LOAD_ATTR_INSTANCE_VALUE needs to check the validity of the objects embedded values array.
Currently, it does that by computing the offset of the valid byte.
Instead we could store the offset in the inline cache as LOAD_ATTR_INSTANCE_VALUE has several inline cache entries to spare.

The check is done in the _CHECK_MANAGED_OBJECT_HAS_VALUES uop.

Linked PRs

• gh-152063: Cache the offset of the inline values 'valid' byte in LOAD_ATTR #153122