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-rw-r--r--tools/llvm-dwp/llvm-dwp.cpp420
1 files changed, 420 insertions, 0 deletions
diff --git a/tools/llvm-dwp/llvm-dwp.cpp b/tools/llvm-dwp/llvm-dwp.cpp
new file mode 100644
index 000000000000..570854b849c1
--- /dev/null
+++ b/tools/llvm-dwp/llvm-dwp.cpp
@@ -0,0 +1,420 @@
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/StringSet.h"
+#include "llvm/CodeGen/AsmPrinter.h"
+#include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
+#include "llvm/DebugInfo/DWARF/DWARFUnitIndex.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCInstrInfo.h"
+#include "llvm/MC/MCObjectFileInfo.h"
+#include "llvm/MC/MCRegisterInfo.h"
+#include "llvm/MC/MCSectionELF.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCTargetOptionsCommandFlags.h"
+#include "llvm/Object/ObjectFile.h"
+#include "llvm/Support/DataExtractor.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/MathExtras.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/Options.h"
+#include "llvm/Support/TargetRegistry.h"
+#include "llvm/Support/TargetSelect.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Target/TargetMachine.h"
+#include <list>
+#include <memory>
+#include <unordered_set>
+
+using namespace llvm;
+using namespace llvm::object;
+using namespace cl;
+
+OptionCategory DwpCategory("Specific Options");
+static list<std::string> InputFiles(Positional, OneOrMore,
+ desc("<input files>"), cat(DwpCategory));
+
+static opt<std::string> OutputFilename(Required, "o",
+ desc("Specify the output file."),
+ value_desc("filename"),
+ cat(DwpCategory));
+
+static int error(const Twine &Error, const Twine &Context) {
+ errs() << Twine("while processing ") + Context + ":\n";
+ errs() << Twine("error: ") + Error + "\n";
+ return 1;
+}
+
+static std::error_code
+writeStringsAndOffsets(MCStreamer &Out, StringMap<uint32_t> &Strings,
+ uint32_t &StringOffset, MCSection *StrSection,
+ MCSection *StrOffsetSection, StringRef CurStrSection,
+ StringRef CurStrOffsetSection) {
+ // Could possibly produce an error or warning if one of these was non-null but
+ // the other was null.
+ if (CurStrSection.empty() || CurStrOffsetSection.empty())
+ return std::error_code();
+
+ DenseMap<uint32_t, uint32_t> OffsetRemapping;
+
+ DataExtractor Data(CurStrSection, true, 0);
+ uint32_t LocalOffset = 0;
+ uint32_t PrevOffset = 0;
+ while (const char *s = Data.getCStr(&LocalOffset)) {
+ StringRef Str(s, LocalOffset - PrevOffset - 1);
+ auto Pair = Strings.insert(std::make_pair(Str, StringOffset));
+ if (Pair.second) {
+ Out.SwitchSection(StrSection);
+ Out.EmitBytes(
+ StringRef(Pair.first->getKeyData(), Pair.first->getKeyLength() + 1));
+ StringOffset += Str.size() + 1;
+ }
+ OffsetRemapping[PrevOffset] = Pair.first->second;
+ PrevOffset = LocalOffset;
+ }
+
+ Data = DataExtractor(CurStrOffsetSection, true, 0);
+
+ Out.SwitchSection(StrOffsetSection);
+
+ uint32_t Offset = 0;
+ uint64_t Size = CurStrOffsetSection.size();
+ while (Offset < Size) {
+ auto OldOffset = Data.getU32(&Offset);
+ auto NewOffset = OffsetRemapping[OldOffset];
+ Out.EmitIntValue(NewOffset, 4);
+ }
+
+ return std::error_code();
+}
+
+static uint32_t getCUAbbrev(StringRef Abbrev, uint64_t AbbrCode) {
+ uint64_t CurCode;
+ uint32_t Offset = 0;
+ DataExtractor AbbrevData(Abbrev, true, 0);
+ while ((CurCode = AbbrevData.getULEB128(&Offset)) != AbbrCode) {
+ // Tag
+ AbbrevData.getULEB128(&Offset);
+ // DW_CHILDREN
+ AbbrevData.getU8(&Offset);
+ // Attributes
+ while (AbbrevData.getULEB128(&Offset) | AbbrevData.getULEB128(&Offset))
+ ;
+ }
+ return Offset;
+}
+
+static uint64_t getCUSignature(StringRef Abbrev, StringRef Info) {
+ uint32_t Offset = 0;
+ DataExtractor InfoData(Info, true, 0);
+ InfoData.getU32(&Offset); // Length
+ uint16_t Version = InfoData.getU16(&Offset);
+ InfoData.getU32(&Offset); // Abbrev offset (should be zero)
+ uint8_t AddrSize = InfoData.getU8(&Offset);
+
+ uint32_t AbbrCode = InfoData.getULEB128(&Offset);
+
+ DataExtractor AbbrevData(Abbrev, true, 0);
+ uint32_t AbbrevOffset = getCUAbbrev(Abbrev, AbbrCode);
+ uint64_t Tag = AbbrevData.getULEB128(&AbbrevOffset);
+ (void)Tag;
+ // FIXME: Real error handling
+ assert(Tag == dwarf::DW_TAG_compile_unit);
+ // DW_CHILDREN
+ AbbrevData.getU8(&AbbrevOffset);
+ uint32_t Name;
+ uint32_t Form;
+ while ((Name = AbbrevData.getULEB128(&AbbrevOffset)) |
+ (Form = AbbrevData.getULEB128(&AbbrevOffset)) &&
+ Name != dwarf::DW_AT_GNU_dwo_id) {
+ DWARFFormValue::skipValue(Form, InfoData, &Offset, Version, AddrSize);
+ }
+ // FIXME: Real error handling
+ assert(Name == dwarf::DW_AT_GNU_dwo_id);
+ return InfoData.getU64(&Offset);
+}
+
+struct UnitIndexEntry {
+ uint64_t Signature;
+ DWARFUnitIndex::Entry::SectionContribution Contributions[8];
+};
+
+static void addAllTypes(MCStreamer &Out,
+ std::vector<UnitIndexEntry> &TypeIndexEntries,
+ MCSection *OutputTypes, StringRef Types,
+ const UnitIndexEntry &CUEntry, uint32_t &TypesOffset) {
+ if (Types.empty())
+ return;
+
+ Out.SwitchSection(OutputTypes);
+ uint32_t Offset = 0;
+ DataExtractor Data(Types, true, 0);
+ while (Data.isValidOffset(Offset)) {
+ UnitIndexEntry Entry = CUEntry;
+ // Zero out the debug_info contribution
+ Entry.Contributions[0] = {};
+ auto &C = Entry.Contributions[DW_SECT_TYPES - DW_SECT_INFO];
+ C.Offset = TypesOffset;
+ auto PrevOffset = Offset;
+ // Length of the unit, including the 4 byte length field.
+ C.Length = Data.getU32(&Offset) + 4;
+
+ Data.getU16(&Offset); // Version
+ Data.getU32(&Offset); // Abbrev offset
+ Data.getU8(&Offset); // Address size
+ Entry.Signature = Data.getU64(&Offset);
+ Offset = PrevOffset + C.Length;
+
+ if (any_of(TypeIndexEntries, [&](const UnitIndexEntry &E) {
+ return E.Signature == Entry.Signature;
+ }))
+ continue;
+
+ Out.EmitBytes(Types.substr(PrevOffset, C.Length));
+ TypesOffset += C.Length;
+
+ TypeIndexEntries.push_back(Entry);
+ }
+}
+
+static void
+writeIndexTable(MCStreamer &Out, ArrayRef<unsigned> ContributionOffsets,
+ ArrayRef<UnitIndexEntry> IndexEntries,
+ uint32_t DWARFUnitIndex::Entry::SectionContribution::*Field) {
+ for (const auto &E : IndexEntries)
+ for (size_t i = 0; i != array_lengthof(E.Contributions); ++i)
+ if (ContributionOffsets[i])
+ Out.EmitIntValue(E.Contributions[i].*Field, 4);
+}
+
+static void writeIndex(MCStreamer &Out, MCSection *Section,
+ ArrayRef<unsigned> ContributionOffsets,
+ ArrayRef<UnitIndexEntry> IndexEntries) {
+ unsigned Columns = 0;
+ for (auto &C : ContributionOffsets)
+ if (C)
+ ++Columns;
+
+ std::vector<unsigned> Buckets(NextPowerOf2(3 * IndexEntries.size() / 2));
+ uint64_t Mask = Buckets.size() - 1;
+ for (size_t i = 0; i != IndexEntries.size(); ++i) {
+ auto S = IndexEntries[i].Signature;
+ auto H = S & Mask;
+ while (Buckets[H]) {
+ assert(S != IndexEntries[Buckets[H] - 1].Signature &&
+ "Duplicate type unit");
+ H += ((S >> 32) & Mask) | 1;
+ }
+ Buckets[H] = i + 1;
+ }
+
+ Out.SwitchSection(Section);
+ Out.EmitIntValue(2, 4); // Version
+ Out.EmitIntValue(Columns, 4); // Columns
+ Out.EmitIntValue(IndexEntries.size(), 4); // Num Units
+ Out.EmitIntValue(Buckets.size(), 4); // Num Buckets
+
+ // Write the signatures.
+ for (const auto &I : Buckets)
+ Out.EmitIntValue(I ? IndexEntries[I - 1].Signature : 0, 8);
+
+ // Write the indexes.
+ for (const auto &I : Buckets)
+ Out.EmitIntValue(I, 4);
+
+ // Write the column headers (which sections will appear in the table)
+ for (size_t i = 0; i != ContributionOffsets.size(); ++i)
+ if (ContributionOffsets[i])
+ Out.EmitIntValue(i + DW_SECT_INFO, 4);
+
+ // Write the offsets.
+ writeIndexTable(Out, ContributionOffsets, IndexEntries,
+ &DWARFUnitIndex::Entry::SectionContribution::Offset);
+
+ // Write the lengths.
+ writeIndexTable(Out, ContributionOffsets, IndexEntries,
+ &DWARFUnitIndex::Entry::SectionContribution::Length);
+}
+static std::error_code write(MCStreamer &Out, ArrayRef<std::string> Inputs) {
+ const auto &MCOFI = *Out.getContext().getObjectFileInfo();
+ MCSection *const StrSection = MCOFI.getDwarfStrDWOSection();
+ MCSection *const StrOffsetSection = MCOFI.getDwarfStrOffDWOSection();
+ MCSection *const TypesSection = MCOFI.getDwarfTypesDWOSection();
+ const StringMap<std::pair<MCSection *, DWARFSectionKind>> KnownSections = {
+ {"debug_info.dwo", {MCOFI.getDwarfInfoDWOSection(), DW_SECT_INFO}},
+ {"debug_types.dwo", {MCOFI.getDwarfTypesDWOSection(), DW_SECT_TYPES}},
+ {"debug_str_offsets.dwo", {StrOffsetSection, DW_SECT_STR_OFFSETS}},
+ {"debug_str.dwo", {StrSection, static_cast<DWARFSectionKind>(0)}},
+ {"debug_loc.dwo", {MCOFI.getDwarfLocDWOSection(), DW_SECT_LOC}},
+ {"debug_line.dwo", {MCOFI.getDwarfLineDWOSection(), DW_SECT_LINE}},
+ {"debug_abbrev.dwo", {MCOFI.getDwarfAbbrevDWOSection(), DW_SECT_ABBREV}}};
+
+ std::vector<UnitIndexEntry> IndexEntries;
+ std::vector<UnitIndexEntry> TypeIndexEntries;
+
+ StringMap<uint32_t> Strings;
+ uint32_t StringOffset = 0;
+
+ uint32_t ContributionOffsets[8] = {};
+
+ for (const auto &Input : Inputs) {
+ auto ErrOrObj = object::ObjectFile::createObjectFile(Input);
+ if (!ErrOrObj)
+ return ErrOrObj.getError();
+
+ IndexEntries.emplace_back();
+ UnitIndexEntry &CurEntry = IndexEntries.back();
+
+ StringRef CurStrSection;
+ StringRef CurStrOffsetSection;
+ StringRef CurTypesSection;
+ StringRef InfoSection;
+ StringRef AbbrevSection;
+
+ for (const auto &Section : ErrOrObj->getBinary()->sections()) {
+ StringRef Name;
+ if (std::error_code Err = Section.getName(Name))
+ return Err;
+
+ auto SectionPair =
+ KnownSections.find(Name.substr(Name.find_first_not_of("._")));
+ if (SectionPair == KnownSections.end())
+ continue;
+
+ StringRef Contents;
+ if (auto Err = Section.getContents(Contents))
+ return Err;
+
+ if (DWARFSectionKind Kind = SectionPair->second.second) {
+ auto Index = Kind - DW_SECT_INFO;
+ if (Kind != DW_SECT_TYPES) {
+ CurEntry.Contributions[Index].Offset = ContributionOffsets[Index];
+ ContributionOffsets[Index] +=
+ (CurEntry.Contributions[Index].Length = Contents.size());
+ }
+
+ switch (Kind) {
+ case DW_SECT_INFO:
+ InfoSection = Contents;
+ break;
+ case DW_SECT_ABBREV:
+ AbbrevSection = Contents;
+ break;
+ default:
+ break;
+ }
+ }
+
+ MCSection *OutSection = SectionPair->second.first;
+ if (OutSection == StrOffsetSection)
+ CurStrOffsetSection = Contents;
+ else if (OutSection == StrSection)
+ CurStrSection = Contents;
+ else if (OutSection == TypesSection)
+ CurTypesSection = Contents;
+ else {
+ Out.SwitchSection(OutSection);
+ Out.EmitBytes(Contents);
+ }
+ }
+
+ assert(!AbbrevSection.empty());
+ assert(!InfoSection.empty());
+ CurEntry.Signature = getCUSignature(AbbrevSection, InfoSection);
+ addAllTypes(Out, TypeIndexEntries, TypesSection, CurTypesSection, CurEntry,
+ ContributionOffsets[DW_SECT_TYPES - DW_SECT_INFO]);
+
+ if (auto Err = writeStringsAndOffsets(Out, Strings, StringOffset,
+ StrSection, StrOffsetSection,
+ CurStrSection, CurStrOffsetSection))
+ return Err;
+ }
+
+ if (!TypeIndexEntries.empty()) {
+ // Lie about there being no info contributions so the TU index only includes
+ // the type unit contribution
+ ContributionOffsets[0] = 0;
+ writeIndex(Out, MCOFI.getDwarfTUIndexSection(), ContributionOffsets,
+ TypeIndexEntries);
+ }
+
+ // Lie about the type contribution
+ ContributionOffsets[DW_SECT_TYPES - DW_SECT_INFO] = 0;
+ // Unlie about the info contribution
+ ContributionOffsets[0] = 1;
+
+ writeIndex(Out, MCOFI.getDwarfCUIndexSection(), ContributionOffsets,
+ IndexEntries);
+
+ return std::error_code();
+}
+
+int main(int argc, char **argv) {
+
+ ParseCommandLineOptions(argc, argv, "merge split dwarf (.dwo) files");
+
+ llvm::InitializeAllTargetInfos();
+ llvm::InitializeAllTargetMCs();
+ llvm::InitializeAllTargets();
+ llvm::InitializeAllAsmPrinters();
+
+ std::string ErrorStr;
+ StringRef Context = "dwarf streamer init";
+
+ Triple TheTriple("x86_64-linux-gnu");
+
+ // Get the target.
+ const Target *TheTarget =
+ TargetRegistry::lookupTarget("", TheTriple, ErrorStr);
+ if (!TheTarget)
+ return error(ErrorStr, Context);
+ std::string TripleName = TheTriple.getTriple();
+
+ // Create all the MC Objects.
+ std::unique_ptr<MCRegisterInfo> MRI(TheTarget->createMCRegInfo(TripleName));
+ if (!MRI)
+ return error(Twine("no register info for target ") + TripleName, Context);
+
+ std::unique_ptr<MCAsmInfo> MAI(TheTarget->createMCAsmInfo(*MRI, TripleName));
+ if (!MAI)
+ return error("no asm info for target " + TripleName, Context);
+
+ MCObjectFileInfo MOFI;
+ MCContext MC(MAI.get(), MRI.get(), &MOFI);
+ MOFI.InitMCObjectFileInfo(TheTriple, Reloc::Default, CodeModel::Default, MC);
+
+ auto MAB = TheTarget->createMCAsmBackend(*MRI, TripleName, "");
+ if (!MAB)
+ return error("no asm backend for target " + TripleName, Context);
+
+ std::unique_ptr<MCInstrInfo> MII(TheTarget->createMCInstrInfo());
+ if (!MII)
+ return error("no instr info info for target " + TripleName, Context);
+
+ std::unique_ptr<MCSubtargetInfo> MSTI(
+ TheTarget->createMCSubtargetInfo(TripleName, "", ""));
+ if (!MSTI)
+ return error("no subtarget info for target " + TripleName, Context);
+
+ MCCodeEmitter *MCE = TheTarget->createMCCodeEmitter(*MII, *MRI, MC);
+ if (!MCE)
+ return error("no code emitter for target " + TripleName, Context);
+
+ // Create the output file.
+ std::error_code EC;
+ raw_fd_ostream OutFile(OutputFilename, EC, sys::fs::F_None);
+ if (EC)
+ return error(Twine(OutputFilename) + ": " + EC.message(), Context);
+
+ MCTargetOptions MCOptions = InitMCTargetOptionsFromFlags();
+ std::unique_ptr<MCStreamer> MS(TheTarget->createMCObjectStreamer(
+ TheTriple, MC, *MAB, OutFile, MCE, *MSTI, MCOptions.MCRelaxAll,
+ MCOptions.MCIncrementalLinkerCompatible,
+ /*DWARFMustBeAtTheEnd*/ false));
+ if (!MS)
+ return error("no object streamer for target " + TripleName, Context);
+
+ if (auto Err = write(*MS, InputFiles))
+ return error(Err.message(), "Writing DWP file");
+
+ MS->Finish();
+}
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