pub type AllocState = Tree;Aliased Type§
pub struct AllocState {
pub(super) tag_mapping: UniKeyMap<BorTag>,
pub(super) nodes: UniValMap<Node>,
pub(super) locations: DedupRangeMap<LocationTree>,
pub(super) roots: SmallVec<[UniIndex; 2]>,
}Fields§
§tag_mapping: UniKeyMap<BorTag>Mapping from tags to keys. The key obtained can then be used in
any of the UniValMap relative to this allocation, i.e.
nodes, LocationTree::perms and LocationTree::wildcard_accesses
of the same Tree.
The parent-child relationship in Node is encoded in terms of these same
keys, so traversing the entire tree needs exactly one access to
tag_mapping.
nodes: UniValMap<Node>All nodes of this tree.
locations: DedupRangeMap<LocationTree>Associates with each location its state and wildcard access tracking.
roots: SmallVec<[UniIndex; 2]>Contains both the root of the main tree as well as the roots of the wildcard subtrees.
If we reborrow a reference which has wildcard provenance, then we do not know where in the tree to attach them. Instead we create a new additional tree for this allocation with this new reference as a root. We call this additional tree a wildcard subtree.
The actual structure should be a single tree but with wildcard provenance we approximate this with this ordered set of trees. Each wildcard subtree is the direct child of some exposed tag (that is smaller than the root), but we do not know which. This also means that it can only be the child of a tree that comes before it in the vec ensuring we don’t have any cycles in our approximated tree.
Sorted according to BorTag from low to high. This also means the main root is root[0].
Has array size 2 because that still ensures the minimum size for SmallVec.
Layout§
Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.
Size: 128 bytes