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/DebugInfo/DWARF/DWARFUnitIndex.h" 16 #include "llvm/Object/MachO.h" 17 #include "llvm/Object/RelocVisitor.h" 18 #include "llvm/Support/Compression.h" 19 #include "llvm/Support/Dwarf.h" 20 #include "llvm/Support/ELF.h" 21 #include "llvm/Support/Format.h" 22 #include "llvm/Support/Path.h" 23 #include "llvm/Support/raw_ostream.h" 24 #include <algorithm> 25 using namespace llvm; 26 using namespace dwarf; 27 using namespace object; 28 29 #define DEBUG_TYPE "dwarf" 30 31 typedef DWARFDebugLine::LineTable DWARFLineTable; 32 typedef DILineInfoSpecifier::FileLineInfoKind FileLineInfoKind; 33 typedef DILineInfoSpecifier::FunctionNameKind FunctionNameKind; 34 35 static void dumpPubSection(raw_ostream &OS, StringRef Name, StringRef Data, 36 bool LittleEndian, bool GnuStyle) { 37 OS << "\n." << Name << " contents:\n"; 38 DataExtractor pubNames(Data, LittleEndian, 0); 39 uint32_t offset = 0; 40 while (pubNames.isValidOffset(offset)) { 41 OS << "length = " << format("0x%08x", pubNames.getU32(&offset)); 42 OS << " version = " << format("0x%04x", pubNames.getU16(&offset)); 43 OS << " unit_offset = " << format("0x%08x", pubNames.getU32(&offset)); 44 OS << " unit_size = " << format("0x%08x", pubNames.getU32(&offset)) << '\n'; 45 if (GnuStyle) 46 OS << "Offset Linkage Kind Name\n"; 47 else 48 OS << "Offset Name\n"; 49 50 while (offset < Data.size()) { 51 uint32_t dieRef = pubNames.getU32(&offset); 52 if (dieRef == 0) 53 break; 54 OS << format("0x%8.8x ", dieRef); 55 if (GnuStyle) { 56 PubIndexEntryDescriptor desc(pubNames.getU8(&offset)); 57 OS << format("%-8s", dwarf::GDBIndexEntryLinkageString(desc.Linkage)) 58 << ' ' << format("%-8s", dwarf::GDBIndexEntryKindString(desc.Kind)) 59 << ' '; 60 } 61 OS << '\"' << pubNames.getCStr(&offset) << "\"\n"; 62 } 63 } 64 } 65 66 static void dumpAccelSection(raw_ostream &OS, StringRef Name, 67 const DWARFSection& Section, StringRef StringSection, 68 bool LittleEndian) { 69 DataExtractor AccelSection(Section.Data, LittleEndian, 0); 70 DataExtractor StrData(StringSection, LittleEndian, 0); 71 OS << "\n." << Name << " contents:\n"; 72 DWARFAcceleratorTable Accel(AccelSection, StrData, Section.Relocs); 73 if (!Accel.extract()) 74 return; 75 Accel.dump(OS); 76 } 77 78 void DWARFContext::dump(raw_ostream &OS, DIDumpType DumpType, bool DumpEH) { 79 if (DumpType == DIDT_All || DumpType == DIDT_Abbrev) { 80 OS << ".debug_abbrev contents:\n"; 81 getDebugAbbrev()->dump(OS); 82 } 83 84 if (DumpType == DIDT_All || DumpType == DIDT_AbbrevDwo) 85 if (const DWARFDebugAbbrev *D = getDebugAbbrevDWO()) { 86 OS << "\n.debug_abbrev.dwo contents:\n"; 87 D->dump(OS); 88 } 89 90 if (DumpType == DIDT_All || DumpType == DIDT_Info) { 91 OS << "\n.debug_info contents:\n"; 92 for (const auto &CU : compile_units()) 93 CU->dump(OS); 94 } 95 96 if ((DumpType == DIDT_All || DumpType == DIDT_InfoDwo) && 97 getNumDWOCompileUnits()) { 98 OS << "\n.debug_info.dwo contents:\n"; 99 for (const auto &DWOCU : dwo_compile_units()) 100 DWOCU->dump(OS); 101 } 102 103 if ((DumpType == DIDT_All || DumpType == DIDT_Types) && getNumTypeUnits()) { 104 OS << "\n.debug_types contents:\n"; 105 for (const auto &TUS : type_unit_sections()) 106 for (const auto &TU : TUS) 107 TU->dump(OS); 108 } 109 110 if ((DumpType == DIDT_All || DumpType == DIDT_TypesDwo) && 111 getNumDWOTypeUnits()) { 112 OS << "\n.debug_types.dwo contents:\n"; 113 for (const auto &DWOTUS : dwo_type_unit_sections()) 114 for (const auto &DWOTU : DWOTUS) 115 DWOTU->dump(OS); 116 } 117 118 if (DumpType == DIDT_All || DumpType == DIDT_Loc) { 119 OS << "\n.debug_loc contents:\n"; 120 getDebugLoc()->dump(OS); 121 } 122 123 if (DumpType == DIDT_All || DumpType == DIDT_LocDwo) { 124 OS << "\n.debug_loc.dwo contents:\n"; 125 getDebugLocDWO()->dump(OS); 126 } 127 128 if (DumpType == DIDT_All || DumpType == DIDT_Frames) { 129 OS << "\n.debug_frame contents:\n"; 130 getDebugFrame()->dump(OS); 131 if (DumpEH) { 132 OS << "\n.eh_frame contents:\n"; 133 getEHFrame()->dump(OS); 134 } 135 } 136 137 if (DumpType == DIDT_All || DumpType == DIDT_Macro) { 138 OS << "\n.debug_macinfo contents:\n"; 139 getDebugMacro()->dump(OS); 140 } 141 142 uint32_t offset = 0; 143 if (DumpType == DIDT_All || DumpType == DIDT_Aranges) { 144 OS << "\n.debug_aranges contents:\n"; 145 DataExtractor arangesData(getARangeSection(), isLittleEndian(), 0); 146 DWARFDebugArangeSet set; 147 while (set.extract(arangesData, &offset)) 148 set.dump(OS); 149 } 150 151 uint8_t savedAddressByteSize = 0; 152 if (DumpType == DIDT_All || DumpType == DIDT_Line) { 153 OS << "\n.debug_line contents:\n"; 154 for (const auto &CU : compile_units()) { 155 savedAddressByteSize = CU->getAddressByteSize(); 156 const auto *CUDIE = CU->getUnitDIE(); 157 if (CUDIE == nullptr) 158 continue; 159 unsigned stmtOffset = CUDIE->getAttributeValueAsSectionOffset( 160 CU.get(), DW_AT_stmt_list, -1U); 161 if (stmtOffset != -1U) { 162 DataExtractor lineData(getLineSection().Data, isLittleEndian(), 163 savedAddressByteSize); 164 DWARFDebugLine::LineTable LineTable; 165 LineTable.parse(lineData, &getLineSection().Relocs, &stmtOffset); 166 LineTable.dump(OS); 167 } 168 } 169 } 170 171 if (DumpType == DIDT_All || DumpType == DIDT_CUIndex) { 172 OS << "\n.debug_cu_index contents:\n"; 173 getCUIndex().dump(OS); 174 } 175 176 if (DumpType == DIDT_All || DumpType == DIDT_TUIndex) { 177 OS << "\n.debug_tu_index contents:\n"; 178 getTUIndex().dump(OS); 179 } 180 181 if (DumpType == DIDT_All || DumpType == DIDT_LineDwo) { 182 OS << "\n.debug_line.dwo contents:\n"; 183 unsigned stmtOffset = 0; 184 DataExtractor lineData(getLineDWOSection().Data, isLittleEndian(), 185 savedAddressByteSize); 186 DWARFDebugLine::LineTable LineTable; 187 while (LineTable.Prologue.parse(lineData, &stmtOffset)) { 188 LineTable.dump(OS); 189 LineTable.clear(); 190 } 191 } 192 193 if (DumpType == DIDT_All || DumpType == DIDT_Str) { 194 OS << "\n.debug_str contents:\n"; 195 DataExtractor strData(getStringSection(), isLittleEndian(), 0); 196 offset = 0; 197 uint32_t strOffset = 0; 198 while (const char *s = strData.getCStr(&offset)) { 199 OS << format("0x%8.8x: \"%s\"\n", strOffset, s); 200 strOffset = offset; 201 } 202 } 203 204 if ((DumpType == DIDT_All || DumpType == DIDT_StrDwo) && 205 !getStringDWOSection().empty()) { 206 OS << "\n.debug_str.dwo contents:\n"; 207 DataExtractor strDWOData(getStringDWOSection(), isLittleEndian(), 0); 208 offset = 0; 209 uint32_t strDWOOffset = 0; 210 while (const char *s = strDWOData.getCStr(&offset)) { 211 OS << format("0x%8.8x: \"%s\"\n", strDWOOffset, s); 212 strDWOOffset = offset; 213 } 214 } 215 216 if (DumpType == DIDT_All || DumpType == DIDT_Ranges) { 217 OS << "\n.debug_ranges contents:\n"; 218 // In fact, different compile units may have different address byte 219 // sizes, but for simplicity we just use the address byte size of the last 220 // compile unit (there is no easy and fast way to associate address range 221 // list and the compile unit it describes). 222 DataExtractor rangesData(getRangeSection(), isLittleEndian(), 223 savedAddressByteSize); 224 offset = 0; 225 DWARFDebugRangeList rangeList; 226 while (rangeList.extract(rangesData, &offset)) 227 rangeList.dump(OS); 228 } 229 230 if (DumpType == DIDT_All || DumpType == DIDT_Pubnames) 231 dumpPubSection(OS, "debug_pubnames", getPubNamesSection(), 232 isLittleEndian(), false); 233 234 if (DumpType == DIDT_All || DumpType == DIDT_Pubtypes) 235 dumpPubSection(OS, "debug_pubtypes", getPubTypesSection(), 236 isLittleEndian(), false); 237 238 if (DumpType == DIDT_All || DumpType == DIDT_GnuPubnames) 239 dumpPubSection(OS, "debug_gnu_pubnames", getGnuPubNamesSection(), 240 isLittleEndian(), true /* GnuStyle */); 241 242 if (DumpType == DIDT_All || DumpType == DIDT_GnuPubtypes) 243 dumpPubSection(OS, "debug_gnu_pubtypes", getGnuPubTypesSection(), 244 isLittleEndian(), true /* GnuStyle */); 245 246 if ((DumpType == DIDT_All || DumpType == DIDT_StrOffsetsDwo) && 247 !getStringOffsetDWOSection().empty()) { 248 OS << "\n.debug_str_offsets.dwo contents:\n"; 249 DataExtractor strOffsetExt(getStringOffsetDWOSection(), isLittleEndian(), 250 0); 251 offset = 0; 252 uint64_t size = getStringOffsetDWOSection().size(); 253 while (offset < size) { 254 OS << format("0x%8.8x: ", offset); 255 OS << format("%8.8x\n", strOffsetExt.getU32(&offset)); 256 } 257 } 258 259 if (DumpType == DIDT_All || DumpType == DIDT_AppleNames) 260 dumpAccelSection(OS, "apple_names", getAppleNamesSection(), 261 getStringSection(), isLittleEndian()); 262 263 if (DumpType == DIDT_All || DumpType == DIDT_AppleTypes) 264 dumpAccelSection(OS, "apple_types", getAppleTypesSection(), 265 getStringSection(), isLittleEndian()); 266 267 if (DumpType == DIDT_All || DumpType == DIDT_AppleNamespaces) 268 dumpAccelSection(OS, "apple_namespaces", getAppleNamespacesSection(), 269 getStringSection(), isLittleEndian()); 270 271 if (DumpType == DIDT_All || DumpType == DIDT_AppleObjC) 272 dumpAccelSection(OS, "apple_objc", getAppleObjCSection(), 273 getStringSection(), isLittleEndian()); 274 } 275 276 const DWARFUnitIndex &DWARFContext::getCUIndex() { 277 if (CUIndex) 278 return *CUIndex; 279 280 DataExtractor CUIndexData(getCUIndexSection(), isLittleEndian(), 0); 281 282 CUIndex = llvm::make_unique<DWARFUnitIndex>(DW_SECT_INFO); 283 CUIndex->parse(CUIndexData); 284 return *CUIndex; 285 } 286 287 const DWARFUnitIndex &DWARFContext::getTUIndex() { 288 if (TUIndex) 289 return *TUIndex; 290 291 DataExtractor TUIndexData(getTUIndexSection(), isLittleEndian(), 0); 292 293 TUIndex = llvm::make_unique<DWARFUnitIndex>(DW_SECT_TYPES); 294 TUIndex->parse(TUIndexData); 295 return *TUIndex; 296 } 297 298 const DWARFDebugAbbrev *DWARFContext::getDebugAbbrev() { 299 if (Abbrev) 300 return Abbrev.get(); 301 302 DataExtractor abbrData(getAbbrevSection(), isLittleEndian(), 0); 303 304 Abbrev.reset(new DWARFDebugAbbrev()); 305 Abbrev->extract(abbrData); 306 return Abbrev.get(); 307 } 308 309 const DWARFDebugAbbrev *DWARFContext::getDebugAbbrevDWO() { 310 if (AbbrevDWO) 311 return AbbrevDWO.get(); 312 313 DataExtractor abbrData(getAbbrevDWOSection(), isLittleEndian(), 0); 314 AbbrevDWO.reset(new DWARFDebugAbbrev()); 315 AbbrevDWO->extract(abbrData); 316 return AbbrevDWO.get(); 317 } 318 319 const DWARFDebugLoc *DWARFContext::getDebugLoc() { 320 if (Loc) 321 return Loc.get(); 322 323 DataExtractor LocData(getLocSection().Data, isLittleEndian(), 0); 324 Loc.reset(new DWARFDebugLoc(getLocSection().Relocs)); 325 // assume all compile units have the same address byte size 326 if (getNumCompileUnits()) 327 Loc->parse(LocData, getCompileUnitAtIndex(0)->getAddressByteSize()); 328 return Loc.get(); 329 } 330 331 const DWARFDebugLocDWO *DWARFContext::getDebugLocDWO() { 332 if (LocDWO) 333 return LocDWO.get(); 334 335 DataExtractor LocData(getLocDWOSection().Data, isLittleEndian(), 0); 336 LocDWO.reset(new DWARFDebugLocDWO()); 337 LocDWO->parse(LocData); 338 return LocDWO.get(); 339 } 340 341 const DWARFDebugAranges *DWARFContext::getDebugAranges() { 342 if (Aranges) 343 return Aranges.get(); 344 345 Aranges.reset(new DWARFDebugAranges()); 346 Aranges->generate(this); 347 return Aranges.get(); 348 } 349 350 const DWARFDebugFrame *DWARFContext::getDebugFrame() { 351 if (DebugFrame) 352 return DebugFrame.get(); 353 354 // There's a "bug" in the DWARFv3 standard with respect to the target address 355 // size within debug frame sections. While DWARF is supposed to be independent 356 // of its container, FDEs have fields with size being "target address size", 357 // which isn't specified in DWARF in general. It's only specified for CUs, but 358 // .eh_frame can appear without a .debug_info section. Follow the example of 359 // other tools (libdwarf) and extract this from the container (ObjectFile 360 // provides this information). This problem is fixed in DWARFv4 361 // See this dwarf-discuss discussion for more details: 362 // http://lists.dwarfstd.org/htdig.cgi/dwarf-discuss-dwarfstd.org/2011-December/001173.html 363 DataExtractor debugFrameData(getDebugFrameSection(), isLittleEndian(), 364 getAddressSize()); 365 DebugFrame.reset(new DWARFDebugFrame(false /* IsEH */)); 366 DebugFrame->parse(debugFrameData); 367 return DebugFrame.get(); 368 } 369 370 const DWARFDebugFrame *DWARFContext::getEHFrame() { 371 if (EHFrame) 372 return EHFrame.get(); 373 374 DataExtractor debugFrameData(getEHFrameSection(), isLittleEndian(), 375 getAddressSize()); 376 DebugFrame.reset(new DWARFDebugFrame(true /* IsEH */)); 377 DebugFrame->parse(debugFrameData); 378 return DebugFrame.get(); 379 } 380 381 const DWARFDebugMacro *DWARFContext::getDebugMacro() { 382 if (Macro) 383 return Macro.get(); 384 385 DataExtractor MacinfoData(getMacinfoSection(), isLittleEndian(), 0); 386 Macro.reset(new DWARFDebugMacro()); 387 Macro->parse(MacinfoData); 388 return Macro.get(); 389 } 390 391 const DWARFLineTable * 392 DWARFContext::getLineTableForUnit(DWARFUnit *U) { 393 if (!Line) 394 Line.reset(new DWARFDebugLine(&getLineSection().Relocs)); 395 396 const auto *UnitDIE = U->getUnitDIE(); 397 if (UnitDIE == nullptr) 398 return nullptr; 399 400 unsigned stmtOffset = 401 UnitDIE->getAttributeValueAsSectionOffset(U, DW_AT_stmt_list, -1U); 402 if (stmtOffset == -1U) 403 return nullptr; // No line table for this compile unit. 404 405 stmtOffset += U->getLineTableOffset(); 406 // See if the line table is cached. 407 if (const DWARFLineTable *lt = Line->getLineTable(stmtOffset)) 408 return lt; 409 410 // We have to parse it first. 411 DataExtractor lineData(U->getLineSection(), isLittleEndian(), 412 U->getAddressByteSize()); 413 return Line->getOrParseLineTable(lineData, stmtOffset); 414 } 415 416 void DWARFContext::parseCompileUnits() { 417 CUs.parse(*this, getInfoSection()); 418 } 419 420 void DWARFContext::parseTypeUnits() { 421 if (!TUs.empty()) 422 return; 423 for (const auto &I : getTypesSections()) { 424 TUs.emplace_back(); 425 TUs.back().parse(*this, I.second); 426 } 427 } 428 429 void DWARFContext::parseDWOCompileUnits() { 430 DWOCUs.parseDWO(*this, getInfoDWOSection()); 431 } 432 433 void DWARFContext::parseDWOTypeUnits() { 434 if (!DWOTUs.empty()) 435 return; 436 for (const auto &I : getTypesDWOSections()) { 437 DWOTUs.emplace_back(); 438 DWOTUs.back().parseDWO(*this, I.second); 439 } 440 } 441 442 DWARFCompileUnit *DWARFContext::getCompileUnitForOffset(uint32_t Offset) { 443 parseCompileUnits(); 444 return CUs.getUnitForOffset(Offset); 445 } 446 447 DWARFCompileUnit *DWARFContext::getCompileUnitForAddress(uint64_t Address) { 448 // First, get the offset of the compile unit. 449 uint32_t CUOffset = getDebugAranges()->findAddress(Address); 450 // Retrieve the compile unit. 451 return getCompileUnitForOffset(CUOffset); 452 } 453 454 static bool getFunctionNameForAddress(DWARFCompileUnit *CU, uint64_t Address, 455 FunctionNameKind Kind, 456 std::string &FunctionName) { 457 if (Kind == FunctionNameKind::None) 458 return false; 459 // The address may correspond to instruction in some inlined function, 460 // so we have to build the chain of inlined functions and take the 461 // name of the topmost function in it. 462 const DWARFDebugInfoEntryInlinedChain &InlinedChain = 463 CU->getInlinedChainForAddress(Address); 464 if (InlinedChain.DIEs.size() == 0) 465 return false; 466 const DWARFDebugInfoEntryMinimal &TopFunctionDIE = InlinedChain.DIEs[0]; 467 if (const char *Name = 468 TopFunctionDIE.getSubroutineName(InlinedChain.U, Kind)) { 469 FunctionName = Name; 470 return true; 471 } 472 return false; 473 } 474 475 DILineInfo DWARFContext::getLineInfoForAddress(uint64_t Address, 476 DILineInfoSpecifier Spec) { 477 DILineInfo Result; 478 479 DWARFCompileUnit *CU = getCompileUnitForAddress(Address); 480 if (!CU) 481 return Result; 482 getFunctionNameForAddress(CU, Address, Spec.FNKind, Result.FunctionName); 483 if (Spec.FLIKind != FileLineInfoKind::None) { 484 if (const DWARFLineTable *LineTable = getLineTableForUnit(CU)) 485 LineTable->getFileLineInfoForAddress(Address, CU->getCompilationDir(), 486 Spec.FLIKind, Result); 487 } 488 return Result; 489 } 490 491 DILineInfoTable 492 DWARFContext::getLineInfoForAddressRange(uint64_t Address, uint64_t Size, 493 DILineInfoSpecifier Spec) { 494 DILineInfoTable Lines; 495 DWARFCompileUnit *CU = getCompileUnitForAddress(Address); 496 if (!CU) 497 return Lines; 498 499 std::string FunctionName = "<invalid>"; 500 getFunctionNameForAddress(CU, Address, Spec.FNKind, FunctionName); 501 502 // If the Specifier says we don't need FileLineInfo, just 503 // return the top-most function at the starting address. 504 if (Spec.FLIKind == FileLineInfoKind::None) { 505 DILineInfo Result; 506 Result.FunctionName = FunctionName; 507 Lines.push_back(std::make_pair(Address, Result)); 508 return Lines; 509 } 510 511 const DWARFLineTable *LineTable = getLineTableForUnit(CU); 512 513 // Get the index of row we're looking for in the line table. 514 std::vector<uint32_t> RowVector; 515 if (!LineTable->lookupAddressRange(Address, Size, RowVector)) 516 return Lines; 517 518 for (uint32_t RowIndex : RowVector) { 519 // Take file number and line/column from the row. 520 const DWARFDebugLine::Row &Row = LineTable->Rows[RowIndex]; 521 DILineInfo Result; 522 LineTable->getFileNameByIndex(Row.File, CU->getCompilationDir(), 523 Spec.FLIKind, Result.FileName); 524 Result.FunctionName = FunctionName; 525 Result.Line = Row.Line; 526 Result.Column = Row.Column; 527 Lines.push_back(std::make_pair(Row.Address, Result)); 528 } 529 530 return Lines; 531 } 532 533 DIInliningInfo 534 DWARFContext::getInliningInfoForAddress(uint64_t Address, 535 DILineInfoSpecifier Spec) { 536 DIInliningInfo InliningInfo; 537 538 DWARFCompileUnit *CU = getCompileUnitForAddress(Address); 539 if (!CU) 540 return InliningInfo; 541 542 const DWARFLineTable *LineTable = nullptr; 543 const DWARFDebugInfoEntryInlinedChain &InlinedChain = 544 CU->getInlinedChainForAddress(Address); 545 if (InlinedChain.DIEs.size() == 0) { 546 // If there is no DIE for address (e.g. it is in unavailable .dwo file), 547 // try to at least get file/line info from symbol table. 548 if (Spec.FLIKind != FileLineInfoKind::None) { 549 DILineInfo Frame; 550 LineTable = getLineTableForUnit(CU); 551 if (LineTable && 552 LineTable->getFileLineInfoForAddress(Address, CU->getCompilationDir(), 553 Spec.FLIKind, Frame)) 554 InliningInfo.addFrame(Frame); 555 } 556 return InliningInfo; 557 } 558 559 uint32_t CallFile = 0, CallLine = 0, CallColumn = 0; 560 for (uint32_t i = 0, n = InlinedChain.DIEs.size(); i != n; i++) { 561 const DWARFDebugInfoEntryMinimal &FunctionDIE = InlinedChain.DIEs[i]; 562 DILineInfo Frame; 563 // Get function name if necessary. 564 if (const char *Name = 565 FunctionDIE.getSubroutineName(InlinedChain.U, Spec.FNKind)) 566 Frame.FunctionName = Name; 567 if (Spec.FLIKind != FileLineInfoKind::None) { 568 if (i == 0) { 569 // For the topmost frame, initialize the line table of this 570 // compile unit and fetch file/line info from it. 571 LineTable = getLineTableForUnit(CU); 572 // For the topmost routine, get file/line info from line table. 573 if (LineTable) 574 LineTable->getFileLineInfoForAddress(Address, CU->getCompilationDir(), 575 Spec.FLIKind, Frame); 576 } else { 577 // Otherwise, use call file, call line and call column from 578 // previous DIE in inlined chain. 579 if (LineTable) 580 LineTable->getFileNameByIndex(CallFile, CU->getCompilationDir(), 581 Spec.FLIKind, Frame.FileName); 582 Frame.Line = CallLine; 583 Frame.Column = CallColumn; 584 } 585 // Get call file/line/column of a current DIE. 586 if (i + 1 < n) { 587 FunctionDIE.getCallerFrame(InlinedChain.U, CallFile, CallLine, 588 CallColumn); 589 } 590 } 591 InliningInfo.addFrame(Frame); 592 } 593 return InliningInfo; 594 } 595 596 static bool consumeCompressedGnuHeader(StringRef &data, 597 uint64_t &OriginalSize) { 598 // Consume "ZLIB" prefix. 599 if (!data.startswith("ZLIB")) 600 return false; 601 data = data.substr(4); 602 // Consume uncompressed section size (big-endian 8 bytes). 603 DataExtractor extractor(data, false, 8); 604 uint32_t Offset = 0; 605 OriginalSize = extractor.getU64(&Offset); 606 if (Offset == 0) 607 return false; 608 data = data.substr(Offset); 609 return true; 610 } 611 612 static bool consumeCompressedZLibHeader(StringRef &Data, uint64_t &OriginalSize, 613 bool IsLE, bool Is64Bit) { 614 using namespace ELF; 615 uint64_t HdrSize = Is64Bit ? sizeof(Elf64_Chdr) : sizeof(Elf32_Chdr); 616 if (Data.size() < HdrSize) 617 return false; 618 619 DataExtractor Extractor(Data, IsLE, 0); 620 uint32_t Offset = 0; 621 if (Extractor.getUnsigned(&Offset, Is64Bit ? sizeof(Elf64_Word) 622 : sizeof(Elf32_Word)) != 623 ELFCOMPRESS_ZLIB) 624 return false; 625 626 // Skip Elf64_Chdr::ch_reserved field. 627 if (Is64Bit) 628 Offset += sizeof(Elf64_Word); 629 630 OriginalSize = Extractor.getUnsigned(&Offset, Is64Bit ? sizeof(Elf64_Xword) 631 : sizeof(Elf32_Word)); 632 Data = Data.substr(HdrSize); 633 return true; 634 } 635 636 static bool tryDecompress(StringRef &Name, StringRef &Data, 637 SmallString<32> &Out, bool ZLibStyle, bool IsLE, 638 bool Is64Bit) { 639 if (!zlib::isAvailable()) 640 return false; 641 642 uint64_t OriginalSize; 643 bool Result = 644 ZLibStyle ? consumeCompressedZLibHeader(Data, OriginalSize, IsLE, Is64Bit) 645 : consumeCompressedGnuHeader(Data, OriginalSize); 646 647 if (!Result || zlib::uncompress(Data, Out, OriginalSize) != zlib::StatusOK) 648 return false; 649 650 // gnu-style names are started from "z", consume that. 651 if (!ZLibStyle) 652 Name = Name.substr(1); 653 return true; 654 } 655 656 DWARFContextInMemory::DWARFContextInMemory(const object::ObjectFile &Obj, 657 const LoadedObjectInfo *L) 658 : IsLittleEndian(Obj.isLittleEndian()), 659 AddressSize(Obj.getBytesInAddress()) { 660 for (const SectionRef &Section : Obj.sections()) { 661 StringRef name; 662 Section.getName(name); 663 // Skip BSS and Virtual sections, they aren't interesting. 664 bool IsBSS = Section.isBSS(); 665 if (IsBSS) 666 continue; 667 bool IsVirtual = Section.isVirtual(); 668 if (IsVirtual) 669 continue; 670 StringRef data; 671 672 section_iterator RelocatedSection = Section.getRelocatedSection(); 673 // Try to obtain an already relocated version of this section. 674 // Else use the unrelocated section from the object file. We'll have to 675 // apply relocations ourselves later. 676 if (!L || !L->getLoadedSectionContents(*RelocatedSection,data)) 677 Section.getContents(data); 678 679 name = name.substr(name.find_first_not_of("._")); // Skip . and _ prefixes. 680 681 bool ZLibStyleCompressed = Section.isCompressed(); 682 if (ZLibStyleCompressed || name.startswith("zdebug_")) { 683 SmallString<32> Out; 684 if (!tryDecompress(name, data, Out, ZLibStyleCompressed, IsLittleEndian, 685 AddressSize == 8)) 686 continue; 687 UncompressedSections.emplace_back(std::move(Out)); 688 data = UncompressedSections.back(); 689 } 690 691 StringRef *SectionData = 692 StringSwitch<StringRef *>(name) 693 .Case("debug_info", &InfoSection.Data) 694 .Case("debug_abbrev", &AbbrevSection) 695 .Case("debug_loc", &LocSection.Data) 696 .Case("debug_line", &LineSection.Data) 697 .Case("debug_aranges", &ARangeSection) 698 .Case("debug_frame", &DebugFrameSection) 699 .Case("eh_frame", &EHFrameSection) 700 .Case("debug_str", &StringSection) 701 .Case("debug_ranges", &RangeSection) 702 .Case("debug_macinfo", &MacinfoSection) 703 .Case("debug_pubnames", &PubNamesSection) 704 .Case("debug_pubtypes", &PubTypesSection) 705 .Case("debug_gnu_pubnames", &GnuPubNamesSection) 706 .Case("debug_gnu_pubtypes", &GnuPubTypesSection) 707 .Case("debug_info.dwo", &InfoDWOSection.Data) 708 .Case("debug_abbrev.dwo", &AbbrevDWOSection) 709 .Case("debug_loc.dwo", &LocDWOSection.Data) 710 .Case("debug_line.dwo", &LineDWOSection.Data) 711 .Case("debug_str.dwo", &StringDWOSection) 712 .Case("debug_str_offsets.dwo", &StringOffsetDWOSection) 713 .Case("debug_addr", &AddrSection) 714 .Case("apple_names", &AppleNamesSection.Data) 715 .Case("apple_types", &AppleTypesSection.Data) 716 .Case("apple_namespaces", &AppleNamespacesSection.Data) 717 .Case("apple_namespac", &AppleNamespacesSection.Data) 718 .Case("apple_objc", &AppleObjCSection.Data) 719 .Case("debug_cu_index", &CUIndexSection) 720 .Case("debug_tu_index", &TUIndexSection) 721 // Any more debug info sections go here. 722 .Default(nullptr); 723 if (SectionData) { 724 *SectionData = data; 725 if (name == "debug_ranges") { 726 // FIXME: Use the other dwo range section when we emit it. 727 RangeDWOSection = data; 728 } 729 } else if (name == "debug_types") { 730 // Find debug_types data by section rather than name as there are 731 // multiple, comdat grouped, debug_types sections. 732 TypesSections[Section].Data = data; 733 } else if (name == "debug_types.dwo") { 734 TypesDWOSections[Section].Data = data; 735 } 736 737 if (RelocatedSection == Obj.section_end()) 738 continue; 739 740 StringRef RelSecName; 741 StringRef RelSecData; 742 RelocatedSection->getName(RelSecName); 743 744 // If the section we're relocating was relocated already by the JIT, 745 // then we used the relocated version above, so we do not need to process 746 // relocations for it now. 747 if (L && L->getLoadedSectionContents(*RelocatedSection,RelSecData)) 748 continue; 749 750 // In Mach-o files, the relocations do not need to be applied if 751 // there is no load offset to apply. The value read at the 752 // relocation point already factors in the section address 753 // (actually applying the relocations will produce wrong results 754 // as the section address will be added twice). 755 if (!L && isa<MachOObjectFile>(&Obj)) 756 continue; 757 758 RelSecName = RelSecName.substr( 759 RelSecName.find_first_not_of("._")); // Skip . and _ prefixes. 760 761 // TODO: Add support for relocations in other sections as needed. 762 // Record relocations for the debug_info and debug_line sections. 763 RelocAddrMap *Map = StringSwitch<RelocAddrMap*>(RelSecName) 764 .Case("debug_info", &InfoSection.Relocs) 765 .Case("debug_loc", &LocSection.Relocs) 766 .Case("debug_info.dwo", &InfoDWOSection.Relocs) 767 .Case("debug_line", &LineSection.Relocs) 768 .Case("apple_names", &AppleNamesSection.Relocs) 769 .Case("apple_types", &AppleTypesSection.Relocs) 770 .Case("apple_namespaces", &AppleNamespacesSection.Relocs) 771 .Case("apple_namespac", &AppleNamespacesSection.Relocs) 772 .Case("apple_objc", &AppleObjCSection.Relocs) 773 .Default(nullptr); 774 if (!Map) { 775 // Find debug_types relocs by section rather than name as there are 776 // multiple, comdat grouped, debug_types sections. 777 if (RelSecName == "debug_types") 778 Map = &TypesSections[*RelocatedSection].Relocs; 779 else if (RelSecName == "debug_types.dwo") 780 Map = &TypesDWOSections[*RelocatedSection].Relocs; 781 else 782 continue; 783 } 784 785 if (Section.relocation_begin() != Section.relocation_end()) { 786 uint64_t SectionSize = RelocatedSection->getSize(); 787 for (const RelocationRef &Reloc : Section.relocations()) { 788 uint64_t Address = Reloc.getOffset(); 789 uint64_t Type = Reloc.getType(); 790 uint64_t SymAddr = 0; 791 uint64_t SectionLoadAddress = 0; 792 object::symbol_iterator Sym = Reloc.getSymbol(); 793 object::section_iterator RSec = Obj.section_end(); 794 795 // First calculate the address of the symbol or section as it appears 796 // in the objct file 797 if (Sym != Obj.symbol_end()) { 798 Expected<uint64_t> SymAddrOrErr = Sym->getAddress(); 799 if (!SymAddrOrErr) { 800 std::string Buf; 801 raw_string_ostream OS(Buf); 802 logAllUnhandledErrors(SymAddrOrErr.takeError(), OS, ""); 803 OS.flush(); 804 errs() << "error: failed to compute symbol address: " 805 << Buf << '\n'; 806 continue; 807 } 808 SymAddr = *SymAddrOrErr; 809 // Also remember what section this symbol is in for later 810 auto SectOrErr = Sym->getSection(); 811 if (!SectOrErr) { 812 std::string Buf; 813 raw_string_ostream OS(Buf); 814 logAllUnhandledErrors(SectOrErr.takeError(), OS, ""); 815 OS.flush(); 816 errs() << "error: failed to get symbol section: " 817 << Buf << '\n'; 818 continue; 819 } 820 RSec = *SectOrErr; 821 } else if (auto *MObj = dyn_cast<MachOObjectFile>(&Obj)) { 822 // MachO also has relocations that point to sections and 823 // scattered relocations. 824 auto RelocInfo = MObj->getRelocation(Reloc.getRawDataRefImpl()); 825 if (MObj->isRelocationScattered(RelocInfo)) { 826 // FIXME: it's not clear how to correctly handle scattered 827 // relocations. 828 continue; 829 } else { 830 RSec = MObj->getRelocationSection(Reloc.getRawDataRefImpl()); 831 SymAddr = RSec->getAddress(); 832 } 833 } 834 835 // If we are given load addresses for the sections, we need to adjust: 836 // SymAddr = (Address of Symbol Or Section in File) - 837 // (Address of Section in File) + 838 // (Load Address of Section) 839 if (L != nullptr && RSec != Obj.section_end()) { 840 // RSec is now either the section being targeted or the section 841 // containing the symbol being targeted. In either case, 842 // we need to perform the same computation. 843 StringRef SecName; 844 RSec->getName(SecName); 845 // llvm::dbgs() << "Name: '" << SecName 846 // << "', RSec: " << RSec->getRawDataRefImpl() 847 // << ", Section: " << Section.getRawDataRefImpl() << "\n"; 848 SectionLoadAddress = L->getSectionLoadAddress(*RSec); 849 if (SectionLoadAddress != 0) 850 SymAddr += SectionLoadAddress - RSec->getAddress(); 851 } 852 853 object::RelocVisitor V(Obj); 854 object::RelocToApply R(V.visit(Type, Reloc, SymAddr)); 855 if (V.error()) { 856 SmallString<32> Name; 857 Reloc.getTypeName(Name); 858 errs() << "error: failed to compute relocation: " 859 << Name << "\n"; 860 continue; 861 } 862 863 if (Address + R.Width > SectionSize) { 864 errs() << "error: " << R.Width << "-byte relocation starting " 865 << Address << " bytes into section " << name << " which is " 866 << SectionSize << " bytes long.\n"; 867 continue; 868 } 869 if (R.Width > 8) { 870 errs() << "error: can't handle a relocation of more than 8 bytes at " 871 "a time.\n"; 872 continue; 873 } 874 DEBUG(dbgs() << "Writing " << format("%p", R.Value) 875 << " at " << format("%p", Address) 876 << " with width " << format("%d", R.Width) 877 << "\n"); 878 Map->insert(std::make_pair(Address, std::make_pair(R.Width, R.Value))); 879 } 880 } 881 } 882 } 883 884 void DWARFContextInMemory::anchor() { } 885
