gh-127022: Simplify `PyStackRef_FromPyObjectSteal` (#127024)

This gets rid of the immortal check in `PyStackRef_FromPyObjectSteal()`.
Overall, this improves performance about 2% in the free threading
build.

This also renames `PyStackRef_Is()` to `PyStackRef_IsExactly()` because
the macro requires that the tag bits of the arguments match, which is
only true in certain special cases.

5 files changed, 57 insertions, 72 deletions

diff --git a/Include/internal/pycore_stackref.h b/Include/internal/pycore_stackref.h
index 588e57f..90a3118 100644
--- a/Include/internal/pycore_stackref.h
+++ b/Include/internal/pycore_stackref.h
@@ -99,8 +99,7 @@ _PyStackRef_FromPyObjectSteal(PyObject *obj)
     assert(obj != NULL);
     // Make sure we don't take an already tagged value.
     assert(((uintptr_t)obj & Py_TAG_BITS) == 0);
-    unsigned int tag = _Py_IsImmortal(obj) ? (Py_TAG_DEFERRED) : Py_TAG_PTR;
-    return ((_PyStackRef){.bits = ((uintptr_t)(obj)) | tag});
+    return (_PyStackRef){ .bits = (uintptr_t)obj };
 }
 #   define PyStackRef_FromPyObjectSteal(obj) _PyStackRef_FromPyObjectSteal(_PyObject_CAST(obj))
 
@@ -190,9 +189,16 @@ static const _PyStackRef PyStackRef_NULL = { .bits = 0 };
 
 #endif // Py_GIL_DISABLED
 
-// Note: this is a macro because MSVC (Windows) has trouble inlining it.
+// Check if a stackref is exactly the same as another stackref, including the
+// the deferred bit. This can only be used safely if you know that the deferred
+// bits of `a` and `b` match.
+#define PyStackRef_IsExactly(a, b) \
+    (assert(((a).bits & Py_TAG_BITS) == ((b).bits & Py_TAG_BITS)), (a).bits == (b).bits)
 
-#define PyStackRef_Is(a, b) ((a).bits == (b).bits)
+// Checks that mask out the deferred bit in the free threading build.
+#define PyStackRef_IsNone(ref) (PyStackRef_AsPyObjectBorrow(ref) == Py_None)
+#define PyStackRef_IsTrue(ref) (PyStackRef_AsPyObjectBorrow(ref) == Py_True)
+#define PyStackRef_IsFalse(ref) (PyStackRef_AsPyObjectBorrow(ref) == Py_False)
 
 // Converts a PyStackRef back to a PyObject *, converting the
 // stackref to a new reference.
diff --git a/Python/bytecodes.c b/Python/bytecodes.c
index 83240d5..88e96af 100644
--- a/Python/bytecodes.c
+++ b/Python/bytecodes.c
@@ -376,7 +376,7 @@ dummy_func(
 
         pure inst(UNARY_NOT, (value -- res)) {
             assert(PyStackRef_BoolCheck(value));
-            res = PyStackRef_Is(value, PyStackRef_False)
+            res = PyStackRef_IsFalse(value)
                 ? PyStackRef_True : PyStackRef_False;
             DEAD(value);
         }
@@ -441,7 +441,7 @@ dummy_func(
 
         inst(TO_BOOL_NONE, (unused/1, unused/2, value -- res)) {
             // This one is a bit weird, because we expect *some* failures:
-            EXIT_IF(!PyStackRef_Is(value, PyStackRef_None));
+            EXIT_IF(!PyStackRef_IsNone(value));
             DEAD(value);
             STAT_INC(TO_BOOL, hit);
             res = PyStackRef_False;
@@ -651,9 +651,7 @@ dummy_func(
         // specializations, but there is no output.
         // At the end we just skip over the STORE_FAST.
         op(_BINARY_OP_INPLACE_ADD_UNICODE, (left, right --)) {
-        #ifndef NDEBUG
             PyObject *left_o = PyStackRef_AsPyObjectBorrow(left);
-        #endif
             PyObject *right_o = PyStackRef_AsPyObjectBorrow(right);
 
             int next_oparg;
@@ -664,7 +662,7 @@ dummy_func(
             next_oparg = CURRENT_OPERAND0();
         #endif
             _PyStackRef *target_local = &GETLOCAL(next_oparg);
-            DEOPT_IF(!PyStackRef_Is(*target_local, left));
+            DEOPT_IF(PyStackRef_AsPyObjectBorrow(*target_local) != left_o);
             STAT_INC(BINARY_OP, hit);
             /* Handle `left = left + right` or `left += right` for str.
              *
@@ -1141,7 +1139,7 @@ dummy_func(
                 gen_frame->previous = frame;
                 DISPATCH_INLINED(gen_frame);
             }
-            if (PyStackRef_Is(v, PyStackRef_None) && PyIter_Check(receiver_o)) {
+            if (PyStackRef_IsNone(v) && PyIter_Check(receiver_o)) {
                 retval_o = Py_TYPE(receiver_o)->tp_iternext(receiver_o);
             }
             else {
@@ -1249,7 +1247,7 @@ dummy_func(
         inst(POP_EXCEPT, (exc_value -- )) {
             _PyErr_StackItem *exc_info = tstate->exc_info;
             Py_XSETREF(exc_info->exc_value,
-                   PyStackRef_Is(exc_value, PyStackRef_None)
+                   PyStackRef_IsNone(exc_value)
                     ? NULL : PyStackRef_AsPyObjectSteal(exc_value));
         }
 
@@ -2502,13 +2500,7 @@ dummy_func(
         }
 
         inst(IS_OP, (left, right -- b)) {
-#ifdef Py_GIL_DISABLED
-            // On free-threaded builds, objects are conditionally immortalized.
-            // So their bits don't always compare equally.
             int res = Py_Is(PyStackRef_AsPyObjectBorrow(left), PyStackRef_AsPyObjectBorrow(right)) ^ oparg;
-#else
-            int res = PyStackRef_Is(left, right) ^ oparg;
-#endif
             DECREF_INPUTS();
             b = res ? PyStackRef_True : PyStackRef_False;
         }
@@ -2715,7 +2707,7 @@ dummy_func(
 
         replaced op(_POP_JUMP_IF_FALSE, (cond -- )) {
             assert(PyStackRef_BoolCheck(cond));
-            int flag = PyStackRef_Is(cond, PyStackRef_False);
+            int flag = PyStackRef_IsFalse(cond);
             DEAD(cond);
             RECORD_BRANCH_TAKEN(this_instr[1].cache, flag);
             JUMPBY(oparg * flag);
@@ -2723,14 +2715,14 @@ dummy_func(
 
         replaced op(_POP_JUMP_IF_TRUE, (cond -- )) {
             assert(PyStackRef_BoolCheck(cond));
-            int flag = PyStackRef_Is(cond, PyStackRef_True);
+            int flag = PyStackRef_IsTrue(cond);
             DEAD(cond);
             RECORD_BRANCH_TAKEN(this_instr[1].cache, flag);
             JUMPBY(oparg * flag);
         }
 
         op(_IS_NONE, (value -- b)) {
-            if (PyStackRef_Is(value, PyStackRef_None)) {
+            if (PyStackRef_IsNone(value)) {
                 b = PyStackRef_True;
                 DEAD(value);
             }
@@ -3774,7 +3766,7 @@ dummy_func(
 
         inst(EXIT_INIT_CHECK, (should_be_none -- )) {
             assert(STACK_LEVEL() == 2);
-            if (!PyStackRef_Is(should_be_none, PyStackRef_None)) {
+            if (!PyStackRef_IsNone(should_be_none)) {
                 PyErr_Format(PyExc_TypeError,
                     "__init__() should return None, not '%.200s'",
                     Py_TYPE(PyStackRef_AsPyObjectBorrow(should_be_none))->tp_name);
@@ -4734,7 +4726,7 @@ dummy_func(
         inst(INSTRUMENTED_POP_JUMP_IF_TRUE, (unused/1 -- )) {
             _PyStackRef cond = POP();
             assert(PyStackRef_BoolCheck(cond));
-            int flag = PyStackRef_Is(cond, PyStackRef_True);
+            int flag = PyStackRef_IsTrue(cond);
             int offset = flag * oparg;
             RECORD_BRANCH_TAKEN(this_instr[1].cache, flag);
             INSTRUMENTED_JUMP(this_instr, next_instr + offset, PY_MONITORING_EVENT_BRANCH);
@@ -4743,7 +4735,7 @@ dummy_func(
         inst(INSTRUMENTED_POP_JUMP_IF_FALSE, (unused/1 -- )) {
             _PyStackRef cond = POP();
             assert(PyStackRef_BoolCheck(cond));
-            int flag = PyStackRef_Is(cond, PyStackRef_False);
+            int flag = PyStackRef_IsFalse(cond);
             int offset = flag * oparg;
             RECORD_BRANCH_TAKEN(this_instr[1].cache, flag);
             INSTRUMENTED_JUMP(this_instr, next_instr + offset, PY_MONITORING_EVENT_BRANCH);
@@ -4751,7 +4743,7 @@ dummy_func(
 
         inst(INSTRUMENTED_POP_JUMP_IF_NONE, (unused/1 -- )) {
             _PyStackRef value_stackref = POP();
-            int flag = PyStackRef_Is(value_stackref, PyStackRef_None);
+            int flag = PyStackRef_IsNone(value_stackref);
             int offset;
             if (flag) {
                 offset = oparg;
@@ -4767,7 +4759,7 @@ dummy_func(
         inst(INSTRUMENTED_POP_JUMP_IF_NOT_NONE, (unused/1 -- )) {
             _PyStackRef value_stackref = POP();
             int offset;
-            int nflag = PyStackRef_Is(value_stackref, PyStackRef_None);
+            int nflag = PyStackRef_IsNone(value_stackref);
             if (nflag) {
                 offset = 0;
             }
@@ -4802,21 +4794,21 @@ dummy_func(
         ///////// Tier-2 only opcodes /////////
 
         op (_GUARD_IS_TRUE_POP, (flag -- )) {
-            int is_true = PyStackRef_Is(flag, PyStackRef_True);
+            int is_true = PyStackRef_IsTrue(flag);
             DEAD(flag);
             SYNC_SP();
             EXIT_IF(!is_true);
         }
 
         op (_GUARD_IS_FALSE_POP, (flag -- )) {
-            int is_false = PyStackRef_Is(flag, PyStackRef_False);
+            int is_false = PyStackRef_IsFalse(flag);
             DEAD(flag);
             SYNC_SP();
             EXIT_IF(!is_false);
         }
 
         op (_GUARD_IS_NONE_POP, (val -- )) {
-            int is_none = PyStackRef_Is(val, PyStackRef_None);
+            int is_none = PyStackRef_IsNone(val);
             if (!is_none) {
                 PyStackRef_CLOSE(val);
                 SYNC_SP();
@@ -4826,7 +4818,7 @@ dummy_func(
         }
 
         op (_GUARD_IS_NOT_NONE_POP, (val -- )) {
-            int is_none = PyStackRef_Is(val, PyStackRef_None);
+            int is_none = PyStackRef_IsNone(val);
             PyStackRef_CLOSE(val);
             SYNC_SP();
             EXIT_IF(is_none);
diff --git a/Python/executor_cases.c.h b/Python/executor_cases.c.h
index 22de7ca..5af970e 100644
--- a/Python/executor_cases.c.h
+++ b/Python/executor_cases.c.h
@@ -445,7 +445,7 @@
             _PyStackRef res;
             value = stack_pointer[-1];
             assert(PyStackRef_BoolCheck(value));
-            res = PyStackRef_Is(value, PyStackRef_False)
+            res = PyStackRef_IsFalse(value)
             ? PyStackRef_True : PyStackRef_False;
             stack_pointer[-1] = res;
             break;
@@ -519,7 +519,7 @@
             _PyStackRef res;
             value = stack_pointer[-1];
             // This one is a bit weird, because we expect *some* failures:
-            if (!PyStackRef_Is(value, PyStackRef_None)) {
+            if (!PyStackRef_IsNone(value)) {
                 UOP_STAT_INC(uopcode, miss);
                 JUMP_TO_JUMP_TARGET();
             }
@@ -822,9 +822,7 @@
             _PyStackRef left;
             right = stack_pointer[-1];
             left = stack_pointer[-2];
-            #ifndef NDEBUG
             PyObject *left_o = PyStackRef_AsPyObjectBorrow(left);
-            #endif
             PyObject *right_o = PyStackRef_AsPyObjectBorrow(right);
             int next_oparg;
             #if TIER_ONE
@@ -834,7 +832,7 @@
             next_oparg = CURRENT_OPERAND0();
             #endif
             _PyStackRef *target_local = &GETLOCAL(next_oparg);
-            if (!PyStackRef_Is(*target_local, left)) {
+            if (PyStackRef_AsPyObjectBorrow(*target_local) != left_o) {
                 UOP_STAT_INC(uopcode, miss);
                 JUMP_TO_JUMP_TARGET();
             }
@@ -1522,7 +1520,7 @@
             _PyErr_StackItem *exc_info = tstate->exc_info;
             _PyFrame_SetStackPointer(frame, stack_pointer);
             Py_XSETREF(exc_info->exc_value,
-                       PyStackRef_Is(exc_value, PyStackRef_None)
+                       PyStackRef_IsNone(exc_value)
                        ? NULL : PyStackRef_AsPyObjectSteal(exc_value));
             stack_pointer = _PyFrame_GetStackPointer(frame);
             stack_pointer += -1;
@@ -3110,13 +3108,7 @@
             oparg = CURRENT_OPARG();
             right = stack_pointer[-1];
             left = stack_pointer[-2];
-            #ifdef Py_GIL_DISABLED
-            // On free-threaded builds, objects are conditionally immortalized.
-            // So their bits don't always compare equally.
             int res = Py_Is(PyStackRef_AsPyObjectBorrow(left), PyStackRef_AsPyObjectBorrow(right)) ^ oparg;
-            #else
-            int res = PyStackRef_Is(left, right) ^ oparg;
-            #endif
             PyStackRef_CLOSE(left);
             PyStackRef_CLOSE(right);
             b = res ? PyStackRef_True : PyStackRef_False;
@@ -3320,7 +3312,7 @@
             _PyStackRef value;
             _PyStackRef b;
             value = stack_pointer[-1];
-            if (PyStackRef_Is(value, PyStackRef_None)) {
+            if (PyStackRef_IsNone(value)) {
                 b = PyStackRef_True;
             }
             else {
@@ -4562,7 +4554,7 @@
             _PyStackRef should_be_none;
             should_be_none = stack_pointer[-1];
             assert(STACK_LEVEL() == 2);
-            if (!PyStackRef_Is(should_be_none, PyStackRef_None)) {
+            if (!PyStackRef_IsNone(should_be_none)) {
                 _PyFrame_SetStackPointer(frame, stack_pointer);
                 PyErr_Format(PyExc_TypeError,
                              "__init__() should return None, not '%.200s'",
@@ -5643,7 +5635,7 @@
         case _GUARD_IS_TRUE_POP: {
             _PyStackRef flag;
             flag = stack_pointer[-1];
-            int is_true = PyStackRef_Is(flag, PyStackRef_True);
+            int is_true = PyStackRef_IsTrue(flag);
             stack_pointer += -1;
             assert(WITHIN_STACK_BOUNDS());
             if (!is_true) {
@@ -5656,7 +5648,7 @@
         case _GUARD_IS_FALSE_POP: {
             _PyStackRef flag;
             flag = stack_pointer[-1];
-            int is_false = PyStackRef_Is(flag, PyStackRef_False);
+            int is_false = PyStackRef_IsFalse(flag);
             stack_pointer += -1;
             assert(WITHIN_STACK_BOUNDS());
             if (!is_false) {
@@ -5669,7 +5661,7 @@
         case _GUARD_IS_NONE_POP: {
             _PyStackRef val;
             val = stack_pointer[-1];
-            int is_none = PyStackRef_Is(val, PyStackRef_None);
+            int is_none = PyStackRef_IsNone(val);
             if (!is_none) {
                 PyStackRef_CLOSE(val);
                 stack_pointer += -1;
@@ -5687,7 +5679,7 @@
         case _GUARD_IS_NOT_NONE_POP: {
             _PyStackRef val;
             val = stack_pointer[-1];
-            int is_none = PyStackRef_Is(val, PyStackRef_None);
+            int is_none = PyStackRef_IsNone(val);
             PyStackRef_CLOSE(val);
             stack_pointer += -1;
             assert(WITHIN_STACK_BOUNDS());
diff --git a/Python/generated_cases.c.h b/Python/generated_cases.c.h
index 182c9cf..36ec727 100644
--- a/Python/generated_cases.c.h
+++ b/Python/generated_cases.c.h
@@ -183,9 +183,7 @@
             /* Skip 1 cache entry */
             // _BINARY_OP_INPLACE_ADD_UNICODE
             {
-                #ifndef NDEBUG
                 PyObject *left_o = PyStackRef_AsPyObjectBorrow(left);
-                #endif
                 PyObject *right_o = PyStackRef_AsPyObjectBorrow(right);
                 int next_oparg;
                 #if TIER_ONE
@@ -195,7 +193,7 @@
                 next_oparg = CURRENT_OPERAND0();
                 #endif
                 _PyStackRef *target_local = &GETLOCAL(next_oparg);
-                DEOPT_IF(!PyStackRef_Is(*target_local, left), BINARY_OP);
+                DEOPT_IF(PyStackRef_AsPyObjectBorrow(*target_local) != left_o, BINARY_OP);
                 STAT_INC(BINARY_OP, hit);
                 /* Handle `left = left + right` or `left += right` for str.
                  *
@@ -3824,7 +3822,7 @@
             _PyStackRef should_be_none;
             should_be_none = stack_pointer[-1];
             assert(STACK_LEVEL() == 2);
-            if (!PyStackRef_Is(should_be_none, PyStackRef_None)) {
+            if (!PyStackRef_IsNone(should_be_none)) {
                 _PyFrame_SetStackPointer(frame, stack_pointer);
                 PyErr_Format(PyExc_TypeError,
                              "__init__() should return None, not '%.200s'",
@@ -4760,7 +4758,7 @@
             /* Skip 1 cache entry */
             _PyStackRef cond = POP();
             assert(PyStackRef_BoolCheck(cond));
-            int flag = PyStackRef_Is(cond, PyStackRef_False);
+            int flag = PyStackRef_IsFalse(cond);
             int offset = flag * oparg;
             RECORD_BRANCH_TAKEN(this_instr[1].cache, flag);
             INSTRUMENTED_JUMP(this_instr, next_instr + offset, PY_MONITORING_EVENT_BRANCH);
@@ -4774,7 +4772,7 @@
             INSTRUCTION_STATS(INSTRUMENTED_POP_JUMP_IF_NONE);
             /* Skip 1 cache entry */
             _PyStackRef value_stackref = POP();
-            int flag = PyStackRef_Is(value_stackref, PyStackRef_None);
+            int flag = PyStackRef_IsNone(value_stackref);
             int offset;
             if (flag) {
                 offset = oparg;
@@ -4796,7 +4794,7 @@
             /* Skip 1 cache entry */
             _PyStackRef value_stackref = POP();
             int offset;
-            int nflag = PyStackRef_Is(value_stackref, PyStackRef_None);
+            int nflag = PyStackRef_IsNone(value_stackref);
             if (nflag) {
                 offset = 0;
             }
@@ -4819,7 +4817,7 @@
             /* Skip 1 cache entry */
             _PyStackRef cond = POP();
             assert(PyStackRef_BoolCheck(cond));
-            int flag = PyStackRef_Is(cond, PyStackRef_True);
+            int flag = PyStackRef_IsTrue(cond);
             int offset = flag * oparg;
             RECORD_BRANCH_TAKEN(this_instr[1].cache, flag);
             INSTRUMENTED_JUMP(this_instr, next_instr + offset, PY_MONITORING_EVENT_BRANCH);
@@ -5040,13 +5038,7 @@
             _PyStackRef b;
             right = stack_pointer[-1];
             left = stack_pointer[-2];
-            #ifdef Py_GIL_DISABLED
-            // On free-threaded builds, objects are conditionally immortalized.
-            // So their bits don't always compare equally.
             int res = Py_Is(PyStackRef_AsPyObjectBorrow(left), PyStackRef_AsPyObjectBorrow(right)) ^ oparg;
-            #else
-            int res = PyStackRef_Is(left, right) ^ oparg;
-            #endif
             PyStackRef_CLOSE(left);
             PyStackRef_CLOSE(right);
             b = res ? PyStackRef_True : PyStackRef_False;
@@ -6663,7 +6655,7 @@
             _PyErr_StackItem *exc_info = tstate->exc_info;
             _PyFrame_SetStackPointer(frame, stack_pointer);
             Py_XSETREF(exc_info->exc_value,
-                       PyStackRef_Is(exc_value, PyStackRef_None)
+                       PyStackRef_IsNone(exc_value)
                        ? NULL : PyStackRef_AsPyObjectSteal(exc_value));
             stack_pointer = _PyFrame_GetStackPointer(frame);
             stack_pointer += -1;
@@ -6680,7 +6672,7 @@
             /* Skip 1 cache entry */
             cond = stack_pointer[-1];
             assert(PyStackRef_BoolCheck(cond));
-            int flag = PyStackRef_Is(cond, PyStackRef_False);
+            int flag = PyStackRef_IsFalse(cond);
             RECORD_BRANCH_TAKEN(this_instr[1].cache, flag);
             JUMPBY(oparg * flag);
             stack_pointer += -1;
@@ -6700,7 +6692,7 @@
             // _IS_NONE
             {
                 value = stack_pointer[-1];
-                if (PyStackRef_Is(value, PyStackRef_None)) {
+                if (PyStackRef_IsNone(value)) {
                     b = PyStackRef_True;
                 }
                 else {
@@ -6712,7 +6704,7 @@
             {
                 cond = b;
                 assert(PyStackRef_BoolCheck(cond));
-                int flag = PyStackRef_Is(cond, PyStackRef_True);
+                int flag = PyStackRef_IsTrue(cond);
                 RECORD_BRANCH_TAKEN(this_instr[1].cache, flag);
                 JUMPBY(oparg * flag);
             }
@@ -6733,7 +6725,7 @@
             // _IS_NONE
             {
                 value = stack_pointer[-1];
-                if (PyStackRef_Is(value, PyStackRef_None)) {
+                if (PyStackRef_IsNone(value)) {
                     b = PyStackRef_True;
                 }
                 else {
@@ -6745,7 +6737,7 @@
             {
                 cond = b;
                 assert(PyStackRef_BoolCheck(cond));
-                int flag = PyStackRef_Is(cond, PyStackRef_False);
+                int flag = PyStackRef_IsFalse(cond);
                 RECORD_BRANCH_TAKEN(this_instr[1].cache, flag);
                 JUMPBY(oparg * flag);
             }
@@ -6763,7 +6755,7 @@
             /* Skip 1 cache entry */
             cond = stack_pointer[-1];
             assert(PyStackRef_BoolCheck(cond));
-            int flag = PyStackRef_Is(cond, PyStackRef_True);
+            int flag = PyStackRef_IsTrue(cond);
             RECORD_BRANCH_TAKEN(this_instr[1].cache, flag);
             JUMPBY(oparg * flag);
             stack_pointer += -1;
@@ -7100,7 +7092,7 @@
                     gen_frame->previous = frame;
                     DISPATCH_INLINED(gen_frame);
                 }
-                if (PyStackRef_Is(v, PyStackRef_None) && PyIter_Check(receiver_o)) {
+                if (PyStackRef_IsNone(v) && PyIter_Check(receiver_o)) {
                     _PyFrame_SetStackPointer(frame, stack_pointer);
                     retval_o = Py_TYPE(receiver_o)->tp_iternext(receiver_o);
                     stack_pointer = _PyFrame_GetStackPointer(frame);
@@ -7880,7 +7872,7 @@
             /* Skip 2 cache entries */
             value = stack_pointer[-1];
             // This one is a bit weird, because we expect *some* failures:
-            DEOPT_IF(!PyStackRef_Is(value, PyStackRef_None), TO_BOOL);
+            DEOPT_IF(!PyStackRef_IsNone(value), TO_BOOL);
             STAT_INC(TO_BOOL, hit);
             res = PyStackRef_False;
             stack_pointer[-1] = res;
@@ -7955,7 +7947,7 @@
             _PyStackRef res;
             value = stack_pointer[-1];
             assert(PyStackRef_BoolCheck(value));
-            res = PyStackRef_Is(value, PyStackRef_False)
+            res = PyStackRef_IsFalse(value)
             ? PyStackRef_True : PyStackRef_False;
             stack_pointer[-1] = res;
             DISPATCH();
diff --git a/Tools/cases_generator/analyzer.py b/Tools/cases_generator/analyzer.py
index e02e07e..eca851e 100644
--- a/Tools/cases_generator/analyzer.py
+++ b/Tools/cases_generator/analyzer.py
@@ -548,7 +548,10 @@ NON_ESCAPING_FUNCTIONS = (
     "PyStackRef_FromPyObjectImmortal",
     "PyStackRef_FromPyObjectNew",
     "PyStackRef_FromPyObjectSteal",
-    "PyStackRef_Is",
+    "PyStackRef_IsExactly",
+    "PyStackRef_IsNone",
+    "PyStackRef_IsTrue",
+    "PyStackRef_IsFalse",
     "PyStackRef_IsNull",
     "PyStackRef_None",
     "PyStackRef_TYPE",