PERF: #48212 Cache the results of get_block_type (1.1.x)

[Code0x58]

This gave a ~5% performance boost. It looks like things started to slow down in this area after 0.19.2 with more costly type checking.

As mentioned on #48212, I'm upgrading a large codebase and 1.1.x is the limit I can get to without significant changes (upgrading of codebase, libraries, and environments/machines), so this is a great stepping stone. I'd appreciate if this would get accepted as a patch release for it, I'm happy to go through the other 1.x branches to apply the change once a pattern is confirmed.

It looks like the automated CI run doesn't like trying to run on/for 1.1.x, so I'll have a run when I swap machines, but imagine I'll have to make a branch based on master sooner rather than later to get confidence from CI.

• closes PERF: get_block_type heavy use could benefit performance improvements #48212 (Replace xxxx with the Github issue number) - not closing as targeting a 1.1.x
• Tests added and passed if fixing a bug or adding a new feature
• All code checks passed.
• Added type annotations to new arguments/methods/functions.
• Added an entry in the latest doc/source/whatsnew/vX.X.X.rst file if fixing a bug or adding a new feature.

[phofl]

Hi, thanks for looking into this.

We do not backport anything to our old branches except the newest released branch. This is currently 1.4.x

Please always submit the prs to main. This is necessary to see that everything passes before we backport some changes. That said, in general we do not backport performance improvements if there is not a good reason for it (large performance decrease that can be isolated really well)