src/librustc/dep_graph/prev.rs

   1 // Copyright 2017 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.
   4 //
   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.
  10
  11 use ich::Fingerprint;
  12 use rustc_data_structures::fx::FxHashMap;
  13 use super::dep_node::DepNode;
  14 use super::serialized::{SerializedDepGraph, SerializedDepNodeIndex};
  15
  16 #[derive(Debug, RustcEncodable, RustcDecodable)]
  17 pub struct PreviousDepGraph {
  18     data: SerializedDepGraph,
  19     index: FxHashMap<DepNode, SerializedDepNodeIndex>,
  20 }
  21
  22 impl PreviousDepGraph {
  23     pub fn new(data: SerializedDepGraph) -> PreviousDepGraph {
  24         let index: FxHashMap<_, _> = data.nodes
  25             .iter_enumerated()
  26             .map(|(idx, &(dep_node, _))| (dep_node, idx))
  27             .collect();
  28         PreviousDepGraph { data, index }
  29     }
  30
  31     #[inline]
  32     pub fn edges_from(&self,
  33                       dep_node: &DepNode)
  34                       -> Option<(&[SerializedDepNodeIndex], SerializedDepNodeIndex)> {
  35         self.index
  36             .get(dep_node)
  37             .map(|&node_index| {
  38                 (self.data.edge_targets_from(node_index), node_index)
  39             })
  40     }
  41
  42     #[inline]
  43     pub fn index_to_node(&self, dep_node_index: SerializedDepNodeIndex) -> DepNode {
  44         self.data.nodes[dep_node_index].0
  45     }
  46
  47     #[inline]
  48     pub fn fingerprint_of(&self, dep_node: &DepNode) -> Option<Fingerprint> {
  49         self.index
  50             .get(dep_node)
  51             .map(|&node_index| self.data.nodes[node_index].1)
  52     }
  53
  54     #[inline]
  55     pub fn fingerprint_by_index(&self,
  56                                 dep_node_index: SerializedDepNodeIndex)
  57                                 -> Fingerprint {
  58         self.data.nodes[dep_node_index].1
  59     }
  60 }