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 "dsymutil.h" |
14 | #include "llvm/ADT/ArrayRef.h" |
15 | #include "llvm/ADT/DenseMap.h" |
16 | #include "llvm/ADT/FoldingSet.h" |
17 | #include "llvm/ADT/Hashing.h" |
18 | #include "llvm/ADT/STLExtras.h" |
19 | #include "llvm/ADT/SmallString.h" |
20 | #include "llvm/ADT/StringRef.h" |
21 | #include "llvm/ADT/Twine.h" |
22 | #include "llvm/BinaryFormat/Dwarf.h" |
23 | #include "llvm/BinaryFormat/MachO.h" |
24 | #include "llvm/BinaryFormat/Swift.h" |
25 | #include "llvm/CodeGen/AccelTable.h" |
26 | #include "llvm/CodeGen/AsmPrinter.h" |
27 | #include "llvm/CodeGen/DIE.h" |
28 | #include "llvm/CodeGen/NonRelocatableStringpool.h" |
29 | #include "llvm/Config/config.h" |
30 | #include "llvm/DWARFLinker/Classic/DWARFLinker.h" |
31 | #include "llvm/DWARFLinker/Classic/DWARFStreamer.h" |
32 | #include "llvm/DWARFLinker/Parallel/DWARFLinker.h" |
33 | #include "llvm/DebugInfo/DIContext.h" |
34 | #include "llvm/DebugInfo/DWARF/DWARFAbbreviationDeclaration.h" |
35 | #include "llvm/DebugInfo/DWARF/DWARFContext.h" |
36 | #include "llvm/DebugInfo/DWARF/DWARFDataExtractor.h" |
37 | #include "llvm/DebugInfo/DWARF/DWARFDebugLine.h" |
38 | #include "llvm/DebugInfo/DWARF/DWARFDebugRangeList.h" |
39 | #include "llvm/DebugInfo/DWARF/DWARFDie.h" |
40 | #include "llvm/DebugInfo/DWARF/DWARFExpression.h" |
41 | #include "llvm/DebugInfo/DWARF/DWARFFormValue.h" |
42 | #include "llvm/DebugInfo/DWARF/DWARFSection.h" |
43 | #include "llvm/DebugInfo/DWARF/DWARFUnit.h" |
44 | #include "llvm/MC/MCAsmBackend.h" |
45 | #include "llvm/MC/MCAsmInfo.h" |
46 | #include "llvm/MC/MCCodeEmitter.h" |
47 | #include "llvm/MC/MCContext.h" |
48 | #include "llvm/MC/MCDwarf.h" |
49 | #include "llvm/MC/MCInstrInfo.h" |
50 | #include "llvm/MC/MCObjectFileInfo.h" |
51 | #include "llvm/MC/MCObjectWriter.h" |
52 | #include "llvm/MC/MCRegisterInfo.h" |
53 | #include "llvm/MC/MCSection.h" |
54 | #include "llvm/MC/MCStreamer.h" |
55 | #include "llvm/MC/MCSubtargetInfo.h" |
56 | #include "llvm/MC/MCTargetOptions.h" |
57 | #include "llvm/MC/MCTargetOptionsCommandFlags.h" |
58 | #include "llvm/MC/TargetRegistry.h" |
59 | #include "llvm/Object/MachO.h" |
60 | #include "llvm/Object/ObjectFile.h" |
61 | #include "llvm/Object/SymbolicFile.h" |
62 | #include "llvm/Support/Allocator.h" |
63 | #include "llvm/Support/Casting.h" |
64 | #include "llvm/Support/Compiler.h" |
65 | #include "llvm/Support/DJB.h" |
66 | #include "llvm/Support/DataExtractor.h" |
67 | #include "llvm/Support/Error.h" |
68 | #include "llvm/Support/ErrorHandling.h" |
69 | #include "llvm/Support/ErrorOr.h" |
70 | #include "llvm/Support/FileSystem.h" |
71 | #include "llvm/Support/Format.h" |
72 | #include "llvm/Support/LEB128.h" |
73 | #include "llvm/Support/MathExtras.h" |
74 | #include "llvm/Support/MemoryBuffer.h" |
75 | #include "llvm/Support/Path.h" |
76 | #include "llvm/Support/ThreadPool.h" |
77 | #include "llvm/Support/ToolOutputFile.h" |
78 | #include "llvm/Support/WithColor.h" |
79 | #include "llvm/Support/raw_ostream.h" |
80 | #include "llvm/Target/TargetMachine.h" |
81 | #include "llvm/Target/TargetOptions.h" |
82 | #include "llvm/TargetParser/Triple.h" |
83 | #include <algorithm> |
84 | #include <cassert> |
85 | #include <cinttypes> |
86 | #include <climits> |
87 | #include <cstdint> |
88 | #include <cstdlib> |
89 | #include <cstring> |
90 | #include <limits> |
91 | #include <map> |
92 | #include <memory> |
93 | #include <optional> |
94 | #include <string> |
95 | #include <system_error> |
96 | #include <tuple> |
97 | #include <utility> |
98 | #include <vector> |
99 | |
100 | namespace llvm { |
101 | |
102 | static mc::RegisterMCTargetOptionsFlags MOF; |
103 | |
104 | using namespace dwarf_linker; |
105 | |
106 | namespace dsymutil { |
107 | |
108 | static void dumpDIE(const DWARFDie *DIE, bool Verbose) { |
109 | if (!DIE || !Verbose) |
110 | return; |
111 | |
112 | DIDumpOptions DumpOpts; |
113 | DumpOpts.ChildRecurseDepth = 0; |
114 | DumpOpts.Verbose = Verbose; |
115 | |
116 | WithColor::note() << " in DIE:\n" ; |
117 | DIE->dump(OS&: errs(), indent: 6 /* Indent */, DumpOpts); |
118 | } |
119 | |
120 | /// Report a warning to the user, optionally including information about a |
121 | /// specific \p DIE related to the warning. |
122 | void DwarfLinkerForBinary::reportWarning(Twine Warning, Twine Context, |
123 | const DWARFDie *DIE) const { |
124 | // FIXME: implement warning logging which does not block other threads. |
125 | if (ErrorHandlerMutex.try_lock()) { |
126 | warn(Warning, Context); |
127 | dumpDIE(DIE, Verbose: Options.Verbose); |
128 | ErrorHandlerMutex.unlock(); |
129 | } |
130 | } |
131 | |
132 | void DwarfLinkerForBinary::reportError(Twine Error, Twine Context, |
133 | const DWARFDie *DIE) const { |
134 | // FIXME: implement error logging which does not block other threads. |
135 | if (ErrorHandlerMutex.try_lock()) { |
136 | error(Error, Context); |
137 | dumpDIE(DIE, Verbose: Options.Verbose); |
138 | ErrorHandlerMutex.unlock(); |
139 | } |
140 | } |
141 | |
142 | ErrorOr<const object::ObjectFile &> |
143 | DwarfLinkerForBinary::loadObject(const DebugMapObject &Obj, |
144 | const Triple &Triple) { |
145 | auto ObjectEntry = |
146 | BinHolder.getObjectEntry(Filename: Obj.getObjectFilename(), Timestamp: Obj.getTimestamp()); |
147 | if (!ObjectEntry) { |
148 | auto Err = ObjectEntry.takeError(); |
149 | reportWarning(Warning: Twine(Obj.getObjectFilename()) + ": " + |
150 | toStringWithoutConsuming(E: Err), |
151 | Context: Obj.getObjectFilename()); |
152 | return errorToErrorCode(Err: std::move(Err)); |
153 | } |
154 | |
155 | auto Object = ObjectEntry->getObject(T: Triple); |
156 | if (!Object) { |
157 | auto Err = Object.takeError(); |
158 | reportWarning(Warning: Twine(Obj.getObjectFilename()) + ": " + |
159 | toStringWithoutConsuming(E: Err), |
160 | Context: Obj.getObjectFilename()); |
161 | return errorToErrorCode(Err: std::move(Err)); |
162 | } |
163 | |
164 | return *Object; |
165 | } |
166 | |
167 | static Error remarksErrorHandler(const DebugMapObject &DMO, |
168 | DwarfLinkerForBinary &Linker, |
169 | std::unique_ptr<FileError> FE) { |
170 | bool IsArchive = DMO.getObjectFilename().ends_with(Suffix: ")" ); |
171 | // Don't report errors for missing remark files from static |
172 | // archives. |
173 | if (!IsArchive) |
174 | return Error(std::move(FE)); |
175 | |
176 | std::string Message = FE->message(); |
177 | Error E = FE->takeError(); |
178 | Error NewE = handleErrors(E: std::move(E), Hs: [&](std::unique_ptr<ECError> EC) { |
179 | if (EC->convertToErrorCode() != std::errc::no_such_file_or_directory) |
180 | return Error(std::move(EC)); |
181 | |
182 | Linker.reportWarning(Warning: Message, Context: DMO.getObjectFilename()); |
183 | return Error(Error::success()); |
184 | }); |
185 | |
186 | if (!NewE) |
187 | return Error::success(); |
188 | |
189 | return createFileError(F: FE->getFileName(), E: std::move(NewE)); |
190 | } |
191 | Error DwarfLinkerForBinary::emitRelocations( |
192 | const DebugMap &DM, std::vector<ObjectWithRelocMap> &ObjectsForLinking) { |
193 | // Return early if the "Resources" directory is not being written to. |
194 | if (!Options.ResourceDir) |
195 | return Error::success(); |
196 | |
197 | RelocationMap RM(DM.getTriple(), DM.getBinaryPath()); |
198 | for (auto &Obj : ObjectsForLinking) { |
199 | if (!Obj.OutRelocs->isInitialized()) |
200 | continue; |
201 | Obj.OutRelocs->addValidRelocs(RM); |
202 | } |
203 | |
204 | SmallString<128> InputPath; |
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 | |
228 | static Error (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> InputPath; |
236 | SmallString<128> Path; |
237 | // Create the "Remarks" directory in the "Resources" directory. |
238 | sys::path::append(path&: Path, a: *Options.ResourceDir, b: "Remarks" ); |
239 | if (std::error_code EC = sys::fs::create_directories(path: Path.str(), IgnoreExisting: true, |
240 | Perms: sys::fs::perms::all_all)) |
241 | return errorCodeToError(EC); |
242 | |
243 | // Append the file name. |
244 | // For fat binaries, also append a dash and the architecture name. |
245 | sys::path::append(path&: Path, a: sys::path::filename(path: BinaryPath)); |
246 | if (Options.NumDebugMaps > 1) { |
247 | // More than one debug map means we have a fat binary. |
248 | Path += '-'; |
249 | Path += ArchName; |
250 | } |
251 | |
252 | std::error_code EC; |
253 | raw_fd_ostream OS(Options.NoOutput ? "-" : Path.str(), EC, |
254 | Options.RemarksFormat == remarks::Format::Bitstream |
255 | ? sys::fs::OF_None |
256 | : sys::fs::OF_Text); |
257 | if (EC) |
258 | return errorCodeToError(EC); |
259 | |
260 | if (Error E = RL.serialize(OS, RemarksFormat: Options.RemarksFormat)) |
261 | return E; |
262 | |
263 | return Error::success(); |
264 | } |
265 | |
266 | ErrorOr<std::unique_ptr<DWARFFile>> DwarfLinkerForBinary::( |
267 | const DebugMapObject &Obj, const DebugMap &DebugMap, |
268 | remarks::RemarkLinker &RL, |
269 | std::shared_ptr<DwarfLinkerForBinaryRelocationMap> DLBRM) { |
270 | auto ErrorOrObj = loadObject(Obj, Triple: DebugMap.getTriple()); |
271 | std::unique_ptr<DWARFFile> Res; |
272 | |
273 | if (ErrorOrObj) { |
274 | auto Context = DWARFContext::create( |
275 | Obj: *ErrorOrObj, RelocAction: DWARFContext::ProcessDebugRelocations::Process, L: nullptr, |
276 | DWPName: "" , |
277 | RecoverableErrorHandler: [&](Error Err) { |
278 | handleAllErrors(E: std::move(Err), Handlers: [&](ErrorInfoBase &Info) { |
279 | reportError(Error: Info.message()); |
280 | }); |
281 | }, |
282 | WarningHandler: [&](Error Warning) { |
283 | handleAllErrors(E: std::move(Warning), Handlers: [&](ErrorInfoBase &Info) { |
284 | reportWarning(Warning: Info.message()); |
285 | }); |
286 | }); |
287 | DLBRM->init(Context&: *Context); |
288 | Res = std::make_unique<DWARFFile>( |
289 | args: Obj.getObjectFilename(), args: std::move(Context), |
290 | args: std::make_unique<AddressManager>(args&: *this, args: *ErrorOrObj, args: Obj, args&: DLBRM), |
291 | args: [&](StringRef FileName) { BinHolder.eraseObjectEntry(Filename: FileName); }); |
292 | |
293 | Error E = RL.link(Obj: *ErrorOrObj); |
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 | |
306 | static 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. |
352 | static std::vector<uint64_t> |
353 | calculateStartOfStrippableReflectionSections(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 | |
400 | void 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 | |
502 | Error 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 | |
536 | void 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 | |
594 | bool 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 | |
601 | template <typename Linker> |
602 | void 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 | |
629 | template <typename Linker> |
630 | bool 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 | for (const auto &Obj : Map.objects()) { |
774 | // N_AST objects (swiftmodule files) should get dumped directly into the |
775 | // appropriate DWARF section. |
776 | if (Obj->getType() == MachO::N_AST) { |
777 | if (Options.Verbose) |
778 | outs() << "DEBUG MAP OBJECT: " << Obj->getObjectFilename() << "\n" ; |
779 | |
780 | StringRef File = Obj->getObjectFilename(); |
781 | auto ErrorOrMem = MemoryBuffer::getFile(Filename: File); |
782 | if (!ErrorOrMem) { |
783 | reportWarning(Warning: "Could not open '" + File + "'" ); |
784 | continue; |
785 | } |
786 | sys::fs::file_status Stat; |
787 | if (auto Err = sys::fs::status(path: File, result&: Stat)) { |
788 | reportWarning(Warning: Err.message()); |
789 | continue; |
790 | } |
791 | if (!Options.NoTimestamp) { |
792 | // The modification can have sub-second precision so we need to cast |
793 | // away the extra precision that's not present in the debug map. |
794 | auto ModificationTime = |
795 | std::chrono::time_point_cast<std::chrono::seconds>( |
796 | t: Stat.getLastModificationTime()); |
797 | if (Obj->getTimestamp() != sys::TimePoint<>() && |
798 | ModificationTime != Obj->getTimestamp()) { |
799 | // Not using the helper here as we can easily stream TimePoint<>. |
800 | WithColor::warning() |
801 | << File << ": timestamp mismatch between swift interface file (" |
802 | << sys::TimePoint<>(ModificationTime) << ") and debug map (" |
803 | << sys::TimePoint<>(Obj->getTimestamp()) << ")\n" ; |
804 | continue; |
805 | } |
806 | } |
807 | |
808 | // Copy the module into the .swift_ast section. |
809 | if (!Options.NoOutput) |
810 | Streamer->emitSwiftAST(Buffer: (*ErrorOrMem)->getBuffer()); |
811 | |
812 | continue; |
813 | } |
814 | |
815 | auto DLBRelocMap = std::make_shared<DwarfLinkerForBinaryRelocationMap>(); |
816 | if (ErrorOr<std::unique_ptr<DWARFFile>> ErrorOrObj = |
817 | loadObject(Obj: *Obj, DebugMap: Map, RL, DLBRM: DLBRelocMap)) { |
818 | ObjectsForLinking.emplace_back(args: std::move(*ErrorOrObj), args&: DLBRelocMap); |
819 | GeneralLinker->addObjectFile(*ObjectsForLinking.back().Object, Loader, |
820 | OnCUDieLoaded); |
821 | } else { |
822 | ObjectsForLinking.push_back( |
823 | x: {std::make_unique<DWARFFile>(args: Obj->getObjectFilename(), args: nullptr, |
824 | args: nullptr), |
825 | DLBRelocMap}); |
826 | GeneralLinker->addObjectFile(*ObjectsForLinking.back().Object); |
827 | } |
828 | } |
829 | |
830 | // If we haven't seen any CUs, pick an arbitrary valid Dwarf version anyway. |
831 | if (MaxDWARFVersion == 0) |
832 | MaxDWARFVersion = 3; |
833 | |
834 | if (Error E = GeneralLinker->setTargetDWARFVersion(MaxDWARFVersion)) |
835 | return error(Error: toString(E: std::move(E))); |
836 | |
837 | setAcceleratorTables<Linker>(*GeneralLinker, Options.TheAccelTableKind, |
838 | MaxDWARFVersion); |
839 | |
840 | // link debug info for loaded object files. |
841 | if (Error E = GeneralLinker->link()) |
842 | return error(Error: toString(E: std::move(E))); |
843 | |
844 | StringRef ArchName = Map.getTriple().getArchName(); |
845 | if (Error E = emitRemarks(Options, BinaryPath: Map.getBinaryPath(), ArchName, RL)) |
846 | return error(Error: toString(E: std::move(E))); |
847 | |
848 | if (Options.NoOutput) |
849 | return true; |
850 | |
851 | if (Error E = emitRelocations(DM: Map, ObjectsForLinking)) |
852 | return error(Error: toString(E: std::move(E))); |
853 | |
854 | if (Options.ResourceDir && !ParseableSwiftInterfaces.empty()) { |
855 | StringRef ArchName = Triple::getArchTypeName(Kind: Map.getTriple().getArch()); |
856 | if (auto E = copySwiftInterfaces(Architecture: ArchName)) |
857 | return error(Error: toString(E: std::move(E))); |
858 | } |
859 | |
860 | auto MapTriple = Map.getTriple(); |
861 | if ((MapTriple.isOSDarwin() || MapTriple.isOSBinFormatMachO()) && |
862 | !Map.getBinaryPath().empty() && |
863 | ObjectType == Linker::OutputFileType::Object) |
864 | return MachOUtils::generateDsymCompanion( |
865 | VFS: Options.VFS, DM: Map, MS&: *Streamer->getAsmPrinter().OutStreamer, OutFile, |
866 | RelocationsToApply); |
867 | |
868 | Streamer->finish(); |
869 | return true; |
870 | } |
871 | |
872 | /// Iterate over the relocations of the given \p Section and |
873 | /// store the ones that correspond to debug map entries into the |
874 | /// ValidRelocs array. |
875 | void DwarfLinkerForBinary::AddressManager::findValidRelocsMachO( |
876 | const object::SectionRef &Section, const object::MachOObjectFile &Obj, |
877 | const DebugMapObject &DMO, std::vector<ValidReloc> &ValidRelocs) { |
878 | Expected<StringRef> ContentsOrErr = Section.getContents(); |
879 | if (!ContentsOrErr) { |
880 | consumeError(Err: ContentsOrErr.takeError()); |
881 | Linker.reportWarning(Warning: "error reading section" , Context: DMO.getObjectFilename()); |
882 | return; |
883 | } |
884 | DataExtractor Data(*ContentsOrErr, Obj.isLittleEndian(), 0); |
885 | bool SkipNext = false; |
886 | |
887 | for (const object::RelocationRef &Reloc : Section.relocations()) { |
888 | if (SkipNext) { |
889 | SkipNext = false; |
890 | continue; |
891 | } |
892 | |
893 | object::DataRefImpl RelocDataRef = Reloc.getRawDataRefImpl(); |
894 | MachO::any_relocation_info MachOReloc = Obj.getRelocation(Rel: RelocDataRef); |
895 | |
896 | if (object::MachOObjectFile::isMachOPairedReloc(RelocType: Obj.getAnyRelocationType(RE: MachOReloc), |
897 | Arch: Obj.getArch())) { |
898 | SkipNext = true; |
899 | Linker.reportWarning(Warning: "unsupported relocation in " + *Section.getName() + |
900 | " section." , |
901 | Context: DMO.getObjectFilename()); |
902 | continue; |
903 | } |
904 | |
905 | unsigned RelocSize = 1 << Obj.getAnyRelocationLength(RE: MachOReloc); |
906 | uint64_t Offset64 = Reloc.getOffset(); |
907 | if ((RelocSize != 4 && RelocSize != 8)) { |
908 | Linker.reportWarning(Warning: "unsupported relocation in " + *Section.getName() + |
909 | " section." , |
910 | Context: DMO.getObjectFilename()); |
911 | continue; |
912 | } |
913 | uint64_t OffsetCopy = Offset64; |
914 | // Mach-o uses REL relocations, the addend is at the relocation offset. |
915 | uint64_t Addend = Data.getUnsigned(offset_ptr: &OffsetCopy, byte_size: RelocSize); |
916 | uint64_t SymAddress; |
917 | int64_t SymOffset; |
918 | |
919 | if (Obj.isRelocationScattered(RE: MachOReloc)) { |
920 | // The address of the base symbol for scattered relocations is |
921 | // stored in the reloc itself. The actual addend will store the |
922 | // base address plus the offset. |
923 | SymAddress = Obj.getScatteredRelocationValue(RE: MachOReloc); |
924 | SymOffset = int64_t(Addend) - SymAddress; |
925 | } else { |
926 | SymAddress = Addend; |
927 | SymOffset = 0; |
928 | } |
929 | |
930 | auto Sym = Reloc.getSymbol(); |
931 | if (Sym != Obj.symbol_end()) { |
932 | Expected<StringRef> SymbolName = Sym->getName(); |
933 | if (!SymbolName) { |
934 | consumeError(Err: SymbolName.takeError()); |
935 | Linker.reportWarning(Warning: "error getting relocation symbol name." , |
936 | Context: DMO.getObjectFilename()); |
937 | continue; |
938 | } |
939 | if (const auto *Mapping = DMO.lookupSymbol(SymbolName: *SymbolName)) |
940 | ValidRelocs.emplace_back(args&: Offset64, args&: RelocSize, args&: Addend, args: Mapping->getKey(), |
941 | args: Mapping->getValue()); |
942 | } else if (const auto *Mapping = DMO.lookupObjectAddress(Address: SymAddress)) { |
943 | // Do not store the addend. The addend was the address of the symbol in |
944 | // the object file, the address in the binary that is stored in the debug |
945 | // map doesn't need to be offset. |
946 | ValidRelocs.emplace_back(args&: Offset64, args&: RelocSize, args&: SymOffset, |
947 | args: Mapping->getKey(), args: Mapping->getValue()); |
948 | } |
949 | } |
950 | } |
951 | |
952 | /// Dispatch the valid relocation finding logic to the |
953 | /// appropriate handler depending on the object file format. |
954 | bool DwarfLinkerForBinary::AddressManager::findValidRelocs( |
955 | const object::SectionRef &Section, const object::ObjectFile &Obj, |
956 | const DebugMapObject &DMO, std::vector<ValidReloc> &Relocs) { |
957 | // Dispatch to the right handler depending on the file type. |
958 | if (auto *MachOObj = dyn_cast<object::MachOObjectFile>(Val: &Obj)) |
959 | findValidRelocsMachO(Section, Obj: *MachOObj, DMO, ValidRelocs&: Relocs); |
960 | else |
961 | Linker.reportWarning(Warning: Twine("unsupported object file type: " ) + |
962 | Obj.getFileName(), |
963 | Context: DMO.getObjectFilename()); |
964 | if (Relocs.empty()) |
965 | return false; |
966 | |
967 | // Sort the relocations by offset. We will walk the DIEs linearly in |
968 | // the file, this allows us to just keep an index in the relocation |
969 | // array that we advance during our walk, rather than resorting to |
970 | // some associative container. See DwarfLinkerForBinary::NextValidReloc. |
971 | llvm::sort(C&: Relocs); |
972 | return true; |
973 | } |
974 | |
975 | /// Look for relocations in the debug_info and debug_addr section that match |
976 | /// entries in the debug map. These relocations will drive the Dwarf link by |
977 | /// indicating which DIEs refer to symbols present in the linked binary. |
978 | /// \returns whether there are any valid relocations in the debug info. |
979 | bool DwarfLinkerForBinary::AddressManager::findValidRelocsInDebugSections( |
980 | const object::ObjectFile &Obj, const DebugMapObject &DMO) { |
981 | // Find the debug_info section. |
982 | bool FoundValidRelocs = false; |
983 | for (const object::SectionRef &Section : Obj.sections()) { |
984 | StringRef SectionName; |
985 | if (Expected<StringRef> NameOrErr = Section.getName()) |
986 | SectionName = *NameOrErr; |
987 | else |
988 | consumeError(Err: NameOrErr.takeError()); |
989 | |
990 | SectionName = SectionName.substr(Start: SectionName.find_first_not_of(Chars: "._" )); |
991 | if (SectionName == "debug_info" ) |
992 | FoundValidRelocs |= |
993 | findValidRelocs(Section, Obj, DMO, Relocs&: ValidDebugInfoRelocs); |
994 | if (SectionName == "debug_addr" ) |
995 | FoundValidRelocs |= |
996 | findValidRelocs(Section, Obj, DMO, Relocs&: ValidDebugAddrRelocs); |
997 | } |
998 | return FoundValidRelocs; |
999 | } |
1000 | |
1001 | std::vector<ValidReloc> DwarfLinkerForBinary::AddressManager::getRelocations( |
1002 | const std::vector<ValidReloc> &Relocs, uint64_t StartPos, uint64_t EndPos) { |
1003 | std::vector<ValidReloc> Res; |
1004 | |
1005 | auto CurReloc = partition_point(Range: Relocs, P: [StartPos](const ValidReloc &Reloc) { |
1006 | return (uint64_t)Reloc.Offset < StartPos; |
1007 | }); |
1008 | |
1009 | while (CurReloc != Relocs.end() && CurReloc->Offset >= StartPos && |
1010 | (uint64_t)CurReloc->Offset < EndPos) { |
1011 | Res.push_back(x: *CurReloc); |
1012 | CurReloc++; |
1013 | } |
1014 | |
1015 | return Res; |
1016 | } |
1017 | |
1018 | void DwarfLinkerForBinary::AddressManager::printReloc(const ValidReloc &Reloc) { |
1019 | const auto &Mapping = Reloc.SymbolMapping; |
1020 | const uint64_t ObjectAddress = Mapping.ObjectAddress |
1021 | ? uint64_t(*Mapping.ObjectAddress) |
1022 | : std::numeric_limits<uint64_t>::max(); |
1023 | |
1024 | outs() << "Found valid debug map entry: " << Reloc.SymbolName << "\t" |
1025 | << format(Fmt: "0x%016" PRIx64 " => 0x%016" PRIx64 "\n" , Vals: ObjectAddress, |
1026 | Vals: uint64_t(Mapping.BinaryAddress)); |
1027 | } |
1028 | |
1029 | int64_t |
1030 | DwarfLinkerForBinary::AddressManager::getRelocValue(const ValidReloc &Reloc) { |
1031 | int64_t AddrAdjust = relocate(Reloc); |
1032 | if (Reloc.SymbolMapping.ObjectAddress) |
1033 | AddrAdjust -= uint64_t(*Reloc.SymbolMapping.ObjectAddress); |
1034 | return AddrAdjust; |
1035 | } |
1036 | |
1037 | std::optional<int64_t> |
1038 | DwarfLinkerForBinary::AddressManager::hasValidRelocationAt( |
1039 | const std::vector<ValidReloc> &AllRelocs, uint64_t StartOffset, |
1040 | uint64_t EndOffset, bool Verbose) { |
1041 | std::vector<ValidReloc> Relocs = |
1042 | getRelocations(Relocs: AllRelocs, StartPos: StartOffset, EndPos: EndOffset); |
1043 | if (Relocs.size() == 0) |
1044 | return std::nullopt; |
1045 | |
1046 | if (Verbose) |
1047 | printReloc(Reloc: Relocs[0]); |
1048 | |
1049 | return getRelocValue(Reloc: Relocs[0]); |
1050 | } |
1051 | |
1052 | /// Get the starting and ending (exclusive) offset for the |
1053 | /// attribute with index \p Idx descibed by \p Abbrev. \p Offset is |
1054 | /// supposed to point to the position of the first attribute described |
1055 | /// by \p Abbrev. |
1056 | /// \return [StartOffset, EndOffset) as a pair. |
1057 | static std::pair<uint64_t, uint64_t> |
1058 | getAttributeOffsets(const DWARFAbbreviationDeclaration *Abbrev, unsigned Idx, |
1059 | uint64_t Offset, const DWARFUnit &Unit) { |
1060 | DataExtractor Data = Unit.getDebugInfoExtractor(); |
1061 | |
1062 | for (unsigned I = 0; I < Idx; ++I) |
1063 | DWARFFormValue::skipValue(Form: Abbrev->getFormByIndex(idx: I), DebugInfoData: Data, OffsetPtr: &Offset, |
1064 | FormParams: Unit.getFormParams()); |
1065 | |
1066 | uint64_t End = Offset; |
1067 | DWARFFormValue::skipValue(Form: Abbrev->getFormByIndex(idx: Idx), DebugInfoData: Data, OffsetPtr: &End, |
1068 | FormParams: Unit.getFormParams()); |
1069 | |
1070 | return std::make_pair(x&: Offset, y&: End); |
1071 | } |
1072 | |
1073 | std::optional<int64_t> |
1074 | DwarfLinkerForBinary::AddressManager::getExprOpAddressRelocAdjustment( |
1075 | DWARFUnit &U, const DWARFExpression::Operation &Op, uint64_t StartOffset, |
1076 | uint64_t EndOffset, bool Verbose) { |
1077 | switch (Op.getCode()) { |
1078 | default: { |
1079 | assert(false && "Specified operation does not have address operand" ); |
1080 | } break; |
1081 | case dwarf::DW_OP_const2u: |
1082 | case dwarf::DW_OP_const4u: |
1083 | case dwarf::DW_OP_const8u: |
1084 | case dwarf::DW_OP_const2s: |
1085 | case dwarf::DW_OP_const4s: |
1086 | case dwarf::DW_OP_const8s: |
1087 | case dwarf::DW_OP_addr: { |
1088 | return hasValidRelocationAt(AllRelocs: ValidDebugInfoRelocs, StartOffset, EndOffset, |
1089 | Verbose); |
1090 | } break; |
1091 | case dwarf::DW_OP_constx: |
1092 | case dwarf::DW_OP_addrx: { |
1093 | return hasValidRelocationAt(AllRelocs: ValidDebugAddrRelocs, StartOffset, EndOffset, |
1094 | Verbose); |
1095 | } break; |
1096 | } |
1097 | |
1098 | return std::nullopt; |
1099 | } |
1100 | |
1101 | std::optional<int64_t> |
1102 | DwarfLinkerForBinary::AddressManager::getSubprogramRelocAdjustment( |
1103 | const DWARFDie &DIE, bool Verbose) { |
1104 | const auto *Abbrev = DIE.getAbbreviationDeclarationPtr(); |
1105 | |
1106 | std::optional<uint32_t> LowPcIdx = |
1107 | Abbrev->findAttributeIndex(attr: dwarf::DW_AT_low_pc); |
1108 | if (!LowPcIdx) |
1109 | return std::nullopt; |
1110 | |
1111 | dwarf::Form Form = Abbrev->getFormByIndex(idx: *LowPcIdx); |
1112 | |
1113 | switch (Form) { |
1114 | case dwarf::DW_FORM_addr: { |
1115 | uint64_t Offset = DIE.getOffset() + getULEB128Size(Value: Abbrev->getCode()); |
1116 | uint64_t LowPcOffset, LowPcEndOffset; |
1117 | std::tie(args&: LowPcOffset, args&: LowPcEndOffset) = |
1118 | getAttributeOffsets(Abbrev, Idx: *LowPcIdx, Offset, Unit: *DIE.getDwarfUnit()); |
1119 | return hasValidRelocationAt(AllRelocs: ValidDebugInfoRelocs, StartOffset: LowPcOffset, |
1120 | EndOffset: LowPcEndOffset, Verbose); |
1121 | } |
1122 | case dwarf::DW_FORM_addrx: |
1123 | case dwarf::DW_FORM_addrx1: |
1124 | case dwarf::DW_FORM_addrx2: |
1125 | case dwarf::DW_FORM_addrx3: |
1126 | case dwarf::DW_FORM_addrx4: { |
1127 | std::optional<DWARFFormValue> AddrValue = DIE.find(Attr: dwarf::DW_AT_low_pc); |
1128 | if (std::optional<uint64_t> AddressOffset = |
1129 | DIE.getDwarfUnit()->getIndexedAddressOffset( |
1130 | Index: AddrValue->getRawUValue())) |
1131 | return hasValidRelocationAt( |
1132 | AllRelocs: ValidDebugAddrRelocs, StartOffset: *AddressOffset, |
1133 | EndOffset: *AddressOffset + DIE.getDwarfUnit()->getAddressByteSize(), Verbose); |
1134 | |
1135 | Linker.reportWarning(Warning: "no base offset for address table" , Context: SrcFileName); |
1136 | return std::nullopt; |
1137 | } |
1138 | default: |
1139 | return std::nullopt; |
1140 | } |
1141 | } |
1142 | |
1143 | std::optional<StringRef> |
1144 | DwarfLinkerForBinary::AddressManager::getLibraryInstallName() { |
1145 | return LibInstallName; |
1146 | } |
1147 | |
1148 | uint64_t |
1149 | DwarfLinkerForBinary::AddressManager::relocate(const ValidReloc &Reloc) const { |
1150 | return Reloc.SymbolMapping.BinaryAddress + Reloc.Addend; |
1151 | } |
1152 | |
1153 | void DwarfLinkerForBinary::AddressManager::updateAndSaveValidRelocs( |
1154 | bool IsDWARF5, uint64_t OriginalUnitOffset, int64_t LinkedOffset, |
1155 | uint64_t StartOffset, uint64_t EndOffset) { |
1156 | std::vector<ValidReloc> InRelocs = |
1157 | getRelocations(Relocs: ValidDebugInfoRelocs, StartPos: StartOffset, EndPos: EndOffset); |
1158 | if (IsDWARF5) |
1159 | InRelocs = getRelocations(Relocs: ValidDebugAddrRelocs, StartPos: StartOffset, EndPos: EndOffset); |
1160 | DwarfLinkerRelocMap->updateAndSaveValidRelocs( |
1161 | IsDWARF5, InRelocs, UnitOffset: OriginalUnitOffset, LinkedOffset); |
1162 | } |
1163 | |
1164 | void DwarfLinkerForBinary::AddressManager::updateRelocationsWithUnitOffset( |
1165 | uint64_t OriginalUnitOffset, uint64_t OutputUnitOffset) { |
1166 | DwarfLinkerRelocMap->updateRelocationsWithUnitOffset(OriginalUnitOffset, |
1167 | OutputUnitOffset); |
1168 | } |
1169 | /// Apply the valid relocations found by findValidRelocs() to |
1170 | /// the buffer \p Data, taking into account that Data is at \p BaseOffset |
1171 | /// in the debug_info section. |
1172 | /// |
1173 | /// Like for findValidRelocs(), this function must be called with |
1174 | /// monotonic \p BaseOffset values. |
1175 | /// |
1176 | /// \returns whether any reloc has been applied. |
1177 | bool DwarfLinkerForBinary::AddressManager::applyValidRelocs( |
1178 | MutableArrayRef<char> Data, uint64_t BaseOffset, bool IsLittleEndian) { |
1179 | |
1180 | std::vector<ValidReloc> Relocs = getRelocations( |
1181 | Relocs: ValidDebugInfoRelocs, StartPos: BaseOffset, EndPos: BaseOffset + Data.size()); |
1182 | |
1183 | for (const ValidReloc &CurReloc : Relocs) { |
1184 | assert(CurReloc.Offset - BaseOffset < Data.size()); |
1185 | assert(CurReloc.Offset - BaseOffset + CurReloc.Size <= Data.size()); |
1186 | char Buf[8]; |
1187 | uint64_t Value = relocate(Reloc: CurReloc); |
1188 | for (unsigned I = 0; I != CurReloc.Size; ++I) { |
1189 | unsigned Index = IsLittleEndian ? I : (CurReloc.Size - I - 1); |
1190 | Buf[I] = uint8_t(Value >> (Index * 8)); |
1191 | } |
1192 | assert(CurReloc.Size <= sizeof(Buf)); |
1193 | memcpy(dest: &Data[CurReloc.Offset - BaseOffset], src: Buf, n: CurReloc.Size); |
1194 | } |
1195 | return Relocs.size() > 0; |
1196 | } |
1197 | |
1198 | void DwarfLinkerForBinaryRelocationMap::init(DWARFContext &Context) { |
1199 | for (const std::unique_ptr<DWARFUnit> &CU : Context.compile_units()) |
1200 | StoredValidDebugInfoRelocsMap.insert( |
1201 | KV: std::make_pair(x: CU->getOffset(), y: std::vector<ValidReloc>())); |
1202 | // FIXME: Support relocations debug_addr (DWARF5). |
1203 | } |
1204 | |
1205 | void DwarfLinkerForBinaryRelocationMap::addValidRelocs(RelocationMap &RM) { |
1206 | for (const auto &DebugInfoRelocs : StoredValidDebugInfoRelocsMap) { |
1207 | for (const auto &InfoReloc : DebugInfoRelocs.second) |
1208 | RM.addRelocationMapEntry(Relocation: InfoReloc); |
1209 | } |
1210 | // FIXME: Support relocations debug_addr (DWARF5). |
1211 | } |
1212 | |
1213 | void DwarfLinkerForBinaryRelocationMap::updateRelocationsWithUnitOffset( |
1214 | uint64_t OriginalUnitOffset, uint64_t OutputUnitOffset) { |
1215 | std::vector<ValidReloc> &StoredValidDebugInfoRelocs = |
1216 | StoredValidDebugInfoRelocsMap[OriginalUnitOffset]; |
1217 | for (ValidReloc &R : StoredValidDebugInfoRelocs) { |
1218 | R.Offset = (uint64_t)R.Offset + OutputUnitOffset; |
1219 | } |
1220 | // FIXME: Support relocations debug_addr (DWARF5). |
1221 | } |
1222 | |
1223 | void DwarfLinkerForBinaryRelocationMap::updateAndSaveValidRelocs( |
1224 | bool IsDWARF5, std::vector<ValidReloc> &InRelocs, uint64_t UnitOffset, |
1225 | int64_t LinkedOffset) { |
1226 | std::vector<ValidReloc> &OutRelocs = |
1227 | StoredValidDebugInfoRelocsMap[UnitOffset]; |
1228 | if (IsDWARF5) |
1229 | OutRelocs = StoredValidDebugAddrRelocsMap[UnitOffset]; |
1230 | |
1231 | for (ValidReloc &R : InRelocs) { |
1232 | OutRelocs.emplace_back(args: R.Offset + LinkedOffset, args&: R.Size, args&: R.Addend, |
1233 | args&: R.SymbolName, args&: R.SymbolMapping); |
1234 | } |
1235 | } |
1236 | |
1237 | } // namespace dsymutil |
1238 | } // namespace llvm |
1239 | |