1 // Copyright 2012-2015 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 use rustc_data_structures::fx::FxHashMap;
12 use rustc_data_structures::graph::{Direction, INCOMING, Graph, NodeIndex, OUTGOING};
16 pub struct DepGraphQuery {
17 pub graph: Graph<DepNode, ()>,
18 pub indices: FxHashMap<DepNode, NodeIndex>,
22 pub fn new(nodes: &[DepNode],
23 edges: &[(DepNode, DepNode)])
25 let mut graph = Graph::new();
26 let mut indices = FxHashMap();
28 indices.insert(node.clone(), graph.next_node_index());
29 graph.add_node(node.clone());
32 for &(ref source, ref target) in edges {
33 let source = indices[source];
34 let target = indices[target];
35 graph.add_edge(source, target, ());
44 pub fn contains_node(&self, node: &DepNode) -> bool {
45 self.indices.contains_key(&node)
48 pub fn nodes(&self) -> Vec<&DepNode> {
49 self.graph.all_nodes()
55 pub fn edges(&self) -> Vec<(&DepNode,&DepNode)> {
56 self.graph.all_edges()
58 .map(|edge| (edge.source(), edge.target()))
59 .map(|(s, t)| (self.graph.node_data(s),
60 self.graph.node_data(t)))
64 fn reachable_nodes(&self, node: &DepNode, direction: Direction) -> Vec<&DepNode> {
65 if let Some(&index) = self.indices.get(node) {
66 self.graph.depth_traverse(index, direction)
67 .map(|s| self.graph.node_data(s))
74 /// All nodes reachable from `node`. In other words, things that
75 /// will have to be recomputed if `node` changes.
76 pub fn transitive_successors(&self, node: &DepNode) -> Vec<&DepNode> {
77 self.reachable_nodes(node, OUTGOING)
80 /// All nodes that can reach `node`.
81 pub fn transitive_predecessors(&self, node: &DepNode) -> Vec<&DepNode> {
82 self.reachable_nodes(node, INCOMING)
85 /// Just the outgoing edges from `node`.
86 pub fn immediate_successors(&self, node: &DepNode) -> Vec<&DepNode> {
87 if let Some(&index) = self.indices.get(&node) {
88 self.graph.successor_nodes(index)
89 .map(|s| self.graph.node_data(s))