Function mmtk::util::metadata::vo_bit::bcopy_vo_bit_from_mark_bit

pub(crate) fn bcopy_vo_bit_from_mark_bit<VM: VMBinding>(
    start: Address,
    size: usize
)

Bulk copy VO bits from side mark bits. Some VMs require the VO bits to be available during tracing. However, some GC algorithms (such as Immix) cannot clear VO bits for dead objects only. As an alternative, this function copies the mark bits metadata to VO bits. The caller needs to ensure the mark bits are set exactly wherever VO bits need to be set before calling this function.