994 lines
		
	
	
		
			37 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			994 lines
		
	
	
		
			37 KiB
		
	
	
	
		
			C++
		
	
	
	
| //===- DWARFUnit.cpp ------------------------------------------------------===//
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| //
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| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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| // See https://llvm.org/LICENSE.txt for license information.
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| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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| //
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| //===----------------------------------------------------------------------===//
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| 
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| #include "llvm/DebugInfo/DWARF/DWARFUnit.h"
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| #include "llvm/ADT/SmallString.h"
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| #include "llvm/ADT/StringRef.h"
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| #include "llvm/DebugInfo/DWARF/DWARFAbbreviationDeclaration.h"
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| #include "llvm/DebugInfo/DWARF/DWARFCompileUnit.h"
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| #include "llvm/DebugInfo/DWARF/DWARFContext.h"
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| #include "llvm/DebugInfo/DWARF/DWARFDebugAbbrev.h"
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| #include "llvm/DebugInfo/DWARF/DWARFDebugInfoEntry.h"
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| #include "llvm/DebugInfo/DWARF/DWARFDebugRnglists.h"
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| #include "llvm/DebugInfo/DWARF/DWARFDie.h"
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| #include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
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| #include "llvm/DebugInfo/DWARF/DWARFTypeUnit.h"
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| #include "llvm/Support/DataExtractor.h"
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| #include "llvm/Support/Errc.h"
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| #include "llvm/Support/Path.h"
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| #include <algorithm>
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| #include <cassert>
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| #include <cstddef>
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| #include <cstdint>
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| #include <cstdio>
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| #include <utility>
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| #include <vector>
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| 
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| using namespace llvm;
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| using namespace dwarf;
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| 
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| void DWARFUnitVector::addUnitsForSection(DWARFContext &C,
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|                                          const DWARFSection &Section,
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|                                          DWARFSectionKind SectionKind) {
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|   const DWARFObject &D = C.getDWARFObj();
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|   addUnitsImpl(C, D, Section, C.getDebugAbbrev(), &D.getRangesSection(),
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|                &D.getLocSection(), D.getStrSection(),
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|                D.getStrOffsetsSection(), &D.getAddrSection(),
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|                D.getLineSection(), D.isLittleEndian(), false, false,
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|                SectionKind);
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| }
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| 
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| void DWARFUnitVector::addUnitsForDWOSection(DWARFContext &C,
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|                                             const DWARFSection &DWOSection,
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|                                             DWARFSectionKind SectionKind,
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|                                             bool Lazy) {
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|   const DWARFObject &D = C.getDWARFObj();
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|   addUnitsImpl(C, D, DWOSection, C.getDebugAbbrevDWO(), &D.getRangesDWOSection(),
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|                &D.getLocDWOSection(), D.getStrDWOSection(),
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|                D.getStrOffsetsDWOSection(), &D.getAddrSection(),
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|                D.getLineDWOSection(), C.isLittleEndian(), true, Lazy,
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|                SectionKind);
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| }
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| 
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| void DWARFUnitVector::addUnitsImpl(
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|     DWARFContext &Context, const DWARFObject &Obj, const DWARFSection &Section,
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|     const DWARFDebugAbbrev *DA, const DWARFSection *RS,
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|     const DWARFSection *LocSection, StringRef SS, const DWARFSection &SOS,
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|     const DWARFSection *AOS, const DWARFSection &LS, bool LE, bool IsDWO,
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|     bool Lazy, DWARFSectionKind SectionKind) {
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|   DWARFDataExtractor Data(Obj, Section, LE, 0);
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|   // Lazy initialization of Parser, now that we have all section info.
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|   if (!Parser) {
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|     Parser = [=, &Context, &Obj, &Section, &SOS,
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|               &LS](uint64_t Offset, DWARFSectionKind SectionKind,
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|                    const DWARFSection *CurSection,
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|                    const DWARFUnitIndex::Entry *IndexEntry)
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|         -> std::unique_ptr<DWARFUnit> {
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|       const DWARFSection &InfoSection = CurSection ? *CurSection : Section;
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|       DWARFDataExtractor Data(Obj, InfoSection, LE, 0);
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|       if (!Data.isValidOffset(Offset))
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|         return nullptr;
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|       const DWARFUnitIndex *Index = nullptr;
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|       if (IsDWO)
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|         Index = &getDWARFUnitIndex(Context, SectionKind);
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|       DWARFUnitHeader Header;
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|       if (!Header.extract(Context, Data, &Offset, SectionKind, Index,
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|                           IndexEntry))
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|         return nullptr;
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|       std::unique_ptr<DWARFUnit> U;
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|       if (Header.isTypeUnit())
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|         U = std::make_unique<DWARFTypeUnit>(Context, InfoSection, Header, DA,
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|                                              RS, LocSection, SS, SOS, AOS, LS,
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|                                              LE, IsDWO, *this);
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|       else
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|         U = std::make_unique<DWARFCompileUnit>(Context, InfoSection, Header,
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|                                                 DA, RS, LocSection, SS, SOS,
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|                                                 AOS, LS, LE, IsDWO, *this);
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|       return U;
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|     };
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|   }
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|   if (Lazy)
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|     return;
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|   // Find a reasonable insertion point within the vector.  We skip over
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|   // (a) units from a different section, (b) units from the same section
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|   // but with lower offset-within-section.  This keeps units in order
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|   // within a section, although not necessarily within the object file,
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|   // even if we do lazy parsing.
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|   auto I = this->begin();
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|   uint64_t Offset = 0;
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|   while (Data.isValidOffset(Offset)) {
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|     if (I != this->end() &&
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|         (&(*I)->getInfoSection() != &Section || (*I)->getOffset() == Offset)) {
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|       ++I;
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|       continue;
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|     }
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|     auto U = Parser(Offset, SectionKind, &Section, nullptr);
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|     // If parsing failed, we're done with this section.
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|     if (!U)
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|       break;
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|     Offset = U->getNextUnitOffset();
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|     I = std::next(this->insert(I, std::move(U)));
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|   }
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| }
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| 
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| DWARFUnit *DWARFUnitVector::addUnit(std::unique_ptr<DWARFUnit> Unit) {
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|   auto I = std::upper_bound(begin(), end(), Unit,
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|                             [](const std::unique_ptr<DWARFUnit> &LHS,
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|                                const std::unique_ptr<DWARFUnit> &RHS) {
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|                               return LHS->getOffset() < RHS->getOffset();
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|                             });
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|   return this->insert(I, std::move(Unit))->get();
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| }
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| 
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| DWARFUnit *DWARFUnitVector::getUnitForOffset(uint64_t Offset) const {
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|   auto end = begin() + getNumInfoUnits();
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|   auto *CU =
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|       std::upper_bound(begin(), end, Offset,
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|                        [](uint64_t LHS, const std::unique_ptr<DWARFUnit> &RHS) {
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|                          return LHS < RHS->getNextUnitOffset();
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|                        });
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|   if (CU != end && (*CU)->getOffset() <= Offset)
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|     return CU->get();
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|   return nullptr;
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| }
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| 
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| DWARFUnit *
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| DWARFUnitVector::getUnitForIndexEntry(const DWARFUnitIndex::Entry &E) {
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|   const auto *CUOff = E.getOffset(DW_SECT_INFO);
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|   if (!CUOff)
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|     return nullptr;
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| 
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|   auto Offset = CUOff->Offset;
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|   auto end = begin() + getNumInfoUnits();
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| 
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|   auto *CU =
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|       std::upper_bound(begin(), end, CUOff->Offset,
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|                        [](uint64_t LHS, const std::unique_ptr<DWARFUnit> &RHS) {
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|                          return LHS < RHS->getNextUnitOffset();
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|                        });
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|   if (CU != end && (*CU)->getOffset() <= Offset)
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|     return CU->get();
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| 
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|   if (!Parser)
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|     return nullptr;
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| 
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|   auto U = Parser(Offset, DW_SECT_INFO, nullptr, &E);
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|   if (!U)
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|     U = nullptr;
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| 
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|   auto *NewCU = U.get();
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|   this->insert(CU, std::move(U));
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|   ++NumInfoUnits;
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|   return NewCU;
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| }
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| 
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| DWARFUnit::DWARFUnit(DWARFContext &DC, const DWARFSection &Section,
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|                      const DWARFUnitHeader &Header, const DWARFDebugAbbrev *DA,
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|                      const DWARFSection *RS, const DWARFSection *LocSection,
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|                      StringRef SS, const DWARFSection &SOS,
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|                      const DWARFSection *AOS, const DWARFSection &LS, bool LE,
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|                      bool IsDWO, const DWARFUnitVector &UnitVector)
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|     : Context(DC), InfoSection(Section), Header(Header), Abbrev(DA),
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|       RangeSection(RS), LineSection(LS), StringSection(SS),
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|       StringOffsetSection(SOS), AddrOffsetSection(AOS), isLittleEndian(LE),
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|       IsDWO(IsDWO), UnitVector(UnitVector) {
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|   clear();
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|   if (IsDWO) {
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|     // If we are reading a package file, we need to adjust the location list
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|     // data based on the index entries.
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|     StringRef Data = LocSection->Data;
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|     if (auto *IndexEntry = Header.getIndexEntry())
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|       if (const auto *C = IndexEntry->getOffset(DW_SECT_LOC))
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|         Data = Data.substr(C->Offset, C->Length);
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| 
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|     DWARFDataExtractor DWARFData =
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|         Header.getVersion() >= 5
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|             ? DWARFDataExtractor(Context.getDWARFObj(),
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|                                  Context.getDWARFObj().getLoclistsDWOSection(),
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|                                  isLittleEndian, getAddressByteSize())
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|             : DWARFDataExtractor(Data, isLittleEndian, getAddressByteSize());
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|     LocTable =
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|         std::make_unique<DWARFDebugLoclists>(DWARFData, Header.getVersion());
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| 
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|   } else if (Header.getVersion() >= 5) {
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|     LocTable = std::make_unique<DWARFDebugLoclists>(
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|         DWARFDataExtractor(Context.getDWARFObj(),
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|                            Context.getDWARFObj().getLoclistsSection(),
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|                            isLittleEndian, getAddressByteSize()),
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|         Header.getVersion());
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|   } else {
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|     LocTable = std::make_unique<DWARFDebugLoc>(
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|         DWARFDataExtractor(Context.getDWARFObj(), *LocSection, isLittleEndian,
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|                            getAddressByteSize()));
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|   }
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| }
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| 
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| DWARFUnit::~DWARFUnit() = default;
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| 
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| DWARFDataExtractor DWARFUnit::getDebugInfoExtractor() const {
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|   return DWARFDataExtractor(Context.getDWARFObj(), InfoSection, isLittleEndian,
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|                             getAddressByteSize());
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| }
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| 
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| Optional<object::SectionedAddress>
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| DWARFUnit::getAddrOffsetSectionItem(uint32_t Index) const {
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|   if (IsDWO) {
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|     auto R = Context.info_section_units();
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|     auto I = R.begin();
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|     // Surprising if a DWO file has more than one skeleton unit in it - this
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|     // probably shouldn't be valid, but if a use case is found, here's where to
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|     // support it (probably have to linearly search for the matching skeleton CU
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|     // here)
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|     if (I != R.end() && std::next(I) == R.end())
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|       return (*I)->getAddrOffsetSectionItem(Index);
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|   }
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|   if (!AddrOffsetSectionBase)
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|     return None;
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|   uint64_t Offset = *AddrOffsetSectionBase + Index * getAddressByteSize();
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|   if (AddrOffsetSection->Data.size() < Offset + getAddressByteSize())
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|     return None;
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|   DWARFDataExtractor DA(Context.getDWARFObj(), *AddrOffsetSection,
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|                         isLittleEndian, getAddressByteSize());
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|   uint64_t Section;
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|   uint64_t Address = DA.getRelocatedAddress(&Offset, &Section);
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|   return {{Address, Section}};
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| }
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| 
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| Optional<uint64_t> DWARFUnit::getStringOffsetSectionItem(uint32_t Index) const {
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|   if (!StringOffsetsTableContribution)
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|     return None;
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|   unsigned ItemSize = getDwarfStringOffsetsByteSize();
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|   uint64_t Offset = getStringOffsetsBase() + Index * ItemSize;
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|   if (StringOffsetSection.Data.size() < Offset + ItemSize)
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|     return None;
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|   DWARFDataExtractor DA(Context.getDWARFObj(), StringOffsetSection,
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|                         isLittleEndian, 0);
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|   return DA.getRelocatedValue(ItemSize, &Offset);
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| }
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| 
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| bool DWARFUnitHeader::extract(DWARFContext &Context,
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|                               const DWARFDataExtractor &debug_info,
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|                               uint64_t *offset_ptr,
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|                               DWARFSectionKind SectionKind,
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|                               const DWARFUnitIndex *Index,
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|                               const DWARFUnitIndex::Entry *Entry) {
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|   Offset = *offset_ptr;
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|   Error Err = Error::success();
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|   IndexEntry = Entry;
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|   if (!IndexEntry && Index)
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|     IndexEntry = Index->getFromOffset(*offset_ptr);
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|   std::tie(Length, FormParams.Format) =
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|       debug_info.getInitialLength(offset_ptr, &Err);
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|   FormParams.Version = debug_info.getU16(offset_ptr, &Err);
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|   if (FormParams.Version >= 5) {
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|     UnitType = debug_info.getU8(offset_ptr, &Err);
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|     FormParams.AddrSize = debug_info.getU8(offset_ptr, &Err);
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|     AbbrOffset = debug_info.getRelocatedValue(
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|         FormParams.getDwarfOffsetByteSize(), offset_ptr, nullptr, &Err);
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|   } else {
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|     AbbrOffset = debug_info.getRelocatedValue(
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|         FormParams.getDwarfOffsetByteSize(), offset_ptr, nullptr, &Err);
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|     FormParams.AddrSize = debug_info.getU8(offset_ptr, &Err);
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|     // Fake a unit type based on the section type.  This isn't perfect,
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|     // but distinguishing compile and type units is generally enough.
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|     if (SectionKind == DW_SECT_TYPES)
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|       UnitType = DW_UT_type;
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|     else
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|       UnitType = DW_UT_compile;
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|   }
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|   if (isTypeUnit()) {
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|     TypeHash = debug_info.getU64(offset_ptr, &Err);
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|     TypeOffset = debug_info.getUnsigned(
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|         offset_ptr, FormParams.getDwarfOffsetByteSize(), &Err);
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|   } else if (UnitType == DW_UT_split_compile || UnitType == DW_UT_skeleton)
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|     DWOId = debug_info.getU64(offset_ptr, &Err);
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| 
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|   if (errorToBool(std::move(Err)))
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|     return false;
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| 
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|   if (IndexEntry) {
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|     if (AbbrOffset)
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|       return false;
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|     auto *UnitContrib = IndexEntry->getOffset();
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|     if (!UnitContrib ||
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|         UnitContrib->Length != (Length + getUnitLengthFieldByteSize()))
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|       return false;
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|     auto *AbbrEntry = IndexEntry->getOffset(DW_SECT_ABBREV);
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|     if (!AbbrEntry)
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|       return false;
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|     AbbrOffset = AbbrEntry->Offset;
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|   }
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| 
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|   // Header fields all parsed, capture the size of this unit header.
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|   assert(*offset_ptr - Offset <= 255 && "unexpected header size");
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|   Size = uint8_t(*offset_ptr - Offset);
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| 
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|   // Type offset is unit-relative; should be after the header and before
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|   // the end of the current unit.
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|   bool TypeOffsetOK =
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|       !isTypeUnit()
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|           ? true
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|           : TypeOffset >= Size &&
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|                 TypeOffset < getLength() + getUnitLengthFieldByteSize();
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|   bool LengthOK = debug_info.isValidOffset(getNextUnitOffset() - 1);
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|   bool VersionOK = DWARFContext::isSupportedVersion(getVersion());
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|   bool AddrSizeOK = getAddressByteSize() == 4 || getAddressByteSize() == 8;
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| 
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|   if (!LengthOK || !VersionOK || !AddrSizeOK || !TypeOffsetOK)
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|     return false;
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| 
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|   // Keep track of the highest DWARF version we encounter across all units.
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|   Context.setMaxVersionIfGreater(getVersion());
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|   return true;
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| }
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| 
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| // Parse the rangelist table header, including the optional array of offsets
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| // following it (DWARF v5 and later).
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| template<typename ListTableType>
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| static Expected<ListTableType>
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| parseListTableHeader(DWARFDataExtractor &DA, uint64_t Offset,
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|                         DwarfFormat Format) {
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|   // We are expected to be called with Offset 0 or pointing just past the table
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|   // header. Correct Offset in the latter case so that it points to the start
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|   // of the header.
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|   if (Offset > 0) {
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|     uint64_t HeaderSize = DWARFListTableHeader::getHeaderSize(Format);
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|     if (Offset < HeaderSize)
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|       return createStringError(errc::invalid_argument, "did not detect a valid"
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|                                " list table with base = 0x%" PRIx64 "\n",
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|                                Offset);
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|     Offset -= HeaderSize;
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|   }
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|   ListTableType Table;
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|   if (Error E = Table.extractHeaderAndOffsets(DA, &Offset))
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|     return std::move(E);
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|   return Table;
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| }
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| 
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| Error DWARFUnit::extractRangeList(uint64_t RangeListOffset,
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|                                   DWARFDebugRangeList &RangeList) const {
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|   // Require that compile unit is extracted.
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|   assert(!DieArray.empty());
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|   DWARFDataExtractor RangesData(Context.getDWARFObj(), *RangeSection,
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|                                 isLittleEndian, getAddressByteSize());
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|   uint64_t ActualRangeListOffset = RangeSectionBase + RangeListOffset;
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|   return RangeList.extract(RangesData, &ActualRangeListOffset);
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| }
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| 
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| void DWARFUnit::clear() {
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|   Abbrevs = nullptr;
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|   BaseAddr.reset();
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|   RangeSectionBase = 0;
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|   LocSectionBase = 0;
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|   AddrOffsetSectionBase = None;
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|   clearDIEs(false);
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|   DWO.reset();
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| }
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| 
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| const char *DWARFUnit::getCompilationDir() {
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|   return dwarf::toString(getUnitDIE().find(DW_AT_comp_dir), nullptr);
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| }
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| 
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| void DWARFUnit::extractDIEsToVector(
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|     bool AppendCUDie, bool AppendNonCUDies,
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|     std::vector<DWARFDebugInfoEntry> &Dies) const {
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|   if (!AppendCUDie && !AppendNonCUDies)
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|     return;
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| 
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|   // Set the offset to that of the first DIE and calculate the start of the
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|   // next compilation unit header.
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|   uint64_t DIEOffset = getOffset() + getHeaderSize();
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|   uint64_t NextCUOffset = getNextUnitOffset();
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|   DWARFDebugInfoEntry DIE;
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|   DWARFDataExtractor DebugInfoData = getDebugInfoExtractor();
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|   uint32_t Depth = 0;
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|   bool IsCUDie = true;
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| 
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|   while (DIE.extractFast(*this, &DIEOffset, DebugInfoData, NextCUOffset,
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|                          Depth)) {
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|     if (IsCUDie) {
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|       if (AppendCUDie)
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|         Dies.push_back(DIE);
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|       if (!AppendNonCUDies)
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|         break;
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|       // The average bytes per DIE entry has been seen to be
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|       // around 14-20 so let's pre-reserve the needed memory for
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|       // our DIE entries accordingly.
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|       Dies.reserve(Dies.size() + getDebugInfoSize() / 14);
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|       IsCUDie = false;
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|     } else {
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|       Dies.push_back(DIE);
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|     }
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| 
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|     if (const DWARFAbbreviationDeclaration *AbbrDecl =
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|             DIE.getAbbreviationDeclarationPtr()) {
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|       // Normal DIE
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|       if (AbbrDecl->hasChildren())
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|         ++Depth;
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|     } else {
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|       // NULL DIE.
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|       if (Depth > 0)
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|         --Depth;
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|       if (Depth == 0)
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|         break;  // We are done with this compile unit!
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|     }
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|   }
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| 
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|   // Give a little bit of info if we encounter corrupt DWARF (our offset
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|   // should always terminate at or before the start of the next compilation
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|   // unit header).
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|   if (DIEOffset > NextCUOffset)
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|     Context.getWarningHandler()(
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|         createStringError(errc::invalid_argument,
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|                           "DWARF compile unit extends beyond its "
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|                           "bounds cu 0x%8.8" PRIx64 " "
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|                           "at 0x%8.8" PRIx64 "\n",
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|                           getOffset(), DIEOffset));
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| }
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| 
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| void DWARFUnit::extractDIEsIfNeeded(bool CUDieOnly) {
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|   if (Error e = tryExtractDIEsIfNeeded(CUDieOnly))
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|     Context.getRecoverableErrorHandler()(std::move(e));
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| }
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| 
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| Error DWARFUnit::tryExtractDIEsIfNeeded(bool CUDieOnly) {
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|   if ((CUDieOnly && !DieArray.empty()) ||
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|       DieArray.size() > 1)
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|     return Error::success(); // Already parsed.
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| 
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|   bool HasCUDie = !DieArray.empty();
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|   extractDIEsToVector(!HasCUDie, !CUDieOnly, DieArray);
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| 
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|   if (DieArray.empty())
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|     return Error::success();
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| 
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|   // If CU DIE was just parsed, copy several attribute values from it.
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|   if (HasCUDie)
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|     return Error::success();
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| 
 | |
|   DWARFDie UnitDie(this, &DieArray[0]);
 | |
|   if (Optional<uint64_t> DWOId = toUnsigned(UnitDie.find(DW_AT_GNU_dwo_id)))
 | |
|     Header.setDWOId(*DWOId);
 | |
|   if (!IsDWO) {
 | |
|     assert(AddrOffsetSectionBase == None);
 | |
|     assert(RangeSectionBase == 0);
 | |
|     assert(LocSectionBase == 0);
 | |
|     AddrOffsetSectionBase = toSectionOffset(UnitDie.find(DW_AT_addr_base));
 | |
|     if (!AddrOffsetSectionBase)
 | |
|       AddrOffsetSectionBase =
 | |
|           toSectionOffset(UnitDie.find(DW_AT_GNU_addr_base));
 | |
|     RangeSectionBase = toSectionOffset(UnitDie.find(DW_AT_rnglists_base), 0);
 | |
|     LocSectionBase = toSectionOffset(UnitDie.find(DW_AT_loclists_base), 0);
 | |
|   }
 | |
| 
 | |
|   // In general, in DWARF v5 and beyond we derive the start of the unit's
 | |
|   // contribution to the string offsets table from the unit DIE's
 | |
|   // DW_AT_str_offsets_base attribute. Split DWARF units do not use this
 | |
|   // attribute, so we assume that there is a contribution to the string
 | |
|   // offsets table starting at offset 0 of the debug_str_offsets.dwo section.
 | |
|   // In both cases we need to determine the format of the contribution,
 | |
|   // which may differ from the unit's format.
 | |
|   DWARFDataExtractor DA(Context.getDWARFObj(), StringOffsetSection,
 | |
|                         isLittleEndian, 0);
 | |
|   if (IsDWO || getVersion() >= 5) {
 | |
|     auto StringOffsetOrError =
 | |
|         IsDWO ? determineStringOffsetsTableContributionDWO(DA)
 | |
|               : determineStringOffsetsTableContribution(DA);
 | |
|     if (!StringOffsetOrError)
 | |
|       return createStringError(errc::invalid_argument,
 | |
|                                "invalid reference to or invalid content in "
 | |
|                                ".debug_str_offsets[.dwo]: " +
 | |
|                                    toString(StringOffsetOrError.takeError()));
 | |
| 
 | |
|     StringOffsetsTableContribution = *StringOffsetOrError;
 | |
|   }
 | |
| 
 | |
|   // DWARF v5 uses the .debug_rnglists and .debug_rnglists.dwo sections to
 | |
|   // describe address ranges.
 | |
|   if (getVersion() >= 5) {
 | |
|     if (IsDWO)
 | |
|       setRangesSection(&Context.getDWARFObj().getRnglistsDWOSection(), 0);
 | |
|     else
 | |
|       setRangesSection(&Context.getDWARFObj().getRnglistsSection(),
 | |
|                        toSectionOffset(UnitDie.find(DW_AT_rnglists_base), 0));
 | |
|     if (RangeSection->Data.size()) {
 | |
|       // Parse the range list table header. Individual range lists are
 | |
|       // extracted lazily.
 | |
|       DWARFDataExtractor RangesDA(Context.getDWARFObj(), *RangeSection,
 | |
|                                   isLittleEndian, 0);
 | |
|       auto TableOrError = parseListTableHeader<DWARFDebugRnglistTable>(
 | |
|           RangesDA, RangeSectionBase, Header.getFormat());
 | |
|       if (!TableOrError)
 | |
|         return createStringError(errc::invalid_argument,
 | |
|                                  "parsing a range list table: " +
 | |
|                                      toString(TableOrError.takeError()));
 | |
| 
 | |
|       RngListTable = TableOrError.get();
 | |
| 
 | |
|       // In a split dwarf unit, there is no DW_AT_rnglists_base attribute.
 | |
|       // Adjust RangeSectionBase to point past the table header.
 | |
|       if (IsDWO && RngListTable)
 | |
|         RangeSectionBase = RngListTable->getHeaderSize();
 | |
|     }
 | |
| 
 | |
|     // In a split dwarf unit, there is no DW_AT_loclists_base attribute.
 | |
|     // Setting LocSectionBase to point past the table header.
 | |
|     if (IsDWO)
 | |
|       setLocSection(&Context.getDWARFObj().getLoclistsDWOSection(),
 | |
|                     DWARFListTableHeader::getHeaderSize(Header.getFormat()));
 | |
|     else
 | |
|       setLocSection(&Context.getDWARFObj().getLoclistsSection(),
 | |
|                     toSectionOffset(UnitDie.find(DW_AT_loclists_base), 0));
 | |
| 
 | |
|     if (LocSection->Data.size()) {
 | |
|       if (IsDWO)
 | |
|         LoclistTableHeader.emplace(".debug_loclists.dwo", "locations");
 | |
|       else
 | |
|         LoclistTableHeader.emplace(".debug_loclists", "locations");
 | |
| 
 | |
|       uint64_t HeaderSize = DWARFListTableHeader::getHeaderSize(Header.getFormat());
 | |
|       uint64_t Offset = getLocSectionBase();
 | |
|       DWARFDataExtractor Data(Context.getDWARFObj(), *LocSection,
 | |
|                               isLittleEndian, getAddressByteSize());
 | |
|       if (Offset < HeaderSize)
 | |
|         return createStringError(errc::invalid_argument,
 | |
|                                  "did not detect a valid"
 | |
|                                  " list table with base = 0x%" PRIx64 "\n",
 | |
|                                  Offset);
 | |
|       Offset -= HeaderSize;
 | |
|       if (Error E = LoclistTableHeader->extract(Data, &Offset))
 | |
|         return createStringError(errc::invalid_argument,
 | |
|                                  "parsing a loclist table: " +
 | |
|                                      toString(std::move(E)));
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   // Don't fall back to DW_AT_GNU_ranges_base: it should be ignored for
 | |
|   // skeleton CU DIE, so that DWARF users not aware of it are not broken.
 | |
|   return Error::success();
 | |
| }
 | |
| 
 | |
| bool DWARFUnit::parseDWO() {
 | |
|   if (IsDWO)
 | |
|     return false;
 | |
|   if (DWO.get())
 | |
|     return false;
 | |
|   DWARFDie UnitDie = getUnitDIE();
 | |
|   if (!UnitDie)
 | |
|     return false;
 | |
|   auto DWOFileName = getVersion() >= 5
 | |
|                          ? dwarf::toString(UnitDie.find(DW_AT_dwo_name))
 | |
|                          : dwarf::toString(UnitDie.find(DW_AT_GNU_dwo_name));
 | |
|   if (!DWOFileName)
 | |
|     return false;
 | |
|   auto CompilationDir = dwarf::toString(UnitDie.find(DW_AT_comp_dir));
 | |
|   SmallString<16> AbsolutePath;
 | |
|   if (sys::path::is_relative(*DWOFileName) && CompilationDir &&
 | |
|       *CompilationDir) {
 | |
|     sys::path::append(AbsolutePath, *CompilationDir);
 | |
|   }
 | |
|   sys::path::append(AbsolutePath, *DWOFileName);
 | |
|   auto DWOId = getDWOId();
 | |
|   if (!DWOId)
 | |
|     return false;
 | |
|   auto DWOContext = Context.getDWOContext(AbsolutePath);
 | |
|   if (!DWOContext)
 | |
|     return false;
 | |
| 
 | |
|   DWARFCompileUnit *DWOCU = DWOContext->getDWOCompileUnitForHash(*DWOId);
 | |
|   if (!DWOCU)
 | |
|     return false;
 | |
|   DWO = std::shared_ptr<DWARFCompileUnit>(std::move(DWOContext), DWOCU);
 | |
|   // Share .debug_addr and .debug_ranges section with compile unit in .dwo
 | |
|   if (AddrOffsetSectionBase)
 | |
|     DWO->setAddrOffsetSection(AddrOffsetSection, *AddrOffsetSectionBase);
 | |
|   if (getVersion() >= 5) {
 | |
|     DWO->setRangesSection(&Context.getDWARFObj().getRnglistsDWOSection(), 0);
 | |
|     DWARFDataExtractor RangesDA(Context.getDWARFObj(), *RangeSection,
 | |
|                                 isLittleEndian, 0);
 | |
|     if (auto TableOrError = parseListTableHeader<DWARFDebugRnglistTable>(
 | |
|             RangesDA, RangeSectionBase, Header.getFormat()))
 | |
|       DWO->RngListTable = TableOrError.get();
 | |
|     else
 | |
|       Context.getRecoverableErrorHandler()(createStringError(
 | |
|           errc::invalid_argument, "parsing a range list table: %s",
 | |
|           toString(TableOrError.takeError()).c_str()));
 | |
| 
 | |
|     if (DWO->RngListTable)
 | |
|       DWO->RangeSectionBase = DWO->RngListTable->getHeaderSize();
 | |
|   } else {
 | |
|     auto DWORangesBase = UnitDie.getRangesBaseAttribute();
 | |
|     DWO->setRangesSection(RangeSection, DWORangesBase ? *DWORangesBase : 0);
 | |
|   }
 | |
| 
 | |
|   return true;
 | |
| }
 | |
| 
 | |
| void DWARFUnit::clearDIEs(bool KeepCUDie) {
 | |
|   if (DieArray.size() > (unsigned)KeepCUDie) {
 | |
|     DieArray.resize((unsigned)KeepCUDie);
 | |
|     DieArray.shrink_to_fit();
 | |
|   }
 | |
| }
 | |
| 
 | |
| Expected<DWARFAddressRangesVector>
 | |
| DWARFUnit::findRnglistFromOffset(uint64_t Offset) {
 | |
|   if (getVersion() <= 4) {
 | |
|     DWARFDebugRangeList RangeList;
 | |
|     if (Error E = extractRangeList(Offset, RangeList))
 | |
|       return std::move(E);
 | |
|     return RangeList.getAbsoluteRanges(getBaseAddress());
 | |
|   }
 | |
|   if (RngListTable) {
 | |
|     DWARFDataExtractor RangesData(Context.getDWARFObj(), *RangeSection,
 | |
|                                   isLittleEndian, RngListTable->getAddrSize());
 | |
|     auto RangeListOrError = RngListTable->findList(RangesData, Offset);
 | |
|     if (RangeListOrError)
 | |
|       return RangeListOrError.get().getAbsoluteRanges(getBaseAddress(), *this);
 | |
|     return RangeListOrError.takeError();
 | |
|   }
 | |
| 
 | |
|   return createStringError(errc::invalid_argument,
 | |
|                            "missing or invalid range list table");
 | |
| }
 | |
| 
 | |
| Expected<DWARFAddressRangesVector>
 | |
| DWARFUnit::findRnglistFromIndex(uint32_t Index) {
 | |
|   if (auto Offset = getRnglistOffset(Index))
 | |
|     return findRnglistFromOffset(*Offset);
 | |
| 
 | |
|   if (RngListTable)
 | |
|     return createStringError(errc::invalid_argument,
 | |
|                              "invalid range list table index %d", Index);
 | |
| 
 | |
|   return createStringError(errc::invalid_argument,
 | |
|                            "missing or invalid range list table");
 | |
| }
 | |
| 
 | |
| Expected<DWARFAddressRangesVector> DWARFUnit::collectAddressRanges() {
 | |
|   DWARFDie UnitDie = getUnitDIE();
 | |
|   if (!UnitDie)
 | |
|     return createStringError(errc::invalid_argument, "No unit DIE");
 | |
| 
 | |
|   // First, check if unit DIE describes address ranges for the whole unit.
 | |
|   auto CUDIERangesOrError = UnitDie.getAddressRanges();
 | |
|   if (!CUDIERangesOrError)
 | |
|     return createStringError(errc::invalid_argument,
 | |
|                              "decoding address ranges: %s",
 | |
|                              toString(CUDIERangesOrError.takeError()).c_str());
 | |
|   return *CUDIERangesOrError;
 | |
| }
 | |
| 
 | |
| Expected<DWARFLocationExpressionsVector>
 | |
| DWARFUnit::findLoclistFromOffset(uint64_t Offset) {
 | |
|   DWARFLocationExpressionsVector Result;
 | |
| 
 | |
|   Error InterpretationError = Error::success();
 | |
| 
 | |
|   Error ParseError = getLocationTable().visitAbsoluteLocationList(
 | |
|       Offset, getBaseAddress(),
 | |
|       [this](uint32_t Index) { return getAddrOffsetSectionItem(Index); },
 | |
|       [&](Expected<DWARFLocationExpression> L) {
 | |
|         if (L)
 | |
|           Result.push_back(std::move(*L));
 | |
|         else
 | |
|           InterpretationError =
 | |
|               joinErrors(L.takeError(), std::move(InterpretationError));
 | |
|         return !InterpretationError;
 | |
|       });
 | |
| 
 | |
|   if (ParseError || InterpretationError)
 | |
|     return joinErrors(std::move(ParseError), std::move(InterpretationError));
 | |
| 
 | |
|   return Result;
 | |
| }
 | |
| 
 | |
| void DWARFUnit::updateAddressDieMap(DWARFDie Die) {
 | |
|   if (Die.isSubroutineDIE()) {
 | |
|     auto DIERangesOrError = Die.getAddressRanges();
 | |
|     if (DIERangesOrError) {
 | |
|       for (const auto &R : DIERangesOrError.get()) {
 | |
|         // Ignore 0-sized ranges.
 | |
|         if (R.LowPC == R.HighPC)
 | |
|           continue;
 | |
|         auto B = AddrDieMap.upper_bound(R.LowPC);
 | |
|         if (B != AddrDieMap.begin() && R.LowPC < (--B)->second.first) {
 | |
|           // The range is a sub-range of existing ranges, we need to split the
 | |
|           // existing range.
 | |
|           if (R.HighPC < B->second.first)
 | |
|             AddrDieMap[R.HighPC] = B->second;
 | |
|           if (R.LowPC > B->first)
 | |
|             AddrDieMap[B->first].first = R.LowPC;
 | |
|         }
 | |
|         AddrDieMap[R.LowPC] = std::make_pair(R.HighPC, Die);
 | |
|       }
 | |
|     } else
 | |
|       llvm::consumeError(DIERangesOrError.takeError());
 | |
|   }
 | |
|   // Parent DIEs are added to the AddrDieMap prior to the Children DIEs to
 | |
|   // simplify the logic to update AddrDieMap. The child's range will always
 | |
|   // be equal or smaller than the parent's range. With this assumption, when
 | |
|   // adding one range into the map, it will at most split a range into 3
 | |
|   // sub-ranges.
 | |
|   for (DWARFDie Child = Die.getFirstChild(); Child; Child = Child.getSibling())
 | |
|     updateAddressDieMap(Child);
 | |
| }
 | |
| 
 | |
| DWARFDie DWARFUnit::getSubroutineForAddress(uint64_t Address) {
 | |
|   extractDIEsIfNeeded(false);
 | |
|   if (AddrDieMap.empty())
 | |
|     updateAddressDieMap(getUnitDIE());
 | |
|   auto R = AddrDieMap.upper_bound(Address);
 | |
|   if (R == AddrDieMap.begin())
 | |
|     return DWARFDie();
 | |
|   // upper_bound's previous item contains Address.
 | |
|   --R;
 | |
|   if (Address >= R->second.first)
 | |
|     return DWARFDie();
 | |
|   return R->second.second;
 | |
| }
 | |
| 
 | |
| void
 | |
| DWARFUnit::getInlinedChainForAddress(uint64_t Address,
 | |
|                                      SmallVectorImpl<DWARFDie> &InlinedChain) {
 | |
|   assert(InlinedChain.empty());
 | |
|   // Try to look for subprogram DIEs in the DWO file.
 | |
|   parseDWO();
 | |
|   // First, find the subroutine that contains the given address (the leaf
 | |
|   // of inlined chain).
 | |
|   DWARFDie SubroutineDIE =
 | |
|       (DWO ? *DWO : *this).getSubroutineForAddress(Address);
 | |
| 
 | |
|   if (!SubroutineDIE)
 | |
|     return;
 | |
| 
 | |
|   while (!SubroutineDIE.isSubprogramDIE()) {
 | |
|     if (SubroutineDIE.getTag() == DW_TAG_inlined_subroutine)
 | |
|       InlinedChain.push_back(SubroutineDIE);
 | |
|     SubroutineDIE  = SubroutineDIE.getParent();
 | |
|   }
 | |
|   InlinedChain.push_back(SubroutineDIE);
 | |
| }
 | |
| 
 | |
| const DWARFUnitIndex &llvm::getDWARFUnitIndex(DWARFContext &Context,
 | |
|                                               DWARFSectionKind Kind) {
 | |
|   if (Kind == DW_SECT_INFO)
 | |
|     return Context.getCUIndex();
 | |
|   assert(Kind == DW_SECT_TYPES);
 | |
|   return Context.getTUIndex();
 | |
| }
 | |
| 
 | |
| DWARFDie DWARFUnit::getParent(const DWARFDebugInfoEntry *Die) {
 | |
|   if (!Die)
 | |
|     return DWARFDie();
 | |
|   const uint32_t Depth = Die->getDepth();
 | |
|   // Unit DIEs always have a depth of zero and never have parents.
 | |
|   if (Depth == 0)
 | |
|     return DWARFDie();
 | |
|   // Depth of 1 always means parent is the compile/type unit.
 | |
|   if (Depth == 1)
 | |
|     return getUnitDIE();
 | |
|   // Look for previous DIE with a depth that is one less than the Die's depth.
 | |
|   const uint32_t ParentDepth = Depth - 1;
 | |
|   for (uint32_t I = getDIEIndex(Die) - 1; I > 0; --I) {
 | |
|     if (DieArray[I].getDepth() == ParentDepth)
 | |
|       return DWARFDie(this, &DieArray[I]);
 | |
|   }
 | |
|   return DWARFDie();
 | |
| }
 | |
| 
 | |
| DWARFDie DWARFUnit::getSibling(const DWARFDebugInfoEntry *Die) {
 | |
|   if (!Die)
 | |
|     return DWARFDie();
 | |
|   uint32_t Depth = Die->getDepth();
 | |
|   // Unit DIEs always have a depth of zero and never have siblings.
 | |
|   if (Depth == 0)
 | |
|     return DWARFDie();
 | |
|   // NULL DIEs don't have siblings.
 | |
|   if (Die->getAbbreviationDeclarationPtr() == nullptr)
 | |
|     return DWARFDie();
 | |
| 
 | |
|   // Find the next DIE whose depth is the same as the Die's depth.
 | |
|   for (size_t I = getDIEIndex(Die) + 1, EndIdx = DieArray.size(); I < EndIdx;
 | |
|        ++I) {
 | |
|     if (DieArray[I].getDepth() == Depth)
 | |
|       return DWARFDie(this, &DieArray[I]);
 | |
|   }
 | |
|   return DWARFDie();
 | |
| }
 | |
| 
 | |
| DWARFDie DWARFUnit::getPreviousSibling(const DWARFDebugInfoEntry *Die) {
 | |
|   if (!Die)
 | |
|     return DWARFDie();
 | |
|   uint32_t Depth = Die->getDepth();
 | |
|   // Unit DIEs always have a depth of zero and never have siblings.
 | |
|   if (Depth == 0)
 | |
|     return DWARFDie();
 | |
| 
 | |
|   // Find the previous DIE whose depth is the same as the Die's depth.
 | |
|   for (size_t I = getDIEIndex(Die); I > 0;) {
 | |
|     --I;
 | |
|     if (DieArray[I].getDepth() == Depth - 1)
 | |
|       return DWARFDie();
 | |
|     if (DieArray[I].getDepth() == Depth)
 | |
|       return DWARFDie(this, &DieArray[I]);
 | |
|   }
 | |
|   return DWARFDie();
 | |
| }
 | |
| 
 | |
| DWARFDie DWARFUnit::getFirstChild(const DWARFDebugInfoEntry *Die) {
 | |
|   if (!Die->hasChildren())
 | |
|     return DWARFDie();
 | |
| 
 | |
|   // We do not want access out of bounds when parsing corrupted debug data.
 | |
|   size_t I = getDIEIndex(Die) + 1;
 | |
|   if (I >= DieArray.size())
 | |
|     return DWARFDie();
 | |
|   return DWARFDie(this, &DieArray[I]);
 | |
| }
 | |
| 
 | |
| DWARFDie DWARFUnit::getLastChild(const DWARFDebugInfoEntry *Die) {
 | |
|   if (!Die->hasChildren())
 | |
|     return DWARFDie();
 | |
| 
 | |
|   uint32_t Depth = Die->getDepth();
 | |
|   for (size_t I = getDIEIndex(Die) + 1, EndIdx = DieArray.size(); I < EndIdx;
 | |
|        ++I) {
 | |
|     if (DieArray[I].getDepth() == Depth + 1 &&
 | |
|         DieArray[I].getTag() == dwarf::DW_TAG_null)
 | |
|       return DWARFDie(this, &DieArray[I]);
 | |
|     assert(DieArray[I].getDepth() > Depth && "Not processing children?");
 | |
|   }
 | |
|   return DWARFDie();
 | |
| }
 | |
| 
 | |
| const DWARFAbbreviationDeclarationSet *DWARFUnit::getAbbreviations() const {
 | |
|   if (!Abbrevs)
 | |
|     Abbrevs = Abbrev->getAbbreviationDeclarationSet(Header.getAbbrOffset());
 | |
|   return Abbrevs;
 | |
| }
 | |
| 
 | |
| llvm::Optional<object::SectionedAddress> DWARFUnit::getBaseAddress() {
 | |
|   if (BaseAddr)
 | |
|     return BaseAddr;
 | |
| 
 | |
|   DWARFDie UnitDie = getUnitDIE();
 | |
|   Optional<DWARFFormValue> PC = UnitDie.find({DW_AT_low_pc, DW_AT_entry_pc});
 | |
|   BaseAddr = toSectionedAddress(PC);
 | |
|   return BaseAddr;
 | |
| }
 | |
| 
 | |
| Expected<StrOffsetsContributionDescriptor>
 | |
| StrOffsetsContributionDescriptor::validateContributionSize(
 | |
|     DWARFDataExtractor &DA) {
 | |
|   uint8_t EntrySize = getDwarfOffsetByteSize();
 | |
|   // In order to ensure that we don't read a partial record at the end of
 | |
|   // the section we validate for a multiple of the entry size.
 | |
|   uint64_t ValidationSize = alignTo(Size, EntrySize);
 | |
|   // Guard against overflow.
 | |
|   if (ValidationSize >= Size)
 | |
|     if (DA.isValidOffsetForDataOfSize((uint32_t)Base, ValidationSize))
 | |
|       return *this;
 | |
|   return createStringError(errc::invalid_argument, "length exceeds section size");
 | |
| }
 | |
| 
 | |
| // Look for a DWARF64-formatted contribution to the string offsets table
 | |
| // starting at a given offset and record it in a descriptor.
 | |
| static Expected<StrOffsetsContributionDescriptor>
 | |
| parseDWARF64StringOffsetsTableHeader(DWARFDataExtractor &DA, uint64_t Offset) {
 | |
|   if (!DA.isValidOffsetForDataOfSize(Offset, 16))
 | |
|     return createStringError(errc::invalid_argument, "section offset exceeds section size");
 | |
| 
 | |
|   if (DA.getU32(&Offset) != dwarf::DW_LENGTH_DWARF64)
 | |
|     return createStringError(errc::invalid_argument, "32 bit contribution referenced from a 64 bit unit");
 | |
| 
 | |
|   uint64_t Size = DA.getU64(&Offset);
 | |
|   uint8_t Version = DA.getU16(&Offset);
 | |
|   (void)DA.getU16(&Offset); // padding
 | |
|   // The encoded length includes the 2-byte version field and the 2-byte
 | |
|   // padding, so we need to subtract them out when we populate the descriptor.
 | |
|   return StrOffsetsContributionDescriptor(Offset, Size - 4, Version, DWARF64);
 | |
| }
 | |
| 
 | |
| // Look for a DWARF32-formatted contribution to the string offsets table
 | |
| // starting at a given offset and record it in a descriptor.
 | |
| static Expected<StrOffsetsContributionDescriptor>
 | |
| parseDWARF32StringOffsetsTableHeader(DWARFDataExtractor &DA, uint64_t Offset) {
 | |
|   if (!DA.isValidOffsetForDataOfSize(Offset, 8))
 | |
|     return createStringError(errc::invalid_argument, "section offset exceeds section size");
 | |
| 
 | |
|   uint32_t ContributionSize = DA.getU32(&Offset);
 | |
|   if (ContributionSize >= dwarf::DW_LENGTH_lo_reserved)
 | |
|     return createStringError(errc::invalid_argument, "invalid length");
 | |
| 
 | |
|   uint8_t Version = DA.getU16(&Offset);
 | |
|   (void)DA.getU16(&Offset); // padding
 | |
|   // The encoded length includes the 2-byte version field and the 2-byte
 | |
|   // padding, so we need to subtract them out when we populate the descriptor.
 | |
|   return StrOffsetsContributionDescriptor(Offset, ContributionSize - 4, Version,
 | |
|                                           DWARF32);
 | |
| }
 | |
| 
 | |
| static Expected<StrOffsetsContributionDescriptor>
 | |
| parseDWARFStringOffsetsTableHeader(DWARFDataExtractor &DA,
 | |
|                                    llvm::dwarf::DwarfFormat Format,
 | |
|                                    uint64_t Offset) {
 | |
|   StrOffsetsContributionDescriptor Desc;
 | |
|   switch (Format) {
 | |
|   case dwarf::DwarfFormat::DWARF64: {
 | |
|     if (Offset < 16)
 | |
|       return createStringError(errc::invalid_argument, "insufficient space for 64 bit header prefix");
 | |
|     auto DescOrError = parseDWARF64StringOffsetsTableHeader(DA, Offset - 16);
 | |
|     if (!DescOrError)
 | |
|       return DescOrError.takeError();
 | |
|     Desc = *DescOrError;
 | |
|     break;
 | |
|   }
 | |
|   case dwarf::DwarfFormat::DWARF32: {
 | |
|     if (Offset < 8)
 | |
|       return createStringError(errc::invalid_argument, "insufficient space for 32 bit header prefix");
 | |
|     auto DescOrError = parseDWARF32StringOffsetsTableHeader(DA, Offset - 8);
 | |
|     if (!DescOrError)
 | |
|       return DescOrError.takeError();
 | |
|     Desc = *DescOrError;
 | |
|     break;
 | |
|   }
 | |
|   }
 | |
|   return Desc.validateContributionSize(DA);
 | |
| }
 | |
| 
 | |
| Expected<Optional<StrOffsetsContributionDescriptor>>
 | |
| DWARFUnit::determineStringOffsetsTableContribution(DWARFDataExtractor &DA) {
 | |
|   uint64_t Offset;
 | |
|   if (IsDWO) {
 | |
|     Offset = 0;
 | |
|     if (DA.getData().data() == nullptr)
 | |
|       return None;
 | |
|   } else {
 | |
|     auto OptOffset = toSectionOffset(getUnitDIE().find(DW_AT_str_offsets_base));
 | |
|     if (!OptOffset)
 | |
|       return None;
 | |
|     Offset = *OptOffset;
 | |
|   }
 | |
|   auto DescOrError = parseDWARFStringOffsetsTableHeader(DA, Header.getFormat(), Offset);
 | |
|   if (!DescOrError)
 | |
|     return DescOrError.takeError();
 | |
|   return *DescOrError;
 | |
| }
 | |
| 
 | |
| Expected<Optional<StrOffsetsContributionDescriptor>>
 | |
| DWARFUnit::determineStringOffsetsTableContributionDWO(DWARFDataExtractor & DA) {
 | |
|   uint64_t Offset = 0;
 | |
|   auto IndexEntry = Header.getIndexEntry();
 | |
|   const auto *C =
 | |
|       IndexEntry ? IndexEntry->getOffset(DW_SECT_STR_OFFSETS) : nullptr;
 | |
|   if (C)
 | |
|     Offset = C->Offset;
 | |
|   if (getVersion() >= 5) {
 | |
|     if (DA.getData().data() == nullptr)
 | |
|       return None;
 | |
|     Offset += Header.getFormat() == dwarf::DwarfFormat::DWARF32 ? 8 : 16;
 | |
|     // Look for a valid contribution at the given offset.
 | |
|     auto DescOrError = parseDWARFStringOffsetsTableHeader(DA, Header.getFormat(), Offset);
 | |
|     if (!DescOrError)
 | |
|       return DescOrError.takeError();
 | |
|     return *DescOrError;
 | |
|   }
 | |
|   // Prior to DWARF v5, we derive the contribution size from the
 | |
|   // index table (in a package file). In a .dwo file it is simply
 | |
|   // the length of the string offsets section.
 | |
|   if (!IndexEntry)
 | |
|     return {
 | |
|         Optional<StrOffsetsContributionDescriptor>(
 | |
|             {0, StringOffsetSection.Data.size(), 4, DWARF32})};
 | |
|   if (C)
 | |
|     return {Optional<StrOffsetsContributionDescriptor>(
 | |
|         {C->Offset, C->Length, 4, DWARF32})};
 | |
|   return None;
 | |
| }
 |