Fix some bugs

1. We cannot exit after unpacking indices, as the stack contains tagged ints now which may lead to a crash. We must insert a guard for the type before unpacking indices.
2. It is possible for an indice to not fit in a tagged int, in which case we must deopt.
3. Recorded values do not always mean that that's the actual type we will see at runtime. So we must guard on that as well.

Author: Fidget-Spinner

Include/internal/pycore_optimizer.h

@@ -303,6 +303,7 @@ extern void _Py_uop_sym_set_recorded_type(JitOptContext *ctx, JitOptRef sym, PyT
 extern void _Py_uop_sym_set_recorded_gen_func(JitOptContext *ctx, JitOptRef ref, PyFunctionObject *value);
 extern PyCodeObject *_Py_uop_sym_get_probable_func_code(JitOptRef sym);
 extern PyObject *_Py_uop_sym_get_probable_value(JitOptRef sym);
+extern PyTypeObject * _Py_uop_sym_get_probable_type(JitOptRef ref);
 
 extern void _Py_uop_abstractcontext_init(JitOptContext *ctx);
 extern void _Py_uop_abstractcontext_fini(JitOptContext *ctx);

Include/internal/pycore_stackref.h

@@ -427,11 +427,17 @@ PyStackRef_IsTaggedInt(_PyStackRef i)
     return (i.bits & Py_TAG_BITS) == Py_INT_TAG;
 }
 
+static inline bool
+PyStackRef_CanTagInt(intptr_t i)
+{
+    return Py_ARITHMETIC_RIGHT_SHIFT(intptr_t, (intptr_t)(((uintptr_t)i) << Py_TAGGED_SHIFT),
+                                     Py_TAGGED_SHIFT) == i;
+}
+
 static inline _PyStackRef
 PyStackRef_TagInt(intptr_t i)
 {
-    assert(Py_ARITHMETIC_RIGHT_SHIFT(intptr_t, (intptr_t)(((uintptr_t)i) << Py_TAGGED_SHIFT),
-                                     Py_TAGGED_SHIFT) == i);
+    assert(PyStackRef_CanTagInt(i));
     return (_PyStackRef){ .bits = ((((uintptr_t)i) << Py_TAGGED_SHIFT) | Py_INT_TAG) };
 }