xref: /llvm-project/llvm/tools/llvm-exegesis/lib/Analysis.cpp (revision 17d3c257b95ef14a21b9ecd5abb163aa8918dd09)
1 //===-- Analysis.cpp --------------------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "Analysis.h"
11 #include "BenchmarkResult.h"
12 #include "llvm/Support/FormatVariadic.h"
13 #include <unordered_set>
14 #include <vector>
15 
16 namespace exegesis {
17 
18 static const char kCsvSep = ',';
19 
20 namespace {
21 
22 enum EscapeTag { kEscapeCsv, kEscapeHtml };
23 
24 template <EscapeTag Tag>
25 void writeEscaped(llvm::raw_ostream &OS, const llvm::StringRef S);
26 
27 template <>
28 void writeEscaped<kEscapeCsv>(llvm::raw_ostream &OS, const llvm::StringRef S) {
29   if (std::find(S.begin(), S.end(), kCsvSep) == S.end()) {
30     OS << S;
31   } else {
32     // Needs escaping.
33     OS << '"';
34     for (const char C : S) {
35       if (C == '"')
36         OS << "\"\"";
37       else
38         OS << C;
39     }
40     OS << '"';
41   }
42 }
43 
44 template <>
45 void writeEscaped<kEscapeHtml>(llvm::raw_ostream &OS, const llvm::StringRef S) {
46   for (const char C : S) {
47     if (C == '<')
48       OS << "&lt;";
49     else if (C == '>')
50       OS << "&gt;";
51     else if (C == '&')
52       OS << "&amp;";
53     else
54       OS << C;
55   }
56 }
57 
58 } // namespace
59 
60 template <EscapeTag Tag>
61 static void
62 writeClusterId(llvm::raw_ostream &OS,
63                const InstructionBenchmarkClustering::ClusterId &CID) {
64   if (CID.isNoise())
65     writeEscaped<Tag>(OS, "[noise]");
66   else if (CID.isError())
67     writeEscaped<Tag>(OS, "[error]");
68   else
69     OS << CID.getId();
70 }
71 
72 template <EscapeTag Tag>
73 static void writeMeasurementValue(llvm::raw_ostream &OS, const double Value) {
74   writeEscaped<Tag>(OS, llvm::formatv("{0:F}", Value).str());
75 }
76 
77 // Prints a row representing an instruction, along with scheduling info and
78 // point coordinates (measurements).
79 void Analysis::printInstructionRowCsv(const size_t PointId,
80                                       llvm::raw_ostream &OS) const {
81   const InstructionBenchmark &Point = Clustering_.getPoints()[PointId];
82   writeClusterId<kEscapeCsv>(OS, Clustering_.getClusterIdForPoint(PointId));
83   OS << kCsvSep;
84   writeEscaped<kEscapeCsv>(OS, Point.Key.OpcodeName);
85   OS << kCsvSep;
86   writeEscaped<kEscapeCsv>(OS, Point.Key.Config);
87   OS << kCsvSep;
88   const auto OpcodeIt = MnemonicToOpcode_.find(Point.Key.OpcodeName);
89   if (OpcodeIt != MnemonicToOpcode_.end()) {
90     const unsigned SchedClassId =
91         InstrInfo_->get(OpcodeIt->second).getSchedClass();
92 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
93     const auto &SchedModel = SubtargetInfo_->getSchedModel();
94     const llvm::MCSchedClassDesc *const SCDesc =
95         SchedModel.getSchedClassDesc(SchedClassId);
96     writeEscaped<kEscapeCsv>(OS, SCDesc->Name);
97 #else
98     OS << SchedClassId;
99 #endif
100   }
101   // FIXME: Print the sched class once InstructionBenchmark separates key into
102   // (mnemonic, mode, opaque).
103   for (const auto &Measurement : Point.Measurements) {
104     OS << kCsvSep;
105     writeMeasurementValue<kEscapeCsv>(OS, Measurement.Value);
106   }
107   OS << "\n";
108 }
109 
110 Analysis::Analysis(const llvm::Target &Target,
111                    const InstructionBenchmarkClustering &Clustering)
112     : Clustering_(Clustering) {
113   if (Clustering.getPoints().empty())
114     return;
115 
116   InstrInfo_.reset(Target.createMCInstrInfo());
117   const InstructionBenchmark &FirstPoint = Clustering.getPoints().front();
118   SubtargetInfo_.reset(Target.createMCSubtargetInfo(FirstPoint.LLVMTriple,
119                                                     FirstPoint.CpuName, ""));
120 
121   // Build an index of mnemonic->opcode.
122   for (int I = 0, E = InstrInfo_->getNumOpcodes(); I < E; ++I)
123     MnemonicToOpcode_.emplace(InstrInfo_->getName(I), I);
124 }
125 
126 template <>
127 llvm::Error
128 Analysis::run<Analysis::PrintClusters>(llvm::raw_ostream &OS) const {
129   if (Clustering_.getPoints().empty())
130     return llvm::Error::success();
131 
132   // Write the header.
133   OS << "cluster_id" << kCsvSep << "opcode_name" << kCsvSep << "config"
134      << kCsvSep << "sched_class";
135   for (const auto &Measurement : Clustering_.getPoints().front().Measurements) {
136     OS << kCsvSep;
137     writeEscaped<kEscapeCsv>(OS, Measurement.Key);
138   }
139   OS << "\n";
140 
141   // Write the points.
142   const auto &Clusters = Clustering_.getValidClusters();
143   for (size_t I = 0, E = Clusters.size(); I < E; ++I) {
144     for (const size_t PointId : Clusters[I].PointIndices) {
145       printInstructionRowCsv(PointId, OS);
146     }
147     OS << "\n\n";
148   }
149   return llvm::Error::success();
150 }
151 
152 std::unordered_map<unsigned, std::vector<size_t>>
153 Analysis::makePointsPerSchedClass() const {
154   std::unordered_map<unsigned, std::vector<size_t>> PointsPerSchedClass;
155   const auto &Points = Clustering_.getPoints();
156   for (size_t PointId = 0, E = Points.size(); PointId < E; ++PointId) {
157     const InstructionBenchmark &Point = Points[PointId];
158     if (!Point.Error.empty())
159       continue;
160     const auto OpcodeIt = MnemonicToOpcode_.find(Point.Key.OpcodeName);
161     if (OpcodeIt == MnemonicToOpcode_.end())
162       continue;
163     const unsigned SchedClassId =
164         InstrInfo_->get(OpcodeIt->second).getSchedClass();
165     PointsPerSchedClass[SchedClassId].push_back(PointId);
166   }
167   return PointsPerSchedClass;
168 }
169 
170 void Analysis::printSchedClassHtml(std::vector<size_t> PointIds,
171                                    llvm::raw_ostream &OS) const {
172   assert(!PointIds.empty());
173   // Sort the points by cluster id so that we can display them grouped by
174   // cluster.
175   std::sort(PointIds.begin(), PointIds.end(),
176             [this](const size_t A, const size_t B) {
177               return Clustering_.getClusterIdForPoint(A) <
178                      Clustering_.getClusterIdForPoint(B);
179             });
180   const auto &Points = Clustering_.getPoints();
181   OS << "<table class=\"sched-class\">";
182   OS << "<tr><th>ClusterId</th><th>Opcode/Config</th>";
183   for (const auto &Measurement : Points[PointIds[0]].Measurements) {
184     OS << "<th>";
185     writeEscaped<kEscapeHtml>(OS, Measurement.Key);
186     OS << "</th>";
187   }
188   OS << "</tr>";
189   for (size_t I = 0, E = PointIds.size(); I < E;) {
190     const auto &CurrentClusterId =
191         Clustering_.getClusterIdForPoint(PointIds[I]);
192     OS << "<tr><td>";
193     writeClusterId<kEscapeHtml>(OS, CurrentClusterId);
194     OS << "</td><td><ul>";
195     const auto &ClusterRepresentative =
196         Points[PointIds[I]]; // FIXME: average measurements.
197     for (; I < E &&
198            Clustering_.getClusterIdForPoint(PointIds[I]) == CurrentClusterId;
199          ++I) {
200       OS << "<li><span class=\"mono\">";
201       writeEscaped<kEscapeHtml>(OS, Points[PointIds[I]].Key.OpcodeName);
202       OS << "</span> <span class=\"mono\">";
203       writeEscaped<kEscapeHtml>(OS, Points[PointIds[I]].Key.Config);
204       OS << "</span></li>";
205     }
206     OS << "</ul></td>";
207     for (const auto &Measurement : ClusterRepresentative.Measurements) {
208       OS << "<td>";
209       writeMeasurementValue<kEscapeHtml>(OS, Measurement.Value);
210       OS << "</td>";
211     }
212     OS << "</tr>";
213   }
214   OS << "</table>";
215 }
216 
217 static constexpr const char kHtmlHead[] = R"(
218 <head>
219 <title>llvm-exegesis Analysis Results</title>
220 <style>
221 body {
222   font-family: sans-serif
223 }
224 span.sched-class-name {
225   font-weight: bold;
226   font-family: monospace;
227 }
228 span.opcode {
229   font-family: monospace;
230 }
231 span.config {
232   font-family: monospace;
233 }
234 div.inconsistency {
235   margin-top: 50px;
236 }
237 table.sched-class {
238   margin-left: 50px;
239   border-collapse: collapse;
240 }
241 table.sched-class, table.sched-class tr,td,th {
242   border: 1px solid #444;
243 }
244 table.sched-class td {
245   padding-left: 10px;
246   padding-right: 10px;
247   padding-top: 10px;
248   padding-bottom: 10px;
249 }
250 table.sched-class ul {
251   padding-left: 0px;
252   margin: 0px;
253   list-style-type: none;
254 }
255 span.mono {
256   font-family: monospace;
257 }
258 </style>
259 </head>
260 )";
261 
262 template <>
263 llvm::Error Analysis::run<Analysis::PrintSchedClassInconsistencies>(
264     llvm::raw_ostream &OS) const {
265   // Print the header.
266   OS << "<!DOCTYPE html><html>" << kHtmlHead << "<body>";
267   OS << "<h1><span class=\"mono\">llvm-exegesis</span> Analysis Results</h1>";
268   OS << "<h3>Triple: <span class=\"mono\">";
269   writeEscaped<kEscapeHtml>(OS, Clustering_.getPoints()[0].LLVMTriple);
270   OS << "</span></h3><h3>Cpu: <span class=\"mono\">";
271   writeEscaped<kEscapeHtml>(OS, Clustering_.getPoints()[0].CpuName);
272   OS << "</span></h3>";
273 
274   // All the points in a scheduling class should be in the same cluster.
275   // Print any scheduling class for which this is not the case.
276   for (const auto &SchedClassAndPoints : makePointsPerSchedClass()) {
277     std::unordered_set<size_t> ClustersForSchedClass;
278     for (const size_t PointId : SchedClassAndPoints.second) {
279       const auto &ClusterId = Clustering_.getClusterIdForPoint(PointId);
280       if (!ClusterId.isValid())
281         continue; // Ignore noise and errors.
282       ClustersForSchedClass.insert(ClusterId.getId());
283     }
284     if (ClustersForSchedClass.size() <= 1)
285       continue; // Nothing weird.
286 
287     OS << "<div class=\"inconsistency\"><p>Sched Class <span "
288           "class=\"sched-class-name\">";
289 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
290     const auto &SchedModel = SubtargetInfo_->getSchedModel();
291     const llvm::MCSchedClassDesc *const SCDesc =
292         SchedModel.getSchedClassDesc(SchedClassAndPoints.first);
293     writeEscaped<kEscapeHtml>(OS, SCDesc->Name);
294 #else
295     OS << SchedClassAndPoints.first;
296 #endif
297     OS << "</span> contains instructions with distinct performance "
298           "characteristics, falling into "
299        << ClustersForSchedClass.size() << " clusters:</p>";
300     printSchedClassHtml(SchedClassAndPoints.second, OS);
301     OS << "</div>";
302   }
303 
304   OS << "</body></html>";
305   return llvm::Error::success();
306 }
307 
308 } // namespace exegesis
309