Method alias

src/analysis/pointsto/mod.rs:726–762

Check if two memory cells alias with each other. If they are from the same func, then perform intraproc alias analysis; otherwise, perform interproc alias analysis.

(&mut self, aid1: AliasId, aid2: AliasId)

    /// If they are from the same func, then perform intraproc alias analysis;
    /// otherwise, perform interproc alias analysis.
    pub fn alias(&mut self, aid1: AliasId, aid2: AliasId) -> ApproximateAliasKind {
        let AliasId {
            instance_id: id1,
            local: local1,
        } = aid1;
        let AliasId {
            instance_id: id2,
            local: local2,
        } = aid2;

        let instance1 = self
            .callgraph
            .index_to_instance(id1)
            .map(CallGraphNode::instance);
        let instance2 = self
            .callgraph
            .index_to_instance(id2)
            .map(CallGraphNode::instance);

        match (instance1, instance2) {
            (Some(instance1), Some(instance2)) => {
                let node1 = ConstraintNode::Place(Place::from(local1).as_ref());
                let node2 = ConstraintNode::Place(Place::from(local2).as_ref());
                if instance1.def_id() == instance2.def_id() {
                    if local1 == local2 {
                        return ApproximateAliasKind::Probably;
                    }
                    self.intraproc_alias(instance1, &node1, &node2)
                        .unwrap_or(ApproximateAliasKind::Unknown)
                } else {
                    self.interproc_alias(instance1, &node1, instance2, &node2)
                        .unwrap_or(ApproximateAliasKind::Unknown)
                }
            }
            _ => ApproximateAliasKind::Unknown,
        }
    }

    /// Check if `pointer` points to `pointee`.
    /// First get the pts(`pointer`),