Function points_to_paths_to_param

src/analysis/pointsto/mod.rs:1158–1176

Find the points-to paths from the given node to the closure parameters (upvar). A points-to path is like [([], node), ([Field(0)], node1), ([Filed(1)], node2), ..., ([Field(n)], parameter)] Current points-to analysis does not support relations like `from _9.1 to _9`, which means pts(_9)⊇pts(_9.1) but not vice versa. The upvars in closures usually share the following pattern: _9 = &_1.1; // pts(_9

(
    node: ConstraintNode<'tcx>,
    body: &'tcx Body<'tcx>,
    points_to_map: &PointsToMap<'tcx>,
)

fn projected_base_ty<'tcx>(
    local: Local,
    pts: &FxHashSet<ConstraintNode<'tcx>>,
    points_to_map: &PointsToMap<'tcx>,
    body: &Body<'tcx>,
    tcx: TyCtxt<'tcx>,
) -> Option<rustc_middle::ty::Ty<'tcx>> {
    if is_parameter(local, body) {
        return Some(body.local_decls[local].ty);
    }
    let local_node = ConstraintNode::Place(Place::from(local).as_ref());
    pts.iter()
        .chain(points_to_map.get(&local_node).into_iter().flatten())
        .find_map(|node| match node {
            ConstraintNode::Alloc(place) | ConstraintNode::Place(place)
                if is_parameter(place.local, body) =>
            {
                Some(place.ty(body, tcx).ty)
            }
            _ => None,
        })
}