1 //===-- DWARFContext.cpp --------------------------------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
11 #include "llvm/ADT/SmallString.h"
12 #include "llvm/ADT/StringSwitch.h"
13 #include "llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h"
14 #include "llvm/DebugInfo/DWARF/DWARFDebugArangeSet.h"
15 #include "llvm/DebugInfo/DWARF/DWARFUnitIndex.h"
16 #include "llvm/Support/Compression.h"
17 #include "llvm/Support/Dwarf.h"
18 #include "llvm/Support/Format.h"
19 #include "llvm/Support/Path.h"
20 #include "llvm/Support/raw_ostream.h"
23 using namespace dwarf;
24 using namespace object;
26 #define DEBUG_TYPE "dwarf"
28 typedef DWARFDebugLine::LineTable DWARFLineTable;
29 typedef DILineInfoSpecifier::FileLineInfoKind FileLineInfoKind;
30 typedef DILineInfoSpecifier::FunctionNameKind FunctionNameKind;
32 static void dumpPubSection(raw_ostream &OS, StringRef Name, StringRef Data,
33 bool LittleEndian, bool GnuStyle) {
34 OS << "\n." << Name << " contents:\n";
35 DataExtractor pubNames(Data, LittleEndian, 0);
37 while (pubNames.isValidOffset(offset)) {
38 OS << "length = " << format("0x%08x", pubNames.getU32(&offset));
39 OS << " version = " << format("0x%04x", pubNames.getU16(&offset));
40 OS << " unit_offset = " << format("0x%08x", pubNames.getU32(&offset));
41 OS << " unit_size = " << format("0x%08x", pubNames.getU32(&offset)) << '\n';
43 OS << "Offset Linkage Kind Name\n";
45 OS << "Offset Name\n";
47 while (offset < Data.size()) {
48 uint32_t dieRef = pubNames.getU32(&offset);
51 OS << format("0x%8.8x ", dieRef);
53 PubIndexEntryDescriptor desc(pubNames.getU8(&offset));
54 OS << format("%-8s", dwarf::GDBIndexEntryLinkageString(desc.Linkage))
55 << ' ' << format("%-8s", dwarf::GDBIndexEntryKindString(desc.Kind))
58 OS << '\"' << pubNames.getCStr(&offset) << "\"\n";
63 static void dumpAccelSection(raw_ostream &OS, StringRef Name,
64 const DWARFSection& Section, StringRef StringSection,
66 DataExtractor AccelSection(Section.Data, LittleEndian, 0);
67 DataExtractor StrData(StringSection, LittleEndian, 0);
68 OS << "\n." << Name << " contents:\n";
69 DWARFAcceleratorTable Accel(AccelSection, StrData, Section.Relocs);
75 void DWARFContext::dump(raw_ostream &OS, DIDumpType DumpType) {
76 if (DumpType == DIDT_All || DumpType == DIDT_Abbrev) {
77 OS << ".debug_abbrev contents:\n";
78 getDebugAbbrev()->dump(OS);
81 if (DumpType == DIDT_All || DumpType == DIDT_AbbrevDwo)
82 if (const DWARFDebugAbbrev *D = getDebugAbbrevDWO()) {
83 OS << "\n.debug_abbrev.dwo contents:\n";
87 if (DumpType == DIDT_All || DumpType == DIDT_Info) {
88 OS << "\n.debug_info contents:\n";
89 for (const auto &CU : compile_units())
93 if ((DumpType == DIDT_All || DumpType == DIDT_InfoDwo) &&
94 getNumDWOCompileUnits()) {
95 OS << "\n.debug_info.dwo contents:\n";
96 for (const auto &DWOCU : dwo_compile_units())
100 if ((DumpType == DIDT_All || DumpType == DIDT_Types) && getNumTypeUnits()) {
101 OS << "\n.debug_types contents:\n";
102 for (const auto &TUS : type_unit_sections())
103 for (const auto &TU : TUS)
107 if ((DumpType == DIDT_All || DumpType == DIDT_TypesDwo) &&
108 getNumDWOTypeUnits()) {
109 OS << "\n.debug_types.dwo contents:\n";
110 for (const auto &DWOTUS : dwo_type_unit_sections())
111 for (const auto &DWOTU : DWOTUS)
115 if (DumpType == DIDT_All || DumpType == DIDT_Loc) {
116 OS << "\n.debug_loc contents:\n";
117 getDebugLoc()->dump(OS);
120 if (DumpType == DIDT_All || DumpType == DIDT_LocDwo) {
121 OS << "\n.debug_loc.dwo contents:\n";
122 getDebugLocDWO()->dump(OS);
125 if (DumpType == DIDT_All || DumpType == DIDT_Frames) {
126 OS << "\n.debug_frame contents:\n";
127 getDebugFrame()->dump(OS);
130 if (DumpType == DIDT_All || DumpType == DIDT_Macro) {
131 OS << "\n.debug_macinfo contents:\n";
132 getDebugMacro()->dump(OS);
136 if (DumpType == DIDT_All || DumpType == DIDT_Aranges) {
137 OS << "\n.debug_aranges contents:\n";
138 DataExtractor arangesData(getARangeSection(), isLittleEndian(), 0);
139 DWARFDebugArangeSet set;
140 while (set.extract(arangesData, &offset))
144 uint8_t savedAddressByteSize = 0;
145 if (DumpType == DIDT_All || DumpType == DIDT_Line) {
146 OS << "\n.debug_line contents:\n";
147 for (const auto &CU : compile_units()) {
148 savedAddressByteSize = CU->getAddressByteSize();
149 const auto *CUDIE = CU->getUnitDIE();
150 if (CUDIE == nullptr)
152 unsigned stmtOffset = CUDIE->getAttributeValueAsSectionOffset(
153 CU.get(), DW_AT_stmt_list, -1U);
154 if (stmtOffset != -1U) {
155 DataExtractor lineData(getLineSection().Data, isLittleEndian(),
156 savedAddressByteSize);
157 DWARFDebugLine::LineTable LineTable;
158 LineTable.parse(lineData, &getLineSection().Relocs, &stmtOffset);
164 if (DumpType == DIDT_All || DumpType == DIDT_CUIndex) {
165 OS << "\n.debug_cu_index contents:\n";
166 DataExtractor CUIndexData(getCUIndexSection(), isLittleEndian(),
167 savedAddressByteSize);
168 DWARFUnitIndex CUIndex;
169 if (CUIndex.parse(CUIndexData))
173 if (DumpType == DIDT_All || DumpType == DIDT_TUIndex) {
174 OS << "\n.debug_tu_index contents:\n";
175 DataExtractor TUIndexData(getTUIndexSection(), isLittleEndian(),
176 savedAddressByteSize);
177 DWARFUnitIndex TUIndex;
178 if (TUIndex.parse(TUIndexData))
182 if (DumpType == DIDT_All || DumpType == DIDT_LineDwo) {
183 OS << "\n.debug_line.dwo contents:\n";
184 unsigned stmtOffset = 0;
185 DataExtractor lineData(getLineDWOSection().Data, isLittleEndian(),
186 savedAddressByteSize);
187 DWARFDebugLine::LineTable LineTable;
188 while (LineTable.Prologue.parse(lineData, &stmtOffset)) {
194 if (DumpType == DIDT_All || DumpType == DIDT_Str) {
195 OS << "\n.debug_str contents:\n";
196 DataExtractor strData(getStringSection(), isLittleEndian(), 0);
198 uint32_t strOffset = 0;
199 while (const char *s = strData.getCStr(&offset)) {
200 OS << format("0x%8.8x: \"%s\"\n", strOffset, s);
205 if ((DumpType == DIDT_All || DumpType == DIDT_StrDwo) &&
206 !getStringDWOSection().empty()) {
207 OS << "\n.debug_str.dwo contents:\n";
208 DataExtractor strDWOData(getStringDWOSection(), isLittleEndian(), 0);
210 uint32_t strDWOOffset = 0;
211 while (const char *s = strDWOData.getCStr(&offset)) {
212 OS << format("0x%8.8x: \"%s\"\n", strDWOOffset, s);
213 strDWOOffset = offset;
217 if (DumpType == DIDT_All || DumpType == DIDT_Ranges) {
218 OS << "\n.debug_ranges contents:\n";
219 // In fact, different compile units may have different address byte
220 // sizes, but for simplicity we just use the address byte size of the last
221 // compile unit (there is no easy and fast way to associate address range
222 // list and the compile unit it describes).
223 DataExtractor rangesData(getRangeSection(), isLittleEndian(),
224 savedAddressByteSize);
226 DWARFDebugRangeList rangeList;
227 while (rangeList.extract(rangesData, &offset))
231 if (DumpType == DIDT_All || DumpType == DIDT_Pubnames)
232 dumpPubSection(OS, "debug_pubnames", getPubNamesSection(),
233 isLittleEndian(), false);
235 if (DumpType == DIDT_All || DumpType == DIDT_Pubtypes)
236 dumpPubSection(OS, "debug_pubtypes", getPubTypesSection(),
237 isLittleEndian(), false);
239 if (DumpType == DIDT_All || DumpType == DIDT_GnuPubnames)
240 dumpPubSection(OS, "debug_gnu_pubnames", getGnuPubNamesSection(),
241 isLittleEndian(), true /* GnuStyle */);
243 if (DumpType == DIDT_All || DumpType == DIDT_GnuPubtypes)
244 dumpPubSection(OS, "debug_gnu_pubtypes", getGnuPubTypesSection(),
245 isLittleEndian(), true /* GnuStyle */);
247 if ((DumpType == DIDT_All || DumpType == DIDT_StrOffsetsDwo) &&
248 !getStringOffsetDWOSection().empty()) {
249 OS << "\n.debug_str_offsets.dwo contents:\n";
250 DataExtractor strOffsetExt(getStringOffsetDWOSection(), isLittleEndian(),
253 uint64_t size = getStringOffsetDWOSection().size();
254 while (offset < size) {
255 OS << format("0x%8.8x: ", offset);
256 OS << format("%8.8x\n", strOffsetExt.getU32(&offset));
260 if (DumpType == DIDT_All || DumpType == DIDT_AppleNames)
261 dumpAccelSection(OS, "apple_names", getAppleNamesSection(),
262 getStringSection(), isLittleEndian());
264 if (DumpType == DIDT_All || DumpType == DIDT_AppleTypes)
265 dumpAccelSection(OS, "apple_types", getAppleTypesSection(),
266 getStringSection(), isLittleEndian());
268 if (DumpType == DIDT_All || DumpType == DIDT_AppleNamespaces)
269 dumpAccelSection(OS, "apple_namespaces", getAppleNamespacesSection(),
270 getStringSection(), isLittleEndian());
272 if (DumpType == DIDT_All || DumpType == DIDT_AppleObjC)
273 dumpAccelSection(OS, "apple_objc", getAppleObjCSection(),
274 getStringSection(), isLittleEndian());
277 const DWARFUnitIndex &DWARFContext::getCUIndex() {
281 DataExtractor CUIndexData(getCUIndexSection(), isLittleEndian(), 0);
283 CUIndex = llvm::make_unique<DWARFUnitIndex>();
284 CUIndex->parse(CUIndexData);
288 const DWARFUnitIndex &DWARFContext::getTUIndex() {
292 DataExtractor TUIndexData(getTUIndexSection(), isLittleEndian(), 0);
294 TUIndex = llvm::make_unique<DWARFUnitIndex>();
295 TUIndex->parse(TUIndexData);
299 const DWARFDebugAbbrev *DWARFContext::getDebugAbbrev() {
303 DataExtractor abbrData(getAbbrevSection(), isLittleEndian(), 0);
305 Abbrev.reset(new DWARFDebugAbbrev());
306 Abbrev->extract(abbrData);
310 const DWARFDebugAbbrev *DWARFContext::getDebugAbbrevDWO() {
312 return AbbrevDWO.get();
314 DataExtractor abbrData(getAbbrevDWOSection(), isLittleEndian(), 0);
315 AbbrevDWO.reset(new DWARFDebugAbbrev());
316 AbbrevDWO->extract(abbrData);
317 return AbbrevDWO.get();
320 const DWARFDebugLoc *DWARFContext::getDebugLoc() {
324 DataExtractor LocData(getLocSection().Data, isLittleEndian(), 0);
325 Loc.reset(new DWARFDebugLoc(getLocSection().Relocs));
326 // assume all compile units have the same address byte size
327 if (getNumCompileUnits())
328 Loc->parse(LocData, getCompileUnitAtIndex(0)->getAddressByteSize());
332 const DWARFDebugLocDWO *DWARFContext::getDebugLocDWO() {
336 DataExtractor LocData(getLocDWOSection().Data, isLittleEndian(), 0);
337 LocDWO.reset(new DWARFDebugLocDWO());
338 LocDWO->parse(LocData);
342 const DWARFDebugAranges *DWARFContext::getDebugAranges() {
344 return Aranges.get();
346 Aranges.reset(new DWARFDebugAranges());
347 Aranges->generate(this);
348 return Aranges.get();
351 const DWARFDebugFrame *DWARFContext::getDebugFrame() {
353 return DebugFrame.get();
355 // There's a "bug" in the DWARFv3 standard with respect to the target address
356 // size within debug frame sections. While DWARF is supposed to be independent
357 // of its container, FDEs have fields with size being "target address size",
358 // which isn't specified in DWARF in general. It's only specified for CUs, but
359 // .eh_frame can appear without a .debug_info section. Follow the example of
360 // other tools (libdwarf) and extract this from the container (ObjectFile
361 // provides this information). This problem is fixed in DWARFv4
362 // See this dwarf-discuss discussion for more details:
363 // http://lists.dwarfstd.org/htdig.cgi/dwarf-discuss-dwarfstd.org/2011-December/001173.html
364 DataExtractor debugFrameData(getDebugFrameSection(), isLittleEndian(),
366 DebugFrame.reset(new DWARFDebugFrame());
367 DebugFrame->parse(debugFrameData);
368 return DebugFrame.get();
371 const DWARFDebugMacro *DWARFContext::getDebugMacro() {
375 DataExtractor MacinfoData(getMacinfoSection(), isLittleEndian(), 0);
376 Macro.reset(new DWARFDebugMacro());
377 Macro->parse(MacinfoData);
381 const DWARFLineTable *
382 DWARFContext::getLineTableForUnit(DWARFUnit *U) {
384 Line.reset(new DWARFDebugLine(&getLineSection().Relocs));
385 const auto *UnitDIE = U->getUnitDIE();
386 if (UnitDIE == nullptr)
388 unsigned stmtOffset =
389 UnitDIE->getAttributeValueAsSectionOffset(U, DW_AT_stmt_list, -1U);
390 if (stmtOffset == -1U)
391 return nullptr; // No line table for this compile unit.
393 // See if the line table is cached.
394 if (const DWARFLineTable *lt = Line->getLineTable(stmtOffset))
397 // We have to parse it first.
398 DataExtractor lineData(getLineSection().Data, isLittleEndian(),
399 U->getAddressByteSize());
400 return Line->getOrParseLineTable(lineData, stmtOffset);
403 void DWARFContext::parseCompileUnits() {
404 CUs.parse(*this, getInfoSection());
407 void DWARFContext::parseTypeUnits() {
410 for (const auto &I : getTypesSections()) {
412 TUs.back().parse(*this, I.second);
416 void DWARFContext::parseDWOCompileUnits() {
417 DWOCUs.parseDWO(*this, getInfoDWOSection());
420 void DWARFContext::parseDWOTypeUnits() {
423 for (const auto &I : getTypesDWOSections()) {
424 DWOTUs.emplace_back();
425 DWOTUs.back().parseDWO(*this, I.second);
429 DWARFCompileUnit *DWARFContext::getCompileUnitForOffset(uint32_t Offset) {
431 return CUs.getUnitForOffset(Offset);
434 DWARFCompileUnit *DWARFContext::getCompileUnitForAddress(uint64_t Address) {
435 // First, get the offset of the compile unit.
436 uint32_t CUOffset = getDebugAranges()->findAddress(Address);
437 // Retrieve the compile unit.
438 return getCompileUnitForOffset(CUOffset);
441 static bool getFunctionNameForAddress(DWARFCompileUnit *CU, uint64_t Address,
442 FunctionNameKind Kind,
443 std::string &FunctionName) {
444 if (Kind == FunctionNameKind::None)
446 // The address may correspond to instruction in some inlined function,
447 // so we have to build the chain of inlined functions and take the
448 // name of the topmost function in it.
449 const DWARFDebugInfoEntryInlinedChain &InlinedChain =
450 CU->getInlinedChainForAddress(Address);
451 if (InlinedChain.DIEs.size() == 0)
453 const DWARFDebugInfoEntryMinimal &TopFunctionDIE = InlinedChain.DIEs[0];
454 if (const char *Name =
455 TopFunctionDIE.getSubroutineName(InlinedChain.U, Kind)) {
462 DILineInfo DWARFContext::getLineInfoForAddress(uint64_t Address,
463 DILineInfoSpecifier Spec) {
466 DWARFCompileUnit *CU = getCompileUnitForAddress(Address);
469 getFunctionNameForAddress(CU, Address, Spec.FNKind, Result.FunctionName);
470 if (Spec.FLIKind != FileLineInfoKind::None) {
471 if (const DWARFLineTable *LineTable = getLineTableForUnit(CU))
472 LineTable->getFileLineInfoForAddress(Address, CU->getCompilationDir(),
473 Spec.FLIKind, Result);
479 DWARFContext::getLineInfoForAddressRange(uint64_t Address, uint64_t Size,
480 DILineInfoSpecifier Spec) {
481 DILineInfoTable Lines;
482 DWARFCompileUnit *CU = getCompileUnitForAddress(Address);
486 std::string FunctionName = "<invalid>";
487 getFunctionNameForAddress(CU, Address, Spec.FNKind, FunctionName);
489 // If the Specifier says we don't need FileLineInfo, just
490 // return the top-most function at the starting address.
491 if (Spec.FLIKind == FileLineInfoKind::None) {
493 Result.FunctionName = FunctionName;
494 Lines.push_back(std::make_pair(Address, Result));
498 const DWARFLineTable *LineTable = getLineTableForUnit(CU);
500 // Get the index of row we're looking for in the line table.
501 std::vector<uint32_t> RowVector;
502 if (!LineTable->lookupAddressRange(Address, Size, RowVector))
505 for (uint32_t RowIndex : RowVector) {
506 // Take file number and line/column from the row.
507 const DWARFDebugLine::Row &Row = LineTable->Rows[RowIndex];
509 LineTable->getFileNameByIndex(Row.File, CU->getCompilationDir(),
510 Spec.FLIKind, Result.FileName);
511 Result.FunctionName = FunctionName;
512 Result.Line = Row.Line;
513 Result.Column = Row.Column;
514 Lines.push_back(std::make_pair(Row.Address, Result));
521 DWARFContext::getInliningInfoForAddress(uint64_t Address,
522 DILineInfoSpecifier Spec) {
523 DIInliningInfo InliningInfo;
525 DWARFCompileUnit *CU = getCompileUnitForAddress(Address);
529 const DWARFLineTable *LineTable = nullptr;
530 const DWARFDebugInfoEntryInlinedChain &InlinedChain =
531 CU->getInlinedChainForAddress(Address);
532 if (InlinedChain.DIEs.size() == 0) {
533 // If there is no DIE for address (e.g. it is in unavailable .dwo file),
534 // try to at least get file/line info from symbol table.
535 if (Spec.FLIKind != FileLineInfoKind::None) {
537 LineTable = getLineTableForUnit(CU);
539 LineTable->getFileLineInfoForAddress(Address, CU->getCompilationDir(),
540 Spec.FLIKind, Frame))
541 InliningInfo.addFrame(Frame);
546 uint32_t CallFile = 0, CallLine = 0, CallColumn = 0;
547 for (uint32_t i = 0, n = InlinedChain.DIEs.size(); i != n; i++) {
548 const DWARFDebugInfoEntryMinimal &FunctionDIE = InlinedChain.DIEs[i];
550 // Get function name if necessary.
551 if (const char *Name =
552 FunctionDIE.getSubroutineName(InlinedChain.U, Spec.FNKind))
553 Frame.FunctionName = Name;
554 if (Spec.FLIKind != FileLineInfoKind::None) {
556 // For the topmost frame, initialize the line table of this
557 // compile unit and fetch file/line info from it.
558 LineTable = getLineTableForUnit(CU);
559 // For the topmost routine, get file/line info from line table.
561 LineTable->getFileLineInfoForAddress(Address, CU->getCompilationDir(),
562 Spec.FLIKind, Frame);
564 // Otherwise, use call file, call line and call column from
565 // previous DIE in inlined chain.
567 LineTable->getFileNameByIndex(CallFile, CU->getCompilationDir(),
568 Spec.FLIKind, Frame.FileName);
569 Frame.Line = CallLine;
570 Frame.Column = CallColumn;
572 // Get call file/line/column of a current DIE.
574 FunctionDIE.getCallerFrame(InlinedChain.U, CallFile, CallLine,
578 InliningInfo.addFrame(Frame);
583 static bool consumeCompressedDebugSectionHeader(StringRef &data,
584 uint64_t &OriginalSize) {
585 // Consume "ZLIB" prefix.
586 if (!data.startswith("ZLIB"))
588 data = data.substr(4);
589 // Consume uncompressed section size (big-endian 8 bytes).
590 DataExtractor extractor(data, false, 8);
592 OriginalSize = extractor.getU64(&Offset);
595 data = data.substr(Offset);
599 DWARFContextInMemory::DWARFContextInMemory(const object::ObjectFile &Obj,
600 const LoadedObjectInfo *L)
601 : IsLittleEndian(Obj.isLittleEndian()),
602 AddressSize(Obj.getBytesInAddress()) {
603 for (const SectionRef &Section : Obj.sections()) {
605 Section.getName(name);
606 // Skip BSS and Virtual sections, they aren't interesting.
607 bool IsBSS = Section.isBSS();
610 bool IsVirtual = Section.isVirtual();
615 section_iterator RelocatedSection = Section.getRelocatedSection();
616 // Try to obtain an already relocated version of this section.
617 // Else use the unrelocated section from the object file. We'll have to
618 // apply relocations ourselves later.
619 if (!L || !L->getLoadedSectionContents(*RelocatedSection,data))
620 Section.getContents(data);
622 name = name.substr(name.find_first_not_of("._")); // Skip . and _ prefixes.
624 // Check if debug info section is compressed with zlib.
625 if (name.startswith("zdebug_")) {
626 uint64_t OriginalSize;
627 if (!zlib::isAvailable() ||
628 !consumeCompressedDebugSectionHeader(data, OriginalSize))
630 UncompressedSections.resize(UncompressedSections.size() + 1);
631 if (zlib::uncompress(data, UncompressedSections.back(), OriginalSize) !=
633 UncompressedSections.pop_back();
636 // Make data point to uncompressed section contents and save its contents.
637 name = name.substr(1);
638 data = UncompressedSections.back();
641 StringRef *SectionData =
642 StringSwitch<StringRef *>(name)
643 .Case("debug_info", &InfoSection.Data)
644 .Case("debug_abbrev", &AbbrevSection)
645 .Case("debug_loc", &LocSection.Data)
646 .Case("debug_line", &LineSection.Data)
647 .Case("debug_aranges", &ARangeSection)
648 .Case("debug_frame", &DebugFrameSection)
649 .Case("debug_str", &StringSection)
650 .Case("debug_ranges", &RangeSection)
651 .Case("debug_macinfo", &MacinfoSection)
652 .Case("debug_pubnames", &PubNamesSection)
653 .Case("debug_pubtypes", &PubTypesSection)
654 .Case("debug_gnu_pubnames", &GnuPubNamesSection)
655 .Case("debug_gnu_pubtypes", &GnuPubTypesSection)
656 .Case("debug_info.dwo", &InfoDWOSection.Data)
657 .Case("debug_abbrev.dwo", &AbbrevDWOSection)
658 .Case("debug_loc.dwo", &LocDWOSection.Data)
659 .Case("debug_line.dwo", &LineDWOSection.Data)
660 .Case("debug_str.dwo", &StringDWOSection)
661 .Case("debug_str_offsets.dwo", &StringOffsetDWOSection)
662 .Case("debug_addr", &AddrSection)
663 .Case("apple_names", &AppleNamesSection.Data)
664 .Case("apple_types", &AppleTypesSection.Data)
665 .Case("apple_namespaces", &AppleNamespacesSection.Data)
666 .Case("apple_namespac", &AppleNamespacesSection.Data)
667 .Case("apple_objc", &AppleObjCSection.Data)
668 .Case("debug_cu_index", &CUIndexSection)
669 .Case("debug_tu_index", &TUIndexSection)
670 // Any more debug info sections go here.
674 if (name == "debug_ranges") {
675 // FIXME: Use the other dwo range section when we emit it.
676 RangeDWOSection = data;
678 } else if (name == "debug_types") {
679 // Find debug_types data by section rather than name as there are
680 // multiple, comdat grouped, debug_types sections.
681 TypesSections[Section].Data = data;
682 } else if (name == "debug_types.dwo") {
683 TypesDWOSections[Section].Data = data;
686 if (RelocatedSection == Obj.section_end())
689 StringRef RelSecName;
690 StringRef RelSecData;
691 RelocatedSection->getName(RelSecName);
693 // If the section we're relocating was relocated already by the JIT,
694 // then we used the relocated version above, so we do not need to process
695 // relocations for it now.
696 if (L && L->getLoadedSectionContents(*RelocatedSection,RelSecData))
699 // In Mach-o files, the relocations do not need to be applied if
700 // there is no load offset to apply. The value read at the
701 // relocation point already factors in the section address
702 // (actually applying the relocations will produce wrong results
703 // as the section address will be added twice).
704 if (!L && dyn_cast<MachOObjectFile>(&Obj))
707 RelSecName = RelSecName.substr(
708 RelSecName.find_first_not_of("._")); // Skip . and _ prefixes.
710 // TODO: Add support for relocations in other sections as needed.
711 // Record relocations for the debug_info and debug_line sections.
712 RelocAddrMap *Map = StringSwitch<RelocAddrMap*>(RelSecName)
713 .Case("debug_info", &InfoSection.Relocs)
714 .Case("debug_loc", &LocSection.Relocs)
715 .Case("debug_info.dwo", &InfoDWOSection.Relocs)
716 .Case("debug_line", &LineSection.Relocs)
717 .Case("apple_names", &AppleNamesSection.Relocs)
718 .Case("apple_types", &AppleTypesSection.Relocs)
719 .Case("apple_namespaces", &AppleNamespacesSection.Relocs)
720 .Case("apple_namespac", &AppleNamespacesSection.Relocs)
721 .Case("apple_objc", &AppleObjCSection.Relocs)
724 // Find debug_types relocs by section rather than name as there are
725 // multiple, comdat grouped, debug_types sections.
726 if (RelSecName == "debug_types")
727 Map = &TypesSections[*RelocatedSection].Relocs;
728 else if (RelSecName == "debug_types.dwo")
729 Map = &TypesDWOSections[*RelocatedSection].Relocs;
734 if (Section.relocation_begin() != Section.relocation_end()) {
735 uint64_t SectionSize = RelocatedSection->getSize();
736 for (const RelocationRef &Reloc : Section.relocations()) {
737 uint64_t Address = Reloc.getOffset();
738 uint64_t Type = Reloc.getType();
739 uint64_t SymAddr = 0;
740 uint64_t SectionLoadAddress = 0;
741 object::symbol_iterator Sym = Reloc.getSymbol();
742 object::section_iterator RSec = Obj.section_end();
744 // First calculate the address of the symbol or section as it appears
746 if (Sym != Obj.symbol_end()) {
747 ErrorOr<uint64_t> SymAddrOrErr = Sym->getAddress();
748 if (std::error_code EC = SymAddrOrErr.getError()) {
749 errs() << "error: failed to compute symbol address: "
750 << EC.message() << '\n';
753 SymAddr = *SymAddrOrErr;
754 // Also remember what section this symbol is in for later
755 RSec = *Sym->getSection();
756 } else if (auto *MObj = dyn_cast<MachOObjectFile>(&Obj)) {
757 // MachO also has relocations that point to sections and
758 // scattered relocations.
759 auto RelocInfo = MObj->getRelocation(Reloc.getRawDataRefImpl());
760 if (MObj->isRelocationScattered(RelocInfo)) {
761 // FIXME: it's not clear how to correctly handle scattered
765 RSec = MObj->getRelocationSection(Reloc.getRawDataRefImpl());
766 SymAddr = RSec->getAddress();
770 // If we are given load addresses for the sections, we need to adjust:
771 // SymAddr = (Address of Symbol Or Section in File) -
772 // (Address of Section in File) +
773 // (Load Address of Section)
774 if (L != nullptr && RSec != Obj.section_end()) {
775 // RSec is now either the section being targeted or the section
776 // containing the symbol being targeted. In either case,
777 // we need to perform the same computation.
779 RSec->getName(SecName);
780 // llvm::dbgs() << "Name: '" << SecName
781 // << "', RSec: " << RSec->getRawDataRefImpl()
782 // << ", Section: " << Section.getRawDataRefImpl() << "\n";
783 SectionLoadAddress = L->getSectionLoadAddress(*RSec);
784 if (SectionLoadAddress != 0)
785 SymAddr += SectionLoadAddress - RSec->getAddress();
788 object::RelocVisitor V(Obj);
789 object::RelocToApply R(V.visit(Type, Reloc, SymAddr));
791 SmallString<32> Name;
792 Reloc.getTypeName(Name);
793 errs() << "error: failed to compute relocation: "
798 if (Address + R.Width > SectionSize) {
799 errs() << "error: " << R.Width << "-byte relocation starting "
800 << Address << " bytes into section " << name << " which is "
801 << SectionSize << " bytes long.\n";
805 errs() << "error: can't handle a relocation of more than 8 bytes at "
809 DEBUG(dbgs() << "Writing " << format("%p", R.Value)
810 << " at " << format("%p", Address)
811 << " with width " << format("%d", R.Width)
813 Map->insert(std::make_pair(Address, std::make_pair(R.Width, R.Value)));
819 void DWARFContextInMemory::anchor() { }