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_line.dwo", {MCOFI.getDwarfLineDWOSection(), DW_SECT_LINE}},
143 {"debug_abbrev.dwo", {MCOFI.getDwarfAbbrevDWOSection(), DW_SECT_ABBREV}}};
145 struct UnitIndexEntry {
147 DWARFUnitIndex::Entry::SectionContribution Contributions[8];
150 std::vector<UnitIndexEntry> IndexEntries;
152 StringMap<uint32_t> Strings;
153 uint32_t StringOffset = 0;
155 uint32_t ContributionOffsets[8] = {};
157 for (const auto &Input : Inputs) {
158 auto ErrOrObj = object::ObjectFile::createObjectFile(Input);
160 return ErrOrObj.getError();
162 IndexEntries.emplace_back();
163 UnitIndexEntry &CurEntry = IndexEntries.back();
165 StringRef CurStrSection;
166 StringRef CurStrOffsetSection;
167 StringRef InfoSection;
168 StringRef AbbrevSection;
170 for (const auto &Section : ErrOrObj->getBinary()->sections()) {
172 if (std::error_code Err = Section.getName(Name))
176 KnownSections.find(Name.substr(Name.find_first_not_of("._")));
177 if (SectionPair == KnownSections.end())
181 if (auto Err = Section.getContents(Contents))
184 if (DWARFSectionKind Kind = SectionPair->second.second) {
185 auto Index = Kind - DW_SECT_INFO;
186 CurEntry.Contributions[Index].Offset = ContributionOffsets[Index];
187 ContributionOffsets[Index] +=
188 (CurEntry.Contributions[Index].Length = Contents.size());
190 if (Kind == DW_SECT_INFO) {
191 assert(InfoSection.empty());
192 InfoSection = Contents;
193 } else if (Kind == DW_SECT_ABBREV) {
194 assert(AbbrevSection.empty());
195 AbbrevSection = Contents;
199 MCSection *OutSection = SectionPair->second.first;
200 if (OutSection == StrOffsetSection)
201 CurStrOffsetSection = Contents;
202 else if (OutSection == StrSection)
203 CurStrSection = Contents;
205 Out.SwitchSection(OutSection);
206 Out.EmitBytes(Contents);
210 assert(!AbbrevSection.empty());
211 assert(!InfoSection.empty());
212 CurEntry.Signature = getCUSignature(AbbrevSection, InfoSection);
214 if (auto Err = writeStringsAndOffsets(Out, Strings, StringOffset,
215 StrSection, StrOffsetSection,
216 CurStrSection, CurStrOffsetSection))
220 unsigned Columns = 0;
221 for (auto &C : ContributionOffsets)
225 Out.SwitchSection(MCOFI.getDwarfCUIndexSection());
226 Out.EmitIntValue(2, 4); // Version
227 Out.EmitIntValue(Columns, 4); // Columns
228 Out.EmitIntValue(IndexEntries.size(), 4); // Num Units
229 // FIXME: This is not the right number of buckets for a real hash.
230 Out.EmitIntValue(IndexEntries.size(), 4); // Num Buckets
232 // Write the signatures.
233 for (const auto &E : IndexEntries)
234 Out.EmitIntValue(E.Signature, 8);
236 // Write the indexes.
237 for (size_t i = 0; i != IndexEntries.size(); ++i)
238 Out.EmitIntValue(i + 1, 4);
240 // Write the column headers (which sections will appear in the table)
241 for (size_t i = 0; i != array_lengthof(ContributionOffsets); ++i)
242 if (ContributionOffsets[i])
243 Out.EmitIntValue(i + DW_SECT_INFO, 4);
245 // Write the offsets.
246 for (const auto &E : IndexEntries)
247 for (size_t i = 0; i != array_lengthof(E.Contributions); ++i)
248 if (ContributionOffsets[i])
249 Out.EmitIntValue(E.Contributions[i].Offset, 4);
251 // Write the lengths.
252 for (const auto &E : IndexEntries)
253 for (size_t i = 0; i != array_lengthof(E.Contributions); ++i)
254 if (ContributionOffsets[i])
255 Out.EmitIntValue(E.Contributions[i].Length, 4);
257 return std::error_code();
260 int main(int argc, char** argv) {
262 ParseCommandLineOptions(argc, argv, "merge split dwarf (.dwo) files");
264 llvm::InitializeAllTargetInfos();
265 llvm::InitializeAllTargetMCs();
266 llvm::InitializeAllTargets();
267 llvm::InitializeAllAsmPrinters();
269 std::string ErrorStr;
270 StringRef Context = "dwarf streamer init";
272 Triple TheTriple("x86_64-linux-gnu");
275 const Target *TheTarget =
276 TargetRegistry::lookupTarget("", TheTriple, ErrorStr);
278 return error(ErrorStr, Context);
279 std::string TripleName = TheTriple.getTriple();
281 // Create all the MC Objects.
282 std::unique_ptr<MCRegisterInfo> MRI(TheTarget->createMCRegInfo(TripleName));
284 return error(Twine("no register info for target ") + TripleName, Context);
286 std::unique_ptr<MCAsmInfo> MAI(TheTarget->createMCAsmInfo(*MRI, TripleName));
288 return error("no asm info for target " + TripleName, Context);
290 MCObjectFileInfo MOFI;
291 MCContext MC(MAI.get(), MRI.get(), &MOFI);
292 MOFI.InitMCObjectFileInfo(TheTriple, Reloc::Default, CodeModel::Default,
295 auto MAB = TheTarget->createMCAsmBackend(*MRI, TripleName, "");
297 return error("no asm backend for target " + TripleName, Context);
299 std::unique_ptr<MCInstrInfo> MII(TheTarget->createMCInstrInfo());
301 return error("no instr info info for target " + TripleName, Context);
303 std::unique_ptr<MCSubtargetInfo> MSTI(
304 TheTarget->createMCSubtargetInfo(TripleName, "", ""));
306 return error("no subtarget info for target " + TripleName, Context);
308 MCCodeEmitter *MCE = TheTarget->createMCCodeEmitter(*MII, *MRI, MC);
310 return error("no code emitter for target " + TripleName, Context);
312 // Create the output file.
314 raw_fd_ostream OutFile(OutputFilename, EC, sys::fs::F_None);
316 return error(Twine(OutputFilename) + ": " + EC.message(), Context);
318 std::unique_ptr<MCStreamer> MS(TheTarget->createMCObjectStreamer(
319 TheTriple, MC, *MAB, OutFile, MCE, *MSTI, false,
320 /*DWARFMustBeAtTheEnd*/ false));
322 return error("no object streamer for target " + TripleName, Context);
324 if (auto Err = write(*MS, InputFiles))
325 return error(Err.message(), "Writing DWP file");