1 // Copyright 2014 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 /// This module provides linkage between rustc::middle::graph and
12 /// libgraphviz traits.
14 // For clarity, rename the graphviz crate locally to dot.
16 use graphviz::IntoCow;
20 use front::map as ast_map;
23 pub type Node<'a> = (cfg::CFGIndex, &'a cfg::CFGNode);
24 pub type Edge<'a> = &'a cfg::CFGEdge;
26 pub struct LabelledCFG<'a, 'ast: 'a> {
27 pub ast_map: &'a ast_map::Map<'ast>,
28 pub cfg: &'a cfg::CFG,
30 /// `labelled_edges` controls whether we emit labels on the edges
31 pub labelled_edges: bool,
34 fn replace_newline_with_backslash_l(s: String) -> String {
35 // Replacing newlines with \\l causes each line to be left-aligned,
36 // improving presentation of (long) pretty-printed expressions.
38 let mut s = s.replace("\n", "\\l");
39 // Apparently left-alignment applies to the line that precedes
40 // \l, not the line that follows; so, add \l at end of string
41 // if not already present, ensuring last line gets left-aligned
43 let mut last_two: Vec<_> =
44 s.chars().rev().take(2).collect();
46 if last_two != ['\\', 'l'] {
55 impl<'a, 'ast> dot::Labeller<'a, Node<'a>, Edge<'a>> for LabelledCFG<'a, 'ast> {
56 fn graph_id(&'a self) -> dot::Id<'a> { dot::Id::new(&self.name[..]).unwrap() }
58 fn node_id(&'a self, &(i,_): &Node<'a>) -> dot::Id<'a> {
59 dot::Id::new(format!("N{}", i.node_id())).unwrap()
62 fn node_label(&'a self, &(i, n): &Node<'a>) -> dot::LabelText<'a> {
63 if i == self.cfg.entry {
64 dot::LabelText::LabelStr("entry".into_cow())
65 } else if i == self.cfg.exit {
66 dot::LabelText::LabelStr("exit".into_cow())
67 } else if n.data.id() == ast::DUMMY_NODE_ID {
68 dot::LabelText::LabelStr("(dummy_node)".into_cow())
70 let s = self.ast_map.node_to_string(n.data.id());
71 // left-aligns the lines
72 let s = replace_newline_with_backslash_l(s);
73 dot::LabelText::EscStr(s.into_cow())
77 fn edge_label(&self, e: &Edge<'a>) -> dot::LabelText<'a> {
78 let mut label = String::new();
79 if !self.labelled_edges {
80 return dot::LabelText::EscStr(label.into_cow());
82 let mut put_one = false;
83 for (i, &node_id) in e.data.exiting_scopes.iter().enumerate() {
85 label.push_str(",\\l");
89 let s = self.ast_map.node_to_string(node_id);
90 // left-aligns the lines
91 let s = replace_newline_with_backslash_l(s);
92 label.push_str(&format!("exiting scope_{} {}",
96 dot::LabelText::EscStr(label.into_cow())
100 impl<'a> dot::GraphWalk<'a, Node<'a>, Edge<'a>> for &'a cfg::CFG {
101 fn nodes(&'a self) -> dot::Nodes<'a, Node<'a>> {
102 let mut v = Vec::new();
103 self.graph.each_node(|i, nd| { v.push((i, nd)); true });
106 fn edges(&'a self) -> dot::Edges<'a, Edge<'a>> {
107 self.graph.all_edges().iter().collect()
109 fn source(&'a self, edge: &Edge<'a>) -> Node<'a> {
110 let i = edge.source();
111 (i, self.graph.node(i))
113 fn target(&'a self, edge: &Edge<'a>) -> Node<'a> {
114 let i = edge.target();
115 (i, self.graph.node(i))
119 impl<'a, 'ast> dot::GraphWalk<'a, Node<'a>, Edge<'a>> for LabelledCFG<'a, 'ast>
121 fn nodes(&'a self) -> dot::Nodes<'a, Node<'a>> { self.cfg.nodes() }
122 fn edges(&'a self) -> dot::Edges<'a, Edge<'a>> { self.cfg.edges() }
123 fn source(&'a self, edge: &Edge<'a>) -> Node<'a> { self.cfg.source(edge) }
124 fn target(&'a self, edge: &Edge<'a>) -> Node<'a> { self.cfg.target(edge) }