1//===-- SelectionDAGPrinter.cpp - Implement SelectionDAG::viewGraph() -----===//
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 implements the SelectionDAG::viewGraph method.
10//
11//===----------------------------------------------------------------------===//
12
13#include "ScheduleDAGSDNodes.h"
14#include "llvm/ADT/DenseSet.h"
15#include "llvm/ADT/StringExtras.h"
16#include "llvm/CodeGen/MachineFunction.h"
17#include "llvm/CodeGen/SelectionDAG.h"
18#include "llvm/Support/Debug.h"
19#include "llvm/Support/GraphWriter.h"
20#include "llvm/Support/raw_ostream.h"
21using namespace llvm;
22
23#define DEBUG_TYPE "dag-printer"
24
25namespace llvm {
26 template<>
27 struct DOTGraphTraits<SelectionDAG*> : public DefaultDOTGraphTraits {
28
29 explicit DOTGraphTraits(bool isSimple=false) :
30 DefaultDOTGraphTraits(isSimple) {}
31
32 static bool hasEdgeDestLabels() {
33 return true;
34 }
35
36 static unsigned numEdgeDestLabels(const void *Node) {
37 return ((const SDNode *) Node)->getNumValues();
38 }
39
40 static std::string getEdgeDestLabel(const void *Node, unsigned i) {
41 return ((const SDNode *) Node)->getValueType(ResNo: i).getEVTString();
42 }
43
44 template<typename EdgeIter>
45 static std::string getEdgeSourceLabel(const void *Node, EdgeIter I) {
46 return itostr(I - SDNodeIterator::begin(N: (const SDNode *) Node));
47 }
48
49 /// edgeTargetsEdgeSource - This method returns true if this outgoing edge
50 /// should actually target another edge source, not a node. If this method
51 /// is implemented, getEdgeTarget should be implemented.
52 template<typename EdgeIter>
53 static bool edgeTargetsEdgeSource(const void *Node, EdgeIter I) {
54 return true;
55 }
56
57 /// getEdgeTarget - If edgeTargetsEdgeSource returns true, this method is
58 /// called to determine which outgoing edge of Node is the target of this
59 /// edge.
60 template<typename EdgeIter>
61 static EdgeIter getEdgeTarget(const void *Node, EdgeIter I) {
62 SDNode *TargetNode = *I;
63 SDNodeIterator NI = SDNodeIterator::begin(N: TargetNode);
64 std::advance(NI, I.getNode()->getOperand(I.getOperand()).getResNo());
65 return NI;
66 }
67
68 static std::string getGraphName(const SelectionDAG *G) {
69 return std::string(G->getMachineFunction().getName());
70 }
71
72 static bool renderGraphFromBottomUp() {
73 return true;
74 }
75
76 static std::string getNodeIdentifierLabel(const SDNode *Node,
77 const SelectionDAG *Graph) {
78 std::string R;
79 raw_string_ostream OS(R);
80#ifndef NDEBUG
81 OS << 't' << Node->PersistentId;
82#else
83 OS << static_cast<const void *>(Node);
84#endif
85 return R;
86 }
87
88 /// If you want to override the dot attributes printed for a particular
89 /// edge, override this method.
90 template<typename EdgeIter>
91 static std::string getEdgeAttributes(const void *Node, EdgeIter EI,
92 const SelectionDAG *Graph) {
93 SDValue Op = EI.getNode()->getOperand(EI.getOperand());
94 EVT VT = Op.getValueType();
95 if (VT == MVT::Glue)
96 return "color=red,style=bold";
97 else if (VT == MVT::Other)
98 return "color=blue,style=dashed";
99 return "";
100 }
101
102
103 static std::string getSimpleNodeLabel(const SDNode *Node,
104 const SelectionDAG *G) {
105 std::string Result = Node->getOperationName(G);
106 {
107 raw_string_ostream OS(Result);
108 Node->print_details(OS, G);
109 }
110 return Result;
111 }
112 std::string getNodeLabel(const SDNode *Node, const SelectionDAG *Graph);
113 static std::string getNodeAttributes(const SDNode *N,
114 const SelectionDAG *Graph) {
115#ifndef NDEBUG
116 const std::string &Attrs = Graph->getGraphAttrs(N);
117 if (!Attrs.empty()) {
118 if (Attrs.find("shape=") == std::string::npos)
119 return std::string("shape=Mrecord,") + Attrs;
120 else
121 return Attrs;
122 }
123#endif
124 return "shape=Mrecord";
125 }
126
127 static void addCustomGraphFeatures(SelectionDAG *G,
128 GraphWriter<SelectionDAG*> &GW) {
129 GW.emitSimpleNode(ID: nullptr, Attr: "plaintext=circle", Label: "GraphRoot");
130 if (G->getRoot().getNode())
131 GW.emitEdge(SrcNodeID: nullptr, SrcNodePort: -1, DestNodeID: G->getRoot().getNode(), DestNodePort: G->getRoot().getResNo(),
132 Attrs: "color=blue,style=dashed");
133 }
134 };
135}
136
137std::string DOTGraphTraits<SelectionDAG*>::getNodeLabel(const SDNode *Node,
138 const SelectionDAG *G) {
139 return DOTGraphTraits<SelectionDAG*>::getSimpleNodeLabel(Node, G);
140}
141
142
143/// viewGraph - Pop up a ghostview window with the reachable parts of the DAG
144/// rendered using 'dot'.
145///
146void SelectionDAG::viewGraph(const std::string &Title) {
147// This code is only for debugging!
148#ifndef NDEBUG
149 ViewGraph(this, "dag." + getMachineFunction().getName(),
150 false, Title);
151#else
152 errs() << "SelectionDAG::viewGraph is only available in debug builds on "
153 << "systems with Graphviz or gv!\n";
154#endif // NDEBUG
155}
156
157// This overload is defined out-of-line here instead of just using a
158// default parameter because this is easiest for gdb to call.
159void SelectionDAG::viewGraph() {
160 viewGraph(Title: "");
161}
162
163/// Just dump dot graph to a user-provided path and title.
164/// This doesn't open the dot viewer program and
165/// helps visualization when outside debugging session.
166/// FileName expects absolute path. If provided
167/// without any path separators then the file
168/// will be created in the current directory.
169/// Error will be emitted if the path is insane.
170#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
171LLVM_DUMP_METHOD void SelectionDAG::dumpDotGraph(const Twine &FileName,
172 const Twine &Title) {
173 dumpDotGraphToFile(this, FileName, Title);
174}
175#endif
176
177/// clearGraphAttrs - Clear all previously defined node graph attributes.
178/// Intended to be used from a debugging tool (eg. gdb).
179void SelectionDAG::clearGraphAttrs() {
180#if LLVM_ENABLE_ABI_BREAKING_CHECKS
181 NodeGraphAttrs.clear();
182#else
183 errs() << "SelectionDAG::clearGraphAttrs is only available in builds with "
184 << "ABI breaking checks enabled on systems with Graphviz or gv!\n";
185#endif
186}
187
188
189/// setGraphAttrs - Set graph attributes for a node. (eg. "color=red".)
190///
191void SelectionDAG::setGraphAttrs(const SDNode *N, const char *Attrs) {
192#if LLVM_ENABLE_ABI_BREAKING_CHECKS
193 NodeGraphAttrs[N] = Attrs;
194#else
195 errs() << "SelectionDAG::setGraphAttrs is only available in builds with "
196 << "ABI breaking checks enabled on systems with Graphviz or gv!\n";
197#endif
198}
199
200
201/// getGraphAttrs - Get graph attributes for a node. (eg. "color=red".)
202/// Used from getNodeAttributes.
203std::string SelectionDAG::getGraphAttrs(const SDNode *N) const {
204#if LLVM_ENABLE_ABI_BREAKING_CHECKS
205 std::map<const SDNode *, std::string>::const_iterator I =
206 NodeGraphAttrs.find(N);
207
208 if (I != NodeGraphAttrs.end())
209 return I->second;
210 else
211 return "";
212#else
213 errs() << "SelectionDAG::getGraphAttrs is only available in builds with "
214 << "ABI breaking checks enabled on systems with Graphviz or gv!\n";
215 return std::string();
216#endif
217}
218
219/// setGraphColor - Convenience for setting node color attribute.
220///
221void SelectionDAG::setGraphColor(const SDNode *N, const char *Color) {
222#if LLVM_ENABLE_ABI_BREAKING_CHECKS
223 NodeGraphAttrs[N] = std::string("color=") + Color;
224#else
225 errs() << "SelectionDAG::setGraphColor is only available in builds with "
226 << "ABI breaking checks enabled on systems with Graphviz or gv!\n";
227#endif
228}
229
230/// setSubgraphColorHelper - Implement setSubgraphColor. Return
231/// whether we truncated the search.
232///
233bool SelectionDAG::setSubgraphColorHelper(SDNode *N, const char *Color, DenseSet<SDNode *> &visited,
234 int level, bool &printed) {
235 bool hit_limit = false;
236
237#ifndef NDEBUG
238 if (level >= 20) {
239 if (!printed) {
240 printed = true;
241 LLVM_DEBUG(dbgs() << "setSubgraphColor hit max level\n");
242 }
243 return true;
244 }
245
246 unsigned oldSize = visited.size();
247 visited.insert(N);
248 if (visited.size() != oldSize) {
249 setGraphColor(N, Color);
250 for(SDNodeIterator i = SDNodeIterator::begin(N), iend = SDNodeIterator::end(N);
251 i != iend;
252 ++i) {
253 hit_limit = setSubgraphColorHelper(*i, Color, visited, level+1, printed) || hit_limit;
254 }
255 }
256#else
257 errs() << "SelectionDAG::setSubgraphColor is only available in debug builds"
258 << " on systems with Graphviz or gv!\n";
259#endif
260 return hit_limit;
261}
262
263/// setSubgraphColor - Convenience for setting subgraph color attribute.
264///
265void SelectionDAG::setSubgraphColor(SDNode *N, const char *Color) {
266#ifndef NDEBUG
267 DenseSet<SDNode *> visited;
268 bool printed = false;
269 if (setSubgraphColorHelper(N, Color, visited, 0, printed)) {
270 // Visually mark that we hit the limit
271 if (strcmp(Color, "red") == 0) {
272 setSubgraphColorHelper(N, "blue", visited, 0, printed);
273 } else if (strcmp(Color, "yellow") == 0) {
274 setSubgraphColorHelper(N, "green", visited, 0, printed);
275 }
276 }
277
278#else
279 errs() << "SelectionDAG::setSubgraphColor is only available in debug builds"
280 << " on systems with Graphviz or gv!\n";
281#endif
282}
283
284std::string ScheduleDAGSDNodes::getGraphNodeLabel(const SUnit *SU) const {
285 std::string s;
286 raw_string_ostream O(s);
287 O << "SU(" << SU->NodeNum << "): ";
288 if (SU->getNode()) {
289 SmallVector<SDNode *, 4> GluedNodes;
290 for (SDNode *N = SU->getNode(); N; N = N->getGluedNode())
291 GluedNodes.push_back(Elt: N);
292 while (!GluedNodes.empty()) {
293 O << DOTGraphTraits<SelectionDAG*>
294 ::getSimpleNodeLabel(Node: GluedNodes.back(), G: DAG);
295 GluedNodes.pop_back();
296 if (!GluedNodes.empty())
297 O << "\n ";
298 }
299 } else {
300 O << "CROSS RC COPY";
301 }
302 return s;
303}
304
305void ScheduleDAGSDNodes::getCustomGraphFeatures(GraphWriter<ScheduleDAG*> &GW) const {
306 if (DAG) {
307 // Draw a special "GraphRoot" node to indicate the root of the graph.
308 GW.emitSimpleNode(ID: nullptr, Attr: "plaintext=circle", Label: "GraphRoot");
309 const SDNode *N = DAG->getRoot().getNode();
310 if (N && N->getNodeId() != -1)
311 GW.emitEdge(SrcNodeID: nullptr, SrcNodePort: -1, DestNodeID: &SUnits[N->getNodeId()], DestNodePort: -1,
312 Attrs: "color=blue,style=dashed");
313 }
314}
315