gh-92810: Reduce memory usage by ABCMeta.__subclasscheck__

[dolfinus]

• Issue: _abc._abc_subclasscheck has very poor performance and (I think) a memory leak #92810

Alternative implementation of #131914 which doesn't modify class attributes on every __subclasscheck__ call. Instead it checks in __new__ does current class have def __subclasses__(cls) overriden, and if so, enables case for scls in cls.__subclasses__(), which is disabled by default. To handle cases like Number -> Real -> Integral -> int; assert issubclass(int, Number) is True, method .register(subclass) is calling super().register(subclass) recursively.

For benchmark from #131914:

sudo ./python -m pyperf system tune
taskset -c 0 ./python benchmark.py --metaclass abc.ABCMeta --rounds 3 --classes 5000
taskset -c 0 ./python benchmark.py --metaclass _py_abc.ABCMeta --rounds 3 --classes 5000

Impl	Max memory before, MB	Max memory after, MB
_abc	6332	47
_py_abc	4423	58

Impl	Total time before	Total time after
_abc	19m 57s	2m 6s
_py_abc	17m 14s	6m 14s

Check	Impl	before	after	Impl	before	after
isinstance(child, Parent)	_abc	0.191us...0.213us 2MiB...15MiB	0.191us...0.193us 2MiB...15MiB	_py_abc	0.334us...0.348us 10MiB...23MiB	0.354us...0.362us 10MiB...23MiB
issubclass(Child, Parent)	_abc	0.175us...0.182us 0MiB	0.173us...0.174us 0MiB...1MiB	_py_abc	0.328us...0.329us 6MiB...8MiB	0.346us...0.363us 5MiB...8MiB
isinstance(child, Grandparent)	_abc	0.184us...0.188us 0MiB...2MiB	0.189us...0.192us 0MiB...1MiB	_py_abc	0.330us...0.333us 4MiB...6MiB	0.350us...0.356us 3MiB...6MiB
issubclass(Child, Grandparent)	_abc	0.166us...0.169us 0MiB	0.168us...0.172us 0MiB	_py_abc	0.326us...0.329us 0MiB...2MiB	0.324us...0.356us 0MiB...1MiB
not isinstance(child, Sibling)	_abc	0.184us...0.187us 2MiB...14MiB	0.188us...0.206us 1MiB...14MiB	_py_abc	0.564us...0.576us 14MiB...23MiB	0.628us...0.788us 13MiB...22MiB
not issubclass(Child, Sibling)	_abc	0.169us...0.169us 0MiB	0.171us...0.172us 0MiB...1MiB	_py_abc	0.531us...0.540us 10MiB...12MiB	0.555us...0.570us 7MiB...10MiB
not isinstance(child, Cousin)	_abc	0.186us...0.186us 1MiB...2MiB	0.185us...0.188us 1MiB...2MiB	_py_abc	0.572us...0.589us 8MiB...10MiB	0.607us...0.627us 6MiB...8MiB
not issubclass(Child, Cousin)	_abc	0.170us...0.172us 0MiB	0.169us...0.170us 0MiB...1MiB	_py_abc	0.534us...0.541us 5MiB...6MiB	0.558us...0.569us 3MiB...4MiB
not isinstance(child, Uncle)	_abc	8.188us...8.728us 5705MiB...6332MiB	0.193us...0.207us 0MiB...1MiB	_py_abc	13.098us...13.243us 3797MiB...4423MiB	0.607us...0.656us 5MiB
not issubclass(Child, Uncle)	_abc	8.071us...8.358us 5704MiB	0.176us...0.179us 0MiB	_py_abc	13.292us...13.371us 3794MiB...3795MiB	0.556us...0.582us 3MiB

Memory increment is measured during isinstance() / issubclass() calls, not during preparation, like class creation or registration.

Check	Impl	before	after	Impl	before	after
isinstance(child, Parent.register)	_abc	0.388us...0.390us 0MiB	0.402us...0.406us 0MiB	_py_abc	0.688us...0.693us 0MiB	0.795us...0.854us 0MiB
issubclass(Child, Parent.register)	_abc	0.240us...0.242us 0MiB	0.252us...0.256us 0MiB	_py_abc	0.681us...0.689us 0MiB	0.729us...0.763us 0MiB
isinstance(child, Grandparent.register)	_abc	0.184us 0MiB	0.190us...0.192us 0MiB	_py_abc	0.393us...0.397us 0MiB	0.426us...0.461us 0MiB
issubclass(Child, Grandparent.register)	_abc	0.170us...0.172us 0MiB	0.168us...0.171us 0MiB	_py_abc	0.384us...0.399us 0MiB	0.392us...0.513us 0MiB
not isinstance(child, Sibling.register)	_abc	0.044us 0MiB	0.041us...0.052us 1MiB	_py_abc	0.042us...0.043us 0MiB	0.043us...0.048us 2MiB
not issubclass(Child, Sibling.register)	_abc	0.028us 0MiB	0.028us 1MiB	_py_abc	0.028us 0MiB	0.029us...0.029us 2MiB
not isinstance(child, Cousin.register)	_abc	0.044us 0MiB	0.041us...0.042us 2MiB	_py_abc	0.044us 0MiB	0.044us...0.045us 3MiB
not issubclass(Child, Cousin.register)	_abc	0.028us 0MiB	0.028us 2MiB	_py_abc	0.028us 0MiB	0.027us...0.029us 3MiB
not isinstance(child, Uncle.register)	_abc	0.372us...0.382us 0MiB	0.367us...0.375us 2MiB...3MiB	_py_abc	1.352us...1.434us 0MiB	1.588us...1.629us 4MiB
not issubclass(Child, Uncle.register)	_abc	0.356us...0.365us 0MiB	0.358us...0.365us 2MiB	_py_abc	1.306us...1.316us 0MiB	1.483us...1.544us 4MiB

Check	Impl	before	after	Impl	before	after
isinstance(child, Parent.__subclasses__)	_abc	0.202us...0.209us 0MiB	0.210us...0.212us 0MiB	_py_abc	0.463us...0.468us 0MiB	0.483us...0.505us 0MiB
issubclass(Child, Parent.__subclasses__)	_abc	0.189us...0.194us 0MiB	0.194us...0.196us 0MiB	_py_abc	0.457us...0.460us 0MiB	0.476us...0.497us 0MiB
isinstance(child, Grandparent.__subclasses__)	_abc	0.199us...0.200us 0MiB	0.203us...0.212us 0MiB	_py_abc	0.463us...0.468us 0MiB	0.490us...0.531us 0MiB
issubclass(Child, Grandparent.__subclasses__)	_abc	0.184us...0.188us 0MiB	0.185us...0.189us 0MiB	_py_abc	0.451us...0.455us 0MiB	0.472us...0.499us 0MiB
not isinstance(child, Sibling.__subclasses__)	_abc	0.044us 0MiB	0.042us 0MiB	_py_abc	0.043us 0MiB	0.045us...0.045us 1MiB
not issubclass(Child, Sibling.__subclasses__)	_abc	0.028us 0MiB	0.028us...0.029us 0MiB	_py_abc	0.027us...0.028us 0MiB	0.029us 1MiB
not isinstance(child, Cousin.__subclasses__)	_abc	0.044us...0.046us 0MiB	0.042us 0MiB	_py_abc	0.044us 0MiB	0.043us...0.045us 1MiB
not issubclass(Child, Cousin.__subclasses__)	_abc	0.028us 0MiB	0.028us 0MiB	_py_abc	0.028us 0MiB	0.029us 1MiB
not isinstance(child, Uncle.__subclasses__)	_abc	0.233us...0.238us 0MiB	0.238us...0.243us 0MiB	_py_abc	0.878us...0.884us 0MiB	0.935us...1.009us 2MiB
not issubclass(Child, Uncle.__subclasses__)	_abc	0.216us...0.223us 0MiB	0.218us...0.219us 0MiB	_py_abc	0.835us...0.845us 0MiB	0.857us...0.915us 2MiB

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