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 use std::borrow::IntoCow;
16 // For clarity, rename the graphviz crate locally to dot.
24 pub type Node<'a> = (cfg::CFGIndex, &'a cfg::CFGNode);
25 pub type Edge<'a> = &'a cfg::CFGEdge;
27 pub struct LabelledCFG<'a, 'ast: 'a> {
28 pub ast_map: &'a ast_map::Map<'ast>,
29 pub cfg: &'a cfg::CFG,
31 /// `labelled_edges` controls whether we emit labels on the edges
32 pub labelled_edges: bool,
35 fn replace_newline_with_backslash_l(s: String) -> String {
36 // Replacing newlines with \\l causes each line to be left-aligned,
37 // improving presentation of (long) pretty-printed expressions.
39 let mut s = s.replace("\n", "\\l");
40 // Apparently left-alignment applies to the line that precedes
41 // \l, not the line that follows; so, add \l at end of string
42 // if not already present, ensuring last line gets left-aligned
44 let mut last_two: Vec<_> =
45 s.chars().rev().take(2).collect();
47 if last_two != ['\\', 'l'] {
56 impl<'a, 'ast> dot::Labeller<'a, Node<'a>, Edge<'a>> for LabelledCFG<'a, 'ast> {
57 fn graph_id(&'a self) -> dot::Id<'a> { dot::Id::new(&self.name[]).ok().unwrap() }
59 fn node_id(&'a self, &(i,_): &Node<'a>) -> dot::Id<'a> {
60 dot::Id::new(format!("N{}", i.node_id())).ok().unwrap()
63 fn node_label(&'a self, &(i, n): &Node<'a>) -> dot::LabelText<'a> {
64 if i == self.cfg.entry {
65 dot::LabelText::LabelStr("entry".into_cow())
66 } else if i == self.cfg.exit {
67 dot::LabelText::LabelStr("exit".into_cow())
68 } else if n.data.id == ast::DUMMY_NODE_ID {
69 dot::LabelText::LabelStr("(dummy_node)".into_cow())
71 let s = self.ast_map.node_to_string(n.data.id);
72 // left-aligns the lines
73 let s = replace_newline_with_backslash_l(s);
74 dot::LabelText::EscStr(s.into_cow())
78 fn edge_label(&self, e: &Edge<'a>) -> dot::LabelText<'a> {
79 let mut label = String::new();
80 if !self.labelled_edges {
81 return dot::LabelText::EscStr(label.into_cow());
83 let mut put_one = false;
84 for (i, &node_id) in e.data.exiting_scopes.iter().enumerate() {
86 label.push_str(",\\l");
90 let s = self.ast_map.node_to_string(node_id);
91 // left-aligns the lines
92 let s = replace_newline_with_backslash_l(s);
93 label.push_str(&format!("exiting scope_{} {}",
97 dot::LabelText::EscStr(label.into_cow())
101 impl<'a> dot::GraphWalk<'a, Node<'a>, Edge<'a>> for &'a cfg::CFG {
102 fn nodes(&'a self) -> dot::Nodes<'a, Node<'a>> {
103 let mut v = Vec::new();
104 self.graph.each_node(|i, nd| { v.push((i, nd)); true });
107 fn edges(&'a self) -> dot::Edges<'a, Edge<'a>> {
108 self.graph.all_edges().iter().collect()
110 fn source(&'a self, edge: &Edge<'a>) -> Node<'a> {
111 let i = edge.source();
112 (i, self.graph.node(i))
114 fn target(&'a self, edge: &Edge<'a>) -> Node<'a> {
115 let i = edge.target();
116 (i, self.graph.node(i))
120 impl<'a, 'ast> dot::GraphWalk<'a, Node<'a>, Edge<'a>> for LabelledCFG<'a, 'ast>
122 fn nodes(&'a self) -> dot::Nodes<'a, Node<'a>> { self.cfg.nodes() }
123 fn edges(&'a self) -> dot::Edges<'a, Edge<'a>> { self.cfg.edges() }
124 fn source(&'a self, edge: &Edge<'a>) -> Node<'a> { self.cfg.source(edge) }
125 fn target(&'a self, edge: &Edge<'a>) -> Node<'a> { self.cfg.target(edge) }