1//===- DWARFAcceleratorTable.cpp ------------------------------------------===//
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#include "llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h"
10
11#include "llvm/ADT/SmallVector.h"
12#include "llvm/BinaryFormat/Dwarf.h"
13#include "llvm/Support/Compiler.h"
14#include "llvm/Support/DJB.h"
15#include "llvm/Support/Errc.h"
16#include "llvm/Support/Format.h"
17#include "llvm/Support/FormatVariadic.h"
18#include "llvm/Support/ScopedPrinter.h"
19#include "llvm/Support/raw_ostream.h"
20#include <cstddef>
21#include <cstdint>
22#include <utility>
23
24using namespace llvm;
25
26namespace {
27struct Atom {
28 unsigned Value;
29};
30
31static raw_ostream &operator<<(raw_ostream &OS, const Atom &A) {
32 StringRef Str = dwarf::AtomTypeString(Atom: A.Value);
33 if (!Str.empty())
34 return OS << Str;
35 return OS << "DW_ATOM_unknown_" << format(Fmt: "%x", Vals: A.Value);
36}
37} // namespace
38
39static Atom formatAtom(unsigned Atom) { return {.Value: Atom}; }
40
41DWARFAcceleratorTable::~DWARFAcceleratorTable() = default;
42
43Error AppleAcceleratorTable::extract() {
44 uint64_t Offset = 0;
45
46 // Check that we can at least read the header.
47 if (!AccelSection.isValidOffset(offsetof(Header, HeaderDataLength) + 4))
48 return createStringError(EC: errc::illegal_byte_sequence,
49 S: "Section too small: cannot read header.");
50
51 Hdr.Magic = AccelSection.getU32(offset_ptr: &Offset);
52 Hdr.Version = AccelSection.getU16(offset_ptr: &Offset);
53 Hdr.HashFunction = AccelSection.getU16(offset_ptr: &Offset);
54 Hdr.BucketCount = AccelSection.getU32(offset_ptr: &Offset);
55 Hdr.HashCount = AccelSection.getU32(offset_ptr: &Offset);
56 Hdr.HeaderDataLength = AccelSection.getU32(offset_ptr: &Offset);
57 FormParams = {.Version: Hdr.Version, .AddrSize: 0, .Format: dwarf::DwarfFormat::DWARF32};
58
59 // Check that we can read all the hashes and offsets from the
60 // section (see SourceLevelDebugging.rst for the structure of the index).
61 if (!AccelSection.isValidOffset(offset: getIthBucketBase(I: Hdr.BucketCount - 1)))
62 return createStringError(
63 EC: errc::illegal_byte_sequence,
64 S: "Section too small: cannot read buckets and hashes.");
65
66 HdrData.DIEOffsetBase = AccelSection.getU32(offset_ptr: &Offset);
67 uint32_t NumAtoms = AccelSection.getU32(offset_ptr: &Offset);
68
69 HashDataEntryLength = 0;
70 auto MakeUnsupportedFormError = [](dwarf::Form Form) {
71 return createStringError(EC: errc::not_supported,
72 S: "Unsupported form:" +
73 dwarf::FormEncodingString(Encoding: Form));
74 };
75
76 for (unsigned i = 0; i < NumAtoms; ++i) {
77 uint16_t AtomType = AccelSection.getU16(offset_ptr: &Offset);
78 auto AtomForm = static_cast<dwarf::Form>(AccelSection.getU16(offset_ptr: &Offset));
79 HdrData.Atoms.push_back(Elt: std::make_pair(x&: AtomType, y&: AtomForm));
80
81 std::optional<uint8_t> FormSize =
82 dwarf::getFixedFormByteSize(Form: AtomForm, Params: FormParams);
83 if (!FormSize)
84 return MakeUnsupportedFormError(AtomForm);
85 HashDataEntryLength += *FormSize;
86 }
87
88 IsValid = true;
89 return Error::success();
90}
91
92uint32_t AppleAcceleratorTable::getNumBuckets() const {
93 return Hdr.BucketCount;
94}
95uint32_t AppleAcceleratorTable::getNumHashes() const { return Hdr.HashCount; }
96uint32_t AppleAcceleratorTable::getSizeHdr() const { return sizeof(Hdr); }
97uint32_t AppleAcceleratorTable::getHeaderDataLength() const {
98 return Hdr.HeaderDataLength;
99}
100
101ArrayRef<std::pair<AppleAcceleratorTable::HeaderData::AtomType,
102 AppleAcceleratorTable::HeaderData::Form>>
103AppleAcceleratorTable::getAtomsDesc() {
104 return HdrData.Atoms;
105}
106
107bool AppleAcceleratorTable::validateForms() {
108 for (auto Atom : getAtomsDesc()) {
109 DWARFFormValue FormValue(Atom.second);
110 switch (Atom.first) {
111 case dwarf::DW_ATOM_die_offset:
112 case dwarf::DW_ATOM_die_tag:
113 case dwarf::DW_ATOM_type_flags:
114 if ((!FormValue.isFormClass(FC: DWARFFormValue::FC_Constant) &&
115 !FormValue.isFormClass(FC: DWARFFormValue::FC_Flag)) ||
116 FormValue.getForm() == dwarf::DW_FORM_sdata)
117 return false;
118 break;
119 default:
120 break;
121 }
122 }
123 return true;
124}
125
126std::pair<uint64_t, dwarf::Tag>
127AppleAcceleratorTable::readAtoms(uint64_t *HashDataOffset) {
128 uint64_t DieOffset = dwarf::DW_INVALID_OFFSET;
129 dwarf::Tag DieTag = dwarf::DW_TAG_null;
130
131 for (auto Atom : getAtomsDesc()) {
132 DWARFFormValue FormValue(Atom.second);
133 FormValue.extractValue(Data: AccelSection, OffsetPtr: HashDataOffset, FormParams);
134 switch (Atom.first) {
135 case dwarf::DW_ATOM_die_offset:
136 DieOffset = *FormValue.getAsUnsignedConstant();
137 break;
138 case dwarf::DW_ATOM_die_tag:
139 DieTag = (dwarf::Tag)*FormValue.getAsUnsignedConstant();
140 break;
141 default:
142 break;
143 }
144 }
145 return {DieOffset, DieTag};
146}
147
148void AppleAcceleratorTable::Header::dump(ScopedPrinter &W) const {
149 DictScope HeaderScope(W, "Header");
150 W.printHex(Label: "Magic", Value: Magic);
151 W.printHex(Label: "Version", Value: Version);
152 W.printHex(Label: "Hash function", Value: HashFunction);
153 W.printNumber(Label: "Bucket count", Value: BucketCount);
154 W.printNumber(Label: "Hashes count", Value: HashCount);
155 W.printNumber(Label: "HeaderData length", Value: HeaderDataLength);
156}
157
158std::optional<uint64_t> AppleAcceleratorTable::HeaderData::extractOffset(
159 std::optional<DWARFFormValue> Value) const {
160 if (!Value)
161 return std::nullopt;
162
163 switch (Value->getForm()) {
164 case dwarf::DW_FORM_ref1:
165 case dwarf::DW_FORM_ref2:
166 case dwarf::DW_FORM_ref4:
167 case dwarf::DW_FORM_ref8:
168 case dwarf::DW_FORM_ref_udata:
169 return Value->getRawUValue() + DIEOffsetBase;
170 default:
171 return Value->getAsSectionOffset();
172 }
173}
174
175bool AppleAcceleratorTable::dumpName(ScopedPrinter &W,
176 SmallVectorImpl<DWARFFormValue> &AtomForms,
177 uint64_t *DataOffset) const {
178 uint64_t NameOffset = *DataOffset;
179 if (!AccelSection.isValidOffsetForDataOfSize(offset: *DataOffset, length: 4)) {
180 W.printString(Value: "Incorrectly terminated list.");
181 return false;
182 }
183 uint64_t StringOffset = AccelSection.getRelocatedValue(Size: 4, Off: DataOffset);
184 if (!StringOffset)
185 return false; // End of list
186
187 DictScope NameScope(W, ("Name@0x" + Twine::utohexstr(Val: NameOffset)).str());
188 W.startLine() << format(Fmt: "String: 0x%08" PRIx64, Vals: StringOffset);
189 W.getOStream() << " \"" << StringSection.getCStr(OffsetPtr: &StringOffset) << "\"\n";
190
191 unsigned NumData = AccelSection.getU32(offset_ptr: DataOffset);
192 for (unsigned Data = 0; Data < NumData; ++Data) {
193 ListScope DataScope(W, ("Data " + Twine(Data)).str());
194 unsigned i = 0;
195 for (auto &Atom : AtomForms) {
196 W.startLine() << format(Fmt: "Atom[%d]: ", Vals: i);
197 if (Atom.extractValue(Data: AccelSection, OffsetPtr: DataOffset, FormParams)) {
198 Atom.dump(OS&: W.getOStream());
199 if (std::optional<uint64_t> Val = Atom.getAsUnsignedConstant()) {
200 StringRef Str = dwarf::AtomValueString(Atom: HdrData.Atoms[i].first, Val: *Val);
201 if (!Str.empty())
202 W.getOStream() << " (" << Str << ")";
203 }
204 } else
205 W.getOStream() << "Error extracting the value";
206 W.getOStream() << "\n";
207 i++;
208 }
209 }
210 return true; // more entries follow
211}
212
213LLVM_DUMP_METHOD void AppleAcceleratorTable::dump(raw_ostream &OS) const {
214 if (!IsValid)
215 return;
216
217 ScopedPrinter W(OS);
218
219 Hdr.dump(W);
220
221 W.printNumber(Label: "DIE offset base", Value: HdrData.DIEOffsetBase);
222 W.printNumber(Label: "Number of atoms", Value: uint64_t(HdrData.Atoms.size()));
223 W.printNumber(Label: "Size of each hash data entry", Value: getHashDataEntryLength());
224 SmallVector<DWARFFormValue, 3> AtomForms;
225 {
226 ListScope AtomsScope(W, "Atoms");
227 unsigned i = 0;
228 for (const auto &Atom : HdrData.Atoms) {
229 DictScope AtomScope(W, ("Atom " + Twine(i++)).str());
230 W.startLine() << "Type: " << formatAtom(Atom: Atom.first) << '\n';
231 W.startLine() << "Form: " << formatv(Fmt: "{0}", Vals: Atom.second) << '\n';
232 AtomForms.push_back(Elt: DWARFFormValue(Atom.second));
233 }
234 }
235
236 // Now go through the actual tables and dump them.
237 uint64_t Offset = sizeof(Hdr) + Hdr.HeaderDataLength;
238 uint64_t HashesBase = Offset + Hdr.BucketCount * 4;
239 uint64_t OffsetsBase = HashesBase + Hdr.HashCount * 4;
240
241 for (unsigned Bucket = 0; Bucket < Hdr.BucketCount; ++Bucket) {
242 unsigned Index = AccelSection.getU32(offset_ptr: &Offset);
243
244 ListScope BucketScope(W, ("Bucket " + Twine(Bucket)).str());
245 if (Index == UINT32_MAX) {
246 W.printString(Value: "EMPTY");
247 continue;
248 }
249
250 for (unsigned HashIdx = Index; HashIdx < Hdr.HashCount; ++HashIdx) {
251 uint64_t HashOffset = HashesBase + HashIdx*4;
252 uint64_t OffsetsOffset = OffsetsBase + HashIdx*4;
253 uint32_t Hash = AccelSection.getU32(offset_ptr: &HashOffset);
254
255 if (Hash % Hdr.BucketCount != Bucket)
256 break;
257
258 uint64_t DataOffset = AccelSection.getU32(offset_ptr: &OffsetsOffset);
259 ListScope HashScope(W, ("Hash 0x" + Twine::utohexstr(Val: Hash)).str());
260 if (!AccelSection.isValidOffset(offset: DataOffset)) {
261 W.printString(Value: "Invalid section offset");
262 continue;
263 }
264 while (dumpName(W, AtomForms, DataOffset: &DataOffset))
265 /*empty*/;
266 }
267 }
268}
269
270AppleAcceleratorTable::Entry::Entry(const AppleAcceleratorTable &Table)
271 : Table(Table) {
272 Values.reserve(N: Table.HdrData.Atoms.size());
273 for (const auto &Atom : Table.HdrData.Atoms)
274 Values.push_back(Elt: DWARFFormValue(Atom.second));
275}
276
277void AppleAcceleratorTable::Entry::extract(uint64_t *Offset) {
278 for (auto &FormValue : Values)
279 FormValue.extractValue(Data: Table.AccelSection, OffsetPtr: Offset, FormParams: Table.FormParams);
280}
281
282std::optional<DWARFFormValue>
283AppleAcceleratorTable::Entry::lookup(HeaderData::AtomType AtomToFind) const {
284 for (auto [Atom, FormValue] : zip_equal(t: Table.HdrData.Atoms, u: Values))
285 if (Atom.first == AtomToFind)
286 return FormValue;
287 return std::nullopt;
288}
289
290std::optional<uint64_t>
291AppleAcceleratorTable::Entry::getDIESectionOffset() const {
292 return Table.HdrData.extractOffset(Value: lookup(AtomToFind: dwarf::DW_ATOM_die_offset));
293}
294
295std::optional<uint64_t> AppleAcceleratorTable::Entry::getCUOffset() const {
296 return Table.HdrData.extractOffset(Value: lookup(AtomToFind: dwarf::DW_ATOM_cu_offset));
297}
298
299std::optional<dwarf::Tag> AppleAcceleratorTable::Entry::getTag() const {
300 std::optional<DWARFFormValue> Tag = lookup(AtomToFind: dwarf::DW_ATOM_die_tag);
301 if (!Tag)
302 return std::nullopt;
303 if (std::optional<uint64_t> Value = Tag->getAsUnsignedConstant())
304 return dwarf::Tag(*Value);
305 return std::nullopt;
306}
307
308AppleAcceleratorTable::SameNameIterator::SameNameIterator(
309 const AppleAcceleratorTable &AccelTable, uint64_t DataOffset)
310 : Current(AccelTable), Offset(DataOffset) {}
311
312void AppleAcceleratorTable::Iterator::prepareNextEntryOrEnd() {
313 if (NumEntriesToCome == 0)
314 prepareNextStringOrEnd();
315 if (isEnd())
316 return;
317 uint64_t OffsetCopy = Offset;
318 Current.BaseEntry.extract(Offset: &OffsetCopy);
319 NumEntriesToCome--;
320 Offset += getTable().getHashDataEntryLength();
321}
322
323void AppleAcceleratorTable::Iterator::prepareNextStringOrEnd() {
324 std::optional<uint32_t> StrOffset = getTable().readStringOffsetAt(Offset);
325 if (!StrOffset)
326 return setToEnd();
327
328 // A zero denotes the end of the collision list. Read the next string
329 // again.
330 if (*StrOffset == 0)
331 return prepareNextStringOrEnd();
332 Current.StrOffset = *StrOffset;
333
334 std::optional<uint32_t> MaybeNumEntries = getTable().readU32FromAccel(Offset);
335 if (!MaybeNumEntries || *MaybeNumEntries == 0)
336 return setToEnd();
337 NumEntriesToCome = *MaybeNumEntries;
338}
339
340AppleAcceleratorTable::Iterator::Iterator(const AppleAcceleratorTable &Table,
341 bool SetEnd)
342 : Current(Table), Offset(Table.getEntriesBase()), NumEntriesToCome(0) {
343 if (SetEnd)
344 setToEnd();
345 else
346 prepareNextEntryOrEnd();
347}
348
349iterator_range<AppleAcceleratorTable::SameNameIterator>
350AppleAcceleratorTable::equal_range(StringRef Key) const {
351 const auto EmptyRange =
352 make_range(x: SameNameIterator(*this, 0), y: SameNameIterator(*this, 0));
353 if (!IsValid)
354 return EmptyRange;
355
356 // Find the bucket.
357 uint32_t SearchHash = djbHash(Buffer: Key);
358 uint32_t BucketIdx = hashToBucketIdx(Hash: SearchHash);
359 std::optional<uint32_t> HashIdx = idxOfHashInBucket(HashToFind: SearchHash, BucketIdx);
360 if (!HashIdx)
361 return EmptyRange;
362
363 std::optional<uint64_t> MaybeDataOffset = readIthOffset(I: *HashIdx);
364 if (!MaybeDataOffset)
365 return EmptyRange;
366
367 uint64_t DataOffset = *MaybeDataOffset;
368 if (DataOffset >= AccelSection.size())
369 return EmptyRange;
370
371 std::optional<uint32_t> StrOffset = readStringOffsetAt(Offset&: DataOffset);
372 // Valid input and still have strings in this hash.
373 while (StrOffset && *StrOffset) {
374 std::optional<StringRef> MaybeStr = readStringFromStrSection(StringSectionOffset: *StrOffset);
375 std::optional<uint32_t> NumEntries = this->readU32FromAccel(Offset&: DataOffset);
376 if (!MaybeStr || !NumEntries)
377 return EmptyRange;
378 uint64_t EndOffset = DataOffset + *NumEntries * getHashDataEntryLength();
379 if (Key == *MaybeStr)
380 return make_range(x: {*this, DataOffset},
381 y: SameNameIterator{*this, EndOffset});
382 DataOffset = EndOffset;
383 StrOffset = readStringOffsetAt(Offset&: DataOffset);
384 }
385
386 return EmptyRange;
387}
388
389std::optional<uint32_t>
390AppleAcceleratorTable::idxOfHashInBucket(uint32_t HashToFind,
391 uint32_t BucketIdx) const {
392 std::optional<uint32_t> HashStartIdx = readIthBucket(I: BucketIdx);
393 if (!HashStartIdx)
394 return std::nullopt;
395
396 for (uint32_t HashIdx = *HashStartIdx; HashIdx < getNumHashes(); HashIdx++) {
397 std::optional<uint32_t> MaybeHash = readIthHash(I: HashIdx);
398 if (!MaybeHash || !wouldHashBeInBucket(Hash: *MaybeHash, BucketIdx))
399 break;
400 if (*MaybeHash == HashToFind)
401 return HashIdx;
402 }
403 return std::nullopt;
404}
405
406std::optional<StringRef> AppleAcceleratorTable::readStringFromStrSection(
407 uint64_t StringSectionOffset) const {
408 Error E = Error::success();
409 StringRef Str = StringSection.getCStrRef(OffsetPtr: &StringSectionOffset, Err: &E);
410 if (E) {
411 consumeError(Err: std::move(E));
412 return std::nullopt;
413 }
414 return Str;
415}
416
417std::optional<uint32_t>
418AppleAcceleratorTable::readU32FromAccel(uint64_t &Offset,
419 bool UseRelocation) const {
420 Error E = Error::success();
421 uint32_t Data = UseRelocation
422 ? AccelSection.getRelocatedValue(Size: 4, Off: &Offset, SectionIndex: nullptr, Err: &E)
423 : AccelSection.getU32(offset_ptr: &Offset, Err: &E);
424 if (E) {
425 consumeError(Err: std::move(E));
426 return std::nullopt;
427 }
428 return Data;
429}
430
431void DWARFDebugNames::Header::dump(ScopedPrinter &W) const {
432 DictScope HeaderScope(W, "Header");
433 W.printHex(Label: "Length", Value: UnitLength);
434 W.printString(Label: "Format", Value: dwarf::FormatString(Format));
435 W.printNumber(Label: "Version", Value: Version);
436 W.printNumber(Label: "CU count", Value: CompUnitCount);
437 W.printNumber(Label: "Local TU count", Value: LocalTypeUnitCount);
438 W.printNumber(Label: "Foreign TU count", Value: ForeignTypeUnitCount);
439 W.printNumber(Label: "Bucket count", Value: BucketCount);
440 W.printNumber(Label: "Name count", Value: NameCount);
441 W.printHex(Label: "Abbreviations table size", Value: AbbrevTableSize);
442 W.startLine() << "Augmentation: '" << AugmentationString << "'\n";
443}
444
445Error DWARFDebugNames::Header::extract(const DWARFDataExtractor &AS,
446 uint64_t *Offset) {
447 auto HeaderError = [Offset = *Offset](Error E) {
448 return createStringError(EC: errc::illegal_byte_sequence,
449 Fmt: "parsing .debug_names header at 0x%" PRIx64 ": %s",
450 Vals: Offset, Vals: toString(E: std::move(E)).c_str());
451 };
452
453 DataExtractor::Cursor C(*Offset);
454 std::tie(args&: UnitLength, args&: Format) = AS.getInitialLength(C);
455
456 Version = AS.getU16(C);
457 AS.skip(C, Length: 2); // padding
458 CompUnitCount = AS.getU32(C);
459 LocalTypeUnitCount = AS.getU32(C);
460 ForeignTypeUnitCount = AS.getU32(C);
461 BucketCount = AS.getU32(C);
462 NameCount = AS.getU32(C);
463 AbbrevTableSize = AS.getU32(C);
464 AugmentationStringSize = alignTo(Value: AS.getU32(C), Align: 4);
465
466 if (!C)
467 return HeaderError(C.takeError());
468
469 if (!AS.isValidOffsetForDataOfSize(offset: C.tell(), length: AugmentationStringSize))
470 return HeaderError(createStringError(EC: errc::illegal_byte_sequence,
471 S: "cannot read header augmentation"));
472 AugmentationString.resize(N: AugmentationStringSize);
473 AS.getU8(C, Dst: reinterpret_cast<uint8_t *>(AugmentationString.data()),
474 Count: AugmentationStringSize);
475 *Offset = C.tell();
476 return C.takeError();
477}
478
479void DWARFDebugNames::Abbrev::dump(ScopedPrinter &W) const {
480 DictScope AbbrevScope(W, ("Abbreviation 0x" + Twine::utohexstr(Val: Code)).str());
481 W.startLine() << formatv(Fmt: "Tag: {0}\n", Vals: Tag);
482
483 for (const auto &Attr : Attributes)
484 W.startLine() << formatv(Fmt: "{0}: {1}\n", Vals: Attr.Index, Vals: Attr.Form);
485}
486
487static constexpr DWARFDebugNames::AttributeEncoding sentinelAttrEnc() {
488 return {dwarf::Index(0), dwarf::Form(0)};
489}
490
491static bool isSentinel(const DWARFDebugNames::AttributeEncoding &AE) {
492 return AE == sentinelAttrEnc();
493}
494
495static DWARFDebugNames::Abbrev sentinelAbbrev() {
496 return DWARFDebugNames::Abbrev(0, dwarf::Tag(0), 0, {});
497}
498
499static bool isSentinel(const DWARFDebugNames::Abbrev &Abbr) {
500 return Abbr.Code == 0;
501}
502
503DWARFDebugNames::Abbrev DWARFDebugNames::AbbrevMapInfo::getEmptyKey() {
504 return sentinelAbbrev();
505}
506
507DWARFDebugNames::Abbrev DWARFDebugNames::AbbrevMapInfo::getTombstoneKey() {
508 return DWARFDebugNames::Abbrev(~0, dwarf::Tag(0), 0, {});
509}
510
511Expected<DWARFDebugNames::AttributeEncoding>
512DWARFDebugNames::NameIndex::extractAttributeEncoding(uint64_t *Offset) {
513 if (*Offset >= Offsets.EntriesBase) {
514 return createStringError(EC: errc::illegal_byte_sequence,
515 S: "Incorrectly terminated abbreviation table.");
516 }
517
518 uint32_t Index = Section.AccelSection.getULEB128(offset_ptr: Offset);
519 uint32_t Form = Section.AccelSection.getULEB128(offset_ptr: Offset);
520 return AttributeEncoding(dwarf::Index(Index), dwarf::Form(Form));
521}
522
523Expected<std::vector<DWARFDebugNames::AttributeEncoding>>
524DWARFDebugNames::NameIndex::extractAttributeEncodings(uint64_t *Offset) {
525 std::vector<AttributeEncoding> Result;
526 for (;;) {
527 auto AttrEncOr = extractAttributeEncoding(Offset);
528 if (!AttrEncOr)
529 return AttrEncOr.takeError();
530 if (isSentinel(AE: *AttrEncOr))
531 return std::move(Result);
532
533 Result.emplace_back(args&: *AttrEncOr);
534 }
535}
536
537Expected<DWARFDebugNames::Abbrev>
538DWARFDebugNames::NameIndex::extractAbbrev(uint64_t *Offset) {
539 if (*Offset >= Offsets.EntriesBase) {
540 return createStringError(EC: errc::illegal_byte_sequence,
541 S: "Incorrectly terminated abbreviation table.");
542 }
543 const uint64_t AbbrevOffset = *Offset;
544 uint32_t Code = Section.AccelSection.getULEB128(offset_ptr: Offset);
545 if (Code == 0)
546 return sentinelAbbrev();
547
548 uint32_t Tag = Section.AccelSection.getULEB128(offset_ptr: Offset);
549 auto AttrEncOr = extractAttributeEncodings(Offset);
550 if (!AttrEncOr)
551 return AttrEncOr.takeError();
552 return Abbrev(Code, dwarf::Tag(Tag), AbbrevOffset, std::move(*AttrEncOr));
553}
554
555DWARFDebugNames::DWARFDebugNamesOffsets
556dwarf::findDebugNamesOffsets(uint64_t EndOfHeaderOffset,
557 const DWARFDebugNames::Header &Hdr) {
558 uint64_t DwarfSize = getDwarfOffsetByteSize(Format: Hdr.Format);
559 DWARFDebugNames::DWARFDebugNamesOffsets Ret;
560 Ret.CUsBase = EndOfHeaderOffset;
561 Ret.BucketsBase = Ret.CUsBase + Hdr.CompUnitCount * DwarfSize +
562 Hdr.LocalTypeUnitCount * DwarfSize +
563 Hdr.ForeignTypeUnitCount * 8;
564 Ret.HashesBase = Ret.BucketsBase + Hdr.BucketCount * 4;
565 Ret.StringOffsetsBase =
566 Ret.HashesBase + (Hdr.BucketCount > 0 ? Hdr.NameCount * 4 : 0);
567 Ret.EntryOffsetsBase = Ret.StringOffsetsBase + Hdr.NameCount * DwarfSize;
568 Ret.EntriesBase =
569 Ret.EntryOffsetsBase + Hdr.NameCount * DwarfSize + Hdr.AbbrevTableSize;
570 return Ret;
571}
572
573Error DWARFDebugNames::NameIndex::extract() {
574 const DWARFDataExtractor &AS = Section.AccelSection;
575 uint64_t EndOfHeaderOffset = Base;
576 if (Error E = Hdr.extract(AS, Offset: &EndOfHeaderOffset))
577 return E;
578
579 const unsigned SectionOffsetSize = dwarf::getDwarfOffsetByteSize(Format: Hdr.Format);
580 Offsets = dwarf::findDebugNamesOffsets(EndOfHeaderOffset, Hdr);
581
582 uint64_t Offset =
583 Offsets.EntryOffsetsBase + (Hdr.NameCount * SectionOffsetSize);
584
585 if (!AS.isValidOffsetForDataOfSize(offset: Offset, length: Hdr.AbbrevTableSize))
586 return createStringError(EC: errc::illegal_byte_sequence,
587 S: "Section too small: cannot read abbreviations.");
588
589 Offsets.EntriesBase = Offset + Hdr.AbbrevTableSize;
590
591 for (;;) {
592 auto AbbrevOr = extractAbbrev(Offset: &Offset);
593 if (!AbbrevOr)
594 return AbbrevOr.takeError();
595 if (isSentinel(Abbr: *AbbrevOr))
596 return Error::success();
597
598 if (!Abbrevs.insert(V: std::move(*AbbrevOr)).second)
599 return createStringError(EC: errc::invalid_argument,
600 S: "Duplicate abbreviation code.");
601 }
602}
603
604DWARFDebugNames::Entry::Entry(const NameIndex &NameIdx, const Abbrev &Abbr)
605 : NameIdx(&NameIdx), Abbr(&Abbr) {
606 // This merely creates form values. It is up to the caller
607 // (NameIndex::getEntry) to populate them.
608 Values.reserve(N: Abbr.Attributes.size());
609 for (const auto &Attr : Abbr.Attributes)
610 Values.emplace_back(Args: Attr.Form);
611}
612
613std::optional<DWARFFormValue>
614DWARFDebugNames::Entry::lookup(dwarf::Index Index) const {
615 assert(Abbr->Attributes.size() == Values.size());
616 for (auto Tuple : zip_first(t: Abbr->Attributes, u: Values)) {
617 if (std::get<0>(t&: Tuple).Index == Index)
618 return std::get<1>(t&: Tuple);
619 }
620 return std::nullopt;
621}
622
623bool DWARFDebugNames::Entry::hasParentInformation() const {
624 return lookup(Index: dwarf::DW_IDX_parent).has_value();
625}
626
627std::optional<uint64_t> DWARFDebugNames::Entry::getDIEUnitOffset() const {
628 if (std::optional<DWARFFormValue> Off = lookup(Index: dwarf::DW_IDX_die_offset))
629 return Off->getAsReferenceUVal();
630 return std::nullopt;
631}
632
633std::optional<uint64_t> DWARFDebugNames::Entry::getRelatedCUIndex() const {
634 // Return the DW_IDX_compile_unit attribute value if it is specified.
635 if (std::optional<DWARFFormValue> Off = lookup(Index: dwarf::DW_IDX_compile_unit))
636 return Off->getAsUnsignedConstant();
637 // In a per-CU index, the entries without a DW_IDX_compile_unit attribute
638 // implicitly refer to the single CU.
639 if (NameIdx->getCUCount() == 1)
640 return 0;
641 return std::nullopt;
642}
643
644std::optional<uint64_t> DWARFDebugNames::Entry::getCUIndex() const {
645 // Return the DW_IDX_compile_unit attribute value but only if we don't have a
646 // DW_IDX_type_unit attribute. Use Entry::getRelatedCUIndex() to get the
647 // associated CU index if this behaviour is not desired.
648 if (lookup(Index: dwarf::DW_IDX_type_unit).has_value())
649 return std::nullopt;
650 return getRelatedCUIndex();
651}
652
653std::optional<uint64_t> DWARFDebugNames::Entry::getCUOffset() const {
654 std::optional<uint64_t> Index = getCUIndex();
655 if (!Index || *Index >= NameIdx->getCUCount())
656 return std::nullopt;
657 return NameIdx->getCUOffset(CU: *Index);
658}
659
660std::optional<uint64_t> DWARFDebugNames::Entry::getRelatedCUOffset() const {
661 std::optional<uint64_t> Index = getRelatedCUIndex();
662 if (!Index || *Index >= NameIdx->getCUCount())
663 return std::nullopt;
664 return NameIdx->getCUOffset(CU: *Index);
665}
666
667std::optional<uint64_t> DWARFDebugNames::Entry::getLocalTUOffset() const {
668 std::optional<uint64_t> Index = getTUIndex();
669 if (!Index || *Index >= NameIdx->getLocalTUCount())
670 return std::nullopt;
671 return NameIdx->getLocalTUOffset(TU: *Index);
672}
673
674std::optional<uint64_t>
675DWARFDebugNames::Entry::getForeignTUTypeSignature() const {
676 std::optional<uint64_t> Index = getTUIndex();
677 const uint32_t NumLocalTUs = NameIdx->getLocalTUCount();
678 if (!Index || *Index < NumLocalTUs)
679 return std::nullopt; // Invalid TU index or TU index is for a local TU
680 // The foreign TU index is the TU index minus the number of local TUs.
681 const uint64_t ForeignTUIndex = *Index - NumLocalTUs;
682 if (ForeignTUIndex >= NameIdx->getForeignTUCount())
683 return std::nullopt; // Invalid foreign TU index.
684 return NameIdx->getForeignTUSignature(TU: ForeignTUIndex);
685}
686
687std::optional<uint64_t> DWARFDebugNames::Entry::getTUIndex() const {
688 if (std::optional<DWARFFormValue> Off = lookup(Index: dwarf::DW_IDX_type_unit))
689 return Off->getAsUnsignedConstant();
690 return std::nullopt;
691}
692
693Expected<std::optional<DWARFDebugNames::Entry>>
694DWARFDebugNames::Entry::getParentDIEEntry() const {
695 // The offset of the accelerator table entry for the parent.
696 std::optional<DWARFFormValue> ParentEntryOff = lookup(Index: dwarf::DW_IDX_parent);
697 assert(ParentEntryOff.has_value() && "hasParentInformation() must be called");
698
699 if (ParentEntryOff->getForm() == dwarf::Form::DW_FORM_flag_present)
700 return std::nullopt;
701 return NameIdx->getEntryAtRelativeOffset(Offset: ParentEntryOff->getRawUValue());
702}
703
704void DWARFDebugNames::Entry::dumpParentIdx(
705 ScopedPrinter &W, const DWARFFormValue &FormValue) const {
706 Expected<std::optional<Entry>> ParentEntry = getParentDIEEntry();
707 if (!ParentEntry) {
708 W.getOStream() << "<invalid offset data>";
709 consumeError(Err: ParentEntry.takeError());
710 return;
711 }
712
713 if (!ParentEntry->has_value()) {
714 W.getOStream() << "<parent not indexed>";
715 return;
716 }
717
718 auto AbsoluteOffset = NameIdx->Offsets.EntriesBase + FormValue.getRawUValue();
719 W.getOStream() << "Entry @ 0x" + Twine::utohexstr(Val: AbsoluteOffset);
720}
721
722void DWARFDebugNames::Entry::dump(ScopedPrinter &W) const {
723 W.startLine() << formatv(Fmt: "Abbrev: {0:x}\n", Vals: Abbr->Code);
724 W.startLine() << formatv(Fmt: "Tag: {0}\n", Vals: Abbr->Tag);
725 assert(Abbr->Attributes.size() == Values.size());
726 for (auto Tuple : zip_first(t: Abbr->Attributes, u: Values)) {
727 auto Index = std::get<0>(t&: Tuple).Index;
728 W.startLine() << formatv(Fmt: "{0}: ", Vals&: Index);
729
730 auto FormValue = std::get<1>(t&: Tuple);
731 if (Index == dwarf::Index::DW_IDX_parent)
732 dumpParentIdx(W, FormValue);
733 else
734 FormValue.dump(OS&: W.getOStream());
735 W.getOStream() << '\n';
736 }
737}
738
739char DWARFDebugNames::SentinelError::ID;
740std::error_code DWARFDebugNames::SentinelError::convertToErrorCode() const {
741 return inconvertibleErrorCode();
742}
743
744uint64_t DWARFDebugNames::NameIndex::getCUOffset(uint32_t CU) const {
745 assert(CU < Hdr.CompUnitCount);
746 const unsigned SectionOffsetSize = dwarf::getDwarfOffsetByteSize(Format: Hdr.Format);
747 uint64_t Offset = Offsets.CUsBase + SectionOffsetSize * CU;
748 return Section.AccelSection.getRelocatedValue(Size: SectionOffsetSize, Off: &Offset);
749}
750
751uint64_t DWARFDebugNames::NameIndex::getLocalTUOffset(uint32_t TU) const {
752 assert(TU < Hdr.LocalTypeUnitCount);
753 const unsigned SectionOffsetSize = dwarf::getDwarfOffsetByteSize(Format: Hdr.Format);
754 uint64_t Offset =
755 Offsets.CUsBase + SectionOffsetSize * (Hdr.CompUnitCount + TU);
756 return Section.AccelSection.getRelocatedValue(Size: SectionOffsetSize, Off: &Offset);
757}
758
759uint64_t DWARFDebugNames::NameIndex::getForeignTUSignature(uint32_t TU) const {
760 assert(TU < Hdr.ForeignTypeUnitCount);
761 const unsigned SectionOffsetSize = dwarf::getDwarfOffsetByteSize(Format: Hdr.Format);
762 uint64_t Offset =
763 Offsets.CUsBase +
764 SectionOffsetSize * (Hdr.CompUnitCount + Hdr.LocalTypeUnitCount) + 8 * TU;
765 return Section.AccelSection.getU64(offset_ptr: &Offset);
766}
767
768Expected<DWARFDebugNames::Entry>
769DWARFDebugNames::NameIndex::getEntry(uint64_t *Offset) const {
770 const DWARFDataExtractor &AS = Section.AccelSection;
771 if (!AS.isValidOffset(offset: *Offset))
772 return createStringError(EC: errc::illegal_byte_sequence,
773 S: "Incorrectly terminated entry list.");
774
775 uint32_t AbbrevCode = AS.getULEB128(offset_ptr: Offset);
776 if (AbbrevCode == 0)
777 return make_error<SentinelError>();
778
779 const auto AbbrevIt = Abbrevs.find_as(Val: AbbrevCode);
780 if (AbbrevIt == Abbrevs.end())
781 return createStringError(EC: errc::invalid_argument, S: "Invalid abbreviation.");
782
783 Entry E(*this, *AbbrevIt);
784
785 dwarf::FormParams FormParams = {.Version: Hdr.Version, .AddrSize: 0, .Format: Hdr.Format};
786 for (auto &Value : E.Values) {
787 if (!Value.extractValue(Data: AS, OffsetPtr: Offset, FormParams))
788 return createStringError(EC: errc::io_error,
789 S: "Error extracting index attribute values.");
790 }
791 return std::move(E);
792}
793
794DWARFDebugNames::NameTableEntry
795DWARFDebugNames::NameIndex::getNameTableEntry(uint32_t Index) const {
796 assert(0 < Index && Index <= Hdr.NameCount);
797 const unsigned SectionOffsetSize = dwarf::getDwarfOffsetByteSize(Format: Hdr.Format);
798 uint64_t StringOffsetOffset =
799 Offsets.StringOffsetsBase + SectionOffsetSize * (Index - 1);
800 uint64_t EntryOffsetOffset =
801 Offsets.EntryOffsetsBase + SectionOffsetSize * (Index - 1);
802 const DWARFDataExtractor &AS = Section.AccelSection;
803
804 uint64_t StringOffset =
805 AS.getRelocatedValue(Size: SectionOffsetSize, Off: &StringOffsetOffset);
806 uint64_t EntryOffset = AS.getUnsigned(offset_ptr: &EntryOffsetOffset, byte_size: SectionOffsetSize);
807 EntryOffset += Offsets.EntriesBase;
808 return {Section.StringSection, Index, StringOffset, EntryOffset};
809}
810
811uint32_t
812DWARFDebugNames::NameIndex::getBucketArrayEntry(uint32_t Bucket) const {
813 assert(Bucket < Hdr.BucketCount);
814 uint64_t BucketOffset = Offsets.BucketsBase + 4 * Bucket;
815 return Section.AccelSection.getU32(offset_ptr: &BucketOffset);
816}
817
818uint32_t DWARFDebugNames::NameIndex::getHashArrayEntry(uint32_t Index) const {
819 assert(0 < Index && Index <= Hdr.NameCount);
820 uint64_t HashOffset = Offsets.HashesBase + 4 * (Index - 1);
821 return Section.AccelSection.getU32(offset_ptr: &HashOffset);
822}
823
824// Returns true if we should continue scanning for entries, false if this is the
825// last (sentinel) entry). In case of a parsing error we also return false, as
826// it's not possible to recover this entry list (but the other lists may still
827// parse OK).
828bool DWARFDebugNames::NameIndex::dumpEntry(ScopedPrinter &W,
829 uint64_t *Offset) const {
830 uint64_t EntryId = *Offset;
831 auto EntryOr = getEntry(Offset);
832 if (!EntryOr) {
833 handleAllErrors(E: EntryOr.takeError(), Handlers: [](const SentinelError &) {},
834 Handlers: [&W](const ErrorInfoBase &EI) { EI.log(OS&: W.startLine()); });
835 return false;
836 }
837
838 DictScope EntryScope(W, ("Entry @ 0x" + Twine::utohexstr(Val: EntryId)).str());
839 EntryOr->dump(W);
840 return true;
841}
842
843void DWARFDebugNames::NameIndex::dumpName(ScopedPrinter &W,
844 const NameTableEntry &NTE,
845 std::optional<uint32_t> Hash) const {
846 DictScope NameScope(W, ("Name " + Twine(NTE.getIndex())).str());
847 if (Hash)
848 W.printHex(Label: "Hash", Value: *Hash);
849
850 W.startLine() << format(Fmt: "String: 0x%08" PRIx64, Vals: NTE.getStringOffset());
851 W.getOStream() << " \"" << NTE.getString() << "\"\n";
852
853 uint64_t EntryOffset = NTE.getEntryOffset();
854 while (dumpEntry(W, Offset: &EntryOffset))
855 /*empty*/;
856}
857
858void DWARFDebugNames::NameIndex::dumpCUs(ScopedPrinter &W) const {
859 ListScope CUScope(W, "Compilation Unit offsets");
860 for (uint32_t CU = 0; CU < Hdr.CompUnitCount; ++CU)
861 W.startLine() << format(Fmt: "CU[%u]: 0x%08" PRIx64 "\n", Vals: CU, Vals: getCUOffset(CU));
862}
863
864void DWARFDebugNames::NameIndex::dumpLocalTUs(ScopedPrinter &W) const {
865 if (Hdr.LocalTypeUnitCount == 0)
866 return;
867
868 ListScope TUScope(W, "Local Type Unit offsets");
869 for (uint32_t TU = 0; TU < Hdr.LocalTypeUnitCount; ++TU)
870 W.startLine() << format(Fmt: "LocalTU[%u]: 0x%08" PRIx64 "\n", Vals: TU,
871 Vals: getLocalTUOffset(TU));
872}
873
874void DWARFDebugNames::NameIndex::dumpForeignTUs(ScopedPrinter &W) const {
875 if (Hdr.ForeignTypeUnitCount == 0)
876 return;
877
878 ListScope TUScope(W, "Foreign Type Unit signatures");
879 for (uint32_t TU = 0; TU < Hdr.ForeignTypeUnitCount; ++TU) {
880 W.startLine() << format(Fmt: "ForeignTU[%u]: 0x%016" PRIx64 "\n", Vals: TU,
881 Vals: getForeignTUSignature(TU));
882 }
883}
884
885void DWARFDebugNames::NameIndex::dumpAbbreviations(ScopedPrinter &W) const {
886 ListScope AbbrevsScope(W, "Abbreviations");
887 std::vector<const Abbrev *> AbbrevsVect;
888 for (const DWARFDebugNames::Abbrev &Abbr : Abbrevs)
889 AbbrevsVect.push_back(x: &Abbr);
890 llvm::sort(C&: AbbrevsVect, Comp: [](const Abbrev *LHS, const Abbrev *RHS) {
891 return LHS->AbbrevOffset < RHS->AbbrevOffset;
892 });
893 for (const DWARFDebugNames::Abbrev *Abbr : AbbrevsVect)
894 Abbr->dump(W);
895}
896
897void DWARFDebugNames::NameIndex::dumpBucket(ScopedPrinter &W,
898 uint32_t Bucket) const {
899 ListScope BucketScope(W, ("Bucket " + Twine(Bucket)).str());
900 uint32_t Index = getBucketArrayEntry(Bucket);
901 if (Index == 0) {
902 W.printString(Value: "EMPTY");
903 return;
904 }
905 if (Index > Hdr.NameCount) {
906 W.printString(Value: "Name index is invalid");
907 return;
908 }
909
910 for (; Index <= Hdr.NameCount; ++Index) {
911 uint32_t Hash = getHashArrayEntry(Index);
912 if (Hash % Hdr.BucketCount != Bucket)
913 break;
914
915 dumpName(W, NTE: getNameTableEntry(Index), Hash);
916 }
917}
918
919LLVM_DUMP_METHOD void DWARFDebugNames::NameIndex::dump(ScopedPrinter &W) const {
920 DictScope UnitScope(W, ("Name Index @ 0x" + Twine::utohexstr(Val: Base)).str());
921 Hdr.dump(W);
922 dumpCUs(W);
923 dumpLocalTUs(W);
924 dumpForeignTUs(W);
925 dumpAbbreviations(W);
926
927 if (Hdr.BucketCount > 0) {
928 for (uint32_t Bucket = 0; Bucket < Hdr.BucketCount; ++Bucket)
929 dumpBucket(W, Bucket);
930 return;
931 }
932
933 W.startLine() << "Hash table not present\n";
934 for (const NameTableEntry &NTE : *this)
935 dumpName(W, NTE, Hash: std::nullopt);
936}
937
938Error DWARFDebugNames::extract() {
939 uint64_t Offset = 0;
940 while (AccelSection.isValidOffset(offset: Offset)) {
941 NameIndex Next(*this, Offset);
942 if (Error E = Next.extract())
943 return E;
944 Offset = Next.getNextUnitOffset();
945 NameIndices.push_back(Elt: std::move(Next));
946 }
947 return Error::success();
948}
949
950iterator_range<DWARFDebugNames::ValueIterator>
951DWARFDebugNames::NameIndex::equal_range(StringRef Key) const {
952 return make_range(x: ValueIterator(*this, Key), y: ValueIterator());
953}
954
955LLVM_DUMP_METHOD void DWARFDebugNames::dump(raw_ostream &OS) const {
956 ScopedPrinter W(OS);
957 for (const NameIndex &NI : NameIndices)
958 NI.dump(W);
959}
960
961std::optional<uint64_t>
962DWARFDebugNames::ValueIterator::findEntryOffsetInCurrentIndex() {
963 const Header &Hdr = CurrentIndex->Hdr;
964 if (Hdr.BucketCount == 0) {
965 // No Hash Table, We need to search through all names in the Name Index.
966 for (const NameTableEntry &NTE : *CurrentIndex) {
967 if (NTE.sameNameAs(Target: Key))
968 return NTE.getEntryOffset();
969 }
970 return std::nullopt;
971 }
972
973 // The Name Index has a Hash Table, so use that to speed up the search.
974 // Compute the Key Hash, if it has not been done already.
975 if (!Hash)
976 Hash = caseFoldingDjbHash(Buffer: Key);
977 uint32_t Bucket = *Hash % Hdr.BucketCount;
978 uint32_t Index = CurrentIndex->getBucketArrayEntry(Bucket);
979 if (Index == 0)
980 return std::nullopt; // Empty bucket
981
982 for (; Index <= Hdr.NameCount; ++Index) {
983 uint32_t HashAtIndex = CurrentIndex->getHashArrayEntry(Index);
984 if (HashAtIndex % Hdr.BucketCount != Bucket)
985 return std::nullopt; // End of bucket
986 // Only compare names if the hashes match.
987 if (HashAtIndex != Hash)
988 continue;
989
990 NameTableEntry NTE = CurrentIndex->getNameTableEntry(Index);
991 if (NTE.sameNameAs(Target: Key))
992 return NTE.getEntryOffset();
993 }
994 return std::nullopt;
995}
996
997bool DWARFDebugNames::ValueIterator::getEntryAtCurrentOffset() {
998 auto EntryOr = CurrentIndex->getEntry(Offset: &DataOffset);
999 if (!EntryOr) {
1000 consumeError(Err: EntryOr.takeError());
1001 return false;
1002 }
1003 CurrentEntry = std::move(*EntryOr);
1004 return true;
1005}
1006
1007bool DWARFDebugNames::ValueIterator::findInCurrentIndex() {
1008 std::optional<uint64_t> Offset = findEntryOffsetInCurrentIndex();
1009 if (!Offset)
1010 return false;
1011 DataOffset = *Offset;
1012 return getEntryAtCurrentOffset();
1013}
1014
1015void DWARFDebugNames::ValueIterator::searchFromStartOfCurrentIndex() {
1016 for (const NameIndex *End = CurrentIndex->Section.NameIndices.end();
1017 CurrentIndex != End; ++CurrentIndex) {
1018 if (findInCurrentIndex())
1019 return;
1020 }
1021 setEnd();
1022}
1023
1024void DWARFDebugNames::ValueIterator::next() {
1025 assert(CurrentIndex && "Incrementing an end() iterator?");
1026
1027 // First try the next entry in the current Index.
1028 if (getEntryAtCurrentOffset())
1029 return;
1030
1031 // If we're a local iterator or we have reached the last Index, we're done.
1032 if (IsLocal || CurrentIndex == &CurrentIndex->Section.NameIndices.back()) {
1033 setEnd();
1034 return;
1035 }
1036
1037 // Otherwise, try the next index.
1038 ++CurrentIndex;
1039 searchFromStartOfCurrentIndex();
1040}
1041
1042DWARFDebugNames::ValueIterator::ValueIterator(const DWARFDebugNames &AccelTable,
1043 StringRef Key)
1044 : CurrentIndex(AccelTable.NameIndices.begin()), IsLocal(false),
1045 Key(std::string(Key)) {
1046 searchFromStartOfCurrentIndex();
1047}
1048
1049DWARFDebugNames::ValueIterator::ValueIterator(
1050 const DWARFDebugNames::NameIndex &NI, StringRef Key)
1051 : CurrentIndex(&NI), IsLocal(true), Key(std::string(Key)) {
1052 if (!findInCurrentIndex())
1053 setEnd();
1054}
1055
1056iterator_range<DWARFDebugNames::ValueIterator>
1057DWARFDebugNames::equal_range(StringRef Key) const {
1058 if (NameIndices.empty())
1059 return make_range(x: ValueIterator(), y: ValueIterator());
1060 return make_range(x: ValueIterator(*this, Key), y: ValueIterator());
1061}
1062
1063const DWARFDebugNames::NameIndex *
1064DWARFDebugNames::getCUOrTUNameIndex(uint64_t UnitOffset) {
1065 if (UnitOffsetToNameIndex.size() == 0 && NameIndices.size() > 0) {
1066 for (const auto &NI : *this) {
1067 for (uint32_t CU = 0; CU < NI.getCUCount(); ++CU)
1068 UnitOffsetToNameIndex.try_emplace(Key: NI.getCUOffset(CU), Args: &NI);
1069 for (uint32_t TU = 0; TU < NI.getLocalTUCount(); ++TU)
1070 UnitOffsetToNameIndex.try_emplace(Key: NI.getLocalTUOffset(TU), Args: &NI);
1071 }
1072 }
1073 return UnitOffsetToNameIndex.lookup(Val: UnitOffset);
1074}
1075
1076static bool isObjCSelector(StringRef Name) {
1077 return Name.size() > 2 && (Name[0] == '-' || Name[0] == '+') &&
1078 (Name[1] == '[');
1079}
1080
1081std::optional<ObjCSelectorNames> llvm::getObjCNamesIfSelector(StringRef Name) {
1082 if (!isObjCSelector(Name))
1083 return std::nullopt;
1084 // "-[Atom setMass:]"
1085 StringRef ClassNameStart(Name.drop_front(N: 2));
1086 size_t FirstSpace = ClassNameStart.find(C: ' ');
1087 if (FirstSpace == StringRef::npos)
1088 return std::nullopt;
1089
1090 StringRef SelectorStart = ClassNameStart.drop_front(N: FirstSpace + 1);
1091 if (!SelectorStart.size())
1092 return std::nullopt;
1093
1094 ObjCSelectorNames Ans;
1095 Ans.ClassName = ClassNameStart.take_front(N: FirstSpace);
1096 Ans.Selector = SelectorStart.drop_back(); // drop ']';
1097
1098 // "-[Class(Category) selector :withArg ...]"
1099 if (Ans.ClassName.back() == ')') {
1100 size_t OpenParens = Ans.ClassName.find(C: '(');
1101 if (OpenParens != StringRef::npos) {
1102 Ans.ClassNameNoCategory = Ans.ClassName.take_front(N: OpenParens);
1103
1104 Ans.MethodNameNoCategory = Name.take_front(N: OpenParens + 2);
1105 // FIXME: The missing space here may be a bug, but dsymutil-classic also
1106 // does it this way.
1107 append_range(C&: *Ans.MethodNameNoCategory, R&: SelectorStart);
1108 }
1109 }
1110 return Ans;
1111}
1112
1113std::optional<StringRef> llvm::StripTemplateParameters(StringRef Name) {
1114 // We are looking for template parameters to strip from Name. e.g.
1115 //
1116 // operator<<B>
1117 //
1118 // We look for > at the end but if it does not contain any < then we
1119 // have something like operator>>. We check for the operator<=> case.
1120 if (!Name.ends_with(Suffix: ">") || Name.count(Str: "<") == 0 || Name.ends_with(Suffix: "<=>"))
1121 return {};
1122
1123 // How many < until we have the start of the template parameters.
1124 size_t NumLeftAnglesToSkip = 1;
1125
1126 // If we have operator<=> then we need to skip its < as well.
1127 NumLeftAnglesToSkip += Name.count(Str: "<=>");
1128
1129 size_t RightAngleCount = Name.count(C: '>');
1130 size_t LeftAngleCount = Name.count(C: '<');
1131
1132 // If we have more < than > we have operator< or operator<<
1133 // we to account for their < as well.
1134 if (LeftAngleCount > RightAngleCount)
1135 NumLeftAnglesToSkip += LeftAngleCount - RightAngleCount;
1136
1137 size_t StartOfTemplate = 0;
1138 while (NumLeftAnglesToSkip--)
1139 StartOfTemplate = Name.find(C: '<', From: StartOfTemplate) + 1;
1140
1141 return Name.substr(Start: 0, N: StartOfTemplate - 1);
1142}
1143