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llvm-project/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp

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//===- DWARFContext.cpp ---------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/DebugInfo/DWARF/DWARFContext.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h"
#include "llvm/DebugInfo/DWARF/DWARFCompileUnit.h"
#include "llvm/DebugInfo/DWARF/DWARFDebugAbbrev.h"
#include "llvm/DebugInfo/DWARF/DWARFDebugArangeSet.h"
#include "llvm/DebugInfo/DWARF/DWARFDebugAranges.h"
#include "llvm/DebugInfo/DWARF/DWARFDebugFrame.h"
#include "llvm/DebugInfo/DWARF/DWARFDebugLine.h"
#include "llvm/DebugInfo/DWARF/DWARFDebugLoc.h"
#include "llvm/DebugInfo/DWARF/DWARFDebugMacro.h"
#include "llvm/DebugInfo/DWARF/DWARFDebugPubTable.h"
#include "llvm/DebugInfo/DWARF/DWARFDebugRangeList.h"
#include "llvm/DebugInfo/DWARF/DWARFDie.h"
#include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
#include "llvm/DebugInfo/DWARF/DWARFGdbIndex.h"
#include "llvm/DebugInfo/DWARF/DWARFSection.h"
#include "llvm/DebugInfo/DWARF/DWARFUnitIndex.h"
#include "llvm/DebugInfo/DWARF/DWARFVerifier.h"
#include "llvm/Object/Decompressor.h"
#include "llvm/Object/MachO.h"
#include "llvm/Object/ObjectFile.h"
#include "llvm/Object/RelocVisitor.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/DataExtractor.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
#include <cstdint>
#include <map>
#include <set>
#include <string>
#include <utility>
#include <vector>
using namespace llvm;
using namespace dwarf;
using namespace object;
#define DEBUG_TYPE "dwarf"
typedef DWARFDebugLine::LineTable DWARFLineTable;
typedef DILineInfoSpecifier::FileLineInfoKind FileLineInfoKind;
typedef DILineInfoSpecifier::FunctionNameKind FunctionNameKind;
uint64_t llvm::getRelocatedValue(const DataExtractor &Data, uint32_t Size,
uint32_t *Off, const RelocAddrMap *Relocs,
uint64_t *SectionIndex) {
if (!Relocs)
return Data.getUnsigned(Off, Size);
RelocAddrMap::const_iterator AI = Relocs->find(*Off);
if (AI == Relocs->end())
return Data.getUnsigned(Off, Size);
if (SectionIndex)
*SectionIndex = AI->second.SectionIndex;
return Data.getUnsigned(Off, Size) + AI->second.Value;
}
static void dumpAccelSection(raw_ostream &OS, StringRef Name,
const DWARFSection& Section, StringRef StringSection,
bool LittleEndian) {
DataExtractor AccelSection(Section.Data, LittleEndian, 0);
DataExtractor StrData(StringSection, LittleEndian, 0);
OS << "\n." << Name << " contents:\n";
DWARFAcceleratorTable Accel(AccelSection, StrData, Section.Relocs);
if (!Accel.extract())
return;
Accel.dump(OS);
}
void DWARFContext::dump(raw_ostream &OS, DIDumpType DumpType, bool DumpEH,
bool SummarizeTypes) {
if (DumpType == DIDT_All || DumpType == DIDT_Abbrev) {
OS << ".debug_abbrev contents:\n";
getDebugAbbrev()->dump(OS);
}
if (DumpType == DIDT_All || DumpType == DIDT_AbbrevDwo)
if (const DWARFDebugAbbrev *D = getDebugAbbrevDWO()) {
OS << "\n.debug_abbrev.dwo contents:\n";
D->dump(OS);
}
if (DumpType == DIDT_All || DumpType == DIDT_Info) {
OS << "\n.debug_info contents:\n";
for (const auto &CU : compile_units())
CU->dump(OS);
}
if ((DumpType == DIDT_All || DumpType == DIDT_InfoDwo) &&
getNumDWOCompileUnits()) {
OS << "\n.debug_info.dwo contents:\n";
for (const auto &DWOCU : dwo_compile_units())
DWOCU->dump(OS);
}
if ((DumpType == DIDT_All || DumpType == DIDT_Types) && getNumTypeUnits()) {
OS << "\n.debug_types contents:\n";
for (const auto &TUS : type_unit_sections())
for (const auto &TU : TUS)
TU->dump(OS, SummarizeTypes);
}
if ((DumpType == DIDT_All || DumpType == DIDT_TypesDwo) &&
getNumDWOTypeUnits()) {
OS << "\n.debug_types.dwo contents:\n";
for (const auto &DWOTUS : dwo_type_unit_sections())
for (const auto &DWOTU : DWOTUS)
DWOTU->dump(OS, SummarizeTypes);
}
if (DumpType == DIDT_All || DumpType == DIDT_Loc) {
OS << "\n.debug_loc contents:\n";
getDebugLoc()->dump(OS);
}
if (DumpType == DIDT_All || DumpType == DIDT_LocDwo) {
OS << "\n.debug_loc.dwo contents:\n";
getDebugLocDWO()->dump(OS);
}
if (DumpType == DIDT_All || DumpType == DIDT_Frames) {
OS << "\n.debug_frame contents:\n";
getDebugFrame()->dump(OS);
if (DumpEH) {
OS << "\n.eh_frame contents:\n";
getEHFrame()->dump(OS);
}
}
if (DumpType == DIDT_All || DumpType == DIDT_Macro) {
OS << "\n.debug_macinfo contents:\n";
getDebugMacro()->dump(OS);
}
uint32_t offset = 0;
if (DumpType == DIDT_All || DumpType == DIDT_Aranges) {
OS << "\n.debug_aranges contents:\n";
DataExtractor arangesData(getARangeSection(), isLittleEndian(), 0);
DWARFDebugArangeSet set;
while (set.extract(arangesData, &offset))
set.dump(OS);
}
uint8_t savedAddressByteSize = 0;
if (DumpType == DIDT_All || DumpType == DIDT_Line) {
OS << "\n.debug_line contents:\n";
for (const auto &CU : compile_units()) {
savedAddressByteSize = CU->getAddressByteSize();
auto CUDIE = CU->getUnitDIE();
if (!CUDIE)
continue;
if (auto StmtOffset = toSectionOffset(CUDIE.find(DW_AT_stmt_list))) {
DataExtractor lineData(getLineSection().Data, isLittleEndian(),
savedAddressByteSize);
DWARFDebugLine::LineTable LineTable;
uint32_t Offset = *StmtOffset;
LineTable.parse(lineData, &getLineSection().Relocs, &Offset);
LineTable.dump(OS);
}
}
}
if (DumpType == DIDT_All || DumpType == DIDT_CUIndex) {
OS << "\n.debug_cu_index contents:\n";
getCUIndex().dump(OS);
}
if (DumpType == DIDT_All || DumpType == DIDT_TUIndex) {
OS << "\n.debug_tu_index contents:\n";
getTUIndex().dump(OS);
}
if (DumpType == DIDT_All || DumpType == DIDT_LineDwo) {
OS << "\n.debug_line.dwo contents:\n";
unsigned stmtOffset = 0;
DataExtractor lineData(getLineDWOSection().Data, isLittleEndian(),
savedAddressByteSize);
DWARFDebugLine::LineTable LineTable;
while (LineTable.Prologue.parse(lineData, &stmtOffset)) {
LineTable.dump(OS);
LineTable.clear();
}
}
if (DumpType == DIDT_All || DumpType == DIDT_Str) {
OS << "\n.debug_str contents:\n";
DataExtractor strData(getStringSection(), isLittleEndian(), 0);
offset = 0;
uint32_t strOffset = 0;
while (const char *s = strData.getCStr(&offset)) {
OS << format("0x%8.8x: \"%s\"\n", strOffset, s);
strOffset = offset;
}
}
if ((DumpType == DIDT_All || DumpType == DIDT_StrDwo) &&
!getStringDWOSection().empty()) {
OS << "\n.debug_str.dwo contents:\n";
DataExtractor strDWOData(getStringDWOSection(), isLittleEndian(), 0);
offset = 0;
uint32_t strDWOOffset = 0;
while (const char *s = strDWOData.getCStr(&offset)) {
OS << format("0x%8.8x: \"%s\"\n", strDWOOffset, s);
strDWOOffset = offset;
}
}
if (DumpType == DIDT_All || DumpType == DIDT_Ranges) {
OS << "\n.debug_ranges contents:\n";
// In fact, different compile units may have different address byte
// sizes, but for simplicity we just use the address byte size of the last
// compile unit (there is no easy and fast way to associate address range
// list and the compile unit it describes).
DataExtractor rangesData(getRangeSection().Data, isLittleEndian(),
savedAddressByteSize);
offset = 0;
DWARFDebugRangeList rangeList;
while (rangeList.extract(rangesData, &offset, getRangeSection().Relocs))
rangeList.dump(OS);
}
if (DumpType == DIDT_All || DumpType == DIDT_Pubnames)
DWARFDebugPubTable(getPubNamesSection(), isLittleEndian(), false)
.dump("debug_pubnames", OS);
if (DumpType == DIDT_All || DumpType == DIDT_Pubtypes)
DWARFDebugPubTable(getPubTypesSection(), isLittleEndian(), false)
.dump("debug_pubtypes", OS);
if (DumpType == DIDT_All || DumpType == DIDT_GnuPubnames)
DWARFDebugPubTable(getGnuPubNamesSection(), isLittleEndian(),
true /* GnuStyle */)
.dump("debug_gnu_pubnames", OS);
if (DumpType == DIDT_All || DumpType == DIDT_GnuPubtypes)
DWARFDebugPubTable(getGnuPubTypesSection(), isLittleEndian(),
true /* GnuStyle */)
.dump("debug_gnu_pubtypes", OS);
if ((DumpType == DIDT_All || DumpType == DIDT_StrOffsetsDwo) &&
!getStringOffsetDWOSection().empty()) {
OS << "\n.debug_str_offsets.dwo contents:\n";
DataExtractor strOffsetExt(getStringOffsetDWOSection(), isLittleEndian(),
0);
offset = 0;
uint64_t size = getStringOffsetDWOSection().size();
while (offset < size) {
OS << format("0x%8.8x: ", offset);
OS << format("%8.8x\n", strOffsetExt.getU32(&offset));
}
}
if ((DumpType == DIDT_All || DumpType == DIDT_GdbIndex) &&
!getGdbIndexSection().empty()) {
OS << "\n.gnu_index contents:\n";
getGdbIndex().dump(OS);
}
if (DumpType == DIDT_All || DumpType == DIDT_AppleNames)
dumpAccelSection(OS, "apple_names", getAppleNamesSection(),
getStringSection(), isLittleEndian());
if (DumpType == DIDT_All || DumpType == DIDT_AppleTypes)
dumpAccelSection(OS, "apple_types", getAppleTypesSection(),
getStringSection(), isLittleEndian());
if (DumpType == DIDT_All || DumpType == DIDT_AppleNamespaces)
dumpAccelSection(OS, "apple_namespaces", getAppleNamespacesSection(),
getStringSection(), isLittleEndian());
if (DumpType == DIDT_All || DumpType == DIDT_AppleObjC)
dumpAccelSection(OS, "apple_objc", getAppleObjCSection(),
getStringSection(), isLittleEndian());
}
DWARFCompileUnit *DWARFContext::getDWOCompileUnitForHash(uint64_t Hash) {
// FIXME: Improve this for the case where this DWO file is really a DWP file
// with an index - use the index for lookup instead of a linear search.
for (const auto &DWOCU : dwo_compile_units())
if (DWOCU->getDWOId() == Hash)
return DWOCU.get();
return nullptr;
}
DWARFDie DWARFContext::getDIEForOffset(uint32_t Offset) {
parseCompileUnits();
if (auto *CU = CUs.getUnitForOffset(Offset))
return CU->getDIEForOffset(Offset);
return DWARFDie();
}
namespace {
class Verifier {
raw_ostream &OS;
DWARFContext &DCtx;
public:
Verifier(raw_ostream &S, DWARFContext &D) : OS(S), DCtx(D) {}
bool HandleDebugInfo() {
bool Success = true;
// A map that tracks all references (converted absolute references) so we
// can verify each reference points to a valid DIE and not an offset that
// lies between to valid DIEs.
std::map<uint64_t, std::set<uint32_t>> ReferenceToDIEOffsets;
OS << "Verifying .debug_info...\n";
for (const auto &CU : DCtx.compile_units()) {
unsigned NumDies = CU->getNumDIEs();
for (unsigned I = 0; I < NumDies; ++I) {
auto Die = CU->getDIEAtIndex(I);
const auto Tag = Die.getTag();
if (Tag == DW_TAG_null)
continue;
for (auto AttrValue : Die.attributes()) {
const auto Attr = AttrValue.Attr;
const auto Form = AttrValue.Value.getForm();
switch (Attr) {
case DW_AT_ranges:
// Make sure the offset in the DW_AT_ranges attribute is valid.
if (auto SectionOffset = AttrValue.Value.getAsSectionOffset()) {
if (*SectionOffset >= DCtx.getRangeSection().Data.size()) {
Success = false;
OS << "error: DW_AT_ranges offset is beyond .debug_ranges "
"bounds:\n";
Die.dump(OS, 0);
OS << "\n";
}
} else {
Success = false;
OS << "error: DIE has invalid DW_AT_ranges encoding:\n";
Die.dump(OS, 0);
OS << "\n";
}
break;
case DW_AT_stmt_list:
// Make sure the offset in the DW_AT_stmt_list attribute is valid.
if (auto SectionOffset = AttrValue.Value.getAsSectionOffset()) {
if (*SectionOffset >= DCtx.getLineSection().Data.size()) {
Success = false;
OS << "error: DW_AT_stmt_list offset is beyond .debug_line "
"bounds: "
<< format("0x%08" PRIx32, *SectionOffset) << "\n";
CU->getUnitDIE().dump(OS, 0);
OS << "\n";
}
} else {
Success = false;
OS << "error: DIE has invalid DW_AT_stmt_list encoding:\n";
Die.dump(OS, 0);
OS << "\n";
}
break;
default:
break;
}
switch (Form) {
case DW_FORM_ref1:
case DW_FORM_ref2:
case DW_FORM_ref4:
case DW_FORM_ref8:
case DW_FORM_ref_udata: {
// Verify all CU relative references are valid CU offsets.
Optional<uint64_t> RefVal = AttrValue.Value.getAsReference();
assert(RefVal);
if (RefVal) {
auto DieCU = Die.getDwarfUnit();
auto CUSize = DieCU->getNextUnitOffset() - DieCU->getOffset();
auto CUOffset = AttrValue.Value.getRawUValue();
if (CUOffset >= CUSize) {
Success = false;
OS << "error: " << FormEncodingString(Form) << " CU offset "
<< format("0x%08" PRIx32, CUOffset)
<< " is invalid (must be less than CU size of "
<< format("0x%08" PRIx32, CUSize) << "):\n";
Die.dump(OS, 0);
OS << "\n";
} else {
// Valid reference, but we will verify it points to an actual
// DIE later.
ReferenceToDIEOffsets[*RefVal].insert(Die.getOffset());
}
}
break;
}
case DW_FORM_ref_addr: {
// Verify all absolute DIE references have valid offsets in the
// .debug_info section.
Optional<uint64_t> RefVal = AttrValue.Value.getAsReference();
assert(RefVal);
if (RefVal) {
if(*RefVal >= DCtx.getInfoSection().Data.size()) {
Success = false;
OS << "error: DW_FORM_ref_addr offset beyond .debug_info "
"bounds:\n";
Die.dump(OS, 0);
OS << "\n";
} else {
// Valid reference, but we will verify it points to an actual
// DIE later.
ReferenceToDIEOffsets[*RefVal].insert(Die.getOffset());
}
}
break;
}
case DW_FORM_strp: {
auto SecOffset = AttrValue.Value.getAsSectionOffset();
assert(SecOffset); // DW_FORM_strp is a section offset.
if (SecOffset && *SecOffset >= DCtx.getStringSection().size()) {
Success = false;
OS << "error: DW_FORM_strp offset beyond .debug_str bounds:\n";
Die.dump(OS, 0);
OS << "\n";
}
break;
}
default:
break;
}
}
}
}
// Take all references and make sure they point to an actual DIE by
// getting the DIE by offset and emitting an error
OS << "Verifying .debug_info references...\n";
for (auto Pair: ReferenceToDIEOffsets) {
auto Die = DCtx.getDIEForOffset(Pair.first);
if (Die)
continue;
Success = false;
OS << "error: invalid DIE reference " << format("0x%08" PRIx64, Pair.first)
<< ". Offset is in between DIEs:\n";
for (auto Offset: Pair.second) {
auto ReferencingDie = DCtx.getDIEForOffset(Offset);
ReferencingDie.dump(OS, 0);
OS << "\n";
}
OS << "\n";
}
return Success;
}
bool HandleDebugLine() {
std::map<uint64_t, DWARFDie> StmtListToDie;
bool Success = true;
OS << "Verifying .debug_line...\n";
for (const auto &CU : DCtx.compile_units()) {
uint32_t LineTableOffset = 0;
auto CUDie = CU->getUnitDIE();
auto StmtFormValue = CUDie.find(DW_AT_stmt_list);
if (!StmtFormValue) {
// No line table for this compile unit.
continue;
}
// Get the attribute value as a section offset. No need to produce an
// error here if the encoding isn't correct because we validate this in
// the .debug_info verifier.
if (auto StmtSectionOffset = toSectionOffset(StmtFormValue)) {
LineTableOffset = *StmtSectionOffset;
if (LineTableOffset >= DCtx.getLineSection().Data.size()) {
// Make sure we don't get a valid line table back if the offset
// is wrong.
assert(DCtx.getLineTableForUnit(CU.get()) == nullptr);
// Skip this line table as it isn't valid. No need to create an error
// here because we validate this in the .debug_info verifier.
continue;
} else {
auto Iter = StmtListToDie.find(LineTableOffset);
if (Iter != StmtListToDie.end()) {
Success = false;
OS << "error: two compile unit DIEs, "
<< format("0x%08" PRIx32, Iter->second.getOffset()) << " and "
<< format("0x%08" PRIx32, CUDie.getOffset())
<< ", have the same DW_AT_stmt_list section offset:\n";
Iter->second.dump(OS, 0);
CUDie.dump(OS, 0);
OS << '\n';
// Already verified this line table before, no need to do it again.
continue;
}
StmtListToDie[LineTableOffset] = CUDie;
}
}
auto LineTable = DCtx.getLineTableForUnit(CU.get());
if (!LineTable) {
Success = false;
OS << "error: .debug_line[" << format("0x%08" PRIx32, LineTableOffset)
<< "] was not able to be parsed for CU:\n";
CUDie.dump(OS, 0);
OS << '\n';
continue;
}
uint32_t MaxFileIndex = LineTable->Prologue.FileNames.size();
uint64_t PrevAddress = 0;
uint32_t RowIndex = 0;
for (const auto &Row : LineTable->Rows) {
if (Row.Address < PrevAddress) {
Success = false;
OS << "error: .debug_line[" << format("0x%08" PRIx32, LineTableOffset)
<< "] row[" << RowIndex
<< "] decreases in address from previous row:\n";
DWARFDebugLine::Row::dumpTableHeader(OS);
if (RowIndex > 0)
LineTable->Rows[RowIndex - 1].dump(OS);
Row.dump(OS);
OS << '\n';
}
if (Row.File > MaxFileIndex) {
Success = false;
OS << "error: .debug_line[" << format("0x%08" PRIx32, LineTableOffset)
<< "][" << RowIndex << "] has invalid file index " << Row.File
<< " (valid values are [1," << MaxFileIndex << "]):\n";
DWARFDebugLine::Row::dumpTableHeader(OS);
Row.dump(OS);
OS << '\n';
}
if (Row.EndSequence)
PrevAddress = 0;
else
PrevAddress = Row.Address;
++RowIndex;
}
}
return Success;
}
};
} // anonymous namespace
bool DWARFContext::verify(raw_ostream &OS, DIDumpType DumpType) {
bool Success = true;
DWARFVerifier verifier(OS, *this);
if (DumpType == DIDT_All || DumpType == DIDT_Info) {
if (!verifier.handleDebugInfo())
Success = false;
}
if (DumpType == DIDT_All || DumpType == DIDT_Line) {
if (!verifier.handleDebugLine())
Success = false;
}
return Success;
}
const DWARFUnitIndex &DWARFContext::getCUIndex() {
if (CUIndex)
return *CUIndex;
DataExtractor CUIndexData(getCUIndexSection(), isLittleEndian(), 0);
CUIndex = llvm::make_unique<DWARFUnitIndex>(DW_SECT_INFO);
CUIndex->parse(CUIndexData);
return *CUIndex;
}
const DWARFUnitIndex &DWARFContext::getTUIndex() {
if (TUIndex)
return *TUIndex;
DataExtractor TUIndexData(getTUIndexSection(), isLittleEndian(), 0);
TUIndex = llvm::make_unique<DWARFUnitIndex>(DW_SECT_TYPES);
TUIndex->parse(TUIndexData);
return *TUIndex;
}
DWARFGdbIndex &DWARFContext::getGdbIndex() {
if (GdbIndex)
return *GdbIndex;
DataExtractor GdbIndexData(getGdbIndexSection(), true /*LE*/, 0);
GdbIndex = llvm::make_unique<DWARFGdbIndex>();
GdbIndex->parse(GdbIndexData);
return *GdbIndex;
}
const DWARFDebugAbbrev *DWARFContext::getDebugAbbrev() {
if (Abbrev)
return Abbrev.get();
DataExtractor abbrData(getAbbrevSection(), isLittleEndian(), 0);
Abbrev.reset(new DWARFDebugAbbrev());
Abbrev->extract(abbrData);
return Abbrev.get();
}
const DWARFDebugAbbrev *DWARFContext::getDebugAbbrevDWO() {
if (AbbrevDWO)
return AbbrevDWO.get();
DataExtractor abbrData(getAbbrevDWOSection(), isLittleEndian(), 0);
AbbrevDWO.reset(new DWARFDebugAbbrev());
AbbrevDWO->extract(abbrData);
return AbbrevDWO.get();
}
const DWARFDebugLoc *DWARFContext::getDebugLoc() {
if (Loc)
return Loc.get();
DataExtractor LocData(getLocSection().Data, isLittleEndian(), 0);
Loc.reset(new DWARFDebugLoc(getLocSection().Relocs));
// assume all compile units have the same address byte size
if (getNumCompileUnits())
Loc->parse(LocData, getCompileUnitAtIndex(0)->getAddressByteSize());
return Loc.get();
}
const DWARFDebugLocDWO *DWARFContext::getDebugLocDWO() {
if (LocDWO)
return LocDWO.get();
DataExtractor LocData(getLocDWOSection().Data, isLittleEndian(), 0);
LocDWO.reset(new DWARFDebugLocDWO());
LocDWO->parse(LocData);
return LocDWO.get();
}
const DWARFDebugAranges *DWARFContext::getDebugAranges() {
if (Aranges)
return Aranges.get();
Aranges.reset(new DWARFDebugAranges());
Aranges->generate(this);
return Aranges.get();
}
const DWARFDebugFrame *DWARFContext::getDebugFrame() {
if (DebugFrame)
return DebugFrame.get();
// There's a "bug" in the DWARFv3 standard with respect to the target address
// size within debug frame sections. While DWARF is supposed to be independent
// of its container, FDEs have fields with size being "target address size",
// which isn't specified in DWARF in general. It's only specified for CUs, but
// .eh_frame can appear without a .debug_info section. Follow the example of
// other tools (libdwarf) and extract this from the container (ObjectFile
// provides this information). This problem is fixed in DWARFv4
// See this dwarf-discuss discussion for more details:
// http://lists.dwarfstd.org/htdig.cgi/dwarf-discuss-dwarfstd.org/2011-December/001173.html
DataExtractor debugFrameData(getDebugFrameSection(), isLittleEndian(),
getAddressSize());
DebugFrame.reset(new DWARFDebugFrame(false /* IsEH */));
DebugFrame->parse(debugFrameData);
return DebugFrame.get();
}
const DWARFDebugFrame *DWARFContext::getEHFrame() {
if (EHFrame)
return EHFrame.get();
DataExtractor debugFrameData(getEHFrameSection(), isLittleEndian(),
getAddressSize());
DebugFrame.reset(new DWARFDebugFrame(true /* IsEH */));
DebugFrame->parse(debugFrameData);
return DebugFrame.get();
}
const DWARFDebugMacro *DWARFContext::getDebugMacro() {
if (Macro)
return Macro.get();
DataExtractor MacinfoData(getMacinfoSection(), isLittleEndian(), 0);
Macro.reset(new DWARFDebugMacro());
Macro->parse(MacinfoData);
return Macro.get();
}
const DWARFLineTable *
DWARFContext::getLineTableForUnit(DWARFUnit *U) {
if (!Line)
Line.reset(new DWARFDebugLine(&getLineSection().Relocs));
auto UnitDIE = U->getUnitDIE();
if (!UnitDIE)
return nullptr;
auto Offset = toSectionOffset(UnitDIE.find(DW_AT_stmt_list));
if (!Offset)
return nullptr; // No line table for this compile unit.
uint32_t stmtOffset = *Offset + U->getLineTableOffset();
// See if the line table is cached.
if (const DWARFLineTable *lt = Line->getLineTable(stmtOffset))
return lt;
// Make sure the offset is good before we try to parse.
if (stmtOffset >= U->getLineSection().size())
return nullptr;
// We have to parse it first.
DataExtractor lineData(U->getLineSection(), isLittleEndian(),
U->getAddressByteSize());
return Line->getOrParseLineTable(lineData, stmtOffset);
}
void DWARFContext::parseCompileUnits() {
CUs.parse(*this, getInfoSection());
}
void DWARFContext::parseTypeUnits() {
if (!TUs.empty())
return;
for (const auto &I : getTypesSections()) {
TUs.emplace_back();
TUs.back().parse(*this, I.second);
}
}
void DWARFContext::parseDWOCompileUnits() {
DWOCUs.parseDWO(*this, getInfoDWOSection());
}
void DWARFContext::parseDWOTypeUnits() {
if (!DWOTUs.empty())
return;
for (const auto &I : getTypesDWOSections()) {
DWOTUs.emplace_back();
DWOTUs.back().parseDWO(*this, I.second);
}
}
DWARFCompileUnit *DWARFContext::getCompileUnitForOffset(uint32_t Offset) {
parseCompileUnits();
return CUs.getUnitForOffset(Offset);
}
DWARFCompileUnit *DWARFContext::getCompileUnitForAddress(uint64_t Address) {
// First, get the offset of the compile unit.
uint32_t CUOffset = getDebugAranges()->findAddress(Address);
// Retrieve the compile unit.
return getCompileUnitForOffset(CUOffset);
}
static bool getFunctionNameAndStartLineForAddress(DWARFCompileUnit *CU,
uint64_t Address,
FunctionNameKind Kind,
std::string &FunctionName,
uint32_t &StartLine) {
// The address may correspond to instruction in some inlined function,
// so we have to build the chain of inlined functions and take the
// name of the topmost function in it.
SmallVector<DWARFDie, 4> InlinedChain;
CU->getInlinedChainForAddress(Address, InlinedChain);
if (InlinedChain.empty())
return false;
const DWARFDie &DIE = InlinedChain[0];
bool FoundResult = false;
const char *Name = nullptr;
if (Kind != FunctionNameKind::None && (Name = DIE.getSubroutineName(Kind))) {
FunctionName = Name;
FoundResult = true;
}
if (auto DeclLineResult = DIE.getDeclLine()) {
StartLine = DeclLineResult;
FoundResult = true;
}
return FoundResult;
}
DILineInfo DWARFContext::getLineInfoForAddress(uint64_t Address,
DILineInfoSpecifier Spec) {
DILineInfo Result;
DWARFCompileUnit *CU = getCompileUnitForAddress(Address);
if (!CU)
return Result;
getFunctionNameAndStartLineForAddress(CU, Address, Spec.FNKind,
Result.FunctionName,
Result.StartLine);
if (Spec.FLIKind != FileLineInfoKind::None) {
if (const DWARFLineTable *LineTable = getLineTableForUnit(CU))
LineTable->getFileLineInfoForAddress(Address, CU->getCompilationDir(),
Spec.FLIKind, Result);
}
return Result;
}
DILineInfoTable
DWARFContext::getLineInfoForAddressRange(uint64_t Address, uint64_t Size,
DILineInfoSpecifier Spec) {
DILineInfoTable Lines;
DWARFCompileUnit *CU = getCompileUnitForAddress(Address);
if (!CU)
return Lines;
std::string FunctionName = "<invalid>";
uint32_t StartLine = 0;
getFunctionNameAndStartLineForAddress(CU, Address, Spec.FNKind, FunctionName,
StartLine);
// If the Specifier says we don't need FileLineInfo, just
// return the top-most function at the starting address.
if (Spec.FLIKind == FileLineInfoKind::None) {
DILineInfo Result;
Result.FunctionName = FunctionName;
Result.StartLine = StartLine;
Lines.push_back(std::make_pair(Address, Result));
return Lines;
}
const DWARFLineTable *LineTable = getLineTableForUnit(CU);
// Get the index of row we're looking for in the line table.
std::vector<uint32_t> RowVector;
if (!LineTable->lookupAddressRange(Address, Size, RowVector))
return Lines;
for (uint32_t RowIndex : RowVector) {
// Take file number and line/column from the row.
const DWARFDebugLine::Row &Row = LineTable->Rows[RowIndex];
DILineInfo Result;
LineTable->getFileNameByIndex(Row.File, CU->getCompilationDir(),
Spec.FLIKind, Result.FileName);
Result.FunctionName = FunctionName;
Result.Line = Row.Line;
Result.Column = Row.Column;
Result.StartLine = StartLine;
Lines.push_back(std::make_pair(Row.Address, Result));
}
return Lines;
}
DIInliningInfo
DWARFContext::getInliningInfoForAddress(uint64_t Address,
DILineInfoSpecifier Spec) {
DIInliningInfo InliningInfo;
DWARFCompileUnit *CU = getCompileUnitForAddress(Address);
if (!CU)
return InliningInfo;
const DWARFLineTable *LineTable = nullptr;
SmallVector<DWARFDie, 4> InlinedChain;
CU->getInlinedChainForAddress(Address, InlinedChain);
if (InlinedChain.size() == 0) {
// If there is no DIE for address (e.g. it is in unavailable .dwo file),
// try to at least get file/line info from symbol table.
if (Spec.FLIKind != FileLineInfoKind::None) {
DILineInfo Frame;
LineTable = getLineTableForUnit(CU);
if (LineTable &&
LineTable->getFileLineInfoForAddress(Address, CU->getCompilationDir(),
Spec.FLIKind, Frame))
InliningInfo.addFrame(Frame);
}
return InliningInfo;
}
uint32_t CallFile = 0, CallLine = 0, CallColumn = 0, CallDiscriminator = 0;
for (uint32_t i = 0, n = InlinedChain.size(); i != n; i++) {
DWARFDie &FunctionDIE = InlinedChain[i];
DILineInfo Frame;
// Get function name if necessary.
if (const char *Name = FunctionDIE.getSubroutineName(Spec.FNKind))
Frame.FunctionName = Name;
if (auto DeclLineResult = FunctionDIE.getDeclLine())
Frame.StartLine = DeclLineResult;
if (Spec.FLIKind != FileLineInfoKind::None) {
if (i == 0) {
// For the topmost frame, initialize the line table of this
// compile unit and fetch file/line info from it.
LineTable = getLineTableForUnit(CU);
// For the topmost routine, get file/line info from line table.
if (LineTable)
LineTable->getFileLineInfoForAddress(Address, CU->getCompilationDir(),
Spec.FLIKind, Frame);
} else {
// Otherwise, use call file, call line and call column from
// previous DIE in inlined chain.
if (LineTable)
LineTable->getFileNameByIndex(CallFile, CU->getCompilationDir(),
Spec.FLIKind, Frame.FileName);
Frame.Line = CallLine;
Frame.Column = CallColumn;
Frame.Discriminator = CallDiscriminator;
}
// Get call file/line/column of a current DIE.
if (i + 1 < n) {
FunctionDIE.getCallerFrame(CallFile, CallLine, CallColumn,
CallDiscriminator);
}
}
InliningInfo.addFrame(Frame);
}
return InliningInfo;
}
std::shared_ptr<DWARFContext>
DWARFContext::getDWOContext(StringRef AbsolutePath) {
if (auto S = DWP.lock()) {
DWARFContext *Ctxt = S->Context.get();
return std::shared_ptr<DWARFContext>(std::move(S), Ctxt);
}
std::weak_ptr<DWOFile> *Entry = &DWOFiles[AbsolutePath];
if (auto S = Entry->lock()) {
DWARFContext *Ctxt = S->Context.get();
return std::shared_ptr<DWARFContext>(std::move(S), Ctxt);
}
SmallString<128> DWPName;
Expected<OwningBinary<ObjectFile>> Obj = [&] {
if (!CheckedForDWP) {
(getFileName() + ".dwp").toVector(DWPName);
auto Obj = object::ObjectFile::createObjectFile(DWPName);
if (Obj) {
Entry = &DWP;
return Obj;
} else {
CheckedForDWP = true;
// TODO: Should this error be handled (maybe in a high verbosity mode)
// before falling back to .dwo files?
consumeError(Obj.takeError());
}
}
return object::ObjectFile::createObjectFile(AbsolutePath);
}();
if (!Obj) {
// TODO: Actually report errors helpfully.
consumeError(Obj.takeError());
return nullptr;
}
auto S = std::make_shared<DWOFile>();
S->File = std::move(Obj.get());
S->Context = llvm::make_unique<DWARFContextInMemory>(*S->File.getBinary());
*Entry = S;
auto *Ctxt = S->Context.get();
return std::shared_ptr<DWARFContext>(std::move(S), Ctxt);
}
static Error createError(const Twine &Reason, llvm::Error E) {
return make_error<StringError>(Reason + toString(std::move(E)),
inconvertibleErrorCode());
}
/// SymInfo contains information about symbol: it's address
/// and section index which is -1LL for absolute symbols.
struct SymInfo {
uint64_t Address;
uint64_t SectionIndex;
};
/// Returns the address of symbol relocation used against and a section index.
/// Used for futher relocations computation. Symbol's section load address is
static Expected<SymInfo> getSymbolInfo(const object::ObjectFile &Obj,
const RelocationRef &Reloc,
const LoadedObjectInfo *L,
std::map<SymbolRef, SymInfo> &Cache) {
SymInfo Ret = {0, (uint64_t)-1LL};
object::section_iterator RSec = Obj.section_end();
object::symbol_iterator Sym = Reloc.getSymbol();
std::map<SymbolRef, SymInfo>::iterator CacheIt = Cache.end();
// First calculate the address of the symbol or section as it appears
// in the object file
if (Sym != Obj.symbol_end()) {
bool New;
std::tie(CacheIt, New) = Cache.insert({*Sym, {0, 0}});
if (!New)
return CacheIt->second;
Expected<uint64_t> SymAddrOrErr = Sym->getAddress();
if (!SymAddrOrErr)
return createError("error: failed to compute symbol address: ",
SymAddrOrErr.takeError());
// Also remember what section this symbol is in for later
auto SectOrErr = Sym->getSection();
if (!SectOrErr)
return createError("error: failed to get symbol section: ",
SectOrErr.takeError());
RSec = *SectOrErr;
Ret.Address = *SymAddrOrErr;
} else if (auto *MObj = dyn_cast<MachOObjectFile>(&Obj)) {
RSec = MObj->getRelocationSection(Reloc.getRawDataRefImpl());
Ret.Address = RSec->getAddress();
}
if (RSec != Obj.section_end())
Ret.SectionIndex = RSec->getIndex();
// If we are given load addresses for the sections, we need to adjust:
// SymAddr = (Address of Symbol Or Section in File) -
// (Address of Section in File) +
// (Load Address of Section)
// RSec is now either the section being targeted or the section
// containing the symbol being targeted. In either case,
// we need to perform the same computation.
if (L && RSec != Obj.section_end())
if (uint64_t SectionLoadAddress = L->getSectionLoadAddress(*RSec))
Ret.Address += SectionLoadAddress - RSec->getAddress();
if (CacheIt != Cache.end())
CacheIt->second = Ret;
return Ret;
}
static bool isRelocScattered(const object::ObjectFile &Obj,
const RelocationRef &Reloc) {
const MachOObjectFile *MachObj = dyn_cast<MachOObjectFile>(&Obj);
if (!MachObj)
return false;
// MachO also has relocations that point to sections and
// scattered relocations.
auto RelocInfo = MachObj->getRelocation(Reloc.getRawDataRefImpl());
return MachObj->isRelocationScattered(RelocInfo);
}
Error DWARFContextInMemory::maybeDecompress(const SectionRef &Sec,
StringRef Name, StringRef &Data) {
if (!Decompressor::isCompressed(Sec))
return Error::success();
Expected<Decompressor> Decompressor =
Decompressor::create(Name, Data, IsLittleEndian, AddressSize == 8);
if (!Decompressor)
return Decompressor.takeError();
SmallString<32> Out;
if (auto Err = Decompressor->resizeAndDecompress(Out))
return Err;
UncompressedSections.emplace_back(std::move(Out));
Data = UncompressedSections.back();
return Error::success();
}
DWARFContextInMemory::DWARFContextInMemory(const object::ObjectFile &Obj,
const LoadedObjectInfo *L)
: FileName(Obj.getFileName()), IsLittleEndian(Obj.isLittleEndian()),
AddressSize(Obj.getBytesInAddress()) {
for (const SectionRef &Section : Obj.sections()) {
StringRef name;
Section.getName(name);
// Skip BSS and Virtual sections, they aren't interesting.
bool IsBSS = Section.isBSS();
if (IsBSS)
continue;
bool IsVirtual = Section.isVirtual();
if (IsVirtual)
continue;
StringRef data;
section_iterator RelocatedSection = Section.getRelocatedSection();
// Try to obtain an already relocated version of this section.
// Else use the unrelocated section from the object file. We'll have to
// apply relocations ourselves later.
if (!L || !L->getLoadedSectionContents(*RelocatedSection, data))
Section.getContents(data);
if (auto Err = maybeDecompress(Section, name, data)) {
errs() << "error: failed to decompress '" + name + "', " +
toString(std::move(Err))
<< '\n';
continue;
}
// Compressed sections names in GNU style starts from ".z",
// at this point section is decompressed and we drop compression prefix.
name = name.substr(
name.find_first_not_of("._z")); // Skip ".", "z" and "_" prefixes.
if (StringRef *SectionData = MapSectionToMember(name)) {
*SectionData = data;
if (name == "debug_ranges") {
// FIXME: Use the other dwo range section when we emit it.
RangeDWOSection.Data = data;
}
} else if (name == "debug_types") {
// Find debug_types data by section rather than name as there are
// multiple, comdat grouped, debug_types sections.
TypesSections[Section].Data = data;
} else if (name == "debug_types.dwo") {
TypesDWOSections[Section].Data = data;
}
if (RelocatedSection == Obj.section_end())
continue;
StringRef RelSecName;
StringRef RelSecData;
RelocatedSection->getName(RelSecName);
// If the section we're relocating was relocated already by the JIT,
// then we used the relocated version above, so we do not need to process
// relocations for it now.
if (L && L->getLoadedSectionContents(*RelocatedSection, RelSecData))
continue;
// In Mach-o files, the relocations do not need to be applied if
// there is no load offset to apply. The value read at the
// relocation point already factors in the section address
// (actually applying the relocations will produce wrong results
// as the section address will be added twice).
if (!L && isa<MachOObjectFile>(&Obj))
continue;
RelSecName = RelSecName.substr(
RelSecName.find_first_not_of("._")); // Skip . and _ prefixes.
// TODO: Add support for relocations in other sections as needed.
// Record relocations for the debug_info and debug_line sections.
RelocAddrMap *Map =
StringSwitch<RelocAddrMap *>(RelSecName)
.Case("debug_info", &InfoSection.Relocs)
.Case("debug_loc", &LocSection.Relocs)
.Case("debug_info.dwo", &InfoDWOSection.Relocs)
.Case("debug_line", &LineSection.Relocs)
.Case("debug_ranges", &RangeSection.Relocs)
.Case("debug_addr", &AddrSection.Relocs)
.Case("apple_names", &AppleNamesSection.Relocs)
.Case("apple_types", &AppleTypesSection.Relocs)
.Case("apple_namespaces", &AppleNamespacesSection.Relocs)
.Case("apple_namespac", &AppleNamespacesSection.Relocs)
.Case("apple_objc", &AppleObjCSection.Relocs)
.Default(nullptr);
if (!Map) {
// Find debug_types relocs by section rather than name as there are
// multiple, comdat grouped, debug_types sections.
if (RelSecName == "debug_types")
Map = &TypesSections[*RelocatedSection].Relocs;
else if (RelSecName == "debug_types.dwo")
Map = &TypesDWOSections[*RelocatedSection].Relocs;
else
continue;
}
if (Section.relocation_begin() == Section.relocation_end())
continue;
// Symbol to [address, section index] cache mapping.
std::map<SymbolRef, SymInfo> AddrCache;
for (const RelocationRef &Reloc : Section.relocations()) {
// FIXME: it's not clear how to correctly handle scattered
// relocations.
if (isRelocScattered(Obj, Reloc))
continue;
Expected<SymInfo> SymInfoOrErr = getSymbolInfo(Obj, Reloc, L, AddrCache);
if (!SymInfoOrErr) {
errs() << toString(SymInfoOrErr.takeError()) << '\n';
continue;
}
object::RelocVisitor V(Obj);
uint64_t Val = V.visit(Reloc.getType(), Reloc, SymInfoOrErr->Address);
if (V.error()) {
SmallString<32> Name;
Reloc.getTypeName(Name);
errs() << "error: failed to compute relocation: " << Name << "\n";
continue;
}
llvm::RelocAddrEntry Rel = {SymInfoOrErr->SectionIndex, Val};
Map->insert({Reloc.getOffset(), Rel});
}
}
}
DWARFContextInMemory::DWARFContextInMemory(
const StringMap<std::unique_ptr<MemoryBuffer>> &Sections, uint8_t AddrSize,
bool isLittleEndian)
: IsLittleEndian(isLittleEndian), AddressSize(AddrSize) {
for (const auto &SecIt : Sections) {
if (StringRef *SectionData = MapSectionToMember(SecIt.first()))
*SectionData = SecIt.second->getBuffer();
}
}
StringRef *DWARFContextInMemory::MapSectionToMember(StringRef Name) {
return StringSwitch<StringRef *>(Name)
.Case("debug_info", &InfoSection.Data)
.Case("debug_abbrev", &AbbrevSection)
.Case("debug_loc", &LocSection.Data)
.Case("debug_line", &LineSection.Data)
.Case("debug_aranges", &ARangeSection)
.Case("debug_frame", &DebugFrameSection)
.Case("eh_frame", &EHFrameSection)
.Case("debug_str", &StringSection)
.Case("debug_ranges", &RangeSection.Data)
.Case("debug_macinfo", &MacinfoSection)
.Case("debug_pubnames", &PubNamesSection)
.Case("debug_pubtypes", &PubTypesSection)
.Case("debug_gnu_pubnames", &GnuPubNamesSection)
.Case("debug_gnu_pubtypes", &GnuPubTypesSection)
.Case("debug_info.dwo", &InfoDWOSection.Data)
.Case("debug_abbrev.dwo", &AbbrevDWOSection)
.Case("debug_loc.dwo", &LocDWOSection.Data)
.Case("debug_line.dwo", &LineDWOSection.Data)
.Case("debug_str.dwo", &StringDWOSection)
.Case("debug_str_offsets.dwo", &StringOffsetDWOSection)
.Case("debug_addr", &AddrSection.Data)
.Case("apple_names", &AppleNamesSection.Data)
.Case("apple_types", &AppleTypesSection.Data)
.Case("apple_namespaces", &AppleNamespacesSection.Data)
.Case("apple_namespac", &AppleNamespacesSection.Data)
.Case("apple_objc", &AppleObjCSection.Data)
.Case("debug_cu_index", &CUIndexSection)
.Case("debug_tu_index", &TUIndexSection)
.Case("gdb_index", &GdbIndexSection)
// Any more debug info sections go here.
.Default(nullptr);
}
void DWARFContextInMemory::anchor() {}
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