Skip to content

gh-131798: JIT: Assign type to sliced string/list/tuple #134671

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 5 commits into
base: main
Choose a base branch
from

Conversation

fluhus
Copy link
Contributor

@fluhus fluhus commented May 25, 2025

Slicing a string/list/tuple always returns the same type.
Make the optimizer assign a string/list/tuple type to the result of slicing a string/list/tuple.

@brandtbucher

// Slicing a string/list/tuple always returns the same type.
PyTypeObject *type = sym_get_type(container);
if (type == &PyUnicode_Type ||
type == &PyList_Type ||
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Suggested change
type == &PyList_Type ||
type == &PyBytes_Type ||
type == &PyList_Type ||

I do not know whether slicing a bytes object occurs often enough to add PyBytes_Type here (and whether the jit slows down if we add more cases here), but if I understand correctly slicing bytes (or bytearray) results in a bytes (or bytearray) so we could add them.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Projects
None yet
Development

Successfully merging this pull request may close these issues.

2 participants