gh-155486: Allow non-compact integers in TO_BOOL_INT

Lib/test/test_capi/test_opt.py

@@ -4875,6 +4875,27 @@ def f(n):
         self.assertLessEqual(count_ops(ex, "_POP_TOP"), 3)
         self.assertIn("_POP_TOP_NOP", uops)
 
+    def test_to_bool_noncompact_int(self):
+        # gh-155486: non-compact exact integer should remain specialized
+        # as _TO_BOOL_INT in Tier 2.
+        def f(n, value=1 << 100):
+            for _ in range(n):
+                if not value:
+                    return 0
+                # The second check should reuse the exact-int type established by the first guard.
+                if not value:
+                    return 0
+            return 1
+
+        res, ex = self._run_with_optimizer(f, TIER2_THRESHOLD)
+        self.assertEqual(res, 1)
+        self.assertIsNotNone(ex)
+        uops = get_opnames(ex)
+        self.assertIn("_TO_BOOL_INT", uops)
+        self.assertLessEqual(count_ops(ex, "_GUARD_TOS_EXACT_INT"), 1)
+        self.assertLessEqual(count_ops(ex, "_POP_TOP"), 3)
+        self.assertIn("_POP_TOP_NOP", uops)
+
     def test_to_bool_list(self):
         def f(n):
             for i in range(n):

Python/bytecodes.c

@@ -526,7 +526,7 @@ dummy_func(
         }
 
         macro(TO_BOOL_INT) =
-            _GUARD_TOS_INT + unused/1 + unused/2 + _TO_BOOL_INT + _POP_TOP_INT;
+            _GUARD_TOS_EXACT_INT + unused/1 + unused/2 + _TO_BOOL_INT + _POP_TOP_INT;
 
         op(_GUARD_NOS_LIST, (nos, unused -- nos, unused)) {
             PyObject *o = PyStackRef_AsPyObjectBorrow(nos);
@@ -643,6 +643,11 @@ dummy_func(
             EXIT_IF(!_PyLong_CheckExactAndCompact(value_o));
         }
 
+        op(_GUARD_TOS_EXACT_INT, (value -- value)) {
+            PyObject *value_o = PyStackRef_AsPyObjectBorrow(value);
+            EXIT_IF(!PyLong_CheckExact(value_o));
+        }
+
         op(_GUARD_NOS_OVERFLOWED, (left, unused -- left, unused)) {
             PyObject *left_o = PyStackRef_AsPyObjectBorrow(left);
             assert(Py_TYPE(left_o) == &PyLong_Type);

Python/optimizer_bytecodes.c

@@ -217,6 +217,13 @@ dummy_func(void) {
         }
     }
 
+    op(_GUARD_TOS_EXACT_INT, (value -- value)) {
+        if (sym_matches_type(value, &PyLong_Type)) {
+            ADD_OP(_NOP, 0, 0);
+        }
+        sym_set_type(value, &PyLong_Type);
+    }
+
     op(_GUARD_NOS_INT, (left, unused -- left, unused)) {
         if (sym_is_compact_int(left)) {
             ADD_OP(_NOP, 0, 0);