1//===- llvm/Support/GraphWriter.h - Write graph to a .dot file --*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file defines a simple interface that can be used to print out generic
10// LLVM graphs to ".dot" files. "dot" is a tool that is part of the AT&T
11// graphviz package (http://www.research.att.com/sw/tools/graphviz/) which can
12// be used to turn the files output by this interface into a variety of
13// different graphics formats.
14//
15// Graphs do not need to implement any interface past what is already required
16// by the GraphTraits template, but they can choose to implement specializations
17// of the DOTGraphTraits template if they want to customize the graphs output in
18// any way.
19//
20//===----------------------------------------------------------------------===//
21
22#ifndef LLVM_SUPPORT_GRAPHWRITER_H
23#define LLVM_SUPPORT_GRAPHWRITER_H
24
25#include "llvm/ADT/GraphTraits.h"
26#include "llvm/ADT/StringRef.h"
27#include "llvm/ADT/Twine.h"
28#include "llvm/Support/DOTGraphTraits.h"
29#include "llvm/Support/FileSystem.h"
30#include "llvm/Support/raw_ostream.h"
31#include <iterator>
32#include <string>
33#include <type_traits>
34#include <vector>
35
36namespace llvm {
37
38namespace DOT { // Private functions...
39
40std::string EscapeString(const std::string &Label);
41
42/// Get a color string for this node number. Simply round-robin selects
43/// from a reasonable number of colors.
44StringRef getColorString(unsigned NodeNumber);
45
46} // end namespace DOT
47
48namespace GraphProgram {
49
50enum Name {
51 DOT,
52 FDP,
53 NEATO,
54 TWOPI,
55 CIRCO
56};
57
58} // end namespace GraphProgram
59
60bool DisplayGraph(StringRef Filename, bool wait = true,
61 GraphProgram::Name program = GraphProgram::DOT);
62
63template<typename GraphType>
64class GraphWriter {
65 raw_ostream &O;
66 const GraphType &G;
67 bool RenderUsingHTML = false;
68
69 using DOTTraits = DOTGraphTraits<GraphType>;
70 using GTraits = GraphTraits<GraphType>;
71 using NodeRef = typename GTraits::NodeRef;
72 using node_iterator = typename GTraits::nodes_iterator;
73 using child_iterator = typename GTraits::ChildIteratorType;
74 DOTTraits DTraits;
75
76 static_assert(std::is_pointer_v<NodeRef>,
77 "FIXME: Currently GraphWriter requires the NodeRef type to be "
78 "a pointer.\nThe pointer usage should be moved to "
79 "DOTGraphTraits, and removed from GraphWriter itself.");
80
81 // Writes the edge labels of the node to O and returns true if there are any
82 // edge labels not equal to the empty string "".
83 bool getEdgeSourceLabels(raw_ostream &O, NodeRef Node) {
84 child_iterator EI = GTraits::child_begin(Node);
85 child_iterator EE = GTraits::child_end(Node);
86 bool hasEdgeSourceLabels = false;
87
88 if (RenderUsingHTML)
89 O << "</tr><tr>";
90
91 for (unsigned i = 0; EI != EE && i != 64; ++EI, ++i) {
92 std::string label = DTraits.getEdgeSourceLabel(Node, EI);
93
94 if (label.empty())
95 continue;
96
97 hasEdgeSourceLabels = true;
98
99 if (RenderUsingHTML)
100 O << "<td colspan=\"1\" port=\"s" << i << "\">" << label << "</td>";
101 else {
102 if (i)
103 O << "|";
104
105 O << "<s" << i << ">" << DOT::EscapeString(Label: label);
106 }
107 }
108
109 if (EI != EE && hasEdgeSourceLabels) {
110 if (RenderUsingHTML)
111 O << "<td colspan=\"1\" port=\"s64\">truncated...</td>";
112 else
113 O << "|<s64>truncated...";
114 }
115
116 return hasEdgeSourceLabels;
117 }
118
119public:
120 GraphWriter(raw_ostream &o, const GraphType &g, bool SN) : O(o), G(g) {
121 DTraits = DOTTraits(SN);
122 RenderUsingHTML = DTraits.renderNodesUsingHTML();
123 }
124
125 void writeGraph(const std::string &Title = "") {
126 // Output the header for the graph...
127 writeHeader(Title);
128
129 // Emit all of the nodes in the graph...
130 writeNodes();
131
132 // Output any customizations on the graph
133 DOTGraphTraits<GraphType>::addCustomGraphFeatures(G, *this);
134
135 // Output the end of the graph
136 writeFooter();
137 }
138
139 void writeHeader(const std::string &Title) {
140 std::string GraphName(DTraits.getGraphName(G));
141
142 if (!Title.empty())
143 O << "digraph \"" << DOT::EscapeString(Label: Title) << "\" {\n";
144 else if (!GraphName.empty())
145 O << "digraph \"" << DOT::EscapeString(Label: GraphName) << "\" {\n";
146 else
147 O << "digraph unnamed {\n";
148
149 if (DTraits.renderGraphFromBottomUp())
150 O << "\trankdir=\"BT\";\n";
151
152 if (!Title.empty())
153 O << "\tlabel=\"" << DOT::EscapeString(Label: Title) << "\";\n";
154 else if (!GraphName.empty())
155 O << "\tlabel=\"" << DOT::EscapeString(Label: GraphName) << "\";\n";
156 O << DTraits.getGraphProperties(G);
157 O << "\n";
158 }
159
160 void writeFooter() {
161 // Finish off the graph
162 O << "}\n";
163 }
164
165 void writeNodes() {
166 // Loop over the graph, printing it out...
167 for (const auto Node : nodes<GraphType>(G))
168 if (!isNodeHidden(Node))
169 writeNode(Node);
170 }
171
172 bool isNodeHidden(NodeRef Node) { return DTraits.isNodeHidden(Node, G); }
173
174 void writeNode(NodeRef Node) {
175 std::string NodeAttributes = DTraits.getNodeAttributes(Node, G);
176
177 O << "\tNode" << static_cast<const void *>(Node) << " [shape=";
178 if (RenderUsingHTML)
179 O << "none,";
180 else
181 O << "record,";
182
183 if (!NodeAttributes.empty()) O << NodeAttributes << ",";
184 O << "label=";
185
186 if (RenderUsingHTML) {
187 // Count the numbewr of edges out of the node to determine how
188 // many columns to span (max 64)
189 unsigned ColSpan = 0;
190 child_iterator EI = GTraits::child_begin(Node);
191 child_iterator EE = GTraits::child_end(Node);
192 for (; EI != EE && ColSpan != 64; ++EI, ++ColSpan)
193 ;
194 if (ColSpan == 0)
195 ColSpan = 1;
196 // Include truncated messages when counting.
197 if (EI != EE)
198 ++ColSpan;
199 O << "<<table border=\"0\" cellborder=\"1\" cellspacing=\"0\""
200 << " cellpadding=\"0\"><tr><td align=\"text\" colspan=\"" << ColSpan
201 << "\">";
202 } else
203 O << "\"{";
204
205 if (!DTraits.renderGraphFromBottomUp()) {
206 if (RenderUsingHTML)
207 O << DTraits.getNodeLabel(Node, G) << "</td>";
208 else
209 O << DOT::EscapeString(Label: DTraits.getNodeLabel(Node, G));
210
211 // If we should include the address of the node in the label, do so now.
212 std::string Id = DTraits.getNodeIdentifierLabel(Node, G);
213 if (!Id.empty())
214 O << "|" << DOT::EscapeString(Label: Id);
215
216 std::string NodeDesc = DTraits.getNodeDescription(Node, G);
217 if (!NodeDesc.empty())
218 O << "|" << DOT::EscapeString(Label: NodeDesc);
219 }
220
221 std::string edgeSourceLabels;
222 raw_string_ostream EdgeSourceLabels(edgeSourceLabels);
223 bool hasEdgeSourceLabels = getEdgeSourceLabels(O&: EdgeSourceLabels, Node);
224
225 if (hasEdgeSourceLabels) {
226 if (!DTraits.renderGraphFromBottomUp())
227 if (!RenderUsingHTML)
228 O << "|";
229
230 if (RenderUsingHTML)
231 O << edgeSourceLabels;
232 else
233 O << "{" << edgeSourceLabels << "}";
234
235 if (DTraits.renderGraphFromBottomUp())
236 if (!RenderUsingHTML)
237 O << "|";
238 }
239
240 if (DTraits.renderGraphFromBottomUp()) {
241 if (RenderUsingHTML)
242 O << DTraits.getNodeLabel(Node, G);
243 else
244 O << DOT::EscapeString(Label: DTraits.getNodeLabel(Node, G));
245
246 // If we should include the address of the node in the label, do so now.
247 std::string Id = DTraits.getNodeIdentifierLabel(Node, G);
248 if (!Id.empty())
249 O << "|" << DOT::EscapeString(Label: Id);
250
251 std::string NodeDesc = DTraits.getNodeDescription(Node, G);
252 if (!NodeDesc.empty())
253 O << "|" << DOT::EscapeString(Label: NodeDesc);
254 }
255
256 if (DTraits.hasEdgeDestLabels()) {
257 O << "|{";
258
259 unsigned i = 0, e = DTraits.numEdgeDestLabels(Node);
260 for (; i != e && i != 64; ++i) {
261 if (i) O << "|";
262 O << "<d" << i << ">"
263 << DOT::EscapeString(Label: DTraits.getEdgeDestLabel(Node, i));
264 }
265
266 if (i != e)
267 O << "|<d64>truncated...";
268 O << "}";
269 }
270
271 if (RenderUsingHTML)
272 O << "</tr></table>>";
273 else
274 O << "}\"";
275 O << "];\n"; // Finish printing the "node" line
276
277 // Output all of the edges now
278 child_iterator EI = GTraits::child_begin(Node);
279 child_iterator EE = GTraits::child_end(Node);
280 for (unsigned i = 0; EI != EE && i != 64; ++EI, ++i)
281 if (!DTraits.isNodeHidden(*EI, G))
282 writeEdge(Node, edgeidx: i, EI);
283 for (; EI != EE; ++EI)
284 if (!DTraits.isNodeHidden(*EI, G))
285 writeEdge(Node, edgeidx: 64, EI);
286 }
287
288 void writeEdge(NodeRef Node, unsigned edgeidx, child_iterator EI) {
289 if (NodeRef TargetNode = *EI) {
290 int DestPort = -1;
291 if (DTraits.edgeTargetsEdgeSource(Node, EI)) {
292 child_iterator TargetIt = DTraits.getEdgeTarget(Node, EI);
293
294 // Figure out which edge this targets...
295 unsigned Offset =
296 (unsigned)std::distance(GTraits::child_begin(TargetNode), TargetIt);
297 DestPort = static_cast<int>(Offset);
298 }
299
300 if (DTraits.getEdgeSourceLabel(Node, EI).empty())
301 edgeidx = -1;
302
303 emitEdge(SrcNodeID: static_cast<const void*>(Node), SrcNodePort: edgeidx,
304 DestNodeID: static_cast<const void*>(TargetNode), DestNodePort: DestPort,
305 Attrs: DTraits.getEdgeAttributes(Node, EI, G));
306 }
307 }
308
309 /// emitSimpleNode - Outputs a simple (non-record) node
310 void emitSimpleNode(const void *ID, const std::string &Attr,
311 const std::string &Label, unsigned NumEdgeSources = 0,
312 const std::vector<std::string> *EdgeSourceLabels = nullptr) {
313 O << "\tNode" << ID << "[ ";
314 if (!Attr.empty())
315 O << Attr << ",";
316 O << " label =\"";
317 if (NumEdgeSources) O << "{";
318 O << DOT::EscapeString(Label);
319 if (NumEdgeSources) {
320 O << "|{";
321
322 for (unsigned i = 0; i != NumEdgeSources; ++i) {
323 if (i) O << "|";
324 O << "<s" << i << ">";
325 if (EdgeSourceLabels) O << DOT::EscapeString(Label: (*EdgeSourceLabels)[i]);
326 }
327 O << "}}";
328 }
329 O << "\"];\n";
330 }
331
332 /// emitEdge - Output an edge from a simple node into the graph...
333 void emitEdge(const void *SrcNodeID, int SrcNodePort,
334 const void *DestNodeID, int DestNodePort,
335 const std::string &Attrs) {
336 if (SrcNodePort > 64) return; // Eminating from truncated part?
337 if (DestNodePort > 64) DestNodePort = 64; // Targeting the truncated part?
338
339 O << "\tNode" << SrcNodeID;
340 if (SrcNodePort >= 0)
341 O << ":s" << SrcNodePort;
342 O << " -> Node" << DestNodeID;
343 if (DestNodePort >= 0 && DTraits.hasEdgeDestLabels())
344 O << ":d" << DestNodePort;
345
346 if (!Attrs.empty())
347 O << "[" << Attrs << "]";
348 O << ";\n";
349 }
350
351 /// getOStream - Get the raw output stream into the graph file. Useful to
352 /// write fancy things using addCustomGraphFeatures().
353 raw_ostream &getOStream() {
354 return O;
355 }
356};
357
358template<typename GraphType>
359raw_ostream &WriteGraph(raw_ostream &O, const GraphType &G,
360 bool ShortNames = false,
361 const Twine &Title = "") {
362 // Start the graph emission process...
363 GraphWriter<GraphType> W(O, G, ShortNames);
364
365 // Emit the graph.
366 W.writeGraph(Title.str());
367
368 return O;
369}
370
371std::string createGraphFilename(const Twine &Name, int &FD);
372
373/// Writes graph into a provided @c Filename.
374/// If @c Filename is empty, generates a random one.
375/// \return The resulting filename, or an empty string if writing
376/// failed.
377template <typename GraphType>
378std::string WriteGraph(const GraphType &G, const Twine &Name,
379 bool ShortNames = false,
380 const Twine &Title = "",
381 std::string Filename = "") {
382 int FD;
383 if (Filename.empty()) {
384 Filename = createGraphFilename(Name: Name.str(), FD);
385 } else {
386 std::error_code EC = sys::fs::openFileForWrite(
387 Name: Filename, ResultFD&: FD, Disp: sys::fs::CD_CreateAlways, Flags: sys::fs::OF_Text);
388
389 // Writing over an existing file is not considered an error.
390 if (EC == std::errc::file_exists) {
391 errs() << "file exists, overwriting" << "\n";
392 } else if (EC) {
393 errs() << "error writing into file" << "\n";
394 return "";
395 } else {
396 errs() << "writing to the newly created file " << Filename << "\n";
397 }
398 }
399 raw_fd_ostream O(FD, /*shouldClose=*/ true);
400
401 if (FD == -1) {
402 errs() << "error opening file '" << Filename << "' for writing!\n";
403 return "";
404 }
405
406 llvm::WriteGraph(O, G, ShortNames, Title);
407 errs() << " done. \n";
408
409 return Filename;
410}
411
412/// DumpDotGraph - Just dump a dot graph to the user-provided file name.
413#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
414template <typename GraphType>
415LLVM_DUMP_METHOD void
416dumpDotGraphToFile(const GraphType &G, const Twine &FileName,
417 const Twine &Title, bool ShortNames = false,
418 const Twine &Name = "") {
419 llvm::WriteGraph(G, Name, ShortNames, Title, FileName.str());
420}
421#endif
422
423/// ViewGraph - Emit a dot graph, run 'dot', run gv on the postscript file,
424/// then cleanup. For use from the debugger.
425///
426template<typename GraphType>
427void ViewGraph(const GraphType &G, const Twine &Name,
428 bool ShortNames = false, const Twine &Title = "",
429 GraphProgram::Name Program = GraphProgram::DOT) {
430 std::string Filename = llvm::WriteGraph(G, Name, ShortNames, Title);
431
432 if (Filename.empty())
433 return;
434
435 DisplayGraph(Filename, wait: false, program: Program);
436}
437
438} // end namespace llvm
439
440#endif // LLVM_SUPPORT_GRAPHWRITER_H
441