> Thanks! Do you have any plans for further inline caches?
Yeah, we are experimenting with some ideas here: https://bugs.python.org/issue42115.
> I was wondering if we could reverse the situation for slots again by adding slots support to the LOAD_ATTR opcode inline cache...
I think we can do it as long as we can detect easily if a given descriptor is immutable. The problem of mutability is this code:
class Descriptor:
pass
class C:
def __init__(self):
self.x = 1
x = Descriptor()
def f(o):
return o.x
o = C()
for i in range(10000):
assert f(o) == 1
Descriptor.__get__ = lambda self, instance, value: 2
Descriptor.__set__ = lambda *args: None
print(f(o))
In this case, if we do not skip the cache for mutable descriptors, the code will not reflect the new result (2 instead of 1). __slots__ are immutable descriptors so we should be good as long as we can detect them.