GraphWriter.h revision 9106a588060085316895a9b256909d795c2f5b5e 
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/DepthFirstIterator.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>
52std::ostream &WriteGraph(std::ostream &O, const GraphType &G) {
53  typedef DOTGraphTraits<GraphType>  DOTTraits;
54  typedef GraphTraits<GraphType>     GTraits;
55  typedef typename GTraits::NodeType NodeType;
56
57  O << "digraph foo {\n"         // Graph name doesn't matter
58    << "\tsize=\"7.5,10\";\n";   // Size to fit on a page
59
60  std::string GraphName = DOTTraits::getGraphName(G);
61  if (!GraphName.empty())
62    O << "\tlabel=\"" << DOT::EscapeString(GraphName) << "\";\n";
63  O << "\n";
64
65  // Loop over the graph in DFO, printing it out...
66  NodeType *Root = GTraits::getEntryNode(G);
67  for (df_iterator<GraphType> I = df_begin(G), E = df_end(G); I != E; ++I) {
68    NodeType *Node = *I;
69
70    std::string NodeAttributes = DOTTraits::getNodeAttributes(Node);
71
72    O << "\tNode" << (void*)Node << " [";
73    if (!NodeAttributes.empty()) O << NodeAttributes << ",";
74    O << "shape=record,label=\"{"
75      << DOT::EscapeString(DOTTraits::getNodeLabel(Node, G));
76
77    // Print out the fields of the current node...
78    typename GTraits::ChildIteratorType EI = GTraits::child_begin(Node);
79    typename GTraits::ChildIteratorType EE = GTraits::child_end(Node);
80    if (EI != EE) {
81      O << "|{";
82
83      for (unsigned i = 0; EI != EE && i != 64; ++EI, ++i) {
84        if (i) O << "|";
85        O << "<g" << i << ">" << DOTTraits::getEdgeSourceLabel(Node, EI);
86      }
87
88      if (EI != EE)
89        O << "|truncated...";
90      O << "}";
91    }
92    O << "}\"];\n";   // Finish printing the "node" line
93
94    // Output all of the edges now
95    EI = GTraits::child_begin(Node);
96    for (unsigned i = 0; EI != EE && i != 64; ++EI, ++i) {
97      NodeType *TargetNode = *EI;
98      O << "\tNode" << (void*)Node << ":g" << i << " -> Node"
99        << (void*)TargetNode;
100      if (DOTTraits::edgeTargetsEdgeSource(Node, EI)) {
101        typename GTraits::ChildIteratorType TargetIt =
102          DOTTraits::getEdgeTarget(Node, EI);
103        // Figure out which edge this targets...
104        unsigned Offset = std::distance(GTraits::child_begin(TargetNode),
105                                        TargetIt);
106        if (Offset > 64) Offset = 64;  // Targetting the trancated part?
107        O << ":g" << Offset;
108      }
109
110      std::string EdgeAttributes = DOTTraits::getEdgeAttributes(Node, EI);
111      if (!EdgeAttributes.empty())
112        O << "[" << EdgeAttributes << "]";
113      O << ";\n";
114    }
115  }
116
117  // Finish off the graph
118  O << "}\n";
119  return O;
120}
121
122#endif
123