GraphWriter.h revision 8c836ce4f86713376b626e30765494f0a4f7e4b3 
1//===-- Support/GraphWriter.h - Write a graph to a .dot file ---*- C++ -*--===//
2//
3// This file defines a simple interface that can be used to print out generic
4// LLVM graphs to ".dot" files.  "dot" is a tool that is part of the AT&T
5// graphviz package (http://www.research.att.com/sw/tools/graphviz/) which can
6// be used to turn the files output by this interface into a variety of
7// different graphics formats.
8//
9// Graphs do not need to implement any interface past what is already required
10// by the GraphTraits template, but they can choose to implement specializations
11// of the DOTGraphTraits template if they want to customize the graphs output in
12// any way.
13//
14//===----------------------------------------------------------------------===//
15
16#ifndef SUPPORT_GRAPHWRITER_H
17#define SUPPORT_GRAPHWRITER_H
18
19#include "Support/DOTGraphTraits.h"
20#include "Support/GraphTraits.h"
21#include <ostream>
22
23namespace DOT {  // Private functions...
24  inline std::string EscapeString(const std::string &Label) {
25    std::string Str(Label);
26    for (unsigned i = 0; i != Str.length(); ++i)
27      switch (Str[i]) {
28      case '\n':
29        Str.insert(Str.begin()+i, '\\');  // Escape character...
30        ++i;
31        Str[i] = 'n';
32        break;
33      case '\t':
34        Str.insert(Str.begin()+i, ' ');  // Convert to two spaces
35        ++i;
36        Str[i] = ' ';
37        break;
38      case '\\':
39        if (i+1 != Str.length() && Str[i+1] == 'l')
40          break;  // don't disturb \l
41      case '{': case '}':
42      case '<': case '>':
43        Str.insert(Str.begin()+i, '\\');  // Escape character...
44        ++i;  // don't infinite loop
45        break;
46      }
47    return Str;
48  }
49}
50
51template<typename GraphType>
52class GraphWriter {
53  std::ostream &O;
54  const GraphType &G;
55
56  typedef DOTGraphTraits<GraphType>           DOTTraits;
57  typedef GraphTraits<GraphType>              GTraits;
58  typedef typename GTraits::NodeType          NodeType;
59  typedef typename GTraits::nodes_iterator    node_iterator;
60  typedef typename GTraits::ChildIteratorType child_iterator;
61public:
62  GraphWriter(std::ostream &o, const GraphType &g,
63              const std::string &Name) : O(o), G(g) {
64    if (Name.empty())
65      O << "digraph foo {\n";        // Graph name doesn't matter
66    else
67      O << "digraph " << Name << " {\n";
68
69    std::string GraphName = DOTTraits::getGraphName(G);
70    if (!GraphName.empty())
71      O << "\tlabel=\"" << DOT::EscapeString(GraphName) << "\";\n";
72    O << DOTTraits::getGraphProperties(G);
73    O << "\n";
74
75    writeNodes();
76  }
77
78  ~GraphWriter() {
79    // Finish off the graph
80    O << "}\n";
81  }
82
83  void writeNodes() {
84    // Loop over the graph, printing it out...
85    for (node_iterator I = GTraits::nodes_begin(G), E = GTraits::nodes_end(G);
86         I != E; ++I)
87      writeNode(&*I);
88  }
89
90  void writeNode(NodeType *Node) {
91    std::string NodeAttributes = DOTTraits::getNodeAttributes(Node);
92
93    O << "\tNode" << (void*)Node << " [shape=record,";
94    if (!NodeAttributes.empty()) O << NodeAttributes << ",";
95    O << "label=\"{"
96      << DOT::EscapeString(DOTTraits::getNodeLabel(Node, G));
97
98    // Print out the fields of the current node...
99    child_iterator EI = GTraits::child_begin(Node);
100    child_iterator EE = GTraits::child_end(Node);
101    if (EI != EE) {
102      O << "|{";
103
104      for (unsigned i = 0; EI != EE && i != 64; ++EI, ++i) {
105        if (i) O << "|";
106        O << "<g" << i << ">" << DOTTraits::getEdgeSourceLabel(Node, EI);
107      }
108
109      if (EI != EE)
110        O << "|truncated...";
111      O << "}";
112    }
113    O << "}\"];\n";   // Finish printing the "node" line
114
115    // Output all of the edges now
116    EI = GTraits::child_begin(Node);
117    for (unsigned i = 0; EI != EE && i != 64; ++EI, ++i)
118      writeEdge(Node, i, EI);
119  }
120
121  void writeEdge(NodeType *Node, unsigned edgeidx, child_iterator EI) {
122    if (NodeType *TargetNode = *EI) {
123      O << "\tNode" << (void*)Node << ":g" << edgeidx << " -> Node"
124        << (void*)TargetNode;
125      if (DOTTraits::edgeTargetsEdgeSource(Node, EI)) {
126        child_iterator TargetIt = DOTTraits::getEdgeTarget(Node, EI);
127
128        // Figure out which edge this targets...
129        unsigned Offset = std::distance(GTraits::child_begin(TargetNode),
130                                        TargetIt);
131        if (Offset > 64) Offset = 64;  // Targetting the truncated part?
132        O << ":g" << Offset;
133      }
134
135      std::string EdgeAttributes = DOTTraits::getEdgeAttributes(Node, EI);
136      if (!EdgeAttributes.empty())
137        O << "[" << EdgeAttributes << "]";
138      O << ";\n";
139    }
140  }
141};
142
143template<typename GraphType>
144std::ostream &WriteGraph(std::ostream &O, const GraphType &G,
145                         const std::string &Name = "") {
146  // Start the graph emission process...
147  GraphWriter<GraphType> W(O, G, Name);
148  return O;
149}
150
151#endif
152