Fix our implementation of Py_Is

(cherry picked from commit 37cb91a)

Author: timfel

graalpython/com.oracle.graal.python.cext/include/object.h

@@ -1,4 +1,4 @@
-/* Copyright (c) 2018, 2024, Oracle and/or its affiliates.
+/* Copyright (c) 2018, 2025, Oracle and/or its affiliates.
  * Copyright (C) 1996-2020 Python Software Foundation
  *
  * Licensed under the PYTHON SOFTWARE FOUNDATION LICENSE VERSION 2
@@ -124,7 +124,9 @@ typedef struct {
 
 // Test if the 'x' object is the 'y' object, the same as "x is y" in Python.
 PyAPI_FUNC(int) Py_Is(PyObject *x, PyObject *y);
+#if 0 // GraalPy change
 #define Py_Is(x, y) ((x) == (y))
+#endif // GraalPy change
 
 
 PyAPI_FUNC(Py_ssize_t) PyTruffle_REFCNT(PyObject *ob);

graalpython/com.oracle.graal.python.cext/src/object.c

@@ -2507,7 +2507,12 @@ Py_XNewRef(PyObject *obj)
 // for the stable ABI.
 int Py_Is(PyObject *x, PyObject *y)
 {
+#if 0 // GraalPy change
     return (x == y);
+#else
+    return (x == y) ||
+        (points_to_py_handle_space(x) && points_to_py_handle_space(y) && GraalPyTruffle_Is(x, y));
+#endif
 }
 
 int Py_IsNone(PyObject *x)

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/modules/cext/PythonCextObjectBuiltins.java

@@ -129,6 +129,7 @@
 import com.oracle.graal.python.nodes.classes.IsSubtypeNode;
 import com.oracle.graal.python.nodes.object.GetClassNode;
 import com.oracle.graal.python.nodes.object.GetOrCreateDictNode;
+import com.oracle.graal.python.nodes.object.IsNode;
 import com.oracle.graal.python.nodes.util.CannotCastException;
 import com.oracle.graal.python.nodes.util.CastToJavaStringNode;
 import com.oracle.graal.python.nodes.util.CastToTruffleStringNode;
@@ -739,4 +740,13 @@ static Object getDict(Object object,
             return getDict.execute(inliningTarget, object);
         }
     }
+
+    @CApiBuiltin(ret = Int, args = {PyObject, PyObject}, call = Ignored)
+    abstract static class PyTruffle_Is extends CApiBinaryBuiltinNode {
+        @Specialization
+        static int isTrue(Object a, Object b,
+                        @Cached IsNode isNode) {
+            return isNode.execute(a, b) ? 1 : 0;
+        }
+    }
 }