1//===-- Analysis.cpp --------------------------------------------*- 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#include "Analysis.h"
10#include "BenchmarkResult.h"
11#include "llvm/ADT/STLExtras.h"
12#include "llvm/MC/MCAsmInfo.h"
13#include "llvm/MC/MCTargetOptions.h"
14#include "llvm/Support/FormatVariadic.h"
15#include <limits>
16#include <vector>
17
18namespace llvm {
19namespace exegesis {
20
21static const char kCsvSep = ',';
22
23namespace {
24
25enum EscapeTag { kEscapeCsv, kEscapeHtml, kEscapeHtmlString };
26
27template <EscapeTag Tag> void writeEscaped(raw_ostream &OS, const StringRef S);
28
29template <> void writeEscaped<kEscapeCsv>(raw_ostream &OS, const StringRef S) {
30 if (!S.contains(C: kCsvSep)) {
31 OS << S;
32 } else {
33 // Needs escaping.
34 OS << '"';
35 for (const char C : S) {
36 if (C == '"')
37 OS << "\"\"";
38 else
39 OS << C;
40 }
41 OS << '"';
42 }
43}
44
45template <> void writeEscaped<kEscapeHtml>(raw_ostream &OS, const 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
58template <>
59void writeEscaped<kEscapeHtmlString>(raw_ostream &OS, const StringRef S) {
60 for (const char C : S) {
61 if (C == '"')
62 OS << "\\\"";
63 else
64 OS << C;
65 }
66}
67
68} // namespace
69
70template <EscapeTag Tag>
71static void
72writeClusterId(raw_ostream &OS,
73 const BenchmarkClustering::ClusterId &CID) {
74 if (CID.isNoise())
75 writeEscaped<Tag>(OS, "[noise]");
76 else if (CID.isError())
77 writeEscaped<Tag>(OS, "[error]");
78 else
79 OS << CID.getId();
80}
81
82template <EscapeTag Tag>
83static void writeMeasurementValue(raw_ostream &OS, const double Value) {
84 // Given Value, if we wanted to serialize it to a string,
85 // how many base-10 digits will we need to store, max?
86 static constexpr auto MaxDigitCount =
87 std::numeric_limits<decltype(Value)>::max_digits10;
88 // Also, we will need a decimal separator.
89 static constexpr auto DecimalSeparatorLen = 1; // '.' e.g.
90 // So how long of a string will the serialization produce, max?
91 static constexpr auto SerializationLen = MaxDigitCount + DecimalSeparatorLen;
92
93 // WARNING: when changing the format, also adjust the small-size estimate ^.
94 static constexpr StringLiteral SimpleFloatFormat = StringLiteral("{0:F}");
95
96 writeEscaped<Tag>(
97 OS, formatv(Fmt: SimpleFloatFormat.data(), Vals: Value).sstr<SerializationLen>());
98}
99
100template <typename EscapeTag, EscapeTag Tag>
101void Analysis::writeSnippet(raw_ostream &OS, ArrayRef<uint8_t> Bytes,
102 const char *Separator) const {
103 SmallVector<std::string, 3> Lines;
104 // Parse the asm snippet and print it.
105 while (!Bytes.empty()) {
106 MCInst MI;
107 uint64_t MISize = 0;
108 if (!DisasmHelper_->decodeInst(MI, MISize, Bytes)) {
109 writeEscaped<Tag>(OS, join(R&: Lines, Separator));
110 writeEscaped<Tag>(OS, Separator);
111 writeEscaped<Tag>(OS, "[error decoding asm snippet]");
112 return;
113 }
114 SmallString<128> InstPrinterStr; // FIXME: magic number.
115 raw_svector_ostream OSS(InstPrinterStr);
116 DisasmHelper_->printInst(MI: &MI, OS&: OSS);
117 Bytes = Bytes.drop_front(N: MISize);
118 Lines.emplace_back(Args: InstPrinterStr.str().trim());
119 }
120 writeEscaped<Tag>(OS, join(R&: Lines, Separator));
121}
122
123// Prints a row representing an instruction, along with scheduling info and
124// point coordinates (measurements).
125void Analysis::printInstructionRowCsv(const size_t PointId,
126 raw_ostream &OS) const {
127 const Benchmark &Point = Clustering_.getPoints()[PointId];
128 writeClusterId<kEscapeCsv>(OS, CID: Clustering_.getClusterIdForPoint(P: PointId));
129 OS << kCsvSep;
130 writeSnippet<EscapeTag, kEscapeCsv>(OS, Bytes: Point.AssembledSnippet, Separator: "; ");
131 OS << kCsvSep;
132 writeEscaped<kEscapeCsv>(OS, S: Point.Key.Config);
133 OS << kCsvSep;
134 assert(!Point.Key.Instructions.empty());
135 const MCInst &MCI = Point.keyInstruction();
136 unsigned SchedClassId;
137 std::tie(args&: SchedClassId, args: std::ignore) = ResolvedSchedClass::resolveSchedClassId(
138 SubtargetInfo: State_.getSubtargetInfo(), InstrInfo: State_.getInstrInfo(), MCI);
139#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
140 const MCSchedClassDesc *const SCDesc =
141 State_.getSubtargetInfo().getSchedModel().getSchedClassDesc(SchedClassId);
142 writeEscaped<kEscapeCsv>(OS, SCDesc->Name);
143#else
144 OS << SchedClassId;
145#endif
146 for (const auto &Measurement : Point.Measurements) {
147 OS << kCsvSep;
148 writeMeasurementValue<kEscapeCsv>(OS, Value: Measurement.PerInstructionValue);
149 }
150 OS << "\n";
151}
152
153Analysis::Analysis(const LLVMState &State,
154 const BenchmarkClustering &Clustering,
155 double AnalysisInconsistencyEpsilon,
156 bool AnalysisDisplayUnstableOpcodes)
157 : Clustering_(Clustering), State_(State),
158 AnalysisInconsistencyEpsilonSquared_(AnalysisInconsistencyEpsilon *
159 AnalysisInconsistencyEpsilon),
160 AnalysisDisplayUnstableOpcodes_(AnalysisDisplayUnstableOpcodes) {
161 if (Clustering.getPoints().empty())
162 return;
163
164 DisasmHelper_ = std::make_unique<DisassemblerHelper>(args: State);
165}
166
167template <>
168Error Analysis::run<Analysis::PrintClusters>(raw_ostream &OS) const {
169 if (Clustering_.getPoints().empty())
170 return Error::success();
171
172 // Write the header.
173 OS << "cluster_id" << kCsvSep << "opcode_name" << kCsvSep << "config"
174 << kCsvSep << "sched_class";
175 for (const auto &Measurement : Clustering_.getPoints().front().Measurements) {
176 OS << kCsvSep;
177 writeEscaped<kEscapeCsv>(OS, S: Measurement.Key);
178 }
179 OS << "\n";
180
181 // Write the points.
182 for (const auto &ClusterIt : Clustering_.getValidClusters()) {
183 for (const size_t PointId : ClusterIt.PointIndices) {
184 printInstructionRowCsv(PointId, OS);
185 }
186 OS << "\n\n";
187 }
188 return Error::success();
189}
190
191Analysis::ResolvedSchedClassAndPoints::ResolvedSchedClassAndPoints(
192 ResolvedSchedClass &&RSC)
193 : RSC(std::move(RSC)) {}
194
195std::vector<Analysis::ResolvedSchedClassAndPoints>
196Analysis::makePointsPerSchedClass() const {
197 std::vector<ResolvedSchedClassAndPoints> Entries;
198 // Maps SchedClassIds to index in result.
199 std::unordered_map<unsigned, size_t> SchedClassIdToIndex;
200 const auto &Points = Clustering_.getPoints();
201 for (size_t PointId = 0, E = Points.size(); PointId < E; ++PointId) {
202 const Benchmark &Point = Points[PointId];
203 if (!Point.Error.empty())
204 continue;
205 assert(!Point.Key.Instructions.empty());
206 // FIXME: we should be using the tuple of classes for instructions in the
207 // snippet as key.
208 const MCInst &MCI = Point.keyInstruction();
209 unsigned SchedClassId;
210 bool WasVariant;
211 std::tie(args&: SchedClassId, args&: WasVariant) =
212 ResolvedSchedClass::resolveSchedClassId(SubtargetInfo: State_.getSubtargetInfo(),
213 InstrInfo: State_.getInstrInfo(), MCI);
214 const auto IndexIt = SchedClassIdToIndex.find(x: SchedClassId);
215 if (IndexIt == SchedClassIdToIndex.end()) {
216 // Create a new entry.
217 SchedClassIdToIndex.emplace(args&: SchedClassId, args: Entries.size());
218 ResolvedSchedClassAndPoints Entry(ResolvedSchedClass(
219 State_.getSubtargetInfo(), SchedClassId, WasVariant));
220 Entry.PointIds.push_back(x: PointId);
221 Entries.push_back(x: std::move(Entry));
222 } else {
223 // Append to the existing entry.
224 Entries[IndexIt->second].PointIds.push_back(x: PointId);
225 }
226 }
227 return Entries;
228}
229
230// Parallel benchmarks repeat the same opcode multiple times. Just show this
231// opcode and show the whole snippet only on hover.
232static void writeParallelSnippetHtml(raw_ostream &OS,
233 const std::vector<MCInst> &Instructions,
234 const MCInstrInfo &InstrInfo) {
235 if (Instructions.empty())
236 return;
237 writeEscaped<kEscapeHtml>(OS, S: InstrInfo.getName(Opcode: Instructions[0].getOpcode()));
238 if (Instructions.size() > 1)
239 OS << " (x" << Instructions.size() << ")";
240}
241
242// Latency tries to find a serial path. Just show the opcode path and show the
243// whole snippet only on hover.
244static void writeLatencySnippetHtml(raw_ostream &OS,
245 const std::vector<MCInst> &Instructions,
246 const MCInstrInfo &InstrInfo) {
247 bool First = true;
248 for (const MCInst &Instr : Instructions) {
249 if (First)
250 First = false;
251 else
252 OS << " &rarr; ";
253 writeEscaped<kEscapeHtml>(OS, S: InstrInfo.getName(Opcode: Instr.getOpcode()));
254 }
255}
256
257void Analysis::printPointHtml(const Benchmark &Point, raw_ostream &OS) const {
258 OS << "<li><span class=\"mono\" title=\"";
259 writeSnippet<EscapeTag, kEscapeHtmlString>(OS, Bytes: Point.AssembledSnippet, Separator: "\n");
260 OS << "\">";
261 switch (Point.Mode) {
262 case Benchmark::Latency:
263 writeLatencySnippetHtml(OS, Instructions: Point.Key.Instructions, InstrInfo: State_.getInstrInfo());
264 break;
265 case Benchmark::Uops:
266 case Benchmark::InverseThroughput:
267 writeParallelSnippetHtml(OS, Instructions: Point.Key.Instructions, InstrInfo: State_.getInstrInfo());
268 break;
269 default:
270 llvm_unreachable("invalid mode");
271 }
272 OS << "</span> <span class=\"mono\">";
273 writeEscaped<kEscapeHtml>(OS, S: Point.Key.Config);
274 OS << "</span></li>";
275}
276
277void Analysis::printSchedClassClustersHtml(
278 const std::vector<SchedClassCluster> &Clusters,
279 const ResolvedSchedClass &RSC, raw_ostream &OS) const {
280 const auto &Points = Clustering_.getPoints();
281 OS << "<table class=\"sched-class-clusters\">";
282 OS << "<tr><th>ClusterId</th><th>Opcode/Config</th>";
283 assert(!Clusters.empty());
284 for (const auto &Measurement :
285 Points[Clusters[0].getPointIds()[0]].Measurements) {
286 OS << "<th>";
287 writeEscaped<kEscapeHtml>(OS, S: Measurement.Key);
288 OS << "</th>";
289 }
290 OS << "</tr>";
291 for (const SchedClassCluster &Cluster : Clusters) {
292 OS << "<tr class=\""
293 << (Cluster.measurementsMatch(STI: State_.getSubtargetInfo(), SC: RSC,
294 Clustering: Clustering_,
295 AnalysisInconsistencyEpsilonSquared_)
296 ? "good-cluster"
297 : "bad-cluster")
298 << "\"><td>";
299 writeClusterId<kEscapeHtml>(OS, CID: Cluster.id());
300 OS << "</td><td><ul>";
301 for (const size_t PointId : Cluster.getPointIds()) {
302 printPointHtml(Point: Points[PointId], OS);
303 }
304 OS << "</ul></td>";
305 for (const auto &Stats : Cluster.getCentroid().getStats()) {
306 OS << "<td class=\"measurement\">";
307 writeMeasurementValue<kEscapeHtml>(OS, Value: Stats.avg());
308 OS << "<br><span class=\"minmax\">[";
309 writeMeasurementValue<kEscapeHtml>(OS, Value: Stats.min());
310 OS << ";";
311 writeMeasurementValue<kEscapeHtml>(OS, Value: Stats.max());
312 OS << "]</span></td>";
313 }
314 OS << "</tr>";
315 }
316 OS << "</table>";
317}
318
319void Analysis::SchedClassCluster::addPoint(
320 size_t PointId, const BenchmarkClustering &Clustering) {
321 PointIds.push_back(x: PointId);
322 const auto &Point = Clustering.getPoints()[PointId];
323 if (ClusterId.isUndef())
324 ClusterId = Clustering.getClusterIdForPoint(P: PointId);
325 assert(ClusterId == Clustering.getClusterIdForPoint(PointId));
326
327 Centroid.addPoint(Point: Point.Measurements);
328}
329
330bool Analysis::SchedClassCluster::measurementsMatch(
331 const MCSubtargetInfo &STI, const ResolvedSchedClass &RSC,
332 const BenchmarkClustering &Clustering,
333 const double AnalysisInconsistencyEpsilonSquared_) const {
334 assert(!Clustering.getPoints().empty());
335 const Benchmark::ModeE Mode = Clustering.getPoints()[0].Mode;
336
337 if (!Centroid.validate(Mode))
338 return false;
339
340 const std::vector<BenchmarkMeasure> ClusterCenterPoint =
341 Centroid.getAsPoint();
342
343 const std::vector<BenchmarkMeasure> SchedClassPoint =
344 RSC.getAsPoint(Mode, STI, Representative: Centroid.getStats());
345 if (SchedClassPoint.empty())
346 return false; // In Uops mode validate() may not be enough.
347
348 assert(ClusterCenterPoint.size() == SchedClassPoint.size() &&
349 "Expected measured/sched data dimensions to match.");
350
351 return Clustering.isNeighbour(P: ClusterCenterPoint, Q: SchedClassPoint,
352 EpsilonSquared_: AnalysisInconsistencyEpsilonSquared_);
353}
354
355void Analysis::printSchedClassDescHtml(const ResolvedSchedClass &RSC,
356 raw_ostream &OS) const {
357 OS << "<table class=\"sched-class-desc\">";
358 OS << "<tr><th>Valid</th><th>Variant</th><th>NumMicroOps</th><th>Latency</"
359 "th><th>RThroughput</th><th>WriteProcRes</th><th title=\"This is the "
360 "idealized unit resource (port) pressure assuming ideal "
361 "distribution\">Idealized Resource Pressure</th></tr>";
362 if (RSC.SCDesc->isValid()) {
363 const auto &SI = State_.getSubtargetInfo();
364 const auto &SM = SI.getSchedModel();
365 OS << "<tr><td>&#10004;</td>";
366 OS << "<td>" << (RSC.WasVariant ? "&#10004;" : "&#10005;") << "</td>";
367 OS << "<td>" << RSC.SCDesc->NumMicroOps << "</td>";
368 // Latencies.
369 OS << "<td><ul>";
370 for (int I = 0, E = RSC.SCDesc->NumWriteLatencyEntries; I < E; ++I) {
371 const auto *const Entry = SI.getWriteLatencyEntry(SC: RSC.SCDesc, DefIdx: I);
372 OS << "<li>" << Entry->Cycles;
373 if (RSC.SCDesc->NumWriteLatencyEntries > 1) {
374 // Dismabiguate if more than 1 latency.
375 OS << " (WriteResourceID " << Entry->WriteResourceID << ")";
376 }
377 OS << "</li>";
378 }
379 OS << "</ul></td>";
380 // inverse throughput.
381 OS << "<td>";
382 writeMeasurementValue<kEscapeHtml>(
383 OS, Value: MCSchedModel::getReciprocalThroughput(STI: SI, SCDesc: *RSC.SCDesc));
384 OS << "</td>";
385 // WriteProcRes.
386 OS << "<td><ul>";
387 for (const auto &WPR : RSC.NonRedundantWriteProcRes) {
388 OS << "<li><span class=\"mono\">";
389 writeEscaped<kEscapeHtml>(OS,
390 S: SM.getProcResource(ProcResourceIdx: WPR.ProcResourceIdx)->Name);
391 OS << "</span>: " << WPR.ReleaseAtCycle << "</li>";
392 }
393 OS << "</ul></td>";
394 // Idealized port pressure.
395 OS << "<td><ul>";
396 for (const auto &Pressure : RSC.IdealizedProcResPressure) {
397 OS << "<li><span class=\"mono\">";
398 writeEscaped<kEscapeHtml>(
399 OS, S: SI.getSchedModel().getProcResource(ProcResourceIdx: Pressure.first)->Name);
400 OS << "</span>: ";
401 writeMeasurementValue<kEscapeHtml>(OS, Value: Pressure.second);
402 OS << "</li>";
403 }
404 OS << "</ul></td>";
405 OS << "</tr>";
406 } else {
407 OS << "<tr><td>&#10005;</td><td></td><td></td></tr>";
408 }
409 OS << "</table>";
410}
411
412void Analysis::printClusterRawHtml(const BenchmarkClustering::ClusterId &Id,
413 StringRef display_name,
414 raw_ostream &OS) const {
415 const auto &Points = Clustering_.getPoints();
416 const auto &Cluster = Clustering_.getCluster(Id);
417 if (Cluster.PointIndices.empty())
418 return;
419
420 OS << "<div class=\"inconsistency\"><p>" << display_name << " Cluster ("
421 << Cluster.PointIndices.size() << " points)</p>";
422 OS << "<table class=\"sched-class-clusters\">";
423 // Table Header.
424 OS << "<tr><th>ClusterId</th><th>Opcode/Config</th>";
425 for (const auto &Measurement : Points[Cluster.PointIndices[0]].Measurements) {
426 OS << "<th>";
427 writeEscaped<kEscapeHtml>(OS, S: Measurement.Key);
428 OS << "</th>";
429 }
430 OS << "</tr>";
431
432 // Point data.
433 for (const auto &PointId : Cluster.PointIndices) {
434 OS << "<tr class=\"bad-cluster\"><td>" << display_name << "</td><td><ul>";
435 printPointHtml(Point: Points[PointId], OS);
436 OS << "</ul></td>";
437 for (const auto &Measurement : Points[PointId].Measurements) {
438 OS << "<td class=\"measurement\">";
439 writeMeasurementValue<kEscapeHtml>(OS, Value: Measurement.PerInstructionValue);
440 }
441 OS << "</tr>";
442 }
443 OS << "</table>";
444
445 OS << "</div>";
446
447} // namespace exegesis
448
449static constexpr const char kHtmlHead[] = R"(
450<head>
451<title>llvm-exegesis Analysis Results</title>
452<style>
453body {
454 font-family: sans-serif
455}
456span.sched-class-name {
457 font-weight: bold;
458 font-family: monospace;
459}
460span.opcode {
461 font-family: monospace;
462}
463span.config {
464 font-family: monospace;
465}
466div.inconsistency {
467 margin-top: 50px;
468}
469table {
470 margin-left: 50px;
471 border-collapse: collapse;
472}
473table, table tr,td,th {
474 border: 1px solid #444;
475}
476table ul {
477 padding-left: 0px;
478 margin: 0px;
479 list-style-type: none;
480}
481table.sched-class-clusters td {
482 padding-left: 10px;
483 padding-right: 10px;
484 padding-top: 10px;
485 padding-bottom: 10px;
486}
487table.sched-class-desc td {
488 padding-left: 10px;
489 padding-right: 10px;
490 padding-top: 2px;
491 padding-bottom: 2px;
492}
493span.mono {
494 font-family: monospace;
495}
496td.measurement {
497 text-align: center;
498}
499tr.good-cluster td.measurement {
500 color: #292
501}
502tr.bad-cluster td.measurement {
503 color: #922
504}
505tr.good-cluster td.measurement span.minmax {
506 color: #888;
507}
508tr.bad-cluster td.measurement span.minmax {
509 color: #888;
510}
511</style>
512</head>
513)";
514
515template <>
516Error Analysis::run<Analysis::PrintSchedClassInconsistencies>(
517 raw_ostream &OS) const {
518 const auto &FirstPoint = Clustering_.getPoints()[0];
519 // Print the header.
520 OS << "<!DOCTYPE html><html>" << kHtmlHead << "<body>";
521 OS << "<h1><span class=\"mono\">llvm-exegesis</span> Analysis Results</h1>";
522 OS << "<h3>Triple: <span class=\"mono\">";
523 writeEscaped<kEscapeHtml>(OS, S: FirstPoint.LLVMTriple);
524 OS << "</span></h3><h3>Cpu: <span class=\"mono\">";
525 writeEscaped<kEscapeHtml>(OS, S: FirstPoint.CpuName);
526 OS << "</span></h3>";
527 OS << "<h3>Epsilon: <span class=\"mono\">"
528 << format(Fmt: "%0.2f", Vals: std::sqrt(x: AnalysisInconsistencyEpsilonSquared_))
529 << "</span></h3>";
530
531 const auto &SI = State_.getSubtargetInfo();
532 for (const auto &RSCAndPoints : makePointsPerSchedClass()) {
533 if (!RSCAndPoints.RSC.SCDesc)
534 continue;
535 // Bucket sched class points into sched class clusters.
536 std::vector<SchedClassCluster> SchedClassClusters;
537 for (const size_t PointId : RSCAndPoints.PointIds) {
538 const auto &ClusterId = Clustering_.getClusterIdForPoint(P: PointId);
539 if (!ClusterId.isValid())
540 continue; // Ignore noise and errors. FIXME: take noise into account ?
541 if (ClusterId.isUnstable() ^ AnalysisDisplayUnstableOpcodes_)
542 continue; // Either display stable or unstable clusters only.
543 auto SchedClassClusterIt =
544 find_if(Range&: SchedClassClusters, P: [ClusterId](const SchedClassCluster &C) {
545 return C.id() == ClusterId;
546 });
547 if (SchedClassClusterIt == SchedClassClusters.end()) {
548 SchedClassClusters.emplace_back();
549 SchedClassClusterIt = std::prev(x: SchedClassClusters.end());
550 }
551 SchedClassClusterIt->addPoint(PointId, Clustering: Clustering_);
552 }
553
554 // Print any scheduling class that has at least one cluster that does not
555 // match the checked-in data.
556 if (all_of(Range&: SchedClassClusters, P: [this, &RSCAndPoints,
557 &SI](const SchedClassCluster &C) {
558 return C.measurementsMatch(STI: SI, RSC: RSCAndPoints.RSC, Clustering: Clustering_,
559 AnalysisInconsistencyEpsilonSquared_);
560 }))
561 continue; // Nothing weird.
562
563 OS << "<div class=\"inconsistency\"><p>Sched Class <span "
564 "class=\"sched-class-name\">";
565#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
566 writeEscaped<kEscapeHtml>(OS, RSCAndPoints.RSC.SCDesc->Name);
567#else
568 OS << RSCAndPoints.RSC.SchedClassId;
569#endif
570 OS << "</span> contains instructions whose performance characteristics do"
571 " not match that of LLVM:</p>";
572 printSchedClassClustersHtml(Clusters: SchedClassClusters, RSC: RSCAndPoints.RSC, OS);
573 OS << "<p>llvm SchedModel data:</p>";
574 printSchedClassDescHtml(RSC: RSCAndPoints.RSC, OS);
575 OS << "</div>";
576 }
577
578 printClusterRawHtml(Id: BenchmarkClustering::ClusterId::noise(),
579 display_name: "[noise]", OS);
580
581 OS << "</body></html>";
582 return Error::success();
583}
584
585} // namespace exegesis
586} // namespace llvm
587