bpo-45026: More compact range iterator (alt)

[serhiy-storchaka]

Keep the current and stop values instead of initial start, index and initial length.

https://bugs.python.org/issue45026

#89189

[bedevere-bot]

🤖 New build scheduled with the buildbot fleet by @ambv for commit 177da8c 🤖

If you want to schedule another build, you need to add the ":hammer: test-with-buildbots" label again.

[ambv]

The refleak here looks real:

test_range leaked [7, 7, 7] references, sum=21 test_range leaked [5, 5, 5] memory blocks, sum=15 

[serhiy-storchaka]

@ambv please do not merge until I run benchmarks.

[bedevere-bot]

🤖 New build scheduled with the buildbot fleet by @ambv for commit dced0e6 🤖

If you want to schedule another build, you need to add the ":hammer: test-with-buildbots" label again.

[github-actions]

This PR is stale because it has been open for 30 days with no activity.

[serhiy-storchaka]

See also #27986.