -0,0 +1,2 @@
+Update :c:type:`PyASCIIObject` layout to handle interned field with the
+atomic operation. Patch by Donghee Na.

Objects/unicodeobject.c

@@ -15726,7 +15726,7 @@ immortalize_interned(PyObject *s)
         _Py_DecRefTotal(_PyThreadState_GET());
     }
 #endif
-    _PyUnicode_STATE(s).interned = SSTATE_INTERNED_IMMORTAL;
+    FT_ATOMIC_STORE_UINT8_RELAXED(_PyUnicode_STATE(s).interned, SSTATE_INTERNED_IMMORTAL);
     _Py_SetImmortal(s);
 }
 
@@ -15845,7 +15845,7 @@ intern_common(PyInterpreterState *interp, PyObject *s /* stolen */,
         _Py_DecRefTotal(_PyThreadState_GET());
 #endif
     }
-    _PyUnicode_STATE(s).interned = SSTATE_INTERNED_MORTAL;
+    FT_ATOMIC_STORE_UINT8_RELAXED(_PyUnicode_STATE(s).interned, SSTATE_INTERNED_MORTAL);
 
     /* INTERNED_MORTAL -> INTERNED_IMMORTAL (if needed) */
 
@@ -15981,7 +15981,7 @@ _PyUnicode_ClearInterned(PyInterpreterState *interp)
             Py_UNREACHABLE();
         }
         if (!shared) {
-            _PyUnicode_STATE(s).interned = SSTATE_NOT_INTERNED;
+            FT_ATOMIC_STORE_UINT8_RELAXED(_PyUnicode_STATE(s).interned, SSTATE_NOT_INTERNED);
         }
     }
 #ifdef INTERNED_STATS