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1//===-- SourcePrinter.cpp -  source interleaving utilities ----------------===//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//9// This file implements the LiveElementPrinter and SourcePrinter classes to10// keep track of DWARF info as the current address is updated, and print out the11// source file line and variable or inlined function liveness as needed.12//13//===----------------------------------------------------------------------===//14 15#include "SourcePrinter.h"16#include "llvm-objdump.h"17#include "llvm/ADT/SmallSet.h"18#include "llvm/DebugInfo/DWARF/DWARFExpressionPrinter.h"19#include "llvm/DebugInfo/DWARF/LowLevel/DWARFExpression.h"20#include "llvm/Demangle/Demangle.h"21#include "llvm/Support/FormatVariadic.h"22 23#define DEBUG_TYPE "objdump"24 25namespace llvm {26namespace objdump {27 28bool InlinedFunction::liveAtAddress(object::SectionedAddress Addr) const {29  if (!Range.valid())30    return false;31 32  return Range.LowPC <= Addr.Address && Range.HighPC > Addr.Address;33}34 35void InlinedFunction::print(raw_ostream &OS, const MCRegisterInfo &MRI) const {36  const char *MangledCallerName = FuncDie.getName(DINameKind::LinkageName);37  if (!MangledCallerName)38    return;39 40  if (Demangle)41    OS << "inlined into " << demangle(MangledCallerName);42  else43    OS << "inlined into " << MangledCallerName;44}45 46void InlinedFunction::dump(raw_ostream &OS) const {47  OS << Name << " @ " << Range << ": ";48}49 50void InlinedFunction::printElementLine(raw_ostream &OS,51                                       object::SectionedAddress Addr,52                                       bool IsEnd) const {53  uint32_t CallFile, CallLine, CallColumn, CallDiscriminator;54  InlinedFuncDie.getCallerFrame(CallFile, CallLine, CallColumn,55                                CallDiscriminator);56  const DWARFDebugLine::LineTable *LineTable =57      Unit->getContext().getLineTableForUnit(Unit);58  std::string FileName;59  if (!LineTable->hasFileAtIndex(CallFile))60    return;61  if (!LineTable->getFileNameByIndex(62          CallFile, Unit->getCompilationDir(),63          DILineInfoSpecifier::FileLineInfoKind::AbsoluteFilePath, FileName))64    return;65 66  if (FileName.empty())67    return;68 69  const char *MangledCallerName = FuncDie.getName(DINameKind::LinkageName);70  if (!MangledCallerName)71    return;72 73  std::string CallerName = MangledCallerName;74  std::string CalleeName = Name;75  if (Demangle) {76    CallerName = demangle(MangledCallerName);77    CalleeName = demangle(Name);78  }79 80  OS << "; " << FileName << ":" << CallLine << ":" << CallColumn << ": ";81  if (IsEnd)82    OS << "end of ";83  OS << CalleeName << " inlined into " << CallerName << "\n";84}85 86bool LiveVariable::liveAtAddress(object::SectionedAddress Addr) const {87  if (LocExpr.Range == std::nullopt)88    return false;89  return LocExpr.Range->SectionIndex == Addr.SectionIndex &&90         LocExpr.Range->LowPC <= Addr.Address &&91         LocExpr.Range->HighPC > Addr.Address;92}93 94void LiveVariable::print(raw_ostream &OS, const MCRegisterInfo &MRI) const {95  DataExtractor Data({LocExpr.Expr.data(), LocExpr.Expr.size()},96                     Unit->getContext().isLittleEndian(), 0);97  DWARFExpression Expression(Data, Unit->getAddressByteSize());98 99  auto GetRegName = [&MRI, &OS](uint64_t DwarfRegNum, bool IsEH) -> StringRef {100    if (std::optional<MCRegister> LLVMRegNum =101            MRI.getLLVMRegNum(DwarfRegNum, IsEH))102      if (const char *RegName = MRI.getName(*LLVMRegNum))103        return StringRef(RegName);104    OS << "<unknown register " << DwarfRegNum << ">";105    return {};106  };107 108  printDwarfExpressionCompact(&Expression, OS, GetRegName);109}110 111void LiveVariable::dump(raw_ostream &OS) const {112  OS << Name << " @ " << LocExpr.Range << ": ";113}114 115void LiveElementPrinter::addInlinedFunction(DWARFDie FuncDie,116                                            DWARFDie InlinedFuncDie) {117  uint64_t FuncLowPC, FuncHighPC, SectionIndex;118  if (!InlinedFuncDie.getLowAndHighPC(FuncLowPC, FuncHighPC, SectionIndex))119    return;120 121  DWARFUnit *U = InlinedFuncDie.getDwarfUnit();122  const char *InlinedFuncName = InlinedFuncDie.getName(DINameKind::LinkageName);123  DWARFAddressRange Range{FuncLowPC, FuncHighPC, SectionIndex};124  // Add the new element to the main vector.125  LiveElements.emplace_back(std::make_unique<InlinedFunction>(126      InlinedFuncName, U, FuncDie, InlinedFuncDie, Range));127 128  LiveElement *LE = LiveElements.back().get();129  // Map the element's low address (LowPC) to its pointer for fast range start130  // lookup.131  LiveElementsByAddress[FuncLowPC].push_back(LE);132  // Map the element's high address (HighPC) to its pointer for fast range end133  // lookup.134  LiveElementsByEndAddress[FuncHighPC].push_back(LE);135  // Map the pointer to its DWARF discovery index for deterministic136  // ordering.137  ElementPtrToIndex[LE] = LiveElements.size() - 1;138}139 140/// Registers the most recently added LiveVariable into all data structures.141void LiveElementPrinter::registerNewVariable() {142  assert(143      !LiveElements.empty() &&144      "registerNewVariable called before element was added to LiveElements.");145  LiveVariable *CurrentVar =146      static_cast<LiveVariable *>(LiveElements.back().get());147  assert(ElementPtrToIndex.count(CurrentVar) == 0 &&148         "Element already registered!");149 150  // Map from a LiveElement pointer to its index in the LiveElements.151  ElementPtrToIndex[CurrentVar] = LiveElements.size() - 1;152 153  if (const std::optional<DWARFAddressRange> &Range =154          CurrentVar->getLocExpr().Range) {155    // Add the variable to address-based maps.156    LiveElementsByAddress[Range->LowPC].push_back(CurrentVar);157    LiveElementsByEndAddress[Range->HighPC].push_back(CurrentVar);158  }159}160 161void LiveElementPrinter::addVariable(DWARFDie FuncDie, DWARFDie VarDie) {162  uint64_t FuncLowPC, FuncHighPC, SectionIndex;163  FuncDie.getLowAndHighPC(FuncLowPC, FuncHighPC, SectionIndex);164  const char *VarName = VarDie.getName(DINameKind::ShortName);165  DWARFUnit *U = VarDie.getDwarfUnit();166 167  Expected<DWARFLocationExpressionsVector> Locs =168      VarDie.getLocations(dwarf::DW_AT_location);169  if (!Locs) {170    // If the variable doesn't have any locations, just ignore it. We don't171    // report an error or warning here as that could be noisy on optimised172    // code.173    consumeError(Locs.takeError());174    return;175  }176 177  for (const DWARFLocationExpression &LocExpr : *Locs) {178    if (LocExpr.Range) {179      LiveElements.emplace_back(180          std::make_unique<LiveVariable>(LocExpr, VarName, U, FuncDie));181    } else {182      // If the LocExpr does not have an associated range, it is valid for183      // the whole of the function.184      // TODO: technically it is not valid for any range covered by another185      // LocExpr, does that happen in reality?186      DWARFLocationExpression WholeFuncExpr{187          DWARFAddressRange(FuncLowPC, FuncHighPC, SectionIndex), LocExpr.Expr};188      LiveElements.emplace_back(189          std::make_unique<LiveVariable>(WholeFuncExpr, VarName, U, FuncDie));190    }191 192    // Register the new variable with all data structures.193    registerNewVariable();194  }195}196 197void LiveElementPrinter::addFunction(DWARFDie D) {198  for (const DWARFDie &Child : D.children()) {199    if (DbgVariables != DFDisabled &&200        (Child.getTag() == dwarf::DW_TAG_variable ||201         Child.getTag() == dwarf::DW_TAG_formal_parameter)) {202      addVariable(D, Child);203    } else if (DbgInlinedFunctions != DFDisabled &&204               Child.getTag() == dwarf::DW_TAG_inlined_subroutine) {205      addInlinedFunction(D, Child);206      addFunction(Child);207    } else208      addFunction(Child);209  }210}211 212// Get the column number (in characters) at which the first live element213// line should be printed.214unsigned LiveElementPrinter::getIndentLevel() const {215  return DbgIndent + getInstStartColumn(STI);216}217 218// Indent to the first live-range column to the right of the currently219// printed line, and return the index of that column.220// TODO: formatted_raw_ostream uses "column" to mean a number of characters221// since the last \n, and we use it to mean the number of slots in which we222// put live element lines. Pick a less overloaded word.223unsigned LiveElementPrinter::moveToFirstVarColumn(formatted_raw_ostream &OS) {224  // Logical column number: column zero is the first column we print in, each225  // logical column is 2 physical columns wide.226  unsigned FirstUnprintedLogicalColumn =227      std::max((int)(OS.getColumn() - getIndentLevel() + 1) / 2, 0);228  // Physical column number: the actual column number in characters, with229  // zero being the left-most side of the screen.230  unsigned FirstUnprintedPhysicalColumn =231      getIndentLevel() + FirstUnprintedLogicalColumn * 2;232 233  if (FirstUnprintedPhysicalColumn > OS.getColumn())234    OS.PadToColumn(FirstUnprintedPhysicalColumn);235 236  return FirstUnprintedLogicalColumn;237}238 239unsigned LiveElementPrinter::getOrCreateColumn(unsigned ElementIdx) {240  // Check if the element already has an assigned column.241  auto it = ElementToColumn.find(ElementIdx);242  if (it != ElementToColumn.end())243    return it->second;244 245  unsigned ColIdx;246  if (!FreeCols.empty()) {247    // Get the smallest available index from the set.248    ColIdx = *FreeCols.begin();249    // Remove the index from the set.250    FreeCols.erase(FreeCols.begin());251  } else {252    // No free columns, so create a new one.253    ColIdx = ActiveCols.size();254    ActiveCols.emplace_back();255  }256 257  // Assign the element to the column and update the map.258  ElementToColumn[ElementIdx] = ColIdx;259  ActiveCols[ColIdx].ElementIdx = ElementIdx;260  return ColIdx;261}262 263void LiveElementPrinter::freeColumn(unsigned ColIdx) {264  unsigned ElementIdx = ActiveCols[ColIdx].ElementIdx;265 266  // Clear the column's data.267  ActiveCols[ColIdx].clear();268 269  // Remove the element's entry from the map and add the column to the free270  // list.271  ElementToColumn.erase(ElementIdx);272  FreeCols.insert(ColIdx);273}274 275std::vector<unsigned>276LiveElementPrinter::getSortedActiveElementIndices() const {277  // Get all element indices that currently have an assigned column.278  std::vector<unsigned> Indices;279  for (const auto &Pair : ElementToColumn)280    Indices.push_back(Pair.first);281 282  // Sort by the DWARF discovery order.283  llvm::stable_sort(Indices);284  return Indices;285}286 287void LiveElementPrinter::dump() const {288  for (const std::unique_ptr<LiveElement> &LE : LiveElements) {289    LE->dump(dbgs());290    LE->print(dbgs(), MRI);291    dbgs() << "\n";292  }293}294 295void LiveElementPrinter::addCompileUnit(DWARFDie D) {296  if (D.getTag() == dwarf::DW_TAG_subprogram)297    addFunction(D);298  else299    for (const DWARFDie &Child : D.children())300      addFunction(Child);301}302 303/// Update to match the state of the instruction between ThisAddr and304/// NextAddr. In the common case, any live range active at ThisAddr is305/// live-in to the instruction, and any live range active at NextAddr is306/// live-out of the instruction. If IncludeDefinedVars is false, then live307/// ranges starting at NextAddr will be ignored.308void LiveElementPrinter::update(object::SectionedAddress ThisAddr,309                                object::SectionedAddress NextAddr,310                                bool IncludeDefinedVars) {311  // Exit early if only printing function limits.312  if (DbgInlinedFunctions == DFLimitsOnly)313    return;314 315  // Free columns identified in the previous cycle.316  for (unsigned ColIdx : ColumnsToFreeNextCycle)317    freeColumn(ColIdx);318  ColumnsToFreeNextCycle.clear();319 320  // Update status of active columns and collect those to free next cycle.321  for (unsigned ColIdx = 0, End = ActiveCols.size(); ColIdx < End; ++ColIdx) {322    if (!ActiveCols[ColIdx].isActive())323      continue;324 325    const std::unique_ptr<LiveElement> &LE =326        LiveElements[ActiveCols[ColIdx].ElementIdx];327    ActiveCols[ColIdx].LiveIn = LE->liveAtAddress(ThisAddr);328    ActiveCols[ColIdx].LiveOut = LE->liveAtAddress(NextAddr);329 330    LLVM_DEBUG({331      std::string Name = Demangle ? demangle(LE->getName()) : LE->getName();332      dbgs() << "pass 1, " << ThisAddr.Address << "-" << NextAddr.Address333             << ", " << Name << ", Col " << ColIdx334             << ": LiveIn=" << ActiveCols[ColIdx].LiveIn335             << ", LiveOut=" << ActiveCols[ColIdx].LiveOut << "\n";336    });337 338    // If element is fully dead, deactivate column immediately.339    if (!ActiveCols[ColIdx].LiveIn && !ActiveCols[ColIdx].LiveOut) {340      ActiveCols[ColIdx].ElementIdx = Column::NullElementIdx;341      continue;342    }343 344    // Mark for cleanup in the next cycle if range ends here.345    if (ActiveCols[ColIdx].LiveIn && !ActiveCols[ColIdx].LiveOut)346      ColumnsToFreeNextCycle.push_back(ColIdx);347  }348 349  // Next, look for variables which don't already have a column, but which350  // are now live (those starting at ThisAddr or NextAddr).351  if (IncludeDefinedVars) {352    // Collect all elements starting at ThisAddr and NextAddr.353    std::vector<std::pair<unsigned, LiveElement *>> NewLiveElements;354    auto CollectNewElements = [&](const auto &It) {355      if (It == LiveElementsByAddress.end())356        return;357 358      const std::vector<LiveElement *> &ElementList = It->second;359      for (LiveElement *LE : ElementList) {360        auto IndexIt = ElementPtrToIndex.find(LE);361        assert(IndexIt != ElementPtrToIndex.end() &&362               "LiveElement in address map but missing from index map!");363 364        // Get the element index for sorting and column management.365        unsigned ElementIdx = IndexIt->second;366        // Skip elements that already have a column.367        if (ElementToColumn.count(ElementIdx))368          continue;369 370        bool LiveIn = LE->liveAtAddress(ThisAddr);371        bool LiveOut = LE->liveAtAddress(NextAddr);372        if (!LiveIn && !LiveOut)373          continue;374 375        NewLiveElements.emplace_back(ElementIdx, LE);376      }377    };378 379    // Collect elements starting at ThisAddr.380    CollectNewElements(LiveElementsByAddress.find(ThisAddr.Address));381    // Collect elements starting at NextAddr (the address immediately382    // following the instruction).383    CollectNewElements(LiveElementsByAddress.find(NextAddr.Address));384    // Sort elements by DWARF discovery order for deterministic column385    // assignment.386    llvm::stable_sort(NewLiveElements, [](const auto &A, const auto &B) {387      return A.first < B.first;388    });389 390    // Assign columns in deterministic order.391    for (const auto &ElementPair : NewLiveElements) {392      unsigned ElementIdx = ElementPair.first;393      // Skip if element was already added from the first range.394      if (ElementToColumn.count(ElementIdx))395        continue;396 397      LiveElement *LE = ElementPair.second;398      bool LiveIn = LE->liveAtAddress(ThisAddr);399      bool LiveOut = LE->liveAtAddress(NextAddr);400 401      // Assign or create a column.402      unsigned ColIdx = getOrCreateColumn(ElementIdx);403      LLVM_DEBUG({404        std::string Name = Demangle ? demangle(LE->getName()) : LE->getName();405        dbgs() << "pass 2, " << ThisAddr.Address << "-" << NextAddr.Address406               << ", " << Name << ", Col " << ColIdx << ": LiveIn=" << LiveIn407               << ", LiveOut=" << LiveOut << "\n";408      });409 410      ActiveCols[ColIdx].LiveIn = LiveIn;411      ActiveCols[ColIdx].LiveOut = LiveOut;412      ActiveCols[ColIdx].MustDrawLabel = true;413 414      // Mark for cleanup next cycle if range ends here.415      if (ActiveCols[ColIdx].LiveIn && !ActiveCols[ColIdx].LiveOut)416        ColumnsToFreeNextCycle.push_back(ColIdx);417    }418  }419}420 421enum class LineChar {422  RangeStart,423  RangeMid,424  RangeEnd,425  LabelVert,426  LabelCornerNew,427  LabelCornerActive,428  LabelHoriz,429};430const char *LiveElementPrinter::getLineChar(LineChar C) const {431  bool IsASCII = DbgVariables == DFASCII || DbgInlinedFunctions == DFASCII;432  switch (C) {433  case LineChar::RangeStart:434    return IsASCII ? "^" : (const char *)u8"\u2548";435  case LineChar::RangeMid:436    return IsASCII ? "|" : (const char *)u8"\u2503";437  case LineChar::RangeEnd:438    return IsASCII ? "v" : (const char *)u8"\u253b";439  case LineChar::LabelVert:440    return IsASCII ? "|" : (const char *)u8"\u2502";441  case LineChar::LabelCornerNew:442    return IsASCII ? "/" : (const char *)u8"\u250c";443  case LineChar::LabelCornerActive:444    return IsASCII ? "|" : (const char *)u8"\u2520";445  case LineChar::LabelHoriz:446    return IsASCII ? "-" : (const char *)u8"\u2500";447  }448  llvm_unreachable("Unhandled LineChar enum");449}450 451/// Print live ranges to the right of an existing line. This assumes the452/// line is not an instruction, so doesn't start or end any live ranges, so453/// we only need to print active ranges or empty columns. If AfterInst is454/// true, this is being printed after the last instruction fed to update(),455/// otherwise this is being printed before it.456void LiveElementPrinter::printAfterOtherLine(formatted_raw_ostream &OS,457                                             bool AfterInst) {458  if (ActiveCols.size()) {459    unsigned FirstUnprintedColumn = moveToFirstVarColumn(OS);460    for (size_t ColIdx = FirstUnprintedColumn, End = ActiveCols.size();461         ColIdx < End; ++ColIdx) {462      if (ActiveCols[ColIdx].isActive()) {463        if ((AfterInst && ActiveCols[ColIdx].LiveOut) ||464            (!AfterInst && ActiveCols[ColIdx].LiveIn))465          OS << getLineChar(LineChar::RangeMid);466        else if (!AfterInst && ActiveCols[ColIdx].LiveOut)467          OS << getLineChar(LineChar::LabelVert);468        else469          OS << " ";470      }471      OS << " ";472    }473  }474  OS << "\n";475}476 477/// Print any live element range info needed to the right of a478/// non-instruction line of disassembly. This is where we print the element479/// names and expressions, with thin line-drawing characters connecting them480/// to the live range which starts at the next instruction. If MustPrint is481/// true, we have to print at least one line (with the continuation of any482/// already-active live ranges) because something has already been printed483/// earlier on this line.484void LiveElementPrinter::printBetweenInsts(formatted_raw_ostream &OS,485                                           bool MustPrint) {486  bool PrintedSomething = false;487  // Get all active elements, sorted by discovery order.488  std::vector<unsigned> SortedElementIndices = getSortedActiveElementIndices();489  // The outer loop iterates over the deterministic DWARF discovery order.490  for (unsigned ElementIdx : SortedElementIndices) {491    // Look up the physical column index (ColIdx) assigned to this492    // element. We use .at() because we are certain the element is active.493    unsigned ColIdx = ElementToColumn.at(ElementIdx);494    if (ActiveCols[ColIdx].isActive() && ActiveCols[ColIdx].MustDrawLabel) {495      // First we need to print the live range markers for any active496      // columns to the left of this one.497      OS.PadToColumn(getIndentLevel());498      for (unsigned ColIdx2 = 0; ColIdx2 < ColIdx; ++ColIdx2) {499        if (ActiveCols[ColIdx2].isActive()) {500          if (ActiveCols[ColIdx2].MustDrawLabel && !ActiveCols[ColIdx2].LiveIn)501            OS << getLineChar(LineChar::LabelVert) << " ";502          else503            OS << getLineChar(LineChar::RangeMid) << " ";504        } else505          OS << "  ";506      }507 508      const std::unique_ptr<LiveElement> &LE = LiveElements[ElementIdx];509      // Then print the variable name and location of the new live range,510      // with box drawing characters joining it to the live range line.511      OS << getLineChar(ActiveCols[ColIdx].LiveIn ? LineChar::LabelCornerActive512                                                  : LineChar::LabelCornerNew)513         << getLineChar(LineChar::LabelHoriz) << " ";514 515      std::string Name = Demangle ? demangle(LE->getName()) : LE->getName();516      WithColor(OS, raw_ostream::GREEN) << Name;517      OS << " = ";518      {519        WithColor ExprColor(OS, raw_ostream::CYAN);520        LE->print(OS, MRI);521      }522 523      // If there are any columns to the right of the expression we just524      // printed, then continue their live range lines.525      unsigned FirstUnprintedColumn = moveToFirstVarColumn(OS);526      for (unsigned ColIdx2 = FirstUnprintedColumn, End = ActiveCols.size();527           ColIdx2 < End; ++ColIdx2) {528        if (ActiveCols[ColIdx2].isActive() && ActiveCols[ColIdx2].LiveIn)529          OS << getLineChar(LineChar::RangeMid) << " ";530        else531          OS << "  ";532      }533 534      OS << "\n";535      PrintedSomething = true;536    }537  }538 539  for (unsigned ColIdx = 0, End = ActiveCols.size(); ColIdx < End; ++ColIdx)540    if (ActiveCols[ColIdx].isActive())541      ActiveCols[ColIdx].MustDrawLabel = false;542 543  // If we must print something (because we printed a line/column number),544  // but don't have any new variables to print, then print a line which545  // just continues any existing live ranges.546  if (MustPrint && !PrintedSomething)547    printAfterOtherLine(OS, false);548}549 550/// Print the live element ranges to the right of a disassembled instruction.551void LiveElementPrinter::printAfterInst(formatted_raw_ostream &OS) {552  if (!ActiveCols.size())553    return;554  unsigned FirstUnprintedColumn = moveToFirstVarColumn(OS);555  for (unsigned ColIdx = FirstUnprintedColumn, End = ActiveCols.size();556       ColIdx < End; ++ColIdx) {557    if (!ActiveCols[ColIdx].isActive())558      OS << "  ";559    else if (ActiveCols[ColIdx].LiveIn && ActiveCols[ColIdx].LiveOut)560      OS << getLineChar(LineChar::RangeMid) << " ";561    else if (ActiveCols[ColIdx].LiveOut)562      OS << getLineChar(LineChar::RangeStart) << " ";563    else if (ActiveCols[ColIdx].LiveIn)564      OS << getLineChar(LineChar::RangeEnd) << " ";565    else566      llvm_unreachable("var must be live in or out!");567  }568}569 570void LiveElementPrinter::printBoundaryLine(formatted_raw_ostream &OS,571                                           object::SectionedAddress Addr,572                                           bool IsEnd) {573  // Only print the start/end line for inlined functions if DFLimitsOnly is574  // enabled.575  if (DbgInlinedFunctions != DFLimitsOnly)576    return;577 578  // Select the appropriate map based on whether we are checking the start579  // (LowPC) or end (HighPC) address.580  const auto &AddressMap =581      IsEnd ? LiveElementsByEndAddress : LiveElementsByAddress;582 583  // Use the map to find all elements that start/end at the given address.584  std::vector<unsigned> ElementIndices;585  auto It = AddressMap.find(Addr.Address);586  if (It != AddressMap.end()) {587    for (LiveElement *LE : It->second) {588      // Look up the element index from the pointer.589      auto IndexIt = ElementPtrToIndex.find(LE);590      assert(IndexIt != ElementPtrToIndex.end() &&591             "LiveElement found in address map but missing index!");592      ElementIndices.push_back(IndexIt->second);593    }594  }595 596  // Sort the indices to ensure deterministic output order (by DWARF discovery597  // order).598  llvm::stable_sort(ElementIndices);599 600  for (unsigned ElementIdx : ElementIndices) {601    LiveElement *LE = LiveElements[ElementIdx].get();602    LE->printElementLine(OS, Addr, IsEnd);603  }604}605 606bool SourcePrinter::cacheSource(const DILineInfo &LineInfo) {607  std::unique_ptr<MemoryBuffer> Buffer;608  if (LineInfo.Source) {609    Buffer = MemoryBuffer::getMemBuffer(*LineInfo.Source);610  } else {611    auto BufferOrError =612        MemoryBuffer::getFile(LineInfo.FileName, /*IsText=*/true);613    if (!BufferOrError) {614      if (MissingSources.insert(LineInfo.FileName).second)615        reportWarning("failed to find source " + LineInfo.FileName,616                      Obj->getFileName());617      return false;618    }619    Buffer = std::move(*BufferOrError);620  }621  // Chomp the file to get lines622  const char *BufferStart = Buffer->getBufferStart(),623             *BufferEnd = Buffer->getBufferEnd();624  std::vector<StringRef> &Lines = LineCache[LineInfo.FileName];625  const char *Start = BufferStart;626  for (const char *I = BufferStart; I != BufferEnd; ++I)627    if (*I == '\n') {628      Lines.emplace_back(Start, I - Start - (BufferStart < I && I[-1] == '\r'));629      Start = I + 1;630    }631  if (Start < BufferEnd)632    Lines.emplace_back(Start, BufferEnd - Start);633  SourceCache[LineInfo.FileName] = std::move(Buffer);634  return true;635}636 637void SourcePrinter::printSourceLine(formatted_raw_ostream &OS,638                                    object::SectionedAddress Address,639                                    StringRef ObjectFilename,640                                    LiveElementPrinter &LEP,641                                    StringRef Delimiter) {642  if (!Symbolizer)643    return;644 645  DILineInfo LineInfo = DILineInfo();646  Expected<DILineInfo> ExpectedLineInfo =647      Symbolizer->symbolizeCode(*Obj, Address);648  if (ExpectedLineInfo) {649    LineInfo = *ExpectedLineInfo;650  } else if (!WarnedInvalidDebugInfo) {651    WarnedInvalidDebugInfo = true;652    // TODO Untested.653    reportWarning("failed to parse debug information: " +654                      toString(ExpectedLineInfo.takeError()),655                  ObjectFilename);656  }657 658  if (!objdump::Prefix.empty() &&659      sys::path::is_absolute_gnu(LineInfo.FileName)) {660    // FileName has at least one character since is_absolute_gnu is false for661    // an empty string.662    assert(!LineInfo.FileName.empty());663    if (PrefixStrip > 0) {664      uint32_t Level = 0;665      auto StrippedNameStart = LineInfo.FileName.begin();666 667      // Path.h iterator skips extra separators. Therefore it cannot be used668      // here to keep compatibility with GNU Objdump.669      for (auto Pos = StrippedNameStart + 1, End = LineInfo.FileName.end();670           Pos != End && Level < PrefixStrip; ++Pos) {671        if (sys::path::is_separator(*Pos)) {672          StrippedNameStart = Pos;673          ++Level;674        }675      }676 677      LineInfo.FileName =678          std::string(StrippedNameStart, LineInfo.FileName.end());679    }680 681    SmallString<128> FilePath;682    sys::path::append(FilePath, Prefix, LineInfo.FileName);683 684    LineInfo.FileName = std::string(FilePath);685  }686 687  if (PrintLines)688    printLines(OS, Address, LineInfo, Delimiter, LEP);689  if (PrintSource)690    printSources(OS, LineInfo, ObjectFilename, Delimiter, LEP);691  OldLineInfo = LineInfo;692}693 694void SourcePrinter::printLines(formatted_raw_ostream &OS,695                               object::SectionedAddress Address,696                               const DILineInfo &LineInfo, StringRef Delimiter,697                               LiveElementPrinter &LEP) {698  bool PrintFunctionName = LineInfo.FunctionName != DILineInfo::BadString &&699                           LineInfo.FunctionName != OldLineInfo.FunctionName;700  if (PrintFunctionName) {701    OS << Delimiter << LineInfo.FunctionName;702    // If demangling is successful, FunctionName will end with "()". Print it703    // only if demangling did not run or was unsuccessful.704    if (!StringRef(LineInfo.FunctionName).ends_with("()"))705      OS << "()";706    OS << ":\n";707  }708  if (LineInfo.FileName != DILineInfo::BadString && LineInfo.Line != 0 &&709      (OldLineInfo.Line != LineInfo.Line ||710       OldLineInfo.FileName != LineInfo.FileName || PrintFunctionName)) {711    OS << Delimiter << LineInfo.FileName << ":" << LineInfo.Line;712    LEP.printBetweenInsts(OS, true);713  }714}715 716// Get the source line text for LineInfo:717// - use LineInfo::LineSource if available;718// - use LineCache if LineInfo::Source otherwise.719StringRef SourcePrinter::getLine(const DILineInfo &LineInfo,720                                 StringRef ObjectFilename) {721  if (LineInfo.LineSource)722    return LineInfo.LineSource.value();723 724  if (SourceCache.find(LineInfo.FileName) == SourceCache.end())725    if (!cacheSource(LineInfo))726      return {};727 728  auto LineBuffer = LineCache.find(LineInfo.FileName);729  if (LineBuffer == LineCache.end())730    return {};731 732  if (LineInfo.Line > LineBuffer->second.size()) {733    reportWarning(734        formatv("debug info line number {0} exceeds the number of lines in {1}",735                LineInfo.Line, LineInfo.FileName),736        ObjectFilename);737    return {};738  }739 740  // Vector begins at 0, line numbers are non-zero741  return LineBuffer->second[LineInfo.Line - 1];742}743 744void SourcePrinter::printSources(formatted_raw_ostream &OS,745                                 const DILineInfo &LineInfo,746                                 StringRef ObjectFilename, StringRef Delimiter,747                                 LiveElementPrinter &LEP) {748  if (LineInfo.FileName == DILineInfo::BadString || LineInfo.Line == 0 ||749      (OldLineInfo.Line == LineInfo.Line &&750       OldLineInfo.FileName == LineInfo.FileName))751    return;752 753  StringRef Line = getLine(LineInfo, ObjectFilename);754  if (!Line.empty()) {755    OS << Delimiter << Line;756    LEP.printBetweenInsts(OS, true);757  }758}759 760SourcePrinter::SourcePrinter(const object::ObjectFile *Obj,761                             StringRef DefaultArch)762    : Obj(Obj) {763  symbolize::LLVMSymbolizer::Options SymbolizerOpts;764  SymbolizerOpts.PrintFunctions =765      DILineInfoSpecifier::FunctionNameKind::LinkageName;766  SymbolizerOpts.Demangle = Demangle;767  SymbolizerOpts.DefaultArch = std::string(DefaultArch);768  Symbolizer.reset(new symbolize::LLVMSymbolizer(SymbolizerOpts));769}770 771} // namespace objdump772} // namespace llvm773