1 //===-- DWARFContext.cpp --------------------------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
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/Support/Compression.h"
16 #include "llvm/Support/Dwarf.h"
17 #include "llvm/Support/Format.h"
18 #include "llvm/Support/Path.h"
19 #include "llvm/Support/raw_ostream.h"
20 #include <algorithm>
21 using namespace llvm;
22 using namespace dwarf;
23 using namespace object;
24
25 #define DEBUG_TYPE "dwarf"
26
27 typedef DWARFDebugLine::LineTable DWARFLineTable;
28 typedef DILineInfoSpecifier::FileLineInfoKind FileLineInfoKind;
29 typedef DILineInfoSpecifier::FunctionNameKind FunctionNameKind;
30
dumpPubSection(raw_ostream & OS,StringRef Name,StringRef Data,bool LittleEndian,bool GnuStyle)31 static void dumpPubSection(raw_ostream &OS, StringRef Name, StringRef Data,
32 bool LittleEndian, bool GnuStyle) {
33 OS << "\n." << Name << " contents:\n";
34 DataExtractor pubNames(Data, LittleEndian, 0);
35 uint32_t offset = 0;
36 while (pubNames.isValidOffset(offset)) {
37 OS << "length = " << format("0x%08x", pubNames.getU32(&offset));
38 OS << " version = " << format("0x%04x", pubNames.getU16(&offset));
39 OS << " unit_offset = " << format("0x%08x", pubNames.getU32(&offset));
40 OS << " unit_size = " << format("0x%08x", pubNames.getU32(&offset)) << '\n';
41 if (GnuStyle)
42 OS << "Offset Linkage Kind Name\n";
43 else
44 OS << "Offset Name\n";
45
46 while (offset < Data.size()) {
47 uint32_t dieRef = pubNames.getU32(&offset);
48 if (dieRef == 0)
49 break;
50 OS << format("0x%8.8x ", dieRef);
51 if (GnuStyle) {
52 PubIndexEntryDescriptor desc(pubNames.getU8(&offset));
53 OS << format("%-8s", dwarf::GDBIndexEntryLinkageString(desc.Linkage))
54 << ' ' << format("%-8s", dwarf::GDBIndexEntryKindString(desc.Kind))
55 << ' ';
56 }
57 OS << '\"' << pubNames.getCStr(&offset) << "\"\n";
58 }
59 }
60 }
61
dumpAccelSection(raw_ostream & OS,StringRef Name,const DWARFSection & Section,StringRef StringSection,bool LittleEndian)62 static void dumpAccelSection(raw_ostream &OS, StringRef Name,
63 const DWARFSection& Section, StringRef StringSection,
64 bool LittleEndian) {
65 DataExtractor AccelSection(Section.Data, LittleEndian, 0);
66 DataExtractor StrData(StringSection, LittleEndian, 0);
67 OS << "\n." << Name << " contents:\n";
68 DWARFAcceleratorTable Accel(AccelSection, StrData, Section.Relocs);
69 if (!Accel.extract())
70 return;
71 Accel.dump(OS);
72 }
73
dump(raw_ostream & OS,DIDumpType DumpType)74 void DWARFContext::dump(raw_ostream &OS, DIDumpType DumpType) {
75 if (DumpType == DIDT_All || DumpType == DIDT_Abbrev) {
76 OS << ".debug_abbrev contents:\n";
77 getDebugAbbrev()->dump(OS);
78 }
79
80 if (DumpType == DIDT_All || DumpType == DIDT_AbbrevDwo)
81 if (const DWARFDebugAbbrev *D = getDebugAbbrevDWO()) {
82 OS << "\n.debug_abbrev.dwo contents:\n";
83 D->dump(OS);
84 }
85
86 if (DumpType == DIDT_All || DumpType == DIDT_Info) {
87 OS << "\n.debug_info contents:\n";
88 for (const auto &CU : compile_units())
89 CU->dump(OS);
90 }
91
92 if ((DumpType == DIDT_All || DumpType == DIDT_InfoDwo) &&
93 getNumDWOCompileUnits()) {
94 OS << "\n.debug_info.dwo contents:\n";
95 for (const auto &DWOCU : dwo_compile_units())
96 DWOCU->dump(OS);
97 }
98
99 if ((DumpType == DIDT_All || DumpType == DIDT_Types) && getNumTypeUnits()) {
100 OS << "\n.debug_types contents:\n";
101 for (const auto &TUS : type_unit_sections())
102 for (const auto &TU : TUS)
103 TU->dump(OS);
104 }
105
106 if ((DumpType == DIDT_All || DumpType == DIDT_TypesDwo) &&
107 getNumDWOTypeUnits()) {
108 OS << "\n.debug_types.dwo contents:\n";
109 for (const auto &DWOTUS : dwo_type_unit_sections())
110 for (const auto &DWOTU : DWOTUS)
111 DWOTU->dump(OS);
112 }
113
114 if (DumpType == DIDT_All || DumpType == DIDT_Loc) {
115 OS << "\n.debug_loc contents:\n";
116 getDebugLoc()->dump(OS);
117 }
118
119 if (DumpType == DIDT_All || DumpType == DIDT_LocDwo) {
120 OS << "\n.debug_loc.dwo contents:\n";
121 getDebugLocDWO()->dump(OS);
122 }
123
124 if (DumpType == DIDT_All || DumpType == DIDT_Frames) {
125 OS << "\n.debug_frame contents:\n";
126 getDebugFrame()->dump(OS);
127 }
128
129 uint32_t offset = 0;
130 if (DumpType == DIDT_All || DumpType == DIDT_Aranges) {
131 OS << "\n.debug_aranges contents:\n";
132 DataExtractor arangesData(getARangeSection(), isLittleEndian(), 0);
133 DWARFDebugArangeSet set;
134 while (set.extract(arangesData, &offset))
135 set.dump(OS);
136 }
137
138 uint8_t savedAddressByteSize = 0;
139 if (DumpType == DIDT_All || DumpType == DIDT_Line) {
140 OS << "\n.debug_line contents:\n";
141 for (const auto &CU : compile_units()) {
142 savedAddressByteSize = CU->getAddressByteSize();
143 unsigned stmtOffset =
144 CU->getCompileUnitDIE()->getAttributeValueAsSectionOffset(
145 CU.get(), DW_AT_stmt_list, -1U);
146 if (stmtOffset != -1U) {
147 DataExtractor lineData(getLineSection().Data, isLittleEndian(),
148 savedAddressByteSize);
149 DWARFDebugLine::LineTable LineTable;
150 LineTable.parse(lineData, &getLineSection().Relocs, &stmtOffset);
151 LineTable.dump(OS);
152 }
153 }
154 }
155
156 if (DumpType == DIDT_All || DumpType == DIDT_LineDwo) {
157 OS << "\n.debug_line.dwo contents:\n";
158 unsigned stmtOffset = 0;
159 DataExtractor lineData(getLineDWOSection().Data, isLittleEndian(),
160 savedAddressByteSize);
161 DWARFDebugLine::LineTable LineTable;
162 while (LineTable.Prologue.parse(lineData, &stmtOffset)) {
163 LineTable.dump(OS);
164 LineTable.clear();
165 }
166 }
167
168 if (DumpType == DIDT_All || DumpType == DIDT_Str) {
169 OS << "\n.debug_str contents:\n";
170 DataExtractor strData(getStringSection(), isLittleEndian(), 0);
171 offset = 0;
172 uint32_t strOffset = 0;
173 while (const char *s = strData.getCStr(&offset)) {
174 OS << format("0x%8.8x: \"%s\"\n", strOffset, s);
175 strOffset = offset;
176 }
177 }
178
179 if ((DumpType == DIDT_All || DumpType == DIDT_StrDwo) &&
180 !getStringDWOSection().empty()) {
181 OS << "\n.debug_str.dwo contents:\n";
182 DataExtractor strDWOData(getStringDWOSection(), isLittleEndian(), 0);
183 offset = 0;
184 uint32_t strDWOOffset = 0;
185 while (const char *s = strDWOData.getCStr(&offset)) {
186 OS << format("0x%8.8x: \"%s\"\n", strDWOOffset, s);
187 strDWOOffset = offset;
188 }
189 }
190
191 if (DumpType == DIDT_All || DumpType == DIDT_Ranges) {
192 OS << "\n.debug_ranges contents:\n";
193 // In fact, different compile units may have different address byte
194 // sizes, but for simplicity we just use the address byte size of the last
195 // compile unit (there is no easy and fast way to associate address range
196 // list and the compile unit it describes).
197 DataExtractor rangesData(getRangeSection(), isLittleEndian(),
198 savedAddressByteSize);
199 offset = 0;
200 DWARFDebugRangeList rangeList;
201 while (rangeList.extract(rangesData, &offset))
202 rangeList.dump(OS);
203 }
204
205 if (DumpType == DIDT_All || DumpType == DIDT_Pubnames)
206 dumpPubSection(OS, "debug_pubnames", getPubNamesSection(),
207 isLittleEndian(), false);
208
209 if (DumpType == DIDT_All || DumpType == DIDT_Pubtypes)
210 dumpPubSection(OS, "debug_pubtypes", getPubTypesSection(),
211 isLittleEndian(), false);
212
213 if (DumpType == DIDT_All || DumpType == DIDT_GnuPubnames)
214 dumpPubSection(OS, "debug_gnu_pubnames", getGnuPubNamesSection(),
215 isLittleEndian(), true /* GnuStyle */);
216
217 if (DumpType == DIDT_All || DumpType == DIDT_GnuPubtypes)
218 dumpPubSection(OS, "debug_gnu_pubtypes", getGnuPubTypesSection(),
219 isLittleEndian(), true /* GnuStyle */);
220
221 if ((DumpType == DIDT_All || DumpType == DIDT_StrOffsetsDwo) &&
222 !getStringOffsetDWOSection().empty()) {
223 OS << "\n.debug_str_offsets.dwo contents:\n";
224 DataExtractor strOffsetExt(getStringOffsetDWOSection(), isLittleEndian(),
225 0);
226 offset = 0;
227 uint64_t size = getStringOffsetDWOSection().size();
228 while (offset < size) {
229 OS << format("0x%8.8x: ", offset);
230 OS << format("%8.8x\n", strOffsetExt.getU32(&offset));
231 }
232 }
233
234 if (DumpType == DIDT_All || DumpType == DIDT_AppleNames)
235 dumpAccelSection(OS, "apple_names", getAppleNamesSection(),
236 getStringSection(), isLittleEndian());
237
238 if (DumpType == DIDT_All || DumpType == DIDT_AppleTypes)
239 dumpAccelSection(OS, "apple_types", getAppleTypesSection(),
240 getStringSection(), isLittleEndian());
241
242 if (DumpType == DIDT_All || DumpType == DIDT_AppleNamespaces)
243 dumpAccelSection(OS, "apple_namespaces", getAppleNamespacesSection(),
244 getStringSection(), isLittleEndian());
245
246 if (DumpType == DIDT_All || DumpType == DIDT_AppleObjC)
247 dumpAccelSection(OS, "apple_objc", getAppleObjCSection(),
248 getStringSection(), isLittleEndian());
249 }
250
getDebugAbbrev()251 const DWARFDebugAbbrev *DWARFContext::getDebugAbbrev() {
252 if (Abbrev)
253 return Abbrev.get();
254
255 DataExtractor abbrData(getAbbrevSection(), isLittleEndian(), 0);
256
257 Abbrev.reset(new DWARFDebugAbbrev());
258 Abbrev->extract(abbrData);
259 return Abbrev.get();
260 }
261
getDebugAbbrevDWO()262 const DWARFDebugAbbrev *DWARFContext::getDebugAbbrevDWO() {
263 if (AbbrevDWO)
264 return AbbrevDWO.get();
265
266 DataExtractor abbrData(getAbbrevDWOSection(), isLittleEndian(), 0);
267 AbbrevDWO.reset(new DWARFDebugAbbrev());
268 AbbrevDWO->extract(abbrData);
269 return AbbrevDWO.get();
270 }
271
getDebugLoc()272 const DWARFDebugLoc *DWARFContext::getDebugLoc() {
273 if (Loc)
274 return Loc.get();
275
276 DataExtractor LocData(getLocSection().Data, isLittleEndian(), 0);
277 Loc.reset(new DWARFDebugLoc(getLocSection().Relocs));
278 // assume all compile units have the same address byte size
279 if (getNumCompileUnits())
280 Loc->parse(LocData, getCompileUnitAtIndex(0)->getAddressByteSize());
281 return Loc.get();
282 }
283
getDebugLocDWO()284 const DWARFDebugLocDWO *DWARFContext::getDebugLocDWO() {
285 if (LocDWO)
286 return LocDWO.get();
287
288 DataExtractor LocData(getLocDWOSection().Data, isLittleEndian(), 0);
289 LocDWO.reset(new DWARFDebugLocDWO());
290 LocDWO->parse(LocData);
291 return LocDWO.get();
292 }
293
getDebugAranges()294 const DWARFDebugAranges *DWARFContext::getDebugAranges() {
295 if (Aranges)
296 return Aranges.get();
297
298 Aranges.reset(new DWARFDebugAranges());
299 Aranges->generate(this);
300 return Aranges.get();
301 }
302
getDebugFrame()303 const DWARFDebugFrame *DWARFContext::getDebugFrame() {
304 if (DebugFrame)
305 return DebugFrame.get();
306
307 // There's a "bug" in the DWARFv3 standard with respect to the target address
308 // size within debug frame sections. While DWARF is supposed to be independent
309 // of its container, FDEs have fields with size being "target address size",
310 // which isn't specified in DWARF in general. It's only specified for CUs, but
311 // .eh_frame can appear without a .debug_info section. Follow the example of
312 // other tools (libdwarf) and extract this from the container (ObjectFile
313 // provides this information). This problem is fixed in DWARFv4
314 // See this dwarf-discuss discussion for more details:
315 // http://lists.dwarfstd.org/htdig.cgi/dwarf-discuss-dwarfstd.org/2011-December/001173.html
316 DataExtractor debugFrameData(getDebugFrameSection(), isLittleEndian(),
317 getAddressSize());
318 DebugFrame.reset(new DWARFDebugFrame());
319 DebugFrame->parse(debugFrameData);
320 return DebugFrame.get();
321 }
322
323 const DWARFLineTable *
getLineTableForUnit(DWARFUnit * cu)324 DWARFContext::getLineTableForUnit(DWARFUnit *cu) {
325 if (!Line)
326 Line.reset(new DWARFDebugLine(&getLineSection().Relocs));
327
328 unsigned stmtOffset =
329 cu->getCompileUnitDIE()->getAttributeValueAsSectionOffset(
330 cu, DW_AT_stmt_list, -1U);
331 if (stmtOffset == -1U)
332 return nullptr; // No line table for this compile unit.
333
334 // See if the line table is cached.
335 if (const DWARFLineTable *lt = Line->getLineTable(stmtOffset))
336 return lt;
337
338 // We have to parse it first.
339 DataExtractor lineData(getLineSection().Data, isLittleEndian(),
340 cu->getAddressByteSize());
341 return Line->getOrParseLineTable(lineData, stmtOffset);
342 }
343
parseCompileUnits()344 void DWARFContext::parseCompileUnits() {
345 CUs.parse(*this, getInfoSection());
346 }
347
parseTypeUnits()348 void DWARFContext::parseTypeUnits() {
349 if (!TUs.empty())
350 return;
351 for (const auto &I : getTypesSections()) {
352 TUs.push_back(DWARFUnitSection<DWARFTypeUnit>());
353 TUs.back().parse(*this, I.second);
354 }
355 }
356
parseDWOCompileUnits()357 void DWARFContext::parseDWOCompileUnits() {
358 DWOCUs.parseDWO(*this, getInfoDWOSection());
359 }
360
parseDWOTypeUnits()361 void DWARFContext::parseDWOTypeUnits() {
362 if (!DWOTUs.empty())
363 return;
364 for (const auto &I : getTypesDWOSections()) {
365 DWOTUs.push_back(DWARFUnitSection<DWARFTypeUnit>());
366 DWOTUs.back().parseDWO(*this, I.second);
367 }
368 }
369
getCompileUnitForOffset(uint32_t Offset)370 DWARFCompileUnit *DWARFContext::getCompileUnitForOffset(uint32_t Offset) {
371 parseCompileUnits();
372 return CUs.getUnitForOffset(Offset);
373 }
374
getCompileUnitForAddress(uint64_t Address)375 DWARFCompileUnit *DWARFContext::getCompileUnitForAddress(uint64_t Address) {
376 // First, get the offset of the compile unit.
377 uint32_t CUOffset = getDebugAranges()->findAddress(Address);
378 // Retrieve the compile unit.
379 return getCompileUnitForOffset(CUOffset);
380 }
381
getFunctionNameForAddress(DWARFCompileUnit * CU,uint64_t Address,FunctionNameKind Kind,std::string & FunctionName)382 static bool getFunctionNameForAddress(DWARFCompileUnit *CU, uint64_t Address,
383 FunctionNameKind Kind,
384 std::string &FunctionName) {
385 if (Kind == FunctionNameKind::None)
386 return false;
387 // The address may correspond to instruction in some inlined function,
388 // so we have to build the chain of inlined functions and take the
389 // name of the topmost function in it.
390 const DWARFDebugInfoEntryInlinedChain &InlinedChain =
391 CU->getInlinedChainForAddress(Address);
392 if (InlinedChain.DIEs.size() == 0)
393 return false;
394 const DWARFDebugInfoEntryMinimal &TopFunctionDIE = InlinedChain.DIEs[0];
395 if (const char *Name =
396 TopFunctionDIE.getSubroutineName(InlinedChain.U, Kind)) {
397 FunctionName = Name;
398 return true;
399 }
400 return false;
401 }
402
getLineInfoForAddress(uint64_t Address,DILineInfoSpecifier Spec)403 DILineInfo DWARFContext::getLineInfoForAddress(uint64_t Address,
404 DILineInfoSpecifier Spec) {
405 DILineInfo Result;
406
407 DWARFCompileUnit *CU = getCompileUnitForAddress(Address);
408 if (!CU)
409 return Result;
410 getFunctionNameForAddress(CU, Address, Spec.FNKind, Result.FunctionName);
411 if (Spec.FLIKind != FileLineInfoKind::None) {
412 if (const DWARFLineTable *LineTable = getLineTableForUnit(CU))
413 LineTable->getFileLineInfoForAddress(Address, CU->getCompilationDir(),
414 Spec.FLIKind, Result);
415 }
416 return Result;
417 }
418
419 DILineInfoTable
getLineInfoForAddressRange(uint64_t Address,uint64_t Size,DILineInfoSpecifier Spec)420 DWARFContext::getLineInfoForAddressRange(uint64_t Address, uint64_t Size,
421 DILineInfoSpecifier Spec) {
422 DILineInfoTable Lines;
423 DWARFCompileUnit *CU = getCompileUnitForAddress(Address);
424 if (!CU)
425 return Lines;
426
427 std::string FunctionName = "<invalid>";
428 getFunctionNameForAddress(CU, Address, Spec.FNKind, FunctionName);
429
430 // If the Specifier says we don't need FileLineInfo, just
431 // return the top-most function at the starting address.
432 if (Spec.FLIKind == FileLineInfoKind::None) {
433 DILineInfo Result;
434 Result.FunctionName = FunctionName;
435 Lines.push_back(std::make_pair(Address, Result));
436 return Lines;
437 }
438
439 const DWARFLineTable *LineTable = getLineTableForUnit(CU);
440
441 // Get the index of row we're looking for in the line table.
442 std::vector<uint32_t> RowVector;
443 if (!LineTable->lookupAddressRange(Address, Size, RowVector))
444 return Lines;
445
446 for (uint32_t RowIndex : RowVector) {
447 // Take file number and line/column from the row.
448 const DWARFDebugLine::Row &Row = LineTable->Rows[RowIndex];
449 DILineInfo Result;
450 LineTable->getFileNameByIndex(Row.File, CU->getCompilationDir(),
451 Spec.FLIKind, Result.FileName);
452 Result.FunctionName = FunctionName;
453 Result.Line = Row.Line;
454 Result.Column = Row.Column;
455 Lines.push_back(std::make_pair(Row.Address, Result));
456 }
457
458 return Lines;
459 }
460
461 DIInliningInfo
getInliningInfoForAddress(uint64_t Address,DILineInfoSpecifier Spec)462 DWARFContext::getInliningInfoForAddress(uint64_t Address,
463 DILineInfoSpecifier Spec) {
464 DIInliningInfo InliningInfo;
465
466 DWARFCompileUnit *CU = getCompileUnitForAddress(Address);
467 if (!CU)
468 return InliningInfo;
469
470 const DWARFLineTable *LineTable = nullptr;
471 const DWARFDebugInfoEntryInlinedChain &InlinedChain =
472 CU->getInlinedChainForAddress(Address);
473 if (InlinedChain.DIEs.size() == 0) {
474 // If there is no DIE for address (e.g. it is in unavailable .dwo file),
475 // try to at least get file/line info from symbol table.
476 if (Spec.FLIKind != FileLineInfoKind::None) {
477 DILineInfo Frame;
478 LineTable = getLineTableForUnit(CU);
479 if (LineTable &&
480 LineTable->getFileLineInfoForAddress(Address, CU->getCompilationDir(),
481 Spec.FLIKind, Frame))
482 InliningInfo.addFrame(Frame);
483 }
484 return InliningInfo;
485 }
486
487 uint32_t CallFile = 0, CallLine = 0, CallColumn = 0;
488 for (uint32_t i = 0, n = InlinedChain.DIEs.size(); i != n; i++) {
489 const DWARFDebugInfoEntryMinimal &FunctionDIE = InlinedChain.DIEs[i];
490 DILineInfo Frame;
491 // Get function name if necessary.
492 if (const char *Name =
493 FunctionDIE.getSubroutineName(InlinedChain.U, Spec.FNKind))
494 Frame.FunctionName = Name;
495 if (Spec.FLIKind != FileLineInfoKind::None) {
496 if (i == 0) {
497 // For the topmost frame, initialize the line table of this
498 // compile unit and fetch file/line info from it.
499 LineTable = getLineTableForUnit(CU);
500 // For the topmost routine, get file/line info from line table.
501 if (LineTable)
502 LineTable->getFileLineInfoForAddress(Address, CU->getCompilationDir(),
503 Spec.FLIKind, Frame);
504 } else {
505 // Otherwise, use call file, call line and call column from
506 // previous DIE in inlined chain.
507 if (LineTable)
508 LineTable->getFileNameByIndex(CallFile, CU->getCompilationDir(),
509 Spec.FLIKind, Frame.FileName);
510 Frame.Line = CallLine;
511 Frame.Column = CallColumn;
512 }
513 // Get call file/line/column of a current DIE.
514 if (i + 1 < n) {
515 FunctionDIE.getCallerFrame(InlinedChain.U, CallFile, CallLine,
516 CallColumn);
517 }
518 }
519 InliningInfo.addFrame(Frame);
520 }
521 return InliningInfo;
522 }
523
consumeCompressedDebugSectionHeader(StringRef & data,uint64_t & OriginalSize)524 static bool consumeCompressedDebugSectionHeader(StringRef &data,
525 uint64_t &OriginalSize) {
526 // Consume "ZLIB" prefix.
527 if (!data.startswith("ZLIB"))
528 return false;
529 data = data.substr(4);
530 // Consume uncompressed section size (big-endian 8 bytes).
531 DataExtractor extractor(data, false, 8);
532 uint32_t Offset = 0;
533 OriginalSize = extractor.getU64(&Offset);
534 if (Offset == 0)
535 return false;
536 data = data.substr(Offset);
537 return true;
538 }
539
DWARFContextInMemory(const object::ObjectFile & Obj)540 DWARFContextInMemory::DWARFContextInMemory(const object::ObjectFile &Obj)
541 : IsLittleEndian(Obj.isLittleEndian()),
542 AddressSize(Obj.getBytesInAddress()) {
543 for (const SectionRef &Section : Obj.sections()) {
544 StringRef name;
545 Section.getName(name);
546 // Skip BSS and Virtual sections, they aren't interesting.
547 bool IsBSS = Section.isBSS();
548 if (IsBSS)
549 continue;
550 bool IsVirtual = Section.isVirtual();
551 if (IsVirtual)
552 continue;
553 StringRef data;
554 Section.getContents(data);
555
556 name = name.substr(name.find_first_not_of("._")); // Skip . and _ prefixes.
557
558 // Check if debug info section is compressed with zlib.
559 if (name.startswith("zdebug_")) {
560 uint64_t OriginalSize;
561 if (!zlib::isAvailable() ||
562 !consumeCompressedDebugSectionHeader(data, OriginalSize))
563 continue;
564 UncompressedSections.resize(UncompressedSections.size() + 1);
565 if (zlib::uncompress(data, UncompressedSections.back(), OriginalSize) !=
566 zlib::StatusOK) {
567 UncompressedSections.pop_back();
568 continue;
569 }
570 // Make data point to uncompressed section contents and save its contents.
571 name = name.substr(1);
572 data = UncompressedSections.back();
573 }
574
575 StringRef *SectionData =
576 StringSwitch<StringRef *>(name)
577 .Case("debug_info", &InfoSection.Data)
578 .Case("debug_abbrev", &AbbrevSection)
579 .Case("debug_loc", &LocSection.Data)
580 .Case("debug_line", &LineSection.Data)
581 .Case("debug_aranges", &ARangeSection)
582 .Case("debug_frame", &DebugFrameSection)
583 .Case("debug_str", &StringSection)
584 .Case("debug_ranges", &RangeSection)
585 .Case("debug_pubnames", &PubNamesSection)
586 .Case("debug_pubtypes", &PubTypesSection)
587 .Case("debug_gnu_pubnames", &GnuPubNamesSection)
588 .Case("debug_gnu_pubtypes", &GnuPubTypesSection)
589 .Case("debug_info.dwo", &InfoDWOSection.Data)
590 .Case("debug_abbrev.dwo", &AbbrevDWOSection)
591 .Case("debug_loc.dwo", &LocDWOSection.Data)
592 .Case("debug_line.dwo", &LineDWOSection.Data)
593 .Case("debug_str.dwo", &StringDWOSection)
594 .Case("debug_str_offsets.dwo", &StringOffsetDWOSection)
595 .Case("debug_addr", &AddrSection)
596 .Case("apple_names", &AppleNamesSection.Data)
597 .Case("apple_types", &AppleTypesSection.Data)
598 .Case("apple_namespaces", &AppleNamespacesSection.Data)
599 .Case("apple_namespac", &AppleNamespacesSection.Data)
600 .Case("apple_objc", &AppleObjCSection.Data)
601 // Any more debug info sections go here.
602 .Default(nullptr);
603 if (SectionData) {
604 *SectionData = data;
605 if (name == "debug_ranges") {
606 // FIXME: Use the other dwo range section when we emit it.
607 RangeDWOSection = data;
608 }
609 } else if (name == "debug_types") {
610 // Find debug_types data by section rather than name as there are
611 // multiple, comdat grouped, debug_types sections.
612 TypesSections[Section].Data = data;
613 } else if (name == "debug_types.dwo") {
614 TypesDWOSections[Section].Data = data;
615 }
616
617 section_iterator RelocatedSection = Section.getRelocatedSection();
618 if (RelocatedSection == Obj.section_end())
619 continue;
620
621 StringRef RelSecName;
622 RelocatedSection->getName(RelSecName);
623 RelSecName = RelSecName.substr(
624 RelSecName.find_first_not_of("._")); // Skip . and _ prefixes.
625
626 // TODO: Add support for relocations in other sections as needed.
627 // Record relocations for the debug_info and debug_line sections.
628 RelocAddrMap *Map = StringSwitch<RelocAddrMap*>(RelSecName)
629 .Case("debug_info", &InfoSection.Relocs)
630 .Case("debug_loc", &LocSection.Relocs)
631 .Case("debug_info.dwo", &InfoDWOSection.Relocs)
632 .Case("debug_line", &LineSection.Relocs)
633 .Case("apple_names", &AppleNamesSection.Relocs)
634 .Case("apple_types", &AppleTypesSection.Relocs)
635 .Case("apple_namespaces", &AppleNamespacesSection.Relocs)
636 .Case("apple_namespac", &AppleNamespacesSection.Relocs)
637 .Case("apple_objc", &AppleObjCSection.Relocs)
638 .Default(nullptr);
639 if (!Map) {
640 // Find debug_types relocs by section rather than name as there are
641 // multiple, comdat grouped, debug_types sections.
642 if (RelSecName == "debug_types")
643 Map = &TypesSections[*RelocatedSection].Relocs;
644 else if (RelSecName == "debug_types.dwo")
645 Map = &TypesDWOSections[*RelocatedSection].Relocs;
646 else
647 continue;
648 }
649
650 if (Section.relocation_begin() != Section.relocation_end()) {
651 uint64_t SectionSize = RelocatedSection->getSize();
652 for (const RelocationRef &Reloc : Section.relocations()) {
653 uint64_t Address;
654 Reloc.getOffset(Address);
655 uint64_t Type;
656 Reloc.getType(Type);
657 uint64_t SymAddr = 0;
658 object::symbol_iterator Sym = Reloc.getSymbol();
659 if (Sym != Obj.symbol_end())
660 Sym->getAddress(SymAddr);
661
662 object::RelocVisitor V(Obj);
663 object::RelocToApply R(V.visit(Type, Reloc, SymAddr));
664 if (V.error()) {
665 SmallString<32> Name;
666 std::error_code ec(Reloc.getTypeName(Name));
667 if (ec) {
668 errs() << "Aaaaaa! Nameless relocation! Aaaaaa!\n";
669 }
670 errs() << "error: failed to compute relocation: "
671 << Name << "\n";
672 continue;
673 }
674
675 if (Address + R.Width > SectionSize) {
676 errs() << "error: " << R.Width << "-byte relocation starting "
677 << Address << " bytes into section " << name << " which is "
678 << SectionSize << " bytes long.\n";
679 continue;
680 }
681 if (R.Width > 8) {
682 errs() << "error: can't handle a relocation of more than 8 bytes at "
683 "a time.\n";
684 continue;
685 }
686 DEBUG(dbgs() << "Writing " << format("%p", R.Value)
687 << " at " << format("%p", Address)
688 << " with width " << format("%d", R.Width)
689 << "\n");
690 Map->insert(std::make_pair(Address, std::make_pair(R.Width, R.Value)));
691 }
692 }
693 }
694 }
695
anchor()696 void DWARFContextInMemory::anchor() { }
697