1 //===-- llvm-dwp.cpp - Split DWARF merging tool for llvm ------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // A utility for merging DWARF 5 Split DWARF .dwo files into .dwp (DWARF
11 // package files).
12 //
13 //===----------------------------------------------------------------------===//
14 #include "DWPError.h"
15 #include "DWPStringPool.h"
16 #include "llvm/ADT/MapVector.h"
17 #include "llvm/ADT/STLExtras.h"
18 #include "llvm/ADT/StringSet.h"
19 #include "llvm/CodeGen/AsmPrinter.h"
20 #include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
21 #include "llvm/DebugInfo/DWARF/DWARFUnitIndex.h"
22 #include "llvm/MC/MCAsmInfo.h"
23 #include "llvm/MC/MCContext.h"
24 #include "llvm/MC/MCInstrInfo.h"
25 #include "llvm/MC/MCObjectFileInfo.h"
26 #include "llvm/MC/MCRegisterInfo.h"
27 #include "llvm/MC/MCSectionELF.h"
28 #include "llvm/MC/MCStreamer.h"
29 #include "llvm/MC/MCTargetOptionsCommandFlags.h"
30 #include "llvm/Object/ObjectFile.h"
31 #include "llvm/Support/Compression.h"
32 #include "llvm/Support/DataExtractor.h"
33 #include "llvm/Support/Error.h"
34 #include "llvm/Support/FileSystem.h"
35 #include "llvm/Support/MathExtras.h"
36 #include "llvm/Support/MemoryBuffer.h"
37 #include "llvm/Support/Options.h"
38 #include "llvm/Support/TargetRegistry.h"
39 #include "llvm/Support/TargetSelect.h"
40 #include "llvm/Support/raw_ostream.h"
41 #include "llvm/Target/TargetMachine.h"
42 #include <deque>
43 #include <iostream>
44 #include <memory>
45
46 using namespace llvm;
47 using namespace llvm::object;
48 using namespace cl;
49
50 OptionCategory DwpCategory("Specific Options");
51 static list<std::string> InputFiles(Positional, OneOrMore,
52 desc("<input files>"), cat(DwpCategory));
53
54 static opt<std::string> OutputFilename(Required, "o",
55 desc("Specify the output file."),
56 value_desc("filename"),
57 cat(DwpCategory));
58
writeStringsAndOffsets(MCStreamer & Out,DWPStringPool & Strings,MCSection * StrOffsetSection,StringRef CurStrSection,StringRef CurStrOffsetSection)59 static void writeStringsAndOffsets(MCStreamer &Out, DWPStringPool &Strings,
60 MCSection *StrOffsetSection,
61 StringRef CurStrSection,
62 StringRef CurStrOffsetSection) {
63 // Could possibly produce an error or warning if one of these was non-null but
64 // the other was null.
65 if (CurStrSection.empty() || CurStrOffsetSection.empty())
66 return;
67
68 DenseMap<uint32_t, uint32_t> OffsetRemapping;
69
70 DataExtractor Data(CurStrSection, true, 0);
71 uint32_t LocalOffset = 0;
72 uint32_t PrevOffset = 0;
73 while (const char *s = Data.getCStr(&LocalOffset)) {
74 OffsetRemapping[PrevOffset] =
75 Strings.getOffset(s, LocalOffset - PrevOffset);
76 PrevOffset = LocalOffset;
77 }
78
79 Data = DataExtractor(CurStrOffsetSection, true, 0);
80
81 Out.SwitchSection(StrOffsetSection);
82
83 uint32_t Offset = 0;
84 uint64_t Size = CurStrOffsetSection.size();
85 while (Offset < Size) {
86 auto OldOffset = Data.getU32(&Offset);
87 auto NewOffset = OffsetRemapping[OldOffset];
88 Out.EmitIntValue(NewOffset, 4);
89 }
90 }
91
getCUAbbrev(StringRef Abbrev,uint64_t AbbrCode)92 static uint32_t getCUAbbrev(StringRef Abbrev, uint64_t AbbrCode) {
93 uint64_t CurCode;
94 uint32_t Offset = 0;
95 DataExtractor AbbrevData(Abbrev, true, 0);
96 while ((CurCode = AbbrevData.getULEB128(&Offset)) != AbbrCode) {
97 // Tag
98 AbbrevData.getULEB128(&Offset);
99 // DW_CHILDREN
100 AbbrevData.getU8(&Offset);
101 // Attributes
102 while (AbbrevData.getULEB128(&Offset) | AbbrevData.getULEB128(&Offset))
103 ;
104 }
105 return Offset;
106 }
107
108 struct CompileUnitIdentifiers {
109 uint64_t Signature = 0;
110 const char *Name = "";
111 const char *DWOName = "";
112 };
113
114 static Expected<const char *>
getIndexedString(uint32_t Form,DataExtractor InfoData,uint32_t & InfoOffset,StringRef StrOffsets,StringRef Str)115 getIndexedString(uint32_t Form, DataExtractor InfoData, uint32_t &InfoOffset,
116 StringRef StrOffsets, StringRef Str) {
117 if (Form == dwarf::DW_FORM_string)
118 return InfoData.getCStr(&InfoOffset);
119 if (Form != dwarf::DW_FORM_GNU_str_index)
120 return make_error<DWPError>(
121 "string field encoded without DW_FORM_string or DW_FORM_GNU_str_index");
122 auto StrIndex = InfoData.getULEB128(&InfoOffset);
123 DataExtractor StrOffsetsData(StrOffsets, true, 0);
124 uint32_t StrOffsetsOffset = 4 * StrIndex;
125 uint32_t StrOffset = StrOffsetsData.getU32(&StrOffsetsOffset);
126 DataExtractor StrData(Str, true, 0);
127 return StrData.getCStr(&StrOffset);
128 }
129
getCUIdentifiers(StringRef Abbrev,StringRef Info,StringRef StrOffsets,StringRef Str)130 static Expected<CompileUnitIdentifiers> getCUIdentifiers(StringRef Abbrev,
131 StringRef Info,
132 StringRef StrOffsets,
133 StringRef Str) {
134 uint32_t Offset = 0;
135 DataExtractor InfoData(Info, true, 0);
136 InfoData.getU32(&Offset); // Length
137 uint16_t Version = InfoData.getU16(&Offset);
138 InfoData.getU32(&Offset); // Abbrev offset (should be zero)
139 uint8_t AddrSize = InfoData.getU8(&Offset);
140
141 uint32_t AbbrCode = InfoData.getULEB128(&Offset);
142
143 DataExtractor AbbrevData(Abbrev, true, 0);
144 uint32_t AbbrevOffset = getCUAbbrev(Abbrev, AbbrCode);
145 uint64_t Tag = AbbrevData.getULEB128(&AbbrevOffset);
146 if (Tag != dwarf::DW_TAG_compile_unit)
147 return make_error<DWPError>("top level DIE is not a compile unit");
148 // DW_CHILDREN
149 AbbrevData.getU8(&AbbrevOffset);
150 uint32_t Name;
151 uint32_t Form;
152 CompileUnitIdentifiers ID;
153 while ((Name = AbbrevData.getULEB128(&AbbrevOffset)) |
154 (Form = AbbrevData.getULEB128(&AbbrevOffset)) &&
155 (Name != 0 || Form != 0)) {
156 switch (Name) {
157 case dwarf::DW_AT_name: {
158 Expected<const char *> EName =
159 getIndexedString(Form, InfoData, Offset, StrOffsets, Str);
160 if (!EName)
161 return EName.takeError();
162 ID.Name = *EName;
163 break;
164 }
165 case dwarf::DW_AT_GNU_dwo_name: {
166 Expected<const char *> EName =
167 getIndexedString(Form, InfoData, Offset, StrOffsets, Str);
168 if (!EName)
169 return EName.takeError();
170 ID.DWOName = *EName;
171 break;
172 }
173 case dwarf::DW_AT_GNU_dwo_id:
174 ID.Signature = InfoData.getU64(&Offset);
175 break;
176 default:
177 DWARFFormValue::skipValue(Form, InfoData, &Offset, Version, AddrSize);
178 }
179 }
180 return ID;
181 }
182
183 struct UnitIndexEntry {
184 DWARFUnitIndex::Entry::SectionContribution Contributions[8];
185 std::string Name;
186 std::string DWOName;
187 StringRef DWPName;
188 };
189
getSubsection(StringRef Section,const DWARFUnitIndex::Entry & Entry,DWARFSectionKind Kind)190 static StringRef getSubsection(StringRef Section,
191 const DWARFUnitIndex::Entry &Entry,
192 DWARFSectionKind Kind) {
193 const auto *Off = Entry.getOffset(Kind);
194 if (!Off)
195 return StringRef();
196 return Section.substr(Off->Offset, Off->Length);
197 }
198
addAllTypesFromDWP(MCStreamer & Out,MapVector<uint64_t,UnitIndexEntry> & TypeIndexEntries,const DWARFUnitIndex & TUIndex,MCSection * OutputTypes,StringRef Types,const UnitIndexEntry & TUEntry,uint32_t & TypesOffset)199 static void addAllTypesFromDWP(
200 MCStreamer &Out, MapVector<uint64_t, UnitIndexEntry> &TypeIndexEntries,
201 const DWARFUnitIndex &TUIndex, MCSection *OutputTypes, StringRef Types,
202 const UnitIndexEntry &TUEntry, uint32_t &TypesOffset) {
203 Out.SwitchSection(OutputTypes);
204 for (const DWARFUnitIndex::Entry &E : TUIndex.getRows()) {
205 auto *I = E.getOffsets();
206 if (!I)
207 continue;
208 auto P = TypeIndexEntries.insert(std::make_pair(E.getSignature(), TUEntry));
209 if (!P.second)
210 continue;
211 auto &Entry = P.first->second;
212 // Zero out the debug_info contribution
213 Entry.Contributions[0] = {};
214 for (auto Kind : TUIndex.getColumnKinds()) {
215 auto &C = Entry.Contributions[Kind - DW_SECT_INFO];
216 C.Offset += I->Offset;
217 C.Length = I->Length;
218 ++I;
219 }
220 auto &C = Entry.Contributions[DW_SECT_TYPES - DW_SECT_INFO];
221 Out.EmitBytes(Types.substr(
222 C.Offset - TUEntry.Contributions[DW_SECT_TYPES - DW_SECT_INFO].Offset,
223 C.Length));
224 C.Offset = TypesOffset;
225 TypesOffset += C.Length;
226 }
227 }
228
addAllTypes(MCStreamer & Out,MapVector<uint64_t,UnitIndexEntry> & TypeIndexEntries,MCSection * OutputTypes,const std::vector<StringRef> & TypesSections,const UnitIndexEntry & CUEntry,uint32_t & TypesOffset)229 static void addAllTypes(MCStreamer &Out,
230 MapVector<uint64_t, UnitIndexEntry> &TypeIndexEntries,
231 MCSection *OutputTypes,
232 const std::vector<StringRef> &TypesSections,
233 const UnitIndexEntry &CUEntry, uint32_t &TypesOffset) {
234 for (StringRef Types : TypesSections) {
235 Out.SwitchSection(OutputTypes);
236 uint32_t Offset = 0;
237 DataExtractor Data(Types, true, 0);
238 while (Data.isValidOffset(Offset)) {
239 UnitIndexEntry Entry = CUEntry;
240 // Zero out the debug_info contribution
241 Entry.Contributions[0] = {};
242 auto &C = Entry.Contributions[DW_SECT_TYPES - DW_SECT_INFO];
243 C.Offset = TypesOffset;
244 auto PrevOffset = Offset;
245 // Length of the unit, including the 4 byte length field.
246 C.Length = Data.getU32(&Offset) + 4;
247
248 Data.getU16(&Offset); // Version
249 Data.getU32(&Offset); // Abbrev offset
250 Data.getU8(&Offset); // Address size
251 auto Signature = Data.getU64(&Offset);
252 Offset = PrevOffset + C.Length;
253
254 auto P = TypeIndexEntries.insert(std::make_pair(Signature, Entry));
255 if (!P.second)
256 continue;
257
258 Out.EmitBytes(Types.substr(PrevOffset, C.Length));
259 TypesOffset += C.Length;
260 }
261 }
262 }
263
264 static void
writeIndexTable(MCStreamer & Out,ArrayRef<unsigned> ContributionOffsets,const MapVector<uint64_t,UnitIndexEntry> & IndexEntries,uint32_t DWARFUnitIndex::Entry::SectionContribution::* Field)265 writeIndexTable(MCStreamer &Out, ArrayRef<unsigned> ContributionOffsets,
266 const MapVector<uint64_t, UnitIndexEntry> &IndexEntries,
267 uint32_t DWARFUnitIndex::Entry::SectionContribution::*Field) {
268 for (const auto &E : IndexEntries)
269 for (size_t i = 0; i != array_lengthof(E.second.Contributions); ++i)
270 if (ContributionOffsets[i])
271 Out.EmitIntValue(E.second.Contributions[i].*Field, 4);
272 }
273
274 static void
writeIndex(MCStreamer & Out,MCSection * Section,ArrayRef<unsigned> ContributionOffsets,const MapVector<uint64_t,UnitIndexEntry> & IndexEntries)275 writeIndex(MCStreamer &Out, MCSection *Section,
276 ArrayRef<unsigned> ContributionOffsets,
277 const MapVector<uint64_t, UnitIndexEntry> &IndexEntries) {
278 if (IndexEntries.empty())
279 return;
280
281 unsigned Columns = 0;
282 for (auto &C : ContributionOffsets)
283 if (C)
284 ++Columns;
285
286 std::vector<unsigned> Buckets(NextPowerOf2(3 * IndexEntries.size() / 2));
287 uint64_t Mask = Buckets.size() - 1;
288 size_t i = 0;
289 for (const auto &P : IndexEntries) {
290 auto S = P.first;
291 auto H = S & Mask;
292 auto HP = ((S >> 32) & Mask) | 1;
293 while (Buckets[H]) {
294 assert(S != IndexEntries.begin()[Buckets[H] - 1].first &&
295 "Duplicate unit");
296 H = (H + HP) & Mask;
297 }
298 Buckets[H] = i + 1;
299 ++i;
300 }
301
302 Out.SwitchSection(Section);
303 Out.EmitIntValue(2, 4); // Version
304 Out.EmitIntValue(Columns, 4); // Columns
305 Out.EmitIntValue(IndexEntries.size(), 4); // Num Units
306 Out.EmitIntValue(Buckets.size(), 4); // Num Buckets
307
308 // Write the signatures.
309 for (const auto &I : Buckets)
310 Out.EmitIntValue(I ? IndexEntries.begin()[I - 1].first : 0, 8);
311
312 // Write the indexes.
313 for (const auto &I : Buckets)
314 Out.EmitIntValue(I, 4);
315
316 // Write the column headers (which sections will appear in the table)
317 for (size_t i = 0; i != ContributionOffsets.size(); ++i)
318 if (ContributionOffsets[i])
319 Out.EmitIntValue(i + DW_SECT_INFO, 4);
320
321 // Write the offsets.
322 writeIndexTable(Out, ContributionOffsets, IndexEntries,
323 &DWARFUnitIndex::Entry::SectionContribution::Offset);
324
325 // Write the lengths.
326 writeIndexTable(Out, ContributionOffsets, IndexEntries,
327 &DWARFUnitIndex::Entry::SectionContribution::Length);
328 }
consumeCompressedDebugSectionHeader(StringRef & data,uint64_t & OriginalSize)329 static bool consumeCompressedDebugSectionHeader(StringRef &data,
330 uint64_t &OriginalSize) {
331 // Consume "ZLIB" prefix.
332 if (!data.startswith("ZLIB"))
333 return false;
334 data = data.substr(4);
335 // Consume uncompressed section size (big-endian 8 bytes).
336 DataExtractor extractor(data, false, 8);
337 uint32_t Offset = 0;
338 OriginalSize = extractor.getU64(&Offset);
339 if (Offset == 0)
340 return false;
341 data = data.substr(Offset);
342 return true;
343 }
344
buildDWODescription(StringRef Name,StringRef DWPName,StringRef DWOName)345 std::string buildDWODescription(StringRef Name, StringRef DWPName, StringRef DWOName) {
346 std::string Text = "\'";
347 Text += Name;
348 Text += '\'';
349 if (!DWPName.empty()) {
350 Text += " (from ";
351 if (!DWOName.empty()) {
352 Text += '\'';
353 Text += DWOName;
354 Text += "' in ";
355 }
356 Text += '\'';
357 Text += DWPName;
358 Text += "')";
359 }
360 return Text;
361 }
362
handleCompressedSection(std::deque<SmallString<32>> & UncompressedSections,StringRef & Name,StringRef & Contents)363 static Error handleCompressedSection(
364 std::deque<SmallString<32>> &UncompressedSections, StringRef &Name,
365 StringRef &Contents) {
366 if (!Name.startswith("zdebug_"))
367 return Error();
368 UncompressedSections.emplace_back();
369 uint64_t OriginalSize;
370 if (!zlib::isAvailable())
371 return make_error<DWPError>("zlib not available");
372 if (!consumeCompressedDebugSectionHeader(Contents, OriginalSize) ||
373 zlib::uncompress(Contents, UncompressedSections.back(), OriginalSize) !=
374 zlib::StatusOK)
375 return make_error<DWPError>(
376 ("failure while decompressing compressed section: '" + Name + "\'")
377 .str());
378 Name = Name.substr(1);
379 Contents = UncompressedSections.back();
380 return Error();
381 }
382
handleSection(const StringMap<std::pair<MCSection *,DWARFSectionKind>> & KnownSections,const MCSection * StrSection,const MCSection * StrOffsetSection,const MCSection * TypesSection,const MCSection * CUIndexSection,const MCSection * TUIndexSection,const SectionRef & Section,MCStreamer & Out,std::deque<SmallString<32>> & UncompressedSections,uint32_t (& ContributionOffsets)[8],UnitIndexEntry & CurEntry,StringRef & CurStrSection,StringRef & CurStrOffsetSection,std::vector<StringRef> & CurTypesSection,StringRef & InfoSection,StringRef & AbbrevSection,StringRef & CurCUIndexSection,StringRef & CurTUIndexSection)383 static Error handleSection(
384 const StringMap<std::pair<MCSection *, DWARFSectionKind>> &KnownSections,
385 const MCSection *StrSection, const MCSection *StrOffsetSection,
386 const MCSection *TypesSection, const MCSection *CUIndexSection,
387 const MCSection *TUIndexSection, const SectionRef &Section, MCStreamer &Out,
388 std::deque<SmallString<32>> &UncompressedSections,
389 uint32_t (&ContributionOffsets)[8], UnitIndexEntry &CurEntry,
390 StringRef &CurStrSection, StringRef &CurStrOffsetSection,
391 std::vector<StringRef> &CurTypesSection, StringRef &InfoSection,
392 StringRef &AbbrevSection, StringRef &CurCUIndexSection,
393 StringRef &CurTUIndexSection) {
394 if (Section.isBSS())
395 return Error();
396
397 if (Section.isVirtual())
398 return Error();
399
400 StringRef Name;
401 if (std::error_code Err = Section.getName(Name))
402 return errorCodeToError(Err);
403
404 Name = Name.substr(Name.find_first_not_of("._"));
405
406 StringRef Contents;
407 if (auto Err = Section.getContents(Contents))
408 return errorCodeToError(Err);
409
410 if (auto Err = handleCompressedSection(UncompressedSections, Name, Contents))
411 return Err;
412
413 auto SectionPair = KnownSections.find(Name);
414 if (SectionPair == KnownSections.end())
415 return Error();
416
417 if (DWARFSectionKind Kind = SectionPair->second.second) {
418 auto Index = Kind - DW_SECT_INFO;
419 if (Kind != DW_SECT_TYPES) {
420 CurEntry.Contributions[Index].Offset = ContributionOffsets[Index];
421 ContributionOffsets[Index] +=
422 (CurEntry.Contributions[Index].Length = Contents.size());
423 }
424
425 switch (Kind) {
426 case DW_SECT_INFO:
427 InfoSection = Contents;
428 break;
429 case DW_SECT_ABBREV:
430 AbbrevSection = Contents;
431 break;
432 default:
433 break;
434 }
435 }
436
437 MCSection *OutSection = SectionPair->second.first;
438 if (OutSection == StrOffsetSection)
439 CurStrOffsetSection = Contents;
440 else if (OutSection == StrSection)
441 CurStrSection = Contents;
442 else if (OutSection == TypesSection)
443 CurTypesSection.push_back(Contents);
444 else if (OutSection == CUIndexSection)
445 CurCUIndexSection = Contents;
446 else if (OutSection == TUIndexSection)
447 CurTUIndexSection = Contents;
448 else {
449 Out.SwitchSection(OutSection);
450 Out.EmitBytes(Contents);
451 }
452 return Error();
453 }
454
455 static Error
buildDuplicateError(const std::pair<uint64_t,UnitIndexEntry> & PrevE,const CompileUnitIdentifiers & ID,StringRef DWPName)456 buildDuplicateError(const std::pair<uint64_t, UnitIndexEntry> &PrevE,
457 const CompileUnitIdentifiers &ID, StringRef DWPName) {
458 return make_error<DWPError>(
459 std::string("Duplicate DWO ID (") + utohexstr(PrevE.first) + ") in " +
460 buildDWODescription(PrevE.second.Name, PrevE.second.DWPName,
461 PrevE.second.DWOName) +
462 " and " + buildDWODescription(ID.Name, DWPName, ID.DWOName));
463 }
464
write(MCStreamer & Out,ArrayRef<std::string> Inputs)465 static Error write(MCStreamer &Out, ArrayRef<std::string> Inputs) {
466 const auto &MCOFI = *Out.getContext().getObjectFileInfo();
467 MCSection *const StrSection = MCOFI.getDwarfStrDWOSection();
468 MCSection *const StrOffsetSection = MCOFI.getDwarfStrOffDWOSection();
469 MCSection *const TypesSection = MCOFI.getDwarfTypesDWOSection();
470 MCSection *const CUIndexSection = MCOFI.getDwarfCUIndexSection();
471 MCSection *const TUIndexSection = MCOFI.getDwarfTUIndexSection();
472 const StringMap<std::pair<MCSection *, DWARFSectionKind>> KnownSections = {
473 {"debug_info.dwo", {MCOFI.getDwarfInfoDWOSection(), DW_SECT_INFO}},
474 {"debug_types.dwo", {MCOFI.getDwarfTypesDWOSection(), DW_SECT_TYPES}},
475 {"debug_str_offsets.dwo", {StrOffsetSection, DW_SECT_STR_OFFSETS}},
476 {"debug_str.dwo", {StrSection, static_cast<DWARFSectionKind>(0)}},
477 {"debug_loc.dwo", {MCOFI.getDwarfLocDWOSection(), DW_SECT_LOC}},
478 {"debug_line.dwo", {MCOFI.getDwarfLineDWOSection(), DW_SECT_LINE}},
479 {"debug_abbrev.dwo", {MCOFI.getDwarfAbbrevDWOSection(), DW_SECT_ABBREV}},
480 {"debug_cu_index", {CUIndexSection, static_cast<DWARFSectionKind>(0)}},
481 {"debug_tu_index", {TUIndexSection, static_cast<DWARFSectionKind>(0)}}};
482
483 MapVector<uint64_t, UnitIndexEntry> IndexEntries;
484 MapVector<uint64_t, UnitIndexEntry> TypeIndexEntries;
485
486 uint32_t ContributionOffsets[8] = {};
487
488 DWPStringPool Strings(Out, StrSection);
489
490 SmallVector<OwningBinary<object::ObjectFile>, 128> Objects;
491 Objects.reserve(Inputs.size());
492
493 std::deque<SmallString<32>> UncompressedSections;
494
495 for (const auto &Input : Inputs) {
496 auto ErrOrObj = object::ObjectFile::createObjectFile(Input);
497 if (!ErrOrObj)
498 return ErrOrObj.takeError();
499
500 auto &Obj = *ErrOrObj->getBinary();
501 Objects.push_back(std::move(*ErrOrObj));
502
503 UnitIndexEntry CurEntry = {};
504
505 StringRef CurStrSection;
506 StringRef CurStrOffsetSection;
507 std::vector<StringRef> CurTypesSection;
508 StringRef InfoSection;
509 StringRef AbbrevSection;
510 StringRef CurCUIndexSection;
511 StringRef CurTUIndexSection;
512
513 for (const auto &Section : Obj.sections())
514 if (auto Err = handleSection(
515 KnownSections, StrSection, StrOffsetSection, TypesSection,
516 CUIndexSection, TUIndexSection, Section, Out,
517 UncompressedSections, ContributionOffsets, CurEntry,
518 CurStrSection, CurStrOffsetSection, CurTypesSection, InfoSection,
519 AbbrevSection, CurCUIndexSection, CurTUIndexSection))
520 return Err;
521
522 if (InfoSection.empty())
523 continue;
524
525 writeStringsAndOffsets(Out, Strings, StrOffsetSection, CurStrSection,
526 CurStrOffsetSection);
527
528 if (CurCUIndexSection.empty()) {
529 Expected<CompileUnitIdentifiers> EID = getCUIdentifiers(
530 AbbrevSection, InfoSection, CurStrOffsetSection, CurStrSection);
531 if (!EID)
532 return EID.takeError();
533 const auto &ID = *EID;
534 auto P = IndexEntries.insert(std::make_pair(ID.Signature, CurEntry));
535 if (!P.second)
536 return buildDuplicateError(*P.first, ID, "");
537 P.first->second.Name = ID.Name;
538 P.first->second.DWOName = ID.DWOName;
539 addAllTypes(Out, TypeIndexEntries, TypesSection, CurTypesSection,
540 CurEntry, ContributionOffsets[DW_SECT_TYPES - DW_SECT_INFO]);
541 continue;
542 }
543
544 DWARFUnitIndex CUIndex(DW_SECT_INFO);
545 DataExtractor CUIndexData(CurCUIndexSection, Obj.isLittleEndian(), 0);
546 if (!CUIndex.parse(CUIndexData))
547 return make_error<DWPError>("Failed to parse cu_index");
548
549 for (const DWARFUnitIndex::Entry &E : CUIndex.getRows()) {
550 auto *I = E.getOffsets();
551 if (!I)
552 continue;
553 auto P = IndexEntries.insert(std::make_pair(E.getSignature(), CurEntry));
554 Expected<CompileUnitIdentifiers> EID = getCUIdentifiers(
555 getSubsection(AbbrevSection, E, DW_SECT_ABBREV),
556 getSubsection(InfoSection, E, DW_SECT_INFO),
557 getSubsection(CurStrOffsetSection, E, DW_SECT_STR_OFFSETS),
558 CurStrSection);
559 if (!EID)
560 return EID.takeError();
561 const auto &ID = *EID;
562 if (!P.second)
563 return buildDuplicateError(*P.first, ID, Input);
564 auto &NewEntry = P.first->second;
565 NewEntry.Name = ID.Name;
566 NewEntry.DWOName = ID.DWOName;
567 NewEntry.DWPName = Input;
568 for (auto Kind : CUIndex.getColumnKinds()) {
569 auto &C = NewEntry.Contributions[Kind - DW_SECT_INFO];
570 C.Offset += I->Offset;
571 C.Length = I->Length;
572 ++I;
573 }
574 }
575
576 if (!CurTypesSection.empty()) {
577 if (CurTypesSection.size() != 1)
578 return make_error<DWPError>("multiple type unit sections in .dwp file");
579 DWARFUnitIndex TUIndex(DW_SECT_TYPES);
580 DataExtractor TUIndexData(CurTUIndexSection, Obj.isLittleEndian(), 0);
581 if (!TUIndex.parse(TUIndexData))
582 return make_error<DWPError>("Failed to parse tu_index");
583 addAllTypesFromDWP(Out, TypeIndexEntries, TUIndex, TypesSection,
584 CurTypesSection.front(), CurEntry,
585 ContributionOffsets[DW_SECT_TYPES - DW_SECT_INFO]);
586 }
587 }
588
589 // Lie about there being no info contributions so the TU index only includes
590 // the type unit contribution
591 ContributionOffsets[0] = 0;
592 writeIndex(Out, MCOFI.getDwarfTUIndexSection(), ContributionOffsets,
593 TypeIndexEntries);
594
595 // Lie about the type contribution
596 ContributionOffsets[DW_SECT_TYPES - DW_SECT_INFO] = 0;
597 // Unlie about the info contribution
598 ContributionOffsets[0] = 1;
599
600 writeIndex(Out, MCOFI.getDwarfCUIndexSection(), ContributionOffsets,
601 IndexEntries);
602
603 return Error();
604 }
605
error(const Twine & Error,const Twine & Context)606 static int error(const Twine &Error, const Twine &Context) {
607 errs() << Twine("while processing ") + Context + ":\n";
608 errs() << Twine("error: ") + Error + "\n";
609 return 1;
610 }
611
main(int argc,char ** argv)612 int main(int argc, char **argv) {
613
614 ParseCommandLineOptions(argc, argv, "merge split dwarf (.dwo) files");
615
616 llvm::InitializeAllTargetInfos();
617 llvm::InitializeAllTargetMCs();
618 llvm::InitializeAllTargets();
619 llvm::InitializeAllAsmPrinters();
620
621 std::string ErrorStr;
622 StringRef Context = "dwarf streamer init";
623
624 Triple TheTriple("x86_64-linux-gnu");
625
626 // Get the target.
627 const Target *TheTarget =
628 TargetRegistry::lookupTarget("", TheTriple, ErrorStr);
629 if (!TheTarget)
630 return error(ErrorStr, Context);
631 std::string TripleName = TheTriple.getTriple();
632
633 // Create all the MC Objects.
634 std::unique_ptr<MCRegisterInfo> MRI(TheTarget->createMCRegInfo(TripleName));
635 if (!MRI)
636 return error(Twine("no register info for target ") + TripleName, Context);
637
638 std::unique_ptr<MCAsmInfo> MAI(TheTarget->createMCAsmInfo(*MRI, TripleName));
639 if (!MAI)
640 return error("no asm info for target " + TripleName, Context);
641
642 MCObjectFileInfo MOFI;
643 MCContext MC(MAI.get(), MRI.get(), &MOFI);
644 MOFI.InitMCObjectFileInfo(TheTriple, /*PIC*/ false, CodeModel::Default, MC);
645
646 auto MAB = TheTarget->createMCAsmBackend(*MRI, TripleName, "");
647 if (!MAB)
648 return error("no asm backend for target " + TripleName, Context);
649
650 std::unique_ptr<MCInstrInfo> MII(TheTarget->createMCInstrInfo());
651 if (!MII)
652 return error("no instr info info for target " + TripleName, Context);
653
654 std::unique_ptr<MCSubtargetInfo> MSTI(
655 TheTarget->createMCSubtargetInfo(TripleName, "", ""));
656 if (!MSTI)
657 return error("no subtarget info for target " + TripleName, Context);
658
659 MCCodeEmitter *MCE = TheTarget->createMCCodeEmitter(*MII, *MRI, MC);
660 if (!MCE)
661 return error("no code emitter for target " + TripleName, Context);
662
663 // Create the output file.
664 std::error_code EC;
665 raw_fd_ostream OutFile(OutputFilename, EC, sys::fs::F_None);
666 if (EC)
667 return error(Twine(OutputFilename) + ": " + EC.message(), Context);
668
669 MCTargetOptions MCOptions = InitMCTargetOptionsFromFlags();
670 std::unique_ptr<MCStreamer> MS(TheTarget->createMCObjectStreamer(
671 TheTriple, MC, *MAB, OutFile, MCE, *MSTI, MCOptions.MCRelaxAll,
672 MCOptions.MCIncrementalLinkerCompatible,
673 /*DWARFMustBeAtTheEnd*/ false));
674 if (!MS)
675 return error("no object streamer for target " + TripleName, Context);
676
677 if (auto Err = write(*MS, InputFiles)) {
678 logAllUnhandledErrors(std::move(Err), errs(), "error: ");
679 return 1;
680 }
681
682 MS->Finish();
683 }
684