1//===- tools/dsymutil/DwarfLinkerForBinary.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 "DwarfLinkerForBinary.h"
10#include "BinaryHolder.h"
11#include "DebugMap.h"
12#include "MachOUtils.h"
13#include "SwiftModule.h"
14#include "dsymutil.h"
15#include "llvm/ADT/ArrayRef.h"
16#include "llvm/ADT/DenseMap.h"
17#include "llvm/ADT/FoldingSet.h"
18#include "llvm/ADT/Hashing.h"
19#include "llvm/ADT/STLExtras.h"
20#include "llvm/ADT/SmallString.h"
21#include "llvm/ADT/StringRef.h"
22#include "llvm/ADT/StringSet.h"
23#include "llvm/ADT/Twine.h"
24#include "llvm/BinaryFormat/Dwarf.h"
25#include "llvm/BinaryFormat/MachO.h"
26#include "llvm/BinaryFormat/Swift.h"
27#include "llvm/CodeGen/AccelTable.h"
28#include "llvm/CodeGen/AsmPrinter.h"
29#include "llvm/CodeGen/DIE.h"
30#include "llvm/CodeGen/NonRelocatableStringpool.h"
31#include "llvm/Config/config.h"
32#include "llvm/DWARFLinker/Classic/DWARFLinker.h"
33#include "llvm/DWARFLinker/Classic/DWARFStreamer.h"
34#include "llvm/DWARFLinker/Parallel/DWARFLinker.h"
35#include "llvm/DebugInfo/DIContext.h"
36#include "llvm/DebugInfo/DWARF/DWARFAbbreviationDeclaration.h"
37#include "llvm/DebugInfo/DWARF/DWARFContext.h"
38#include "llvm/DebugInfo/DWARF/DWARFDataExtractor.h"
39#include "llvm/DebugInfo/DWARF/DWARFDebugLine.h"
40#include "llvm/DebugInfo/DWARF/DWARFDebugRangeList.h"
41#include "llvm/DebugInfo/DWARF/DWARFDie.h"
42#include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
43#include "llvm/DebugInfo/DWARF/DWARFSection.h"
44#include "llvm/DebugInfo/DWARF/DWARFUnit.h"
45#include "llvm/DebugInfo/DWARF/LowLevel/DWARFExpression.h"
46#include "llvm/MC/MCAsmBackend.h"
47#include "llvm/MC/MCAsmInfo.h"
48#include "llvm/MC/MCCodeEmitter.h"
49#include "llvm/MC/MCContext.h"
50#include "llvm/MC/MCDwarf.h"
51#include "llvm/MC/MCInstrInfo.h"
52#include "llvm/MC/MCObjectFileInfo.h"
53#include "llvm/MC/MCObjectWriter.h"
54#include "llvm/MC/MCRegisterInfo.h"
55#include "llvm/MC/MCSection.h"
56#include "llvm/MC/MCStreamer.h"
57#include "llvm/MC/MCSubtargetInfo.h"
58#include "llvm/MC/MCTargetOptions.h"
59#include "llvm/MC/MCTargetOptionsCommandFlags.h"
60#include "llvm/MC/TargetRegistry.h"
61#include "llvm/Object/MachO.h"
62#include "llvm/Object/ObjectFile.h"
63#include "llvm/Object/SymbolicFile.h"
64#include "llvm/Support/Allocator.h"
65#include "llvm/Support/Casting.h"
66#include "llvm/Support/Compiler.h"
67#include "llvm/Support/DJB.h"
68#include "llvm/Support/DataExtractor.h"
69#include "llvm/Support/Error.h"
70#include "llvm/Support/ErrorHandling.h"
71#include "llvm/Support/ErrorOr.h"
72#include "llvm/Support/FileSystem.h"
73#include "llvm/Support/Format.h"
74#include "llvm/Support/LEB128.h"
75#include "llvm/Support/MathExtras.h"
76#include "llvm/Support/MemoryBuffer.h"
77#include "llvm/Support/Path.h"
78#include "llvm/Support/ThreadPool.h"
79#include "llvm/Support/ToolOutputFile.h"
80#include "llvm/Support/WithColor.h"
81#include "llvm/Support/raw_ostream.h"
82#include "llvm/Target/TargetMachine.h"
83#include "llvm/Target/TargetOptions.h"
84#include "llvm/TargetParser/Triple.h"
85#include <algorithm>
86#include <cassert>
87#include <cinttypes>
88#include <climits>
89#include <cstdint>
90#include <cstdlib>
91#include <cstring>
92#include <limits>
93#include <memory>
94#include <optional>
95#include <string>
96#include <system_error>
97#include <tuple>
98#include <utility>
99#include <vector>
100
101namespace llvm {
102
103static mc::RegisterMCTargetOptionsFlags MOF;
104
105using namespace dwarf_linker;
106
107namespace dsymutil {
108
109static void dumpDIE(const DWARFDie *DIE, bool Verbose) {
110 if (!DIE || !Verbose)
111 return;
112
113 DIDumpOptions DumpOpts;
114 DumpOpts.ChildRecurseDepth = 0;
115 DumpOpts.Verbose = Verbose;
116
117 WithColor::note() << " in DIE:\n";
118 DIE->dump(OS&: errs(), indent: 6 /* Indent */, DumpOpts);
119}
120
121/// Report a warning to the user, optionally including information about a
122/// specific \p DIE related to the warning.
123void DwarfLinkerForBinary::reportWarning(Twine Warning, Twine Context,
124 const DWARFDie *DIE) const {
125 // FIXME: implement warning logging which does not block other threads.
126 if (ErrorHandlerMutex.try_lock()) {
127 warn(Warning, Context);
128 dumpDIE(DIE, Verbose: Options.Verbose);
129 ErrorHandlerMutex.unlock();
130 }
131}
132
133void DwarfLinkerForBinary::reportError(Twine Error, Twine Context,
134 const DWARFDie *DIE) const {
135 // FIXME: implement error logging which does not block other threads.
136 if (ErrorHandlerMutex.try_lock()) {
137 error(Error, Context);
138 dumpDIE(DIE, Verbose: Options.Verbose);
139 ErrorHandlerMutex.unlock();
140 }
141}
142
143ErrorOr<const object::ObjectFile &>
144DwarfLinkerForBinary::loadObject(const DebugMapObject &Obj,
145 const Triple &Triple) {
146 auto ObjectEntry =
147 BinHolder.getObjectEntry(Filename: Obj.getObjectFilename(), Timestamp: Obj.getTimestamp());
148 if (!ObjectEntry) {
149 auto Err = ObjectEntry.takeError();
150 reportWarning(Warning: Twine(Obj.getObjectFilename()) + ": " +
151 toStringWithoutConsuming(E: Err),
152 Context: Obj.getObjectFilename());
153 return errorToErrorCode(Err: std::move(Err));
154 }
155
156 auto Object = ObjectEntry->getObject(T: Triple);
157 if (!Object) {
158 auto Err = Object.takeError();
159 reportWarning(Warning: Twine(Obj.getObjectFilename()) + ": " +
160 toStringWithoutConsuming(E: Err),
161 Context: Obj.getObjectFilename());
162 return errorToErrorCode(Err: std::move(Err));
163 }
164
165 return *Object;
166}
167
168static Error remarksErrorHandler(const DebugMapObject &DMO,
169 DwarfLinkerForBinary &Linker,
170 std::unique_ptr<FileError> FE) {
171 bool IsArchive = DMO.getObjectFilename().ends_with(Suffix: ")");
172 // Don't report errors for missing remark files from static
173 // archives.
174 if (!IsArchive)
175 return Error(std::move(FE));
176
177 std::string Message = FE->message();
178 Error E = FE->takeError();
179 Error NewE = handleErrors(E: std::move(E), Hs: [&](std::unique_ptr<ECError> EC) {
180 if (EC->convertToErrorCode() != std::errc::no_such_file_or_directory)
181 return Error(std::move(EC));
182
183 Linker.reportWarning(Warning: Message, Context: DMO.getObjectFilename());
184 return Error(Error::success());
185 });
186
187 if (!NewE)
188 return Error::success();
189
190 return createFileError(F: FE->getFileName(), E: std::move(NewE));
191}
192Error DwarfLinkerForBinary::emitRelocations(
193 const DebugMap &DM, std::vector<ObjectWithRelocMap> &ObjectsForLinking) {
194 // Return early if the "Resources" directory is not being written to.
195 if (!Options.ResourceDir)
196 return Error::success();
197
198 RelocationMap RM(DM.getTriple(), DM.getBinaryPath());
199 for (auto &Obj : ObjectsForLinking) {
200 if (!Obj.OutRelocs->isInitialized())
201 continue;
202 Obj.OutRelocs->addValidRelocs(RM);
203 }
204
205 SmallString<128> Path;
206 // Create the "Relocations" directory in the "Resources" directory, and
207 // create an architecture-specific directory in the "Relocations" directory.
208 StringRef ArchName = Triple::getArchName(Kind: RM.getTriple().getArch(),
209 SubArch: RM.getTriple().getSubArch());
210 sys::path::append(path&: Path, a: *Options.ResourceDir, b: "Relocations", c: ArchName);
211 if (std::error_code EC = sys::fs::create_directories(path: Path.str(), IgnoreExisting: true,
212 Perms: sys::fs::perms::all_all))
213 return errorCodeToError(EC);
214
215 // Append the file name.
216 sys::path::append(path&: Path, a: sys::path::filename(path: DM.getBinaryPath()));
217 Path.append(RHS: ".yml");
218
219 std::error_code EC;
220 raw_fd_ostream OS(Path.str(), EC, sys::fs::OF_Text);
221 if (EC)
222 return errorCodeToError(EC);
223
224 RM.print(OS);
225 return Error::success();
226}
227
228static Error emitRemarks(const LinkOptions &Options, StringRef BinaryPath,
229 StringRef ArchName, const remarks::RemarkLinker &RL) {
230 // Make sure we don't create the directories and the file if there is nothing
231 // to serialize.
232 if (RL.empty())
233 return Error::success();
234
235 SmallString<128> Path;
236 // Create the "Remarks" directory in the "Resources" directory.
237 sys::path::append(path&: Path, a: *Options.ResourceDir, b: "Remarks");
238 if (std::error_code EC = sys::fs::create_directories(path: Path.str(), IgnoreExisting: true,
239 Perms: sys::fs::perms::all_all))
240 return errorCodeToError(EC);
241
242 // Append the file name.
243 // For fat binaries, also append a dash and the architecture name.
244 sys::path::append(path&: Path, a: sys::path::filename(path: BinaryPath));
245 if (Options.NumDebugMaps > 1) {
246 // More than one debug map means we have a fat binary.
247 Path += '-';
248 Path += ArchName;
249 }
250
251 std::error_code EC;
252 raw_fd_ostream OS(Options.NoOutput ? "-" : Path.str(), EC,
253 Options.RemarksFormat == remarks::Format::Bitstream
254 ? sys::fs::OF_None
255 : sys::fs::OF_Text);
256 if (EC)
257 return errorCodeToError(EC);
258
259 if (Error E = RL.serialize(OS, RemarksFormat: Options.RemarksFormat))
260 return E;
261
262 return Error::success();
263}
264
265ErrorOr<std::unique_ptr<DWARFFile>> DwarfLinkerForBinary::loadObject(
266 const DebugMapObject &Obj, const DebugMap &DebugMap,
267 remarks::RemarkLinker &RL,
268 std::shared_ptr<DwarfLinkerForBinaryRelocationMap> DLBRM) {
269 auto ErrorOrObj = loadObject(Obj, Triple: DebugMap.getTriple());
270 std::unique_ptr<DWARFFile> Res;
271
272 if (ErrorOrObj) {
273 auto Context = DWARFContext::create(
274 Obj: *ErrorOrObj, RelocAction: DWARFContext::ProcessDebugRelocations::Process, L: nullptr,
275 DWPName: "",
276 RecoverableErrorHandler: [&](Error Err) {
277 handleAllErrors(E: std::move(Err), Handlers: [&](ErrorInfoBase &Info) {
278 reportError(Error: Info.message());
279 });
280 },
281 WarningHandler: [&](Error Warning) {
282 handleAllErrors(E: std::move(Warning), Handlers: [&](ErrorInfoBase &Info) {
283 reportWarning(Warning: Info.message());
284 });
285 });
286 DLBRM->init(Context&: *Context);
287 Res = std::make_unique<DWARFFile>(
288 args: Obj.getObjectFilename(), args: std::move(Context),
289 args: std::make_unique<AddressManager>(args&: *this, args: *ErrorOrObj, args: Obj, args&: DLBRM),
290 args: [&](StringRef FileName) { BinHolder.eraseObjectEntry(Filename: FileName); });
291
292 Error E = RL.link(Obj: *ErrorOrObj);
293 // FIXME: Remark parsing errors are not propagated to the user.
294 if (Error NewE = handleErrors(
295 E: std::move(E), Hs: [&](std::unique_ptr<FileError> EC) -> Error {
296 return remarksErrorHandler(DMO: Obj, Linker&: *this, FE: std::move(EC));
297 }))
298 return errorToErrorCode(Err: std::move(NewE));
299
300 return std::move(Res);
301 }
302
303 return ErrorOrObj.getError();
304}
305
306static bool binaryHasStrippableSwiftReflectionSections(
307 const DebugMap &Map, const LinkOptions &Options, BinaryHolder &BinHolder) {
308 // If the input binary has strippable swift5 reflection sections, there is no
309 // need to copy them to the .dSYM. Only copy them for binaries where the
310 // linker omitted the reflection metadata.
311 if (!Map.getBinaryPath().empty() &&
312 Options.FileType == DWARFLinkerBase::OutputFileType::Object) {
313
314 auto ObjectEntry = BinHolder.getObjectEntry(Filename: Map.getBinaryPath());
315 // If ObjectEntry or Object has an error, no binary exists, therefore no
316 // reflection sections exist.
317 if (!ObjectEntry) {
318 // Any errors will be diagnosed later in the main loop, ignore them here.
319 llvm::consumeError(Err: ObjectEntry.takeError());
320 return false;
321 }
322
323 auto Object =
324 ObjectEntry->getObjectAs<object::MachOObjectFile>(T: Map.getTriple());
325 if (!Object) {
326 // Any errors will be diagnosed later in the main loop, ignore them here.
327 llvm::consumeError(Err: Object.takeError());
328 return false;
329 }
330
331 for (auto &Section : Object->sections()) {
332 llvm::Expected<llvm::StringRef> NameOrErr =
333 Object->getSectionName(Sec: Section.getRawDataRefImpl());
334 if (!NameOrErr) {
335 llvm::consumeError(Err: NameOrErr.takeError());
336 continue;
337 }
338 NameOrErr->consume_back(Suffix: "__TEXT");
339 auto ReflectionSectionKind =
340 Object->mapReflectionSectionNameToEnumValue(SectionName: *NameOrErr);
341 if (Object->isReflectionSectionStrippable(ReflectionSectionKind)) {
342 return true;
343 }
344 }
345 }
346 return false;
347}
348
349/// Calculate the start of the strippable swift reflection sections in Dwarf.
350/// Note that there's an assumption that the reflection sections will appear
351/// in alphabetic order.
352static std::vector<uint64_t>
353calculateStartOfStrippableReflectionSections(const DebugMap &Map) {
354 using llvm::binaryformat::Swift5ReflectionSectionKind;
355 uint64_t AssocTySize = 0;
356 uint64_t FieldMdSize = 0;
357 for (const auto &Obj : Map.objects()) {
358 auto OF =
359 llvm::object::ObjectFile::createObjectFile(ObjectPath: Obj->getObjectFilename());
360 if (!OF) {
361 llvm::consumeError(Err: OF.takeError());
362 continue;
363 }
364 if (auto *MO = dyn_cast<llvm::object::MachOObjectFile>(Val: OF->getBinary())) {
365 for (auto &Section : MO->sections()) {
366 llvm::Expected<llvm::StringRef> NameOrErr =
367 MO->getSectionName(Sec: Section.getRawDataRefImpl());
368 if (!NameOrErr) {
369 llvm::consumeError(Err: NameOrErr.takeError());
370 continue;
371 }
372 NameOrErr->consume_back(Suffix: "__TEXT");
373 auto ReflSectionKind =
374 MO->mapReflectionSectionNameToEnumValue(SectionName: *NameOrErr);
375 switch (ReflSectionKind) {
376 case Swift5ReflectionSectionKind::assocty:
377 AssocTySize += Section.getSize();
378 break;
379 case Swift5ReflectionSectionKind::fieldmd:
380 FieldMdSize += Section.getSize();
381 break;
382 default:
383 break;
384 }
385 }
386 }
387 }
388 // Initialize the vector with enough space to fit every reflection section
389 // kind.
390 std::vector<uint64_t> SectionToOffset(Swift5ReflectionSectionKind::last, 0);
391 SectionToOffset[Swift5ReflectionSectionKind::assocty] = 0;
392 SectionToOffset[Swift5ReflectionSectionKind::fieldmd] =
393 llvm::alignTo(Value: AssocTySize, Align: 4);
394 SectionToOffset[Swift5ReflectionSectionKind::reflstr] = llvm::alignTo(
395 Value: SectionToOffset[Swift5ReflectionSectionKind::fieldmd] + FieldMdSize, Align: 4);
396
397 return SectionToOffset;
398}
399
400void DwarfLinkerForBinary::collectRelocationsToApplyToSwiftReflectionSections(
401 const object::SectionRef &Section, StringRef &Contents,
402 const llvm::object::MachOObjectFile *MO,
403 const std::vector<uint64_t> &SectionToOffsetInDwarf,
404 const llvm::dsymutil::DebugMapObject *Obj,
405 std::vector<MachOUtils::DwarfRelocationApplicationInfo> &RelocationsToApply)
406 const {
407 for (auto It = Section.relocation_begin(); It != Section.relocation_end();
408 ++It) {
409 object::DataRefImpl RelocDataRef = It->getRawDataRefImpl();
410 MachO::any_relocation_info MachOReloc = MO->getRelocation(Rel: RelocDataRef);
411
412 if (!object::MachOObjectFile::isMachOPairedReloc(
413 RelocType: MO->getAnyRelocationType(RE: MachOReloc), Arch: MO->getArch())) {
414 reportWarning(
415 Warning: "Unimplemented relocation type in strippable reflection section ",
416 Context: Obj->getObjectFilename());
417 continue;
418 }
419
420 auto CalculateAddressOfSymbolInDwarfSegment =
421 [&]() -> std::optional<int64_t> {
422 auto Symbol = It->getSymbol();
423 auto SymbolAbsoluteAddress = Symbol->getAddress();
424 if (!SymbolAbsoluteAddress)
425 return {};
426 auto Section = Symbol->getSection();
427 if (!Section) {
428 llvm::consumeError(Err: Section.takeError());
429 return {};
430 }
431
432 if ((*Section)->getObject()->section_end() == *Section)
433 return {};
434
435 auto SectionStart = (*Section)->getAddress();
436 auto SymbolAddressInSection = *SymbolAbsoluteAddress - SectionStart;
437 auto SectionName = (*Section)->getName();
438 if (!SectionName)
439 return {};
440 auto ReflSectionKind =
441 MO->mapReflectionSectionNameToEnumValue(SectionName: *SectionName);
442
443 int64_t SectionStartInLinkedBinary =
444 SectionToOffsetInDwarf[ReflSectionKind];
445
446 auto Addr = SectionStartInLinkedBinary + SymbolAddressInSection;
447 return Addr;
448 };
449
450 // The first symbol should always be in the section we're currently
451 // iterating over.
452 auto FirstSymbolAddress = CalculateAddressOfSymbolInDwarfSegment();
453 ++It;
454
455 bool ShouldSubtractDwarfVM = false;
456 // For the second symbol there are two possibilities.
457 std::optional<int64_t> SecondSymbolAddress;
458 auto Sym = It->getSymbol();
459 if (Sym != MO->symbol_end()) {
460 Expected<StringRef> SymbolName = Sym->getName();
461 if (SymbolName) {
462 if (const auto *Mapping = Obj->lookupSymbol(SymbolName: *SymbolName)) {
463 // First possibility: the symbol exists in the binary, and exists in a
464 // non-strippable section (for example, typeref, or __TEXT,__const),
465 // in which case we look up its address in the binary, which dsymutil
466 // will copy verbatim.
467 SecondSymbolAddress = Mapping->getValue().BinaryAddress;
468 // Since the symbols live in different segments, we have to substract
469 // the start of the Dwarf's vmaddr so the value calculated points to
470 // the correct place.
471 ShouldSubtractDwarfVM = true;
472 }
473 }
474 }
475
476 if (!SecondSymbolAddress) {
477 // Second possibility, this symbol is not present in the main binary, and
478 // must be in one of the strippable sections (for example, reflstr).
479 // Calculate its address in the same way as we did the first one.
480 SecondSymbolAddress = CalculateAddressOfSymbolInDwarfSegment();
481 }
482
483 if (!FirstSymbolAddress || !SecondSymbolAddress)
484 continue;
485
486 auto SectionName = Section.getName();
487 if (!SectionName)
488 continue;
489
490 int32_t Addend;
491 memcpy(dest: &Addend, src: Contents.data() + It->getOffset(), n: sizeof(int32_t));
492 int32_t Value = (*SecondSymbolAddress + Addend) - *FirstSymbolAddress;
493 auto ReflSectionKind =
494 MO->mapReflectionSectionNameToEnumValue(SectionName: *SectionName);
495 uint64_t AddressFromDwarfVM =
496 SectionToOffsetInDwarf[ReflSectionKind] + It->getOffset();
497 RelocationsToApply.emplace_back(args&: AddressFromDwarfVM, args&: Value,
498 args&: ShouldSubtractDwarfVM);
499 }
500}
501
502Error DwarfLinkerForBinary::copySwiftInterfaces(StringRef Architecture) const {
503 std::error_code EC;
504 SmallString<128> InputPath;
505 SmallString<128> Path;
506 sys::path::append(path&: Path, a: *Options.ResourceDir, b: "Swift", c: Architecture);
507 if ((EC = sys::fs::create_directories(path: Path.str(), IgnoreExisting: true,
508 Perms: sys::fs::perms::all_all)))
509 return make_error<StringError>(
510 Args: "cannot create directory: " + toString(E: errorCodeToError(EC)), Args&: EC);
511 unsigned BaseLength = Path.size();
512
513 for (auto &I : ParseableSwiftInterfaces) {
514 StringRef ModuleName = I.first;
515 StringRef InterfaceFile = I.second;
516 if (!Options.PrependPath.empty()) {
517 InputPath.clear();
518 sys::path::append(path&: InputPath, a: Options.PrependPath, b: InterfaceFile);
519 InterfaceFile = InputPath;
520 }
521 sys::path::append(path&: Path, a: ModuleName);
522 Path.append(RHS: ".swiftinterface");
523 if (Options.Verbose)
524 outs() << "copy parseable Swift interface " << InterfaceFile << " -> "
525 << Path.str() << '\n';
526
527 // copy_file attempts an APFS clone first, so this should be cheap.
528 if ((EC = sys::fs::copy_file(From: InterfaceFile, To: Path.str())))
529 reportWarning(Warning: Twine("cannot copy parseable Swift interface ") +
530 InterfaceFile + ": " + toString(E: errorCodeToError(EC)));
531 Path.resize(N: BaseLength);
532 }
533 return Error::success();
534}
535
536void DwarfLinkerForBinary::copySwiftReflectionMetadata(
537 const llvm::dsymutil::DebugMapObject *Obj, classic::DwarfStreamer *Streamer,
538 std::vector<uint64_t> &SectionToOffsetInDwarf,
539 std::vector<MachOUtils::DwarfRelocationApplicationInfo>
540 &RelocationsToApply) {
541 using binaryformat::Swift5ReflectionSectionKind;
542 auto OF =
543 llvm::object::ObjectFile::createObjectFile(ObjectPath: Obj->getObjectFilename());
544 if (!OF) {
545 llvm::consumeError(Err: OF.takeError());
546 return;
547 }
548 if (auto *MO = dyn_cast<llvm::object::MachOObjectFile>(Val: OF->getBinary())) {
549 // Collect the swift reflection sections before emitting them. This is
550 // done so we control the order they're emitted.
551 std::array<std::optional<object::SectionRef>,
552 Swift5ReflectionSectionKind::last + 1>
553 SwiftSections;
554 for (auto &Section : MO->sections()) {
555 llvm::Expected<llvm::StringRef> NameOrErr =
556 MO->getSectionName(Sec: Section.getRawDataRefImpl());
557 if (!NameOrErr) {
558 llvm::consumeError(Err: NameOrErr.takeError());
559 continue;
560 }
561 NameOrErr->consume_back(Suffix: "__TEXT");
562 auto ReflSectionKind =
563 MO->mapReflectionSectionNameToEnumValue(SectionName: *NameOrErr);
564 if (MO->isReflectionSectionStrippable(ReflectionSectionKind: ReflSectionKind))
565 SwiftSections[ReflSectionKind] = Section;
566 }
567 // Make sure we copy the sections in alphabetic order.
568 auto SectionKindsToEmit = {Swift5ReflectionSectionKind::assocty,
569 Swift5ReflectionSectionKind::fieldmd,
570 Swift5ReflectionSectionKind::reflstr};
571 for (auto SectionKind : SectionKindsToEmit) {
572 if (!SwiftSections[SectionKind])
573 continue;
574 auto &Section = *SwiftSections[SectionKind];
575 llvm::Expected<llvm::StringRef> SectionContents = Section.getContents();
576 if (!SectionContents)
577 continue;
578 const auto *MO =
579 llvm::cast<llvm::object::MachOObjectFile>(Val: Section.getObject());
580 collectRelocationsToApplyToSwiftReflectionSections(
581 Section, Contents&: *SectionContents, MO, SectionToOffsetInDwarf, Obj,
582 RelocationsToApply);
583 // Update the section start with the current section's contribution, so
584 // the next section we copy from a different .o file points to the correct
585 // place.
586 SectionToOffsetInDwarf[SectionKind] += Section.getSize();
587 Streamer->emitSwiftReflectionSection(ReflSectionKind: SectionKind, Buffer: *SectionContents,
588 Alignment: Section.getAlignment().value(),
589 Size: Section.getSize());
590 }
591 }
592}
593
594bool DwarfLinkerForBinary::link(const DebugMap &Map) {
595 if (Options.DWARFLinkerType == DsymutilDWARFLinkerType::Parallel)
596 return linkImpl<parallel::DWARFLinker>(Map, ObjectType: Options.FileType);
597
598 return linkImpl<classic::DWARFLinker>(Map, ObjectType: Options.FileType);
599}
600
601template <typename Linker>
602void setAcceleratorTables(Linker &GeneralLinker,
603 DsymutilAccelTableKind TableKind,
604 uint16_t MaxDWARFVersion) {
605 switch (TableKind) {
606 case DsymutilAccelTableKind::Apple:
607 GeneralLinker.addAccelTableKind(Linker::AccelTableKind::Apple);
608 return;
609 case DsymutilAccelTableKind::Dwarf:
610 GeneralLinker.addAccelTableKind(Linker::AccelTableKind::DebugNames);
611 return;
612 case DsymutilAccelTableKind::Pub:
613 GeneralLinker.addAccelTableKind(Linker::AccelTableKind::Pub);
614 return;
615 case DsymutilAccelTableKind::Default:
616 if (MaxDWARFVersion >= 5)
617 GeneralLinker.addAccelTableKind(Linker::AccelTableKind::DebugNames);
618 else
619 GeneralLinker.addAccelTableKind(Linker::AccelTableKind::Apple);
620 return;
621 case DsymutilAccelTableKind::None:
622 // Nothing to do.
623 return;
624 }
625
626 llvm_unreachable("All cases handled above!");
627}
628
629template <typename Linker>
630bool DwarfLinkerForBinary::linkImpl(
631 const DebugMap &Map, typename Linker::OutputFileType ObjectType) {
632
633 std::vector<ObjectWithRelocMap> ObjectsForLinking;
634
635 DebugMap DebugMap(Map.getTriple(), Map.getBinaryPath());
636
637 std::unique_ptr<Linker> GeneralLinker = Linker::createLinker(
638 [&](const Twine &Error, StringRef Context, const DWARFDie *DIE) {
639 reportError(Error, Context, DIE);
640 },
641 [&](const Twine &Warning, StringRef Context, const DWARFDie *DIE) {
642 reportWarning(Warning, Context, DIE);
643 });
644
645 std::unique_ptr<classic::DwarfStreamer> Streamer;
646 if (!Options.NoOutput) {
647 if (Expected<std::unique_ptr<classic::DwarfStreamer>> StreamerOrErr =
648 classic::DwarfStreamer::createStreamer(
649 TheTriple: Map.getTriple(), FileType: ObjectType, OutFile,
650 Warning: [&](const Twine &Warning, StringRef Context,
651 const DWARFDie *DIE) {
652 reportWarning(Warning, Context, DIE);
653 }))
654 Streamer = std::move(*StreamerOrErr);
655 else {
656 handleAllErrors(StreamerOrErr.takeError(), [&](const ErrorInfoBase &EI) {
657 reportError(Error: EI.message(), Context: "dwarf streamer init");
658 });
659 return false;
660 }
661
662 if constexpr (std::is_same<Linker, parallel::DWARFLinker>::value) {
663 GeneralLinker->setOutputDWARFHandler(
664 Map.getTriple(),
665 [&](std::shared_ptr<parallel::SectionDescriptorBase> Section) {
666 Streamer->emitSectionContents(SecData: Section->getContents(),
667 SecKind: Section->getKind());
668 });
669 } else
670 GeneralLinker->setOutputDWARFEmitter(Streamer.get());
671 }
672
673 remarks::RemarkLinker RL;
674 if (!Options.RemarksPrependPath.empty())
675 RL.setExternalFilePrependPath(Options.RemarksPrependPath);
676 RL.setKeepAllRemarks(Options.RemarksKeepAll);
677 GeneralLinker->setObjectPrefixMap(&Options.ObjectPrefixMap);
678
679 GeneralLinker->setVerbosity(Options.Verbose);
680 GeneralLinker->setStatistics(Options.Statistics);
681 GeneralLinker->setVerifyInputDWARF(Options.VerifyInputDWARF);
682 GeneralLinker->setNoODR(Options.NoODR);
683 GeneralLinker->setUpdateIndexTablesOnly(Options.Update);
684 GeneralLinker->setNumThreads(Options.Threads);
685 GeneralLinker->setPrependPath(Options.PrependPath);
686 GeneralLinker->setKeepFunctionForStatic(Options.KeepFunctionForStatic);
687 GeneralLinker->setInputVerificationHandler(
688 [&](const DWARFFile &File, llvm::StringRef Output) {
689 std::lock_guard<std::mutex> Guard(ErrorHandlerMutex);
690 if (Options.Verbose)
691 errs() << Output;
692 warn(Warning: "input verification failed", Context: File.FileName);
693 HasVerificationErrors = true;
694 });
695 auto Loader = [&](StringRef ContainerName,
696 StringRef Path) -> ErrorOr<DWARFFile &> {
697 auto &Obj = DebugMap.addDebugMapObject(
698 ObjectFilePath: Path, Timestamp: sys::TimePoint<std::chrono::seconds>(), Type: MachO::N_OSO);
699
700 auto DLBRelocMap = std::make_shared<DwarfLinkerForBinaryRelocationMap>();
701 if (ErrorOr<std::unique_ptr<DWARFFile>> ErrorOrObj =
702 loadObject(Obj, DebugMap, RL, DLBRM: DLBRelocMap)) {
703 ObjectsForLinking.emplace_back(args: std::move(*ErrorOrObj), args&: DLBRelocMap);
704 return *ObjectsForLinking.back().Object;
705 } else {
706 // Try and emit more helpful warnings by applying some heuristics.
707 StringRef ObjFile = ContainerName;
708 bool IsClangModule = sys::path::extension(path: Path) == ".pcm";
709 bool IsArchive = ObjFile.ends_with(Suffix: ")");
710
711 if (IsClangModule) {
712 StringRef ModuleCacheDir = sys::path::parent_path(path: Path);
713 if (sys::fs::exists(Path: ModuleCacheDir)) {
714 // If the module's parent directory exists, we assume that the
715 // module cache has expired and was pruned by clang. A more
716 // adventurous dsymutil would invoke clang to rebuild the module
717 // now.
718 if (!ModuleCacheHintDisplayed) {
719 WithColor::note()
720 << "The clang module cache may have expired since "
721 "this object file was built. Rebuilding the "
722 "object file will rebuild the module cache.\n";
723 ModuleCacheHintDisplayed = true;
724 }
725 } else if (IsArchive) {
726 // If the module cache directory doesn't exist at all and the
727 // object file is inside a static library, we assume that the
728 // static library was built on a different machine. We don't want
729 // to discourage module debugging for convenience libraries within
730 // a project though.
731 if (!ArchiveHintDisplayed) {
732 WithColor::note()
733 << "Linking a static library that was built with "
734 "-gmodules, but the module cache was not found. "
735 "Redistributable static libraries should never be "
736 "built with module debugging enabled. The debug "
737 "experience will be degraded due to incomplete "
738 "debug information.\n";
739 ArchiveHintDisplayed = true;
740 }
741 }
742 }
743
744 return ErrorOrObj.getError();
745 }
746
747 llvm_unreachable("Unhandled DebugMap object");
748 };
749 GeneralLinker->setSwiftInterfacesMap(&ParseableSwiftInterfaces);
750 bool ReflectionSectionsPresentInBinary = false;
751 // If there is no output specified, no point in checking the binary for swift5
752 // reflection sections.
753 if (!Options.NoOutput) {
754 ReflectionSectionsPresentInBinary =
755 binaryHasStrippableSwiftReflectionSections(Map, Options, BinHolder);
756 }
757
758 std::vector<MachOUtils::DwarfRelocationApplicationInfo> RelocationsToApply;
759 if (!Options.NoOutput && !ReflectionSectionsPresentInBinary) {
760 auto SectionToOffsetInDwarf =
761 calculateStartOfStrippableReflectionSections(Map);
762 for (const auto &Obj : Map.objects())
763 copySwiftReflectionMetadata(Obj: Obj.get(), Streamer: Streamer.get(),
764 SectionToOffsetInDwarf, RelocationsToApply);
765 }
766
767 uint16_t MaxDWARFVersion = 0;
768 std::function<void(const DWARFUnit &Unit)> OnCUDieLoaded =
769 [&MaxDWARFVersion](const DWARFUnit &Unit) {
770 MaxDWARFVersion = std::max(a: Unit.getVersion(), b: MaxDWARFVersion);
771 };
772
773 llvm::StringSet<> SwiftModules;
774 for (const auto &Obj : Map.objects()) {
775 // N_AST objects (swiftmodule files) should get dumped directly into the
776 // appropriate DWARF section.
777 if (Obj->getType() == MachO::N_AST) {
778 if (Options.Verbose)
779 outs() << "DEBUG MAP OBJECT: " << Obj->getObjectFilename() << "\n";
780
781 StringRef File = Obj->getObjectFilename();
782 if (!SwiftModules.insert(key: File).second)
783 continue;
784
785 auto ErrorOrMem = MemoryBuffer::getFile(Filename: File);
786 if (!ErrorOrMem) {
787 reportWarning(Warning: "Could not open '" + File + "'");
788 continue;
789 }
790 auto FromInterfaceOrErr =
791 IsBuiltFromSwiftInterface(data: (*ErrorOrMem)->getBuffer());
792 if (!FromInterfaceOrErr) {
793 reportWarning(Warning: "Could not parse binary Swift module: " +
794 toString(E: FromInterfaceOrErr.takeError()),
795 Context: Obj->getObjectFilename());
796 // Only skip swiftmodules that could be parsed and are positively
797 // identified as textual. Do so only when the option allows.
798 } else if (*FromInterfaceOrErr &&
799 !Options.IncludeSwiftModulesFromInterface) {
800 if (Options.Verbose)
801 outs() << "Skipping compiled textual Swift interface: "
802 << Obj->getObjectFilename() << "\n";
803 continue;
804 }
805
806 sys::fs::file_status Stat;
807 if (auto Err = sys::fs::status(path: File, result&: Stat)) {
808 reportWarning(Warning: Err.message());
809 continue;
810 }
811 if (!Options.NoTimestamp) {
812 // The modification can have sub-second precision so we need to cast
813 // away the extra precision that's not present in the debug map.
814 auto ModificationTime =
815 std::chrono::time_point_cast<std::chrono::seconds>(
816 t: Stat.getLastModificationTime());
817 if (Obj->getTimestamp() != sys::TimePoint<>() &&
818 ModificationTime != Obj->getTimestamp()) {
819 // Not using the helper here as we can easily stream TimePoint<>.
820 WithColor::warning()
821 << File << ": timestamp mismatch between swift interface file ("
822 << sys::TimePoint<>(ModificationTime) << ") and debug map ("
823 << sys::TimePoint<>(Obj->getTimestamp()) << ")\n";
824 continue;
825 }
826 }
827
828 // Copy the module into the .swift_ast section.
829 if (!Options.NoOutput)
830 Streamer->emitSwiftAST(Buffer: (*ErrorOrMem)->getBuffer());
831
832 continue;
833 }
834
835 auto DLBRelocMap = std::make_shared<DwarfLinkerForBinaryRelocationMap>();
836 if (ErrorOr<std::unique_ptr<DWARFFile>> ErrorOrObj =
837 loadObject(Obj: *Obj, DebugMap: Map, RL, DLBRM: DLBRelocMap)) {
838 ObjectsForLinking.emplace_back(args: std::move(*ErrorOrObj), args&: DLBRelocMap);
839 GeneralLinker->addObjectFile(*ObjectsForLinking.back().Object, Loader,
840 OnCUDieLoaded);
841 } else {
842 ObjectsForLinking.push_back(
843 x: {std::make_unique<DWARFFile>(args: Obj->getObjectFilename(), args: nullptr,
844 args: nullptr),
845 DLBRelocMap});
846 GeneralLinker->addObjectFile(*ObjectsForLinking.back().Object);
847 }
848 }
849
850 // If we haven't seen any CUs, pick an arbitrary valid Dwarf version anyway.
851 if (MaxDWARFVersion == 0)
852 MaxDWARFVersion = 3;
853
854 if (Error E = GeneralLinker->setTargetDWARFVersion(MaxDWARFVersion))
855 return error(Error: toString(E: std::move(E)));
856
857 setAcceleratorTables<Linker>(*GeneralLinker, Options.TheAccelTableKind,
858 MaxDWARFVersion);
859
860 // link debug info for loaded object files.
861 if (Error E = GeneralLinker->link())
862 return error(Error: toString(E: std::move(E)));
863
864 StringRef ArchName = Map.getTriple().getArchName();
865 if (Error E = emitRemarks(Options, BinaryPath: Map.getBinaryPath(), ArchName, RL))
866 return error(Error: toString(E: std::move(E)));
867
868 if (Options.NoOutput)
869 return true;
870
871 if (Error E = emitRelocations(DM: Map, ObjectsForLinking))
872 return error(Error: toString(E: std::move(E)));
873
874 if (Options.ResourceDir && !ParseableSwiftInterfaces.empty()) {
875 StringRef ArchName = Triple::getArchTypeName(Kind: Map.getTriple().getArch());
876 if (auto E = copySwiftInterfaces(Architecture: ArchName))
877 return error(Error: toString(E: std::move(E)));
878 }
879
880 auto MapTriple = Map.getTriple();
881 if ((MapTriple.isOSDarwin() || MapTriple.isOSBinFormatMachO()) &&
882 !Map.getBinaryPath().empty() &&
883 ObjectType == Linker::OutputFileType::Object)
884 return MachOUtils::generateDsymCompanion(
885 VFS: Options.VFS, DM: Map, MS&: *Streamer->getAsmPrinter().OutStreamer, OutFile,
886 RelocationsToApply, AllowSectionHeaderOffsetOverflow: Options.AllowSectionHeaderOffsetOverflow);
887
888 Streamer->finish();
889 return true;
890}
891
892/// Iterate over the relocations of the given \p Section and
893/// store the ones that correspond to debug map entries into the
894/// ValidRelocs array.
895void DwarfLinkerForBinary::AddressManager::findValidRelocsMachO(
896 const object::SectionRef &Section, const object::MachOObjectFile &Obj,
897 const DebugMapObject &DMO, std::vector<ValidReloc> &ValidRelocs) {
898 Expected<StringRef> ContentsOrErr = Section.getContents();
899 if (!ContentsOrErr) {
900 consumeError(Err: ContentsOrErr.takeError());
901 Linker.reportWarning(Warning: "error reading section", Context: DMO.getObjectFilename());
902 return;
903 }
904 DataExtractor Data(*ContentsOrErr, Obj.isLittleEndian(), 0);
905 bool SkipNext = false;
906
907 for (const object::RelocationRef &Reloc : Section.relocations()) {
908 if (SkipNext) {
909 SkipNext = false;
910 continue;
911 }
912
913 object::DataRefImpl RelocDataRef = Reloc.getRawDataRefImpl();
914 MachO::any_relocation_info MachOReloc = Obj.getRelocation(Rel: RelocDataRef);
915
916 if (object::MachOObjectFile::isMachOPairedReloc(RelocType: Obj.getAnyRelocationType(RE: MachOReloc),
917 Arch: Obj.getArch())) {
918 SkipNext = true;
919 Linker.reportWarning(Warning: "unsupported relocation in " + *Section.getName() +
920 " section.",
921 Context: DMO.getObjectFilename());
922 continue;
923 }
924
925 unsigned RelocSize = 1 << Obj.getAnyRelocationLength(RE: MachOReloc);
926 uint64_t Offset64 = Reloc.getOffset();
927 if ((RelocSize != 4 && RelocSize != 8)) {
928 Linker.reportWarning(Warning: "unsupported relocation in " + *Section.getName() +
929 " section.",
930 Context: DMO.getObjectFilename());
931 continue;
932 }
933 uint64_t OffsetCopy = Offset64;
934 // Mach-o uses REL relocations, the addend is at the relocation offset.
935 uint64_t Addend = Data.getUnsigned(offset_ptr: &OffsetCopy, byte_size: RelocSize);
936 uint64_t SymAddress;
937 int64_t SymOffset;
938
939 if (Obj.isRelocationScattered(RE: MachOReloc)) {
940 // The address of the base symbol for scattered relocations is
941 // stored in the reloc itself. The actual addend will store the
942 // base address plus the offset.
943 SymAddress = Obj.getScatteredRelocationValue(RE: MachOReloc);
944 SymOffset = int64_t(Addend) - SymAddress;
945 } else {
946 SymAddress = Addend;
947 SymOffset = 0;
948 }
949
950 auto Sym = Reloc.getSymbol();
951 if (Sym != Obj.symbol_end()) {
952 Expected<StringRef> SymbolName = Sym->getName();
953 if (!SymbolName) {
954 consumeError(Err: SymbolName.takeError());
955 Linker.reportWarning(Warning: "error getting relocation symbol name.",
956 Context: DMO.getObjectFilename());
957 continue;
958 }
959 if (const auto *Mapping = DMO.lookupSymbol(SymbolName: *SymbolName))
960 ValidRelocs.emplace_back(args&: Offset64, args&: RelocSize, args&: Addend, args: Mapping->getKey(),
961 args: Mapping->getValue());
962 } else if (const auto *Mapping = DMO.lookupObjectAddress(Address: SymAddress)) {
963 // Do not store the addend. The addend was the address of the symbol in
964 // the object file, the address in the binary that is stored in the debug
965 // map doesn't need to be offset.
966 ValidRelocs.emplace_back(args&: Offset64, args&: RelocSize, args&: SymOffset,
967 args: Mapping->getKey(), args: Mapping->getValue());
968 }
969 }
970}
971
972/// Dispatch the valid relocation finding logic to the
973/// appropriate handler depending on the object file format.
974bool DwarfLinkerForBinary::AddressManager::findValidRelocs(
975 const object::SectionRef &Section, const object::ObjectFile &Obj,
976 const DebugMapObject &DMO, std::vector<ValidReloc> &Relocs) {
977 // Dispatch to the right handler depending on the file type.
978 if (auto *MachOObj = dyn_cast<object::MachOObjectFile>(Val: &Obj))
979 findValidRelocsMachO(Section, Obj: *MachOObj, DMO, ValidRelocs&: Relocs);
980 else
981 Linker.reportWarning(Warning: Twine("unsupported object file type: ") +
982 Obj.getFileName(),
983 Context: DMO.getObjectFilename());
984 if (Relocs.empty())
985 return false;
986
987 // Sort the relocations by offset. We will walk the DIEs linearly in
988 // the file, this allows us to just keep an index in the relocation
989 // array that we advance during our walk, rather than resorting to
990 // some associative container. See DwarfLinkerForBinary::NextValidReloc.
991 llvm::sort(C&: Relocs);
992 return true;
993}
994
995/// Look for relocations in the debug_info and debug_addr section that match
996/// entries in the debug map. These relocations will drive the Dwarf link by
997/// indicating which DIEs refer to symbols present in the linked binary.
998/// \returns whether there are any valid relocations in the debug info.
999bool DwarfLinkerForBinary::AddressManager::findValidRelocsInDebugSections(
1000 const object::ObjectFile &Obj, const DebugMapObject &DMO) {
1001 // Find the debug_info section.
1002 bool FoundValidRelocs = false;
1003 for (const object::SectionRef &Section : Obj.sections()) {
1004 StringRef SectionName;
1005 if (Expected<StringRef> NameOrErr = Section.getName())
1006 SectionName = *NameOrErr;
1007 else
1008 consumeError(Err: NameOrErr.takeError());
1009
1010 SectionName = SectionName.substr(Start: SectionName.find_first_not_of(Chars: "._"));
1011 if (SectionName == "debug_info")
1012 FoundValidRelocs |=
1013 findValidRelocs(Section, Obj, DMO, Relocs&: ValidDebugInfoRelocs);
1014 if (SectionName == "debug_addr")
1015 FoundValidRelocs |=
1016 findValidRelocs(Section, Obj, DMO, Relocs&: ValidDebugAddrRelocs);
1017 }
1018 return FoundValidRelocs;
1019}
1020
1021std::vector<ValidReloc> DwarfLinkerForBinary::AddressManager::getRelocations(
1022 const std::vector<ValidReloc> &Relocs, uint64_t StartPos, uint64_t EndPos) {
1023 std::vector<ValidReloc> Res;
1024
1025 auto CurReloc = partition_point(Range: Relocs, P: [StartPos](const ValidReloc &Reloc) {
1026 return (uint64_t)Reloc.Offset < StartPos;
1027 });
1028
1029 while (CurReloc != Relocs.end() && CurReloc->Offset >= StartPos &&
1030 (uint64_t)CurReloc->Offset < EndPos) {
1031 Res.push_back(x: *CurReloc);
1032 CurReloc++;
1033 }
1034
1035 return Res;
1036}
1037
1038void DwarfLinkerForBinary::AddressManager::printReloc(const ValidReloc &Reloc) {
1039 const auto &Mapping = Reloc.SymbolMapping;
1040 const uint64_t ObjectAddress = Mapping.ObjectAddress
1041 ? uint64_t(*Mapping.ObjectAddress)
1042 : std::numeric_limits<uint64_t>::max();
1043
1044 outs() << "Found valid debug map entry: " << Reloc.SymbolName << "\t"
1045 << format(Fmt: "0x%016" PRIx64 " => 0x%016" PRIx64 "\n", Vals: ObjectAddress,
1046 Vals: uint64_t(Mapping.BinaryAddress));
1047}
1048
1049int64_t
1050DwarfLinkerForBinary::AddressManager::getRelocValue(const ValidReloc &Reloc) {
1051 int64_t AddrAdjust = relocate(Reloc);
1052 if (Reloc.SymbolMapping.ObjectAddress)
1053 AddrAdjust -= uint64_t(*Reloc.SymbolMapping.ObjectAddress);
1054 return AddrAdjust;
1055}
1056
1057std::optional<int64_t>
1058DwarfLinkerForBinary::AddressManager::hasValidRelocationAt(
1059 const std::vector<ValidReloc> &AllRelocs, uint64_t StartOffset,
1060 uint64_t EndOffset, bool Verbose) {
1061 std::vector<ValidReloc> Relocs =
1062 getRelocations(Relocs: AllRelocs, StartPos: StartOffset, EndPos: EndOffset);
1063 if (Relocs.size() == 0)
1064 return std::nullopt;
1065
1066 if (Verbose)
1067 printReloc(Reloc: Relocs[0]);
1068
1069 return getRelocValue(Reloc: Relocs[0]);
1070}
1071
1072/// Get the starting and ending (exclusive) offset for the
1073/// attribute with index \p Idx descibed by \p Abbrev. \p Offset is
1074/// supposed to point to the position of the first attribute described
1075/// by \p Abbrev.
1076/// \return [StartOffset, EndOffset) as a pair.
1077static std::pair<uint64_t, uint64_t>
1078getAttributeOffsets(const DWARFAbbreviationDeclaration *Abbrev, unsigned Idx,
1079 uint64_t Offset, const DWARFUnit &Unit) {
1080 DataExtractor Data = Unit.getDebugInfoExtractor();
1081
1082 for (unsigned I = 0; I < Idx; ++I)
1083 DWARFFormValue::skipValue(Form: Abbrev->getFormByIndex(idx: I), DebugInfoData: Data, OffsetPtr: &Offset,
1084 FormParams: Unit.getFormParams());
1085
1086 uint64_t End = Offset;
1087 DWARFFormValue::skipValue(Form: Abbrev->getFormByIndex(idx: Idx), DebugInfoData: Data, OffsetPtr: &End,
1088 FormParams: Unit.getFormParams());
1089
1090 return std::make_pair(x&: Offset, y&: End);
1091}
1092
1093std::optional<int64_t>
1094DwarfLinkerForBinary::AddressManager::getExprOpAddressRelocAdjustment(
1095 DWARFUnit &U, const DWARFExpression::Operation &Op, uint64_t StartOffset,
1096 uint64_t EndOffset, bool Verbose) {
1097 switch (Op.getCode()) {
1098 default: {
1099 assert(false && "Specified operation does not have address operand");
1100 } break;
1101 case dwarf::DW_OP_const2u:
1102 case dwarf::DW_OP_const4u:
1103 case dwarf::DW_OP_const8u:
1104 case dwarf::DW_OP_const2s:
1105 case dwarf::DW_OP_const4s:
1106 case dwarf::DW_OP_const8s:
1107 case dwarf::DW_OP_addr: {
1108 return hasValidRelocationAt(AllRelocs: ValidDebugInfoRelocs, StartOffset, EndOffset,
1109 Verbose);
1110 } break;
1111 case dwarf::DW_OP_constx:
1112 case dwarf::DW_OP_addrx: {
1113 return hasValidRelocationAt(AllRelocs: ValidDebugAddrRelocs, StartOffset, EndOffset,
1114 Verbose);
1115 } break;
1116 }
1117
1118 return std::nullopt;
1119}
1120
1121std::optional<int64_t>
1122DwarfLinkerForBinary::AddressManager::getSubprogramRelocAdjustment(
1123 const DWARFDie &DIE, bool Verbose) {
1124 const auto *Abbrev = DIE.getAbbreviationDeclarationPtr();
1125
1126 std::optional<uint32_t> LowPcIdx =
1127 Abbrev->findAttributeIndex(attr: dwarf::DW_AT_low_pc);
1128 if (!LowPcIdx)
1129 return std::nullopt;
1130
1131 dwarf::Form Form = Abbrev->getFormByIndex(idx: *LowPcIdx);
1132
1133 switch (Form) {
1134 case dwarf::DW_FORM_addr: {
1135 uint64_t Offset = DIE.getOffset() + getULEB128Size(Value: Abbrev->getCode());
1136 uint64_t LowPcOffset, LowPcEndOffset;
1137 std::tie(args&: LowPcOffset, args&: LowPcEndOffset) =
1138 getAttributeOffsets(Abbrev, Idx: *LowPcIdx, Offset, Unit: *DIE.getDwarfUnit());
1139 return hasValidRelocationAt(AllRelocs: ValidDebugInfoRelocs, StartOffset: LowPcOffset,
1140 EndOffset: LowPcEndOffset, Verbose);
1141 }
1142 case dwarf::DW_FORM_addrx:
1143 case dwarf::DW_FORM_addrx1:
1144 case dwarf::DW_FORM_addrx2:
1145 case dwarf::DW_FORM_addrx3:
1146 case dwarf::DW_FORM_addrx4: {
1147 std::optional<DWARFFormValue> AddrValue = DIE.find(Attr: dwarf::DW_AT_low_pc);
1148 if (std::optional<uint64_t> AddressOffset =
1149 DIE.getDwarfUnit()->getIndexedAddressOffset(
1150 Index: AddrValue->getRawUValue()))
1151 return hasValidRelocationAt(
1152 AllRelocs: ValidDebugAddrRelocs, StartOffset: *AddressOffset,
1153 EndOffset: *AddressOffset + DIE.getDwarfUnit()->getAddressByteSize(), Verbose);
1154
1155 Linker.reportWarning(Warning: "no base offset for address table", Context: SrcFileName);
1156 return std::nullopt;
1157 }
1158 default:
1159 return std::nullopt;
1160 }
1161}
1162
1163std::optional<StringRef>
1164DwarfLinkerForBinary::AddressManager::getLibraryInstallName() {
1165 return LibInstallName;
1166}
1167
1168uint64_t
1169DwarfLinkerForBinary::AddressManager::relocate(const ValidReloc &Reloc) const {
1170 return Reloc.SymbolMapping.BinaryAddress + Reloc.Addend;
1171}
1172
1173void DwarfLinkerForBinary::AddressManager::updateAndSaveValidRelocs(
1174 bool IsDWARF5, uint64_t OriginalUnitOffset, int64_t LinkedOffset,
1175 uint64_t StartOffset, uint64_t EndOffset) {
1176 std::vector<ValidReloc> InRelocs =
1177 getRelocations(Relocs: ValidDebugInfoRelocs, StartPos: StartOffset, EndPos: EndOffset);
1178 if (IsDWARF5)
1179 InRelocs = getRelocations(Relocs: ValidDebugAddrRelocs, StartPos: StartOffset, EndPos: EndOffset);
1180 DwarfLinkerRelocMap->updateAndSaveValidRelocs(
1181 IsDWARF5, InRelocs, UnitOffset: OriginalUnitOffset, LinkedOffset);
1182}
1183
1184void DwarfLinkerForBinary::AddressManager::updateRelocationsWithUnitOffset(
1185 uint64_t OriginalUnitOffset, uint64_t OutputUnitOffset) {
1186 DwarfLinkerRelocMap->updateRelocationsWithUnitOffset(OriginalUnitOffset,
1187 OutputUnitOffset);
1188}
1189/// Apply the valid relocations found by findValidRelocs() to
1190/// the buffer \p Data, taking into account that Data is at \p BaseOffset
1191/// in the debug_info section.
1192///
1193/// Like for findValidRelocs(), this function must be called with
1194/// monotonic \p BaseOffset values.
1195///
1196/// \returns whether any reloc has been applied.
1197bool DwarfLinkerForBinary::AddressManager::applyValidRelocs(
1198 MutableArrayRef<char> Data, uint64_t BaseOffset, bool IsLittleEndian) {
1199
1200 std::vector<ValidReloc> Relocs = getRelocations(
1201 Relocs: ValidDebugInfoRelocs, StartPos: BaseOffset, EndPos: BaseOffset + Data.size());
1202
1203 for (const ValidReloc &CurReloc : Relocs) {
1204 assert(CurReloc.Offset - BaseOffset < Data.size());
1205 assert(CurReloc.Offset - BaseOffset + CurReloc.Size <= Data.size());
1206 char Buf[8];
1207 uint64_t Value = relocate(Reloc: CurReloc);
1208 for (unsigned I = 0; I != CurReloc.Size; ++I) {
1209 unsigned Index = IsLittleEndian ? I : (CurReloc.Size - I - 1);
1210 Buf[I] = uint8_t(Value >> (Index * 8));
1211 }
1212 assert(CurReloc.Size <= sizeof(Buf));
1213 memcpy(dest: &Data[CurReloc.Offset - BaseOffset], src: Buf, n: CurReloc.Size);
1214 }
1215 return Relocs.size() > 0;
1216}
1217
1218void DwarfLinkerForBinaryRelocationMap::init(DWARFContext &Context) {
1219 for (const std::unique_ptr<DWARFUnit> &CU : Context.compile_units())
1220 StoredValidDebugInfoRelocsMap.insert(
1221 KV: std::make_pair(x: CU->getOffset(), y: std::vector<ValidReloc>()));
1222 // FIXME: Support relocations debug_addr (DWARF5).
1223}
1224
1225void DwarfLinkerForBinaryRelocationMap::addValidRelocs(RelocationMap &RM) {
1226 for (const auto &DebugInfoRelocs : StoredValidDebugInfoRelocsMap) {
1227 for (const auto &InfoReloc : DebugInfoRelocs.second)
1228 RM.addRelocationMapEntry(Relocation: InfoReloc);
1229 }
1230 // FIXME: Support relocations debug_addr (DWARF5).
1231}
1232
1233void DwarfLinkerForBinaryRelocationMap::updateRelocationsWithUnitOffset(
1234 uint64_t OriginalUnitOffset, uint64_t OutputUnitOffset) {
1235 std::vector<ValidReloc> &StoredValidDebugInfoRelocs =
1236 StoredValidDebugInfoRelocsMap[OriginalUnitOffset];
1237 for (ValidReloc &R : StoredValidDebugInfoRelocs) {
1238 R.Offset = (uint64_t)R.Offset + OutputUnitOffset;
1239 }
1240 // FIXME: Support relocations debug_addr (DWARF5).
1241}
1242
1243void DwarfLinkerForBinaryRelocationMap::updateAndSaveValidRelocs(
1244 bool IsDWARF5, std::vector<ValidReloc> &InRelocs, uint64_t UnitOffset,
1245 int64_t LinkedOffset) {
1246 std::vector<ValidReloc> &OutRelocs =
1247 StoredValidDebugInfoRelocsMap[UnitOffset];
1248 if (IsDWARF5)
1249 OutRelocs = StoredValidDebugAddrRelocsMap[UnitOffset];
1250
1251 for (ValidReloc &R : InRelocs) {
1252 OutRelocs.emplace_back(args: R.Offset + LinkedOffset, args&: R.Size, args&: R.Addend,
1253 args&: R.SymbolName, args&: R.SymbolMapping);
1254 }
1255}
1256
1257} // namespace dsymutil
1258} // namespace llvm
1259