IN_ARCHIVE_ROOT doesn't fit all that well into the Access API as currently implemented. It is treated as a different kind of "root" but still a "root" rather than "heap" location.

We propose to move support for loading from an archive to the CollectedHeap API. The idea is that the materialization of these objects could be seen as similar to a new allocation, and that "loading from the archive" should be largely opaque to the rest of the VM. Removing it from Access simplifies that API somewhat, and the associated addition to the CollectedHeap API should be quite narrow.

A different approach would be to treat it as another category of ON_xxx_OOP_REF. This doesn't do much to simplify the Access API though.