gh-134584: Cleanups for refcount elimination #135860

[Fidget-Spinner]

This cleans up PR #135860.

Mostly just moving code around.

• Issue: Eliminate redundant refcounting in the JIT #134584

[corona10]

lgtm!

[markshannon]

Can you make a separate PRs for fixing the leak? I'd like to get that in ASAP.

For the larger changes:

• There is no need for _POP_TOP_NOT_NULL as it still needs to check for immortal objects and NULL is immortal
• The changes to the code generator need more explanation and maybe a new issue.

[bedevere-app]

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

[Fidget-Spinner]

Can you make a separate PRs for fixing the leak? I'd like to get that in ASAP.

I can't without a partial revert. The problem is that we don't allow live inputs at ERROR_IF. This PR simply changes the ERROR_IF behavior to close all live inputs.

The rest of this PR to the cases generator is just moving stuff around if you take a closer look. I mainly had to expose the close_variable function as it was previously a nested one.

[Zheaoli]

Just for personal thought(correct me plz if I'm wrong)

The root cause about this refleak is related with the wrong position about ERROR_IF. In this case, in old generated code, the arg will leak after ERROR_IF

So the core point about this PR is the behavior change "raise an exception when here's live variable on TOS -> close all the live variable"

So we can mark the stack INPUT_DEAD safety after ERROR_IF after this PR

[Fidget-Spinner]

@Zheaoli yes you're right

[Fidget-Spinner]

Can you make a separate PRs for fixing the leak? I'd like to get that in ASAP.

For the larger changes:

• There is no need for _POP_TOP_NOT_NULL as it still needs to check for immortal objects and NULL is immortal
• The changes to the code generator need more explanation and maybe a new issue.

I removed all the changes to the code generator and POP_TOP_NOT_NULL. As such, this review is now stale.

I removed all the changes that were contentious. This PR is now just a re-implementation of #135860. So it's fine now as that was previously approved and merged.

[corona10]

Since the current change is only a reimplementation of _CALL_TUPLE_1 from #135860, it looks good to me.

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot AMD64 Windows PGO NoGIL 3.x (tier-1) has failed when building commit e02a35c.

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/1622/builds/3361) and take a look at the build logs.
4. Check if the failure is related to this commit (e02a35c) 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/1622/builds/3361

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

Click to see traceback logs

remote: Enumerating objects: 30, done. remote: Counting objects: 3% (1/27) remote: Counting objects: 7% (2/27) remote: Counting objects: 11% (3/27) remote: Counting objects: 14% (4/27) remote: Counting objects: 18% (5/27) remote: Counting objects: 22% (6/27) remote: Counting objects: 25% (7/27) remote: Counting objects: 29% (8/27) remote: Counting objects: 33% (9/27) remote: Counting objects: 37% (10/27) remote: Counting objects: 40% (11/27) remote: Counting objects: 44% (12/27) remote: Counting objects: 48% (13/27) remote: Counting objects: 51% (14/27) remote: Counting objects: 55% (15/27) remote: Counting objects: 59% (16/27) remote: Counting objects: 62% (17/27) remote: Counting objects: 66% (18/27) remote: Counting objects: 70% (19/27) remote: Counting objects: 74% (20/27) remote: Counting objects: 77% (21/27) remote: Counting objects: 81% (22/27) remote: Counting objects: 85% (23/27) remote: Counting objects: 88% (24/27) remote: Counting objects: 92% (25/27) remote: Counting objects: 96% (26/27) remote: Counting objects: 100% (27/27) remote: Counting objects: 100% (27/27), done. remote: Compressing objects: 7% (1/13) remote: Compressing objects: 15% (2/13) remote: Compressing objects: 23% (3/13) remote: Compressing objects: 30% (4/13) remote: Compressing objects: 38% (5/13) remote: Compressing objects: 46% (6/13) remote: Compressing objects: 53% (7/13) remote: Compressing objects: 61% (8/13) remote: Compressing objects: 69% (9/13) remote: Compressing objects: 76% (10/13) remote: Compressing objects: 84% (11/13) remote: Compressing objects: 92% (12/13) remote: Compressing objects: 100% (13/13) remote: Compressing objects: 100% (13/13), done. remote: Total 30 (delta 16), reused 14 (delta 14), pack-reused 3 (from 2)  From https://github.com/python/cpython * branch main -> FETCH_HEAD Note: switching to 'e02a35c36535330bb86b4067104f537aa6da00e4'. You are in 'detached HEAD' state. You can look around, make experimental changes and commit them, and you can discard any commits you make in this state without impacting any branches by switching back to a branch. If you want to create a new branch to retain commits you create, you may do so (now or later) by using -c with the switch command. Example: git switch -c <new-branch-name> Or undo this operation with: git switch - Turn off this advice by setting config variable advice.detachedHead to false HEAD is now at e02a35c3653 gh-134584: Cleanups for GH-135860 (GH-142604) Switched to and reset branch 'main' Could Not Find C:\Users\Administrator\buildarea\3.x.itamaro-win64-srv-22-aws.nogil.pgo\build\PCbuild\*.pgc Could Not Find C:\Users\Administrator\buildarea\3.x.itamaro-win64-srv-22-aws.nogil.pgo\build\Lib\*.pyc '"C:\Users\Administrator\buildarea\3.x.itamaro-win64-srv-22-aws.nogil.pgo\build\PCbuild\\..\python.bat"' is not recognized as an internal or external command, operable program or batch file. Could Not Find C:\Users\Administrator\buildarea\3.x.itamaro-win64-srv-22-aws.nogil.pgo\build\PCbuild\*.pgc Could Not Find C:\Users\Administrator\buildarea\3.x.itamaro-win64-srv-22-aws.nogil.pgo\build\Lib\*.pyc '"C:\Users\Administrator\buildarea\3.x.itamaro-win64-srv-22-aws.nogil.pgo\build\PCbuild\\..\python.bat"' is not recognized as an internal or external command, operable program or batch file. Could Not Find C:\Users\Administrator\buildarea\3.x.itamaro-win64-srv-22-aws.nogil.pgo\build\Lib\*.pyc The system cannot find the file specified. Could Not Find C:\Users\Administrator\buildarea\3.x.itamaro-win64-srv-22-aws.nogil.pgo\build\PCbuild\python*.zip Could Not Find C:\Users\Administrator\buildarea\3.x.itamaro-win64-srv-22-aws.nogil.pgo\build\PCbuild\*.pgc Could Not Find C:\Users\Administrator\buildarea\3.x.itamaro-win64-srv-22-aws.nogil.pgo\build\Lib\*.pyc Could Not Find C:\Users\Administrator\buildarea\3.x.itamaro-win64-srv-22-aws.nogil.pgo\build\PCbuild\python*.zip