gh-143732: allow dict subclasses to be specialized

[kumaraditya303]

• Issue: Broader specialization in the Specializing Adaptive Interpreter for better JIT performance #143732

This is revival of #132383 which allowed specialization for dict subclasses which do not override __getitem__. This PR also allows specialization for dict subclasses which do not override __setitem__.

This is primarily targeted for defaultdict which is the most performance critical subclass of dict.

[kumaraditya303]

@markshannon Can you take a look at this? I'd like get this in time for the beta release.

[markshannon]

Looks good overall.
The old uops need to be removed and some assertions may no longer be valid.

Also, take care with recorded types. Only strengthen type information on proven or guards, not recorded information.

[markshannon]

GitHub doen't put comments in order, it seems. The "above" in the comments refers to earlier lines, not earlier comments.

[kumaraditya303]

I still think the assert(PyDict_Check(dict)); asserts should be removed.

I removed the assertions now and added watchers for all cases.

I have made the requested changes; please review again

[bedevere-app]

Thanks for making the requested changes!

@markshannon: please review the changes made to this pull request.

[read-the-docs-community]

Documentation build overview

📚 cpython-previews | 🛠️ Build #32488413 | 📁 Comparing b40e922 against main (b413bc7)

🔍 Preview build

12 files changed · ± 12 modified

±Modified

• contents.html
• download.html
• genindex-D.html
• genindex-H.html
• genindex-Symbols.html
• genindex-all.html
• library/faulthandler.html
• library/functools.html
• library/http.server.html
• library/tomllib.html
• and 2 more...

[markshannon]

I still think we need more watchers. Sorry, I should have spotted that in the last review.

[bedevere-app]

When you're done making the requested changes, leave the comment: I have made the requested changes; please review again.

And if you don't make the requested changes, you will be poked with soft cushions!

[kumaraditya303]

Looks like the CI is affected by the Ubuntu outage today.

[kumaraditya303]

I have made the requested changes; please review again

[bedevere-app]

Thanks for making the requested changes!

@markshannon: please review the changes made to this pull request.

[markshannon]

This looks good now. Thanks.

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot AMD64 Debian root 3.x (tier-1) has failed when building commit 5847931.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/345/builds/14120) and take a look at the build logs.
4. Check if the failure is related to this commit (5847931) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/345/builds/14120

Summary of the results of the build (if available):

==

Click to see traceback logs

Traceback (most recent call last):
File "/root/buildarea/3.x.angelico-debian-amd64/build/Lib/test/support/__init__.py", line 948, in gc_collect
gc.collect()
~~~~~~~~~~^^ResourceWarning: unclosed file <_io.FileIO name=11 mode='wb' closefd=True>