1 #include "llvm/ADT/STLExtras.h"
2 #include "llvm/ADT/StringSet.h"
3 #include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
4 #include "llvm/CodeGen/AsmPrinter.h"
5 #include "llvm/MC/MCAsmInfo.h"
6 #include "llvm/MC/MCContext.h"
7 #include "llvm/MC/MCInstrInfo.h"
8 #include "llvm/MC/MCObjectFileInfo.h"
9 #include "llvm/MC/MCRegisterInfo.h"
10 #include "llvm/MC/MCSectionELF.h"
11 #include "llvm/MC/MCStreamer.h"
12 #include "llvm/Object/ObjectFile.h"
13 #include "llvm/Support/DataExtractor.h"
14 #include "llvm/Support/Options.h"
15 #include "llvm/Support/FileSystem.h"
16 #include "llvm/Support/MemoryBuffer.h"
17 #include "llvm/Support/TargetRegistry.h"
18 #include "llvm/Support/raw_ostream.h"
19 #include "llvm/Target/TargetMachine.h"
20 #include "llvm/Support/TargetSelect.h"
21 #include "llvm/DebugInfo/DWARF/DWARFUnitIndex.h"
24 #include <unordered_set>
27 using namespace llvm::object;
30 OptionCategory DwpCategory("Specific Options");
31 static list<std::string> InputFiles(Positional, OneOrMore,
32 desc("<input files>"), cat(DwpCategory));
34 static opt<std::string> OutputFilename(Required, "o", desc("Specify the output file."),
35 value_desc("filename"), cat(DwpCategory));
37 static int error(const Twine &Error, const Twine &Context) {
38 errs() << Twine("while processing ") + Context + ":\n";
39 errs() << Twine("error: ") + Error + "\n";
43 static std::error_code
44 writeStringsAndOffsets(MCStreamer &Out, StringMap<uint32_t> &Strings,
45 uint32_t &StringOffset, MCSection *StrSection,
46 MCSection *StrOffsetSection, StringRef CurStrSection,
47 StringRef CurStrOffsetSection) {
48 // Could possibly produce an error or warning if one of these was non-null but
49 // the other was null.
50 if (CurStrSection.empty() || CurStrOffsetSection.empty())
51 return std::error_code();
53 DenseMap<uint32_t, uint32_t> OffsetRemapping;
55 DataExtractor Data(CurStrSection, true, 0);
56 uint32_t LocalOffset = 0;
57 uint32_t PrevOffset = 0;
58 while (const char *s = Data.getCStr(&LocalOffset)) {
59 StringRef Str(s, LocalOffset - PrevOffset - 1);
60 auto Pair = Strings.insert(std::make_pair(Str, StringOffset));
62 Out.SwitchSection(StrSection);
64 StringRef(Pair.first->getKeyData(), Pair.first->getKeyLength() + 1));
65 StringOffset += Str.size() + 1;
67 OffsetRemapping[PrevOffset] = Pair.first->second;
68 PrevOffset = LocalOffset;
71 Data = DataExtractor(CurStrOffsetSection, true, 0);
73 Out.SwitchSection(StrOffsetSection);
76 uint64_t Size = CurStrOffsetSection.size();
77 while (Offset < Size) {
78 auto OldOffset = Data.getU32(&Offset);
79 auto NewOffset = OffsetRemapping[OldOffset];
80 Out.EmitIntValue(NewOffset, 4);
83 return std::error_code();
86 static uint32_t getCUAbbrev(StringRef Abbrev, uint64_t AbbrCode) {
89 DataExtractor AbbrevData(Abbrev, true, 0);
90 while ((CurCode = AbbrevData.getULEB128(&Offset)) != AbbrCode) {
92 AbbrevData.getULEB128(&Offset);
94 AbbrevData.getU8(&Offset);
96 while (AbbrevData.getULEB128(&Offset) | AbbrevData.getULEB128(&Offset))
102 static uint64_t getCUSignature(StringRef Abbrev, StringRef Info) {
104 DataExtractor InfoData(Info, true, 0);
105 InfoData.getU32(&Offset); // Length
106 uint16_t Version = InfoData.getU16(&Offset);
107 InfoData.getU32(&Offset); // Abbrev offset (should be zero)
108 uint8_t AddrSize = InfoData.getU8(&Offset);
110 uint32_t AbbrCode = InfoData.getULEB128(&Offset);
112 DataExtractor AbbrevData(Abbrev, true, 0);
113 uint32_t AbbrevOffset = getCUAbbrev(Abbrev, AbbrCode);
114 uint64_t Tag = AbbrevData.getULEB128(&AbbrevOffset);
116 // FIXME: Real error handling
117 assert(Tag == dwarf::DW_TAG_compile_unit);
119 AbbrevData.getU8(&AbbrevOffset);
122 while ((Name = AbbrevData.getULEB128(&AbbrevOffset)) |
123 (Form = AbbrevData.getULEB128(&AbbrevOffset)) &&
124 Name != dwarf::DW_AT_GNU_dwo_id) {
125 DWARFFormValue::skipValue(Form, InfoData, &Offset, Version, AddrSize);
127 // FIXME: Real error handling
128 assert(Name == dwarf::DW_AT_GNU_dwo_id);
129 return InfoData.getU64(&Offset);
132 static std::error_code write(MCStreamer &Out, ArrayRef<std::string> Inputs) {
133 const auto &MCOFI = *Out.getContext().getObjectFileInfo();
134 MCSection *const StrSection = MCOFI.getDwarfStrDWOSection();
135 MCSection *const StrOffsetSection = MCOFI.getDwarfStrOffDWOSection();
136 const StringMap<std::pair<MCSection *, DWARFSectionKind>> KnownSections = {
137 {"debug_info.dwo", {MCOFI.getDwarfInfoDWOSection(), DW_SECT_INFO}},
138 {"debug_types.dwo", {MCOFI.getDwarfTypesDWOSection(), DW_SECT_TYPES}},
139 {"debug_str_offsets.dwo", {StrOffsetSection, DW_SECT_STR_OFFSETS}},
140 {"debug_str.dwo", {StrSection, static_cast<DWARFSectionKind>(0)}},
141 {"debug_loc.dwo", {MCOFI.getDwarfLocDWOSection(), DW_SECT_LOC}},
142 {"debug_abbrev.dwo", {MCOFI.getDwarfAbbrevDWOSection(), DW_SECT_ABBREV}}};
144 struct UnitIndexEntry {
146 DWARFUnitIndex::Entry::SectionContribution Contributions[8];
149 std::vector<UnitIndexEntry> IndexEntries;
151 StringMap<uint32_t> Strings;
152 uint32_t StringOffset = 0;
154 uint32_t ContributionOffsets[8] = {};
156 for (const auto &Input : Inputs) {
157 auto ErrOrObj = object::ObjectFile::createObjectFile(Input);
159 return ErrOrObj.getError();
161 IndexEntries.emplace_back();
162 UnitIndexEntry &CurEntry = IndexEntries.back();
164 StringRef CurStrSection;
165 StringRef CurStrOffsetSection;
166 StringRef InfoSection;
167 StringRef AbbrevSection;
169 for (const auto &Section : ErrOrObj->getBinary()->sections()) {
171 if (std::error_code Err = Section.getName(Name))
175 KnownSections.find(Name.substr(Name.find_first_not_of("._")));
176 if (SectionPair == KnownSections.end())
180 if (auto Err = Section.getContents(Contents))
183 if (DWARFSectionKind Kind = SectionPair->second.second) {
184 auto Index = Kind - DW_SECT_INFO;
185 CurEntry.Contributions[Index].Offset = ContributionOffsets[Index];
186 ContributionOffsets[Index] +=
187 (CurEntry.Contributions[Index].Length = Contents.size());
189 if (Kind == DW_SECT_INFO) {
190 assert(InfoSection.empty());
191 InfoSection = Contents;
192 } else if (Kind == DW_SECT_ABBREV) {
193 assert(AbbrevSection.empty());
194 AbbrevSection = Contents;
198 MCSection *OutSection = SectionPair->second.first;
199 if (OutSection == StrOffsetSection)
200 CurStrOffsetSection = Contents;
201 else if (OutSection == StrSection)
202 CurStrSection = Contents;
204 Out.SwitchSection(OutSection);
205 Out.EmitBytes(Contents);
209 assert(!AbbrevSection.empty());
210 assert(!InfoSection.empty());
211 CurEntry.Signature = getCUSignature(AbbrevSection, InfoSection);
213 if (auto Err = writeStringsAndOffsets(Out, Strings, StringOffset,
214 StrSection, StrOffsetSection,
215 CurStrSection, CurStrOffsetSection))
219 unsigned Columns = 0;
220 for (auto &C : ContributionOffsets)
224 Out.SwitchSection(MCOFI.getDwarfCUIndexSection());
225 Out.EmitIntValue(2, 4); // Version
226 Out.EmitIntValue(Columns, 4); // Columns
227 Out.EmitIntValue(IndexEntries.size(), 4); // Num Units
228 // FIXME: This is not the right number of buckets for a real hash.
229 Out.EmitIntValue(IndexEntries.size(), 4); // Num Buckets
231 // Write the signatures.
232 for (const auto &E : IndexEntries)
233 Out.EmitIntValue(E.Signature, 8);
235 // Write the indexes.
236 for (size_t i = 0; i != IndexEntries.size(); ++i)
237 Out.EmitIntValue(i + 1, 4);
239 // Write the column headers (which sections will appear in the table)
240 for (size_t i = 0; i != array_lengthof(ContributionOffsets); ++i)
241 if (ContributionOffsets[i])
242 Out.EmitIntValue(i + DW_SECT_INFO, 4);
244 // Write the offsets.
245 for (const auto &E : IndexEntries)
246 for (size_t i = 0; i != array_lengthof(E.Contributions); ++i)
247 if (ContributionOffsets[i])
248 Out.EmitIntValue(E.Contributions[i].Offset, 4);
250 // Write the lengths.
251 for (const auto &E : IndexEntries)
252 for (size_t i = 0; i != array_lengthof(E.Contributions); ++i)
253 if (ContributionOffsets[i])
254 Out.EmitIntValue(E.Contributions[i].Length, 4);
256 return std::error_code();
259 int main(int argc, char** argv) {
261 ParseCommandLineOptions(argc, argv, "merge split dwarf (.dwo) files");
263 llvm::InitializeAllTargetInfos();
264 llvm::InitializeAllTargetMCs();
265 llvm::InitializeAllTargets();
266 llvm::InitializeAllAsmPrinters();
268 std::string ErrorStr;
269 StringRef Context = "dwarf streamer init";
271 Triple TheTriple("x86_64-linux-gnu");
274 const Target *TheTarget =
275 TargetRegistry::lookupTarget("", TheTriple, ErrorStr);
277 return error(ErrorStr, Context);
278 std::string TripleName = TheTriple.getTriple();
280 // Create all the MC Objects.
281 std::unique_ptr<MCRegisterInfo> MRI(TheTarget->createMCRegInfo(TripleName));
283 return error(Twine("no register info for target ") + TripleName, Context);
285 std::unique_ptr<MCAsmInfo> MAI(TheTarget->createMCAsmInfo(*MRI, TripleName));
287 return error("no asm info for target " + TripleName, Context);
289 MCObjectFileInfo MOFI;
290 MCContext MC(MAI.get(), MRI.get(), &MOFI);
291 MOFI.InitMCObjectFileInfo(TheTriple, Reloc::Default, CodeModel::Default,
294 auto MAB = TheTarget->createMCAsmBackend(*MRI, TripleName, "");
296 return error("no asm backend for target " + TripleName, Context);
298 std::unique_ptr<MCInstrInfo> MII(TheTarget->createMCInstrInfo());
300 return error("no instr info info for target " + TripleName, Context);
302 std::unique_ptr<MCSubtargetInfo> MSTI(
303 TheTarget->createMCSubtargetInfo(TripleName, "", ""));
305 return error("no subtarget info for target " + TripleName, Context);
307 MCCodeEmitter *MCE = TheTarget->createMCCodeEmitter(*MII, *MRI, MC);
309 return error("no code emitter for target " + TripleName, Context);
311 // Create the output file.
313 raw_fd_ostream OutFile(OutputFilename, EC, sys::fs::F_None);
315 return error(Twine(OutputFilename) + ": " + EC.message(), Context);
317 std::unique_ptr<MCStreamer> MS(TheTarget->createMCObjectStreamer(
318 TheTriple, MC, *MAB, OutFile, MCE, *MSTI, false,
319 /*DWARFMustBeAtTheEnd*/ false));
321 return error("no object streamer for target " + TripleName, Context);
323 if (auto Err = write(*MS, InputFiles))
324 return error(Err.message(), "Writing DWP file");