1 //===- DWARFUnit.cpp ------------------------------------------------------===//
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
7 //===----------------------------------------------------------------------===//
9 #include "llvm/DebugInfo/DWARF/DWARFUnit.h"
10 #include "llvm/ADT/SmallString.h"
11 #include "llvm/ADT/StringRef.h"
12 #include "llvm/DebugInfo/DWARF/DWARFAbbreviationDeclaration.h"
13 #include "llvm/DebugInfo/DWARF/DWARFCompileUnit.h"
14 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
15 #include "llvm/DebugInfo/DWARF/DWARFDebugAbbrev.h"
16 #include "llvm/DebugInfo/DWARF/DWARFDebugInfoEntry.h"
17 #include "llvm/DebugInfo/DWARF/DWARFDebugRnglists.h"
18 #include "llvm/DebugInfo/DWARF/DWARFDie.h"
19 #include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
20 #include "llvm/DebugInfo/DWARF/DWARFTypeUnit.h"
21 #include "llvm/Support/DataExtractor.h"
22 #include "llvm/Support/Errc.h"
23 #include "llvm/Support/Path.h"
24 #include "llvm/Support/WithColor.h"
34 using namespace dwarf;
36 void DWARFUnitVector::addUnitsForSection(DWARFContext &C,
37 const DWARFSection &Section,
38 DWARFSectionKind SectionKind) {
39 const DWARFObject &D = C.getDWARFObj();
40 addUnitsImpl(C, D, Section, C.getDebugAbbrev(), &D.getRangesSection(),
41 &D.getLocSection(), D.getStrSection(),
42 D.getStrOffsetsSection(), &D.getAddrSection(),
43 D.getLineSection(), D.isLittleEndian(), false, false,
47 void DWARFUnitVector::addUnitsForDWOSection(DWARFContext &C,
48 const DWARFSection &DWOSection,
49 DWARFSectionKind SectionKind,
51 const DWARFObject &D = C.getDWARFObj();
52 addUnitsImpl(C, D, DWOSection, C.getDebugAbbrevDWO(), &D.getRangesDWOSection(),
53 &D.getLocDWOSection(), D.getStrDWOSection(),
54 D.getStrOffsetsDWOSection(), &D.getAddrSection(),
55 D.getLineDWOSection(), C.isLittleEndian(), true, Lazy,
59 void DWARFUnitVector::addUnitsImpl(
60 DWARFContext &Context, const DWARFObject &Obj, const DWARFSection &Section,
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.
68 Parser = [=, &Context, &Obj, &Section, &SOS,
69 &LS](uint64_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))
77 const DWARFUnitIndex *Index = nullptr;
79 Index = &getDWARFUnitIndex(Context, SectionKind);
80 DWARFUnitHeader Header;
81 if (!Header.extract(Context, Data, &Offset, SectionKind, Index,
84 std::unique_ptr<DWARFUnit> U;
85 if (Header.isTypeUnit())
86 U = std::make_unique<DWARFTypeUnit>(Context, InfoSection, Header, DA,
87 RS, LocSection, SS, SOS, AOS, LS,
90 U = std::make_unique<DWARFCompileUnit>(Context, InfoSection, Header,
91 DA, RS, LocSection, SS, SOS,
92 AOS, LS, LE, IsDWO, *this);
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();
105 while (Data.isValidOffset(Offset)) {
106 if (I != this->end() &&
107 (&(*I)->getInfoSection() != &Section || (*I)->getOffset() == Offset)) {
111 auto U = Parser(Offset, SectionKind, &Section, nullptr);
112 // If parsing failed, we're done with this section.
115 Offset = U->getNextUnitOffset();
116 I = std::next(this->insert(I, std::move(U)));
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();
126 return this->insert(I, std::move(Unit))->get();
129 DWARFUnit *DWARFUnitVector::getUnitForOffset(uint64_t Offset) const {
130 auto end = begin() + getNumInfoUnits();
132 std::upper_bound(begin(), end, Offset,
133 [](uint64_t LHS, const std::unique_ptr<DWARFUnit> &RHS) {
134 return LHS < RHS->getNextUnitOffset();
136 if (CU != end && (*CU)->getOffset() <= Offset)
142 DWARFUnitVector::getUnitForIndexEntry(const DWARFUnitIndex::Entry &E) {
143 const auto *CUOff = E.getOffset(DW_SECT_INFO);
147 auto Offset = CUOff->Offset;
148 auto end = begin() + getNumInfoUnits();
151 std::upper_bound(begin(), end, CUOff->Offset,
152 [](uint64_t LHS, const std::unique_ptr<DWARFUnit> &RHS) {
153 return LHS < RHS->getNextUnitOffset();
155 if (CU != end && (*CU)->getOffset() <= Offset)
161 auto U = Parser(Offset, DW_SECT_INFO, nullptr, &E);
165 auto *NewCU = U.get();
166 this->insert(CU, std::move(U));
171 DWARFUnit::DWARFUnit(DWARFContext &DC, const DWARFSection &Section,
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), LineSection(LS), StringSection(SS),
179 StringOffsetSection(SOS), AddrOffsetSection(AOS), isLittleEndian(LE),
180 IsDWO(IsDWO), UnitVector(UnitVector) {
183 // If we are reading a package file, we need to adjust the location list
184 // data based on the index entries.
185 StringRef Data = LocSection->Data;
186 if (auto *IndexEntry = Header.getIndexEntry())
187 if (const auto *C = IndexEntry->getOffset(DW_SECT_LOC))
188 Data = Data.substr(C->Offset, C->Length);
190 DWARFDataExtractor DWARFData =
191 Header.getVersion() >= 5
192 ? DWARFDataExtractor(Context.getDWARFObj(),
193 Context.getDWARFObj().getLoclistsDWOSection(),
194 isLittleEndian, getAddressByteSize())
195 : DWARFDataExtractor(Data, isLittleEndian, getAddressByteSize());
197 std::make_unique<DWARFDebugLoclists>(DWARFData, Header.getVersion());
199 } else if (Header.getVersion() >= 5) {
200 LocTable = std::make_unique<DWARFDebugLoclists>(
201 DWARFDataExtractor(Context.getDWARFObj(),
202 Context.getDWARFObj().getLoclistsSection(),
203 isLittleEndian, getAddressByteSize()),
204 Header.getVersion());
206 LocTable = std::make_unique<DWARFDebugLoc>(
207 DWARFDataExtractor(Context.getDWARFObj(), *LocSection, isLittleEndian,
208 getAddressByteSize()));
212 DWARFUnit::~DWARFUnit() = default;
214 DWARFDataExtractor DWARFUnit::getDebugInfoExtractor() const {
215 return DWARFDataExtractor(Context.getDWARFObj(), InfoSection, isLittleEndian,
216 getAddressByteSize());
219 Optional<object::SectionedAddress>
220 DWARFUnit::getAddrOffsetSectionItem(uint32_t Index) const {
222 auto R = Context.info_section_units();
224 // Surprising if a DWO file has more than one skeleton unit in it - this
225 // probably shouldn't be valid, but if a use case is found, here's where to
226 // support it (probably have to linearly search for the matching skeleton CU
228 if (I != R.end() && std::next(I) == R.end())
229 return (*I)->getAddrOffsetSectionItem(Index);
231 if (!AddrOffsetSectionBase)
233 uint64_t Offset = *AddrOffsetSectionBase + Index * getAddressByteSize();
234 if (AddrOffsetSection->Data.size() < Offset + getAddressByteSize())
236 DWARFDataExtractor DA(Context.getDWARFObj(), *AddrOffsetSection,
237 isLittleEndian, getAddressByteSize());
239 uint64_t Address = DA.getRelocatedAddress(&Offset, &Section);
240 return {{Address, Section}};
243 Optional<uint64_t> DWARFUnit::getStringOffsetSectionItem(uint32_t Index) const {
244 if (!StringOffsetsTableContribution)
246 unsigned ItemSize = getDwarfStringOffsetsByteSize();
247 uint64_t Offset = getStringOffsetsBase() + Index * ItemSize;
248 if (StringOffsetSection.Data.size() < Offset + ItemSize)
250 DWARFDataExtractor DA(Context.getDWARFObj(), StringOffsetSection,
252 return DA.getRelocatedValue(ItemSize, &Offset);
255 bool DWARFUnitHeader::extract(DWARFContext &Context,
256 const DWARFDataExtractor &debug_info,
257 uint64_t *offset_ptr,
258 DWARFSectionKind SectionKind,
259 const DWARFUnitIndex *Index,
260 const DWARFUnitIndex::Entry *Entry) {
261 Offset = *offset_ptr;
262 Error Err = Error::success();
264 if (!IndexEntry && Index)
265 IndexEntry = Index->getFromOffset(*offset_ptr);
266 Length = debug_info.getRelocatedValue(4, offset_ptr, nullptr, &Err);
267 FormParams.Format = DWARF32;
268 if (Length == dwarf::DW_LENGTH_DWARF64) {
269 Length = debug_info.getU64(offset_ptr, &Err);
270 FormParams.Format = DWARF64;
272 FormParams.Version = debug_info.getU16(offset_ptr, &Err);
273 if (FormParams.Version >= 5) {
274 UnitType = debug_info.getU8(offset_ptr, &Err);
275 FormParams.AddrSize = debug_info.getU8(offset_ptr, &Err);
276 AbbrOffset = debug_info.getRelocatedValue(
277 FormParams.getDwarfOffsetByteSize(), offset_ptr, nullptr, &Err);
279 AbbrOffset = debug_info.getRelocatedValue(
280 FormParams.getDwarfOffsetByteSize(), offset_ptr, nullptr, &Err);
281 FormParams.AddrSize = debug_info.getU8(offset_ptr, &Err);
282 // Fake a unit type based on the section type. This isn't perfect,
283 // but distinguishing compile and type units is generally enough.
284 if (SectionKind == DW_SECT_TYPES)
285 UnitType = DW_UT_type;
287 UnitType = DW_UT_compile;
292 auto *UnitContrib = IndexEntry->getOffset();
293 if (!UnitContrib || UnitContrib->Length != (Length + 4))
295 auto *AbbrEntry = IndexEntry->getOffset(DW_SECT_ABBREV);
298 AbbrOffset = AbbrEntry->Offset;
301 TypeHash = debug_info.getU64(offset_ptr, &Err);
302 TypeOffset = debug_info.getUnsigned(
303 offset_ptr, FormParams.getDwarfOffsetByteSize(), &Err);
304 } else if (UnitType == DW_UT_split_compile || UnitType == DW_UT_skeleton)
305 DWOId = debug_info.getU64(offset_ptr, &Err);
307 if (errorToBool(std::move(Err)))
310 // Header fields all parsed, capture the size of this unit header.
311 assert(*offset_ptr - Offset <= 255 && "unexpected header size");
312 Size = uint8_t(*offset_ptr - Offset);
314 // Type offset is unit-relative; should be after the header and before
315 // the end of the current unit.
319 : TypeOffset >= Size &&
320 TypeOffset < getLength() + getUnitLengthFieldByteSize();
321 bool LengthOK = debug_info.isValidOffset(getNextUnitOffset() - 1);
322 bool VersionOK = DWARFContext::isSupportedVersion(getVersion());
323 bool AddrSizeOK = getAddressByteSize() == 4 || getAddressByteSize() == 8;
325 if (!LengthOK || !VersionOK || !AddrSizeOK || !TypeOffsetOK)
328 // Keep track of the highest DWARF version we encounter across all units.
329 Context.setMaxVersionIfGreater(getVersion());
333 // Parse the rangelist table header, including the optional array of offsets
334 // following it (DWARF v5 and later).
335 template<typename ListTableType>
336 static Expected<ListTableType>
337 parseListTableHeader(DWARFDataExtractor &DA, uint64_t Offset,
338 DwarfFormat Format) {
339 // We are expected to be called with Offset 0 or pointing just past the table
340 // header. Correct Offset in the latter case so that it points to the start
343 uint64_t HeaderSize = DWARFListTableHeader::getHeaderSize(Format);
344 if (Offset < HeaderSize)
345 return createStringError(errc::invalid_argument, "did not detect a valid"
346 " list table with base = 0x%" PRIx64 "\n",
348 Offset -= HeaderSize;
351 if (Error E = Table.extractHeaderAndOffsets(DA, &Offset))
356 Error DWARFUnit::extractRangeList(uint64_t RangeListOffset,
357 DWARFDebugRangeList &RangeList) const {
358 // Require that compile unit is extracted.
359 assert(!DieArray.empty());
360 DWARFDataExtractor RangesData(Context.getDWARFObj(), *RangeSection,
361 isLittleEndian, getAddressByteSize());
362 uint64_t ActualRangeListOffset = RangeSectionBase + RangeListOffset;
363 return RangeList.extract(RangesData, &ActualRangeListOffset);
366 void DWARFUnit::clear() {
369 RangeSectionBase = 0;
371 AddrOffsetSectionBase = None;
376 const char *DWARFUnit::getCompilationDir() {
377 return dwarf::toString(getUnitDIE().find(DW_AT_comp_dir), nullptr);
380 void DWARFUnit::extractDIEsToVector(
381 bool AppendCUDie, bool AppendNonCUDies,
382 std::vector<DWARFDebugInfoEntry> &Dies) const {
383 if (!AppendCUDie && !AppendNonCUDies)
386 // Set the offset to that of the first DIE and calculate the start of the
387 // next compilation unit header.
388 uint64_t DIEOffset = getOffset() + getHeaderSize();
389 uint64_t NextCUOffset = getNextUnitOffset();
390 DWARFDebugInfoEntry DIE;
391 DWARFDataExtractor DebugInfoData = getDebugInfoExtractor();
395 while (DIE.extractFast(*this, &DIEOffset, DebugInfoData, NextCUOffset,
400 if (!AppendNonCUDies)
402 // The average bytes per DIE entry has been seen to be
403 // around 14-20 so let's pre-reserve the needed memory for
404 // our DIE entries accordingly.
405 Dies.reserve(Dies.size() + getDebugInfoSize() / 14);
411 if (const DWARFAbbreviationDeclaration *AbbrDecl =
412 DIE.getAbbreviationDeclarationPtr()) {
414 if (AbbrDecl->hasChildren())
421 break; // We are done with this compile unit!
425 // Give a little bit of info if we encounter corrupt DWARF (our offset
426 // should always terminate at or before the start of the next compilation
428 if (DIEOffset > NextCUOffset)
429 WithColor::warning() << format("DWARF compile unit extends beyond its "
430 "bounds cu 0x%8.8" PRIx64 " "
431 "at 0x%8.8" PRIx64 "\n",
432 getOffset(), DIEOffset);
435 void DWARFUnit::extractDIEsIfNeeded(bool CUDieOnly) {
436 if (Error e = tryExtractDIEsIfNeeded(CUDieOnly))
437 WithColor::error() << toString(std::move(e));
440 Error DWARFUnit::tryExtractDIEsIfNeeded(bool CUDieOnly) {
441 if ((CUDieOnly && !DieArray.empty()) ||
443 return Error::success(); // Already parsed.
445 bool HasCUDie = !DieArray.empty();
446 extractDIEsToVector(!HasCUDie, !CUDieOnly, DieArray);
448 if (DieArray.empty())
449 return Error::success();
451 // If CU DIE was just parsed, copy several attribute values from it.
453 return Error::success();
455 DWARFDie UnitDie(this, &DieArray[0]);
456 if (Optional<uint64_t> DWOId = toUnsigned(UnitDie.find(DW_AT_GNU_dwo_id)))
457 Header.setDWOId(*DWOId);
459 assert(AddrOffsetSectionBase == None);
460 assert(RangeSectionBase == 0);
461 assert(LocSectionBase == 0);
462 AddrOffsetSectionBase = toSectionOffset(UnitDie.find(DW_AT_addr_base));
463 if (!AddrOffsetSectionBase)
464 AddrOffsetSectionBase =
465 toSectionOffset(UnitDie.find(DW_AT_GNU_addr_base));
466 RangeSectionBase = toSectionOffset(UnitDie.find(DW_AT_rnglists_base), 0);
467 LocSectionBase = toSectionOffset(UnitDie.find(DW_AT_loclists_base), 0);
470 // In general, in DWARF v5 and beyond we derive the start of the unit's
471 // contribution to the string offsets table from the unit DIE's
472 // DW_AT_str_offsets_base attribute. Split DWARF units do not use this
473 // attribute, so we assume that there is a contribution to the string
474 // offsets table starting at offset 0 of the debug_str_offsets.dwo section.
475 // In both cases we need to determine the format of the contribution,
476 // which may differ from the unit's format.
477 DWARFDataExtractor DA(Context.getDWARFObj(), StringOffsetSection,
479 if (IsDWO || getVersion() >= 5) {
480 auto StringOffsetOrError =
481 IsDWO ? determineStringOffsetsTableContributionDWO(DA)
482 : determineStringOffsetsTableContribution(DA);
483 if (!StringOffsetOrError)
484 return createStringError(errc::invalid_argument,
485 "invalid reference to or invalid content in "
486 ".debug_str_offsets[.dwo]: " +
487 toString(StringOffsetOrError.takeError()));
489 StringOffsetsTableContribution = *StringOffsetOrError;
492 // DWARF v5 uses the .debug_rnglists and .debug_rnglists.dwo sections to
493 // describe address ranges.
494 if (getVersion() >= 5) {
496 setRangesSection(&Context.getDWARFObj().getRnglistsDWOSection(), 0);
498 setRangesSection(&Context.getDWARFObj().getRnglistsSection(),
499 toSectionOffset(UnitDie.find(DW_AT_rnglists_base), 0));
500 if (RangeSection->Data.size()) {
501 // Parse the range list table header. Individual range lists are
503 DWARFDataExtractor RangesDA(Context.getDWARFObj(), *RangeSection,
505 auto TableOrError = parseListTableHeader<DWARFDebugRnglistTable>(
506 RangesDA, RangeSectionBase, Header.getFormat());
508 return createStringError(errc::invalid_argument,
509 "parsing a range list table: " +
510 toString(TableOrError.takeError()));
512 RngListTable = TableOrError.get();
514 // In a split dwarf unit, there is no DW_AT_rnglists_base attribute.
515 // Adjust RangeSectionBase to point past the table header.
516 if (IsDWO && RngListTable)
517 RangeSectionBase = RngListTable->getHeaderSize();
520 // In a split dwarf unit, there is no DW_AT_loclists_base attribute.
521 // Setting LocSectionBase to point past the table header.
523 setLocSection(&Context.getDWARFObj().getLoclistsDWOSection(),
524 DWARFListTableHeader::getHeaderSize(Header.getFormat()));
526 setLocSection(&Context.getDWARFObj().getLoclistsSection(),
527 toSectionOffset(UnitDie.find(DW_AT_loclists_base), 0));
529 if (LocSection->Data.size()) {
531 LoclistTableHeader.emplace(".debug_loclists.dwo", "locations");
533 LoclistTableHeader.emplace(".debug_loclists", "locations");
535 uint64_t HeaderSize = DWARFListTableHeader::getHeaderSize(Header.getFormat());
536 uint64_t Offset = getLocSectionBase();
537 DWARFDataExtractor Data(Context.getDWARFObj(), *LocSection,
538 isLittleEndian, getAddressByteSize());
539 if (Offset < HeaderSize)
540 return createStringError(errc::invalid_argument,
541 "did not detect a valid"
542 " list table with base = 0x%" PRIx64 "\n",
544 Offset -= HeaderSize;
545 if (Error E = LoclistTableHeader->extract(Data, &Offset))
546 return createStringError(errc::invalid_argument,
547 "parsing a loclist table: " +
548 toString(std::move(E)));
552 // Don't fall back to DW_AT_GNU_ranges_base: it should be ignored for
553 // skeleton CU DIE, so that DWARF users not aware of it are not broken.
554 return Error::success();
557 bool DWARFUnit::parseDWO() {
562 DWARFDie UnitDie = getUnitDIE();
565 auto DWOFileName = getVersion() >= 5
566 ? dwarf::toString(UnitDie.find(DW_AT_dwo_name))
567 : dwarf::toString(UnitDie.find(DW_AT_GNU_dwo_name));
570 auto CompilationDir = dwarf::toString(UnitDie.find(DW_AT_comp_dir));
571 SmallString<16> AbsolutePath;
572 if (sys::path::is_relative(*DWOFileName) && CompilationDir &&
574 sys::path::append(AbsolutePath, *CompilationDir);
576 sys::path::append(AbsolutePath, *DWOFileName);
577 auto DWOId = getDWOId();
580 auto DWOContext = Context.getDWOContext(AbsolutePath);
584 DWARFCompileUnit *DWOCU = DWOContext->getDWOCompileUnitForHash(*DWOId);
587 DWO = std::shared_ptr<DWARFCompileUnit>(std::move(DWOContext), DWOCU);
588 // Share .debug_addr and .debug_ranges section with compile unit in .dwo
589 if (AddrOffsetSectionBase)
590 DWO->setAddrOffsetSection(AddrOffsetSection, *AddrOffsetSectionBase);
591 if (getVersion() >= 5) {
592 DWO->setRangesSection(&Context.getDWARFObj().getRnglistsDWOSection(), 0);
593 DWARFDataExtractor RangesDA(Context.getDWARFObj(), *RangeSection,
595 if (auto TableOrError = parseListTableHeader<DWARFDebugRnglistTable>(
596 RangesDA, RangeSectionBase, Header.getFormat()))
597 DWO->RngListTable = TableOrError.get();
599 WithColor::error() << "parsing a range list table: "
600 << toString(TableOrError.takeError())
602 if (DWO->RngListTable)
603 DWO->RangeSectionBase = DWO->RngListTable->getHeaderSize();
605 auto DWORangesBase = UnitDie.getRangesBaseAttribute();
606 DWO->setRangesSection(RangeSection, DWORangesBase ? *DWORangesBase : 0);
612 void DWARFUnit::clearDIEs(bool KeepCUDie) {
613 if (DieArray.size() > (unsigned)KeepCUDie) {
614 DieArray.resize((unsigned)KeepCUDie);
615 DieArray.shrink_to_fit();
619 Expected<DWARFAddressRangesVector>
620 DWARFUnit::findRnglistFromOffset(uint64_t Offset) {
621 if (getVersion() <= 4) {
622 DWARFDebugRangeList RangeList;
623 if (Error E = extractRangeList(Offset, RangeList))
625 return RangeList.getAbsoluteRanges(getBaseAddress());
628 DWARFDataExtractor RangesData(Context.getDWARFObj(), *RangeSection,
629 isLittleEndian, RngListTable->getAddrSize());
630 auto RangeListOrError = RngListTable->findList(RangesData, Offset);
631 if (RangeListOrError)
632 return RangeListOrError.get().getAbsoluteRanges(getBaseAddress(), *this);
633 return RangeListOrError.takeError();
636 return createStringError(errc::invalid_argument,
637 "missing or invalid range list table");
640 Expected<DWARFAddressRangesVector>
641 DWARFUnit::findRnglistFromIndex(uint32_t Index) {
642 if (auto Offset = getRnglistOffset(Index))
643 return findRnglistFromOffset(*Offset);
646 return createStringError(errc::invalid_argument,
647 "invalid range list table index %d", Index);
649 return createStringError(errc::invalid_argument,
650 "missing or invalid range list table");
653 Expected<DWARFAddressRangesVector> DWARFUnit::collectAddressRanges() {
654 DWARFDie UnitDie = getUnitDIE();
656 return createStringError(errc::invalid_argument, "No unit DIE");
658 // First, check if unit DIE describes address ranges for the whole unit.
659 auto CUDIERangesOrError = UnitDie.getAddressRanges();
660 if (!CUDIERangesOrError)
661 return createStringError(errc::invalid_argument,
662 "decoding address ranges: %s",
663 toString(CUDIERangesOrError.takeError()).c_str());
664 return *CUDIERangesOrError;
667 Expected<DWARFLocationExpressionsVector>
668 DWARFUnit::findLoclistFromOffset(uint64_t Offset) {
669 DWARFLocationExpressionsVector Result;
671 Error InterpretationError = Error::success();
673 Error ParseError = getLocationTable().visitAbsoluteLocationList(
674 Offset, getBaseAddress(),
675 [this](uint32_t Index) { return getAddrOffsetSectionItem(Index); },
676 [&](Expected<DWARFLocationExpression> L) {
678 Result.push_back(std::move(*L));
680 InterpretationError =
681 joinErrors(L.takeError(), std::move(InterpretationError));
682 return !InterpretationError;
685 if (ParseError || InterpretationError)
686 return joinErrors(std::move(ParseError), std::move(InterpretationError));
691 void DWARFUnit::updateAddressDieMap(DWARFDie Die) {
692 if (Die.isSubroutineDIE()) {
693 auto DIERangesOrError = Die.getAddressRanges();
694 if (DIERangesOrError) {
695 for (const auto &R : DIERangesOrError.get()) {
696 // Ignore 0-sized ranges.
697 if (R.LowPC == R.HighPC)
699 auto B = AddrDieMap.upper_bound(R.LowPC);
700 if (B != AddrDieMap.begin() && R.LowPC < (--B)->second.first) {
701 // The range is a sub-range of existing ranges, we need to split the
703 if (R.HighPC < B->second.first)
704 AddrDieMap[R.HighPC] = B->second;
705 if (R.LowPC > B->first)
706 AddrDieMap[B->first].first = R.LowPC;
708 AddrDieMap[R.LowPC] = std::make_pair(R.HighPC, Die);
711 llvm::consumeError(DIERangesOrError.takeError());
713 // Parent DIEs are added to the AddrDieMap prior to the Children DIEs to
714 // simplify the logic to update AddrDieMap. The child's range will always
715 // be equal or smaller than the parent's range. With this assumption, when
716 // adding one range into the map, it will at most split a range into 3
718 for (DWARFDie Child = Die.getFirstChild(); Child; Child = Child.getSibling())
719 updateAddressDieMap(Child);
722 DWARFDie DWARFUnit::getSubroutineForAddress(uint64_t Address) {
723 extractDIEsIfNeeded(false);
724 if (AddrDieMap.empty())
725 updateAddressDieMap(getUnitDIE());
726 auto R = AddrDieMap.upper_bound(Address);
727 if (R == AddrDieMap.begin())
729 // upper_bound's previous item contains Address.
731 if (Address >= R->second.first)
733 return R->second.second;
737 DWARFUnit::getInlinedChainForAddress(uint64_t Address,
738 SmallVectorImpl<DWARFDie> &InlinedChain) {
739 assert(InlinedChain.empty());
740 // Try to look for subprogram DIEs in the DWO file.
742 // First, find the subroutine that contains the given address (the leaf
743 // of inlined chain).
744 DWARFDie SubroutineDIE =
745 (DWO ? *DWO : *this).getSubroutineForAddress(Address);
750 while (!SubroutineDIE.isSubprogramDIE()) {
751 if (SubroutineDIE.getTag() == DW_TAG_inlined_subroutine)
752 InlinedChain.push_back(SubroutineDIE);
753 SubroutineDIE = SubroutineDIE.getParent();
755 InlinedChain.push_back(SubroutineDIE);
758 const DWARFUnitIndex &llvm::getDWARFUnitIndex(DWARFContext &Context,
759 DWARFSectionKind Kind) {
760 if (Kind == DW_SECT_INFO)
761 return Context.getCUIndex();
762 assert(Kind == DW_SECT_TYPES);
763 return Context.getTUIndex();
766 DWARFDie DWARFUnit::getParent(const DWARFDebugInfoEntry *Die) {
769 const uint32_t Depth = Die->getDepth();
770 // Unit DIEs always have a depth of zero and never have parents.
773 // Depth of 1 always means parent is the compile/type unit.
776 // Look for previous DIE with a depth that is one less than the Die's depth.
777 const uint32_t ParentDepth = Depth - 1;
778 for (uint32_t I = getDIEIndex(Die) - 1; I > 0; --I) {
779 if (DieArray[I].getDepth() == ParentDepth)
780 return DWARFDie(this, &DieArray[I]);
785 DWARFDie DWARFUnit::getSibling(const DWARFDebugInfoEntry *Die) {
788 uint32_t Depth = Die->getDepth();
789 // Unit DIEs always have a depth of zero and never have siblings.
792 // NULL DIEs don't have siblings.
793 if (Die->getAbbreviationDeclarationPtr() == nullptr)
796 // Find the next DIE whose depth is the same as the Die's depth.
797 for (size_t I = getDIEIndex(Die) + 1, EndIdx = DieArray.size(); I < EndIdx;
799 if (DieArray[I].getDepth() == Depth)
800 return DWARFDie(this, &DieArray[I]);
805 DWARFDie DWARFUnit::getPreviousSibling(const DWARFDebugInfoEntry *Die) {
808 uint32_t Depth = Die->getDepth();
809 // Unit DIEs always have a depth of zero and never have siblings.
813 // Find the previous DIE whose depth is the same as the Die's depth.
814 for (size_t I = getDIEIndex(Die); I > 0;) {
816 if (DieArray[I].getDepth() == Depth - 1)
818 if (DieArray[I].getDepth() == Depth)
819 return DWARFDie(this, &DieArray[I]);
824 DWARFDie DWARFUnit::getFirstChild(const DWARFDebugInfoEntry *Die) {
825 if (!Die->hasChildren())
828 // We do not want access out of bounds when parsing corrupted debug data.
829 size_t I = getDIEIndex(Die) + 1;
830 if (I >= DieArray.size())
832 return DWARFDie(this, &DieArray[I]);
835 DWARFDie DWARFUnit::getLastChild(const DWARFDebugInfoEntry *Die) {
836 if (!Die->hasChildren())
839 uint32_t Depth = Die->getDepth();
840 for (size_t I = getDIEIndex(Die) + 1, EndIdx = DieArray.size(); I < EndIdx;
842 if (DieArray[I].getDepth() == Depth + 1 &&
843 DieArray[I].getTag() == dwarf::DW_TAG_null)
844 return DWARFDie(this, &DieArray[I]);
845 assert(DieArray[I].getDepth() > Depth && "Not processing children?");
850 const DWARFAbbreviationDeclarationSet *DWARFUnit::getAbbreviations() const {
852 Abbrevs = Abbrev->getAbbreviationDeclarationSet(Header.getAbbrOffset());
856 llvm::Optional<object::SectionedAddress> DWARFUnit::getBaseAddress() {
860 DWARFDie UnitDie = getUnitDIE();
861 Optional<DWARFFormValue> PC = UnitDie.find({DW_AT_low_pc, DW_AT_entry_pc});
862 BaseAddr = toSectionedAddress(PC);
866 Expected<StrOffsetsContributionDescriptor>
867 StrOffsetsContributionDescriptor::validateContributionSize(
868 DWARFDataExtractor &DA) {
869 uint8_t EntrySize = getDwarfOffsetByteSize();
870 // In order to ensure that we don't read a partial record at the end of
871 // the section we validate for a multiple of the entry size.
872 uint64_t ValidationSize = alignTo(Size, EntrySize);
873 // Guard against overflow.
874 if (ValidationSize >= Size)
875 if (DA.isValidOffsetForDataOfSize((uint32_t)Base, ValidationSize))
877 return createStringError(errc::invalid_argument, "length exceeds section size");
880 // Look for a DWARF64-formatted contribution to the string offsets table
881 // starting at a given offset and record it in a descriptor.
882 static Expected<StrOffsetsContributionDescriptor>
883 parseDWARF64StringOffsetsTableHeader(DWARFDataExtractor &DA, uint64_t Offset) {
884 if (!DA.isValidOffsetForDataOfSize(Offset, 16))
885 return createStringError(errc::invalid_argument, "section offset exceeds section size");
887 if (DA.getU32(&Offset) != dwarf::DW_LENGTH_DWARF64)
888 return createStringError(errc::invalid_argument, "32 bit contribution referenced from a 64 bit unit");
890 uint64_t Size = DA.getU64(&Offset);
891 uint8_t Version = DA.getU16(&Offset);
892 (void)DA.getU16(&Offset); // padding
893 // The encoded length includes the 2-byte version field and the 2-byte
894 // padding, so we need to subtract them out when we populate the descriptor.
895 return StrOffsetsContributionDescriptor(Offset, Size - 4, Version, DWARF64);
898 // Look for a DWARF32-formatted contribution to the string offsets table
899 // starting at a given offset and record it in a descriptor.
900 static Expected<StrOffsetsContributionDescriptor>
901 parseDWARF32StringOffsetsTableHeader(DWARFDataExtractor &DA, uint64_t Offset) {
902 if (!DA.isValidOffsetForDataOfSize(Offset, 8))
903 return createStringError(errc::invalid_argument, "section offset exceeds section size");
905 uint32_t ContributionSize = DA.getU32(&Offset);
906 if (ContributionSize >= dwarf::DW_LENGTH_lo_reserved)
907 return createStringError(errc::invalid_argument, "invalid length");
909 uint8_t Version = DA.getU16(&Offset);
910 (void)DA.getU16(&Offset); // padding
911 // The encoded length includes the 2-byte version field and the 2-byte
912 // padding, so we need to subtract them out when we populate the descriptor.
913 return StrOffsetsContributionDescriptor(Offset, ContributionSize - 4, Version,
917 static Expected<StrOffsetsContributionDescriptor>
918 parseDWARFStringOffsetsTableHeader(DWARFDataExtractor &DA,
919 llvm::dwarf::DwarfFormat Format,
921 StrOffsetsContributionDescriptor Desc;
923 case dwarf::DwarfFormat::DWARF64: {
925 return createStringError(errc::invalid_argument, "insufficient space for 64 bit header prefix");
926 auto DescOrError = parseDWARF64StringOffsetsTableHeader(DA, Offset - 16);
928 return DescOrError.takeError();
932 case dwarf::DwarfFormat::DWARF32: {
934 return createStringError(errc::invalid_argument, "insufficient space for 32 bit header prefix");
935 auto DescOrError = parseDWARF32StringOffsetsTableHeader(DA, Offset - 8);
937 return DescOrError.takeError();
942 return Desc.validateContributionSize(DA);
945 Expected<Optional<StrOffsetsContributionDescriptor>>
946 DWARFUnit::determineStringOffsetsTableContribution(DWARFDataExtractor &DA) {
950 if (DA.getData().data() == nullptr)
953 auto OptOffset = toSectionOffset(getUnitDIE().find(DW_AT_str_offsets_base));
958 auto DescOrError = parseDWARFStringOffsetsTableHeader(DA, Header.getFormat(), Offset);
960 return DescOrError.takeError();
964 Expected<Optional<StrOffsetsContributionDescriptor>>
965 DWARFUnit::determineStringOffsetsTableContributionDWO(DWARFDataExtractor & DA) {
967 auto IndexEntry = Header.getIndexEntry();
969 IndexEntry ? IndexEntry->getOffset(DW_SECT_STR_OFFSETS) : nullptr;
972 if (getVersion() >= 5) {
973 if (DA.getData().data() == nullptr)
975 Offset += Header.getFormat() == dwarf::DwarfFormat::DWARF32 ? 8 : 16;
976 // Look for a valid contribution at the given offset.
977 auto DescOrError = parseDWARFStringOffsetsTableHeader(DA, Header.getFormat(), Offset);
979 return DescOrError.takeError();
982 // Prior to DWARF v5, we derive the contribution size from the
983 // index table (in a package file). In a .dwo file it is simply
984 // the length of the string offsets section.
987 Optional<StrOffsetsContributionDescriptor>(
988 {0, StringOffsetSection.Data.size(), 4, DWARF32})};
990 return {Optional<StrOffsetsContributionDescriptor>(
991 {C->Offset, C->Length, 4, DWARF32})};