Google Git
Sign in
llvm / llvm-project / llvm / 5c4b039b3e40c0c4f3ccfbbe875ca6a406e28206 / . / tools / dsymutil / DwarfLinkerForBinary.cpp
blob: 5331eabf89a167b53b487fe530ebef0b20ba73f5 [file] [log] [blame]
//===- tools/dsymutil/DwarfLinkerForBinary.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 "DwarfLinkerForBinary.h"
#include "BinaryHolder.h"
#include "DebugMap.h"
#include "MachOUtils.h"
#include "dsymutil.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/BitVector.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/DenseMapInfo.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/FoldingSet.h"
#include "llvm/ADT/Hashing.h"
#include "llvm/ADT/PointerIntPair.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/Twine.h"
#include "llvm/BinaryFormat/Dwarf.h"
#include "llvm/BinaryFormat/MachO.h"
#include "llvm/BinaryFormat/Swift.h"
#include "llvm/CodeGen/AccelTable.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/DIE.h"
#include "llvm/CodeGen/NonRelocatableStringpool.h"
#include "llvm/Config/config.h"
#include "llvm/DWARFLinker/DWARFLinkerDeclContext.h"
#include "llvm/DWARFLinkerParallel/DWARFLinker.h"
#include "llvm/DebugInfo/DIContext.h"
#include "llvm/DebugInfo/DWARF/DWARFAbbreviationDeclaration.h"
#include "llvm/DebugInfo/DWARF/DWARFContext.h"
#include "llvm/DebugInfo/DWARF/DWARFDataExtractor.h"
#include "llvm/DebugInfo/DWARF/DWARFDebugLine.h"
#include "llvm/DebugInfo/DWARF/DWARFDebugRangeList.h"
#include "llvm/DebugInfo/DWARF/DWARFDie.h"
#include "llvm/DebugInfo/DWARF/DWARFExpression.h"
#include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
#include "llvm/DebugInfo/DWARF/DWARFSection.h"
#include "llvm/DebugInfo/DWARF/DWARFUnit.h"
#include "llvm/MC/MCAsmBackend.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCCodeEmitter.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCDwarf.h"
#include "llvm/MC/MCInstrInfo.h"
#include "llvm/MC/MCObjectFileInfo.h"
#include "llvm/MC/MCObjectWriter.h"
#include "llvm/MC/MCRegisterInfo.h"
#include "llvm/MC/MCSection.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSubtargetInfo.h"
#include "llvm/MC/MCTargetOptions.h"
#include "llvm/MC/MCTargetOptionsCommandFlags.h"
#include "llvm/MC/TargetRegistry.h"
#include "llvm/Object/MachO.h"
#include "llvm/Object/ObjectFile.h"
#include "llvm/Object/SymbolicFile.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/DJB.h"
#include "llvm/Support/DataExtractor.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/ErrorOr.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/LEB128.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/ThreadPool.h"
#include "llvm/Support/ToolOutputFile.h"
#include "llvm/Support/WithColor.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/TargetParser/Triple.h"
#include <algorithm>
#include <cassert>
#include <cinttypes>
#include <climits>
#include <cstdint>
#include <cstdlib>
#include <cstring>
#include <limits>
#include <map>
#include <memory>
#include <optional>
#include <string>
#include <system_error>
#include <tuple>
#include <utility>
#include <vector>
namespace llvm {
static mc::RegisterMCTargetOptionsFlags MOF;
namespace dsymutil {
static void dumpDIE(const DWARFDie *DIE, bool Verbose) {
if (!DIE || !Verbose)
return;
DIDumpOptions DumpOpts;
DumpOpts.ChildRecurseDepth = 0;
DumpOpts.Verbose = Verbose;
WithColor::note() << " in DIE:\n";
DIE->dump(errs(), 6 /* Indent */, DumpOpts);
}
/// Report a warning to the user, optionally including information about a
/// specific \p DIE related to the warning.
void DwarfLinkerForBinary::reportWarning(Twine Warning, Twine Context,
const DWARFDie *DIE) const {
std::lock_guard<std::mutex> Guard(ErrorHandlerMutex);
warn(Warning, Context);
dumpDIE(DIE, Options.Verbose);
}
void DwarfLinkerForBinary::reportError(Twine Error, Twine Context,
const DWARFDie *DIE) const {
std::lock_guard<std::mutex> Guard(ErrorHandlerMutex);
error(Error, Context);
dumpDIE(DIE, Options.Verbose);
}
ErrorOr<const object::ObjectFile &>
DwarfLinkerForBinary::loadObject(const DebugMapObject &Obj,
const Triple &Triple) {
auto ObjectEntry =
BinHolder.getObjectEntry(Obj.getObjectFilename(), Obj.getTimestamp());
if (!ObjectEntry) {
auto Err = ObjectEntry.takeError();
reportWarning(Twine(Obj.getObjectFilename()) + ": " +
toString(std::move(Err)),
Obj.getObjectFilename());
return errorToErrorCode(std::move(Err));
}
auto Object = ObjectEntry->getObject(Triple);
if (!Object) {
auto Err = Object.takeError();
reportWarning(Twine(Obj.getObjectFilename()) + ": " +
toString(std::move(Err)),
Obj.getObjectFilename());
return errorToErrorCode(std::move(Err));
}
return *Object;
}
static Error remarksErrorHandler(const DebugMapObject &DMO,
DwarfLinkerForBinary &Linker,
std::unique_ptr<FileError> FE) {
bool IsArchive = DMO.getObjectFilename().endswith(")");
// Don't report errors for missing remark files from static
// archives.
if (!IsArchive)
return Error(std::move(FE));
std::string Message = FE->message();
Error E = FE->takeError();
Error NewE = handleErrors(std::move(E), [&](std::unique_ptr<ECError> EC) {
if (EC->convertToErrorCode() != std::errc::no_such_file_or_directory)
return Error(std::move(EC));
Linker.reportWarning(Message, DMO.getObjectFilename());
return Error(Error::success());
});
if (!NewE)
return Error::success();
return createFileError(FE->getFileName(), std::move(NewE));
}
static Error emitRemarks(const LinkOptions &Options, StringRef BinaryPath,
StringRef ArchName, const remarks::RemarkLinker &RL) {
// Make sure we don't create the directories and the file if there is nothing
// to serialize.
if (RL.empty())
return Error::success();
SmallString<128> InputPath;
SmallString<128> Path;
// Create the "Remarks" directory in the "Resources" directory.
sys::path::append(Path, *Options.ResourceDir, "Remarks");
if (std::error_code EC = sys::fs::create_directories(Path.str(), true,
sys::fs::perms::all_all))
return errorCodeToError(EC);
// Append the file name.
// For fat binaries, also append a dash and the architecture name.
sys::path::append(Path, sys::path::filename(BinaryPath));
if (Options.NumDebugMaps > 1) {
// More than one debug map means we have a fat binary.
Path += '-';
Path += ArchName;
}
std::error_code EC;
raw_fd_ostream OS(Options.NoOutput ? "-" : Path.str(), EC,
Options.RemarksFormat == remarks::Format::Bitstream
? sys::fs::OF_None
: sys::fs::OF_Text);
if (EC)
return errorCodeToError(EC);
if (Error E = RL.serialize(OS, Options.RemarksFormat))
return E;
return Error::success();
}
template <typename OutDWARFFile, typename AddressesMap>
ErrorOr<std::unique_ptr<OutDWARFFile>>
DwarfLinkerForBinary::loadObject(const DebugMapObject &Obj,
const DebugMap &DebugMap,
remarks::RemarkLinker &RL) {
auto ErrorOrObj = loadObject(Obj, DebugMap.getTriple());
std::unique_ptr<OutDWARFFile> Res;
if (ErrorOrObj) {
Res = std::make_unique<OutDWARFFile>(
Obj.getObjectFilename(), DWARFContext::create(*ErrorOrObj),
std::make_unique<AddressesMap>(*this, *ErrorOrObj, Obj),
Obj.empty() ? Obj.getWarnings() : EmptyWarnings);
Error E = RL.link(*ErrorOrObj);
if (Error NewE = handleErrors(
std::move(E), [&](std::unique_ptr<FileError> EC) -> Error {
return remarksErrorHandler(Obj, *this, std::move(EC));
}))
return errorToErrorCode(std::move(NewE));
return Res;
}
return ErrorOrObj.getError();
}
static bool binaryHasStrippableSwiftReflectionSections(
const DebugMap &Map, const LinkOptions &Options, BinaryHolder &BinHolder) {
// If the input binary has strippable swift5 reflection sections, there is no
// need to copy them to the .dSYM. Only copy them for binaries where the
// linker omitted the reflection metadata.
if (!Map.getBinaryPath().empty() &&
Options.FileType == DWARFLinker::OutputFileType::Object) {
auto ObjectEntry = BinHolder.getObjectEntry(Map.getBinaryPath());
// If ObjectEntry or Object has an error, no binary exists, therefore no
// reflection sections exist.
if (!ObjectEntry) {
// Any errors will be diagnosed later in the main loop, ignore them here.
llvm::consumeError(ObjectEntry.takeError());
return false;
}
auto Object =
ObjectEntry->getObjectAs<object::MachOObjectFile>(Map.getTriple());
if (!Object) {
// Any errors will be diagnosed later in the main loop, ignore them here.
llvm::consumeError(Object.takeError());
return false;
}
for (auto &Section : Object->sections()) {
llvm::Expected<llvm::StringRef> NameOrErr =
Object->getSectionName(Section.getRawDataRefImpl());
if (!NameOrErr) {
llvm::consumeError(NameOrErr.takeError());
continue;
}
NameOrErr->consume_back("__TEXT");
auto ReflectionSectionKind =
Object->mapReflectionSectionNameToEnumValue(*NameOrErr);
if (Object->isReflectionSectionStrippable(ReflectionSectionKind)) {
return true;
}
}
}
return false;
}
/// Calculate the start of the strippable swift reflection sections in Dwarf.
/// Note that there's an assumption that the reflection sections will appear
/// in alphabetic order.
static std::vector<uint64_t>
calculateStartOfStrippableReflectionSections(const DebugMap &Map) {
using llvm::binaryformat::Swift5ReflectionSectionKind;
uint64_t AssocTySize = 0;
uint64_t FieldMdSize = 0;
for (const auto &Obj : Map.objects()) {
auto OF =
llvm::object::ObjectFile::createObjectFile(Obj->getObjectFilename());
if (!OF) {
llvm::consumeError(OF.takeError());
continue;
}
if (auto *MO = dyn_cast<llvm::object::MachOObjectFile>(OF->getBinary())) {
for (auto &Section : MO->sections()) {
llvm::Expected<llvm::StringRef> NameOrErr =
MO->getSectionName(Section.getRawDataRefImpl());
if (!NameOrErr) {
llvm::consumeError(NameOrErr.takeError());
continue;
}
NameOrErr->consume_back("__TEXT");
auto ReflSectionKind =
MO->mapReflectionSectionNameToEnumValue(*NameOrErr);
switch (ReflSectionKind) {
case Swift5ReflectionSectionKind::assocty:
AssocTySize += Section.getSize();
break;
case Swift5ReflectionSectionKind::fieldmd:
FieldMdSize += Section.getSize();
break;
default:
break;
}
}
}
}
// Initialize the vector with enough space to fit every reflection section
// kind.
std::vector<uint64_t> SectionToOffset(Swift5ReflectionSectionKind::last, 0);
SectionToOffset[Swift5ReflectionSectionKind::assocty] = 0;
SectionToOffset[Swift5ReflectionSectionKind::fieldmd] =
llvm::alignTo(AssocTySize, 4);
SectionToOffset[Swift5ReflectionSectionKind::reflstr] = llvm::alignTo(
SectionToOffset[Swift5ReflectionSectionKind::fieldmd] + FieldMdSize, 4);
return SectionToOffset;
}
void DwarfLinkerForBinary::collectRelocationsToApplyToSwiftReflectionSections(
const object::SectionRef &Section, StringRef &Contents,
const llvm::object::MachOObjectFile *MO,
const std::vector<uint64_t> &SectionToOffsetInDwarf,
const llvm::dsymutil::DebugMapObject *Obj,
std::vector<MachOUtils::DwarfRelocationApplicationInfo> &RelocationsToApply)
const {
for (auto It = Section.relocation_begin(); It != Section.relocation_end();
++It) {
object::DataRefImpl RelocDataRef = It->getRawDataRefImpl();
MachO::any_relocation_info MachOReloc = MO->getRelocation(RelocDataRef);
if (!object::MachOObjectFile::isMachOPairedReloc(
MO->getAnyRelocationType(MachOReloc), MO->getArch())) {
reportWarning(
"Unimplemented relocation type in strippable reflection section ",
Obj->getObjectFilename());
continue;
}
auto CalculateAddressOfSymbolInDwarfSegment =
[&]() -> std::optional<int64_t> {
auto Symbol = It->getSymbol();
auto SymbolAbsoluteAddress = Symbol->getAddress();
if (!SymbolAbsoluteAddress)
return {};
auto Section = Symbol->getSection();
if (!Section) {
llvm::consumeError(Section.takeError());
return {};
}
if ((*Section)->getObject()->section_end() == *Section)
return {};
auto SectionStart = (*Section)->getAddress();
auto SymbolAddressInSection = *SymbolAbsoluteAddress - SectionStart;
auto SectionName = (*Section)->getName();
if (!SectionName)
return {};
auto ReflSectionKind =
MO->mapReflectionSectionNameToEnumValue(*SectionName);
int64_t SectionStartInLinkedBinary =
SectionToOffsetInDwarf[ReflSectionKind];
auto Addr = SectionStartInLinkedBinary + SymbolAddressInSection;
return Addr;
};
// The first symbol should always be in the section we're currently
// iterating over.
auto FirstSymbolAddress = CalculateAddressOfSymbolInDwarfSegment();
++It;
bool ShouldSubtractDwarfVM = false;
// For the second symbol there are two possibilities.
std::optional<int64_t> SecondSymbolAddress;
auto Sym = It->getSymbol();
if (Sym != MO->symbol_end()) {
Expected<StringRef> SymbolName = Sym->getName();
if (SymbolName) {
if (const auto *Mapping = Obj->lookupSymbol(*SymbolName)) {
// First possibility: the symbol exists in the binary, and exists in a
// non-strippable section (for example, typeref, or __TEXT,__const),
// in which case we look up its address in the binary, which dsymutil
// will copy verbatim.
SecondSymbolAddress = Mapping->getValue().BinaryAddress;
// Since the symbols live in different segments, we have to substract
// the start of the Dwarf's vmaddr so the value calculated points to
// the correct place.
ShouldSubtractDwarfVM = true;
}
}
}
if (!SecondSymbolAddress) {
// Second possibility, this symbol is not present in the main binary, and
// must be in one of the strippable sections (for example, reflstr).
// Calculate its address in the same way as we did the first one.
SecondSymbolAddress = CalculateAddressOfSymbolInDwarfSegment();
}
if (!FirstSymbolAddress || !SecondSymbolAddress)
continue;
auto SectionName = Section.getName();
if (!SectionName)
continue;
int32_t Addend;
memcpy(&Addend, Contents.data() + It->getOffset(), sizeof(int32_t));
int32_t Value = (*SecondSymbolAddress + Addend) - *FirstSymbolAddress;
auto ReflSectionKind =
MO->mapReflectionSectionNameToEnumValue(*SectionName);
uint64_t AddressFromDwarfVM =
SectionToOffsetInDwarf[ReflSectionKind] + It->getOffset();
RelocationsToApply.emplace_back(AddressFromDwarfVM, Value,
ShouldSubtractDwarfVM);
}
}
Error DwarfLinkerForBinary::copySwiftInterfaces(StringRef Architecture) const {
std::error_code EC;
SmallString<128> InputPath;
SmallString<128> Path;
sys::path::append(Path, *Options.ResourceDir, "Swift", Architecture);
if ((EC = sys::fs::create_directories(Path.str(), true,
sys::fs::perms::all_all)))
return make_error<StringError>(
"cannot create directory: " + toString(errorCodeToError(EC)), EC);
unsigned BaseLength = Path.size();
for (auto &I : ParseableSwiftInterfaces) {
StringRef ModuleName = I.first;
StringRef InterfaceFile = I.second;
if (!Options.PrependPath.empty()) {
InputPath.clear();
sys::path::append(InputPath, Options.PrependPath, InterfaceFile);
InterfaceFile = InputPath;
}
sys::path::append(Path, ModuleName);
Path.append(".swiftinterface");
if (Options.Verbose)
outs() << "copy parseable Swift interface " << InterfaceFile << " -> "
<< Path.str() << '\n';
// copy_file attempts an APFS clone first, so this should be cheap.
if ((EC = sys::fs::copy_file(InterfaceFile, Path.str())))
reportWarning(Twine("cannot copy parseable Swift interface ") +
InterfaceFile + ": " + toString(errorCodeToError(EC)));
Path.resize(BaseLength);
}
return Error::success();
}
template <typename OutStreamer>
void DwarfLinkerForBinary::copySwiftReflectionMetadata(
const llvm::dsymutil::DebugMapObject *Obj, OutStreamer *Streamer,
std::vector<uint64_t> &SectionToOffsetInDwarf,
std::vector<MachOUtils::DwarfRelocationApplicationInfo>
&RelocationsToApply) {
using binaryformat::Swift5ReflectionSectionKind;
auto OF =
llvm::object::ObjectFile::createObjectFile(Obj->getObjectFilename());
if (!OF) {
llvm::consumeError(OF.takeError());
return;
}
if (auto *MO = dyn_cast<llvm::object::MachOObjectFile>(OF->getBinary())) {
// Collect the swift reflection sections before emitting them. This is
// done so we control the order they're emitted.
std::array<std::optional<object::SectionRef>,
Swift5ReflectionSectionKind::last + 1>
SwiftSections;
for (auto &Section : MO->sections()) {
llvm::Expected<llvm::StringRef> NameOrErr =
MO->getSectionName(Section.getRawDataRefImpl());
if (!NameOrErr) {
llvm::consumeError(NameOrErr.takeError());
continue;
}
NameOrErr->consume_back("__TEXT");
auto ReflSectionKind =
MO->mapReflectionSectionNameToEnumValue(*NameOrErr);
if (MO->isReflectionSectionStrippable(ReflSectionKind))
SwiftSections[ReflSectionKind] = Section;
}
// Make sure we copy the sections in alphabetic order.
auto SectionKindsToEmit = {Swift5ReflectionSectionKind::assocty,
Swift5ReflectionSectionKind::fieldmd,
Swift5ReflectionSectionKind::reflstr};
for (auto SectionKind : SectionKindsToEmit) {
if (!SwiftSections[SectionKind])
continue;
auto &Section = *SwiftSections[SectionKind];
llvm::Expected<llvm::StringRef> SectionContents = Section.getContents();
if (!SectionContents)
continue;
const auto *MO =
llvm::cast<llvm::object::MachOObjectFile>(Section.getObject());
collectRelocationsToApplyToSwiftReflectionSections(
Section, *SectionContents, MO, SectionToOffsetInDwarf, Obj,
RelocationsToApply);
// Update the section start with the current section's contribution, so
// the next section we copy from a different .o file points to the correct
// place.
SectionToOffsetInDwarf[SectionKind] += Section.getSize();
Streamer->emitSwiftReflectionSection(SectionKind, *SectionContents,
Section.getAlignment().value(),
Section.getSize());
}
}
}
bool DwarfLinkerForBinary::link(const DebugMap &Map) {
if (Options.DWARFLinkerType == DsymutilDWARFLinkerType::LLVM) {
dwarflinker_parallel::DWARFLinker::OutputFileType DWARFLinkerOutputType;
switch (Options.FileType) {
case DWARFLinker::OutputFileType::Object:
DWARFLinkerOutputType =
dwarflinker_parallel::DWARFLinker::OutputFileType::Object;
break;
case DWARFLinker::OutputFileType::Assembly:
DWARFLinkerOutputType =
dwarflinker_parallel::DWARFLinker::OutputFileType::Assembly;
break;
}
return linkImpl<dwarflinker_parallel::DWARFLinker,
dwarflinker_parallel::DWARFFile,
AddressManager<dwarflinker_parallel::AddressesMap>>(
Map, DWARFLinkerOutputType);
}
return linkImpl<DWARFLinker, DWARFFile, AddressManager<AddressesMap>>(
Map, Options.FileType);
}
template <typename Linker>
void setAcceleratorTables(Linker &GeneralLinker,
DsymutilAccelTableKind TableKind,
uint16_t MaxDWARFVersion) {
switch (TableKind) {
case DsymutilAccelTableKind::Apple:
GeneralLinker.addAccelTableKind(Linker::AccelTableKind::Apple);
return;
case DsymutilAccelTableKind::Dwarf:
GeneralLinker.addAccelTableKind(Linker::AccelTableKind::DebugNames);
return;
case DsymutilAccelTableKind::Pub:
GeneralLinker.addAccelTableKind(Linker::AccelTableKind::Pub);
return;
case DsymutilAccelTableKind::Default:
if (MaxDWARFVersion >= 5)
GeneralLinker.addAccelTableKind(Linker::AccelTableKind::DebugNames);
else
GeneralLinker.addAccelTableKind(Linker::AccelTableKind::Apple);
return;
case DsymutilAccelTableKind::None:
// Nothing to do.
return;
}
llvm_unreachable("All cases handled above!");
}
template <typename Linker, typename OutDwarfFile, typename AddressMap>
bool DwarfLinkerForBinary::linkImpl(
const DebugMap &Map, typename Linker::OutputFileType ObjectType) {
std::vector<std::unique_ptr<OutDwarfFile>> ObjectsForLinking;
DebugMap DebugMap(Map.getTriple(), Map.getBinaryPath());
std::function<StringRef(StringRef)> TranslationLambda = [&](StringRef Input) {
assert(Options.Translator);
return Options.Translator(Input);
};
std::unique_ptr<Linker> GeneralLinker = Linker::createLinker(
[&](const Twine &Error, StringRef Context, const DWARFDie *DIE) {
reportError(Error, Context, DIE);
},
[&](const Twine &Warning, StringRef Context, const DWARFDie *DIE) {
reportWarning(Warning, Context, DIE);
},
Options.Translator ? TranslationLambda : nullptr);
if (!Options.NoOutput) {
if (Error Err = GeneralLinker->createEmitter(Map.getTriple(), ObjectType,
OutFile)) {
handleAllErrors(std::move(Err), [&](const ErrorInfoBase &EI) {
reportError(EI.message(), "dwarf streamer init");
});
return false;
}
}
remarks::RemarkLinker RL;
if (!Options.RemarksPrependPath.empty())
RL.setExternalFilePrependPath(Options.RemarksPrependPath);
RL.setKeepAllRemarks(Options.RemarksKeepAll);
GeneralLinker->setObjectPrefixMap(&Options.ObjectPrefixMap);
GeneralLinker->setVerbosity(Options.Verbose);
GeneralLinker->setStatistics(Options.Statistics);
GeneralLinker->setVerifyInputDWARF(Options.VerifyInputDWARF);
GeneralLinker->setNoODR(Options.NoODR);
GeneralLinker->setUpdateIndexTablesOnly(Options.Update);
GeneralLinker->setNumThreads(Options.Threads);
GeneralLinker->setPrependPath(Options.PrependPath);
GeneralLinker->setKeepFunctionForStatic(Options.KeepFunctionForStatic);
GeneralLinker->setInputVerificationHandler([&](const OutDwarfFile &File) {
reportWarning("input verification failed", File.FileName);
HasVerificationErrors = true;
});
auto Loader = [&](StringRef ContainerName,
StringRef Path) -> ErrorOr<OutDwarfFile &> {
auto &Obj = DebugMap.addDebugMapObject(
Path, sys::TimePoint<std::chrono::seconds>(), MachO::N_OSO);
if (ErrorOr<std::unique_ptr<OutDwarfFile>> ErrorOrObj =
loadObject<OutDwarfFile, AddressMap>(Obj, DebugMap, RL)) {
ObjectsForLinking.emplace_back(std::move(*ErrorOrObj));
return *ObjectsForLinking.back();
} else {
// Try and emit more helpful warnings by applying some heuristics.
StringRef ObjFile = ContainerName;
bool IsClangModule = sys::path::extension(Path).equals(".pcm");
bool IsArchive = ObjFile.endswith(")");
if (IsClangModule) {
StringRef ModuleCacheDir = sys::path::parent_path(Path);
if (sys::fs::exists(ModuleCacheDir)) {
// If the module's parent directory exists, we assume that the
// module cache has expired and was pruned by clang. A more
// adventurous dsymutil would invoke clang to rebuild the module
// now.
if (!ModuleCacheHintDisplayed) {
WithColor::note()
<< "The clang module cache may have expired since "
"this object file was built. Rebuilding the "
"object file will rebuild the module cache.\n";
ModuleCacheHintDisplayed = true;
}
} else if (IsArchive) {
// If the module cache directory doesn't exist at all and the
// object file is inside a static library, we assume that the
// static library was built on a different machine. We don't want
// to discourage module debugging for convenience libraries within
// a project though.
if (!ArchiveHintDisplayed) {
WithColor::note()
<< "Linking a static library that was built with "
"-gmodules, but the module cache was not found. "
"Redistributable static libraries should never be "
"built with module debugging enabled. The debug "
"experience will be degraded due to incomplete "
"debug information.\n";
ArchiveHintDisplayed = true;
}
}
}
return ErrorOrObj.getError();
}
llvm_unreachable("Unhandled DebugMap object");
};
GeneralLinker->setSwiftInterfacesMap(&ParseableSwiftInterfaces);
bool ReflectionSectionsPresentInBinary = false;
// If there is no output specified, no point in checking the binary for swift5
// reflection sections.
if (!Options.NoOutput) {
ReflectionSectionsPresentInBinary =
binaryHasStrippableSwiftReflectionSections(Map, Options, BinHolder);
}
std::vector<MachOUtils::DwarfRelocationApplicationInfo> RelocationsToApply;
if (!Options.NoOutput && !ReflectionSectionsPresentInBinary) {
auto SectionToOffsetInDwarf =
calculateStartOfStrippableReflectionSections(Map);
for (const auto &Obj : Map.objects())
copySwiftReflectionMetadata(Obj.get(), GeneralLinker->getEmitter(),
SectionToOffsetInDwarf, RelocationsToApply);
}
uint16_t MaxDWARFVersion = 0;
std::function<void(const DWARFUnit &Unit)> OnCUDieLoaded =
[&MaxDWARFVersion](const DWARFUnit &Unit) {
MaxDWARFVersion = std::max(Unit.getVersion(), MaxDWARFVersion);
};
for (const auto &Obj : Map.objects()) {
// N_AST objects (swiftmodule files) should get dumped directly into the
// appropriate DWARF section.
if (Obj->getType() == MachO::N_AST) {
if (Options.Verbose)
outs() << "DEBUG MAP OBJECT: " << Obj->getObjectFilename() << "\n";
StringRef File = Obj->getObjectFilename();
auto ErrorOrMem = MemoryBuffer::getFile(File);
if (!ErrorOrMem) {
reportWarning("Could not open '" + File + "'");
continue;
}
sys::fs::file_status Stat;
if (auto Err = sys::fs::status(File, Stat)) {
reportWarning(Err.message());
continue;
}
if (!Options.NoTimestamp) {
// The modification can have sub-second precision so we need to cast
// away the extra precision that's not present in the debug map.
auto ModificationTime =
std::chrono::time_point_cast<std::chrono::seconds>(
Stat.getLastModificationTime());
if (Obj->getTimestamp() != sys::TimePoint<>() &&
ModificationTime != Obj->getTimestamp()) {
// Not using the helper here as we can easily stream TimePoint<>.
WithColor::warning()
<< File << ": timestamp mismatch between swift interface file ("
<< sys::TimePoint<>(ModificationTime) << ") and debug map ("
<< sys::TimePoint<>(Obj->getTimestamp()) << ")\n";
continue;
}
}
// Copy the module into the .swift_ast section.
if (!Options.NoOutput)
GeneralLinker->getEmitter()->emitSwiftAST((*ErrorOrMem)->getBuffer());
continue;
}
if (ErrorOr<std::unique_ptr<OutDwarfFile>> ErrorOrObj =
loadObject<OutDwarfFile, AddressMap>(*Obj, Map, RL)) {
ObjectsForLinking.emplace_back(std::move(*ErrorOrObj));
GeneralLinker->addObjectFile(*ObjectsForLinking.back(), Loader,
OnCUDieLoaded);
} else {
ObjectsForLinking.push_back(std::make_unique<OutDwarfFile>(
Obj->getObjectFilename(), nullptr, nullptr,
Obj->empty() ? Obj->getWarnings() : EmptyWarnings));
GeneralLinker->addObjectFile(*ObjectsForLinking.back());
}
}
// If we haven't seen any CUs, pick an arbitrary valid Dwarf version anyway.
if (MaxDWARFVersion == 0)
MaxDWARFVersion = 3;
if (Error E = GeneralLinker->setTargetDWARFVersion(MaxDWARFVersion))
return error(toString(std::move(E)));
setAcceleratorTables<Linker>(*GeneralLinker, Options.TheAccelTableKind,
MaxDWARFVersion);
// link debug info for loaded object files.
if (Error E = GeneralLinker->link())
return error(toString(std::move(E)));
StringRef ArchName = Map.getTriple().getArchName();
if (Error E = emitRemarks(Options, Map.getBinaryPath(), ArchName, RL))
return error(toString(std::move(E)));
if (Options.NoOutput)
return true;
if (Options.ResourceDir && !ParseableSwiftInterfaces.empty()) {
StringRef ArchName = Triple::getArchTypeName(Map.getTriple().getArch());
if (auto E = copySwiftInterfaces(ArchName))
return error(toString(std::move(E)));
}
if (Map.getTriple().isOSDarwin() && !Map.getBinaryPath().empty() &&
ObjectType == Linker::OutputFileType::Object)
return MachOUtils::generateDsymCompanion(
Options.VFS, Map, Options.Translator,
*GeneralLinker->getEmitter()->getAsmPrinter().OutStreamer, OutFile,
RelocationsToApply);
GeneralLinker->getEmitter()->finish();
return true;
}
/// Iterate over the relocations of the given \p Section and
/// store the ones that correspond to debug map entries into the
/// ValidRelocs array.
template <typename AddressesMapBase>
void DwarfLinkerForBinary::AddressManager<AddressesMapBase>::
findValidRelocsMachO(const object::SectionRef &Section,
const object::MachOObjectFile &Obj,
const DebugMapObject &DMO,
std::vector<ValidReloc> &ValidRelocs) {
Expected<StringRef> ContentsOrErr = Section.getContents();
if (!ContentsOrErr) {
consumeError(ContentsOrErr.takeError());
Linker.reportWarning("error reading section", DMO.getObjectFilename());
return;
}
DataExtractor Data(*ContentsOrErr, Obj.isLittleEndian(), 0);
bool SkipNext = false;
for (const object::RelocationRef &Reloc : Section.relocations()) {
if (SkipNext) {
SkipNext = false;
continue;
}
object::DataRefImpl RelocDataRef = Reloc.getRawDataRefImpl();
MachO::any_relocation_info MachOReloc = Obj.getRelocation(RelocDataRef);
if (object::MachOObjectFile::isMachOPairedReloc(Obj.getAnyRelocationType(MachOReloc),
Obj.getArch())) {
SkipNext = true;
Linker.reportWarning("unsupported relocation in " + *Section.getName() +
" section.",
DMO.getObjectFilename());
continue;
}
unsigned RelocSize = 1 << Obj.getAnyRelocationLength(MachOReloc);
uint64_t Offset64 = Reloc.getOffset();
if ((RelocSize != 4 && RelocSize != 8)) {
Linker.reportWarning("unsupported relocation in " + *Section.getName() +
" section.",
DMO.getObjectFilename());
continue;
}
uint64_t OffsetCopy = Offset64;
// Mach-o uses REL relocations, the addend is at the relocation offset.
uint64_t Addend = Data.getUnsigned(&OffsetCopy, RelocSize);
uint64_t SymAddress;
int64_t SymOffset;
if (Obj.isRelocationScattered(MachOReloc)) {
// The address of the base symbol for scattered relocations is
// stored in the reloc itself. The actual addend will store the
// base address plus the offset.
SymAddress = Obj.getScatteredRelocationValue(MachOReloc);
SymOffset = int64_t(Addend) - SymAddress;
} else {
SymAddress = Addend;
SymOffset = 0;
}
auto Sym = Reloc.getSymbol();
if (Sym != Obj.symbol_end()) {
Expected<StringRef> SymbolName = Sym->getName();
if (!SymbolName) {
consumeError(SymbolName.takeError());
Linker.reportWarning("error getting relocation symbol name.",
DMO.getObjectFilename());
continue;
}
if (const auto *Mapping = DMO.lookupSymbol(*SymbolName))
ValidRelocs.emplace_back(Offset64, RelocSize, Addend, Mapping);
} else if (const auto *Mapping = DMO.lookupObjectAddress(SymAddress)) {
// Do not store the addend. The addend was the address of the symbol in
// the object file, the address in the binary that is stored in the debug
// map doesn't need to be offset.
ValidRelocs.emplace_back(Offset64, RelocSize, SymOffset, Mapping);
}
}
}
/// Dispatch the valid relocation finding logic to the
/// appropriate handler depending on the object file format.
template <typename AddressesMapBase>
bool DwarfLinkerForBinary::AddressManager<AddressesMapBase>::findValidRelocs(
const object::SectionRef &Section, const object::ObjectFile &Obj,
const DebugMapObject &DMO, std::vector<ValidReloc> &Relocs) {
// Dispatch to the right handler depending on the file type.
if (auto *MachOObj = dyn_cast<object::MachOObjectFile>(&Obj))
findValidRelocsMachO(Section, *MachOObj, DMO, Relocs);
else
Linker.reportWarning(Twine("unsupported object file type: ") +
Obj.getFileName(),
DMO.getObjectFilename());
if (Relocs.empty())
return false;
// Sort the relocations by offset. We will walk the DIEs linearly in
// the file, this allows us to just keep an index in the relocation
// array that we advance during our walk, rather than resorting to
// some associative container. See DwarfLinkerForBinary::NextValidReloc.
llvm::sort(Relocs);
return true;
}
/// Look for relocations in the debug_info and debug_addr section that match
/// entries in the debug map. These relocations will drive the Dwarf link by
/// indicating which DIEs refer to symbols present in the linked binary.
/// \returns whether there are any valid relocations in the debug info.
template <typename AddressesMapBase>
bool DwarfLinkerForBinary::AddressManager<AddressesMapBase>::
findValidRelocsInDebugSections(const object::ObjectFile &Obj,
const DebugMapObject &DMO) {
// Find the debug_info section.
bool FoundValidRelocs = false;
for (const object::SectionRef &Section : Obj.sections()) {
StringRef SectionName;
if (Expected<StringRef> NameOrErr = Section.getName())
SectionName = *NameOrErr;
else
consumeError(NameOrErr.takeError());
SectionName = SectionName.substr(SectionName.find_first_not_of("._"));
if (SectionName == "debug_info")
FoundValidRelocs |=
findValidRelocs(Section, Obj, DMO, ValidDebugInfoRelocs);
if (SectionName == "debug_addr")
FoundValidRelocs |=
findValidRelocs(Section, Obj, DMO, ValidDebugAddrRelocs);
}
return FoundValidRelocs;
}
template <typename AddressesMapBase>
std::vector<
typename DwarfLinkerForBinary::AddressManager<AddressesMapBase>::ValidReloc>
DwarfLinkerForBinary::AddressManager<AddressesMapBase>::getRelocations(
const std::vector<ValidReloc> &Relocs, uint64_t StartPos, uint64_t EndPos) {
std::vector<
DwarfLinkerForBinary::AddressManager<AddressesMapBase>::ValidReloc>
Res;
auto CurReloc = partition_point(Relocs, [StartPos](const ValidReloc &Reloc) {
return Reloc.Offset < StartPos;
});
while (CurReloc != Relocs.end() && CurReloc->Offset >= StartPos &&
CurReloc->Offset < EndPos) {
Res.push_back(*CurReloc);
CurReloc++;
}
return Res;
}
template <typename AddressesMapBase>
void DwarfLinkerForBinary::AddressManager<AddressesMapBase>::printReloc(
const ValidReloc &Reloc) {
const auto &Mapping = Reloc.Mapping->getValue();
const uint64_t ObjectAddress = Mapping.ObjectAddress
? uint64_t(*Mapping.ObjectAddress)
: std::numeric_limits<uint64_t>::max();
outs() << "Found valid debug map entry: " << Reloc.Mapping->getKey() << "\t"
<< format("0x%016" PRIx64 " => 0x%016" PRIx64 "\n", ObjectAddress,
uint64_t(Mapping.BinaryAddress));
}
template <typename AddressesMapBase>
int64_t DwarfLinkerForBinary::AddressManager<AddressesMapBase>::getRelocValue(
const ValidReloc &Reloc) {
int64_t AddrAdjust = relocate(Reloc);
if (Reloc.Mapping->getValue().ObjectAddress)
AddrAdjust -= uint64_t(*Reloc.Mapping->getValue().ObjectAddress);
return AddrAdjust;
}
template <typename AddressesMapBase>
std::optional<int64_t>
DwarfLinkerForBinary::AddressManager<AddressesMapBase>::hasValidRelocationAt(
const std::vector<ValidReloc> &AllRelocs, uint64_t StartOffset,
uint64_t EndOffset) {
std::vector<ValidReloc> Relocs =
getRelocations(AllRelocs, StartOffset, EndOffset);
if (Relocs.size() == 0)
return std::nullopt;
if (Linker.Options.Verbose)
printReloc(Relocs[0]);
return getRelocValue(Relocs[0]);
}
/// Get the starting and ending (exclusive) offset for the
/// attribute with index \p Idx descibed by \p Abbrev. \p Offset is
/// supposed to point to the position of the first attribute described
/// by \p Abbrev.
/// \return [StartOffset, EndOffset) as a pair.
static std::pair<uint64_t, uint64_t>
getAttributeOffsets(const DWARFAbbreviationDeclaration *Abbrev, unsigned Idx,
uint64_t Offset, const DWARFUnit &Unit) {
DataExtractor Data = Unit.getDebugInfoExtractor();
for (unsigned I = 0; I < Idx; ++I)
DWARFFormValue::skipValue(Abbrev->getFormByIndex(I), Data, &Offset,
Unit.getFormParams());
uint64_t End = Offset;
DWARFFormValue::skipValue(Abbrev->getFormByIndex(Idx), Data, &End,
Unit.getFormParams());
return std::make_pair(Offset, End);
}
template <typename AddressesMapBase>
std::optional<int64_t> DwarfLinkerForBinary::AddressManager<AddressesMapBase>::
getExprOpAddressRelocAdjustment(DWARFUnit &U,
const DWARFExpression::Operation &Op,
uint64_t StartOffset, uint64_t EndOffset) {
switch (Op.getCode()) {
default: {
assert(false && "Specified operation does not have address operand");
} break;
case dwarf::DW_OP_const4u:
case dwarf::DW_OP_const8u:
case dwarf::DW_OP_const4s:
case dwarf::DW_OP_const8s:
case dwarf::DW_OP_addr: {
return hasValidRelocationAt(ValidDebugInfoRelocs, StartOffset, EndOffset);
} break;
case dwarf::DW_OP_constx:
case dwarf::DW_OP_addrx: {
return hasValidRelocationAt(ValidDebugAddrRelocs, StartOffset, EndOffset);
} break;
}
return std::nullopt;
}
template <typename AddressesMapBase>
std::optional<int64_t> DwarfLinkerForBinary::AddressManager<
AddressesMapBase>::getSubprogramRelocAdjustment(const DWARFDie &DIE) {
const auto *Abbrev = DIE.getAbbreviationDeclarationPtr();
std::optional<uint32_t> LowPcIdx =
Abbrev->findAttributeIndex(dwarf::DW_AT_low_pc);
if (!LowPcIdx)
return std::nullopt;
dwarf::Form Form = Abbrev->getFormByIndex(*LowPcIdx);
switch (Form) {
case dwarf::DW_FORM_addr: {
uint64_t Offset = DIE.getOffset() + getULEB128Size(Abbrev->getCode());
uint64_t LowPcOffset, LowPcEndOffset;
std::tie(LowPcOffset, LowPcEndOffset) =
getAttributeOffsets(Abbrev, *LowPcIdx, Offset, *DIE.getDwarfUnit());
return hasValidRelocationAt(ValidDebugInfoRelocs, LowPcOffset,
LowPcEndOffset);
}
case dwarf::DW_FORM_addrx:
case dwarf::DW_FORM_addrx1:
case dwarf::DW_FORM_addrx2:
case dwarf::DW_FORM_addrx3:
case dwarf::DW_FORM_addrx4: {
std::optional<DWARFFormValue> AddrValue = DIE.find(dwarf::DW_AT_low_pc);
if (std::optional<uint64_t> AddrOffsetSectionBase =
DIE.getDwarfUnit()->getAddrOffsetSectionBase()) {
uint64_t StartOffset = *AddrOffsetSectionBase + AddrValue->getRawUValue();
uint64_t EndOffset =
StartOffset + DIE.getDwarfUnit()->getAddressByteSize();
return hasValidRelocationAt(ValidDebugAddrRelocs, StartOffset, EndOffset);
}
Linker.reportWarning("no base offset for address table", SrcFileName);
return std::nullopt;
}
default:
return std::nullopt;
}
}
template <typename AddressesMapBase>
uint64_t DwarfLinkerForBinary::AddressManager<AddressesMapBase>::relocate(
const ValidReloc &Reloc) const {
return Reloc.Mapping->getValue().BinaryAddress + Reloc.Addend;
}
/// Apply the valid relocations found by findValidRelocs() to
/// the buffer \p Data, taking into account that Data is at \p BaseOffset
/// in the debug_info section.
///
/// Like for findValidRelocs(), this function must be called with
/// monotonic \p BaseOffset values.
///
/// \returns whether any reloc has been applied.
template <typename AddressesMapBase>
bool DwarfLinkerForBinary::AddressManager<AddressesMapBase>::applyValidRelocs(
MutableArrayRef<char> Data, uint64_t BaseOffset, bool IsLittleEndian) {
std::vector<ValidReloc> Relocs = getRelocations(
ValidDebugInfoRelocs, BaseOffset, BaseOffset + Data.size());
for (const ValidReloc &CurReloc : Relocs) {
assert(CurReloc.Offset - BaseOffset < Data.size());
assert(CurReloc.Offset - BaseOffset + CurReloc.Size <= Data.size());
char Buf[8];
uint64_t Value = relocate(CurReloc);
for (unsigned I = 0; I != CurReloc.Size; ++I) {
unsigned Index = IsLittleEndian ? I : (CurReloc.Size - I - 1);
Buf[I] = uint8_t(Value >> (Index * 8));
}
assert(CurReloc.Size <= sizeof(Buf));
memcpy(&Data[CurReloc.Offset - BaseOffset], Buf, CurReloc.Size);
}
return Relocs.size() > 0;
}
} // namespace dsymutil
} // namespace llvm