1//===-- llvm-dwp.cpp - Split DWARF merging tool for llvm ------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// A utility for merging DWARF 5 Split DWARF .dwo files into .dwp (DWARF
10// package files).
11//
12//===----------------------------------------------------------------------===//
13#include "llvm/DWP/DWP.h"
14#include "llvm/ADT/Twine.h"
15#include "llvm/DWP/DWPError.h"
16#include "llvm/MC/MCContext.h"
17#include "llvm/MC/MCObjectFileInfo.h"
18#include "llvm/MC/MCTargetOptionsCommandFlags.h"
19#include "llvm/Object/Decompressor.h"
20#include "llvm/Object/ELFObjectFile.h"
21#include <limits>
22
23using namespace llvm;
24using namespace llvm::object;
25
26static mc::RegisterMCTargetOptionsFlags MCTargetOptionsFlags;
27
28// Returns the size of debug_str_offsets section headers in bytes.
29static uint64_t debugStrOffsetsHeaderSize(DataExtractor StrOffsetsData,
30 uint16_t DwarfVersion) {
31 if (DwarfVersion <= 4)
32 return 0; // There is no header before dwarf 5.
33 uint64_t Offset = 0;
34 uint64_t Length = StrOffsetsData.getU32(offset_ptr: &Offset);
35 if (Length == llvm::dwarf::DW_LENGTH_DWARF64)
36 return 16; // unit length: 12 bytes, version: 2 bytes, padding: 2 bytes.
37 return 8; // unit length: 4 bytes, version: 2 bytes, padding: 2 bytes.
38}
39
40static uint64_t getCUAbbrev(StringRef Abbrev, uint64_t AbbrCode) {
41 uint64_t Offset = 0;
42 DataExtractor AbbrevData(Abbrev, true, 0);
43 while (AbbrevData.getULEB128(offset_ptr: &Offset) != AbbrCode) {
44 // Tag
45 AbbrevData.getULEB128(offset_ptr: &Offset);
46 // DW_CHILDREN
47 AbbrevData.getU8(offset_ptr: &Offset);
48 // Attributes
49 while (AbbrevData.getULEB128(offset_ptr: &Offset) | AbbrevData.getULEB128(offset_ptr: &Offset))
50 ;
51 }
52 return Offset;
53}
54
55static Expected<const char *>
56getIndexedString(dwarf::Form Form, DataExtractor InfoData, uint64_t &InfoOffset,
57 StringRef StrOffsets, StringRef Str, uint16_t Version) {
58 if (Form == dwarf::DW_FORM_string)
59 return InfoData.getCStr(OffsetPtr: &InfoOffset);
60 uint64_t StrIndex;
61 switch (Form) {
62 case dwarf::DW_FORM_strx1:
63 StrIndex = InfoData.getU8(offset_ptr: &InfoOffset);
64 break;
65 case dwarf::DW_FORM_strx2:
66 StrIndex = InfoData.getU16(offset_ptr: &InfoOffset);
67 break;
68 case dwarf::DW_FORM_strx3:
69 StrIndex = InfoData.getU24(OffsetPtr: &InfoOffset);
70 break;
71 case dwarf::DW_FORM_strx4:
72 StrIndex = InfoData.getU32(offset_ptr: &InfoOffset);
73 break;
74 case dwarf::DW_FORM_strx:
75 case dwarf::DW_FORM_GNU_str_index:
76 StrIndex = InfoData.getULEB128(offset_ptr: &InfoOffset);
77 break;
78 default:
79 return make_error<DWPError>(
80 Args: "string field must be encoded with one of the following: "
81 "DW_FORM_string, DW_FORM_strx, DW_FORM_strx1, DW_FORM_strx2, "
82 "DW_FORM_strx3, DW_FORM_strx4, or DW_FORM_GNU_str_index.");
83 }
84 DataExtractor StrOffsetsData(StrOffsets, true, 0);
85 uint64_t StrOffsetsOffset = 4 * StrIndex;
86 StrOffsetsOffset += debugStrOffsetsHeaderSize(StrOffsetsData, DwarfVersion: Version);
87
88 uint64_t StrOffset = StrOffsetsData.getU32(offset_ptr: &StrOffsetsOffset);
89 DataExtractor StrData(Str, true, 0);
90 return StrData.getCStr(OffsetPtr: &StrOffset);
91}
92
93static Expected<CompileUnitIdentifiers>
94getCUIdentifiers(InfoSectionUnitHeader &Header, StringRef Abbrev,
95 StringRef Info, StringRef StrOffsets, StringRef Str) {
96 DataExtractor InfoData(Info, true, 0);
97 uint64_t Offset = Header.HeaderSize;
98 if (Header.Version >= 5 && Header.UnitType != dwarf::DW_UT_split_compile)
99 return make_error<DWPError>(
100 Args: std::string("unit type DW_UT_split_compile type not found in "
101 "debug_info header. Unexpected unit type 0x" +
102 utostr(X: Header.UnitType) + " found"));
103
104 CompileUnitIdentifiers ID;
105
106 uint32_t AbbrCode = InfoData.getULEB128(offset_ptr: &Offset);
107 DataExtractor AbbrevData(Abbrev, true, 0);
108 uint64_t AbbrevOffset = getCUAbbrev(Abbrev, AbbrCode);
109 auto Tag = static_cast<dwarf::Tag>(AbbrevData.getULEB128(offset_ptr: &AbbrevOffset));
110 if (Tag != dwarf::DW_TAG_compile_unit)
111 return make_error<DWPError>(Args: "top level DIE is not a compile unit");
112 // DW_CHILDREN
113 AbbrevData.getU8(offset_ptr: &AbbrevOffset);
114 uint32_t Name;
115 dwarf::Form Form;
116 while ((Name = AbbrevData.getULEB128(offset_ptr: &AbbrevOffset)) |
117 (Form = static_cast<dwarf::Form>(
118 AbbrevData.getULEB128(offset_ptr: &AbbrevOffset))) &&
119 (Name != 0 || Form != 0)) {
120 switch (Name) {
121 case dwarf::DW_AT_name: {
122 Expected<const char *> EName = getIndexedString(
123 Form, InfoData, InfoOffset&: Offset, StrOffsets, Str, Version: Header.Version);
124 if (!EName)
125 return EName.takeError();
126 ID.Name = *EName;
127 break;
128 }
129 case dwarf::DW_AT_GNU_dwo_name:
130 case dwarf::DW_AT_dwo_name: {
131 Expected<const char *> EName = getIndexedString(
132 Form, InfoData, InfoOffset&: Offset, StrOffsets, Str, Version: Header.Version);
133 if (!EName)
134 return EName.takeError();
135 ID.DWOName = *EName;
136 break;
137 }
138 case dwarf::DW_AT_GNU_dwo_id:
139 Header.Signature = InfoData.getU64(offset_ptr: &Offset);
140 break;
141 default:
142 DWARFFormValue::skipValue(
143 Form, DebugInfoData: InfoData, OffsetPtr: &Offset,
144 FormParams: dwarf::FormParams({.Version: Header.Version, .AddrSize: Header.AddrSize, .Format: Header.Format}));
145 }
146 }
147 if (!Header.Signature)
148 return make_error<DWPError>(Args: "compile unit missing dwo_id");
149 ID.Signature = *Header.Signature;
150 return ID;
151}
152
153static bool isSupportedSectionKind(DWARFSectionKind Kind) {
154 return Kind != DW_SECT_EXT_unknown;
155}
156
157// Convert an internal section identifier into the index to use with
158// UnitIndexEntry::Contributions.
159static unsigned getContributionIndex(DWARFSectionKind Kind,
160 uint32_t IndexVersion) {
161 assert(serializeSectionKind(Kind, IndexVersion) >= DW_SECT_INFO);
162 return serializeSectionKind(Kind, IndexVersion) - DW_SECT_INFO;
163}
164
165// Convert a UnitIndexEntry::Contributions index to the corresponding on-disk
166// value of the section identifier.
167static unsigned getOnDiskSectionId(unsigned Index) {
168 return Index + DW_SECT_INFO;
169}
170
171static StringRef getSubsection(StringRef Section,
172 const DWARFUnitIndex::Entry &Entry,
173 DWARFSectionKind Kind) {
174 const auto *Off = Entry.getContribution(Sec: Kind);
175 if (!Off)
176 return StringRef();
177 return Section.substr(Start: Off->getOffset(), N: Off->getLength());
178}
179
180static Error sectionOverflowErrorOrWarning(uint32_t PrevOffset,
181 uint32_t OverflowedOffset,
182 StringRef SectionName,
183 OnCuIndexOverflow OverflowOptValue,
184 bool &AnySectionOverflow) {
185 std::string Msg =
186 (SectionName +
187 Twine(" Section Contribution Offset overflow 4G. Previous Offset ") +
188 Twine(PrevOffset) + Twine(", After overflow offset ") +
189 Twine(OverflowedOffset) + Twine("."))
190 .str();
191 if (OverflowOptValue == OnCuIndexOverflow::Continue) {
192 WithColor::defaultWarningHandler(Warning: make_error<DWPError>(Args&: Msg));
193 return Error::success();
194 } else if (OverflowOptValue == OnCuIndexOverflow::SoftStop) {
195 AnySectionOverflow = true;
196 WithColor::defaultWarningHandler(Warning: make_error<DWPError>(Args&: Msg));
197 return Error::success();
198 }
199 return make_error<DWPError>(Args&: Msg);
200}
201
202static Error addAllTypesFromDWP(
203 MCStreamer &Out, MapVector<uint64_t, UnitIndexEntry> &TypeIndexEntries,
204 const DWARFUnitIndex &TUIndex, MCSection *OutputTypes, StringRef Types,
205 const UnitIndexEntry &TUEntry, uint32_t &TypesOffset,
206 unsigned TypesContributionIndex, OnCuIndexOverflow OverflowOptValue,
207 bool &AnySectionOverflow) {
208 Out.switchSection(Section: OutputTypes);
209 for (const DWARFUnitIndex::Entry &E : TUIndex.getRows()) {
210 auto *I = E.getContributions();
211 if (!I)
212 continue;
213 auto P = TypeIndexEntries.insert(KV: std::make_pair(x: E.getSignature(), y: TUEntry));
214 if (!P.second)
215 continue;
216 auto &Entry = P.first->second;
217 // Zero out the debug_info contribution
218 Entry.Contributions[0] = {};
219 for (auto Kind : TUIndex.getColumnKinds()) {
220 if (!isSupportedSectionKind(Kind))
221 continue;
222 auto &C =
223 Entry.Contributions[getContributionIndex(Kind, IndexVersion: TUIndex.getVersion())];
224 C.setOffset(C.getOffset() + I->getOffset());
225 C.setLength(I->getLength());
226 ++I;
227 }
228 auto &C = Entry.Contributions[TypesContributionIndex];
229 Out.emitBytes(Data: Types.substr(
230 Start: C.getOffset() -
231 TUEntry.Contributions[TypesContributionIndex].getOffset(),
232 N: C.getLength()));
233 C.setOffset(TypesOffset);
234 uint32_t OldOffset = TypesOffset;
235 static_assert(sizeof(OldOffset) == sizeof(TypesOffset));
236 TypesOffset += C.getLength();
237 if (OldOffset > TypesOffset) {
238 if (Error Err = sectionOverflowErrorOrWarning(PrevOffset: OldOffset, OverflowedOffset: TypesOffset,
239 SectionName: "Types", OverflowOptValue,
240 AnySectionOverflow))
241 return Err;
242 if (AnySectionOverflow) {
243 TypesOffset = OldOffset;
244 return Error::success();
245 }
246 }
247 }
248 return Error::success();
249}
250
251static Error addAllTypesFromTypesSection(
252 MCStreamer &Out, MapVector<uint64_t, UnitIndexEntry> &TypeIndexEntries,
253 MCSection *OutputTypes, const std::vector<StringRef> &TypesSections,
254 const UnitIndexEntry &CUEntry, uint32_t &TypesOffset,
255 OnCuIndexOverflow OverflowOptValue, bool &AnySectionOverflow) {
256 for (StringRef Types : TypesSections) {
257 Out.switchSection(Section: OutputTypes);
258 uint64_t Offset = 0;
259 DataExtractor Data(Types, true, 0);
260 while (Data.isValidOffset(offset: Offset)) {
261 UnitIndexEntry Entry = CUEntry;
262 // Zero out the debug_info contribution
263 Entry.Contributions[0] = {};
264 auto &C = Entry.Contributions[getContributionIndex(Kind: DW_SECT_EXT_TYPES, IndexVersion: 2)];
265 C.setOffset(TypesOffset);
266 auto PrevOffset = Offset;
267 // Length of the unit, including the 4 byte length field.
268 C.setLength(Data.getU32(offset_ptr: &Offset) + 4);
269
270 Data.getU16(offset_ptr: &Offset); // Version
271 Data.getU32(offset_ptr: &Offset); // Abbrev offset
272 Data.getU8(offset_ptr: &Offset); // Address size
273 auto Signature = Data.getU64(offset_ptr: &Offset);
274 Offset = PrevOffset + C.getLength32();
275
276 auto P = TypeIndexEntries.insert(KV: std::make_pair(x&: Signature, y&: Entry));
277 if (!P.second)
278 continue;
279
280 Out.emitBytes(Data: Types.substr(Start: PrevOffset, N: C.getLength32()));
281 uint32_t OldOffset = TypesOffset;
282 TypesOffset += C.getLength32();
283 if (OldOffset > TypesOffset) {
284 if (Error Err = sectionOverflowErrorOrWarning(PrevOffset: OldOffset, OverflowedOffset: TypesOffset,
285 SectionName: "Types", OverflowOptValue,
286 AnySectionOverflow))
287 return Err;
288 if (AnySectionOverflow) {
289 TypesOffset = OldOffset;
290 return Error::success();
291 }
292 }
293 }
294 }
295 return Error::success();
296}
297
298static std::string buildDWODescription(StringRef Name, StringRef DWPName,
299 StringRef DWOName) {
300 std::string Text = "\'";
301 Text += Name;
302 Text += '\'';
303 bool HasDWO = !DWOName.empty();
304 bool HasDWP = !DWPName.empty();
305 if (HasDWO || HasDWP) {
306 Text += " (from ";
307 if (HasDWO) {
308 Text += '\'';
309 Text += DWOName;
310 Text += '\'';
311 }
312 if (HasDWO && HasDWP)
313 Text += " in ";
314 if (!DWPName.empty()) {
315 Text += '\'';
316 Text += DWPName;
317 Text += '\'';
318 }
319 Text += ")";
320 }
321 return Text;
322}
323
324static Error createError(StringRef Name, Error E) {
325 return make_error<DWPError>(
326 Args: ("failure while decompressing compressed section: '" + Name + "', " +
327 llvm::toString(E: std::move(E)))
328 .str());
329}
330
331static Error
332handleCompressedSection(std::deque<SmallString<32>> &UncompressedSections,
333 SectionRef Sec, StringRef Name, StringRef &Contents) {
334 auto *Obj = dyn_cast<ELFObjectFileBase>(Val: Sec.getObject());
335 if (!Obj ||
336 !(static_cast<ELFSectionRef>(Sec).getFlags() & ELF::SHF_COMPRESSED))
337 return Error::success();
338 bool IsLE = isa<object::ELF32LEObjectFile>(Val: Obj) ||
339 isa<object::ELF64LEObjectFile>(Val: Obj);
340 bool Is64 = isa<object::ELF64LEObjectFile>(Val: Obj) ||
341 isa<object::ELF64BEObjectFile>(Val: Obj);
342 Expected<Decompressor> Dec = Decompressor::create(Name, Data: Contents, IsLE, Is64Bit: Is64);
343 if (!Dec)
344 return createError(Name, E: Dec.takeError());
345
346 UncompressedSections.emplace_back();
347 if (Error E = Dec->resizeAndDecompress(Out&: UncompressedSections.back()))
348 return createError(Name, E: std::move(E));
349
350 Contents = UncompressedSections.back();
351 return Error::success();
352}
353
354namespace llvm {
355// Parse and return the header of an info section compile/type unit.
356Expected<InfoSectionUnitHeader> parseInfoSectionUnitHeader(StringRef Info) {
357 InfoSectionUnitHeader Header;
358 Error Err = Error::success();
359 uint64_t Offset = 0;
360 DWARFDataExtractor InfoData(Info, true, 0);
361 std::tie(args&: Header.Length, args&: Header.Format) =
362 InfoData.getInitialLength(Off: &Offset, Err: &Err);
363 if (Err)
364 return make_error<DWPError>(Args: "cannot parse compile unit length: " +
365 llvm::toString(E: std::move(Err)));
366
367 if (!InfoData.isValidOffset(offset: Offset + (Header.Length - 1))) {
368 return make_error<DWPError>(
369 Args: "compile unit exceeds .debug_info section range: " +
370 utostr(X: Offset + Header.Length) + " >= " + utostr(X: InfoData.size()));
371 }
372
373 Header.Version = InfoData.getU16(offset_ptr: &Offset, Err: &Err);
374 if (Err)
375 return make_error<DWPError>(Args: "cannot parse compile unit version: " +
376 llvm::toString(E: std::move(Err)));
377
378 uint64_t MinHeaderLength;
379 if (Header.Version >= 5) {
380 // Size: Version (2), UnitType (1), AddrSize (1), DebugAbbrevOffset (4),
381 // Signature (8)
382 MinHeaderLength = 16;
383 } else {
384 // Size: Version (2), DebugAbbrevOffset (4), AddrSize (1)
385 MinHeaderLength = 7;
386 }
387 if (Header.Length < MinHeaderLength) {
388 return make_error<DWPError>(Args: "unit length is too small: expected at least " +
389 utostr(X: MinHeaderLength) + " got " +
390 utostr(X: Header.Length) + ".");
391 }
392 if (Header.Version >= 5) {
393 Header.UnitType = InfoData.getU8(offset_ptr: &Offset);
394 Header.AddrSize = InfoData.getU8(offset_ptr: &Offset);
395 Header.DebugAbbrevOffset = InfoData.getU32(offset_ptr: &Offset);
396 Header.Signature = InfoData.getU64(offset_ptr: &Offset);
397 if (Header.UnitType == dwarf::DW_UT_split_type) {
398 // Type offset.
399 MinHeaderLength += 4;
400 if (Header.Length < MinHeaderLength)
401 return make_error<DWPError>(Args: "type unit is missing type offset");
402 InfoData.getU32(offset_ptr: &Offset);
403 }
404 } else {
405 // Note that, address_size and debug_abbrev_offset fields have switched
406 // places between dwarf version 4 and 5.
407 Header.DebugAbbrevOffset = InfoData.getU32(offset_ptr: &Offset);
408 Header.AddrSize = InfoData.getU8(offset_ptr: &Offset);
409 }
410
411 Header.HeaderSize = Offset;
412 return Header;
413}
414
415static void writeNewOffsetsTo(MCStreamer &Out, DataExtractor &Data,
416 DenseMap<uint64_t, uint32_t> &OffsetRemapping,
417 uint64_t &Offset, uint64_t &Size) {
418
419 while (Offset < Size) {
420 auto OldOffset = Data.getU32(offset_ptr: &Offset);
421 auto NewOffset = OffsetRemapping[OldOffset];
422 Out.emitIntValue(Value: NewOffset, Size: 4);
423 }
424}
425
426void writeStringsAndOffsets(MCStreamer &Out, DWPStringPool &Strings,
427 MCSection *StrOffsetSection,
428 StringRef CurStrSection,
429 StringRef CurStrOffsetSection, uint16_t Version) {
430 // Could possibly produce an error or warning if one of these was non-null but
431 // the other was null.
432 if (CurStrSection.empty() || CurStrOffsetSection.empty())
433 return;
434
435 DenseMap<uint64_t, uint32_t> OffsetRemapping;
436
437 DataExtractor Data(CurStrSection, true, 0);
438 uint64_t LocalOffset = 0;
439 uint64_t PrevOffset = 0;
440 while (const char *S = Data.getCStr(OffsetPtr: &LocalOffset)) {
441 OffsetRemapping[PrevOffset] =
442 Strings.getOffset(Str: S, Length: LocalOffset - PrevOffset);
443 PrevOffset = LocalOffset;
444 }
445
446 Data = DataExtractor(CurStrOffsetSection, true, 0);
447
448 Out.switchSection(Section: StrOffsetSection);
449
450 uint64_t Offset = 0;
451 uint64_t Size = CurStrOffsetSection.size();
452 if (Version > 4) {
453 while (Offset < Size) {
454 uint64_t HeaderSize = debugStrOffsetsHeaderSize(StrOffsetsData: Data, DwarfVersion: Version);
455 assert(HeaderSize <= Size - Offset &&
456 "StrOffsetSection size is less than its header");
457
458 uint64_t ContributionEnd = 0;
459 uint64_t ContributionSize = 0;
460 uint64_t HeaderLengthOffset = Offset;
461 if (HeaderSize == 8) {
462 ContributionSize = Data.getU32(offset_ptr: &HeaderLengthOffset);
463 } else if (HeaderSize == 16) {
464 HeaderLengthOffset += 4; // skip the dwarf64 marker
465 ContributionSize = Data.getU64(offset_ptr: &HeaderLengthOffset);
466 }
467 ContributionEnd = ContributionSize + HeaderLengthOffset;
468 Out.emitBytes(Data: Data.getBytes(OffsetPtr: &Offset, Length: HeaderSize));
469 writeNewOffsetsTo(Out, Data, OffsetRemapping, Offset, Size&: ContributionEnd);
470 }
471
472 } else {
473 writeNewOffsetsTo(Out, Data, OffsetRemapping, Offset, Size);
474 }
475}
476
477enum AccessField { Offset, Length };
478void writeIndexTable(MCStreamer &Out, ArrayRef<unsigned> ContributionOffsets,
479 const MapVector<uint64_t, UnitIndexEntry> &IndexEntries,
480 const AccessField &Field) {
481 for (const auto &E : IndexEntries)
482 for (size_t I = 0; I != std::size(E.second.Contributions); ++I)
483 if (ContributionOffsets[I])
484 Out.emitIntValue(Value: (Field == AccessField::Offset
485 ? E.second.Contributions[I].getOffset32()
486 : E.second.Contributions[I].getLength32()),
487 Size: 4);
488}
489
490void writeIndex(MCStreamer &Out, MCSection *Section,
491 ArrayRef<unsigned> ContributionOffsets,
492 const MapVector<uint64_t, UnitIndexEntry> &IndexEntries,
493 uint32_t IndexVersion) {
494 if (IndexEntries.empty())
495 return;
496
497 unsigned Columns = 0;
498 for (auto &C : ContributionOffsets)
499 if (C)
500 ++Columns;
501
502 std::vector<unsigned> Buckets(NextPowerOf2(A: 3 * IndexEntries.size() / 2));
503 uint64_t Mask = Buckets.size() - 1;
504 size_t I = 0;
505 for (const auto &P : IndexEntries) {
506 auto S = P.first;
507 auto H = S & Mask;
508 auto HP = ((S >> 32) & Mask) | 1;
509 while (Buckets[H]) {
510 assert(S != IndexEntries.begin()[Buckets[H] - 1].first &&
511 "Duplicate unit");
512 H = (H + HP) & Mask;
513 }
514 Buckets[H] = I + 1;
515 ++I;
516 }
517
518 Out.switchSection(Section);
519 Out.emitIntValue(Value: IndexVersion, Size: 4); // Version
520 Out.emitIntValue(Value: Columns, Size: 4); // Columns
521 Out.emitIntValue(Value: IndexEntries.size(), Size: 4); // Num Units
522 Out.emitIntValue(Value: Buckets.size(), Size: 4); // Num Buckets
523
524 // Write the signatures.
525 for (const auto &I : Buckets)
526 Out.emitIntValue(Value: I ? IndexEntries.begin()[I - 1].first : 0, Size: 8);
527
528 // Write the indexes.
529 for (const auto &I : Buckets)
530 Out.emitIntValue(Value: I, Size: 4);
531
532 // Write the column headers (which sections will appear in the table)
533 for (size_t I = 0; I != ContributionOffsets.size(); ++I)
534 if (ContributionOffsets[I])
535 Out.emitIntValue(Value: getOnDiskSectionId(Index: I), Size: 4);
536
537 // Write the offsets.
538 writeIndexTable(Out, ContributionOffsets, IndexEntries, Field: AccessField::Offset);
539
540 // Write the lengths.
541 writeIndexTable(Out, ContributionOffsets, IndexEntries, Field: AccessField::Length);
542}
543
544Error buildDuplicateError(const std::pair<uint64_t, UnitIndexEntry> &PrevE,
545 const CompileUnitIdentifiers &ID, StringRef DWPName) {
546 return make_error<DWPError>(
547 Args: std::string("duplicate DWO ID (") + utohexstr(X: PrevE.first) + ") in " +
548 buildDWODescription(Name: PrevE.second.Name, DWPName: PrevE.second.DWPName,
549 DWOName: PrevE.second.DWOName) +
550 " and " + buildDWODescription(Name: ID.Name, DWPName, DWOName: ID.DWOName));
551}
552
553Error handleSection(
554 const StringMap<std::pair<MCSection *, DWARFSectionKind>> &KnownSections,
555 const MCSection *StrSection, const MCSection *StrOffsetSection,
556 const MCSection *TypesSection, const MCSection *CUIndexSection,
557 const MCSection *TUIndexSection, const MCSection *InfoSection,
558 const SectionRef &Section, MCStreamer &Out,
559 std::deque<SmallString<32>> &UncompressedSections,
560 uint32_t (&ContributionOffsets)[8], UnitIndexEntry &CurEntry,
561 StringRef &CurStrSection, StringRef &CurStrOffsetSection,
562 std::vector<StringRef> &CurTypesSection,
563 std::vector<StringRef> &CurInfoSection, StringRef &AbbrevSection,
564 StringRef &CurCUIndexSection, StringRef &CurTUIndexSection,
565 std::vector<std::pair<DWARFSectionKind, uint32_t>> &SectionLength) {
566 if (Section.isBSS())
567 return Error::success();
568
569 if (Section.isVirtual())
570 return Error::success();
571
572 Expected<StringRef> NameOrErr = Section.getName();
573 if (!NameOrErr)
574 return NameOrErr.takeError();
575 StringRef Name = *NameOrErr;
576
577 Expected<StringRef> ContentsOrErr = Section.getContents();
578 if (!ContentsOrErr)
579 return ContentsOrErr.takeError();
580 StringRef Contents = *ContentsOrErr;
581
582 if (auto Err = handleCompressedSection(UncompressedSections, Sec: Section, Name,
583 Contents))
584 return Err;
585
586 Name = Name.substr(Start: Name.find_first_not_of(Chars: "._"));
587
588 auto SectionPair = KnownSections.find(Key: Name);
589 if (SectionPair == KnownSections.end())
590 return Error::success();
591
592 if (DWARFSectionKind Kind = SectionPair->second.second) {
593 if (Kind != DW_SECT_EXT_TYPES && Kind != DW_SECT_INFO) {
594 SectionLength.push_back(x: std::make_pair(x&: Kind, y: Contents.size()));
595 }
596
597 if (Kind == DW_SECT_ABBREV) {
598 AbbrevSection = Contents;
599 }
600 }
601
602 MCSection *OutSection = SectionPair->second.first;
603 if (OutSection == StrOffsetSection)
604 CurStrOffsetSection = Contents;
605 else if (OutSection == StrSection)
606 CurStrSection = Contents;
607 else if (OutSection == TypesSection)
608 CurTypesSection.push_back(x: Contents);
609 else if (OutSection == CUIndexSection)
610 CurCUIndexSection = Contents;
611 else if (OutSection == TUIndexSection)
612 CurTUIndexSection = Contents;
613 else if (OutSection == InfoSection)
614 CurInfoSection.push_back(x: Contents);
615 else {
616 Out.switchSection(Section: OutSection);
617 Out.emitBytes(Data: Contents);
618 }
619 return Error::success();
620}
621
622Error write(MCStreamer &Out, ArrayRef<std::string> Inputs,
623 OnCuIndexOverflow OverflowOptValue) {
624 const auto &MCOFI = *Out.getContext().getObjectFileInfo();
625 MCSection *const StrSection = MCOFI.getDwarfStrDWOSection();
626 MCSection *const StrOffsetSection = MCOFI.getDwarfStrOffDWOSection();
627 MCSection *const TypesSection = MCOFI.getDwarfTypesDWOSection();
628 MCSection *const CUIndexSection = MCOFI.getDwarfCUIndexSection();
629 MCSection *const TUIndexSection = MCOFI.getDwarfTUIndexSection();
630 MCSection *const InfoSection = MCOFI.getDwarfInfoDWOSection();
631 const StringMap<std::pair<MCSection *, DWARFSectionKind>> KnownSections = {
632 {"debug_info.dwo", {InfoSection, DW_SECT_INFO}},
633 {"debug_types.dwo", {MCOFI.getDwarfTypesDWOSection(), DW_SECT_EXT_TYPES}},
634 {"debug_str_offsets.dwo", {StrOffsetSection, DW_SECT_STR_OFFSETS}},
635 {"debug_str.dwo", {StrSection, static_cast<DWARFSectionKind>(0)}},
636 {"debug_loc.dwo", {MCOFI.getDwarfLocDWOSection(), DW_SECT_EXT_LOC}},
637 {"debug_line.dwo", {MCOFI.getDwarfLineDWOSection(), DW_SECT_LINE}},
638 {"debug_macro.dwo", {MCOFI.getDwarfMacroDWOSection(), DW_SECT_MACRO}},
639 {"debug_abbrev.dwo", {MCOFI.getDwarfAbbrevDWOSection(), DW_SECT_ABBREV}},
640 {"debug_loclists.dwo",
641 {MCOFI.getDwarfLoclistsDWOSection(), DW_SECT_LOCLISTS}},
642 {"debug_rnglists.dwo",
643 {MCOFI.getDwarfRnglistsDWOSection(), DW_SECT_RNGLISTS}},
644 {"debug_cu_index", {CUIndexSection, static_cast<DWARFSectionKind>(0)}},
645 {"debug_tu_index", {TUIndexSection, static_cast<DWARFSectionKind>(0)}}};
646
647 MapVector<uint64_t, UnitIndexEntry> IndexEntries;
648 MapVector<uint64_t, UnitIndexEntry> TypeIndexEntries;
649
650 uint32_t ContributionOffsets[8] = {};
651 uint16_t Version = 0;
652 uint32_t IndexVersion = 0;
653 bool AnySectionOverflow = false;
654
655 DWPStringPool Strings(Out, StrSection);
656
657 SmallVector<OwningBinary<object::ObjectFile>, 128> Objects;
658 Objects.reserve(N: Inputs.size());
659
660 std::deque<SmallString<32>> UncompressedSections;
661
662 for (const auto &Input : Inputs) {
663 auto ErrOrObj = object::ObjectFile::createObjectFile(ObjectPath: Input);
664 if (!ErrOrObj) {
665 return handleErrors(E: ErrOrObj.takeError(),
666 Hs: [&](std::unique_ptr<ECError> EC) -> Error {
667 return createFileError(F: Input, E: Error(std::move(EC)));
668 });
669 }
670
671 auto &Obj = *ErrOrObj->getBinary();
672 Objects.push_back(Elt: std::move(*ErrOrObj));
673
674 UnitIndexEntry CurEntry = {};
675
676 StringRef CurStrSection;
677 StringRef CurStrOffsetSection;
678 std::vector<StringRef> CurTypesSection;
679 std::vector<StringRef> CurInfoSection;
680 StringRef AbbrevSection;
681 StringRef CurCUIndexSection;
682 StringRef CurTUIndexSection;
683
684 // This maps each section contained in this file to its length.
685 // This information is later on used to calculate the contributions,
686 // i.e. offset and length, of each compile/type unit to a section.
687 std::vector<std::pair<DWARFSectionKind, uint32_t>> SectionLength;
688
689 for (const auto &Section : Obj.sections())
690 if (auto Err = handleSection(
691 KnownSections, StrSection, StrOffsetSection, TypesSection,
692 CUIndexSection, TUIndexSection, InfoSection, Section, Out,
693 UncompressedSections, ContributionOffsets, CurEntry,
694 CurStrSection, CurStrOffsetSection, CurTypesSection,
695 CurInfoSection, AbbrevSection, CurCUIndexSection,
696 CurTUIndexSection, SectionLength))
697 return Err;
698
699 if (CurInfoSection.empty())
700 continue;
701
702 Expected<InfoSectionUnitHeader> HeaderOrErr =
703 parseInfoSectionUnitHeader(Info: CurInfoSection.front());
704 if (!HeaderOrErr)
705 return HeaderOrErr.takeError();
706 InfoSectionUnitHeader &Header = *HeaderOrErr;
707
708 if (Version == 0) {
709 Version = Header.Version;
710 IndexVersion = Version < 5 ? 2 : 5;
711 } else if (Version != Header.Version) {
712 return make_error<DWPError>(Args: "incompatible DWARF compile unit versions.");
713 }
714
715 writeStringsAndOffsets(Out, Strings, StrOffsetSection, CurStrSection,
716 CurStrOffsetSection, Version: Header.Version);
717
718 for (auto Pair : SectionLength) {
719 auto Index = getContributionIndex(Kind: Pair.first, IndexVersion);
720 CurEntry.Contributions[Index].setOffset(ContributionOffsets[Index]);
721 CurEntry.Contributions[Index].setLength(Pair.second);
722 uint32_t OldOffset = ContributionOffsets[Index];
723 ContributionOffsets[Index] += CurEntry.Contributions[Index].getLength32();
724 if (OldOffset > ContributionOffsets[Index]) {
725 uint32_t SectionIndex = 0;
726 for (auto &Section : Obj.sections()) {
727 if (SectionIndex == Index) {
728 if (Error Err = sectionOverflowErrorOrWarning(
729 PrevOffset: OldOffset, OverflowedOffset: ContributionOffsets[Index], SectionName: *Section.getName(),
730 OverflowOptValue, AnySectionOverflow))
731 return Err;
732 }
733 ++SectionIndex;
734 }
735 if (AnySectionOverflow)
736 break;
737 }
738 }
739
740 uint32_t &InfoSectionOffset =
741 ContributionOffsets[getContributionIndex(Kind: DW_SECT_INFO, IndexVersion)];
742 if (CurCUIndexSection.empty()) {
743 bool FoundCUUnit = false;
744 Out.switchSection(Section: InfoSection);
745 for (StringRef Info : CurInfoSection) {
746 uint64_t UnitOffset = 0;
747 while (Info.size() > UnitOffset) {
748 Expected<InfoSectionUnitHeader> HeaderOrError =
749 parseInfoSectionUnitHeader(Info: Info.substr(Start: UnitOffset, N: Info.size()));
750 if (!HeaderOrError)
751 return HeaderOrError.takeError();
752 InfoSectionUnitHeader &Header = *HeaderOrError;
753
754 UnitIndexEntry Entry = CurEntry;
755 auto &C = Entry.Contributions[getContributionIndex(Kind: DW_SECT_INFO,
756 IndexVersion)];
757 C.setOffset(InfoSectionOffset);
758 C.setLength(Header.Length + 4);
759
760 if (std::numeric_limits<uint32_t>::max() - InfoSectionOffset <
761 C.getLength32()) {
762 if (Error Err = sectionOverflowErrorOrWarning(
763 PrevOffset: InfoSectionOffset, OverflowedOffset: InfoSectionOffset + C.getLength32(),
764 SectionName: "debug_info", OverflowOptValue, AnySectionOverflow))
765 return Err;
766 if (AnySectionOverflow) {
767 if (Header.Version < 5 ||
768 Header.UnitType == dwarf::DW_UT_split_compile)
769 FoundCUUnit = true;
770 break;
771 }
772 }
773
774 UnitOffset += C.getLength32();
775 if (Header.Version < 5 ||
776 Header.UnitType == dwarf::DW_UT_split_compile) {
777 Expected<CompileUnitIdentifiers> EID = getCUIdentifiers(
778 Header, Abbrev: AbbrevSection,
779 Info: Info.substr(Start: UnitOffset - C.getLength32(), N: C.getLength32()),
780 StrOffsets: CurStrOffsetSection, Str: CurStrSection);
781
782 if (!EID)
783 return createFileError(F: Input, E: EID.takeError());
784 const auto &ID = *EID;
785 auto P = IndexEntries.insert(KV: std::make_pair(x: ID.Signature, y&: Entry));
786 if (!P.second)
787 return buildDuplicateError(PrevE: *P.first, ID, DWPName: "");
788 P.first->second.Name = ID.Name;
789 P.first->second.DWOName = ID.DWOName;
790
791 FoundCUUnit = true;
792 } else if (Header.UnitType == dwarf::DW_UT_split_type) {
793 auto P = TypeIndexEntries.insert(
794 KV: std::make_pair(x&: *Header.Signature, y&: Entry));
795 if (!P.second)
796 continue;
797 }
798 Out.emitBytes(
799 Data: Info.substr(Start: UnitOffset - C.getLength32(), N: C.getLength32()));
800 InfoSectionOffset += C.getLength32();
801 }
802 if (AnySectionOverflow)
803 break;
804 }
805
806 if (!FoundCUUnit)
807 return make_error<DWPError>(Args: "no compile unit found in file: " + Input);
808
809 if (IndexVersion == 2) {
810 // Add types from the .debug_types section from DWARF < 5.
811 if (Error Err = addAllTypesFromTypesSection(
812 Out, TypeIndexEntries, OutputTypes: TypesSection, TypesSections: CurTypesSection, CUEntry: CurEntry,
813 TypesOffset&: ContributionOffsets[getContributionIndex(Kind: DW_SECT_EXT_TYPES, IndexVersion: 2)],
814 OverflowOptValue, AnySectionOverflow))
815 return Err;
816 }
817 if (AnySectionOverflow)
818 break;
819 continue;
820 }
821
822 if (CurInfoSection.size() != 1)
823 return make_error<DWPError>(Args: "expected exactly one occurrence of a debug "
824 "info section in a .dwp file");
825 StringRef DwpSingleInfoSection = CurInfoSection.front();
826
827 DWARFUnitIndex CUIndex(DW_SECT_INFO);
828 DataExtractor CUIndexData(CurCUIndexSection, Obj.isLittleEndian(), 0);
829 if (!CUIndex.parse(IndexData: CUIndexData))
830 return make_error<DWPError>(Args: "failed to parse cu_index");
831 if (CUIndex.getVersion() != IndexVersion)
832 return make_error<DWPError>(Args: "incompatible cu_index versions, found " +
833 utostr(X: CUIndex.getVersion()) +
834 " and expecting " + utostr(X: IndexVersion));
835
836 Out.switchSection(Section: InfoSection);
837 for (const DWARFUnitIndex::Entry &E : CUIndex.getRows()) {
838 auto *I = E.getContributions();
839 if (!I)
840 continue;
841 auto P = IndexEntries.insert(KV: std::make_pair(x: E.getSignature(), y&: CurEntry));
842 StringRef CUInfoSection =
843 getSubsection(Section: DwpSingleInfoSection, Entry: E, Kind: DW_SECT_INFO);
844 Expected<InfoSectionUnitHeader> HeaderOrError =
845 parseInfoSectionUnitHeader(Info: CUInfoSection);
846 if (!HeaderOrError)
847 return HeaderOrError.takeError();
848 InfoSectionUnitHeader &Header = *HeaderOrError;
849
850 Expected<CompileUnitIdentifiers> EID = getCUIdentifiers(
851 Header, Abbrev: getSubsection(Section: AbbrevSection, Entry: E, Kind: DW_SECT_ABBREV),
852 Info: CUInfoSection,
853 StrOffsets: getSubsection(Section: CurStrOffsetSection, Entry: E, Kind: DW_SECT_STR_OFFSETS),
854 Str: CurStrSection);
855 if (!EID)
856 return createFileError(F: Input, E: EID.takeError());
857 const auto &ID = *EID;
858 if (!P.second)
859 return buildDuplicateError(PrevE: *P.first, ID, DWPName: Input);
860 auto &NewEntry = P.first->second;
861 NewEntry.Name = ID.Name;
862 NewEntry.DWOName = ID.DWOName;
863 NewEntry.DWPName = Input;
864 for (auto Kind : CUIndex.getColumnKinds()) {
865 if (!isSupportedSectionKind(Kind))
866 continue;
867 auto &C =
868 NewEntry.Contributions[getContributionIndex(Kind, IndexVersion)];
869 C.setOffset(C.getOffset() + I->getOffset());
870 C.setLength(I->getLength());
871 ++I;
872 }
873 unsigned Index = getContributionIndex(Kind: DW_SECT_INFO, IndexVersion);
874 auto &C = NewEntry.Contributions[Index];
875 Out.emitBytes(Data: CUInfoSection);
876 C.setOffset(InfoSectionOffset);
877 InfoSectionOffset += C.getLength32();
878 }
879
880 if (!CurTUIndexSection.empty()) {
881 llvm::DWARFSectionKind TUSectionKind;
882 MCSection *OutSection;
883 StringRef TypeInputSection;
884 // Write type units into debug info section for DWARFv5.
885 if (Version >= 5) {
886 TUSectionKind = DW_SECT_INFO;
887 OutSection = InfoSection;
888 TypeInputSection = DwpSingleInfoSection;
889 } else {
890 // Write type units into debug types section for DWARF < 5.
891 if (CurTypesSection.size() != 1)
892 return make_error<DWPError>(
893 Args: "multiple type unit sections in .dwp file");
894
895 TUSectionKind = DW_SECT_EXT_TYPES;
896 OutSection = TypesSection;
897 TypeInputSection = CurTypesSection.front();
898 }
899
900 DWARFUnitIndex TUIndex(TUSectionKind);
901 DataExtractor TUIndexData(CurTUIndexSection, Obj.isLittleEndian(), 0);
902 if (!TUIndex.parse(IndexData: TUIndexData))
903 return make_error<DWPError>(Args: "failed to parse tu_index");
904 if (TUIndex.getVersion() != IndexVersion)
905 return make_error<DWPError>(Args: "incompatible tu_index versions, found " +
906 utostr(X: TUIndex.getVersion()) +
907 " and expecting " + utostr(X: IndexVersion));
908
909 unsigned TypesContributionIndex =
910 getContributionIndex(Kind: TUSectionKind, IndexVersion);
911 if (Error Err = addAllTypesFromDWP(
912 Out, TypeIndexEntries, TUIndex, OutputTypes: OutSection, Types: TypeInputSection,
913 TUEntry: CurEntry, TypesOffset&: ContributionOffsets[TypesContributionIndex],
914 TypesContributionIndex, OverflowOptValue, AnySectionOverflow))
915 return Err;
916 }
917 if (AnySectionOverflow)
918 break;
919 }
920
921 if (Version < 5) {
922 // Lie about there being no info contributions so the TU index only includes
923 // the type unit contribution for DWARF < 5. In DWARFv5 the TU index has a
924 // contribution to the info section, so we do not want to lie about it.
925 ContributionOffsets[0] = 0;
926 }
927 writeIndex(Out, Section: MCOFI.getDwarfTUIndexSection(), ContributionOffsets,
928 IndexEntries: TypeIndexEntries, IndexVersion);
929
930 if (Version < 5) {
931 // Lie about the type contribution for DWARF < 5. In DWARFv5 the type
932 // section does not exist, so no need to do anything about this.
933 ContributionOffsets[getContributionIndex(Kind: DW_SECT_EXT_TYPES, IndexVersion: 2)] = 0;
934 // Unlie about the info contribution
935 ContributionOffsets[0] = 1;
936 }
937
938 writeIndex(Out, Section: MCOFI.getDwarfCUIndexSection(), ContributionOffsets,
939 IndexEntries, IndexVersion);
940
941 return Error::success();
942}
943} // namespace llvm
944