mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-07-07 19:35:27 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 8

GH-131798: Narrow the return type of isinstance for some known arguments in the JIT (GH-133172)

Browse source
This commit is contained in:
Tomas R. 2025-05-19 13:19:24 -04:00 • committed by GitHub
parent 9859791f9e
commit 8d490b3687
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
4 changed files with 152 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

20
Python/optimizer_bytecodes.c
View file

@ -890,6 +890,26 @@ dummy_func(void) {
}
}
op(_CALL_ISINSTANCE, (unused, unused, instance, cls -- res)) {
// the result is always a bool, but sometimes we can
// narrow it down to True or False
res = sym_new_type(ctx, &PyBool_Type);
PyTypeObject *inst_type = sym_get_type(instance);
PyTypeObject *cls_o = (PyTypeObject *)sym_get_const(ctx, cls);
if (inst_type && cls_o && sym_matches_type(cls, &PyType_Type)) {
// isinstance(inst, cls) where both inst and cls have
// known types, meaning we can deduce either True or False
// The below check is equivalent to PyObject_TypeCheck(inst, cls)
if (inst_type == cls_o || PyType_IsSubtype(inst_type, cls_o)) {
sym_set_const(res, Py_True);
}
else {
sym_set_const(res, Py_False);
}
}
}
op(_GUARD_IS_TRUE_POP, (flag -- )) {
if (sym_is_const(ctx, flag)) {
PyObject *value = sym_get_const(ctx, flag);