LLVM  9.0.0svn
DWARFUnit.cpp
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1 //===- DWARFUnit.cpp ------------------------------------------------------===//
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 
10 #include "llvm/ADT/SmallString.h"
11 #include "llvm/ADT/StringRef.h"
22 #include "llvm/Support/Errc.h"
23 #include "llvm/Support/Path.h"
24 #include "llvm/Support/WithColor.h"
25 #include <algorithm>
26 #include <cassert>
27 #include <cstddef>
28 #include <cstdint>
29 #include <cstdio>
30 #include <utility>
31 #include <vector>
32 
33 using namespace llvm;
34 using namespace dwarf;
35 
37  const DWARFSection &Section,
39  const DWARFObject &D = C.getDWARFObj();
40  addUnitsImpl(C, D, Section, C.getDebugAbbrev(), &D.getRangeSection(),
43  D.getLineSection(), D.isLittleEndian(), false, false,
44  SectionKind);
45 }
46 
48  const DWARFSection &DWOSection,
50  bool Lazy) {
51  const DWARFObject &D = C.getDWARFObj();
52  addUnitsImpl(C, D, DWOSection, C.getDebugAbbrevDWO(), &D.getRangeDWOSection(),
55  D.getLineDWOSection(), C.isLittleEndian(), true, Lazy,
56  SectionKind);
57 }
58 
59 void DWARFUnitVector::addUnitsImpl(
61  const DWARFDebugAbbrev *DA, const DWARFSection *RS,
62  const DWARFSection *LocSection, StringRef SS, const DWARFSection &SOS,
63  const DWARFSection *AOS, const DWARFSection &LS, bool LE, bool IsDWO,
64  bool Lazy, DWARFSectionKind SectionKind) {
65  DWARFDataExtractor Data(Obj, Section, LE, 0);
66  // Lazy initialization of Parser, now that we have all section info.
67  if (!Parser) {
68  Parser = [=, &Context, &Obj, &Section, &SOS,
69  &LS](uint32_t Offset, DWARFSectionKind SectionKind,
70  const DWARFSection *CurSection,
71  const DWARFUnitIndex::Entry *IndexEntry)
72  -> std::unique_ptr<DWARFUnit> {
73  const DWARFSection &InfoSection = CurSection ? *CurSection : Section;
74  DWARFDataExtractor Data(Obj, InfoSection, LE, 0);
75  if (!Data.isValidOffset(Offset))
76  return nullptr;
77  const DWARFUnitIndex *Index = nullptr;
78  if (IsDWO)
79  Index = &getDWARFUnitIndex(Context, SectionKind);
80  DWARFUnitHeader Header;
81  if (!Header.extract(Context, Data, &Offset, SectionKind, Index,
82  IndexEntry))
83  return nullptr;
84  std::unique_ptr<DWARFUnit> U;
85  if (Header.isTypeUnit())
86  U = llvm::make_unique<DWARFTypeUnit>(Context, InfoSection, Header, DA,
87  RS, LocSection, SS, SOS, AOS, LS,
88  LE, IsDWO, *this);
89  else
90  U = llvm::make_unique<DWARFCompileUnit>(Context, InfoSection, Header,
91  DA, RS, LocSection, SS, SOS,
92  AOS, LS, LE, IsDWO, *this);
93  return U;
94  };
95  }
96  if (Lazy)
97  return;
98  // Find a reasonable insertion point within the vector. We skip over
99  // (a) units from a different section, (b) units from the same section
100  // but with lower offset-within-section. This keeps units in order
101  // within a section, although not necessarily within the object file,
102  // even if we do lazy parsing.
103  auto I = this->begin();
104  uint32_t Offset = 0;
105  while (Data.isValidOffset(Offset)) {
106  if (I != this->end() &&
107  (&(*I)->getInfoSection() != &Section || (*I)->getOffset() == Offset)) {
108  ++I;
109  continue;
110  }
111  auto U = Parser(Offset, SectionKind, &Section, nullptr);
112  // If parsing failed, we're done with this section.
113  if (!U)
114  break;
115  Offset = U->getNextUnitOffset();
116  I = std::next(this->insert(I, std::move(U)));
117  }
118 }
119 
120 DWARFUnit *DWARFUnitVector::addUnit(std::unique_ptr<DWARFUnit> Unit) {
121  auto I = std::upper_bound(begin(), end(), Unit,
122  [](const std::unique_ptr<DWARFUnit> &LHS,
123  const std::unique_ptr<DWARFUnit> &RHS) {
124  return LHS->getOffset() < RHS->getOffset();
125  });
126  return this->insert(I, std::move(Unit))->get();
127 }
128 
130  auto end = begin() + getNumInfoUnits();
131  auto *CU =
132  std::upper_bound(begin(), end, Offset,
133  [](uint32_t LHS, const std::unique_ptr<DWARFUnit> &RHS) {
134  return LHS < RHS->getNextUnitOffset();
135  });
136  if (CU != end && (*CU)->getOffset() <= Offset)
137  return CU->get();
138  return nullptr;
139 }
140 
141 DWARFUnit *
143  const auto *CUOff = E.getOffset(DW_SECT_INFO);
144  if (!CUOff)
145  return nullptr;
146 
147  auto Offset = CUOff->Offset;
148  auto end = begin() + getNumInfoUnits();
149 
150  auto *CU =
151  std::upper_bound(begin(), end, CUOff->Offset,
152  [](uint32_t LHS, const std::unique_ptr<DWARFUnit> &RHS) {
153  return LHS < RHS->getNextUnitOffset();
154  });
155  if (CU != end && (*CU)->getOffset() <= Offset)
156  return CU->get();
157 
158  if (!Parser)
159  return nullptr;
160 
161  auto U = Parser(Offset, DW_SECT_INFO, nullptr, &E);
162  if (!U)
163  U = nullptr;
164 
165  auto *NewCU = U.get();
166  this->insert(CU, std::move(U));
167  ++NumInfoUnits;
168  return NewCU;
169 }
170 
172  const DWARFUnitHeader &Header, const DWARFDebugAbbrev *DA,
173  const DWARFSection *RS, const DWARFSection *LocSection,
174  StringRef SS, const DWARFSection &SOS,
175  const DWARFSection *AOS, const DWARFSection &LS, bool LE,
176  bool IsDWO, const DWARFUnitVector &UnitVector)
177  : Context(DC), InfoSection(Section), Header(Header), Abbrev(DA),
178  RangeSection(RS), LocSection(LocSection), LineSection(LS),
179  StringSection(SS), StringOffsetSection(SOS), AddrOffsetSection(AOS),
180  isLittleEndian(LE), IsDWO(IsDWO), UnitVector(UnitVector) {
181  clear();
182  // For split DWARF we only need to keep track of the location list section's
183  // data (no relocations), and if we are reading a package file, we need to
184  // adjust the location list data based on the index entries.
185  if (IsDWO) {
186  LocSectionData = LocSection->Data;
187  if (auto *IndexEntry = Header.getIndexEntry())
188  if (const auto *C = IndexEntry->getOffset(DW_SECT_LOC))
189  LocSectionData = LocSectionData.substr(C->Offset, C->Length);
190  }
191 }
192 
193 DWARFUnit::~DWARFUnit() = default;
194 
196  return DWARFDataExtractor(Context.getDWARFObj(), InfoSection, isLittleEndian,
198 }
199 
202  if (IsDWO) {
203  auto R = Context.info_section_units();
204  auto I = R.begin();
205  // Surprising if a DWO file has more than one skeleton unit in it - this
206  // probably shouldn't be valid, but if a use case is found, here's where to
207  // support it (probably have to linearly search for the matching skeleton CU
208  // here)
209  if (I != R.end() && std::next(I) == R.end())
210  return (*I)->getAddrOffsetSectionItem(Index);
211  }
212  uint32_t Offset = AddrOffsetSectionBase + Index * getAddressByteSize();
213  if (AddrOffsetSection->Data.size() < Offset + getAddressByteSize())
214  return None;
215  DWARFDataExtractor DA(Context.getDWARFObj(), *AddrOffsetSection,
216  isLittleEndian, getAddressByteSize());
217  uint64_t Section;
218  uint64_t Address = DA.getRelocatedAddress(&Offset, &Section);
219  return {{Address, Section}};
220 }
221 
223  if (!StringOffsetsTableContribution)
224  return None;
225  unsigned ItemSize = getDwarfStringOffsetsByteSize();
226  uint32_t Offset = getStringOffsetsBase() + Index * ItemSize;
227  if (StringOffsetSection.Data.size() < Offset + ItemSize)
228  return None;
229  DWARFDataExtractor DA(Context.getDWARFObj(), StringOffsetSection,
230  isLittleEndian, 0);
231  return DA.getRelocatedValue(ItemSize, &Offset);
232 }
233 
235  const DWARFDataExtractor &debug_info,
236  uint32_t *offset_ptr,
238  const DWARFUnitIndex *Index,
239  const DWARFUnitIndex::Entry *Entry) {
240  Offset = *offset_ptr;
241  IndexEntry = Entry;
242  if (!IndexEntry && Index)
243  IndexEntry = Index->getFromOffset(*offset_ptr);
244  Length = debug_info.getU32(offset_ptr);
245  // FIXME: Support DWARF64.
246  unsigned SizeOfLength = 4;
248  FormParams.Version = debug_info.getU16(offset_ptr);
249  if (FormParams.Version >= 5) {
250  UnitType = debug_info.getU8(offset_ptr);
251  FormParams.AddrSize = debug_info.getU8(offset_ptr);
252  AbbrOffset = debug_info.getU32(offset_ptr);
253  } else {
254  AbbrOffset = debug_info.getRelocatedValue(4, offset_ptr);
255  FormParams.AddrSize = debug_info.getU8(offset_ptr);
256  // Fake a unit type based on the section type. This isn't perfect,
257  // but distinguishing compile and type units is generally enough.
258  if (SectionKind == DW_SECT_TYPES)
259  UnitType = DW_UT_type;
260  else
261  UnitType = DW_UT_compile;
262  }
263  if (IndexEntry) {
264  if (AbbrOffset)
265  return false;
266  auto *UnitContrib = IndexEntry->getOffset();
267  if (!UnitContrib || UnitContrib->Length != (Length + 4))
268  return false;
269  auto *AbbrEntry = IndexEntry->getOffset(DW_SECT_ABBREV);
270  if (!AbbrEntry)
271  return false;
272  AbbrOffset = AbbrEntry->Offset;
273  }
274  if (isTypeUnit()) {
275  TypeHash = debug_info.getU64(offset_ptr);
276  TypeOffset = debug_info.getU32(offset_ptr);
277  } else if (UnitType == DW_UT_split_compile || UnitType == DW_UT_skeleton)
278  DWOId = debug_info.getU64(offset_ptr);
279 
280  // Header fields all parsed, capture the size of this unit header.
281  assert(*offset_ptr - Offset <= 255 && "unexpected header size");
282  Size = uint8_t(*offset_ptr - Offset);
283 
284  // Type offset is unit-relative; should be after the header and before
285  // the end of the current unit.
286  bool TypeOffsetOK =
287  !isTypeUnit()
288  ? true
289  : TypeOffset >= Size && TypeOffset < getLength() + SizeOfLength;
290  bool LengthOK = debug_info.isValidOffset(getNextUnitOffset() - 1);
291  bool VersionOK = DWARFContext::isSupportedVersion(getVersion());
292  bool AddrSizeOK = getAddressByteSize() == 4 || getAddressByteSize() == 8;
293 
294  if (!LengthOK || !VersionOK || !AddrSizeOK || !TypeOffsetOK)
295  return false;
296 
297  // Keep track of the highest DWARF version we encounter across all units.
299  return true;
300 }
301 
302 // Parse the rangelist table header, including the optional array of offsets
303 // following it (DWARF v5 and later).
306  // TODO: Support DWARF64
307  // We are expected to be called with Offset 0 or pointing just past the table
308  // header, which is 12 bytes long for DWARF32.
309  if (Offset > 0) {
310  if (Offset < 12U)
311  return createStringError(errc::invalid_argument, "Did not detect a valid"
312  " range list table with base = 0x%" PRIu32,
313  Offset);
314  Offset -= 12U;
315  }
317  if (Error E = Table.extractHeaderAndOffsets(DA, &Offset))
318  return std::move(E);
319  return Table;
320 }
321 
323  DWARFDebugRangeList &RangeList) const {
324  // Require that compile unit is extracted.
325  assert(!DieArray.empty());
326  DWARFDataExtractor RangesData(Context.getDWARFObj(), *RangeSection,
327  isLittleEndian, getAddressByteSize());
328  uint32_t ActualRangeListOffset = RangeSectionBase + RangeListOffset;
329  return RangeList.extract(RangesData, &ActualRangeListOffset);
330 }
331 
333  Abbrevs = nullptr;
334  BaseAddr.reset();
335  RangeSectionBase = 0;
336  AddrOffsetSectionBase = 0;
337  clearDIEs(false);
338  DWO.reset();
339 }
340 
342  return dwarf::toString(getUnitDIE().find(DW_AT_comp_dir), nullptr);
343 }
344 
345 void DWARFUnit::extractDIEsToVector(
346  bool AppendCUDie, bool AppendNonCUDies,
347  std::vector<DWARFDebugInfoEntry> &Dies) const {
348  if (!AppendCUDie && !AppendNonCUDies)
349  return;
350 
351  // Set the offset to that of the first DIE and calculate the start of the
352  // next compilation unit header.
353  uint32_t DIEOffset = getOffset() + getHeaderSize();
354  uint32_t NextCUOffset = getNextUnitOffset();
356  DWARFDataExtractor DebugInfoData = getDebugInfoExtractor();
357  uint32_t Depth = 0;
358  bool IsCUDie = true;
359 
360  while (DIE.extractFast(*this, &DIEOffset, DebugInfoData, NextCUOffset,
361  Depth)) {
362  if (IsCUDie) {
363  if (AppendCUDie)
364  Dies.push_back(DIE);
365  if (!AppendNonCUDies)
366  break;
367  // The average bytes per DIE entry has been seen to be
368  // around 14-20 so let's pre-reserve the needed memory for
369  // our DIE entries accordingly.
370  Dies.reserve(Dies.size() + getDebugInfoSize() / 14);
371  IsCUDie = false;
372  } else {
373  Dies.push_back(DIE);
374  }
375 
376  if (const DWARFAbbreviationDeclaration *AbbrDecl =
378  // Normal DIE
379  if (AbbrDecl->hasChildren())
380  ++Depth;
381  } else {
382  // NULL DIE.
383  if (Depth > 0)
384  --Depth;
385  if (Depth == 0)
386  break; // We are done with this compile unit!
387  }
388  }
389 
390  // Give a little bit of info if we encounter corrupt DWARF (our offset
391  // should always terminate at or before the start of the next compilation
392  // unit header).
393  if (DIEOffset > NextCUOffset)
394  WithColor::warning() << format("DWARF compile unit extends beyond its "
395  "bounds cu 0x%8.8x at 0x%8.8x\n",
396  getOffset(), DIEOffset);
397 }
398 
399 size_t DWARFUnit::extractDIEsIfNeeded(bool CUDieOnly) {
400  if ((CUDieOnly && !DieArray.empty()) ||
401  DieArray.size() > 1)
402  return 0; // Already parsed.
403 
404  bool HasCUDie = !DieArray.empty();
405  extractDIEsToVector(!HasCUDie, !CUDieOnly, DieArray);
406 
407  if (DieArray.empty())
408  return 0;
409 
410  // If CU DIE was just parsed, copy several attribute values from it.
411  if (!HasCUDie) {
412  DWARFDie UnitDie = getUnitDIE();
413  if (Optional<uint64_t> DWOId = toUnsigned(UnitDie.find(DW_AT_GNU_dwo_id)))
414  Header.setDWOId(*DWOId);
415  if (!IsDWO) {
416  assert(AddrOffsetSectionBase == 0);
417  assert(RangeSectionBase == 0);
418  AddrOffsetSectionBase = toSectionOffset(UnitDie.find(DW_AT_addr_base), 0);
419  if (!AddrOffsetSectionBase)
420  AddrOffsetSectionBase =
421  toSectionOffset(UnitDie.find(DW_AT_GNU_addr_base), 0);
422  RangeSectionBase = toSectionOffset(UnitDie.find(DW_AT_rnglists_base), 0);
423  }
424 
425  // In general, in DWARF v5 and beyond we derive the start of the unit's
426  // contribution to the string offsets table from the unit DIE's
427  // DW_AT_str_offsets_base attribute. Split DWARF units do not use this
428  // attribute, so we assume that there is a contribution to the string
429  // offsets table starting at offset 0 of the debug_str_offsets.dwo section.
430  // In both cases we need to determine the format of the contribution,
431  // which may differ from the unit's format.
432  DWARFDataExtractor DA(Context.getDWARFObj(), StringOffsetSection,
433  isLittleEndian, 0);
434  if (IsDWO)
435  StringOffsetsTableContribution =
437  else if (getVersion() >= 5)
438  StringOffsetsTableContribution =
440 
441  // DWARF v5 uses the .debug_rnglists and .debug_rnglists.dwo sections to
442  // describe address ranges.
443  if (getVersion() >= 5) {
444  if (IsDWO)
446  else
448  toSectionOffset(UnitDie.find(DW_AT_rnglists_base), 0));
449  if (RangeSection->Data.size()) {
450  // Parse the range list table header. Individual range lists are
451  // extracted lazily.
452  DWARFDataExtractor RangesDA(Context.getDWARFObj(), *RangeSection,
453  isLittleEndian, 0);
454  if (auto TableOrError =
455  parseRngListTableHeader(RangesDA, RangeSectionBase))
456  RngListTable = TableOrError.get();
457  else
458  WithColor::error() << "parsing a range list table: "
459  << toString(TableOrError.takeError())
460  << '\n';
461 
462  // In a split dwarf unit, there is no DW_AT_rnglists_base attribute.
463  // Adjust RangeSectionBase to point past the table header.
464  if (IsDWO && RngListTable)
465  RangeSectionBase = RngListTable->getHeaderSize();
466  }
467  }
468 
469  // Don't fall back to DW_AT_GNU_ranges_base: it should be ignored for
470  // skeleton CU DIE, so that DWARF users not aware of it are not broken.
471  }
472 
473  return DieArray.size();
474 }
475 
476 bool DWARFUnit::parseDWO() {
477  if (IsDWO)
478  return false;
479  if (DWO.get())
480  return false;
481  DWARFDie UnitDie = getUnitDIE();
482  if (!UnitDie)
483  return false;
484  auto DWOFileName = dwarf::toString(UnitDie.find(DW_AT_GNU_dwo_name));
485  if (!DWOFileName)
486  return false;
487  auto CompilationDir = dwarf::toString(UnitDie.find(DW_AT_comp_dir));
488  SmallString<16> AbsolutePath;
489  if (sys::path::is_relative(*DWOFileName) && CompilationDir &&
490  *CompilationDir) {
491  sys::path::append(AbsolutePath, *CompilationDir);
492  }
493  sys::path::append(AbsolutePath, *DWOFileName);
494  auto DWOId = getDWOId();
495  if (!DWOId)
496  return false;
497  auto DWOContext = Context.getDWOContext(AbsolutePath);
498  if (!DWOContext)
499  return false;
500 
501  DWARFCompileUnit *DWOCU = DWOContext->getDWOCompileUnitForHash(*DWOId);
502  if (!DWOCU)
503  return false;
504  DWO = std::shared_ptr<DWARFCompileUnit>(std::move(DWOContext), DWOCU);
505  // Share .debug_addr and .debug_ranges section with compile unit in .dwo
506  DWO->setAddrOffsetSection(AddrOffsetSection, AddrOffsetSectionBase);
507  if (getVersion() >= 5) {
508  DWO->setRangesSection(&Context.getDWARFObj().getRnglistsDWOSection(), 0);
509  DWARFDataExtractor RangesDA(Context.getDWARFObj(), *RangeSection,
510  isLittleEndian, 0);
511  if (auto TableOrError = parseRngListTableHeader(RangesDA, RangeSectionBase))
512  DWO->RngListTable = TableOrError.get();
513  else
514  WithColor::error() << "parsing a range list table: "
515  << toString(TableOrError.takeError())
516  << '\n';
517  if (DWO->RngListTable)
518  DWO->RangeSectionBase = DWO->RngListTable->getHeaderSize();
519  } else {
520  auto DWORangesBase = UnitDie.getRangesBaseAttribute();
521  DWO->setRangesSection(RangeSection, DWORangesBase ? *DWORangesBase : 0);
522  }
523 
524  return true;
525 }
526 
527 void DWARFUnit::clearDIEs(bool KeepCUDie) {
528  if (DieArray.size() > (unsigned)KeepCUDie) {
529  DieArray.resize((unsigned)KeepCUDie);
530  DieArray.shrink_to_fit();
531  }
532 }
533 
536  if (getVersion() <= 4) {
537  DWARFDebugRangeList RangeList;
538  if (Error E = extractRangeList(Offset, RangeList))
539  return std::move(E);
540  return RangeList.getAbsoluteRanges(getBaseAddress());
541  }
542  if (RngListTable) {
543  DWARFDataExtractor RangesData(Context.getDWARFObj(), *RangeSection,
544  isLittleEndian, RngListTable->getAddrSize());
545  auto RangeListOrError = RngListTable->findList(RangesData, Offset);
546  if (RangeListOrError)
547  return RangeListOrError.get().getAbsoluteRanges(getBaseAddress(), *this);
548  return RangeListOrError.takeError();
549  }
550 
552  "missing or invalid range list table");
553 }
554 
557  if (auto Offset = getRnglistOffset(Index))
558  return findRnglistFromOffset(*Offset + RangeSectionBase);
559 
560  if (RngListTable)
562  "invalid range list table index %d", Index);
563  else
565  "missing or invalid range list table");
566 }
567 
569  DWARFDie UnitDie = getUnitDIE();
570  if (!UnitDie)
571  return createStringError(errc::invalid_argument, "No unit DIE");
572 
573  // First, check if unit DIE describes address ranges for the whole unit.
574  auto CUDIERangesOrError = UnitDie.getAddressRanges();
575  if (!CUDIERangesOrError)
577  "decoding address ranges: %s",
578  toString(CUDIERangesOrError.takeError()).c_str());
579  return *CUDIERangesOrError;
580 }
581 
583  if (Die.isSubroutineDIE()) {
584  auto DIERangesOrError = Die.getAddressRanges();
585  if (DIERangesOrError) {
586  for (const auto &R : DIERangesOrError.get()) {
587  // Ignore 0-sized ranges.
588  if (R.LowPC == R.HighPC)
589  continue;
590  auto B = AddrDieMap.upper_bound(R.LowPC);
591  if (B != AddrDieMap.begin() && R.LowPC < (--B)->second.first) {
592  // The range is a sub-range of existing ranges, we need to split the
593  // existing range.
594  if (R.HighPC < B->second.first)
595  AddrDieMap[R.HighPC] = B->second;
596  if (R.LowPC > B->first)
597  AddrDieMap[B->first].first = R.LowPC;
598  }
599  AddrDieMap[R.LowPC] = std::make_pair(R.HighPC, Die);
600  }
601  } else
602  llvm::consumeError(DIERangesOrError.takeError());
603  }
604  // Parent DIEs are added to the AddrDieMap prior to the Children DIEs to
605  // simplify the logic to update AddrDieMap. The child's range will always
606  // be equal or smaller than the parent's range. With this assumption, when
607  // adding one range into the map, it will at most split a range into 3
608  // sub-ranges.
609  for (DWARFDie Child = Die.getFirstChild(); Child; Child = Child.getSibling())
610  updateAddressDieMap(Child);
611 }
612 
614  extractDIEsIfNeeded(false);
615  if (AddrDieMap.empty())
617  auto R = AddrDieMap.upper_bound(Address);
618  if (R == AddrDieMap.begin())
619  return DWARFDie();
620  // upper_bound's previous item contains Address.
621  --R;
622  if (Address >= R->second.first)
623  return DWARFDie();
624  return R->second.second;
625 }
626 
627 void
629  SmallVectorImpl<DWARFDie> &InlinedChain) {
630  assert(InlinedChain.empty());
631  // Try to look for subprogram DIEs in the DWO file.
632  parseDWO();
633  // First, find the subroutine that contains the given address (the leaf
634  // of inlined chain).
635  DWARFDie SubroutineDIE =
636  (DWO ? *DWO : *this).getSubroutineForAddress(Address);
637 
638  if (!SubroutineDIE)
639  return;
640 
641  while (!SubroutineDIE.isSubprogramDIE()) {
642  if (SubroutineDIE.getTag() == DW_TAG_inlined_subroutine)
643  InlinedChain.push_back(SubroutineDIE);
644  SubroutineDIE = SubroutineDIE.getParent();
645  }
646  InlinedChain.push_back(SubroutineDIE);
647 }
648 
651  if (Kind == DW_SECT_INFO)
652  return Context.getCUIndex();
653  assert(Kind == DW_SECT_TYPES);
654  return Context.getTUIndex();
655 }
656 
658  if (!Die)
659  return DWARFDie();
660  const uint32_t Depth = Die->getDepth();
661  // Unit DIEs always have a depth of zero and never have parents.
662  if (Depth == 0)
663  return DWARFDie();
664  // Depth of 1 always means parent is the compile/type unit.
665  if (Depth == 1)
666  return getUnitDIE();
667  // Look for previous DIE with a depth that is one less than the Die's depth.
668  const uint32_t ParentDepth = Depth - 1;
669  for (uint32_t I = getDIEIndex(Die) - 1; I > 0; --I) {
670  if (DieArray[I].getDepth() == ParentDepth)
671  return DWARFDie(this, &DieArray[I]);
672  }
673  return DWARFDie();
674 }
675 
677  if (!Die)
678  return DWARFDie();
679  uint32_t Depth = Die->getDepth();
680  // Unit DIEs always have a depth of zero and never have siblings.
681  if (Depth == 0)
682  return DWARFDie();
683  // NULL DIEs don't have siblings.
684  if (Die->getAbbreviationDeclarationPtr() == nullptr)
685  return DWARFDie();
686 
687  // Find the next DIE whose depth is the same as the Die's depth.
688  for (size_t I = getDIEIndex(Die) + 1, EndIdx = DieArray.size(); I < EndIdx;
689  ++I) {
690  if (DieArray[I].getDepth() == Depth)
691  return DWARFDie(this, &DieArray[I]);
692  }
693  return DWARFDie();
694 }
695 
697  if (!Die)
698  return DWARFDie();
699  uint32_t Depth = Die->getDepth();
700  // Unit DIEs always have a depth of zero and never have siblings.
701  if (Depth == 0)
702  return DWARFDie();
703 
704  // Find the previous DIE whose depth is the same as the Die's depth.
705  for (size_t I = getDIEIndex(Die); I > 0;) {
706  --I;
707  if (DieArray[I].getDepth() == Depth - 1)
708  return DWARFDie();
709  if (DieArray[I].getDepth() == Depth)
710  return DWARFDie(this, &DieArray[I]);
711  }
712  return DWARFDie();
713 }
714 
716  if (!Die->hasChildren())
717  return DWARFDie();
718 
719  // We do not want access out of bounds when parsing corrupted debug data.
720  size_t I = getDIEIndex(Die) + 1;
721  if (I >= DieArray.size())
722  return DWARFDie();
723  return DWARFDie(this, &DieArray[I]);
724 }
725 
727  if (!Die->hasChildren())
728  return DWARFDie();
729 
730  uint32_t Depth = Die->getDepth();
731  for (size_t I = getDIEIndex(Die) + 1, EndIdx = DieArray.size(); I < EndIdx;
732  ++I) {
733  if (DieArray[I].getDepth() == Depth + 1 &&
734  DieArray[I].getTag() == dwarf::DW_TAG_null)
735  return DWARFDie(this, &DieArray[I]);
736  assert(DieArray[I].getDepth() > Depth && "Not processing children?");
737  }
738  return DWARFDie();
739 }
740 
742  if (!Abbrevs)
743  Abbrevs = Abbrev->getAbbreviationDeclarationSet(Header.getAbbrOffset());
744  return Abbrevs;
745 }
746 
748  if (BaseAddr)
749  return BaseAddr;
750 
751  DWARFDie UnitDie = getUnitDIE();
752  Optional<DWARFFormValue> PC = UnitDie.find({DW_AT_low_pc, DW_AT_entry_pc});
753  BaseAddr = toSectionedAddress(PC);
754  return BaseAddr;
755 }
756 
759  DWARFDataExtractor &DA) {
760  uint8_t EntrySize = getDwarfOffsetByteSize();
761  // In order to ensure that we don't read a partial record at the end of
762  // the section we validate for a multiple of the entry size.
763  uint64_t ValidationSize = alignTo(Size, EntrySize);
764  // Guard against overflow.
765  if (ValidationSize >= Size)
766  if (DA.isValidOffsetForDataOfSize((uint32_t)Base, ValidationSize))
767  return *this;
768  return None;
769 }
770 
771 // Look for a DWARF64-formatted contribution to the string offsets table
772 // starting at a given offset and record it in a descriptor.
775  if (!DA.isValidOffsetForDataOfSize(Offset, 16))
776  return None;
777 
778  if (DA.getU32(&Offset) != 0xffffffff)
779  return None;
780 
781  uint64_t Size = DA.getU64(&Offset);
782  uint8_t Version = DA.getU16(&Offset);
783  (void)DA.getU16(&Offset); // padding
784  // The encoded length includes the 2-byte version field and the 2-byte
785  // padding, so we need to subtract them out when we populate the descriptor.
786  return {{Offset, Size - 4, Version, DWARF64}};
787 }
788 
789 // Look for a DWARF32-formatted contribution to the string offsets table
790 // starting at a given offset and record it in a descriptor.
793  if (!DA.isValidOffsetForDataOfSize(Offset, 8))
794  return None;
795  uint32_t ContributionSize = DA.getU32(&Offset);
796  if (ContributionSize >= 0xfffffff0)
797  return None;
798  uint8_t Version = DA.getU16(&Offset);
799  (void)DA.getU16(&Offset); // padding
800  // The encoded length includes the 2-byte version field and the 2-byte
801  // padding, so we need to subtract them out when we populate the descriptor.
802  return {{Offset, ContributionSize - 4, Version, DWARF32}};
803 }
804 
807  auto Offset = toSectionOffset(getUnitDIE().find(DW_AT_str_offsets_base), 0);
809  // Attempt to find a DWARF64 contribution 16 bytes before the base.
810  if (Offset >= 16)
811  Descriptor =
813  // Try to find a DWARF32 contribution 8 bytes before the base.
814  if (!Descriptor && Offset >= 8)
816  return Descriptor ? Descriptor->validateContributionSize(DA) : Descriptor;
817 }
818 
821  uint64_t Offset = 0;
822  auto IndexEntry = Header.getIndexEntry();
823  const auto *C =
824  IndexEntry ? IndexEntry->getOffset(DW_SECT_STR_OFFSETS) : nullptr;
825  if (C)
826  Offset = C->Offset;
827  if (getVersion() >= 5) {
828  // Look for a valid contribution at the given offset.
829  auto Descriptor =
831  if (!Descriptor)
832  Descriptor = parseDWARF32StringOffsetsTableHeader(DA, (uint32_t)Offset);
833  return Descriptor ? Descriptor->validateContributionSize(DA) : Descriptor;
834  }
835  // Prior to DWARF v5, we derive the contribution size from the
836  // index table (in a package file). In a .dwo file it is simply
837  // the length of the string offsets section.
838  if (!IndexEntry)
839  return {{0, StringOffsetSection.Data.size(), 4, DWARF32}};
840  if (C)
841  return {{C->Offset, C->Length, 4, DWARF32}};
842  return None;
843 }
const DWARFAbbreviationDeclarationSet * getAbbreviations() const
Definition: DWARFUnit.cpp:741
const DWARFUnitIndex & getTUIndex()
uint64_t CallInst * C
void getInlinedChainForAddress(uint64_t Address, SmallVectorImpl< DWARFDie > &InlinedChain)
getInlinedChainForAddress - fetches inlined chain for a given address.
Definition: DWARFUnit.cpp:628
virtual ~DWARFUnit()
const_iterator end(StringRef path)
Get end iterator over path.
Definition: Path.cpp:233
virtual const DWARFSection & getAddrSection() const
Definition: DWARFObject.h:69
A helper struct providing information about the byte size of DW_FORM values that vary in size dependi...
Definition: Dwarf.h:499
LLVMContext & Context
const_iterator begin(StringRef path, Style style=Style::native)
Get begin iterator over path.
Definition: Path.cpp:224
virtual const DWARFSection & getLocDWOSection() const
Definition: DWARFObject.h:62
This class represents lattice values for constants.
Definition: AllocatorList.h:23
bool isSubprogramDIE() const
Returns true if DIE represents a subprogram (not inlined).
Definition: DWARFDie.cpp:359
bool isTypeUnit() const
Definition: DWARFUnit.h:286
std::shared_ptr< DWARFContext > getDWOContext(StringRef AbsolutePath)
static raw_ostream & error()
Convenience method for printing "error: " to stderr.
Definition: WithColor.cpp:60
format_object< Ts... > format(const char *Fmt, const Ts &... Vals)
These are helper functions used to produce formatted output.
Definition: Format.h:123
virtual const DWARFSection & getLocSection() const
Definition: DWARFObject.h:40
DWARFDie getSibling(const DWARFDebugInfoEntry *Die)
Definition: DWARFUnit.cpp:676
unsigned second
static raw_ostream & warning()
Convenience method for printing "warning: " to stderr.
Definition: WithColor.cpp:62
static Optional< StrOffsetsContributionDescriptor > parseDWARF64StringOffsetsTableHeader(DWARFDataExtractor &DA, uint32_t Offset)
Definition: DWARFUnit.cpp:774
Optional< StrOffsetsContributionDescriptor > validateContributionSize(DWARFDataExtractor &DA)
Determine whether a contribution to the string offsets table is consistent with the relevant section ...
Definition: DWARFUnit.cpp:758
uint64_t alignTo(uint64_t Value, uint64_t Align, uint64_t Skew=0)
Returns the next integer (mod 2**64) that is greater than or equal to Value and is a multiple of Alig...
Definition: MathExtras.h:684
virtual const DWARFSection & getRnglistsDWOSection() const
Definition: DWARFObject.h:68
block Block Frequency true
const DWARFDebugAbbrev * getDebugAbbrevDWO()
Get a pointer to the parsed dwo abbreviations object.
uint8_t getDwarfStringOffsetsByteSize() const
Definition: DWARFUnit.h:330
uint16_t getU16(uint32_t *offset_ptr) const
Extract a uint16_t value from *offset_ptr.
void addUnitsForSection(DWARFContext &C, const DWARFSection &Section, DWARFSectionKind SectionKind)
Read units from a .debug_info or .debug_types section.
Definition: DWARFUnit.cpp:36
DWARFDie getSubroutineForAddress(uint64_t Address)
Returns subprogram DIE with address range encompassing the provided address.
Definition: DWARFUnit.cpp:613
static Optional< StrOffsetsContributionDescriptor > parseDWARF32StringOffsetsTableHeader(DWARFDataExtractor &DA, uint32_t Offset)
Definition: DWARFUnit.cpp:792
virtual bool isLittleEndian() const =0
uint32_t getNextUnitOffset() const
Definition: DWARFUnit.h:287
Optional< StrOffsetsContributionDescriptor > determineStringOffsetsTableContributionDWO(DWARFDataExtractor &DA)
Find the unit&#39;s contribution to the string offsets table and determine its length and form...
Definition: DWARFUnit.cpp:820
void append(SmallVectorImpl< char > &path, const Twine &a, const Twine &b="", const Twine &c="", const Twine &d="")
Append to path.
Definition: Path.cpp:455
DWARFUnit(DWARFContext &Context, const DWARFSection &Section, const DWARFUnitHeader &Header, const DWARFDebugAbbrev *DA, const DWARFSection *RS, const DWARFSection *LocSection, StringRef SS, const DWARFSection &SOS, const DWARFSection *AOS, const DWARFSection &LS, bool LE, bool IsDWO, const DWARFUnitVector &UnitVector)
Definition: DWARFUnit.cpp:171
std::string toString(Error E)
Write all error messages (if any) in E to a string.
Definition: Error.h:966
uint32_t getU32(uint32_t *offset_ptr) const
Extract a uint32_t value from *offset_ptr.
static ManagedStatic< DebugCounter > DC
Optional< StrOffsetsContributionDescriptor > determineStringOffsetsTableContribution(DWARFDataExtractor &DA)
Find the unit&#39;s contribution to the string offsets table and determine its length and form...
Definition: DWARFUnit.cpp:806
const char * getCompilationDir()
Definition: DWARFUnit.cpp:341
Optional< uint64_t > getRangesBaseAttribute() const
Extract the range base attribute from this DIE as absolute section offset.
Definition: DWARFDie.cpp:441
uint64_t getAbbrOffset() const
Definition: DWARFUnit.h:86
This class consists of common code factored out of the SmallVector class to reduce code duplication b...
Definition: APFloat.h:41
DWARFUnit * addUnit(std::unique_ptr< DWARFUnit > Unit)
Add an existing DWARFUnit to this UnitVector.
Definition: DWARFUnit.cpp:120
Error extractRangeList(uint32_t RangeListOffset, DWARFDebugRangeList &RangeList) const
Extract the range list referenced by this compile unit from the .debug_ranges section.
Definition: DWARFUnit.cpp:322
Tagged union holding either a T or a Error.
Definition: CachePruning.h:22
LLVM_NODISCARD StringRef substr(size_t Start, size_t N=npos) const
Return a reference to the substring from [Start, Start + N).
Definition: StringRef.h:578
bool isTypeUnit() const
Definition: DWARFUnit.h:96
virtual const DWARFSection & getStringOffsetDWOSection() const
Definition: DWARFObject.h:64
uint8_t getAddressByteSize() const
Definition: DWARFUnit.h:279
Optional< object::SectionedAddress > toSectionedAddress(const Optional< DWARFFormValue > &V)
DWARFAddressRangesVector getAbsoluteRanges(llvm::Optional< object::SectionedAddress > BaseAddr) const
getAbsoluteRanges - Returns absolute address ranges defined by this range list.
LLVM_NODISCARD size_t size() const
size - Get the string size.
Definition: StringRef.h:130
SmallString - A SmallString is just a SmallVector with methods and accessors that make it work better...
Definition: SmallString.h:25
llvm::Optional< object::SectionedAddress > getBaseAddress()
Definition: DWARFUnit.cpp:747
const DWARFDebugAbbrev * getDebugAbbrev()
Get a pointer to the parsed DebugAbbrev object.
DWARFDie getLastChild(const DWARFDebugInfoEntry *Die)
Definition: DWARFUnit.cpp:726
uint16_t getVersion() const
Definition: DWARFUnit.h:278
DWARFDie getSibling() const
Get the sibling of this DIE object.
Definition: DWARFDie.cpp:634
Expected< DWARFAddressRangesVector > findRnglistFromIndex(uint32_t Index)
Return a vector of address ranges retrieved from an encoded range list whose offset is found via a ta...
Definition: DWARFUnit.cpp:556
DWARFDie getFirstChild(const DWARFDebugInfoEntry *Die)
Definition: DWARFUnit.cpp:715
unit_iterator_range info_section_units()
Get units from .debug_info in this context.
Definition: DWARFContext.h:137
Optional< uint64_t > toSectionOffset(const Optional< DWARFFormValue > &V)
Take an optional DWARFFormValue and try to extract an section offset.
bool isValidOffsetForDataOfSize(uint32_t offset, uint32_t length) const
Test the availability of length bytes of data from offset.
Utility class that carries the DWARF compile/type unit and the debug info entry in an object...
Definition: DWARFDie.h:42
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
virtual const DWARFSection & getStringOffsetSection() const
Definition: DWARFObject.h:55
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
DWARFSectionKind
A structured debug information entry.
Definition: DIE.h:700
bool isSubroutineDIE() const
Returns true if DIE represents a subprogram or an inlined subroutine.
Definition: DWARFDie.cpp:361
Optional< uint64_t > getDWOId()
Definition: DWARFUnit.h:396
Expected< DWARFAddressRangesVector > collectAddressRanges()
Definition: DWARFUnit.cpp:568
bool extract(DWARFContext &Context, const DWARFDataExtractor &debug_info, uint32_t *offset_ptr, DWARFSectionKind Kind=DW_SECT_INFO, const DWARFUnitIndex *Index=nullptr, const DWARFUnitIndex::Entry *Entry=nullptr)
Parse a unit header from debug_info starting at offset_ptr.
Definition: DWARFUnit.cpp:234
bool extractFast(const DWARFUnit &U, uint32_t *OffsetPtr)
Extracts a debug info entry, which is a child of a given unit, starting at a given offset...
const DWARFAbbreviationDeclarationSet * getAbbreviationDeclarationSet(uint64_t CUAbbrOffset) const
DWARFDie getParent(const DWARFDebugInfoEntry *Die)
Definition: DWARFUnit.cpp:657
virtual const DWARFSection & getLineDWOSection() const
Definition: DWARFObject.h:61
uint8_t getU8(uint32_t *offset_ptr) const
Extract a uint8_t value from *offset_ptr.
SectionKind - This is a simple POD value that classifies the properties of a section.
Definition: SectionKind.h:22
virtual StringRef getStringSection() const
Definition: DWARFObject.h:47
void setRangesSection(const DWARFSection *RS, uint32_t Base)
Definition: DWARFUnit.h:302
virtual StringRef getStringDWOSection() const
Definition: DWARFObject.h:63
uint32_t getHeaderSize() const
Size in bytes of the parsed unit header.
Definition: DWARFUnit.h:244
uint64_t getU64(uint32_t *offset_ptr) const
Extract a uint64_t value from *offset_ptr.
void consumeError(Error Err)
Consume a Error without doing anything.
Definition: Error.h:981
const DWARFUnitIndex & getDWARFUnitIndex(DWARFContext &Context, DWARFSectionKind Kind)
Definition: DWARFUnit.cpp:649
auto find(R &&Range, const T &Val) -> decltype(adl_begin(Range))
Provide wrappers to std::find which take ranges instead of having to pass begin/end explicitly...
Definition: STLExtras.h:1206
DWARFUnit * getUnitForOffset(uint32_t Offset) const
Definition: DWARFUnit.cpp:129
Base class describing the header of any kind of "unit." Some information is specific to certain unit ...
Definition: DWARFUnit.h:46
uint64_t getRelocatedValue(uint32_t Size, uint32_t *Off, uint64_t *SectionIndex=nullptr) const
Extracts a value and applies a relocation to the result if one exists for the given offset...
UnitType
Constants for unit types in DWARF v5.
Definition: Dwarf.h:330
DWARFUnit * getUnitForIndexEntry(const DWARFUnitIndex::Entry &E)
Definition: DWARFUnit.cpp:142
A DataExtractor (typically for an in-memory copy of an object-file section) plus a relocation map for...
uint64_t getStringOffsetsBase() const
Definition: DWARFUnit.h:335
DWARFDie getUnitDIE(bool ExtractUnitDIEOnly=true)
Definition: DWARFUnit.h:381
const DWARFAbbreviationDeclaration * getAbbreviationDeclarationPtr() const
void setDWOId(uint64_t Id)
Definition: DWARFUnit.h:88
SmallVectorImpl< T >::const_pointer c_str(SmallVectorImpl< T > &str)
const DWARFUnitIndex::Entry * getIndexEntry() const
Definition: DWARFUnit.h:92
static Expected< DWARFDebugRnglistTable > parseRngListTableHeader(DWARFDataExtractor &DA, uint32_t Offset)
Definition: DWARFUnit.cpp:305
void addUnitsForDWOSection(DWARFContext &C, const DWARFSection &DWOSection, DWARFSectionKind SectionKind, bool Lazy=false)
Read units from a .debug_info.dwo or .debug_types.dwo section.
Definition: DWARFUnit.cpp:47
static unsigned getDepth(const SmallVectorImpl< const MachineBasicBlock *> &Stack, const MachineBasicBlock *MBB)
Error extractHeaderAndOffsets(DWARFDataExtractor Data, uint32_t *OffsetPtr)
Extract the table header and the array of offsets.
DWARFContext This data structure is the top level entity that deals with dwarf debug information pars...
Definition: DWARFContext.h:58
static GCRegistry::Add< StatepointGC > D("statepoint-example", "an example strategy for statepoint")
Describe a collection of units.
Definition: DWARFUnit.h:109
Optional< const char * > toString(const Optional< DWARFFormValue > &V)
Take an optional DWARFFormValue and try to extract a string value from it.
virtual const DWARFSection & getRnglistsSection() const
Definition: DWARFObject.h:49
uint32_t getLength() const
Definition: DWARFUnit.h:284
DWARFDataExtractor getDebugInfoExtractor() const
Definition: DWARFUnit.cpp:195
virtual const DWARFSection & getLineSection() const
Definition: DWARFObject.h:45
static bool isSupportedVersion(unsigned version)
Definition: DWARFContext.h:335
virtual const DWARFSection & getRangeDWOSection() const
Definition: DWARFObject.h:67
dwarf::Tag getTag() const
Definition: DWARFDie.h:71
LLVM_NODISCARD bool empty() const
Definition: SmallVector.h:55
Expected< DWARFAddressRangesVector > findRnglistFromOffset(uint32_t Offset)
Return a vector of address ranges resulting from a (possibly encoded) range list starting at a given ...
Definition: DWARFUnit.cpp:535
#define I(x, y, z)
Definition: MD5.cpp:58
bool is_relative(const Twine &path, Style style=Style::native)
Is path relative?
Definition: Path.cpp:674
uint32_t getOffset() const
Definition: DWARFUnit.h:274
Expected< DWARFAddressRangesVector > getAddressRanges() const
Get the address ranges for this DIE.
Definition: DWARFDie.cpp:474
DWARFDie getPreviousSibling(const DWARFDebugInfoEntry *Die)
Definition: DWARFUnit.cpp:696
uint32_t Size
Definition: Profile.cpp:46
void updateAddressDieMap(DWARFDie Die)
Recursively update address to Die map.
Definition: DWARFUnit.cpp:582
bool isLittleEndian() const
Definition: DWARFContext.h:334
const DWARFObject & getDWARFObj() const
Definition: DWARFContext.h:116
bool isValidOffset(uint32_t offset) const
Test the validity of offset.
const DWARFUnitIndex & getCUIndex()
virtual const DWARFSection & getRangeSection() const
Definition: DWARFObject.h:48
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
DwarfFormat Format
Definition: Dwarf.h:502
Optional< DWARFFormValue > find(dwarf::Attribute Attr) const
Extract the specified attribute from this DIE.
Definition: DWARFDie.cpp:366
DWARFDebugInfoEntry - A DIE with only the minimum required data.
DWARFDie getFirstChild() const
Get the first child of this DIE object.
Definition: DWARFDie.cpp:646
Lightweight error class with error context and mandatory checking.
Definition: Error.h:157
const Entry * getFromOffset(uint32_t Offset) const
const SectionContribution * getOffset(DWARFSectionKind Sec) const
Optional< object::SectionedAddress > getAddrOffsetSectionItem(uint32_t Index) const
Definition: DWARFUnit.cpp:201
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:48
Optional< uint32_t > getRnglistOffset(uint32_t Index)
Return a rangelist&#39;s offset based on an index.
Definition: DWARFUnit.h:414
const uint64_t Version
Definition: InstrProf.h:984
uint8_t getDwarfOffsetByteSize() const
Definition: DWARFUnit.h:281
void setMaxVersionIfGreater(unsigned Version)
Definition: DWARFContext.h:245
StringRef LocSectionData
Definition: DWARFUnit.h:201
Optional< uint64_t > toUnsigned(const Optional< DWARFFormValue > &V)
Take an optional DWARFFormValue and try to extract an unsigned constant.
Error createStringError(std::error_code EC, char const *Fmt, const Ts &... Vals)
Create formatted StringError object.
Definition: Error.h:1163
Optional< uint64_t > getStringOffsetSectionItem(uint32_t Index) const
Definition: DWARFUnit.cpp:222
DWARFDie getParent() const
Get the parent of this DIE object.
Definition: DWARFDie.cpp:628
Error extract(const DWARFDataExtractor &data, uint32_t *offset_ptr)
auto upper_bound(R &&Range, T &&Value) -> decltype(adl_begin(Range))
Provide wrappers to std::upper_bound which take ranges instead of having to pass begin/end explicitly...
Definition: STLExtras.h:1296