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1//===-- PerfReader.cpp - perfscript reader  ---------------------*- 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-exception6//7//===----------------------------------------------------------------------===//8#include "PerfReader.h"9#include "ErrorHandling.h"10#include "Options.h"11#include "ProfileGenerator.h"12#include "llvm/ADT/SmallString.h"13#include "llvm/DebugInfo/Symbolize/SymbolizableModule.h"14#include "llvm/Support/FileSystem.h"15#include "llvm/Support/LineIterator.h"16#include "llvm/Support/MemoryBuffer.h"17#include "llvm/Support/Process.h"18#include "llvm/Support/ToolOutputFile.h"19 20#define DEBUG_TYPE "perf-reader"21 22namespace llvm {23 24cl::opt<bool> SkipSymbolization("skip-symbolization",25                                cl::desc("Dump the unsymbolized profile to the "26                                         "output file. It will show unwinder "27                                         "output for CS profile generation."),28                                cl::cat(ProfGenCategory));29 30static cl::opt<bool> ShowMmapEvents("show-mmap-events",31                                    cl::desc("Print binary load events."),32                                    cl::cat(ProfGenCategory));33 34static cl::opt<bool>35    UseOffset("use-offset", cl::init(true),36              cl::desc("Work with `--skip-symbolization` or "37                       "`--unsymbolized-profile` to write/read the "38                       "offset instead of virtual address."),39              cl::cat(ProfGenCategory));40 41static cl::opt<bool> UseLoadableSegmentAsBase(42    "use-first-loadable-segment-as-base",43    cl::desc("Use first loadable segment address as base address "44             "for offsets in unsymbolized profile. By default "45             "first executable segment address is used"),46    cl::cat(ProfGenCategory));47 48static cl::opt<bool>49    IgnoreStackSamples("ignore-stack-samples",50                       cl::desc("Ignore call stack samples for hybrid samples "51                                "and produce context-insensitive profile."),52                       cl::cat(ProfGenCategory));53cl::opt<bool> ShowDetailedWarning("show-detailed-warning",54                                  cl::desc("Show detailed warning message."),55                                  cl::cat(ProfGenCategory));56 57static cl::opt<int> CSProfMaxUnsymbolizedCtxDepth(58    "csprof-max-unsymbolized-context-depth", cl::init(-1),59    cl::desc("Keep the last K contexts while merging unsymbolized profile. -1 "60             "means no depth limit."),61    cl::cat(ProfGenCategory));62 63namespace sampleprof {64 65void VirtualUnwinder::unwindCall(UnwindState &State) {66  uint64_t Source = State.getCurrentLBRSource();67  auto *ParentFrame = State.getParentFrame();68  // The 2nd frame after leaf could be missing if stack sample is69  // taken when IP is within prolog/epilog, as frame chain isn't70  // setup yet. Fill in the missing frame in that case.71  // TODO: Currently we just assume all the addr that can't match the72  // 2nd frame is in prolog/epilog. In the future, we will switch to73  // pro/epi tracker(Dwarf CFI) for the precise check.74  if (ParentFrame == State.getDummyRootPtr() ||75      ParentFrame->Address != Source) {76    State.switchToFrame(Source);77    if (ParentFrame != State.getDummyRootPtr()) {78      if (Source == ExternalAddr)79        NumMismatchedExtCallBranch++;80      else81        NumMismatchedProEpiBranch++;82    }83  } else {84    State.popFrame();85  }86  State.InstPtr.update(Source);87}88 89void VirtualUnwinder::unwindLinear(UnwindState &State, uint64_t Repeat) {90  InstructionPointer &IP = State.InstPtr;91  uint64_t Target = State.getCurrentLBRTarget();92  uint64_t End = IP.Address;93 94  if (End == ExternalAddr && Target == ExternalAddr) {95    // Filter out the case when leaf external frame matches the external LBR96    // target, this is a valid state, it happens that the code run into external97    // address then return back.  The call frame under the external frame98    // remains valid and can be unwound later, just skip recording this range.99    NumPairedExtAddr++;100    return;101  }102 103  if (End == ExternalAddr || Target == ExternalAddr) {104    // Range is invalid if only one point is external address. This means LBR105    // traces contains a standalone external address failing to pair another106    // one, likely due to interrupt jmp or broken perf script. Set the107    // state to invalid.108    NumUnpairedExtAddr++;109    State.setInvalid();110    return;111  }112 113  if (!isValidFallThroughRange(Target, End, Binary)) {114    // Skip unwinding the rest of LBR trace when a bogus range is seen.115    State.setInvalid();116    return;117  }118 119  if (Binary->usePseudoProbes()) {120    // We don't need to top frame probe since it should be extracted121    // from the range.122    // The outcome of the virtual unwinding with pseudo probes is a123    // map from a context key to the address range being unwound.124    // This means basically linear unwinding is not needed for pseudo125    // probes. The range will be simply recorded here and will be126    // converted to a list of pseudo probes to report in ProfileGenerator.127    State.getParentFrame()->recordRangeCount(Target, End, Repeat);128  } else {129    // Unwind linear execution part.130    // Split and record the range by different inline context. For example:131    // [0x01] ... main:1          # Target132    // [0x02] ... main:2133    // [0x03] ... main:3 @ foo:1134    // [0x04] ... main:3 @ foo:2135    // [0x05] ... main:3 @ foo:3136    // [0x06] ... main:4137    // [0x07] ... main:5          # End138    // It will be recorded:139    // [main:*]         : [0x06, 0x07], [0x01, 0x02]140    // [main:3 @ foo:*] : [0x03, 0x05]141    while (IP.Address > Target) {142      uint64_t PrevIP = IP.Address;143      IP.backward();144      // Break into segments for implicit call/return due to inlining145      bool SameInlinee = Binary->inlineContextEqual(PrevIP, IP.Address);146      if (!SameInlinee) {147        State.switchToFrame(PrevIP);148        State.CurrentLeafFrame->recordRangeCount(PrevIP, End, Repeat);149        End = IP.Address;150      }151    }152    assert(IP.Address == Target && "The last one must be the target address.");153    // Record the remaining range, [0x01, 0x02] in the example154    State.switchToFrame(IP.Address);155    State.CurrentLeafFrame->recordRangeCount(IP.Address, End, Repeat);156  }157}158 159void VirtualUnwinder::unwindReturn(UnwindState &State) {160  // Add extra frame as we unwind through the return161  const LBREntry &LBR = State.getCurrentLBR();162  uint64_t CallAddr = Binary->getCallAddrFromFrameAddr(LBR.Target);163  State.switchToFrame(CallAddr);164  State.pushFrame(LBR.Source);165  State.InstPtr.update(LBR.Source);166}167 168void VirtualUnwinder::unwindBranch(UnwindState &State) {169  // TODO: Tolerate tail call for now, as we may see tail call from libraries.170  // This is only for intra function branches, excluding tail calls.171  uint64_t Source = State.getCurrentLBRSource();172  State.switchToFrame(Source);173  State.InstPtr.update(Source);174}175 176std::shared_ptr<StringBasedCtxKey> FrameStack::getContextKey() {177  std::shared_ptr<StringBasedCtxKey> KeyStr =178      std::make_shared<StringBasedCtxKey>();179  KeyStr->Context = Binary->getExpandedContext(Stack, KeyStr->WasLeafInlined);180  return KeyStr;181}182 183std::shared_ptr<AddrBasedCtxKey> AddressStack::getContextKey() {184  std::shared_ptr<AddrBasedCtxKey> KeyStr = std::make_shared<AddrBasedCtxKey>();185  KeyStr->Context = Stack;186  CSProfileGenerator::compressRecursionContext<uint64_t>(KeyStr->Context);187  // MaxContextDepth(--csprof-max-context-depth) is used to trim both symbolized188  // and unsymbolized profile context. Sometimes we want to at least preserve189  // the inlinings for the leaf frame(the profiled binary inlining),190  // --csprof-max-context-depth may not be flexible enough, in this case,191  // --csprof-max-unsymbolized-context-depth is used to limit the context for192  // unsymbolized profile. If both are set, use the minimum of them.193  int Depth = CSProfileGenerator::MaxContextDepth != -1194                  ? CSProfileGenerator::MaxContextDepth195                  : KeyStr->Context.size();196  Depth = CSProfMaxUnsymbolizedCtxDepth != -1197              ? std::min(static_cast<int>(CSProfMaxUnsymbolizedCtxDepth), Depth)198              : Depth;199  CSProfileGenerator::trimContext<uint64_t>(KeyStr->Context, Depth);200  return KeyStr;201}202 203template <typename T>204void VirtualUnwinder::collectSamplesFromFrame(UnwindState::ProfiledFrame *Cur,205                                              T &Stack) {206  if (Cur->RangeSamples.empty() && Cur->BranchSamples.empty())207    return;208 209  std::shared_ptr<ContextKey> Key = Stack.getContextKey();210  if (Key == nullptr)211    return;212  auto Ret = CtxCounterMap->emplace(Hashable<ContextKey>(Key), SampleCounter());213  SampleCounter &SCounter = Ret.first->second;214  for (auto &I : Cur->RangeSamples)215    SCounter.recordRangeCount(std::get<0>(I), std::get<1>(I), std::get<2>(I));216 217  for (auto &I : Cur->BranchSamples)218    SCounter.recordBranchCount(std::get<0>(I), std::get<1>(I), std::get<2>(I));219}220 221template <typename T>222void VirtualUnwinder::collectSamplesFromFrameTrie(223    UnwindState::ProfiledFrame *Cur, T &Stack) {224  if (!Cur->isDummyRoot()) {225    // Truncate the context for external frame since this isn't a real call226    // context the compiler will see.227    if (Cur->isExternalFrame() || !Stack.pushFrame(Cur)) {228      // Process truncated context229      // Start a new traversal ignoring its bottom context230      T EmptyStack(Binary);231      collectSamplesFromFrame(Cur, EmptyStack);232      for (const auto &Item : Cur->Children) {233        collectSamplesFromFrameTrie(Item.second.get(), EmptyStack);234      }235 236      // Keep note of untracked call site and deduplicate them237      // for warning later.238      if (!Cur->isLeafFrame())239        UntrackedCallsites.insert(Cur->Address);240 241      return;242    }243  }244 245  collectSamplesFromFrame(Cur, Stack);246  // Process children frame247  for (const auto &Item : Cur->Children) {248    collectSamplesFromFrameTrie(Item.second.get(), Stack);249  }250  // Recover the call stack251  Stack.popFrame();252}253 254void VirtualUnwinder::collectSamplesFromFrameTrie(255    UnwindState::ProfiledFrame *Cur) {256  if (Binary->usePseudoProbes()) {257    AddressStack Stack(Binary);258    collectSamplesFromFrameTrie<AddressStack>(Cur, Stack);259  } else {260    FrameStack Stack(Binary);261    collectSamplesFromFrameTrie<FrameStack>(Cur, Stack);262  }263}264 265void VirtualUnwinder::recordBranchCount(const LBREntry &Branch,266                                        UnwindState &State, uint64_t Repeat) {267  if (Branch.Target == ExternalAddr)268    return;269 270  // Record external-to-internal pattern on the trie root, it later can be271  // used for generating head samples.272  if (Branch.Source == ExternalAddr) {273    State.getDummyRootPtr()->recordBranchCount(Branch.Source, Branch.Target,274                                               Repeat);275    return;276  }277 278  if (Binary->usePseudoProbes()) {279    // Same as recordRangeCount, We don't need to top frame probe since we will280    // extract it from branch's source address281    State.getParentFrame()->recordBranchCount(Branch.Source, Branch.Target,282                                              Repeat);283  } else {284    State.CurrentLeafFrame->recordBranchCount(Branch.Source, Branch.Target,285                                              Repeat);286  }287}288 289bool VirtualUnwinder::unwind(const PerfSample *Sample, uint64_t Repeat) {290  // Capture initial state as starting point for unwinding.291  UnwindState State(Sample, Binary);292 293  // Sanity check - making sure leaf of LBR aligns with leaf of stack sample294  // Stack sample sometimes can be unreliable, so filter out bogus ones.295  if (!State.validateInitialState())296    return false;297 298  NumTotalBranches += State.LBRStack.size();299  // Now process the LBR samples in parrallel with stack sample300  // Note that we do not reverse the LBR entry order so we can301  // unwind the sample stack as we walk through LBR entries.302  while (State.hasNextLBR()) {303    State.checkStateConsistency();304 305    // Do not attempt linear unwind for the leaf range as it's incomplete.306    if (!State.IsLastLBR()) {307      // Unwind implicit calls/returns from inlining, along the linear path,308      // break into smaller sub section each with its own calling context.309      unwindLinear(State, Repeat);310    }311 312    // Save the LBR branch before it gets unwound.313    const LBREntry &Branch = State.getCurrentLBR();314    if (isCallState(State)) {315      // Unwind calls - we know we encountered call if LBR overlaps with316      // transition between leaf the 2nd frame. Note that for calls that317      // were not in the original stack sample, we should have added the318      // extra frame when processing the return paired with this call.319      unwindCall(State);320    } else if (isReturnState(State)) {321      // Unwind returns - check whether the IP is indeed at a return322      // instruction323      unwindReturn(State);324    } else if (isValidState(State)) {325      // Unwind branches326      unwindBranch(State);327    } else {328      // Skip unwinding the rest of LBR trace. Reset the stack and update the329      // state so that the rest of the trace can still be processed as if they330      // do not have stack samples.331      State.clearCallStack();332      State.InstPtr.update(State.getCurrentLBRSource());333      State.pushFrame(State.InstPtr.Address);334    }335 336    State.advanceLBR();337    // Record `branch` with calling context after unwinding.338    recordBranchCount(Branch, State, Repeat);339  }340  // As samples are aggregated on trie, record them into counter map341  collectSamplesFromFrameTrie(State.getDummyRootPtr());342 343  return true;344}345 346std::unique_ptr<PerfReaderBase>347PerfReaderBase::create(ProfiledBinary *Binary, PerfInputFile &PerfInput,348                       std::optional<int32_t> PIDFilter) {349  std::unique_ptr<PerfReaderBase> PerfReader;350 351  if (PerfInput.Format == PerfFormat::UnsymbolizedProfile) {352    PerfReader.reset(353        new UnsymbolizedProfileReader(Binary, PerfInput.InputFile));354    return PerfReader;355  }356 357  // For perf data input, we need to convert them into perf script first.358  // If this is a kernel perf file, there is no need for retrieving PIDs.359  if (PerfInput.Format == PerfFormat::PerfData)360    PerfInput = PerfScriptReader::convertPerfDataToTrace(361        Binary, Binary->isKernel(), PerfInput, PIDFilter);362 363  assert((PerfInput.Format == PerfFormat::PerfScript) &&364         "Should be a perfscript!");365 366  PerfInput.Content =367      PerfScriptReader::checkPerfScriptType(PerfInput.InputFile);368  if (PerfInput.Content == PerfContent::LBRStack) {369    PerfReader.reset(370        new HybridPerfReader(Binary, PerfInput.InputFile, PIDFilter));371  } else if (PerfInput.Content == PerfContent::LBR) {372    PerfReader.reset(new LBRPerfReader(Binary, PerfInput.InputFile, PIDFilter));373  } else {374    exitWithError("Unsupported perfscript!");375  }376 377  return PerfReader;378}379 380Error PerfReaderBase::parseDataAccessPerfTraces(381    StringRef DataAccessPerfTraceFile, std::optional<int32_t> PIDFilter) {382  // A perf_record_sample line is like383  // . 1282514022939813 0x87b0 [0x60]: PERF_RECORD_SAMPLE(IP, 0x4002):384  // 3446532/3446532: 0x2608a2 period: 233 addr: 0x3b3fb0385  constexpr static StringRef DataAccessSamplePattern =386      "PERF_RECORD_SAMPLE\\([A-Za-z]+, 0x[0-9a-fA-F]+\\): "387      "([0-9]+)\\/[0-9]+: 0x([0-9a-fA-F]+) period: [0-9]+ addr: "388      "0x([0-9a-fA-F]+)";389 390  llvm::Regex LogRegex(DataAccessSamplePattern);391 392  auto BufferOrErr = MemoryBuffer::getFile(DataAccessPerfTraceFile);393  std::error_code EC = BufferOrErr.getError();394  if (EC)395    return make_error<StringError>("Failed to open perf trace file: " +396                                       DataAccessPerfTraceFile,397                                   inconvertibleErrorCode());398 399  assert(!SampleCounters.empty() && "Sample counters should not be empty!");400  SampleCounter &Counter = SampleCounters.begin()->second;401  line_iterator LineIt(*BufferOrErr.get(), true);402 403  for (; !LineIt.is_at_eof(); ++LineIt) {404    StringRef Line = *LineIt;405 406    MMapEvent MMap;407    if (Line.contains("PERF_RECORD_MMAP2")) {408      if (PerfScriptReader::extractMMapEventForBinary(Binary, Line, MMap)) {409        if (!MMap.MemProtectionFlag.contains("x")) {410          if (Error E = Binary->addMMapNonTextEvent(MMap)) {411            return E;412          }413        }414      }415      continue;416    }417 418    SmallVector<StringRef> Fields;419    if (LogRegex.match(Line, &Fields)) {420      int32_t PID = 0;421      if (Fields[1].getAsInteger(10, PID))422        return make_error<StringError>(423            "Failed to parse PID from perf trace line: " + Line,424            inconvertibleErrorCode());425 426      if (PIDFilter.has_value() && *PIDFilter != PID) {427        continue;428      }429 430      uint64_t DataAddress = 0;431      if (Fields[3].getAsInteger(16, DataAddress))432        return make_error<StringError>(433            "Failed to parse data address from perf trace line: " + Line,434            inconvertibleErrorCode());435      // Out of all the memory access events, the vtable accesses are used to436      // construct type profiles. We assume that this is under the Itanium437      // C++ ABI so we can use `_ZTV` prefix to identify vtable.438      StringRef DataSymbol = Binary->symbolizeDataAddress(439          Binary->CanonicalizeNonTextAddress(DataAddress));440      if (DataSymbol.starts_with("_ZTV")) {441        uint64_t IP = 0;442        Fields[2].getAsInteger(16, IP);443        Counter.recordDataAccessCount(Binary->canonicalizeVirtualAddress(IP),444                                      DataSymbol, 1);445      }446    }447  }448  return Error::success();449}450 451PerfInputFile452PerfScriptReader::convertPerfDataToTrace(ProfiledBinary *Binary, bool SkipPID,453                                         PerfInputFile &File,454                                         std::optional<int32_t> PIDFilter) {455  StringRef PerfData = File.InputFile;456  // Run perf script to retrieve PIDs matching binary we're interested in.457  auto PerfExecutable = sys::Process::FindInEnvPath("PATH", "perf");458  if (!PerfExecutable) {459    exitWithError("Perf not found.");460  }461  std::string PerfPath = *PerfExecutable;462  SmallString<128> PerfTraceFile;463  sys::fs::createUniquePath("perf-script-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%.tmp",464                            PerfTraceFile, /*MakeAbsolute=*/true);465  std::string ErrorFile = std::string(PerfTraceFile) + ".err";466  std::optional<StringRef> Redirects[] = {std::nullopt,             // Stdin467                                          StringRef(PerfTraceFile), // Stdout468                                          StringRef(ErrorFile)};    // Stderr469  PerfScriptReader::TempFileCleanups.emplace_back(PerfTraceFile);470  PerfScriptReader::TempFileCleanups.emplace_back(ErrorFile);471 472  std::string PIDs;473  if (!SkipPID) {474    StringRef ScriptMMapArgs[] = {PerfPath, "script",   "--show-mmap-events",475                                  "-F",     "comm,pid", "-i",476                                  PerfData};477    sys::ExecuteAndWait(PerfPath, ScriptMMapArgs, std::nullopt, Redirects);478 479    // Collect the PIDs480    TraceStream TraceIt(PerfTraceFile);481    std::unordered_set<int32_t> PIDSet;482    while (!TraceIt.isAtEoF()) {483      MMapEvent MMap;484      if (isMMapEvent(TraceIt.getCurrentLine()) &&485          extractMMapEventForBinary(Binary, TraceIt.getCurrentLine(), MMap)) {486        auto It = PIDSet.emplace(MMap.PID);487        if (It.second && (!PIDFilter || MMap.PID == *PIDFilter)) {488          if (!PIDs.empty()) {489            PIDs.append(",");490          }491          PIDs.append(utostr(MMap.PID));492        }493      }494      TraceIt.advance();495    }496 497    if (PIDs.empty()) {498      exitWithError("No relevant mmap event is found in perf data.");499    }500  }501 502  // Run perf script again to retrieve events for PIDs collected above503  SmallVector<StringRef, 8> ScriptSampleArgs;504  ScriptSampleArgs.push_back(PerfPath);505  ScriptSampleArgs.push_back("script");506  ScriptSampleArgs.push_back("--show-mmap-events");507  ScriptSampleArgs.push_back("-F");508  ScriptSampleArgs.push_back("ip,brstack");509  ScriptSampleArgs.push_back("-i");510  ScriptSampleArgs.push_back(PerfData);511  if (!PIDs.empty()) {512    ScriptSampleArgs.push_back("--pid");513    ScriptSampleArgs.push_back(PIDs);514  }515  sys::ExecuteAndWait(PerfPath, ScriptSampleArgs, std::nullopt, Redirects);516 517  return {std::string(PerfTraceFile), PerfFormat::PerfScript,518          PerfContent::UnknownContent};519}520 521static StringRef filename(StringRef Path, bool UseBackSlash) {522  llvm::sys::path::Style PathStyle =523      UseBackSlash ? llvm::sys::path::Style::windows_backslash524                   : llvm::sys::path::Style::native;525  StringRef FileName = llvm::sys::path::filename(Path, PathStyle);526 527  // In case this file use \r\n as newline.528  if (UseBackSlash && FileName.back() == '\r')529    return FileName.drop_back();530 531  return FileName;532}533 534void PerfScriptReader::updateBinaryAddress(const MMapEvent &Event) {535  // Drop the event which doesn't belong to user-provided binary536  StringRef BinaryName = filename(Event.BinaryPath, Binary->isCOFF());537  bool IsKernel = Binary->isKernel();538  if (!IsKernel && Binary->getName() != BinaryName)539    return;540  if (IsKernel && !Binary->isKernelImageName(BinaryName))541    return;542 543  // Drop the event if process does not match pid filter544  if (PIDFilter && Event.PID != *PIDFilter)545    return;546 547  // Drop the event if its image is loaded at the same address548  if (Event.Address == Binary->getBaseAddress()) {549    Binary->setIsLoadedByMMap(true);550    return;551  }552 553  if (IsKernel || Event.Offset == Binary->getTextSegmentOffset()) {554    // A binary image could be unloaded and then reloaded at different555    // place, so update binary load address.556    // Only update for the first executable segment and assume all other557    // segments are loaded at consecutive memory addresses, which is the case on558    // X64.559    Binary->setBaseAddress(Event.Address);560    Binary->setIsLoadedByMMap(true);561  } else {562    // Verify segments are loaded consecutively.563    const auto &Offsets = Binary->getTextSegmentOffsets();564    auto It = llvm::lower_bound(Offsets, Event.Offset);565    if (It != Offsets.end() && *It == Event.Offset) {566      // The event is for loading a separate executable segment.567      auto I = std::distance(Offsets.begin(), It);568      const auto &PreferredAddrs = Binary->getPreferredTextSegmentAddresses();569      if (PreferredAddrs[I] - Binary->getPreferredBaseAddress() !=570          Event.Address - Binary->getBaseAddress())571        exitWithError("Executable segments not loaded consecutively");572    } else {573      if (It == Offsets.begin())574        exitWithError("File offset not found");575      else {576        // Find the segment the event falls in. A large segment could be loaded577        // via multiple mmap calls with consecutive memory addresses.578        --It;579        assert(*It < Event.Offset);580        if (Event.Offset - *It != Event.Address - Binary->getBaseAddress())581          exitWithError("Segment not loaded by consecutive mmaps");582      }583    }584  }585}586 587static std::string getContextKeyStr(ContextKey *K,588                                    const ProfiledBinary *Binary) {589  if (const auto *CtxKey = dyn_cast<StringBasedCtxKey>(K)) {590    return SampleContext::getContextString(CtxKey->Context);591  } else if (const auto *CtxKey = dyn_cast<AddrBasedCtxKey>(K)) {592    std::ostringstream OContextStr;593    for (uint32_t I = 0; I < CtxKey->Context.size(); I++) {594      if (OContextStr.str().size())595        OContextStr << " @ ";596      uint64_t Address = CtxKey->Context[I];597      if (UseOffset) {598        if (UseLoadableSegmentAsBase)599          Address -= Binary->getFirstLoadableAddress();600        else601          Address -= Binary->getPreferredBaseAddress();602      }603      OContextStr << "0x"604                  << utohexstr(Address,605                               /*LowerCase=*/true);606    }607    return OContextStr.str();608  } else {609    llvm_unreachable("unexpected key type");610  }611}612 613void HybridPerfReader::unwindSamples() {614  VirtualUnwinder Unwinder(&SampleCounters, Binary);615  for (const auto &Item : AggregatedSamples) {616    const PerfSample *Sample = Item.first.getPtr();617    Unwinder.unwind(Sample, Item.second);618  }619 620  // Warn about untracked frames due to missing probes.621  if (ShowDetailedWarning) {622    for (auto Address : Unwinder.getUntrackedCallsites())623      WithColor::warning() << "Profile context truncated due to missing probe "624                           << "for call instruction at "625                           << format("0x%" PRIx64, Address) << "\n";626  }627 628  emitWarningSummary(Unwinder.getUntrackedCallsites().size(),629                     SampleCounters.size(),630                     "of profiled contexts are truncated due to missing probe "631                     "for call instruction.");632 633  emitWarningSummary(634      Unwinder.NumMismatchedExtCallBranch, Unwinder.NumTotalBranches,635      "of branches'source is a call instruction but doesn't match call frame "636      "stack, likely due to unwinding error of external frame.");637 638  emitWarningSummary(Unwinder.NumPairedExtAddr * 2, Unwinder.NumTotalBranches,639                     "of branches containing paired external address.");640 641  emitWarningSummary(Unwinder.NumUnpairedExtAddr, Unwinder.NumTotalBranches,642                     "of branches containing external address but doesn't have "643                     "another external address to pair, likely due to "644                     "interrupt jmp or broken perf script.");645 646  emitWarningSummary(647      Unwinder.NumMismatchedProEpiBranch, Unwinder.NumTotalBranches,648      "of branches'source is a call instruction but doesn't match call frame "649      "stack, likely due to frame in prolog/epilog.");650 651  emitWarningSummary(Unwinder.NumMissingExternalFrame,652                     Unwinder.NumExtCallBranch,653                     "of artificial call branches but doesn't have an external "654                     "frame to match.");655}656 657bool PerfScriptReader::extractLBRStack(TraceStream &TraceIt,658                                       SmallVectorImpl<LBREntry> &LBRStack) {659  // The raw format of LBR stack is like:660  // 0x4005c8/0x4005dc/P/-/-/0 0x40062f/0x4005b0/P/-/-/0 ...661  //                           ... 0x4005c8/0x4005dc/P/-/-/0662  // It's in FIFO order and separated by whitespace.663  SmallVector<StringRef, 32> Records;664  TraceIt.getCurrentLine().rtrim().split(Records, " ", -1, false);665  auto WarnInvalidLBR = [](TraceStream &TraceIt) {666    WithColor::warning() << "Invalid address in LBR record at line "667                         << TraceIt.getLineNumber() << ": "668                         << TraceIt.getCurrentLine() << "\n";669  };670 671  // Skip the leading instruction pointer.672  size_t Index = 0;673  uint64_t LeadingAddr;674  if (!Records.empty() && !Records[0].contains('/')) {675    if (Records[0].getAsInteger(16, LeadingAddr)) {676      WarnInvalidLBR(TraceIt);677      TraceIt.advance();678      return false;679    }680    Index = 1;681  }682 683  // Now extract LBR samples - note that we do not reverse the684  // LBR entry order so we can unwind the sample stack as we walk685  // through LBR entries.686  while (Index < Records.size()) {687    auto &Token = Records[Index++];688    if (Token.size() == 0)689      continue;690 691    SmallVector<StringRef, 8> Addresses;692    Token.split(Addresses, "/");693    uint64_t Src;694    uint64_t Dst;695 696    // Stop at broken LBR records.697    if (Addresses.size() < 2 || Addresses[0].substr(2).getAsInteger(16, Src) ||698        Addresses[1].substr(2).getAsInteger(16, Dst)) {699      WarnInvalidLBR(TraceIt);700      break;701    }702 703    // Canonicalize to use preferred load address as base address.704    Src = Binary->canonicalizeVirtualAddress(Src);705    Dst = Binary->canonicalizeVirtualAddress(Dst);706    bool SrcIsInternal = Binary->addressIsCode(Src);707    bool DstIsInternal = Binary->addressIsCode(Dst);708    if (!SrcIsInternal)709      Src = ExternalAddr;710    if (!DstIsInternal)711      Dst = ExternalAddr;712    // Filter external-to-external case to reduce LBR trace size.713    if (!SrcIsInternal && !DstIsInternal)714      continue;715 716    LBRStack.emplace_back(LBREntry(Src, Dst));717  }718  TraceIt.advance();719  return !LBRStack.empty();720}721 722bool PerfScriptReader::extractCallstack(TraceStream &TraceIt,723                                        SmallVectorImpl<uint64_t> &CallStack) {724  // The raw format of call stack is like:725  //            4005dc      # leaf frame726  //	          400634727  //	          400684      # root frame728  // It's in bottom-up order with each frame in one line.729 730  // Extract stack frames from sample731  while (!TraceIt.isAtEoF() && !TraceIt.getCurrentLine().starts_with(" 0x")) {732    StringRef FrameStr = TraceIt.getCurrentLine().ltrim();733    uint64_t FrameAddr = 0;734    if (FrameStr.getAsInteger(16, FrameAddr)) {735      // We might parse a non-perf sample line like empty line and comments,736      // skip it737      TraceIt.advance();738      return false;739    }740    TraceIt.advance();741 742    FrameAddr = Binary->canonicalizeVirtualAddress(FrameAddr);743    // Currently intermixed frame from different binaries is not supported.744    if (!Binary->addressIsCode(FrameAddr)) {745      if (CallStack.empty())746        NumLeafExternalFrame++;747      // Push a special value(ExternalAddr) for the external frames so that748      // unwinder can still work on this with artificial Call/Return branch.749      // After unwinding, the context will be truncated for external frame.750      // Also deduplicate the consecutive external addresses.751      if (CallStack.empty() || CallStack.back() != ExternalAddr)752        CallStack.emplace_back(ExternalAddr);753      continue;754    }755 756    // We need to translate return address to call address for non-leaf frames.757    if (!CallStack.empty()) {758      auto CallAddr = Binary->getCallAddrFromFrameAddr(FrameAddr);759      if (!CallAddr) {760        // Stop at an invalid return address caused by bad unwinding. This could761        // happen to frame-pointer-based unwinding and the callee functions that762        // do not have the frame pointer chain set up.763        InvalidReturnAddresses.insert(FrameAddr);764        break;765      }766      FrameAddr = CallAddr;767    }768 769    CallStack.emplace_back(FrameAddr);770  }771 772  // Strip out the bottom external addr.773  if (CallStack.size() > 1 && CallStack.back() == ExternalAddr)774    CallStack.pop_back();775 776  // Skip other unrelated line, find the next valid LBR line777  // Note that even for empty call stack, we should skip the address at the778  // bottom, otherwise the following pass may generate a truncated callstack779  while (!TraceIt.isAtEoF() && !TraceIt.getCurrentLine().starts_with(" 0x")) {780    TraceIt.advance();781  }782  // Filter out broken stack sample. We may not have complete frame info783  // if sample end up in prolog/epilog, the result is dangling context not784  // connected to entry point. This should be relatively rare thus not much785  // impact on overall profile quality. However we do want to filter them786  // out to reduce the number of different calling contexts. One instance787  // of such case - when sample landed in prolog/epilog, somehow stack788  // walking will be broken in an unexpected way that higher frames will be789  // missing.790  return !CallStack.empty() &&791         !Binary->addressInPrologEpilog(CallStack.front());792}793 794void PerfScriptReader::warnIfMissingMMap() {795  if (!Binary->getMissingMMapWarned() && !Binary->getIsLoadedByMMap()) {796    WithColor::warning() << "No relevant mmap event is matched for "797                         << Binary->getName()798                         << ", will use preferred address ("799                         << format("0x%" PRIx64,800                                   Binary->getPreferredBaseAddress())801                         << ") as the base loading address!\n";802    // Avoid redundant warning, only warn at the first unmatched sample.803    Binary->setMissingMMapWarned(true);804  }805}806 807void HybridPerfReader::parseSample(TraceStream &TraceIt, uint64_t Count) {808  // The raw hybird sample started with call stack in FILO order and followed809  // intermediately by LBR sample810  // e.g.811  // 	          4005dc    # call stack leaf812  //	          400634813  //	          400684    # call stack root814  // 0x4005c8/0x4005dc/P/-/-/0   0x40062f/0x4005b0/P/-/-/0 ...815  //          ... 0x4005c8/0x4005dc/P/-/-/0    # LBR Entries816  //817  std::shared_ptr<PerfSample> Sample = std::make_shared<PerfSample>();818#ifndef NDEBUG819  Sample->Linenum = TraceIt.getLineNumber();820#endif821  // Parsing call stack and populate into PerfSample.CallStack822  if (!extractCallstack(TraceIt, Sample->CallStack)) {823    // Skip the next LBR line matched current call stack824    if (!TraceIt.isAtEoF() && TraceIt.getCurrentLine().starts_with(" 0x"))825      TraceIt.advance();826    return;827  }828 829  warnIfMissingMMap();830 831  if (!TraceIt.isAtEoF() && TraceIt.getCurrentLine().starts_with(" 0x")) {832    // Parsing LBR stack and populate into PerfSample.LBRStack833    if (extractLBRStack(TraceIt, Sample->LBRStack)) {834      if (IgnoreStackSamples) {835        Sample->CallStack.clear();836      } else {837        // Canonicalize stack leaf to avoid 'random' IP from leaf frame skew LBR838        // ranges839        Sample->CallStack.front() = Sample->LBRStack[0].Target;840      }841      // Record samples by aggregation842      AggregatedSamples[Hashable<PerfSample>(Sample)] += Count;843    }844  } else {845    // LBR sample is encoded in single line after stack sample846    exitWithError("'Hybrid perf sample is corrupted, No LBR sample line");847  }848}849 850void PerfScriptReader::writeUnsymbolizedProfile(StringRef Filename) {851  std::error_code EC;852  raw_fd_ostream OS(Filename, EC, llvm::sys::fs::OF_TextWithCRLF);853  if (EC)854    exitWithError(EC, Filename);855  writeUnsymbolizedProfile(OS);856}857 858// Use ordered map to make the output deterministic859using OrderedCounterForPrint = std::map<std::string, SampleCounter *>;860 861void PerfScriptReader::writeUnsymbolizedProfile(raw_fd_ostream &OS) {862  OrderedCounterForPrint OrderedCounters;863  for (auto &CI : SampleCounters) {864    OrderedCounters[getContextKeyStr(CI.first.getPtr(), Binary)] = &CI.second;865  }866 867  auto SCounterPrinter = [&](RangeSample &Counter, StringRef Separator,868                             uint32_t Indent) {869    OS.indent(Indent);870    OS << Counter.size() << "\n";871    for (auto &I : Counter) {872      uint64_t Start = I.first.first;873      uint64_t End = I.first.second;874 875      if (UseOffset) {876        if (UseLoadableSegmentAsBase) {877          Start -= Binary->getFirstLoadableAddress();878          End -= Binary->getFirstLoadableAddress();879        } else {880          Start -= Binary->getPreferredBaseAddress();881          End -= Binary->getPreferredBaseAddress();882        }883      }884 885      OS.indent(Indent);886      OS << Twine::utohexstr(Start) << Separator << Twine::utohexstr(End) << ":"887         << I.second << "\n";888    }889  };890 891  for (auto &CI : OrderedCounters) {892    uint32_t Indent = 0;893    if (ProfileIsCS) {894      // Context string key895      OS << "[" << CI.first << "]\n";896      Indent = 2;897    }898 899    SampleCounter &Counter = *CI.second;900    SCounterPrinter(Counter.RangeCounter, "-", Indent);901    SCounterPrinter(Counter.BranchCounter, "->", Indent);902  }903}904 905// Format of input:906// number of entries in RangeCounter907// from_1-to_1:count_1908// from_2-to_2:count_2909// ......910// from_n-to_n:count_n911// number of entries in BranchCounter912// src_1->dst_1:count_1913// src_2->dst_2:count_2914// ......915// src_n->dst_n:count_n916void UnsymbolizedProfileReader::readSampleCounters(TraceStream &TraceIt,917                                                   SampleCounter &SCounters) {918  auto exitWithErrorForTraceLine = [](TraceStream &TraceIt) {919    std::string Msg = TraceIt.isAtEoF()920                          ? "Invalid raw profile!"921                          : "Invalid raw profile at line " +922                                Twine(TraceIt.getLineNumber()).str() + ": " +923                                TraceIt.getCurrentLine().str();924    exitWithError(Msg);925  };926  auto ReadNumber = [&](uint64_t &Num) {927    if (TraceIt.isAtEoF())928      exitWithErrorForTraceLine(TraceIt);929    if (TraceIt.getCurrentLine().ltrim().getAsInteger(10, Num))930      exitWithErrorForTraceLine(TraceIt);931    TraceIt.advance();932  };933 934  auto ReadCounter = [&](RangeSample &Counter, StringRef Separator) {935    uint64_t Num = 0;936    ReadNumber(Num);937    while (Num--) {938      if (TraceIt.isAtEoF())939        exitWithErrorForTraceLine(TraceIt);940      StringRef Line = TraceIt.getCurrentLine().ltrim();941 942      uint64_t Count = 0;943      auto LineSplit = Line.split(":");944      if (LineSplit.second.empty() || LineSplit.second.getAsInteger(10, Count))945        exitWithErrorForTraceLine(TraceIt);946 947      uint64_t Source = 0;948      uint64_t Target = 0;949      auto Range = LineSplit.first.split(Separator);950      if (Range.second.empty() || Range.first.getAsInteger(16, Source) ||951          Range.second.getAsInteger(16, Target))952        exitWithErrorForTraceLine(TraceIt);953 954      if (UseOffset) {955        if (UseLoadableSegmentAsBase) {956          Source += Binary->getFirstLoadableAddress();957          Target += Binary->getFirstLoadableAddress();958        } else {959          Source += Binary->getPreferredBaseAddress();960          Target += Binary->getPreferredBaseAddress();961        }962      }963 964      Counter[{Source, Target}] += Count;965      TraceIt.advance();966    }967  };968 969  ReadCounter(SCounters.RangeCounter, "-");970  ReadCounter(SCounters.BranchCounter, "->");971}972 973void UnsymbolizedProfileReader::readUnsymbolizedProfile(StringRef FileName) {974  TraceStream TraceIt(FileName);975  while (!TraceIt.isAtEoF()) {976    std::shared_ptr<StringBasedCtxKey> Key =977        std::make_shared<StringBasedCtxKey>();978    StringRef Line = TraceIt.getCurrentLine();979    // Read context stack for CS profile.980    if (Line.starts_with("[")) {981      ProfileIsCS = true;982      auto I = ContextStrSet.insert(Line.str());983      SampleContext::createCtxVectorFromStr(*I.first, Key->Context);984      TraceIt.advance();985    }986    auto Ret =987        SampleCounters.emplace(Hashable<ContextKey>(Key), SampleCounter());988    readSampleCounters(TraceIt, Ret.first->second);989  }990}991 992void UnsymbolizedProfileReader::parsePerfTraces() {993  readUnsymbolizedProfile(PerfTraceFile);994}995 996void PerfScriptReader::computeCounterFromLBR(const PerfSample *Sample,997                                             uint64_t Repeat) {998  SampleCounter &Counter = SampleCounters.begin()->second;999  uint64_t EndAddress = 0;1000  for (const LBREntry &LBR : Sample->LBRStack) {1001    uint64_t SourceAddress = LBR.Source;1002    uint64_t TargetAddress = LBR.Target;1003 1004    // Record the branch if its SourceAddress is external. It can be the case an1005    // external source call an internal function, later this branch will be used1006    // to generate the function's head sample.1007    if (Binary->addressIsCode(TargetAddress)) {1008      Counter.recordBranchCount(SourceAddress, TargetAddress, Repeat);1009    }1010 1011    // If this not the first LBR, update the range count between TO of current1012    // LBR and FROM of next LBR.1013    uint64_t StartAddress = TargetAddress;1014    if (Binary->addressIsCode(StartAddress) &&1015        Binary->addressIsCode(EndAddress) &&1016        isValidFallThroughRange(StartAddress, EndAddress, Binary))1017      Counter.recordRangeCount(StartAddress, EndAddress, Repeat);1018    EndAddress = SourceAddress;1019  }1020}1021 1022void LBRPerfReader::parseSample(TraceStream &TraceIt, uint64_t Count) {1023  std::shared_ptr<PerfSample> Sample = std::make_shared<PerfSample>();1024  // Parsing LBR stack and populate into PerfSample.LBRStack1025  if (extractLBRStack(TraceIt, Sample->LBRStack)) {1026    warnIfMissingMMap();1027    // Record LBR only samples by aggregation1028    AggregatedSamples[Hashable<PerfSample>(Sample)] += Count;1029  }1030}1031 1032void PerfScriptReader::generateUnsymbolizedProfile() {1033  // There is no context for LBR only sample, so initialize one entry with1034  // fake "empty" context key.1035  assert(SampleCounters.empty() &&1036         "Sample counter map should be empty before raw profile generation");1037  std::shared_ptr<StringBasedCtxKey> Key =1038      std::make_shared<StringBasedCtxKey>();1039  SampleCounters.emplace(Hashable<ContextKey>(Key), SampleCounter());1040  for (const auto &Item : AggregatedSamples) {1041    const PerfSample *Sample = Item.first.getPtr();1042    computeCounterFromLBR(Sample, Item.second);1043  }1044}1045 1046uint64_t PerfScriptReader::parseAggregatedCount(TraceStream &TraceIt) {1047  // The aggregated count is optional, so do not skip the line and return 1 if1048  // it's unmatched1049  uint64_t Count = 1;1050  if (!TraceIt.getCurrentLine().getAsInteger(10, Count))1051    TraceIt.advance();1052  return Count;1053}1054 1055void PerfScriptReader::parseSample(TraceStream &TraceIt) {1056  NumTotalSample++;1057  uint64_t Count = parseAggregatedCount(TraceIt);1058  assert(Count >= 1 && "Aggregated count should be >= 1!");1059  parseSample(TraceIt, Count);1060}1061 1062bool PerfScriptReader::extractMMapEventForBinary(ProfiledBinary *Binary,1063                                                 StringRef Line,1064                                                 MMapEvent &MMap) {1065  // Parse a MMap2 line like:1066  //  PERF_RECORD_MMAP2 2113428/2113428: [0x7fd4efb57000(0x204000) @ 01067  //  08:04 19532229 3585508847]: r-xp /usr/lib64/libdl-2.17.so1068  constexpr static const char *const MMap2Pattern =1069      "PERF_RECORD_MMAP2 (-?[0-9]+)/[0-9]+: "1070      "\\[(0x[a-f0-9]+)\\((0x[a-f0-9]+)\\) @ "1071      "(0x[a-f0-9]+|0) .*\\]: ([-a-z]+) (.*)";1072  // Parse a MMap line like1073  // PERF_RECORD_MMAP -1/0: [0xffffffff81e00000(0x3e8fa000) @ \1074  //  0xffffffff81e00000]: x [kernel.kallsyms]_text1075  constexpr static const char *const MMapPattern =1076      "PERF_RECORD_MMAP (-?[0-9]+)/[0-9]+: "1077      "\\[(0x[a-f0-9]+)\\((0x[a-f0-9]+)\\) @ "1078      "(0x[a-f0-9]+|0)\\]: ([-a-z]+) (.*)";1079  // Field 0 - whole line1080  // Field 1 - PID1081  // Field 2 - base address1082  // Field 3 - mmapped size1083  // Field 4 - page offset1084  // Field 5 - binary path1085  enum EventIndex {1086    WHOLE_LINE = 0,1087    PID = 1,1088    MMAPPED_ADDRESS = 2,1089    MMAPPED_SIZE = 3,1090    PAGE_OFFSET = 4,1091    MEM_PROTECTION_FLAG = 5,1092    BINARY_PATH = 6,1093  };1094 1095  bool R = false;1096  SmallVector<StringRef, 7> Fields;1097  if (Line.contains("PERF_RECORD_MMAP2 ")) {1098    Regex RegMmap2(MMap2Pattern);1099    R = RegMmap2.match(Line, &Fields);1100  } else if (Line.contains("PERF_RECORD_MMAP ")) {1101    Regex RegMmap(MMapPattern);1102    R = RegMmap.match(Line, &Fields);1103  } else1104    llvm_unreachable("unexpected MMAP event entry");1105 1106  if (!R) {1107    std::string WarningMsg = "Cannot parse mmap event: " + Line.str() + " \n";1108    WithColor::warning() << WarningMsg;1109    return false;1110  }1111  long long MMapPID = 0;1112  getAsSignedInteger(Fields[PID], 10, MMapPID);1113  MMap.PID = MMapPID;1114  Fields[MMAPPED_ADDRESS].getAsInteger(0, MMap.Address);1115  Fields[MMAPPED_SIZE].getAsInteger(0, MMap.Size);1116  Fields[PAGE_OFFSET].getAsInteger(0, MMap.Offset);1117  MMap.MemProtectionFlag = Fields[MEM_PROTECTION_FLAG];1118  MMap.BinaryPath = Fields[BINARY_PATH];1119  if (ShowMmapEvents) {1120    outs() << "Mmap: Binary " << MMap.BinaryPath << " loaded at "1121           << format("0x%" PRIx64 ":", MMap.Address) << " \n";1122  }1123 1124  StringRef BinaryName = filename(MMap.BinaryPath, Binary->isCOFF());1125  if (Binary->isKernel()) {1126    return Binary->isKernelImageName(BinaryName);1127  }1128  return Binary->getName() == BinaryName;1129}1130 1131void PerfScriptReader::parseMMapEvent(TraceStream &TraceIt) {1132  MMapEvent MMap;1133  if (extractMMapEventForBinary(Binary, TraceIt.getCurrentLine(), MMap))1134    updateBinaryAddress(MMap);1135  TraceIt.advance();1136}1137 1138void PerfScriptReader::parseEventOrSample(TraceStream &TraceIt) {1139  if (isMMapEvent(TraceIt.getCurrentLine()))1140    parseMMapEvent(TraceIt);1141  else1142    parseSample(TraceIt);1143}1144 1145void PerfScriptReader::parseAndAggregateTrace() {1146  // Trace line iterator1147  TraceStream TraceIt(PerfTraceFile);1148  while (!TraceIt.isAtEoF())1149    parseEventOrSample(TraceIt);1150}1151 1152// A LBR sample is like:1153// 40062f 0x5c6313f/0x5c63170/P/-/-/0  0x5c630e7/0x5c63130/P/-/-/0 ...1154// A heuristic for fast detection by checking whether a1155// leading "  0x" and the '/' exist.1156bool PerfScriptReader::isLBRSample(StringRef Line) {1157  // Skip the leading instruction pointer1158  SmallVector<StringRef, 32> Records;1159  Line.trim().split(Records, " ", 2, false);1160  if (Records.size() < 2)1161    return false;1162  if (Records[1].starts_with("0x") && Records[1].contains('/'))1163    return true;1164  return false;1165}1166 1167bool PerfScriptReader::isMMapEvent(StringRef Line) {1168  // Short cut to avoid string find is possible.1169  if (Line.empty() || Line.size() < 50)1170    return false;1171 1172  if (std::isdigit(Line[0]))1173    return false;1174 1175  // PERF_RECORD_MMAP2 or PERF_RECORD_MMAP does not appear at the beginning of1176  // the line for ` perf script  --show-mmap-events  -i ...`1177  return Line.contains("PERF_RECORD_MMAP");1178}1179 1180// The raw hybird sample is like1181// e.g.1182// 	          4005dc    # call stack leaf1183//	          4006341184//	          400684    # call stack root1185// 0x4005c8/0x4005dc/P/-/-/0   0x40062f/0x4005b0/P/-/-/0 ...1186//          ... 0x4005c8/0x4005dc/P/-/-/0    # LBR Entries1187// Determine the perfscript contains hybrid samples(call stack + LBRs) by1188// checking whether there is a non-empty call stack immediately followed by1189// a LBR sample1190PerfContent PerfScriptReader::checkPerfScriptType(StringRef FileName) {1191  TraceStream TraceIt(FileName);1192  uint64_t FrameAddr = 0;1193  while (!TraceIt.isAtEoF()) {1194    // Skip the aggregated count1195    if (!TraceIt.getCurrentLine().getAsInteger(10, FrameAddr))1196      TraceIt.advance();1197 1198    // Detect sample with call stack1199    int32_t Count = 0;1200    while (!TraceIt.isAtEoF() &&1201           !TraceIt.getCurrentLine().ltrim().getAsInteger(16, FrameAddr)) {1202      Count++;1203      TraceIt.advance();1204    }1205    if (!TraceIt.isAtEoF()) {1206      if (isLBRSample(TraceIt.getCurrentLine())) {1207        if (Count > 0)1208          return PerfContent::LBRStack;1209        else1210          return PerfContent::LBR;1211      }1212      TraceIt.advance();1213    }1214  }1215 1216  exitWithError("Invalid perf script input!");1217  return PerfContent::UnknownContent;1218}1219 1220void HybridPerfReader::generateUnsymbolizedProfile() {1221  ProfileIsCS = !IgnoreStackSamples;1222  if (ProfileIsCS)1223    unwindSamples();1224  else1225    PerfScriptReader::generateUnsymbolizedProfile();1226}1227 1228void PerfScriptReader::warnTruncatedStack() {1229  if (ShowDetailedWarning) {1230    for (auto Address : InvalidReturnAddresses) {1231      WithColor::warning()1232          << "Truncated stack sample due to invalid return address at "1233          << format("0x%" PRIx64, Address)1234          << ", likely caused by frame pointer omission\n";1235    }1236  }1237  emitWarningSummary(1238      InvalidReturnAddresses.size(), AggregatedSamples.size(),1239      "of truncated stack samples due to invalid return address, "1240      "likely caused by frame pointer omission.");1241}1242 1243void PerfScriptReader::warnInvalidRange() {1244  std::unordered_map<std::pair<uint64_t, uint64_t>, uint64_t,1245                     pair_hash<uint64_t, uint64_t>>1246      Ranges;1247 1248  for (const auto &Item : AggregatedSamples) {1249    const PerfSample *Sample = Item.first.getPtr();1250    uint64_t Count = Item.second;1251    uint64_t EndAddress = 0;1252    for (const LBREntry &LBR : Sample->LBRStack) {1253      uint64_t SourceAddress = LBR.Source;1254      uint64_t StartAddress = LBR.Target;1255      if (EndAddress != 0)1256        Ranges[{StartAddress, EndAddress}] += Count;1257      EndAddress = SourceAddress;1258    }1259  }1260 1261  if (Ranges.empty()) {1262    WithColor::warning() << "No samples in perf script!\n";1263    return;1264  }1265 1266  auto WarnInvalidRange = [&](uint64_t StartAddress, uint64_t EndAddress,1267                              StringRef Msg) {1268    if (!ShowDetailedWarning)1269      return;1270    WithColor::warning() << "[" << format("%8" PRIx64, StartAddress) << ","1271                         << format("%8" PRIx64, EndAddress) << "]: " << Msg1272                         << "\n";1273  };1274 1275  const char *EndNotBoundaryMsg = "Range is not on instruction boundary, "1276                                  "likely due to profile and binary mismatch.";1277  const char *DanglingRangeMsg = "Range does not belong to any functions, "1278                                 "likely from PLT, .init or .fini section.";1279  const char *RangeCrossFuncMsg =1280      "Fall through range should not cross function boundaries, likely due to "1281      "profile and binary mismatch.";1282  const char *BogusRangeMsg = "Range start is after or too far from range end.";1283 1284  uint64_t TotalRangeNum = 0;1285  uint64_t InstNotBoundary = 0;1286  uint64_t UnmatchedRange = 0;1287  uint64_t RangeCrossFunc = 0;1288  uint64_t BogusRange = 0;1289 1290  for (auto &I : Ranges) {1291    uint64_t StartAddress = I.first.first;1292    uint64_t EndAddress = I.first.second;1293    TotalRangeNum += I.second;1294 1295    if (!Binary->addressIsCode(StartAddress) &&1296        !Binary->addressIsCode(EndAddress))1297      continue;1298 1299    if (!Binary->addressIsCode(StartAddress) ||1300        !Binary->addressIsTransfer(EndAddress)) {1301      InstNotBoundary += I.second;1302      WarnInvalidRange(StartAddress, EndAddress, EndNotBoundaryMsg);1303    }1304 1305    auto *FRange = Binary->findFuncRange(StartAddress);1306    if (!FRange) {1307      UnmatchedRange += I.second;1308      WarnInvalidRange(StartAddress, EndAddress, DanglingRangeMsg);1309      continue;1310    }1311 1312    if (EndAddress >= FRange->EndAddress) {1313      RangeCrossFunc += I.second;1314      WarnInvalidRange(StartAddress, EndAddress, RangeCrossFuncMsg);1315    }1316 1317    if (Binary->addressIsCode(StartAddress) &&1318        Binary->addressIsCode(EndAddress) &&1319        !isValidFallThroughRange(StartAddress, EndAddress, Binary)) {1320      BogusRange += I.second;1321      WarnInvalidRange(StartAddress, EndAddress, BogusRangeMsg);1322    }1323  }1324 1325  emitWarningSummary(1326      InstNotBoundary, TotalRangeNum,1327      "of samples are from ranges that are not on instruction boundary.");1328  emitWarningSummary(1329      UnmatchedRange, TotalRangeNum,1330      "of samples are from ranges that do not belong to any functions.");1331  emitWarningSummary(1332      RangeCrossFunc, TotalRangeNum,1333      "of samples are from ranges that do cross function boundaries.");1334  emitWarningSummary(1335      BogusRange, TotalRangeNum,1336      "of samples are from ranges that have range start after or too far from "1337      "range end acrossing the unconditinal jmp.");1338}1339 1340void PerfScriptReader::parsePerfTraces() {1341  // Parse perf traces and do aggregation.1342  parseAndAggregateTrace();1343  if (Binary->isKernel() && !Binary->getIsLoadedByMMap()) {1344    exitWithError(1345        "Kernel is requested, but no kernel is found in mmap events.");1346  }1347 1348  emitWarningSummary(NumLeafExternalFrame, NumTotalSample,1349                     "of samples have leaf external frame in call stack.");1350  emitWarningSummary(NumLeadingOutgoingLBR, NumTotalSample,1351                     "of samples have leading external LBR.");1352 1353  // Generate unsymbolized profile.1354  warnTruncatedStack();1355  warnInvalidRange();1356  generateUnsymbolizedProfile();1357  AggregatedSamples.clear();1358 1359  if (SkipSymbolization)1360    writeUnsymbolizedProfile(OutputFilename);1361}1362 1363SmallVector<CleanupInstaller, 2> PerfScriptReader::TempFileCleanups;1364 1365} // end namespace sampleprof1366} // end namespace llvm1367