1724119 - Avoid using pinned atoms in JS debugger

Status: RESOLVED WORKSFORME

(Core :: JavaScript Engine, task, P2)

Description

[Ted Campbell [:tcampbell]]

There are still a few places in the JS debugger that use PinAtom when we should consider it deprecated.

This is not ideal because a "pinned" atom string is kept alive forever and requires deprecated GC machinery to do so. Instead, if there is a finite set we pin here, they should be made "well-known" atoms built into spidermonkey. These still live forever, but with less complexity.

1. Make sure you can build spidermonkey using this guide: https://firefox-source-docs.mozilla.org/js/build.html
2. Ensure the few strings we need are in the CommonPropertyNames.h list.
3. Update DebuggerEnvironment::CallData::typeGetter to use cx->names().... similar to here
4. Make sure ./mach jit-tests debug passes on your computer after these fixes.

Additionally, DebuggerEnvironment::CallData::scopeKindGetter could be fixed in a similar way too.

Comment 1

[Jared Hirsch [:jhirsch] (he/him) (Needinfo please)]

Hey there! 👋 Grabbing this issue. I work on the desktop front-end, and I'd like to get a little bit of experience working with JS engine C++. Feel free to steal this back if it gets prioritized up, or if someone's already working on it.

Comment 2

[BugBot [:suhaib / :marco/ :calixte]]

This good-first-bug hasn't had any activity for 2 months, it is automatically unassigned.
For more information, please visit auto_nag documentation.

Comment 3

[Jan de Mooij [:jandem]]

This has been fixed in other bugs.