caio/clang-p2996
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
Files
a96480ebc187e4e3722b7cdfd582fe3441211b13
clang-p2996/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
Alexey Lapshin 77fc1f6049 [DebugInfo] add SectionedAddress to DebugInfo interfaces. 
That patch is the fix for https://bugs.llvm.org/show_bug.cgi?id=40703
   "wrong line number info for obj file compiled with -ffunction-sections"
   bug. The problem happened with only .o files. If object file contains
   several .text sections then line number information showed incorrectly.
   The reason for this is that DwarfLineTable could not detect section which
   corresponds to specified address(because address is the local to the
   section). And as the result it could not select proper sequence in the
   line table. The fix is to pass SectionIndex with the address. So that it
   would be possible to differentiate addresses from various sections. With
   this fix llvm-objdump shows correct line numbers for disassembled code.

   Differential review: https://reviews.llvm.org/D58194

llvm-svn: 354972
2019-02-27 13:17:36 +00:00

844 lines
31 KiB
C++
Raw Blame History

//===- DWARFUnit.cpp ------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "llvm/DebugInfo/DWARF/DWARFUnit.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/DebugInfo/DWARF/DWARFAbbreviationDeclaration.h"
#include "llvm/DebugInfo/DWARF/DWARFCompileUnit.h"
#include "llvm/DebugInfo/DWARF/DWARFContext.h"
#include "llvm/DebugInfo/DWARF/DWARFDebugAbbrev.h"
#include "llvm/DebugInfo/DWARF/DWARFDebugInfoEntry.h"
#include "llvm/DebugInfo/DWARF/DWARFDebugRnglists.h"
#include "llvm/DebugInfo/DWARF/DWARFDie.h"
#include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
#include "llvm/DebugInfo/DWARF/DWARFTypeUnit.h"
#include "llvm/Support/DataExtractor.h"
#include "llvm/Support/Errc.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/WithColor.h"
#include <algorithm>
#include <cassert>
#include <cstddef>
#include <cstdint>
#include <cstdio>
#include <utility>
#include <vector>
using namespace llvm;
using namespace dwarf;
void DWARFUnitVector::addUnitsForSection(DWARFContext &C,
const DWARFSection &Section,
DWARFSectionKind SectionKind) {
const DWARFObject &D = C.getDWARFObj();
addUnitsImpl(C, D, Section, C.getDebugAbbrev(), &D.getRangeSection(),
&D.getLocSection(), D.getStringSection(),
D.getStringOffsetSection(), &D.getAddrSection(),
D.getLineSection(), D.isLittleEndian(), false, false,
SectionKind);
}
void DWARFUnitVector::addUnitsForDWOSection(DWARFContext &C,
const DWARFSection &DWOSection,
DWARFSectionKind SectionKind,
bool Lazy) {
const DWARFObject &D = C.getDWARFObj();
addUnitsImpl(C, D, DWOSection, C.getDebugAbbrevDWO(), &D.getRangeDWOSection(),
&D.getLocDWOSection(), D.getStringDWOSection(),
D.getStringOffsetDWOSection(), &D.getAddrSection(),
D.getLineDWOSection(), C.isLittleEndian(), true, Lazy,
SectionKind);
}
void DWARFUnitVector::addUnitsImpl(
DWARFContext &Context, const DWARFObject &Obj, const DWARFSection &Section,
const DWARFDebugAbbrev *DA, const DWARFSection *RS,
const DWARFSection *LocSection, StringRef SS, const DWARFSection &SOS,
const DWARFSection *AOS, const DWARFSection &LS, bool LE, bool IsDWO,
bool Lazy, DWARFSectionKind SectionKind) {
DWARFDataExtractor Data(Obj, Section, LE, 0);
// Lazy initialization of Parser, now that we have all section info.
if (!Parser) {
Parser = [=, &Context, &Obj, &Section, &SOS,
&LS](uint32_t Offset, DWARFSectionKind SectionKind,
const DWARFSection *CurSection,
const DWARFUnitIndex::Entry *IndexEntry)
-> std::unique_ptr<DWARFUnit> {
const DWARFSection &InfoSection = CurSection ? *CurSection : Section;
DWARFDataExtractor Data(Obj, InfoSection, LE, 0);
if (!Data.isValidOffset(Offset))
return nullptr;
const DWARFUnitIndex *Index = nullptr;
if (IsDWO)
Index = &getDWARFUnitIndex(Context, SectionKind);
DWARFUnitHeader Header;
if (!Header.extract(Context, Data, &Offset, SectionKind, Index,
IndexEntry))
return nullptr;
std::unique_ptr<DWARFUnit> U;
if (Header.isTypeUnit())
U = llvm::make_unique<DWARFTypeUnit>(Context, InfoSection, Header, DA,
RS, LocSection, SS, SOS, AOS, LS,
LE, IsDWO, *this);
else
U = llvm::make_unique<DWARFCompileUnit>(Context, InfoSection, Header,
DA, RS, LocSection, SS, SOS,
AOS, LS, LE, IsDWO, *this);
return U;
};
}
if (Lazy)
return;
// Find a reasonable insertion point within the vector. We skip over
// (a) units from a different section, (b) units from the same section
// but with lower offset-within-section. This keeps units in order
// within a section, although not necessarily within the object file,
// even if we do lazy parsing.
auto I = this->begin();
uint32_t Offset = 0;
while (Data.isValidOffset(Offset)) {
if (I != this->end() &&
(&(*I)->getInfoSection() != &Section || (*I)->getOffset() == Offset)) {
++I;
continue;
}
auto U = Parser(Offset, SectionKind, &Section, nullptr);
// If parsing failed, we're done with this section.
if (!U)
break;
Offset = U->getNextUnitOffset();
I = std::next(this->insert(I, std::move(U)));
}
}
DWARFUnit *DWARFUnitVector::addUnit(std::unique_ptr<DWARFUnit> Unit) {
auto I = std::upper_bound(begin(), end(), Unit,
[](const std::unique_ptr<DWARFUnit> &LHS,
const std::unique_ptr<DWARFUnit> &RHS) {
return LHS->getOffset() < RHS->getOffset();
});
return this->insert(I, std::move(Unit))->get();
}
DWARFUnit *DWARFUnitVector::getUnitForOffset(uint32_t Offset) const {
auto end = begin() + getNumInfoUnits();
auto *CU =
std::upper_bound(begin(), end, Offset,
[](uint32_t LHS, const std::unique_ptr<DWARFUnit> &RHS) {
return LHS < RHS->getNextUnitOffset();
});
if (CU != end && (*CU)->getOffset() <= Offset)
return CU->get();
return nullptr;
}
DWARFUnit *
DWARFUnitVector::getUnitForIndexEntry(const DWARFUnitIndex::Entry &E) {
const auto *CUOff = E.getOffset(DW_SECT_INFO);
if (!CUOff)
return nullptr;
auto Offset = CUOff->Offset;
auto end = begin() + getNumInfoUnits();
auto *CU =
std::upper_bound(begin(), end, CUOff->Offset,
[](uint32_t LHS, const std::unique_ptr<DWARFUnit> &RHS) {
return LHS < RHS->getNextUnitOffset();
});
if (CU != end && (*CU)->getOffset() <= Offset)
return CU->get();
if (!Parser)
return nullptr;
auto U = Parser(Offset, DW_SECT_INFO, nullptr, &E);
if (!U)
U = nullptr;
auto *NewCU = U.get();
this->insert(CU, std::move(U));
++NumInfoUnits;
return NewCU;
}
DWARFUnit::DWARFUnit(DWARFContext &DC, const DWARFSection &Section,
const DWARFUnitHeader &Header, const DWARFDebugAbbrev *DA,
const DWARFSection *RS, const DWARFSection *LocSection,
StringRef SS, const DWARFSection &SOS,
const DWARFSection *AOS, const DWARFSection &LS, bool LE,
bool IsDWO, const DWARFUnitVector &UnitVector)
: Context(DC), InfoSection(Section), Header(Header), Abbrev(DA),
RangeSection(RS), LocSection(LocSection), LineSection(LS),
StringSection(SS), StringOffsetSection(SOS), AddrOffsetSection(AOS),
isLittleEndian(LE), IsDWO(IsDWO), UnitVector(UnitVector) {
clear();
// For split DWARF we only need to keep track of the location list section's
// data (no relocations), and if we are reading a package file, we need to
// adjust the location list data based on the index entries.
if (IsDWO) {
LocSectionData = LocSection->Data;
if (auto *IndexEntry = Header.getIndexEntry())
if (const auto *C = IndexEntry->getOffset(DW_SECT_LOC))
LocSectionData = LocSectionData.substr(C->Offset, C->Length);
}
}
DWARFUnit::~DWARFUnit() = default;
DWARFDataExtractor DWARFUnit::getDebugInfoExtractor() const {
return DWARFDataExtractor(Context.getDWARFObj(), InfoSection, isLittleEndian,
getAddressByteSize());
}
Optional<object::SectionedAddress>
DWARFUnit::getAddrOffsetSectionItem(uint32_t Index) const {
if (IsDWO) {
auto R = Context.info_section_units();
auto I = R.begin();
// Surprising if a DWO file has more than one skeleton unit in it - this
// probably shouldn't be valid, but if a use case is found, here's where to
// support it (probably have to linearly search for the matching skeleton CU
// here)
if (I != R.end() && std::next(I) == R.end())
return (*I)->getAddrOffsetSectionItem(Index);
}
uint32_t Offset = AddrOffsetSectionBase + Index * getAddressByteSize();
if (AddrOffsetSection->Data.size() < Offset + getAddressByteSize())
return None;
DWARFDataExtractor DA(Context.getDWARFObj(), *AddrOffsetSection,
isLittleEndian, getAddressByteSize());
uint64_t Section;
uint64_t Address = DA.getRelocatedAddress(&Offset, &Section);
return {{Address, Section}};
}
Optional<uint64_t> DWARFUnit::getStringOffsetSectionItem(uint32_t Index) const {
if (!StringOffsetsTableContribution)
return None;
unsigned ItemSize = getDwarfStringOffsetsByteSize();
uint32_t Offset = getStringOffsetsBase() + Index * ItemSize;
if (StringOffsetSection.Data.size() < Offset + ItemSize)
return None;
DWARFDataExtractor DA(Context.getDWARFObj(), StringOffsetSection,
isLittleEndian, 0);
return DA.getRelocatedValue(ItemSize, &Offset);
}
bool DWARFUnitHeader::extract(DWARFContext &Context,
const DWARFDataExtractor &debug_info,
uint32_t *offset_ptr,
DWARFSectionKind SectionKind,
const DWARFUnitIndex *Index,
const DWARFUnitIndex::Entry *Entry) {
Offset = *offset_ptr;
IndexEntry = Entry;
if (!IndexEntry && Index)
IndexEntry = Index->getFromOffset(*offset_ptr);
Length = debug_info.getU32(offset_ptr);
// FIXME: Support DWARF64.
unsigned SizeOfLength = 4;
FormParams.Format = DWARF32;
FormParams.Version = debug_info.getU16(offset_ptr);
if (FormParams.Version >= 5) {
UnitType = debug_info.getU8(offset_ptr);
FormParams.AddrSize = debug_info.getU8(offset_ptr);
AbbrOffset = debug_info.getU32(offset_ptr);
} else {
AbbrOffset = debug_info.getRelocatedValue(4, offset_ptr);
FormParams.AddrSize = debug_info.getU8(offset_ptr);
// Fake a unit type based on the section type. This isn't perfect,
// but distinguishing compile and type units is generally enough.
if (SectionKind == DW_SECT_TYPES)
UnitType = DW_UT_type;
else
UnitType = DW_UT_compile;
}
if (IndexEntry) {
if (AbbrOffset)
return false;
auto *UnitContrib = IndexEntry->getOffset();
if (!UnitContrib || UnitContrib->Length != (Length + 4))
return false;
auto *AbbrEntry = IndexEntry->getOffset(DW_SECT_ABBREV);
if (!AbbrEntry)
return false;
AbbrOffset = AbbrEntry->Offset;
}
if (isTypeUnit()) {
TypeHash = debug_info.getU64(offset_ptr);
TypeOffset = debug_info.getU32(offset_ptr);
} else if (UnitType == DW_UT_split_compile || UnitType == DW_UT_skeleton)
DWOId = debug_info.getU64(offset_ptr);
// Header fields all parsed, capture the size of this unit header.
assert(*offset_ptr - Offset <= 255 && "unexpected header size");
Size = uint8_t(*offset_ptr - Offset);
// Type offset is unit-relative; should be after the header and before
// the end of the current unit.
bool TypeOffsetOK =
!isTypeUnit()
? true
: TypeOffset >= Size && TypeOffset < getLength() + SizeOfLength;
bool LengthOK = debug_info.isValidOffset(getNextUnitOffset() - 1);
bool VersionOK = DWARFContext::isSupportedVersion(getVersion());
bool AddrSizeOK = getAddressByteSize() == 4 || getAddressByteSize() == 8;
if (!LengthOK || !VersionOK || !AddrSizeOK || !TypeOffsetOK)
return false;
// Keep track of the highest DWARF version we encounter across all units.
Context.setMaxVersionIfGreater(getVersion());
return true;
}
// Parse the rangelist table header, including the optional array of offsets
// following it (DWARF v5 and later).
static Expected<DWARFDebugRnglistTable>
parseRngListTableHeader(DWARFDataExtractor &DA, uint32_t Offset) {
// TODO: Support DWARF64
// We are expected to be called with Offset 0 or pointing just past the table
// header, which is 12 bytes long for DWARF32.
if (Offset > 0) {
if (Offset < 12U)
return createStringError(errc::invalid_argument, "Did not detect a valid"
" range list table with base = 0x%" PRIu32,
Offset);
Offset -= 12U;
}
llvm::DWARFDebugRnglistTable Table;
if (Error E = Table.extractHeaderAndOffsets(DA, &Offset))
return std::move(E);
return Table;
}
Error DWARFUnit::extractRangeList(uint32_t RangeListOffset,
DWARFDebugRangeList &RangeList) const {
// Require that compile unit is extracted.
assert(!DieArray.empty());
DWARFDataExtractor RangesData(Context.getDWARFObj(), *RangeSection,
isLittleEndian, getAddressByteSize());
uint32_t ActualRangeListOffset = RangeSectionBase + RangeListOffset;
return RangeList.extract(RangesData, &ActualRangeListOffset);
}
void DWARFUnit::clear() {
Abbrevs = nullptr;
BaseAddr.reset();
RangeSectionBase = 0;
AddrOffsetSectionBase = 0;
clearDIEs(false);
DWO.reset();
}
const char *DWARFUnit::getCompilationDir() {
return dwarf::toString(getUnitDIE().find(DW_AT_comp_dir), nullptr);
}
void DWARFUnit::extractDIEsToVector(
bool AppendCUDie, bool AppendNonCUDies,
std::vector<DWARFDebugInfoEntry> &Dies) const {
if (!AppendCUDie && !AppendNonCUDies)
return;
// Set the offset to that of the first DIE and calculate the start of the
// next compilation unit header.
uint32_t DIEOffset = getOffset() + getHeaderSize();
uint32_t NextCUOffset = getNextUnitOffset();
DWARFDebugInfoEntry DIE;
DWARFDataExtractor DebugInfoData = getDebugInfoExtractor();
uint32_t Depth = 0;
bool IsCUDie = true;
while (DIE.extractFast(*this, &DIEOffset, DebugInfoData, NextCUOffset,
Depth)) {
if (IsCUDie) {
if (AppendCUDie)
Dies.push_back(DIE);
if (!AppendNonCUDies)
break;
// The average bytes per DIE entry has been seen to be
// around 14-20 so let's pre-reserve the needed memory for
// our DIE entries accordingly.
Dies.reserve(Dies.size() + getDebugInfoSize() / 14);
IsCUDie = false;
} else {
Dies.push_back(DIE);
}
if (const DWARFAbbreviationDeclaration *AbbrDecl =
DIE.getAbbreviationDeclarationPtr()) {
// Normal DIE
if (AbbrDecl->hasChildren())
++Depth;
} else {
// NULL DIE.
if (Depth > 0)
--Depth;
if (Depth == 0)
break; // We are done with this compile unit!
}
}
// Give a little bit of info if we encounter corrupt DWARF (our offset
// should always terminate at or before the start of the next compilation
// unit header).
if (DIEOffset > NextCUOffset)
WithColor::warning() << format("DWARF compile unit extends beyond its "
"bounds cu 0x%8.8x at 0x%8.8x\n",
getOffset(), DIEOffset);
}
size_t DWARFUnit::extractDIEsIfNeeded(bool CUDieOnly) {
if ((CUDieOnly && !DieArray.empty()) ||
DieArray.size() > 1)
return 0; // Already parsed.
bool HasCUDie = !DieArray.empty();
extractDIEsToVector(!HasCUDie, !CUDieOnly, DieArray);
if (DieArray.empty())
return 0;
// If CU DIE was just parsed, copy several attribute values from it.
if (!HasCUDie) {
DWARFDie UnitDie = getUnitDIE();
if (Optional<uint64_t> DWOId = toUnsigned(UnitDie.find(DW_AT_GNU_dwo_id)))
Header.setDWOId(*DWOId);
if (!IsDWO) {
assert(AddrOffsetSectionBase == 0);
assert(RangeSectionBase == 0);
AddrOffsetSectionBase = toSectionOffset(UnitDie.find(DW_AT_addr_base), 0);
if (!AddrOffsetSectionBase)
AddrOffsetSectionBase =
toSectionOffset(UnitDie.find(DW_AT_GNU_addr_base), 0);
RangeSectionBase = toSectionOffset(UnitDie.find(DW_AT_rnglists_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)
StringOffsetsTableContribution =
determineStringOffsetsTableContributionDWO(DA);
else if (getVersion() >= 5)
StringOffsetsTableContribution =
determineStringOffsetsTableContribution(DA);
// 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);
if (auto TableOrError =
parseRngListTableHeader(RangesDA, RangeSectionBase))
RngListTable = TableOrError.get();
else
WithColor::error() << "parsing a range list table: "
<< toString(TableOrError.takeError())
<< '\n';
// 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();
}
}
// 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 DieArray.size();
}
bool DWARFUnit::parseDWO() {
if (IsDWO)
return false;
if (DWO.get())
return false;
DWARFDie UnitDie = getUnitDIE();
if (!UnitDie)
return false;
auto DWOFileName = 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
DWO->setAddrOffsetSection(AddrOffsetSection, AddrOffsetSectionBase);
if (getVersion() >= 5) {
DWO->setRangesSection(&Context.getDWARFObj().getRnglistsDWOSection(), 0);
DWARFDataExtractor RangesDA(Context.getDWARFObj(), *RangeSection,
isLittleEndian, 0);
if (auto TableOrError = parseRngListTableHeader(RangesDA, RangeSectionBase))
DWO->RngListTable = TableOrError.get();
else
WithColor::error() << "parsing a range list table: "
<< toString(TableOrError.takeError())
<< '\n';
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(uint32_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 + RangeSectionBase);
if (RngListTable)
return createStringError(errc::invalid_argument,
"invalid range list table index %d", Index);
else
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;
}
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.get() : 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;
}
Optional<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 None;
}
// Look for a DWARF64-formatted contribution to the string offsets table
// starting at a given offset and record it in a descriptor.
static Optional<StrOffsetsContributionDescriptor>
parseDWARF64StringOffsetsTableHeader(DWARFDataExtractor &DA, uint32_t Offset) {
if (!DA.isValidOffsetForDataOfSize(Offset, 16))
return None;
if (DA.getU32(&Offset) != 0xffffffff)
return None;
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 {{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 Optional<StrOffsetsContributionDescriptor>
parseDWARF32StringOffsetsTableHeader(DWARFDataExtractor &DA, uint32_t Offset) {
if (!DA.isValidOffsetForDataOfSize(Offset, 8))
return None;
uint32_t ContributionSize = DA.getU32(&Offset);
if (ContributionSize >= 0xfffffff0)
return None;
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 {{Offset, ContributionSize - 4, Version, DWARF32}};
}
Optional<StrOffsetsContributionDescriptor>
DWARFUnit::determineStringOffsetsTableContribution(DWARFDataExtractor &DA) {
auto Offset = toSectionOffset(getUnitDIE().find(DW_AT_str_offsets_base), 0);
Optional<StrOffsetsContributionDescriptor> Descriptor;
// Attempt to find a DWARF64 contribution 16 bytes before the base.
if (Offset >= 16)
Descriptor =
parseDWARF64StringOffsetsTableHeader(DA, (uint32_t)Offset - 16);
// Try to find a DWARF32 contribution 8 bytes before the base.
if (!Descriptor && Offset >= 8)
Descriptor = parseDWARF32StringOffsetsTableHeader(DA, (uint32_t)Offset - 8);
return Descriptor ? Descriptor->validateContributionSize(DA) : Descriptor;
}
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) {
// Look for a valid contribution at the given offset.
auto Descriptor =
parseDWARF64StringOffsetsTableHeader(DA, (uint32_t)Offset);
if (!Descriptor)
Descriptor = parseDWARF32StringOffsetsTableHeader(DA, (uint32_t)Offset);
return Descriptor ? Descriptor->validateContributionSize(DA) : Descriptor;
}
// 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 {{0, StringOffsetSection.Data.size(), 4, DWARF32}};
if (C)
return {{C->Offset, C->Length, 4, DWARF32}};
return None;
}
Reference in New Issue View Git Blame Copy Permalink