hasattr() performance is bad on a slot that has no value

Bug report

Bug description:

Compare these two timeit invocations:

$ python3.14 -m timeit -s 'class Test: pass' -s 't = Test()' 'hasattr(t,"x")'
10000000 loops, best of 5: 33.5 nsec per loop
$ python3.14 -m timeit -s 'class Test: __slots__ = ("x",)' -s 't = Test()' 'hasattr(t,"x")'
1000000 loops, best of 5: 241 nsec per loop

Observe that in the case where Test.x is a slot, hasattr takes 241 ns to return False while it only takes 33.5 ns when there is no Test.x slot.

Peter Bierma advised me to file an issue when I asked about this in Discourse.

CPython versions tested on:

3.14, 3.13, 3.12

Operating systems tested on:

Linux

Commencez par reproduire les deux commandes timeit de Python 3.14 de l’issue et comparez le cas de l’attribut manquant avec le cas du slot sans valeur. Suivez la recherche du slot et le chemin hasattr responsables de la différence. Le travail est terminé lorsque le cas du slot sans valeur est amélioré de manière mesurable sans modifier le résultat False de hasattr ni le comportement existant.