xref: /freebsd/contrib/llvm-project/llvm/tools/llvm-mca/llvm-mca.cpp (revision 700637cbb5e582861067a11aaca4d053546871d2)
1 //===-- llvm-mca.cpp - Machine Code Analyzer -------------------*- 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 utility is a simple driver that allows static performance analysis on
10 // machine code similarly to how IACA (Intel Architecture Code Analyzer) works.
11 //
12 //   llvm-mca [options] <file-name>
13 //      -march <type>
14 //      -mcpu <cpu>
15 //      -o <file>
16 //
17 // The target defaults to the host target.
18 // The cpu defaults to the 'native' host cpu.
19 // The output defaults to standard output.
20 //
21 //===----------------------------------------------------------------------===//
22 
23 #include "CodeRegion.h"
24 #include "CodeRegionGenerator.h"
25 #include "PipelinePrinter.h"
26 #include "Views/BottleneckAnalysis.h"
27 #include "Views/DispatchStatistics.h"
28 #include "Views/InstructionInfoView.h"
29 #include "Views/RegisterFileStatistics.h"
30 #include "Views/ResourcePressureView.h"
31 #include "Views/RetireControlUnitStatistics.h"
32 #include "Views/SchedulerStatistics.h"
33 #include "Views/SummaryView.h"
34 #include "Views/TimelineView.h"
35 #include "llvm/MC/MCAsmBackend.h"
36 #include "llvm/MC/MCAsmInfo.h"
37 #include "llvm/MC/MCCodeEmitter.h"
38 #include "llvm/MC/MCContext.h"
39 #include "llvm/MC/MCObjectFileInfo.h"
40 #include "llvm/MC/MCRegisterInfo.h"
41 #include "llvm/MC/MCSubtargetInfo.h"
42 #include "llvm/MC/MCTargetOptionsCommandFlags.h"
43 #include "llvm/MC/TargetRegistry.h"
44 #include "llvm/MCA/CodeEmitter.h"
45 #include "llvm/MCA/Context.h"
46 #include "llvm/MCA/CustomBehaviour.h"
47 #include "llvm/MCA/InstrBuilder.h"
48 #include "llvm/MCA/Pipeline.h"
49 #include "llvm/MCA/Stages/EntryStage.h"
50 #include "llvm/MCA/Stages/InstructionTables.h"
51 #include "llvm/MCA/Support.h"
52 #include "llvm/Support/CommandLine.h"
53 #include "llvm/Support/ErrorHandling.h"
54 #include "llvm/Support/ErrorOr.h"
55 #include "llvm/Support/FileSystem.h"
56 #include "llvm/Support/InitLLVM.h"
57 #include "llvm/Support/MemoryBuffer.h"
58 #include "llvm/Support/SourceMgr.h"
59 #include "llvm/Support/TargetSelect.h"
60 #include "llvm/Support/ToolOutputFile.h"
61 #include "llvm/Support/WithColor.h"
62 #include "llvm/TargetParser/Host.h"
63 
64 using namespace llvm;
65 
66 static mc::RegisterMCTargetOptionsFlags MOF;
67 
68 static cl::OptionCategory ToolOptions("Tool Options");
69 static cl::OptionCategory ViewOptions("View Options");
70 
71 static cl::opt<std::string> InputFilename(cl::Positional,
72                                           cl::desc("<input file>"),
73                                           cl::cat(ToolOptions), cl::init("-"));
74 
75 static cl::opt<std::string> OutputFilename("o", cl::desc("Output filename"),
76                                            cl::init("-"), cl::cat(ToolOptions),
77                                            cl::value_desc("filename"));
78 
79 static cl::opt<std::string>
80     ArchName("march",
81              cl::desc("Target architecture. "
82                       "See -version for available targets"),
83              cl::cat(ToolOptions));
84 
85 static cl::opt<std::string>
86     TripleName("mtriple",
87                cl::desc("Target triple. See -version for available targets"),
88                cl::cat(ToolOptions));
89 
90 static cl::opt<std::string>
91     MCPU("mcpu",
92          cl::desc("Target a specific cpu type (-mcpu=help for details)"),
93          cl::value_desc("cpu-name"), cl::cat(ToolOptions), cl::init("native"));
94 
95 static cl::list<std::string>
96     MATTRS("mattr", cl::CommaSeparated,
97            cl::desc("Target specific attributes (-mattr=help for details)"),
98            cl::value_desc("a1,+a2,-a3,..."), cl::cat(ToolOptions));
99 
100 static cl::opt<bool> PrintJson("json",
101                                cl::desc("Print the output in json format"),
102                                cl::cat(ToolOptions), cl::init(false));
103 
104 static cl::opt<int>
105     OutputAsmVariant("output-asm-variant",
106                      cl::desc("Syntax variant to use for output printing"),
107                      cl::cat(ToolOptions), cl::init(-1));
108 
109 static cl::opt<bool>
110     PrintImmHex("print-imm-hex", cl::cat(ToolOptions), cl::init(false),
111                 cl::desc("Prefer hex format when printing immediate values"));
112 
113 static cl::opt<unsigned> Iterations("iterations",
114                                     cl::desc("Number of iterations to run"),
115                                     cl::cat(ToolOptions), cl::init(0));
116 
117 static cl::opt<unsigned>
118     DispatchWidth("dispatch", cl::desc("Override the processor dispatch width"),
119                   cl::cat(ToolOptions), cl::init(0));
120 
121 static cl::opt<unsigned>
122     RegisterFileSize("register-file-size",
123                      cl::desc("Maximum number of physical registers which can "
124                               "be used for register mappings"),
125                      cl::cat(ToolOptions), cl::init(0));
126 
127 static cl::opt<unsigned>
128     MicroOpQueue("micro-op-queue-size", cl::Hidden,
129                  cl::desc("Number of entries in the micro-op queue"),
130                  cl::cat(ToolOptions), cl::init(0));
131 
132 static cl::opt<unsigned>
133     DecoderThroughput("decoder-throughput", cl::Hidden,
134                       cl::desc("Maximum throughput from the decoders "
135                                "(instructions per cycle)"),
136                       cl::cat(ToolOptions), cl::init(0));
137 
138 static cl::opt<unsigned>
139     CallLatency("call-latency", cl::Hidden,
140                 cl::desc("Number of cycles to assume for a call instruction"),
141                 cl::cat(ToolOptions), cl::init(100U));
142 
143 enum class SkipType { NONE, LACK_SCHED, PARSE_FAILURE, ANY_FAILURE };
144 
145 static cl::opt<enum SkipType> SkipUnsupportedInstructions(
146     "skip-unsupported-instructions",
147     cl::desc("Force analysis to continue in the presence of unsupported "
148              "instructions"),
149     cl::values(
150         clEnumValN(SkipType::NONE, "none",
151                    "Exit with an error when an instruction is unsupported for "
152                    "any reason (default)"),
153         clEnumValN(
154             SkipType::LACK_SCHED, "lack-sched",
155             "Skip instructions on input which lack scheduling information"),
156         clEnumValN(
157             SkipType::PARSE_FAILURE, "parse-failure",
158             "Skip lines on the input which fail to parse for any reason"),
159         clEnumValN(SkipType::ANY_FAILURE, "any",
160                    "Skip instructions or lines on input which are unsupported "
161                    "for any reason")),
162     cl::init(SkipType::NONE), cl::cat(ViewOptions));
163 
shouldSkip(enum SkipType skipType)164 bool shouldSkip(enum SkipType skipType) {
165   if (SkipUnsupportedInstructions == SkipType::NONE)
166     return false;
167   if (SkipUnsupportedInstructions == SkipType::ANY_FAILURE)
168     return true;
169   return skipType == SkipUnsupportedInstructions;
170 }
171 
172 static cl::opt<bool>
173     PrintRegisterFileStats("register-file-stats",
174                            cl::desc("Print register file statistics"),
175                            cl::cat(ViewOptions), cl::init(false));
176 
177 static cl::opt<bool> PrintDispatchStats("dispatch-stats",
178                                         cl::desc("Print dispatch statistics"),
179                                         cl::cat(ViewOptions), cl::init(false));
180 
181 static cl::opt<bool>
182     PrintSummaryView("summary-view", cl::Hidden,
183                      cl::desc("Print summary view (enabled by default)"),
184                      cl::cat(ViewOptions), cl::init(true));
185 
186 static cl::opt<bool> PrintSchedulerStats("scheduler-stats",
187                                          cl::desc("Print scheduler statistics"),
188                                          cl::cat(ViewOptions), cl::init(false));
189 
190 static cl::opt<bool>
191     PrintRetireStats("retire-stats",
192                      cl::desc("Print retire control unit statistics"),
193                      cl::cat(ViewOptions), cl::init(false));
194 
195 static cl::opt<bool> PrintResourcePressureView(
196     "resource-pressure",
197     cl::desc("Print the resource pressure view (enabled by default)"),
198     cl::cat(ViewOptions), cl::init(true));
199 
200 static cl::opt<bool> PrintTimelineView("timeline",
201                                        cl::desc("Print the timeline view"),
202                                        cl::cat(ViewOptions), cl::init(false));
203 
204 static cl::opt<unsigned> TimelineMaxIterations(
205     "timeline-max-iterations",
206     cl::desc("Maximum number of iterations to print in timeline view"),
207     cl::cat(ViewOptions), cl::init(0));
208 
209 static cl::opt<unsigned>
210     TimelineMaxCycles("timeline-max-cycles",
211                       cl::desc("Maximum number of cycles in the timeline view, "
212                                "or 0 for unlimited. Defaults to 80 cycles"),
213                       cl::cat(ViewOptions), cl::init(80));
214 
215 static cl::opt<bool>
216     AssumeNoAlias("noalias",
217                   cl::desc("If set, assume that loads and stores do not alias"),
218                   cl::cat(ToolOptions), cl::init(true));
219 
220 static cl::opt<unsigned> LoadQueueSize("lqueue",
221                                        cl::desc("Size of the load queue"),
222                                        cl::cat(ToolOptions), cl::init(0));
223 
224 static cl::opt<unsigned> StoreQueueSize("squeue",
225                                         cl::desc("Size of the store queue"),
226                                         cl::cat(ToolOptions), cl::init(0));
227 
228 enum class InstructionTablesType { NONE, NORMAL, FULL };
229 
230 static cl::opt<enum InstructionTablesType> InstructionTablesOption(
231     "instruction-tables", cl::desc("Print instruction tables"),
232     cl::values(clEnumValN(InstructionTablesType::NONE, "none",
233                           "Do not print instruction tables"),
234                clEnumValN(InstructionTablesType::NORMAL, "normal",
235                           "Print instruction tables"),
236                clEnumValN(InstructionTablesType::NORMAL, "", ""),
237                clEnumValN(InstructionTablesType::FULL, "full",
238                           "Print instruction tables with additional"
239                           " information: bypass latency, LLVM opcode,"
240                           " used resources")),
241     cl::cat(ToolOptions), cl::init(InstructionTablesType::NONE),
242     cl::ValueOptional);
243 
shouldPrintInstructionTables(enum InstructionTablesType ITType)244 static bool shouldPrintInstructionTables(enum InstructionTablesType ITType) {
245   return InstructionTablesOption == ITType;
246 }
247 
shouldPrintInstructionTables()248 static bool shouldPrintInstructionTables() {
249   return !shouldPrintInstructionTables(InstructionTablesType::NONE);
250 }
251 
252 static cl::opt<bool> PrintInstructionInfoView(
253     "instruction-info",
254     cl::desc("Print the instruction info view (enabled by default)"),
255     cl::cat(ViewOptions), cl::init(true));
256 
257 static cl::opt<bool> EnableAllStats("all-stats",
258                                     cl::desc("Print all hardware statistics"),
259                                     cl::cat(ViewOptions), cl::init(false));
260 
261 static cl::opt<bool>
262     EnableAllViews("all-views",
263                    cl::desc("Print all views including hardware statistics"),
264                    cl::cat(ViewOptions), cl::init(false));
265 
266 static cl::opt<bool> EnableBottleneckAnalysis(
267     "bottleneck-analysis",
268     cl::desc("Enable bottleneck analysis (disabled by default)"),
269     cl::cat(ViewOptions), cl::init(false));
270 
271 static cl::opt<bool> ShowEncoding(
272     "show-encoding",
273     cl::desc("Print encoding information in the instruction info view"),
274     cl::cat(ViewOptions), cl::init(false));
275 
276 static cl::opt<bool> ShowBarriers(
277     "show-barriers",
278     cl::desc("Print memory barrier information in the instruction info view"),
279     cl::cat(ViewOptions), cl::init(false));
280 
281 static cl::opt<bool> DisableCustomBehaviour(
282     "disable-cb",
283     cl::desc(
284         "Disable custom behaviour (use the default class which does nothing)."),
285     cl::cat(ViewOptions), cl::init(false));
286 
287 static cl::opt<bool> DisableInstrumentManager(
288     "disable-im",
289     cl::desc("Disable instrumentation manager (use the default class which "
290              "ignores instruments.)."),
291     cl::cat(ViewOptions), cl::init(false));
292 
293 namespace {
294 
getTarget(const char * ProgName)295 const Target *getTarget(const char *ProgName) {
296   if (TripleName.empty())
297     TripleName = Triple::normalize(sys::getDefaultTargetTriple());
298   Triple TheTriple(TripleName);
299 
300   // Get the target specific parser.
301   std::string Error;
302   const Target *TheTarget =
303       TargetRegistry::lookupTarget(ArchName, TheTriple, Error);
304   if (!TheTarget) {
305     errs() << ProgName << ": " << Error;
306     return nullptr;
307   }
308 
309   // Update TripleName with the updated triple from the target lookup.
310   TripleName = TheTriple.str();
311 
312   // Return the found target.
313   return TheTarget;
314 }
315 
getOutputStream()316 ErrorOr<std::unique_ptr<ToolOutputFile>> getOutputStream() {
317   if (OutputFilename == "")
318     OutputFilename = "-";
319   std::error_code EC;
320   auto Out = std::make_unique<ToolOutputFile>(OutputFilename, EC,
321                                               sys::fs::OF_TextWithCRLF);
322   if (!EC)
323     return std::move(Out);
324   return EC;
325 }
326 } // end of anonymous namespace
327 
processOptionImpl(cl::opt<bool> & O,const cl::opt<bool> & Default)328 static void processOptionImpl(cl::opt<bool> &O, const cl::opt<bool> &Default) {
329   if (!O.getNumOccurrences() || O.getPosition() < Default.getPosition())
330     O = Default.getValue();
331 }
332 
processViewOptions(bool IsOutOfOrder)333 static void processViewOptions(bool IsOutOfOrder) {
334   if (!EnableAllViews.getNumOccurrences() &&
335       !EnableAllStats.getNumOccurrences())
336     return;
337 
338   if (EnableAllViews.getNumOccurrences()) {
339     processOptionImpl(PrintSummaryView, EnableAllViews);
340     if (IsOutOfOrder)
341       processOptionImpl(EnableBottleneckAnalysis, EnableAllViews);
342     processOptionImpl(PrintResourcePressureView, EnableAllViews);
343     processOptionImpl(PrintTimelineView, EnableAllViews);
344     processOptionImpl(PrintInstructionInfoView, EnableAllViews);
345   }
346 
347   const cl::opt<bool> &Default =
348       EnableAllViews.getPosition() < EnableAllStats.getPosition()
349           ? EnableAllStats
350           : EnableAllViews;
351   processOptionImpl(PrintRegisterFileStats, Default);
352   processOptionImpl(PrintDispatchStats, Default);
353   processOptionImpl(PrintSchedulerStats, Default);
354   if (IsOutOfOrder)
355     processOptionImpl(PrintRetireStats, Default);
356 }
357 
358 // Returns true on success.
runPipeline(mca::Pipeline & P)359 static bool runPipeline(mca::Pipeline &P) {
360   // Handle pipeline errors here.
361   Expected<unsigned> Cycles = P.run();
362   if (!Cycles) {
363     WithColor::error() << toString(Cycles.takeError());
364     return false;
365   }
366   return true;
367 }
368 
main(int argc,char ** argv)369 int main(int argc, char **argv) {
370   InitLLVM X(argc, argv);
371 
372   // Initialize targets and assembly parsers.
373   InitializeAllTargetInfos();
374   InitializeAllTargetMCs();
375   InitializeAllAsmParsers();
376   InitializeAllTargetMCAs();
377 
378   // Register the Target and CPU printer for --version.
379   cl::AddExtraVersionPrinter(sys::printDefaultTargetAndDetectedCPU);
380 
381   // Enable printing of available targets when flag --version is specified.
382   cl::AddExtraVersionPrinter(TargetRegistry::printRegisteredTargetsForVersion);
383 
384   cl::HideUnrelatedOptions({&ToolOptions, &ViewOptions});
385 
386   // Parse flags and initialize target options.
387   cl::ParseCommandLineOptions(argc, argv,
388                               "llvm machine code performance analyzer.\n");
389 
390   // Get the target from the triple. If a triple is not specified, then select
391   // the default triple for the host. If the triple doesn't correspond to any
392   // registered target, then exit with an error message.
393   const char *ProgName = argv[0];
394   const Target *TheTarget = getTarget(ProgName);
395   if (!TheTarget)
396     return 1;
397 
398   // GetTarget() may replaced TripleName with a default triple.
399   // For safety, reconstruct the Triple object.
400   Triple TheTriple(TripleName);
401 
402   ErrorOr<std::unique_ptr<MemoryBuffer>> BufferPtr =
403       MemoryBuffer::getFileOrSTDIN(InputFilename);
404   if (std::error_code EC = BufferPtr.getError()) {
405     WithColor::error() << InputFilename << ": " << EC.message() << '\n';
406     return 1;
407   }
408 
409   if (MCPU == "native")
410     MCPU = std::string(llvm::sys::getHostCPUName());
411 
412   // Package up features to be passed to target/subtarget
413   std::string FeaturesStr;
414   if (MATTRS.size()) {
415     SubtargetFeatures Features;
416     for (std::string &MAttr : MATTRS)
417       Features.AddFeature(MAttr);
418     FeaturesStr = Features.getString();
419   }
420 
421   std::unique_ptr<MCSubtargetInfo> STI(
422       TheTarget->createMCSubtargetInfo(TripleName, MCPU, FeaturesStr));
423   assert(STI && "Unable to create subtarget info!");
424   if (!STI->isCPUStringValid(MCPU))
425     return 1;
426 
427   if (!STI->getSchedModel().hasInstrSchedModel()) {
428     WithColor::error()
429         << "unable to find instruction-level scheduling information for"
430         << " target triple '" << TheTriple.normalize() << "' and cpu '" << MCPU
431         << "'.\n";
432 
433     if (STI->getSchedModel().InstrItineraries)
434       WithColor::note()
435           << "cpu '" << MCPU << "' provides itineraries. However, "
436           << "instruction itineraries are currently unsupported.\n";
437     return 1;
438   }
439 
440   // Apply overrides to llvm-mca specific options.
441   bool IsOutOfOrder = STI->getSchedModel().isOutOfOrder();
442   processViewOptions(IsOutOfOrder);
443 
444   std::unique_ptr<MCRegisterInfo> MRI(TheTarget->createMCRegInfo(TripleName));
445   assert(MRI && "Unable to create target register info!");
446 
447   MCTargetOptions MCOptions = mc::InitMCTargetOptionsFromFlags();
448   std::unique_ptr<MCAsmInfo> MAI(
449       TheTarget->createMCAsmInfo(*MRI, TripleName, MCOptions));
450   assert(MAI && "Unable to create target asm info!");
451 
452   SourceMgr SrcMgr;
453 
454   // Tell SrcMgr about this buffer, which is what the parser will pick up.
455   SrcMgr.AddNewSourceBuffer(std::move(*BufferPtr), SMLoc());
456 
457   std::unique_ptr<MCInstrInfo> MCII(TheTarget->createMCInstrInfo());
458   assert(MCII && "Unable to create instruction info!");
459 
460   std::unique_ptr<MCInstrAnalysis> MCIA(
461       TheTarget->createMCInstrAnalysis(MCII.get()));
462 
463   // Need to initialize an MCInstPrinter as it is
464   // required for initializing the MCTargetStreamer
465   // which needs to happen within the CRG.parseAnalysisRegions() call below.
466   // Without an MCTargetStreamer, certain assembly directives can trigger a
467   // segfault. (For example, the .cv_fpo_proc directive on x86 will segfault if
468   // we don't initialize the MCTargetStreamer.)
469   unsigned IPtempOutputAsmVariant =
470       OutputAsmVariant == -1 ? 0 : OutputAsmVariant;
471   std::unique_ptr<MCInstPrinter> IPtemp(TheTarget->createMCInstPrinter(
472       Triple(TripleName), IPtempOutputAsmVariant, *MAI, *MCII, *MRI));
473   if (!IPtemp) {
474     WithColor::error()
475         << "unable to create instruction printer for target triple '"
476         << TheTriple.normalize() << "' with assembly variant "
477         << IPtempOutputAsmVariant << ".\n";
478     return 1;
479   }
480 
481   // Parse the input and create CodeRegions that llvm-mca can analyze.
482   MCContext ACtx(TheTriple, MAI.get(), MRI.get(), STI.get(), &SrcMgr);
483   std::unique_ptr<MCObjectFileInfo> AMOFI(
484       TheTarget->createMCObjectFileInfo(ACtx, /*PIC=*/false));
485   ACtx.setObjectFileInfo(AMOFI.get());
486   mca::AsmAnalysisRegionGenerator CRG(*TheTarget, SrcMgr, ACtx, *MAI, *STI,
487                                       *MCII);
488   Expected<const mca::AnalysisRegions &> RegionsOrErr =
489       CRG.parseAnalysisRegions(std::move(IPtemp),
490                                shouldSkip(SkipType::PARSE_FAILURE));
491   if (!RegionsOrErr) {
492     if (auto Err =
493             handleErrors(RegionsOrErr.takeError(), [](const StringError &E) {
494               WithColor::error() << E.getMessage() << '\n';
495             })) {
496       // Default case.
497       WithColor::error() << toString(std::move(Err)) << '\n';
498     }
499     return 1;
500   }
501   const mca::AnalysisRegions &Regions = *RegionsOrErr;
502 
503   // Early exit if errors were found by the code region parsing logic.
504   if (!Regions.isValid())
505     return 1;
506 
507   if (Regions.empty()) {
508     WithColor::error() << "no assembly instructions found.\n";
509     return 1;
510   }
511 
512   std::unique_ptr<mca::InstrumentManager> IM;
513   if (!DisableInstrumentManager) {
514     IM = std::unique_ptr<mca::InstrumentManager>(
515         TheTarget->createInstrumentManager(*STI, *MCII));
516   }
517   if (!IM) {
518     // If the target doesn't have its own IM implemented (or the -disable-cb
519     // flag is set) then we use the base class (which does nothing).
520     IM = std::make_unique<mca::InstrumentManager>(*STI, *MCII);
521   }
522 
523   // Parse the input and create InstrumentRegion that llvm-mca
524   // can use to improve analysis.
525   MCContext ICtx(TheTriple, MAI.get(), MRI.get(), STI.get(), &SrcMgr);
526   std::unique_ptr<MCObjectFileInfo> IMOFI(
527       TheTarget->createMCObjectFileInfo(ICtx, /*PIC=*/false));
528   ICtx.setObjectFileInfo(IMOFI.get());
529   mca::AsmInstrumentRegionGenerator IRG(*TheTarget, SrcMgr, ICtx, *MAI, *STI,
530                                         *MCII, *IM);
531   Expected<const mca::InstrumentRegions &> InstrumentRegionsOrErr =
532       IRG.parseInstrumentRegions(std::move(IPtemp),
533                                  shouldSkip(SkipType::PARSE_FAILURE));
534   if (!InstrumentRegionsOrErr) {
535     if (auto Err = handleErrors(InstrumentRegionsOrErr.takeError(),
536                                 [](const StringError &E) {
537                                   WithColor::error() << E.getMessage() << '\n';
538                                 })) {
539       // Default case.
540       WithColor::error() << toString(std::move(Err)) << '\n';
541     }
542     return 1;
543   }
544   const mca::InstrumentRegions &InstrumentRegions = *InstrumentRegionsOrErr;
545 
546   // Early exit if errors were found by the instrumentation parsing logic.
547   if (!InstrumentRegions.isValid())
548     return 1;
549 
550   // Now initialize the output file.
551   auto OF = getOutputStream();
552   if (std::error_code EC = OF.getError()) {
553     WithColor::error() << EC.message() << '\n';
554     return 1;
555   }
556 
557   unsigned AssemblerDialect = CRG.getAssemblerDialect();
558   if (OutputAsmVariant >= 0)
559     AssemblerDialect = static_cast<unsigned>(OutputAsmVariant);
560   std::unique_ptr<MCInstPrinter> IP(TheTarget->createMCInstPrinter(
561       Triple(TripleName), AssemblerDialect, *MAI, *MCII, *MRI));
562   if (!IP) {
563     WithColor::error()
564         << "unable to create instruction printer for target triple '"
565         << TheTriple.normalize() << "' with assembly variant "
566         << AssemblerDialect << ".\n";
567     return 1;
568   }
569 
570   // Set the display preference for hex vs. decimal immediates.
571   IP->setPrintImmHex(PrintImmHex);
572 
573   std::unique_ptr<ToolOutputFile> TOF = std::move(*OF);
574 
575   const MCSchedModel &SM = STI->getSchedModel();
576 
577   std::unique_ptr<mca::InstrPostProcess> IPP;
578   if (!DisableCustomBehaviour) {
579     // TODO: It may be a good idea to separate CB and IPP so that they can
580     // be used independently of each other. What I mean by this is to add
581     // an extra command-line arg --disable-ipp so that CB and IPP can be
582     // toggled without needing to toggle both of them together.
583     IPP = std::unique_ptr<mca::InstrPostProcess>(
584         TheTarget->createInstrPostProcess(*STI, *MCII));
585   }
586   if (!IPP) {
587     // If the target doesn't have its own IPP implemented (or the -disable-cb
588     // flag is set) then we use the base class (which does nothing).
589     IPP = std::make_unique<mca::InstrPostProcess>(*STI, *MCII);
590   }
591 
592   // Create an instruction builder.
593   mca::InstrBuilder IB(*STI, *MCII, *MRI, MCIA.get(), *IM, CallLatency);
594 
595   // Create a context to control ownership of the pipeline hardware.
596   mca::Context MCA(*MRI, *STI);
597 
598   mca::PipelineOptions PO(MicroOpQueue, DecoderThroughput, DispatchWidth,
599                           RegisterFileSize, LoadQueueSize, StoreQueueSize,
600                           AssumeNoAlias, EnableBottleneckAnalysis);
601 
602   // Number each region in the sequence.
603   unsigned RegionIdx = 0;
604 
605   std::unique_ptr<MCCodeEmitter> MCE(
606       TheTarget->createMCCodeEmitter(*MCII, ACtx));
607   assert(MCE && "Unable to create code emitter!");
608 
609   std::unique_ptr<MCAsmBackend> MAB(TheTarget->createMCAsmBackend(
610       *STI, *MRI, mc::InitMCTargetOptionsFromFlags()));
611   assert(MAB && "Unable to create asm backend!");
612 
613   json::Object JSONOutput;
614   int NonEmptyRegions = 0;
615   for (const std::unique_ptr<mca::AnalysisRegion> &Region : Regions) {
616     // Skip empty code regions.
617     if (Region->empty())
618       continue;
619 
620     IB.clear();
621 
622     // Lower the MCInst sequence into an mca::Instruction sequence.
623     ArrayRef<MCInst> Insts = Region->getInstructions();
624     mca::CodeEmitter CE(*STI, *MAB, *MCE, Insts);
625 
626     IPP->resetState();
627 
628     DenseMap<const MCInst *, SmallVector<mca::Instrument *>> InstToInstruments;
629     SmallVector<std::unique_ptr<mca::Instruction>> LoweredSequence;
630     SmallPtrSet<const MCInst *, 16> DroppedInsts;
631     for (const MCInst &MCI : Insts) {
632       SMLoc Loc = MCI.getLoc();
633       const SmallVector<mca::Instrument *> Instruments =
634           InstrumentRegions.getActiveInstruments(Loc);
635 
636       Expected<std::unique_ptr<mca::Instruction>> Inst =
637           IB.createInstruction(MCI, Instruments);
638       if (!Inst) {
639         if (auto NewE = handleErrors(
640                 Inst.takeError(),
641                 [&IP, &STI](const mca::InstructionError<MCInst> &IE) {
642                   std::string InstructionStr;
643                   raw_string_ostream SS(InstructionStr);
644                   if (shouldSkip(SkipType::LACK_SCHED))
645                     WithColor::warning()
646                         << IE.Message
647                         << ", skipping with -skip-unsupported-instructions, "
648                            "note accuracy will be impacted:\n";
649                   else
650                     WithColor::error()
651                         << IE.Message
652                         << ", use -skip-unsupported-instructions=lack-sched to "
653                            "ignore these on the input.\n";
654                   IP->printInst(&IE.Inst, 0, "", *STI, SS);
655                   SS.flush();
656                   WithColor::note()
657                       << "instruction: " << InstructionStr << '\n';
658                 })) {
659           // Default case.
660           WithColor::error() << toString(std::move(NewE));
661         }
662         if (shouldSkip(SkipType::LACK_SCHED)) {
663           DroppedInsts.insert(&MCI);
664           continue;
665         }
666         return 1;
667       }
668 
669       IPP->postProcessInstruction(Inst.get(), MCI);
670       InstToInstruments.insert({&MCI, Instruments});
671       LoweredSequence.emplace_back(std::move(Inst.get()));
672     }
673 
674     Insts = Region->dropInstructions(DroppedInsts);
675 
676     // Skip empty regions.
677     if (Insts.empty())
678       continue;
679     NonEmptyRegions++;
680 
681     mca::CircularSourceMgr S(LoweredSequence,
682                              shouldPrintInstructionTables() ? 1 : Iterations);
683 
684     if (shouldPrintInstructionTables()) {
685       //  Create a pipeline, stages, and a printer.
686       auto P = std::make_unique<mca::Pipeline>();
687       P->appendStage(std::make_unique<mca::EntryStage>(S));
688       P->appendStage(std::make_unique<mca::InstructionTables>(SM));
689 
690       mca::PipelinePrinter Printer(*P, *Region, RegionIdx, *STI, PO);
691       if (PrintJson) {
692         Printer.addView(
693             std::make_unique<mca::InstructionView>(*STI, *IP, Insts));
694       }
695 
696       // Create the views for this pipeline, execute, and emit a report.
697       if (PrintInstructionInfoView) {
698         Printer.addView(std::make_unique<mca::InstructionInfoView>(
699             *STI, *MCII, CE, ShowEncoding, Insts, *IP, LoweredSequence,
700             ShowBarriers,
701             shouldPrintInstructionTables(InstructionTablesType::FULL), *IM,
702             InstToInstruments));
703       }
704 
705       if (PrintResourcePressureView)
706         Printer.addView(
707             std::make_unique<mca::ResourcePressureView>(*STI, *IP, Insts));
708 
709       if (!runPipeline(*P))
710         return 1;
711 
712       if (PrintJson) {
713         Printer.printReport(JSONOutput);
714       } else {
715         Printer.printReport(TOF->os());
716       }
717 
718       ++RegionIdx;
719       continue;
720     }
721 
722     // Create the CustomBehaviour object for enforcing Target Specific
723     // behaviours and dependencies that aren't expressed well enough
724     // in the tablegen. CB cannot depend on the list of MCInst or
725     // the source code (but it can depend on the list of
726     // mca::Instruction or any objects that can be reconstructed
727     // from the target information).
728     std::unique_ptr<mca::CustomBehaviour> CB;
729     if (!DisableCustomBehaviour)
730       CB = std::unique_ptr<mca::CustomBehaviour>(
731           TheTarget->createCustomBehaviour(*STI, S, *MCII));
732     if (!CB)
733       // If the target doesn't have its own CB implemented (or the -disable-cb
734       // flag is set) then we use the base class (which does nothing).
735       CB = std::make_unique<mca::CustomBehaviour>(*STI, S, *MCII);
736 
737     // Create a basic pipeline simulating an out-of-order backend.
738     auto P = MCA.createDefaultPipeline(PO, S, *CB);
739 
740     mca::PipelinePrinter Printer(*P, *Region, RegionIdx, *STI, PO);
741 
742     // Targets can define their own custom Views that exist within their
743     // /lib/Target/ directory so that the View can utilize their CustomBehaviour
744     // or other backend symbols / functionality that are not already exposed
745     // through one of the MC-layer classes. These Views will be initialized
746     // using the CustomBehaviour::getViews() variants.
747     // If a target makes a custom View that does not depend on their target
748     // CB or their backend, they should put the View within
749     // /tools/llvm-mca/Views/ instead.
750     if (!DisableCustomBehaviour) {
751       std::vector<std::unique_ptr<mca::View>> CBViews =
752           CB->getStartViews(*IP, Insts);
753       for (auto &CBView : CBViews)
754         Printer.addView(std::move(CBView));
755     }
756 
757     // When we output JSON, we add a view that contains the instructions
758     // and CPU resource information.
759     if (PrintJson) {
760       auto IV = std::make_unique<mca::InstructionView>(*STI, *IP, Insts);
761       Printer.addView(std::move(IV));
762     }
763 
764     if (PrintSummaryView)
765       Printer.addView(
766           std::make_unique<mca::SummaryView>(SM, Insts, DispatchWidth));
767 
768     if (EnableBottleneckAnalysis) {
769       if (!IsOutOfOrder) {
770         WithColor::warning()
771             << "bottleneck analysis is not supported for in-order CPU '" << MCPU
772             << "'.\n";
773       }
774       Printer.addView(std::make_unique<mca::BottleneckAnalysis>(
775           *STI, *IP, Insts, S.getNumIterations()));
776     }
777 
778     if (PrintInstructionInfoView)
779       Printer.addView(std::make_unique<mca::InstructionInfoView>(
780           *STI, *MCII, CE, ShowEncoding, Insts, *IP, LoweredSequence,
781           ShowBarriers, /*ShouldPrintFullInfo=*/false, *IM, InstToInstruments));
782 
783     // Fetch custom Views that are to be placed after the InstructionInfoView.
784     // Refer to the comment paired with the CB->getStartViews(*IP, Insts); line
785     // for more info.
786     if (!DisableCustomBehaviour) {
787       std::vector<std::unique_ptr<mca::View>> CBViews =
788           CB->getPostInstrInfoViews(*IP, Insts);
789       for (auto &CBView : CBViews)
790         Printer.addView(std::move(CBView));
791     }
792 
793     if (PrintDispatchStats)
794       Printer.addView(std::make_unique<mca::DispatchStatistics>());
795 
796     if (PrintSchedulerStats)
797       Printer.addView(std::make_unique<mca::SchedulerStatistics>(*STI));
798 
799     if (PrintRetireStats)
800       Printer.addView(std::make_unique<mca::RetireControlUnitStatistics>(SM));
801 
802     if (PrintRegisterFileStats)
803       Printer.addView(std::make_unique<mca::RegisterFileStatistics>(*STI));
804 
805     if (PrintResourcePressureView)
806       Printer.addView(
807           std::make_unique<mca::ResourcePressureView>(*STI, *IP, Insts));
808 
809     if (PrintTimelineView) {
810       unsigned TimelineIterations =
811           TimelineMaxIterations ? TimelineMaxIterations : 10;
812       Printer.addView(std::make_unique<mca::TimelineView>(
813           *STI, *IP, Insts, std::min(TimelineIterations, S.getNumIterations()),
814           TimelineMaxCycles));
815     }
816 
817     // Fetch custom Views that are to be placed after all other Views.
818     // Refer to the comment paired with the CB->getStartViews(*IP, Insts); line
819     // for more info.
820     if (!DisableCustomBehaviour) {
821       std::vector<std::unique_ptr<mca::View>> CBViews =
822           CB->getEndViews(*IP, Insts);
823       for (auto &CBView : CBViews)
824         Printer.addView(std::move(CBView));
825     }
826 
827     if (!runPipeline(*P))
828       return 1;
829 
830     if (PrintJson) {
831       Printer.printReport(JSONOutput);
832     } else {
833       Printer.printReport(TOF->os());
834     }
835 
836     ++RegionIdx;
837   }
838 
839   if (NonEmptyRegions == 0) {
840     WithColor::error() << "no assembly instructions found.\n";
841     return 1;
842   }
843 
844   if (PrintJson)
845     TOF->os() << formatv("{0:2}", json::Value(std::move(JSONOutput))) << "\n";
846 
847   TOF->keep();
848   return 0;
849 }
850