1 //===-- llvm/CodeGen/DwarfDebug.cpp - Dwarf Debug Framework ---------------===// 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 // This file contains support for writing dwarf debug info into asm files. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #define DEBUG_TYPE "dwarfdebug" 15 #include "DwarfDebug.h" 16 #include "DIE.h" 17 #include "DIEHash.h" 18 #include "DwarfAccelTable.h" 19 #include "DwarfCompileUnit.h" 20 #include "llvm/ADT/STLExtras.h" 21 #include "llvm/ADT/Statistic.h" 22 #include "llvm/ADT/StringExtras.h" 23 #include "llvm/ADT/Triple.h" 24 #include "llvm/CodeGen/MachineFunction.h" 25 #include "llvm/CodeGen/MachineModuleInfo.h" 26 #include "llvm/DIBuilder.h" 27 #include "llvm/DebugInfo.h" 28 #include "llvm/IR/Constants.h" 29 #include "llvm/IR/DataLayout.h" 30 #include "llvm/IR/Instructions.h" 31 #include "llvm/IR/Module.h" 32 #include "llvm/MC/MCAsmInfo.h" 33 #include "llvm/MC/MCSection.h" 34 #include "llvm/MC/MCStreamer.h" 35 #include "llvm/MC/MCSymbol.h" 36 #include "llvm/Support/CommandLine.h" 37 #include "llvm/Support/Debug.h" 38 #include "llvm/Support/Dwarf.h" 39 #include "llvm/Support/ErrorHandling.h" 40 #include "llvm/Support/FormattedStream.h" 41 #include "llvm/Support/MD5.h" 42 #include "llvm/Support/Path.h" 43 #include "llvm/Support/Timer.h" 44 #include "llvm/Support/ValueHandle.h" 45 #include "llvm/Target/TargetFrameLowering.h" 46 #include "llvm/Target/TargetLoweringObjectFile.h" 47 #include "llvm/Target/TargetMachine.h" 48 #include "llvm/Target/TargetOptions.h" 49 #include "llvm/Target/TargetRegisterInfo.h" 50 using namespace llvm; 51 52 static cl::opt<bool> 53 DisableDebugInfoPrinting("disable-debug-info-print", cl::Hidden, 54 cl::desc("Disable debug info printing")); 55 56 static cl::opt<bool> UnknownLocations( 57 "use-unknown-locations", cl::Hidden, 58 cl::desc("Make an absence of debug location information explicit."), 59 cl::init(false)); 60 61 static cl::opt<bool> 62 GenerateODRHash("generate-odr-hash", cl::Hidden, 63 cl::desc("Add an ODR hash to external type DIEs."), 64 cl::init(false)); 65 66 static cl::opt<bool> 67 GenerateCUHash("generate-cu-hash", cl::Hidden, 68 cl::desc("Add the CU hash as the dwo_id."), 69 cl::init(false)); 70 71 static cl::opt<bool> 72 GenerateGnuPubSections("generate-gnu-dwarf-pub-sections", cl::Hidden, 73 cl::desc("Generate GNU-style pubnames and pubtypes"), 74 cl::init(false)); 75 76 namespace { 77 enum DefaultOnOff { 78 Default, 79 Enable, 80 Disable 81 }; 82 } 83 84 static cl::opt<DefaultOnOff> 85 DwarfAccelTables("dwarf-accel-tables", cl::Hidden, 86 cl::desc("Output prototype dwarf accelerator tables."), 87 cl::values(clEnumVal(Default, "Default for platform"), 88 clEnumVal(Enable, "Enabled"), 89 clEnumVal(Disable, "Disabled"), clEnumValEnd), 90 cl::init(Default)); 91 92 static cl::opt<DefaultOnOff> 93 SplitDwarf("split-dwarf", cl::Hidden, 94 cl::desc("Output prototype dwarf split debug info."), 95 cl::values(clEnumVal(Default, "Default for platform"), 96 clEnumVal(Enable, "Enabled"), 97 clEnumVal(Disable, "Disabled"), clEnumValEnd), 98 cl::init(Default)); 99 100 static cl::opt<DefaultOnOff> 101 DwarfPubSections("generate-dwarf-pub-sections", cl::Hidden, 102 cl::desc("Generate DWARF pubnames and pubtypes sections"), 103 cl::values(clEnumVal(Default, "Default for platform"), 104 clEnumVal(Enable, "Enabled"), 105 clEnumVal(Disable, "Disabled"), clEnumValEnd), 106 cl::init(Default)); 107 108 static const char *const DWARFGroupName = "DWARF Emission"; 109 static const char *const DbgTimerName = "DWARF Debug Writer"; 110 111 //===----------------------------------------------------------------------===// 112 113 // Configuration values for initial hash set sizes (log2). 114 // 115 static const unsigned InitAbbreviationsSetSize = 9; // log2(512) 116 117 namespace llvm { 118 119 /// resolve - Look in the DwarfDebug map for the MDNode that 120 /// corresponds to the reference. 121 template <typename T> 122 T DbgVariable::resolve(DIRef<T> Ref) const { 123 return DD->resolve(Ref); 124 } 125 126 DIType DbgVariable::getType() const { 127 DIType Ty = Var.getType(); 128 // FIXME: isBlockByrefVariable should be reformulated in terms of complex 129 // addresses instead. 130 if (Var.isBlockByrefVariable()) { 131 /* Byref variables, in Blocks, are declared by the programmer as 132 "SomeType VarName;", but the compiler creates a 133 __Block_byref_x_VarName struct, and gives the variable VarName 134 either the struct, or a pointer to the struct, as its type. This 135 is necessary for various behind-the-scenes things the compiler 136 needs to do with by-reference variables in blocks. 137 138 However, as far as the original *programmer* is concerned, the 139 variable should still have type 'SomeType', as originally declared. 140 141 The following function dives into the __Block_byref_x_VarName 142 struct to find the original type of the variable. This will be 143 passed back to the code generating the type for the Debug 144 Information Entry for the variable 'VarName'. 'VarName' will then 145 have the original type 'SomeType' in its debug information. 146 147 The original type 'SomeType' will be the type of the field named 148 'VarName' inside the __Block_byref_x_VarName struct. 149 150 NOTE: In order for this to not completely fail on the debugger 151 side, the Debug Information Entry for the variable VarName needs to 152 have a DW_AT_location that tells the debugger how to unwind through 153 the pointers and __Block_byref_x_VarName struct to find the actual 154 value of the variable. The function addBlockByrefType does this. */ 155 DIType subType = Ty; 156 uint16_t tag = Ty.getTag(); 157 158 if (tag == dwarf::DW_TAG_pointer_type) 159 subType = resolve(DIDerivedType(Ty).getTypeDerivedFrom()); 160 161 DIArray Elements = DICompositeType(subType).getTypeArray(); 162 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) { 163 DIDerivedType DT(Elements.getElement(i)); 164 if (getName() == DT.getName()) 165 return (resolve(DT.getTypeDerivedFrom())); 166 } 167 } 168 return Ty; 169 } 170 171 } // end llvm namespace 172 173 /// Return Dwarf Version by checking module flags. 174 static unsigned getDwarfVersionFromModule(const Module *M) { 175 Value *Val = M->getModuleFlag("Dwarf Version"); 176 if (!Val) 177 return dwarf::DWARF_VERSION; 178 return cast<ConstantInt>(Val)->getZExtValue(); 179 } 180 181 DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M) 182 : Asm(A), MMI(Asm->MMI), FirstCU(0), 183 AbbreviationsSet(InitAbbreviationsSetSize), 184 SourceIdMap(DIEValueAllocator), 185 PrevLabel(NULL), GlobalCUIndexCount(0), 186 InfoHolder(A, &AbbreviationsSet, Abbreviations, "info_string", 187 DIEValueAllocator), 188 SkeletonAbbrevSet(InitAbbreviationsSetSize), 189 SkeletonHolder(A, &SkeletonAbbrevSet, SkeletonAbbrevs, "skel_string", 190 DIEValueAllocator) { 191 192 DwarfInfoSectionSym = DwarfAbbrevSectionSym = 0; 193 DwarfStrSectionSym = TextSectionSym = 0; 194 DwarfDebugRangeSectionSym = DwarfDebugLocSectionSym = DwarfLineSectionSym = 0; 195 DwarfAddrSectionSym = 0; 196 DwarfAbbrevDWOSectionSym = DwarfStrDWOSectionSym = 0; 197 FunctionBeginSym = FunctionEndSym = 0; 198 199 // Turn on accelerator tables for Darwin by default, pubnames by 200 // default for non-Darwin, and handle split dwarf. 201 bool IsDarwin = Triple(A->getTargetTriple()).isOSDarwin(); 202 203 if (DwarfAccelTables == Default) 204 HasDwarfAccelTables = IsDarwin; 205 else 206 HasDwarfAccelTables = DwarfAccelTables == Enable; 207 208 if (SplitDwarf == Default) 209 HasSplitDwarf = false; 210 else 211 HasSplitDwarf = SplitDwarf == Enable; 212 213 if (DwarfPubSections == Default) 214 HasDwarfPubSections = !IsDarwin; 215 else 216 HasDwarfPubSections = DwarfPubSections == Enable; 217 218 DwarfVersion = getDwarfVersionFromModule(MMI->getModule()); 219 220 { 221 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 222 beginModule(); 223 } 224 } 225 226 // Switch to the specified MCSection and emit an assembler 227 // temporary label to it if SymbolStem is specified. 228 static MCSymbol *emitSectionSym(AsmPrinter *Asm, const MCSection *Section, 229 const char *SymbolStem = 0) { 230 Asm->OutStreamer.SwitchSection(Section); 231 if (!SymbolStem) return 0; 232 233 MCSymbol *TmpSym = Asm->GetTempSymbol(SymbolStem); 234 Asm->OutStreamer.EmitLabel(TmpSym); 235 return TmpSym; 236 } 237 238 MCSymbol *DwarfUnits::getStringPoolSym() { 239 return Asm->GetTempSymbol(StringPref); 240 } 241 242 MCSymbol *DwarfUnits::getStringPoolEntry(StringRef Str) { 243 std::pair<MCSymbol*, unsigned> &Entry = 244 StringPool.GetOrCreateValue(Str).getValue(); 245 if (Entry.first) return Entry.first; 246 247 Entry.second = NextStringPoolNumber++; 248 return Entry.first = Asm->GetTempSymbol(StringPref, Entry.second); 249 } 250 251 unsigned DwarfUnits::getStringPoolIndex(StringRef Str) { 252 std::pair<MCSymbol*, unsigned> &Entry = 253 StringPool.GetOrCreateValue(Str).getValue(); 254 if (Entry.first) return Entry.second; 255 256 Entry.second = NextStringPoolNumber++; 257 Entry.first = Asm->GetTempSymbol(StringPref, Entry.second); 258 return Entry.second; 259 } 260 261 unsigned DwarfUnits::getAddrPoolIndex(const MCSymbol *Sym) { 262 return getAddrPoolIndex(MCSymbolRefExpr::Create(Sym, Asm->OutContext)); 263 } 264 265 unsigned DwarfUnits::getAddrPoolIndex(const MCExpr *Sym) { 266 std::pair<DenseMap<const MCExpr *, unsigned>::iterator, bool> P = 267 AddressPool.insert(std::make_pair(Sym, NextAddrPoolNumber)); 268 if (P.second) 269 ++NextAddrPoolNumber; 270 return P.first->second; 271 } 272 273 // Define a unique number for the abbreviation. 274 // 275 void DwarfUnits::assignAbbrevNumber(DIEAbbrev &Abbrev) { 276 // Check the set for priors. 277 DIEAbbrev *InSet = AbbreviationsSet->GetOrInsertNode(&Abbrev); 278 279 // If it's newly added. 280 if (InSet == &Abbrev) { 281 // Add to abbreviation list. 282 Abbreviations.push_back(&Abbrev); 283 284 // Assign the vector position + 1 as its number. 285 Abbrev.setNumber(Abbreviations.size()); 286 } else { 287 // Assign existing abbreviation number. 288 Abbrev.setNumber(InSet->getNumber()); 289 } 290 } 291 292 static bool isObjCClass(StringRef Name) { 293 return Name.startswith("+") || Name.startswith("-"); 294 } 295 296 static bool hasObjCCategory(StringRef Name) { 297 if (!isObjCClass(Name)) return false; 298 299 return Name.find(") ") != StringRef::npos; 300 } 301 302 static void getObjCClassCategory(StringRef In, StringRef &Class, 303 StringRef &Category) { 304 if (!hasObjCCategory(In)) { 305 Class = In.slice(In.find('[') + 1, In.find(' ')); 306 Category = ""; 307 return; 308 } 309 310 Class = In.slice(In.find('[') + 1, In.find('(')); 311 Category = In.slice(In.find('[') + 1, In.find(' ')); 312 return; 313 } 314 315 static StringRef getObjCMethodName(StringRef In) { 316 return In.slice(In.find(' ') + 1, In.find(']')); 317 } 318 319 // Helper for sorting sections into a stable output order. 320 static bool SectionSort(const MCSection *A, const MCSection *B) { 321 std::string LA = (A ? A->getLabelBeginName() : ""); 322 std::string LB = (B ? B->getLabelBeginName() : ""); 323 return LA < LB; 324 } 325 326 // Add the various names to the Dwarf accelerator table names. 327 // TODO: Determine whether or not we should add names for programs 328 // that do not have a DW_AT_name or DW_AT_linkage_name field - this 329 // is only slightly different than the lookup of non-standard ObjC names. 330 static void addSubprogramNames(CompileUnit *TheCU, DISubprogram SP, 331 DIE* Die) { 332 if (!SP.isDefinition()) return; 333 TheCU->addAccelName(SP.getName(), Die); 334 335 // If the linkage name is different than the name, go ahead and output 336 // that as well into the name table. 337 if (SP.getLinkageName() != "" && SP.getName() != SP.getLinkageName()) 338 TheCU->addAccelName(SP.getLinkageName(), Die); 339 340 // If this is an Objective-C selector name add it to the ObjC accelerator 341 // too. 342 if (isObjCClass(SP.getName())) { 343 StringRef Class, Category; 344 getObjCClassCategory(SP.getName(), Class, Category); 345 TheCU->addAccelObjC(Class, Die); 346 if (Category != "") 347 TheCU->addAccelObjC(Category, Die); 348 // Also add the base method name to the name table. 349 TheCU->addAccelName(getObjCMethodName(SP.getName()), Die); 350 } 351 } 352 353 /// isSubprogramContext - Return true if Context is either a subprogram 354 /// or another context nested inside a subprogram. 355 bool DwarfDebug::isSubprogramContext(const MDNode *Context) { 356 if (!Context) 357 return false; 358 DIDescriptor D(Context); 359 if (D.isSubprogram()) 360 return true; 361 if (D.isType()) 362 return isSubprogramContext(resolve(DIType(Context).getContext())); 363 return false; 364 } 365 366 // Find DIE for the given subprogram and attach appropriate DW_AT_low_pc 367 // and DW_AT_high_pc attributes. If there are global variables in this 368 // scope then create and insert DIEs for these variables. 369 DIE *DwarfDebug::updateSubprogramScopeDIE(CompileUnit *SPCU, DISubprogram SP) { 370 DIE *SPDie = SPCU->getDIE(SP); 371 372 assert(SPDie && "Unable to find subprogram DIE!"); 373 374 // If we're updating an abstract DIE, then we will be adding the children and 375 // object pointer later on. But what we don't want to do is process the 376 // concrete DIE twice. 377 if (DIE *AbsSPDIE = AbstractSPDies.lookup(SP)) { 378 // Pick up abstract subprogram DIE. 379 SPDie = SPCU->createAndAddDIE(dwarf::DW_TAG_subprogram, *SPCU->getCUDie()); 380 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_abstract_origin, AbsSPDIE); 381 } else { 382 DISubprogram SPDecl = SP.getFunctionDeclaration(); 383 if (!SPDecl.isSubprogram()) { 384 // There is not any need to generate specification DIE for a function 385 // defined at compile unit level. If a function is defined inside another 386 // function then gdb prefers the definition at top level and but does not 387 // expect specification DIE in parent function. So avoid creating 388 // specification DIE for a function defined inside a function. 389 DIScope SPContext = resolve(SP.getContext()); 390 if (SP.isDefinition() && !SPContext.isCompileUnit() && 391 !SPContext.isFile() && 392 !isSubprogramContext(SPContext)) { 393 SPCU->addFlag(SPDie, dwarf::DW_AT_declaration); 394 395 // Add arguments. 396 DICompositeType SPTy = SP.getType(); 397 DIArray Args = SPTy.getTypeArray(); 398 uint16_t SPTag = SPTy.getTag(); 399 if (SPTag == dwarf::DW_TAG_subroutine_type) 400 for (unsigned i = 1, N = Args.getNumElements(); i < N; ++i) { 401 DIE *Arg = 402 SPCU->createAndAddDIE(dwarf::DW_TAG_formal_parameter, *SPDie); 403 DIType ATy(Args.getElement(i)); 404 SPCU->addType(Arg, ATy); 405 if (ATy.isArtificial()) 406 SPCU->addFlag(Arg, dwarf::DW_AT_artificial); 407 if (ATy.isObjectPointer()) 408 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_object_pointer, Arg); 409 } 410 DIE *SPDeclDie = SPDie; 411 SPDie = 412 SPCU->createAndAddDIE(dwarf::DW_TAG_subprogram, *SPCU->getCUDie()); 413 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_specification, SPDeclDie); 414 } 415 } 416 } 417 418 SPCU->addLabelAddress(SPDie, dwarf::DW_AT_low_pc, 419 Asm->GetTempSymbol("func_begin", 420 Asm->getFunctionNumber())); 421 SPCU->addLabelAddress(SPDie, dwarf::DW_AT_high_pc, 422 Asm->GetTempSymbol("func_end", 423 Asm->getFunctionNumber())); 424 const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo(); 425 MachineLocation Location(RI->getFrameRegister(*Asm->MF)); 426 SPCU->addAddress(SPDie, dwarf::DW_AT_frame_base, Location); 427 428 // Add name to the name table, we do this here because we're guaranteed 429 // to have concrete versions of our DW_TAG_subprogram nodes. 430 addSubprogramNames(SPCU, SP, SPDie); 431 432 return SPDie; 433 } 434 435 /// Check whether we should create a DIE for the given Scope, return true 436 /// if we don't create a DIE (the corresponding DIE is null). 437 bool DwarfDebug::isLexicalScopeDIENull(LexicalScope *Scope) { 438 if (Scope->isAbstractScope()) 439 return false; 440 441 // We don't create a DIE if there is no Range. 442 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 443 if (Ranges.empty()) 444 return true; 445 446 if (Ranges.size() > 1) 447 return false; 448 449 // We don't create a DIE if we have a single Range and the end label 450 // is null. 451 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 452 MCSymbol *End = getLabelAfterInsn(RI->second); 453 return !End; 454 } 455 456 // Construct new DW_TAG_lexical_block for this scope and attach 457 // DW_AT_low_pc/DW_AT_high_pc labels. 458 DIE *DwarfDebug::constructLexicalScopeDIE(CompileUnit *TheCU, 459 LexicalScope *Scope) { 460 if (isLexicalScopeDIENull(Scope)) 461 return 0; 462 463 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_lexical_block); 464 if (Scope->isAbstractScope()) 465 return ScopeDIE; 466 467 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 468 // If we have multiple ranges, emit them into the range section. 469 if (Ranges.size() > 1) { 470 // .debug_range section has not been laid out yet. Emit offset in 471 // .debug_range as a uint, size 4, for now. emitDIE will handle 472 // DW_AT_ranges appropriately. 473 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_ranges, dwarf::DW_FORM_data4, 474 DebugRangeSymbols.size() 475 * Asm->getDataLayout().getPointerSize()); 476 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 477 RE = Ranges.end(); RI != RE; ++RI) { 478 DebugRangeSymbols.push_back(getLabelBeforeInsn(RI->first)); 479 DebugRangeSymbols.push_back(getLabelAfterInsn(RI->second)); 480 } 481 482 // Terminate the range list. 483 DebugRangeSymbols.push_back(NULL); 484 DebugRangeSymbols.push_back(NULL); 485 return ScopeDIE; 486 } 487 488 // Construct the address range for this DIE. 489 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 490 MCSymbol *Start = getLabelBeforeInsn(RI->first); 491 MCSymbol *End = getLabelAfterInsn(RI->second); 492 assert(End && "End label should not be null!"); 493 494 assert(Start->isDefined() && "Invalid starting label for an inlined scope!"); 495 assert(End->isDefined() && "Invalid end label for an inlined scope!"); 496 497 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_low_pc, Start); 498 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_high_pc, End); 499 500 return ScopeDIE; 501 } 502 503 // This scope represents inlined body of a function. Construct DIE to 504 // represent this concrete inlined copy of the function. 505 DIE *DwarfDebug::constructInlinedScopeDIE(CompileUnit *TheCU, 506 LexicalScope *Scope) { 507 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 508 assert(Ranges.empty() == false && 509 "LexicalScope does not have instruction markers!"); 510 511 if (!Scope->getScopeNode()) 512 return NULL; 513 DIScope DS(Scope->getScopeNode()); 514 DISubprogram InlinedSP = getDISubprogram(DS); 515 DIE *OriginDIE = TheCU->getDIE(InlinedSP); 516 if (!OriginDIE) { 517 DEBUG(dbgs() << "Unable to find original DIE for an inlined subprogram."); 518 return NULL; 519 } 520 521 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_inlined_subroutine); 522 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_abstract_origin, OriginDIE); 523 524 if (Ranges.size() > 1) { 525 // .debug_range section has not been laid out yet. Emit offset in 526 // .debug_range as a uint, size 4, for now. emitDIE will handle 527 // DW_AT_ranges appropriately. 528 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_ranges, dwarf::DW_FORM_data4, 529 DebugRangeSymbols.size() 530 * Asm->getDataLayout().getPointerSize()); 531 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 532 RE = Ranges.end(); RI != RE; ++RI) { 533 DebugRangeSymbols.push_back(getLabelBeforeInsn(RI->first)); 534 DebugRangeSymbols.push_back(getLabelAfterInsn(RI->second)); 535 } 536 DebugRangeSymbols.push_back(NULL); 537 DebugRangeSymbols.push_back(NULL); 538 } else { 539 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 540 MCSymbol *StartLabel = getLabelBeforeInsn(RI->first); 541 MCSymbol *EndLabel = getLabelAfterInsn(RI->second); 542 543 if (StartLabel == 0 || EndLabel == 0) 544 llvm_unreachable("Unexpected Start and End labels for an inlined scope!"); 545 546 assert(StartLabel->isDefined() && 547 "Invalid starting label for an inlined scope!"); 548 assert(EndLabel->isDefined() && "Invalid end label for an inlined scope!"); 549 550 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_low_pc, StartLabel); 551 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_high_pc, EndLabel); 552 } 553 554 InlinedSubprogramDIEs.insert(OriginDIE); 555 556 // Add the call site information to the DIE. 557 DILocation DL(Scope->getInlinedAt()); 558 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_file, None, 559 getOrCreateSourceID(DL.getFilename(), DL.getDirectory(), 560 TheCU->getUniqueID())); 561 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_line, None, DL.getLineNumber()); 562 563 // Add name to the name table, we do this here because we're guaranteed 564 // to have concrete versions of our DW_TAG_inlined_subprogram nodes. 565 addSubprogramNames(TheCU, InlinedSP, ScopeDIE); 566 567 return ScopeDIE; 568 } 569 570 DIE *DwarfDebug::createScopeChildrenDIE(CompileUnit *TheCU, LexicalScope *Scope, 571 SmallVectorImpl<DIE*> &Children) { 572 DIE *ObjectPointer = NULL; 573 574 // Collect arguments for current function. 575 if (LScopes.isCurrentFunctionScope(Scope)) 576 for (unsigned i = 0, N = CurrentFnArguments.size(); i < N; ++i) 577 if (DbgVariable *ArgDV = CurrentFnArguments[i]) 578 if (DIE *Arg = 579 TheCU->constructVariableDIE(*ArgDV, Scope->isAbstractScope())) { 580 Children.push_back(Arg); 581 if (ArgDV->isObjectPointer()) ObjectPointer = Arg; 582 } 583 584 // Collect lexical scope children first. 585 const SmallVectorImpl<DbgVariable *> &Variables =ScopeVariables.lookup(Scope); 586 for (unsigned i = 0, N = Variables.size(); i < N; ++i) 587 if (DIE *Variable = 588 TheCU->constructVariableDIE(*Variables[i], Scope->isAbstractScope())) { 589 Children.push_back(Variable); 590 if (Variables[i]->isObjectPointer()) ObjectPointer = Variable; 591 } 592 const SmallVectorImpl<LexicalScope *> &Scopes = Scope->getChildren(); 593 for (unsigned j = 0, M = Scopes.size(); j < M; ++j) 594 if (DIE *Nested = constructScopeDIE(TheCU, Scopes[j])) 595 Children.push_back(Nested); 596 return ObjectPointer; 597 } 598 599 // Construct a DIE for this scope. 600 DIE *DwarfDebug::constructScopeDIE(CompileUnit *TheCU, LexicalScope *Scope) { 601 if (!Scope || !Scope->getScopeNode()) 602 return NULL; 603 604 DIScope DS(Scope->getScopeNode()); 605 606 SmallVector<DIE *, 8> Children; 607 DIE *ObjectPointer = NULL; 608 bool ChildrenCreated = false; 609 610 // We try to create the scope DIE first, then the children DIEs. This will 611 // avoid creating un-used children then removing them later when we find out 612 // the scope DIE is null. 613 DIE *ScopeDIE = NULL; 614 if (Scope->getInlinedAt()) 615 ScopeDIE = constructInlinedScopeDIE(TheCU, Scope); 616 else if (DS.isSubprogram()) { 617 ProcessedSPNodes.insert(DS); 618 if (Scope->isAbstractScope()) { 619 ScopeDIE = TheCU->getDIE(DS); 620 // Note down abstract DIE. 621 if (ScopeDIE) 622 AbstractSPDies.insert(std::make_pair(DS, ScopeDIE)); 623 } else 624 ScopeDIE = updateSubprogramScopeDIE(TheCU, DISubprogram(DS)); 625 } else { 626 // Early exit when we know the scope DIE is going to be null. 627 if (isLexicalScopeDIENull(Scope)) 628 return NULL; 629 630 // We create children here when we know the scope DIE is not going to be 631 // null and the children will be added to the scope DIE. 632 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children); 633 ChildrenCreated = true; 634 635 // There is no need to emit empty lexical block DIE. 636 std::pair<ImportedEntityMap::const_iterator, 637 ImportedEntityMap::const_iterator> Range = std::equal_range( 638 ScopesWithImportedEntities.begin(), ScopesWithImportedEntities.end(), 639 std::pair<const MDNode *, const MDNode *>(DS, (const MDNode*)0), 640 less_first()); 641 if (Children.empty() && Range.first == Range.second) 642 return NULL; 643 ScopeDIE = constructLexicalScopeDIE(TheCU, Scope); 644 assert(ScopeDIE && "Scope DIE should not be null."); 645 for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second; 646 ++i) 647 constructImportedEntityDIE(TheCU, i->second, ScopeDIE); 648 } 649 650 if (!ScopeDIE) { 651 assert(Children.empty() && 652 "We create children only when the scope DIE is not null."); 653 return NULL; 654 } 655 if (!ChildrenCreated) 656 // We create children when the scope DIE is not null. 657 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children); 658 659 // Add children 660 for (SmallVectorImpl<DIE *>::iterator I = Children.begin(), 661 E = Children.end(); I != E; ++I) 662 ScopeDIE->addChild(*I); 663 664 if (DS.isSubprogram() && ObjectPointer != NULL) 665 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, ObjectPointer); 666 667 if (DS.isSubprogram()) 668 TheCU->addPubTypes(DISubprogram(DS)); 669 670 return ScopeDIE; 671 } 672 673 // Look up the source id with the given directory and source file names. 674 // If none currently exists, create a new id and insert it in the 675 // SourceIds map. This can update DirectoryNames and SourceFileNames maps 676 // as well. 677 unsigned DwarfDebug::getOrCreateSourceID(StringRef FileName, 678 StringRef DirName, unsigned CUID) { 679 // If we use .loc in assembly, we can't separate .file entries according to 680 // compile units. Thus all files will belong to the default compile unit. 681 682 // FIXME: add a better feature test than hasRawTextSupport. Even better, 683 // extend .file to support this. 684 if (Asm->TM.hasMCUseLoc() && Asm->OutStreamer.hasRawTextSupport()) 685 CUID = 0; 686 687 // If FE did not provide a file name, then assume stdin. 688 if (FileName.empty()) 689 return getOrCreateSourceID("<stdin>", StringRef(), CUID); 690 691 // TODO: this might not belong here. See if we can factor this better. 692 if (DirName == CompilationDir) 693 DirName = ""; 694 695 // FileIDCUMap stores the current ID for the given compile unit. 696 unsigned SrcId = FileIDCUMap[CUID] + 1; 697 698 // We look up the CUID/file/dir by concatenating them with a zero byte. 699 SmallString<128> NamePair; 700 NamePair += utostr(CUID); 701 NamePair += '\0'; 702 NamePair += DirName; 703 NamePair += '\0'; // Zero bytes are not allowed in paths. 704 NamePair += FileName; 705 706 StringMapEntry<unsigned> &Ent = SourceIdMap.GetOrCreateValue(NamePair, SrcId); 707 if (Ent.getValue() != SrcId) 708 return Ent.getValue(); 709 710 FileIDCUMap[CUID] = SrcId; 711 // Print out a .file directive to specify files for .loc directives. 712 Asm->OutStreamer.EmitDwarfFileDirective(SrcId, DirName, FileName, CUID); 713 714 return SrcId; 715 } 716 717 // Create new CompileUnit for the given metadata node with tag 718 // DW_TAG_compile_unit. 719 CompileUnit *DwarfDebug::constructCompileUnit(DICompileUnit DIUnit) { 720 StringRef FN = DIUnit.getFilename(); 721 CompilationDir = DIUnit.getDirectory(); 722 723 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit); 724 CompileUnit *NewCU = new CompileUnit(GlobalCUIndexCount++, Die, DIUnit, Asm, 725 this, &InfoHolder); 726 727 FileIDCUMap[NewCU->getUniqueID()] = 0; 728 // Call this to emit a .file directive if it wasn't emitted for the source 729 // file this CU comes from yet. 730 getOrCreateSourceID(FN, CompilationDir, NewCU->getUniqueID()); 731 732 NewCU->addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer()); 733 NewCU->addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2, 734 DIUnit.getLanguage()); 735 NewCU->addString(Die, dwarf::DW_AT_name, FN); 736 737 // 2.17.1 requires that we use DW_AT_low_pc for a single entry point 738 // into an entity. We're using 0 (or a NULL label) for this. For 739 // split dwarf it's in the skeleton CU so omit it here. 740 if (!useSplitDwarf()) 741 NewCU->addLabelAddress(Die, dwarf::DW_AT_low_pc, NULL); 742 743 // Define start line table label for each Compile Unit. 744 MCSymbol *LineTableStartSym = Asm->GetTempSymbol("line_table_start", 745 NewCU->getUniqueID()); 746 Asm->OutStreamer.getContext().setMCLineTableSymbol(LineTableStartSym, 747 NewCU->getUniqueID()); 748 749 // Use a single line table if we are using .loc and generating assembly. 750 bool UseTheFirstCU = 751 (Asm->TM.hasMCUseLoc() && Asm->OutStreamer.hasRawTextSupport()) || 752 (NewCU->getUniqueID() == 0); 753 754 if (!useSplitDwarf()) { 755 // DW_AT_stmt_list is a offset of line number information for this 756 // compile unit in debug_line section. For split dwarf this is 757 // left in the skeleton CU and so not included. 758 // The line table entries are not always emitted in assembly, so it 759 // is not okay to use line_table_start here. 760 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 761 NewCU->addLabel(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 762 UseTheFirstCU ? Asm->GetTempSymbol("section_line") 763 : LineTableStartSym); 764 else if (UseTheFirstCU) 765 NewCU->addUInt(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4, 0); 766 else 767 NewCU->addDelta(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4, 768 LineTableStartSym, DwarfLineSectionSym); 769 770 // If we're using split dwarf the compilation dir is going to be in the 771 // skeleton CU and so we don't need to duplicate it here. 772 if (!CompilationDir.empty()) 773 NewCU->addString(Die, dwarf::DW_AT_comp_dir, CompilationDir); 774 775 // Flags to let the linker know we have emitted new style pubnames. Only 776 // emit it here if we don't have a skeleton CU for split dwarf. 777 if (GenerateGnuPubSections) { 778 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 779 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubnames, 780 dwarf::DW_FORM_sec_offset, 781 Asm->GetTempSymbol("gnu_pubnames", 782 NewCU->getUniqueID())); 783 else 784 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_data4, 785 Asm->GetTempSymbol("gnu_pubnames", 786 NewCU->getUniqueID()), 787 DwarfGnuPubNamesSectionSym); 788 789 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 790 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubtypes, 791 dwarf::DW_FORM_sec_offset, 792 Asm->GetTempSymbol("gnu_pubtypes", 793 NewCU->getUniqueID())); 794 else 795 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_data4, 796 Asm->GetTempSymbol("gnu_pubtypes", 797 NewCU->getUniqueID()), 798 DwarfGnuPubTypesSectionSym); 799 } 800 } 801 802 if (DIUnit.isOptimized()) 803 NewCU->addFlag(Die, dwarf::DW_AT_APPLE_optimized); 804 805 StringRef Flags = DIUnit.getFlags(); 806 if (!Flags.empty()) 807 NewCU->addString(Die, dwarf::DW_AT_APPLE_flags, Flags); 808 809 if (unsigned RVer = DIUnit.getRunTimeVersion()) 810 NewCU->addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers, 811 dwarf::DW_FORM_data1, RVer); 812 813 if (!FirstCU) 814 FirstCU = NewCU; 815 816 InfoHolder.addUnit(NewCU); 817 818 CUMap.insert(std::make_pair(DIUnit, NewCU)); 819 CUDieMap.insert(std::make_pair(Die, NewCU)); 820 return NewCU; 821 } 822 823 // Construct subprogram DIE. 824 void DwarfDebug::constructSubprogramDIE(CompileUnit *TheCU, const MDNode *N) { 825 // FIXME: We should only call this routine once, however, during LTO if a 826 // program is defined in multiple CUs we could end up calling it out of 827 // beginModule as we walk the CUs. 828 829 CompileUnit *&CURef = SPMap[N]; 830 if (CURef) 831 return; 832 CURef = TheCU; 833 834 DISubprogram SP(N); 835 if (!SP.isDefinition()) 836 // This is a method declaration which will be handled while constructing 837 // class type. 838 return; 839 840 DIE *SubprogramDie = TheCU->getOrCreateSubprogramDIE(SP); 841 842 // Expose as a global name. 843 TheCU->addGlobalName(SP.getName(), SubprogramDie, resolve(SP.getContext())); 844 } 845 846 void DwarfDebug::constructImportedEntityDIE(CompileUnit *TheCU, 847 const MDNode *N) { 848 DIImportedEntity Module(N); 849 if (!Module.Verify()) 850 return; 851 if (DIE *D = TheCU->getOrCreateContextDIE(Module.getContext())) 852 constructImportedEntityDIE(TheCU, Module, D); 853 } 854 855 void DwarfDebug::constructImportedEntityDIE(CompileUnit *TheCU, const MDNode *N, 856 DIE *Context) { 857 DIImportedEntity Module(N); 858 if (!Module.Verify()) 859 return; 860 return constructImportedEntityDIE(TheCU, Module, Context); 861 } 862 863 void DwarfDebug::constructImportedEntityDIE(CompileUnit *TheCU, 864 const DIImportedEntity &Module, 865 DIE *Context) { 866 assert(Module.Verify() && 867 "Use one of the MDNode * overloads to handle invalid metadata"); 868 assert(Context && "Should always have a context for an imported_module"); 869 DIE *IMDie = new DIE(Module.getTag()); 870 TheCU->insertDIE(Module, IMDie); 871 DIE *EntityDie; 872 DIDescriptor Entity = Module.getEntity(); 873 if (Entity.isNameSpace()) 874 EntityDie = TheCU->getOrCreateNameSpace(DINameSpace(Entity)); 875 else if (Entity.isSubprogram()) 876 EntityDie = TheCU->getOrCreateSubprogramDIE(DISubprogram(Entity)); 877 else if (Entity.isType()) 878 EntityDie = TheCU->getOrCreateTypeDIE(DIType(Entity)); 879 else 880 EntityDie = TheCU->getDIE(Entity); 881 unsigned FileID = getOrCreateSourceID(Module.getContext().getFilename(), 882 Module.getContext().getDirectory(), 883 TheCU->getUniqueID()); 884 TheCU->addUInt(IMDie, dwarf::DW_AT_decl_file, None, FileID); 885 TheCU->addUInt(IMDie, dwarf::DW_AT_decl_line, None, Module.getLineNumber()); 886 TheCU->addDIEEntry(IMDie, dwarf::DW_AT_import, EntityDie); 887 StringRef Name = Module.getName(); 888 if (!Name.empty()) 889 TheCU->addString(IMDie, dwarf::DW_AT_name, Name); 890 Context->addChild(IMDie); 891 } 892 893 // Emit all Dwarf sections that should come prior to the content. Create 894 // global DIEs and emit initial debug info sections. This is invoked by 895 // the target AsmPrinter. 896 void DwarfDebug::beginModule() { 897 if (DisableDebugInfoPrinting) 898 return; 899 900 const Module *M = MMI->getModule(); 901 902 // If module has named metadata anchors then use them, otherwise scan the 903 // module using debug info finder to collect debug info. 904 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu"); 905 if (!CU_Nodes) 906 return; 907 TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes); 908 909 // Emit initial sections so we can reference labels later. 910 emitSectionLabels(); 911 912 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) { 913 DICompileUnit CUNode(CU_Nodes->getOperand(i)); 914 CompileUnit *CU = constructCompileUnit(CUNode); 915 DIArray ImportedEntities = CUNode.getImportedEntities(); 916 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i) 917 ScopesWithImportedEntities.push_back(std::make_pair( 918 DIImportedEntity(ImportedEntities.getElement(i)).getContext(), 919 ImportedEntities.getElement(i))); 920 std::sort(ScopesWithImportedEntities.begin(), 921 ScopesWithImportedEntities.end(), less_first()); 922 DIArray GVs = CUNode.getGlobalVariables(); 923 for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i) 924 CU->createGlobalVariableDIE(DIGlobalVariable(GVs.getElement(i))); 925 DIArray SPs = CUNode.getSubprograms(); 926 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) 927 constructSubprogramDIE(CU, SPs.getElement(i)); 928 DIArray EnumTypes = CUNode.getEnumTypes(); 929 for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i) 930 CU->getOrCreateTypeDIE(EnumTypes.getElement(i)); 931 DIArray RetainedTypes = CUNode.getRetainedTypes(); 932 for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i) 933 CU->getOrCreateTypeDIE(RetainedTypes.getElement(i)); 934 // Emit imported_modules last so that the relevant context is already 935 // available. 936 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i) 937 constructImportedEntityDIE(CU, ImportedEntities.getElement(i)); 938 } 939 940 // Tell MMI that we have debug info. 941 MMI->setDebugInfoAvailability(true); 942 943 // Prime section data. 944 SectionMap[Asm->getObjFileLowering().getTextSection()]; 945 } 946 947 // Attach DW_AT_inline attribute with inlined subprogram DIEs. 948 void DwarfDebug::computeInlinedDIEs() { 949 // Attach DW_AT_inline attribute with inlined subprogram DIEs. 950 for (SmallPtrSet<DIE *, 4>::iterator AI = InlinedSubprogramDIEs.begin(), 951 AE = InlinedSubprogramDIEs.end(); AI != AE; ++AI) { 952 DIE *ISP = *AI; 953 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined); 954 } 955 for (DenseMap<const MDNode *, DIE *>::iterator AI = AbstractSPDies.begin(), 956 AE = AbstractSPDies.end(); AI != AE; ++AI) { 957 DIE *ISP = AI->second; 958 if (InlinedSubprogramDIEs.count(ISP)) 959 continue; 960 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined); 961 } 962 } 963 964 // Collect info for variables that were optimized out. 965 void DwarfDebug::collectDeadVariables() { 966 const Module *M = MMI->getModule(); 967 968 if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) { 969 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) { 970 DICompileUnit TheCU(CU_Nodes->getOperand(i)); 971 DIArray Subprograms = TheCU.getSubprograms(); 972 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) { 973 DISubprogram SP(Subprograms.getElement(i)); 974 if (ProcessedSPNodes.count(SP) != 0) 975 continue; 976 if (!SP.isSubprogram()) 977 continue; 978 if (!SP.isDefinition()) 979 continue; 980 DIArray Variables = SP.getVariables(); 981 if (Variables.getNumElements() == 0) 982 continue; 983 984 // Construct subprogram DIE and add variables DIEs. 985 CompileUnit *SPCU = CUMap.lookup(TheCU); 986 assert(SPCU && "Unable to find Compile Unit!"); 987 // FIXME: See the comment in constructSubprogramDIE about duplicate 988 // subprogram DIEs. 989 constructSubprogramDIE(SPCU, SP); 990 DIE *SPDIE = SPCU->getDIE(SP); 991 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) { 992 DIVariable DV(Variables.getElement(vi)); 993 if (!DV.isVariable()) 994 continue; 995 DbgVariable NewVar(DV, NULL, this); 996 if (DIE *VariableDIE = 997 SPCU->constructVariableDIE(NewVar, false)) 998 SPDIE->addChild(VariableDIE); 999 } 1000 } 1001 } 1002 } 1003 } 1004 1005 // Type Signature [7.27] and ODR Hash code. 1006 1007 /// \brief Grabs the string in whichever attribute is passed in and returns 1008 /// a reference to it. Returns "" if the attribute doesn't exist. 1009 static StringRef getDIEStringAttr(DIE *Die, unsigned Attr) { 1010 DIEValue *V = Die->findAttribute(Attr); 1011 1012 if (DIEString *S = dyn_cast_or_null<DIEString>(V)) 1013 return S->getString(); 1014 1015 return StringRef(""); 1016 } 1017 1018 /// Return true if the current DIE is contained within an anonymous namespace. 1019 static bool isContainedInAnonNamespace(DIE *Die) { 1020 DIE *Parent = Die->getParent(); 1021 1022 while (Parent) { 1023 if (Parent->getTag() == dwarf::DW_TAG_namespace && 1024 getDIEStringAttr(Parent, dwarf::DW_AT_name) == "") 1025 return true; 1026 Parent = Parent->getParent(); 1027 } 1028 1029 return false; 1030 } 1031 1032 /// Test if the current CU language is C++ and that we have 1033 /// a named type that is not contained in an anonymous namespace. 1034 static bool shouldAddODRHash(CompileUnit *CU, DIE *Die) { 1035 return CU->getLanguage() == dwarf::DW_LANG_C_plus_plus && 1036 getDIEStringAttr(Die, dwarf::DW_AT_name) != "" && 1037 !isContainedInAnonNamespace(Die); 1038 } 1039 1040 void DwarfDebug::finalizeModuleInfo() { 1041 // Collect info for variables that were optimized out. 1042 collectDeadVariables(); 1043 1044 // Attach DW_AT_inline attribute with inlined subprogram DIEs. 1045 computeInlinedDIEs(); 1046 1047 // Split out type units and conditionally add an ODR tag to the split 1048 // out type. 1049 // FIXME: Do type splitting. 1050 for (unsigned i = 0, e = TypeUnits.size(); i != e; ++i) { 1051 DIE *Die = TypeUnits[i]; 1052 DIEHash Hash; 1053 // If we've requested ODR hashes and it's applicable for an ODR hash then 1054 // add the ODR signature now. 1055 // FIXME: This should be added onto the type unit, not the type, but this 1056 // works as an intermediate stage. 1057 if (GenerateODRHash && shouldAddODRHash(CUMap.begin()->second, Die)) 1058 CUMap.begin()->second->addUInt(Die, dwarf::DW_AT_GNU_odr_signature, 1059 dwarf::DW_FORM_data8, 1060 Hash.computeDIEODRSignature(*Die)); 1061 } 1062 1063 // Handle anything that needs to be done on a per-cu basis. 1064 for (DenseMap<const MDNode *, CompileUnit *>::iterator CUI = CUMap.begin(), 1065 CUE = CUMap.end(); 1066 CUI != CUE; ++CUI) { 1067 CompileUnit *TheCU = CUI->second; 1068 // Emit DW_AT_containing_type attribute to connect types with their 1069 // vtable holding type. 1070 TheCU->constructContainingTypeDIEs(); 1071 1072 // If we're splitting the dwarf out now that we've got the entire 1073 // CU then construct a skeleton CU based upon it. 1074 if (useSplitDwarf()) { 1075 uint64_t ID = 0; 1076 if (GenerateCUHash) { 1077 DIEHash CUHash; 1078 ID = CUHash.computeCUSignature(*TheCU->getCUDie()); 1079 } 1080 // This should be a unique identifier when we want to build .dwp files. 1081 TheCU->addUInt(TheCU->getCUDie(), dwarf::DW_AT_GNU_dwo_id, 1082 dwarf::DW_FORM_data8, ID); 1083 // Now construct the skeleton CU associated. 1084 CompileUnit *SkCU = constructSkeletonCU(TheCU); 1085 // This should be a unique identifier when we want to build .dwp files. 1086 SkCU->addUInt(SkCU->getCUDie(), dwarf::DW_AT_GNU_dwo_id, 1087 dwarf::DW_FORM_data8, ID); 1088 } 1089 } 1090 1091 // Compute DIE offsets and sizes. 1092 InfoHolder.computeSizeAndOffsets(); 1093 if (useSplitDwarf()) 1094 SkeletonHolder.computeSizeAndOffsets(); 1095 } 1096 1097 void DwarfDebug::endSections() { 1098 // Filter labels by section. 1099 for (size_t n = 0; n < ArangeLabels.size(); n++) { 1100 const SymbolCU &SCU = ArangeLabels[n]; 1101 if (SCU.Sym->isInSection()) { 1102 // Make a note of this symbol and it's section. 1103 const MCSection *Section = &SCU.Sym->getSection(); 1104 if (!Section->getKind().isMetadata()) 1105 SectionMap[Section].push_back(SCU); 1106 } else { 1107 // Some symbols (e.g. common/bss on mach-o) can have no section but still 1108 // appear in the output. This sucks as we rely on sections to build 1109 // arange spans. We can do it without, but it's icky. 1110 SectionMap[NULL].push_back(SCU); 1111 } 1112 } 1113 1114 // Build a list of sections used. 1115 std::vector<const MCSection *> Sections; 1116 for (SectionMapType::iterator it = SectionMap.begin(); it != SectionMap.end(); 1117 it++) { 1118 const MCSection *Section = it->first; 1119 Sections.push_back(Section); 1120 } 1121 1122 // Sort the sections into order. 1123 // This is only done to ensure consistent output order across different runs. 1124 std::sort(Sections.begin(), Sections.end(), SectionSort); 1125 1126 // Add terminating symbols for each section. 1127 for (unsigned ID=0;ID<Sections.size();ID++) { 1128 const MCSection *Section = Sections[ID]; 1129 MCSymbol *Sym = NULL; 1130 1131 if (Section) { 1132 // We can't call MCSection::getLabelEndName, as it's only safe to do so 1133 // if we know the section name up-front. For user-created sections, the resulting 1134 // label may not be valid to use as a label. (section names can use a greater 1135 // set of characters on some systems) 1136 Sym = Asm->GetTempSymbol("debug_end", ID); 1137 Asm->OutStreamer.SwitchSection(Section); 1138 Asm->OutStreamer.EmitLabel(Sym); 1139 } 1140 1141 // Insert a final terminator. 1142 SectionMap[Section].push_back(SymbolCU(NULL, Sym)); 1143 } 1144 } 1145 1146 // Emit all Dwarf sections that should come after the content. 1147 void DwarfDebug::endModule() { 1148 1149 if (!FirstCU) return; 1150 1151 // End any existing sections. 1152 // TODO: Does this need to happen? 1153 endSections(); 1154 1155 // Finalize the debug info for the module. 1156 finalizeModuleInfo(); 1157 1158 if (!useSplitDwarf()) { 1159 emitDebugStr(); 1160 1161 // Emit all the DIEs into a debug info section. 1162 emitDebugInfo(); 1163 1164 // Corresponding abbreviations into a abbrev section. 1165 emitAbbreviations(); 1166 1167 // Emit info into a debug loc section. 1168 emitDebugLoc(); 1169 1170 // Emit info into a debug aranges section. 1171 emitDebugARanges(); 1172 1173 // Emit info into a debug ranges section. 1174 emitDebugRanges(); 1175 1176 // Emit info into a debug macinfo section. 1177 emitDebugMacInfo(); 1178 1179 } else { 1180 // TODO: Fill this in for separated debug sections and separate 1181 // out information into new sections. 1182 emitDebugStr(); 1183 if (useSplitDwarf()) 1184 emitDebugStrDWO(); 1185 1186 // Emit the debug info section and compile units. 1187 emitDebugInfo(); 1188 emitDebugInfoDWO(); 1189 1190 // Corresponding abbreviations into a abbrev section. 1191 emitAbbreviations(); 1192 emitDebugAbbrevDWO(); 1193 1194 // Emit info into a debug loc section. 1195 emitDebugLoc(); 1196 1197 // Emit info into a debug aranges section. 1198 emitDebugARanges(); 1199 1200 // Emit info into a debug ranges section. 1201 emitDebugRanges(); 1202 1203 // Emit info into a debug macinfo section. 1204 emitDebugMacInfo(); 1205 1206 // Emit DWO addresses. 1207 InfoHolder.emitAddresses(Asm->getObjFileLowering().getDwarfAddrSection()); 1208 1209 } 1210 1211 // Emit info into the dwarf accelerator table sections. 1212 if (useDwarfAccelTables()) { 1213 emitAccelNames(); 1214 emitAccelObjC(); 1215 emitAccelNamespaces(); 1216 emitAccelTypes(); 1217 } 1218 1219 // Emit the pubnames and pubtypes sections if requested. 1220 if (HasDwarfPubSections) { 1221 emitDebugPubNames(GenerateGnuPubSections); 1222 emitDebugPubTypes(GenerateGnuPubSections); 1223 } 1224 1225 // clean up. 1226 SPMap.clear(); 1227 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 1228 E = CUMap.end(); I != E; ++I) 1229 delete I->second; 1230 1231 for (SmallVectorImpl<CompileUnit *>::iterator I = SkeletonCUs.begin(), 1232 E = SkeletonCUs.end(); I != E; ++I) 1233 delete *I; 1234 1235 // Reset these for the next Module if we have one. 1236 FirstCU = NULL; 1237 } 1238 1239 // Find abstract variable, if any, associated with Var. 1240 DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &DV, 1241 DebugLoc ScopeLoc) { 1242 LLVMContext &Ctx = DV->getContext(); 1243 // More then one inlined variable corresponds to one abstract variable. 1244 DIVariable Var = cleanseInlinedVariable(DV, Ctx); 1245 DbgVariable *AbsDbgVariable = AbstractVariables.lookup(Var); 1246 if (AbsDbgVariable) 1247 return AbsDbgVariable; 1248 1249 LexicalScope *Scope = LScopes.findAbstractScope(ScopeLoc.getScope(Ctx)); 1250 if (!Scope) 1251 return NULL; 1252 1253 AbsDbgVariable = new DbgVariable(Var, NULL, this); 1254 addScopeVariable(Scope, AbsDbgVariable); 1255 AbstractVariables[Var] = AbsDbgVariable; 1256 return AbsDbgVariable; 1257 } 1258 1259 // If Var is a current function argument then add it to CurrentFnArguments list. 1260 bool DwarfDebug::addCurrentFnArgument(const MachineFunction *MF, 1261 DbgVariable *Var, LexicalScope *Scope) { 1262 if (!LScopes.isCurrentFunctionScope(Scope)) 1263 return false; 1264 DIVariable DV = Var->getVariable(); 1265 if (DV.getTag() != dwarf::DW_TAG_arg_variable) 1266 return false; 1267 unsigned ArgNo = DV.getArgNumber(); 1268 if (ArgNo == 0) 1269 return false; 1270 1271 size_t Size = CurrentFnArguments.size(); 1272 if (Size == 0) 1273 CurrentFnArguments.resize(MF->getFunction()->arg_size()); 1274 // llvm::Function argument size is not good indicator of how many 1275 // arguments does the function have at source level. 1276 if (ArgNo > Size) 1277 CurrentFnArguments.resize(ArgNo * 2); 1278 CurrentFnArguments[ArgNo - 1] = Var; 1279 return true; 1280 } 1281 1282 // Collect variable information from side table maintained by MMI. 1283 void 1284 DwarfDebug::collectVariableInfoFromMMITable(const MachineFunction *MF, 1285 SmallPtrSet<const MDNode *, 16> &Processed) { 1286 MachineModuleInfo::VariableDbgInfoMapTy &VMap = MMI->getVariableDbgInfo(); 1287 for (MachineModuleInfo::VariableDbgInfoMapTy::iterator VI = VMap.begin(), 1288 VE = VMap.end(); VI != VE; ++VI) { 1289 const MDNode *Var = VI->first; 1290 if (!Var) continue; 1291 Processed.insert(Var); 1292 DIVariable DV(Var); 1293 const std::pair<unsigned, DebugLoc> &VP = VI->second; 1294 1295 LexicalScope *Scope = LScopes.findLexicalScope(VP.second); 1296 1297 // If variable scope is not found then skip this variable. 1298 if (Scope == 0) 1299 continue; 1300 1301 DbgVariable *AbsDbgVariable = findAbstractVariable(DV, VP.second); 1302 DbgVariable *RegVar = new DbgVariable(DV, AbsDbgVariable, this); 1303 RegVar->setFrameIndex(VP.first); 1304 if (!addCurrentFnArgument(MF, RegVar, Scope)) 1305 addScopeVariable(Scope, RegVar); 1306 if (AbsDbgVariable) 1307 AbsDbgVariable->setFrameIndex(VP.first); 1308 } 1309 } 1310 1311 // Return true if debug value, encoded by DBG_VALUE instruction, is in a 1312 // defined reg. 1313 static bool isDbgValueInDefinedReg(const MachineInstr *MI) { 1314 assert(MI->isDebugValue() && "Invalid DBG_VALUE machine instruction!"); 1315 return MI->getNumOperands() == 3 && 1316 MI->getOperand(0).isReg() && MI->getOperand(0).getReg() && 1317 (MI->getOperand(1).isImm() || 1318 (MI->getOperand(1).isReg() && MI->getOperand(1).getReg() == 0U)); 1319 } 1320 1321 // Get .debug_loc entry for the instruction range starting at MI. 1322 static DotDebugLocEntry getDebugLocEntry(AsmPrinter *Asm, 1323 const MCSymbol *FLabel, 1324 const MCSymbol *SLabel, 1325 const MachineInstr *MI) { 1326 const MDNode *Var = MI->getOperand(MI->getNumOperands() - 1).getMetadata(); 1327 1328 assert(MI->getNumOperands() == 3); 1329 if (MI->getOperand(0).isReg()) { 1330 MachineLocation MLoc; 1331 // If the second operand is an immediate, this is a 1332 // register-indirect address. 1333 if (!MI->getOperand(1).isImm()) 1334 MLoc.set(MI->getOperand(0).getReg()); 1335 else 1336 MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm()); 1337 return DotDebugLocEntry(FLabel, SLabel, MLoc, Var); 1338 } 1339 if (MI->getOperand(0).isImm()) 1340 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getImm()); 1341 if (MI->getOperand(0).isFPImm()) 1342 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getFPImm()); 1343 if (MI->getOperand(0).isCImm()) 1344 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getCImm()); 1345 1346 llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!"); 1347 } 1348 1349 // Find variables for each lexical scope. 1350 void 1351 DwarfDebug::collectVariableInfo(const MachineFunction *MF, 1352 SmallPtrSet<const MDNode *, 16> &Processed) { 1353 1354 // Grab the variable info that was squirreled away in the MMI side-table. 1355 collectVariableInfoFromMMITable(MF, Processed); 1356 1357 for (SmallVectorImpl<const MDNode*>::const_iterator 1358 UVI = UserVariables.begin(), UVE = UserVariables.end(); UVI != UVE; 1359 ++UVI) { 1360 const MDNode *Var = *UVI; 1361 if (Processed.count(Var)) 1362 continue; 1363 1364 // History contains relevant DBG_VALUE instructions for Var and instructions 1365 // clobbering it. 1366 SmallVectorImpl<const MachineInstr*> &History = DbgValues[Var]; 1367 if (History.empty()) 1368 continue; 1369 const MachineInstr *MInsn = History.front(); 1370 1371 DIVariable DV(Var); 1372 LexicalScope *Scope = NULL; 1373 if (DV.getTag() == dwarf::DW_TAG_arg_variable && 1374 DISubprogram(DV.getContext()).describes(MF->getFunction())) 1375 Scope = LScopes.getCurrentFunctionScope(); 1376 else if (MDNode *IA = DV.getInlinedAt()) 1377 Scope = LScopes.findInlinedScope(DebugLoc::getFromDILocation(IA)); 1378 else 1379 Scope = LScopes.findLexicalScope(cast<MDNode>(DV->getOperand(1))); 1380 // If variable scope is not found then skip this variable. 1381 if (!Scope) 1382 continue; 1383 1384 Processed.insert(DV); 1385 assert(MInsn->isDebugValue() && "History must begin with debug value"); 1386 DbgVariable *AbsVar = findAbstractVariable(DV, MInsn->getDebugLoc()); 1387 DbgVariable *RegVar = new DbgVariable(DV, AbsVar, this); 1388 if (!addCurrentFnArgument(MF, RegVar, Scope)) 1389 addScopeVariable(Scope, RegVar); 1390 if (AbsVar) 1391 AbsVar->setMInsn(MInsn); 1392 1393 // Simplify ranges that are fully coalesced. 1394 if (History.size() <= 1 || (History.size() == 2 && 1395 MInsn->isIdenticalTo(History.back()))) { 1396 RegVar->setMInsn(MInsn); 1397 continue; 1398 } 1399 1400 // Handle multiple DBG_VALUE instructions describing one variable. 1401 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size()); 1402 1403 for (SmallVectorImpl<const MachineInstr*>::const_iterator 1404 HI = History.begin(), HE = History.end(); HI != HE; ++HI) { 1405 const MachineInstr *Begin = *HI; 1406 assert(Begin->isDebugValue() && "Invalid History entry"); 1407 1408 // Check if DBG_VALUE is truncating a range. 1409 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() 1410 && !Begin->getOperand(0).getReg()) 1411 continue; 1412 1413 // Compute the range for a register location. 1414 const MCSymbol *FLabel = getLabelBeforeInsn(Begin); 1415 const MCSymbol *SLabel = 0; 1416 1417 if (HI + 1 == HE) 1418 // If Begin is the last instruction in History then its value is valid 1419 // until the end of the function. 1420 SLabel = FunctionEndSym; 1421 else { 1422 const MachineInstr *End = HI[1]; 1423 DEBUG(dbgs() << "DotDebugLoc Pair:\n" 1424 << "\t" << *Begin << "\t" << *End << "\n"); 1425 if (End->isDebugValue()) 1426 SLabel = getLabelBeforeInsn(End); 1427 else { 1428 // End is a normal instruction clobbering the range. 1429 SLabel = getLabelAfterInsn(End); 1430 assert(SLabel && "Forgot label after clobber instruction"); 1431 ++HI; 1432 } 1433 } 1434 1435 // The value is valid until the next DBG_VALUE or clobber. 1436 DotDebugLocEntries.push_back(getDebugLocEntry(Asm, FLabel, SLabel, 1437 Begin)); 1438 } 1439 DotDebugLocEntries.push_back(DotDebugLocEntry()); 1440 } 1441 1442 // Collect info for variables that were optimized out. 1443 LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); 1444 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables(); 1445 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) { 1446 DIVariable DV(Variables.getElement(i)); 1447 if (!DV || !DV.isVariable() || !Processed.insert(DV)) 1448 continue; 1449 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext())) 1450 addScopeVariable(Scope, new DbgVariable(DV, NULL, this)); 1451 } 1452 } 1453 1454 // Return Label preceding the instruction. 1455 MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) { 1456 MCSymbol *Label = LabelsBeforeInsn.lookup(MI); 1457 assert(Label && "Didn't insert label before instruction"); 1458 return Label; 1459 } 1460 1461 // Return Label immediately following the instruction. 1462 MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) { 1463 return LabelsAfterInsn.lookup(MI); 1464 } 1465 1466 // Process beginning of an instruction. 1467 void DwarfDebug::beginInstruction(const MachineInstr *MI) { 1468 // Check if source location changes, but ignore DBG_VALUE locations. 1469 if (!MI->isDebugValue()) { 1470 DebugLoc DL = MI->getDebugLoc(); 1471 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) { 1472 unsigned Flags = 0; 1473 PrevInstLoc = DL; 1474 if (DL == PrologEndLoc) { 1475 Flags |= DWARF2_FLAG_PROLOGUE_END; 1476 PrologEndLoc = DebugLoc(); 1477 } 1478 if (PrologEndLoc.isUnknown()) 1479 Flags |= DWARF2_FLAG_IS_STMT; 1480 1481 if (!DL.isUnknown()) { 1482 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext()); 1483 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags); 1484 } else 1485 recordSourceLine(0, 0, 0, 0); 1486 } 1487 } 1488 1489 // Insert labels where requested. 1490 DenseMap<const MachineInstr*, MCSymbol*>::iterator I = 1491 LabelsBeforeInsn.find(MI); 1492 1493 // No label needed. 1494 if (I == LabelsBeforeInsn.end()) 1495 return; 1496 1497 // Label already assigned. 1498 if (I->second) 1499 return; 1500 1501 if (!PrevLabel) { 1502 PrevLabel = MMI->getContext().CreateTempSymbol(); 1503 Asm->OutStreamer.EmitLabel(PrevLabel); 1504 } 1505 I->second = PrevLabel; 1506 } 1507 1508 // Process end of an instruction. 1509 void DwarfDebug::endInstruction(const MachineInstr *MI) { 1510 // Don't create a new label after DBG_VALUE instructions. 1511 // They don't generate code. 1512 if (!MI->isDebugValue()) 1513 PrevLabel = 0; 1514 1515 DenseMap<const MachineInstr*, MCSymbol*>::iterator I = 1516 LabelsAfterInsn.find(MI); 1517 1518 // No label needed. 1519 if (I == LabelsAfterInsn.end()) 1520 return; 1521 1522 // Label already assigned. 1523 if (I->second) 1524 return; 1525 1526 // We need a label after this instruction. 1527 if (!PrevLabel) { 1528 PrevLabel = MMI->getContext().CreateTempSymbol(); 1529 Asm->OutStreamer.EmitLabel(PrevLabel); 1530 } 1531 I->second = PrevLabel; 1532 } 1533 1534 // Each LexicalScope has first instruction and last instruction to mark 1535 // beginning and end of a scope respectively. Create an inverse map that list 1536 // scopes starts (and ends) with an instruction. One instruction may start (or 1537 // end) multiple scopes. Ignore scopes that are not reachable. 1538 void DwarfDebug::identifyScopeMarkers() { 1539 SmallVector<LexicalScope *, 4> WorkList; 1540 WorkList.push_back(LScopes.getCurrentFunctionScope()); 1541 while (!WorkList.empty()) { 1542 LexicalScope *S = WorkList.pop_back_val(); 1543 1544 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren(); 1545 if (!Children.empty()) 1546 for (SmallVectorImpl<LexicalScope *>::const_iterator SI = Children.begin(), 1547 SE = Children.end(); SI != SE; ++SI) 1548 WorkList.push_back(*SI); 1549 1550 if (S->isAbstractScope()) 1551 continue; 1552 1553 const SmallVectorImpl<InsnRange> &Ranges = S->getRanges(); 1554 if (Ranges.empty()) 1555 continue; 1556 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 1557 RE = Ranges.end(); RI != RE; ++RI) { 1558 assert(RI->first && "InsnRange does not have first instruction!"); 1559 assert(RI->second && "InsnRange does not have second instruction!"); 1560 requestLabelBeforeInsn(RI->first); 1561 requestLabelAfterInsn(RI->second); 1562 } 1563 } 1564 } 1565 1566 // Get MDNode for DebugLoc's scope. 1567 static MDNode *getScopeNode(DebugLoc DL, const LLVMContext &Ctx) { 1568 if (MDNode *InlinedAt = DL.getInlinedAt(Ctx)) 1569 return getScopeNode(DebugLoc::getFromDILocation(InlinedAt), Ctx); 1570 return DL.getScope(Ctx); 1571 } 1572 1573 // Walk up the scope chain of given debug loc and find line number info 1574 // for the function. 1575 static DebugLoc getFnDebugLoc(DebugLoc DL, const LLVMContext &Ctx) { 1576 const MDNode *Scope = getScopeNode(DL, Ctx); 1577 DISubprogram SP = getDISubprogram(Scope); 1578 if (SP.isSubprogram()) { 1579 // Check for number of operands since the compatibility is 1580 // cheap here. 1581 if (SP->getNumOperands() > 19) 1582 return DebugLoc::get(SP.getScopeLineNumber(), 0, SP); 1583 else 1584 return DebugLoc::get(SP.getLineNumber(), 0, SP); 1585 } 1586 1587 return DebugLoc(); 1588 } 1589 1590 // Gather pre-function debug information. Assumes being called immediately 1591 // after the function entry point has been emitted. 1592 void DwarfDebug::beginFunction(const MachineFunction *MF) { 1593 1594 // If there's no debug info for the function we're not going to do anything. 1595 if (!MMI->hasDebugInfo()) 1596 return; 1597 1598 // Grab the lexical scopes for the function, if we don't have any of those 1599 // then we're not going to be able to do anything. 1600 LScopes.initialize(*MF); 1601 if (LScopes.empty()) 1602 return; 1603 1604 assert(UserVariables.empty() && DbgValues.empty() && "Maps weren't cleaned"); 1605 1606 // Make sure that each lexical scope will have a begin/end label. 1607 identifyScopeMarkers(); 1608 1609 // Set DwarfCompileUnitID in MCContext to the Compile Unit this function 1610 // belongs to so that we add to the correct per-cu line table in the 1611 // non-asm case. 1612 LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); 1613 CompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode()); 1614 assert(TheCU && "Unable to find compile unit!"); 1615 if (Asm->TM.hasMCUseLoc() && Asm->OutStreamer.hasRawTextSupport()) 1616 // Use a single line table if we are using .loc and generating assembly. 1617 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0); 1618 else 1619 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID()); 1620 1621 // Emit a label for the function so that we have a beginning address. 1622 FunctionBeginSym = Asm->GetTempSymbol("func_begin", Asm->getFunctionNumber()); 1623 // Assumes in correct section after the entry point. 1624 Asm->OutStreamer.EmitLabel(FunctionBeginSym); 1625 1626 const TargetRegisterInfo *TRI = Asm->TM.getRegisterInfo(); 1627 // LiveUserVar - Map physreg numbers to the MDNode they contain. 1628 std::vector<const MDNode *> LiveUserVar(TRI->getNumRegs()); 1629 1630 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end(); I != E; 1631 ++I) { 1632 bool AtBlockEntry = true; 1633 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end(); 1634 II != IE; ++II) { 1635 const MachineInstr *MI = II; 1636 1637 if (MI->isDebugValue()) { 1638 assert(MI->getNumOperands() > 1 && "Invalid machine instruction!"); 1639 1640 // Keep track of user variables. 1641 const MDNode *Var = 1642 MI->getOperand(MI->getNumOperands() - 1).getMetadata(); 1643 1644 // Variable is in a register, we need to check for clobbers. 1645 if (isDbgValueInDefinedReg(MI)) 1646 LiveUserVar[MI->getOperand(0).getReg()] = Var; 1647 1648 // Check the history of this variable. 1649 SmallVectorImpl<const MachineInstr *> &History = DbgValues[Var]; 1650 if (History.empty()) { 1651 UserVariables.push_back(Var); 1652 // The first mention of a function argument gets the FunctionBeginSym 1653 // label, so arguments are visible when breaking at function entry. 1654 DIVariable DV(Var); 1655 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable && 1656 getDISubprogram(DV.getContext()).describes(MF->getFunction())) 1657 LabelsBeforeInsn[MI] = FunctionBeginSym; 1658 } else { 1659 // We have seen this variable before. Try to coalesce DBG_VALUEs. 1660 const MachineInstr *Prev = History.back(); 1661 if (Prev->isDebugValue()) { 1662 // Coalesce identical entries at the end of History. 1663 if (History.size() >= 2 && 1664 Prev->isIdenticalTo(History[History.size() - 2])) { 1665 DEBUG(dbgs() << "Coalescing identical DBG_VALUE entries:\n" 1666 << "\t" << *Prev << "\t" 1667 << *History[History.size() - 2] << "\n"); 1668 History.pop_back(); 1669 } 1670 1671 // Terminate old register assignments that don't reach MI; 1672 MachineFunction::const_iterator PrevMBB = Prev->getParent(); 1673 if (PrevMBB != I && (!AtBlockEntry || llvm::next(PrevMBB) != I) && 1674 isDbgValueInDefinedReg(Prev)) { 1675 // Previous register assignment needs to terminate at the end of 1676 // its basic block. 1677 MachineBasicBlock::const_iterator LastMI = 1678 PrevMBB->getLastNonDebugInstr(); 1679 if (LastMI == PrevMBB->end()) { 1680 // Drop DBG_VALUE for empty range. 1681 DEBUG(dbgs() << "Dropping DBG_VALUE for empty range:\n" 1682 << "\t" << *Prev << "\n"); 1683 History.pop_back(); 1684 } else if (llvm::next(PrevMBB) != PrevMBB->getParent()->end()) 1685 // Terminate after LastMI. 1686 History.push_back(LastMI); 1687 } 1688 } 1689 } 1690 History.push_back(MI); 1691 } else { 1692 // Not a DBG_VALUE instruction. 1693 if (!MI->isLabel()) 1694 AtBlockEntry = false; 1695 1696 // First known non-DBG_VALUE and non-frame setup location marks 1697 // the beginning of the function body. 1698 if (!MI->getFlag(MachineInstr::FrameSetup) && 1699 (PrologEndLoc.isUnknown() && !MI->getDebugLoc().isUnknown())) 1700 PrologEndLoc = MI->getDebugLoc(); 1701 1702 // Check if the instruction clobbers any registers with debug vars. 1703 for (MachineInstr::const_mop_iterator MOI = MI->operands_begin(), 1704 MOE = MI->operands_end(); 1705 MOI != MOE; ++MOI) { 1706 if (!MOI->isReg() || !MOI->isDef() || !MOI->getReg()) 1707 continue; 1708 for (MCRegAliasIterator AI(MOI->getReg(), TRI, true); AI.isValid(); 1709 ++AI) { 1710 unsigned Reg = *AI; 1711 const MDNode *Var = LiveUserVar[Reg]; 1712 if (!Var) 1713 continue; 1714 // Reg is now clobbered. 1715 LiveUserVar[Reg] = 0; 1716 1717 // Was MD last defined by a DBG_VALUE referring to Reg? 1718 DbgValueHistoryMap::iterator HistI = DbgValues.find(Var); 1719 if (HistI == DbgValues.end()) 1720 continue; 1721 SmallVectorImpl<const MachineInstr *> &History = HistI->second; 1722 if (History.empty()) 1723 continue; 1724 const MachineInstr *Prev = History.back(); 1725 // Sanity-check: Register assignments are terminated at the end of 1726 // their block. 1727 if (!Prev->isDebugValue() || Prev->getParent() != MI->getParent()) 1728 continue; 1729 // Is the variable still in Reg? 1730 if (!isDbgValueInDefinedReg(Prev) || 1731 Prev->getOperand(0).getReg() != Reg) 1732 continue; 1733 // Var is clobbered. Make sure the next instruction gets a label. 1734 History.push_back(MI); 1735 } 1736 } 1737 } 1738 } 1739 } 1740 1741 for (DbgValueHistoryMap::iterator I = DbgValues.begin(), E = DbgValues.end(); 1742 I != E; ++I) { 1743 SmallVectorImpl<const MachineInstr *> &History = I->second; 1744 if (History.empty()) 1745 continue; 1746 1747 // Make sure the final register assignments are terminated. 1748 const MachineInstr *Prev = History.back(); 1749 if (Prev->isDebugValue() && isDbgValueInDefinedReg(Prev)) { 1750 const MachineBasicBlock *PrevMBB = Prev->getParent(); 1751 MachineBasicBlock::const_iterator LastMI = 1752 PrevMBB->getLastNonDebugInstr(); 1753 if (LastMI == PrevMBB->end()) 1754 // Drop DBG_VALUE for empty range. 1755 History.pop_back(); 1756 else if (PrevMBB != &PrevMBB->getParent()->back()) { 1757 // Terminate after LastMI. 1758 History.push_back(LastMI); 1759 } 1760 } 1761 // Request labels for the full history. 1762 for (unsigned i = 0, e = History.size(); i != e; ++i) { 1763 const MachineInstr *MI = History[i]; 1764 if (MI->isDebugValue()) 1765 requestLabelBeforeInsn(MI); 1766 else 1767 requestLabelAfterInsn(MI); 1768 } 1769 } 1770 1771 PrevInstLoc = DebugLoc(); 1772 PrevLabel = FunctionBeginSym; 1773 1774 // Record beginning of function. 1775 if (!PrologEndLoc.isUnknown()) { 1776 DebugLoc FnStartDL = 1777 getFnDebugLoc(PrologEndLoc, MF->getFunction()->getContext()); 1778 recordSourceLine( 1779 FnStartDL.getLine(), FnStartDL.getCol(), 1780 FnStartDL.getScope(MF->getFunction()->getContext()), 1781 // We'd like to list the prologue as "not statements" but GDB behaves 1782 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing. 1783 DWARF2_FLAG_IS_STMT); 1784 } 1785 } 1786 1787 void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) { 1788 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS]; 1789 DIVariable DV = Var->getVariable(); 1790 // Variables with positive arg numbers are parameters. 1791 if (unsigned ArgNum = DV.getArgNumber()) { 1792 // Keep all parameters in order at the start of the variable list to ensure 1793 // function types are correct (no out-of-order parameters) 1794 // 1795 // This could be improved by only doing it for optimized builds (unoptimized 1796 // builds have the right order to begin with), searching from the back (this 1797 // would catch the unoptimized case quickly), or doing a binary search 1798 // rather than linear search. 1799 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin(); 1800 while (I != Vars.end()) { 1801 unsigned CurNum = (*I)->getVariable().getArgNumber(); 1802 // A local (non-parameter) variable has been found, insert immediately 1803 // before it. 1804 if (CurNum == 0) 1805 break; 1806 // A later indexed parameter has been found, insert immediately before it. 1807 if (CurNum > ArgNum) 1808 break; 1809 ++I; 1810 } 1811 Vars.insert(I, Var); 1812 return; 1813 } 1814 1815 Vars.push_back(Var); 1816 } 1817 1818 // Gather and emit post-function debug information. 1819 void DwarfDebug::endFunction(const MachineFunction *MF) { 1820 if (!MMI->hasDebugInfo() || LScopes.empty()) return; 1821 1822 // Define end label for subprogram. 1823 FunctionEndSym = Asm->GetTempSymbol("func_end", 1824 Asm->getFunctionNumber()); 1825 // Assumes in correct section after the entry point. 1826 Asm->OutStreamer.EmitLabel(FunctionEndSym); 1827 // Set DwarfCompileUnitID in MCContext to default value. 1828 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0); 1829 1830 SmallPtrSet<const MDNode *, 16> ProcessedVars; 1831 collectVariableInfo(MF, ProcessedVars); 1832 1833 LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); 1834 CompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode()); 1835 assert(TheCU && "Unable to find compile unit!"); 1836 1837 // Construct abstract scopes. 1838 ArrayRef<LexicalScope *> AList = LScopes.getAbstractScopesList(); 1839 for (unsigned i = 0, e = AList.size(); i != e; ++i) { 1840 LexicalScope *AScope = AList[i]; 1841 DISubprogram SP(AScope->getScopeNode()); 1842 if (SP.isSubprogram()) { 1843 // Collect info for variables that were optimized out. 1844 DIArray Variables = SP.getVariables(); 1845 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) { 1846 DIVariable DV(Variables.getElement(i)); 1847 if (!DV || !DV.isVariable() || !ProcessedVars.insert(DV)) 1848 continue; 1849 // Check that DbgVariable for DV wasn't created earlier, when 1850 // findAbstractVariable() was called for inlined instance of DV. 1851 LLVMContext &Ctx = DV->getContext(); 1852 DIVariable CleanDV = cleanseInlinedVariable(DV, Ctx); 1853 if (AbstractVariables.lookup(CleanDV)) 1854 continue; 1855 if (LexicalScope *Scope = LScopes.findAbstractScope(DV.getContext())) 1856 addScopeVariable(Scope, new DbgVariable(DV, NULL, this)); 1857 } 1858 } 1859 if (ProcessedSPNodes.count(AScope->getScopeNode()) == 0) 1860 constructScopeDIE(TheCU, AScope); 1861 } 1862 1863 DIE *CurFnDIE = constructScopeDIE(TheCU, FnScope); 1864 1865 if (!MF->getTarget().Options.DisableFramePointerElim(*MF)) 1866 TheCU->addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr); 1867 1868 // Clear debug info 1869 for (ScopeVariablesMap::iterator 1870 I = ScopeVariables.begin(), E = ScopeVariables.end(); I != E; ++I) 1871 DeleteContainerPointers(I->second); 1872 ScopeVariables.clear(); 1873 DeleteContainerPointers(CurrentFnArguments); 1874 UserVariables.clear(); 1875 DbgValues.clear(); 1876 AbstractVariables.clear(); 1877 LabelsBeforeInsn.clear(); 1878 LabelsAfterInsn.clear(); 1879 PrevLabel = NULL; 1880 } 1881 1882 // Register a source line with debug info. Returns the unique label that was 1883 // emitted and which provides correspondence to the source line list. 1884 void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S, 1885 unsigned Flags) { 1886 StringRef Fn; 1887 StringRef Dir; 1888 unsigned Src = 1; 1889 if (S) { 1890 DIDescriptor Scope(S); 1891 1892 if (Scope.isCompileUnit()) { 1893 DICompileUnit CU(S); 1894 Fn = CU.getFilename(); 1895 Dir = CU.getDirectory(); 1896 } else if (Scope.isFile()) { 1897 DIFile F(S); 1898 Fn = F.getFilename(); 1899 Dir = F.getDirectory(); 1900 } else if (Scope.isSubprogram()) { 1901 DISubprogram SP(S); 1902 Fn = SP.getFilename(); 1903 Dir = SP.getDirectory(); 1904 } else if (Scope.isLexicalBlockFile()) { 1905 DILexicalBlockFile DBF(S); 1906 Fn = DBF.getFilename(); 1907 Dir = DBF.getDirectory(); 1908 } else if (Scope.isLexicalBlock()) { 1909 DILexicalBlock DB(S); 1910 Fn = DB.getFilename(); 1911 Dir = DB.getDirectory(); 1912 } else 1913 llvm_unreachable("Unexpected scope info"); 1914 1915 Src = getOrCreateSourceID(Fn, Dir, 1916 Asm->OutStreamer.getContext().getDwarfCompileUnitID()); 1917 } 1918 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0, 0, Fn); 1919 } 1920 1921 //===----------------------------------------------------------------------===// 1922 // Emit Methods 1923 //===----------------------------------------------------------------------===// 1924 1925 // Compute the size and offset of a DIE. The offset is relative to start of the 1926 // CU. It returns the offset after laying out the DIE. 1927 unsigned 1928 DwarfUnits::computeSizeAndOffset(DIE *Die, unsigned Offset) { 1929 // Get the children. 1930 const std::vector<DIE *> &Children = Die->getChildren(); 1931 1932 // Record the abbreviation. 1933 assignAbbrevNumber(Die->getAbbrev()); 1934 1935 // Get the abbreviation for this DIE. 1936 unsigned AbbrevNumber = Die->getAbbrevNumber(); 1937 const DIEAbbrev *Abbrev = Abbreviations[AbbrevNumber - 1]; 1938 1939 // Set DIE offset 1940 Die->setOffset(Offset); 1941 1942 // Start the size with the size of abbreviation code. 1943 Offset += MCAsmInfo::getULEB128Size(AbbrevNumber); 1944 1945 const SmallVectorImpl<DIEValue*> &Values = Die->getValues(); 1946 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev->getData(); 1947 1948 // Size the DIE attribute values. 1949 for (unsigned i = 0, N = Values.size(); i < N; ++i) 1950 // Size attribute value. 1951 Offset += Values[i]->SizeOf(Asm, AbbrevData[i].getForm()); 1952 1953 // Size the DIE children if any. 1954 if (!Children.empty()) { 1955 assert(Abbrev->getChildrenFlag() == dwarf::DW_CHILDREN_yes && 1956 "Children flag not set"); 1957 1958 for (unsigned j = 0, M = Children.size(); j < M; ++j) 1959 Offset = computeSizeAndOffset(Children[j], Offset); 1960 1961 // End of children marker. 1962 Offset += sizeof(int8_t); 1963 } 1964 1965 Die->setSize(Offset - Die->getOffset()); 1966 return Offset; 1967 } 1968 1969 // Compute the size and offset for each DIE. 1970 void DwarfUnits::computeSizeAndOffsets() { 1971 // Offset from the first CU in the debug info section is 0 initially. 1972 unsigned SecOffset = 0; 1973 1974 // Iterate over each compile unit and set the size and offsets for each 1975 // DIE within each compile unit. All offsets are CU relative. 1976 for (SmallVectorImpl<CompileUnit *>::iterator I = CUs.begin(), 1977 E = CUs.end(); I != E; ++I) { 1978 (*I)->setDebugInfoOffset(SecOffset); 1979 1980 // CU-relative offset is reset to 0 here. 1981 unsigned Offset = sizeof(int32_t) + // Length of Unit Info 1982 (*I)->getHeaderSize(); // Unit-specific headers 1983 1984 // EndOffset here is CU-relative, after laying out 1985 // all of the CU DIE. 1986 unsigned EndOffset = computeSizeAndOffset((*I)->getCUDie(), Offset); 1987 SecOffset += EndOffset; 1988 } 1989 } 1990 1991 // Emit initial Dwarf sections with a label at the start of each one. 1992 void DwarfDebug::emitSectionLabels() { 1993 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); 1994 1995 // Dwarf sections base addresses. 1996 DwarfInfoSectionSym = 1997 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info"); 1998 DwarfAbbrevSectionSym = 1999 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev"); 2000 if (useSplitDwarf()) 2001 DwarfAbbrevDWOSectionSym = 2002 emitSectionSym(Asm, TLOF.getDwarfAbbrevDWOSection(), 2003 "section_abbrev_dwo"); 2004 emitSectionSym(Asm, TLOF.getDwarfARangesSection()); 2005 2006 if (const MCSection *MacroInfo = TLOF.getDwarfMacroInfoSection()) 2007 emitSectionSym(Asm, MacroInfo); 2008 2009 DwarfLineSectionSym = 2010 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line"); 2011 emitSectionSym(Asm, TLOF.getDwarfLocSection()); 2012 if (GenerateGnuPubSections) { 2013 DwarfGnuPubNamesSectionSym = 2014 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection()); 2015 DwarfGnuPubTypesSectionSym = 2016 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection()); 2017 } else if (HasDwarfPubSections) { 2018 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection()); 2019 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection()); 2020 } 2021 2022 DwarfStrSectionSym = 2023 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string"); 2024 if (useSplitDwarf()) { 2025 DwarfStrDWOSectionSym = 2026 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string"); 2027 DwarfAddrSectionSym = 2028 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec"); 2029 } 2030 DwarfDebugRangeSectionSym = emitSectionSym(Asm, TLOF.getDwarfRangesSection(), 2031 "debug_range"); 2032 2033 DwarfDebugLocSectionSym = emitSectionSym(Asm, TLOF.getDwarfLocSection(), 2034 "section_debug_loc"); 2035 2036 TextSectionSym = emitSectionSym(Asm, TLOF.getTextSection(), "text_begin"); 2037 emitSectionSym(Asm, TLOF.getDataSection()); 2038 } 2039 2040 // Recursively emits a debug information entry. 2041 void DwarfDebug::emitDIE(DIE *Die, ArrayRef<DIEAbbrev *> Abbrevs) { 2042 // Get the abbreviation for this DIE. 2043 unsigned AbbrevNumber = Die->getAbbrevNumber(); 2044 const DIEAbbrev *Abbrev = Abbrevs[AbbrevNumber - 1]; 2045 2046 // Emit the code (index) for the abbreviation. 2047 if (Asm->isVerbose()) 2048 Asm->OutStreamer.AddComment("Abbrev [" + Twine(AbbrevNumber) + "] 0x" + 2049 Twine::utohexstr(Die->getOffset()) + ":0x" + 2050 Twine::utohexstr(Die->getSize()) + " " + 2051 dwarf::TagString(Abbrev->getTag())); 2052 Asm->EmitULEB128(AbbrevNumber); 2053 2054 const SmallVectorImpl<DIEValue*> &Values = Die->getValues(); 2055 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev->getData(); 2056 2057 // Emit the DIE attribute values. 2058 for (unsigned i = 0, N = Values.size(); i < N; ++i) { 2059 dwarf::Attribute Attr = AbbrevData[i].getAttribute(); 2060 dwarf::Form Form = AbbrevData[i].getForm(); 2061 assert(Form && "Too many attributes for DIE (check abbreviation)"); 2062 2063 if (Asm->isVerbose()) 2064 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr)); 2065 2066 switch (Attr) { 2067 case dwarf::DW_AT_abstract_origin: 2068 case dwarf::DW_AT_type: 2069 case dwarf::DW_AT_friend: 2070 case dwarf::DW_AT_specification: 2071 case dwarf::DW_AT_import: 2072 case dwarf::DW_AT_containing_type: { 2073 DIEEntry *E = cast<DIEEntry>(Values[i]); 2074 DIE *Origin = E->getEntry(); 2075 unsigned Addr = Origin->getOffset(); 2076 if (Form == dwarf::DW_FORM_ref_addr) { 2077 assert(!useSplitDwarf() && "TODO: dwo files can't have relocations."); 2078 // For DW_FORM_ref_addr, output the offset from beginning of debug info 2079 // section. Origin->getOffset() returns the offset from start of the 2080 // compile unit. 2081 CompileUnit *CU = CUDieMap.lookup(Origin->getCompileUnit()); 2082 assert(CU && "CUDie should belong to a CU."); 2083 Addr += CU->getDebugInfoOffset(); 2084 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2085 Asm->EmitLabelPlusOffset(DwarfInfoSectionSym, Addr, 2086 DIEEntry::getRefAddrSize(Asm)); 2087 else 2088 Asm->EmitLabelOffsetDifference(DwarfInfoSectionSym, Addr, 2089 DwarfInfoSectionSym, 2090 DIEEntry::getRefAddrSize(Asm)); 2091 } else { 2092 // Make sure Origin belong to the same CU. 2093 assert(Die->getCompileUnit() == Origin->getCompileUnit() && 2094 "The referenced DIE should belong to the same CU in ref4"); 2095 Asm->EmitInt32(Addr); 2096 } 2097 break; 2098 } 2099 case dwarf::DW_AT_ranges: { 2100 // DW_AT_range Value encodes offset in debug_range section. 2101 DIEInteger *V = cast<DIEInteger>(Values[i]); 2102 2103 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) { 2104 Asm->EmitLabelPlusOffset(DwarfDebugRangeSectionSym, 2105 V->getValue(), 2106 4); 2107 } else { 2108 Asm->EmitLabelOffsetDifference(DwarfDebugRangeSectionSym, 2109 V->getValue(), 2110 DwarfDebugRangeSectionSym, 2111 4); 2112 } 2113 break; 2114 } 2115 case dwarf::DW_AT_location: { 2116 if (DIELabel *L = dyn_cast<DIELabel>(Values[i])) { 2117 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2118 Asm->EmitSectionOffset(L->getValue(), DwarfDebugLocSectionSym); 2119 else 2120 Asm->EmitLabelDifference(L->getValue(), DwarfDebugLocSectionSym, 4); 2121 } else { 2122 Values[i]->EmitValue(Asm, Form); 2123 } 2124 break; 2125 } 2126 case dwarf::DW_AT_accessibility: { 2127 if (Asm->isVerbose()) { 2128 DIEInteger *V = cast<DIEInteger>(Values[i]); 2129 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(V->getValue())); 2130 } 2131 Values[i]->EmitValue(Asm, Form); 2132 break; 2133 } 2134 default: 2135 // Emit an attribute using the defined form. 2136 Values[i]->EmitValue(Asm, Form); 2137 break; 2138 } 2139 } 2140 2141 // Emit the DIE children if any. 2142 if (Abbrev->getChildrenFlag() == dwarf::DW_CHILDREN_yes) { 2143 const std::vector<DIE *> &Children = Die->getChildren(); 2144 2145 for (unsigned j = 0, M = Children.size(); j < M; ++j) 2146 emitDIE(Children[j], Abbrevs); 2147 2148 if (Asm->isVerbose()) 2149 Asm->OutStreamer.AddComment("End Of Children Mark"); 2150 Asm->EmitInt8(0); 2151 } 2152 } 2153 2154 // Emit the various dwarf units to the unit section USection with 2155 // the abbreviations going into ASection. 2156 void DwarfUnits::emitUnits(DwarfDebug *DD, 2157 const MCSection *USection, 2158 const MCSection *ASection, 2159 const MCSymbol *ASectionSym) { 2160 Asm->OutStreamer.SwitchSection(USection); 2161 for (SmallVectorImpl<CompileUnit *>::iterator I = CUs.begin(), 2162 E = CUs.end(); I != E; ++I) { 2163 CompileUnit *TheCU = *I; 2164 DIE *Die = TheCU->getCUDie(); 2165 2166 // Emit the compile units header. 2167 Asm->OutStreamer 2168 .EmitLabel(Asm->GetTempSymbol(USection->getLabelBeginName(), 2169 TheCU->getUniqueID())); 2170 2171 // Emit size of content not including length itself 2172 Asm->OutStreamer.AddComment("Length of Unit"); 2173 Asm->EmitInt32(TheCU->getHeaderSize() + Die->getSize()); 2174 2175 TheCU->emitHeader(ASection, ASectionSym); 2176 2177 DD->emitDIE(Die, Abbreviations); 2178 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol(USection->getLabelEndName(), 2179 TheCU->getUniqueID())); 2180 } 2181 } 2182 2183 // Emit the debug info section. 2184 void DwarfDebug::emitDebugInfo() { 2185 DwarfUnits &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; 2186 2187 Holder.emitUnits(this, Asm->getObjFileLowering().getDwarfInfoSection(), 2188 Asm->getObjFileLowering().getDwarfAbbrevSection(), 2189 DwarfAbbrevSectionSym); 2190 } 2191 2192 // Emit the abbreviation section. 2193 void DwarfDebug::emitAbbreviations() { 2194 if (!useSplitDwarf()) 2195 emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection(), 2196 &Abbreviations); 2197 else 2198 emitSkeletonAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection()); 2199 } 2200 2201 void DwarfDebug::emitAbbrevs(const MCSection *Section, 2202 std::vector<DIEAbbrev *> *Abbrevs) { 2203 // Check to see if it is worth the effort. 2204 if (!Abbrevs->empty()) { 2205 // Start the debug abbrev section. 2206 Asm->OutStreamer.SwitchSection(Section); 2207 2208 MCSymbol *Begin = Asm->GetTempSymbol(Section->getLabelBeginName()); 2209 Asm->OutStreamer.EmitLabel(Begin); 2210 2211 // For each abbrevation. 2212 for (unsigned i = 0, N = Abbrevs->size(); i < N; ++i) { 2213 // Get abbreviation data 2214 const DIEAbbrev *Abbrev = Abbrevs->at(i); 2215 2216 // Emit the abbrevations code (base 1 index.) 2217 Asm->EmitULEB128(Abbrev->getNumber(), "Abbreviation Code"); 2218 2219 // Emit the abbreviations data. 2220 Abbrev->Emit(Asm); 2221 } 2222 2223 // Mark end of abbreviations. 2224 Asm->EmitULEB128(0, "EOM(3)"); 2225 2226 MCSymbol *End = Asm->GetTempSymbol(Section->getLabelEndName()); 2227 Asm->OutStreamer.EmitLabel(End); 2228 } 2229 } 2230 2231 // Emit the last address of the section and the end of the line matrix. 2232 void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) { 2233 // Define last address of section. 2234 Asm->OutStreamer.AddComment("Extended Op"); 2235 Asm->EmitInt8(0); 2236 2237 Asm->OutStreamer.AddComment("Op size"); 2238 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1); 2239 Asm->OutStreamer.AddComment("DW_LNE_set_address"); 2240 Asm->EmitInt8(dwarf::DW_LNE_set_address); 2241 2242 Asm->OutStreamer.AddComment("Section end label"); 2243 2244 Asm->OutStreamer.EmitSymbolValue(Asm->GetTempSymbol("section_end",SectionEnd), 2245 Asm->getDataLayout().getPointerSize()); 2246 2247 // Mark end of matrix. 2248 Asm->OutStreamer.AddComment("DW_LNE_end_sequence"); 2249 Asm->EmitInt8(0); 2250 Asm->EmitInt8(1); 2251 Asm->EmitInt8(1); 2252 } 2253 2254 // Emit visible names into a hashed accelerator table section. 2255 void DwarfDebug::emitAccelNames() { 2256 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2257 dwarf::DW_FORM_data4)); 2258 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2259 E = CUMap.end(); I != E; ++I) { 2260 CompileUnit *TheCU = I->second; 2261 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelNames(); 2262 for (StringMap<std::vector<DIE*> >::const_iterator 2263 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2264 StringRef Name = GI->getKey(); 2265 const std::vector<DIE *> &Entities = GI->second; 2266 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2267 DE = Entities.end(); DI != DE; ++DI) 2268 AT.AddName(Name, (*DI)); 2269 } 2270 } 2271 2272 AT.FinalizeTable(Asm, "Names"); 2273 Asm->OutStreamer.SwitchSection( 2274 Asm->getObjFileLowering().getDwarfAccelNamesSection()); 2275 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin"); 2276 Asm->OutStreamer.EmitLabel(SectionBegin); 2277 2278 // Emit the full data. 2279 AT.Emit(Asm, SectionBegin, &InfoHolder); 2280 } 2281 2282 // Emit objective C classes and categories into a hashed accelerator table 2283 // section. 2284 void DwarfDebug::emitAccelObjC() { 2285 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2286 dwarf::DW_FORM_data4)); 2287 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2288 E = CUMap.end(); I != E; ++I) { 2289 CompileUnit *TheCU = I->second; 2290 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelObjC(); 2291 for (StringMap<std::vector<DIE*> >::const_iterator 2292 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2293 StringRef Name = GI->getKey(); 2294 const std::vector<DIE *> &Entities = GI->second; 2295 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2296 DE = Entities.end(); DI != DE; ++DI) 2297 AT.AddName(Name, (*DI)); 2298 } 2299 } 2300 2301 AT.FinalizeTable(Asm, "ObjC"); 2302 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2303 .getDwarfAccelObjCSection()); 2304 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin"); 2305 Asm->OutStreamer.EmitLabel(SectionBegin); 2306 2307 // Emit the full data. 2308 AT.Emit(Asm, SectionBegin, &InfoHolder); 2309 } 2310 2311 // Emit namespace dies into a hashed accelerator table. 2312 void DwarfDebug::emitAccelNamespaces() { 2313 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2314 dwarf::DW_FORM_data4)); 2315 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2316 E = CUMap.end(); I != E; ++I) { 2317 CompileUnit *TheCU = I->second; 2318 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelNamespace(); 2319 for (StringMap<std::vector<DIE*> >::const_iterator 2320 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2321 StringRef Name = GI->getKey(); 2322 const std::vector<DIE *> &Entities = GI->second; 2323 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2324 DE = Entities.end(); DI != DE; ++DI) 2325 AT.AddName(Name, (*DI)); 2326 } 2327 } 2328 2329 AT.FinalizeTable(Asm, "namespac"); 2330 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2331 .getDwarfAccelNamespaceSection()); 2332 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin"); 2333 Asm->OutStreamer.EmitLabel(SectionBegin); 2334 2335 // Emit the full data. 2336 AT.Emit(Asm, SectionBegin, &InfoHolder); 2337 } 2338 2339 // Emit type dies into a hashed accelerator table. 2340 void DwarfDebug::emitAccelTypes() { 2341 std::vector<DwarfAccelTable::Atom> Atoms; 2342 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2343 dwarf::DW_FORM_data4)); 2344 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, 2345 dwarf::DW_FORM_data2)); 2346 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, 2347 dwarf::DW_FORM_data1)); 2348 DwarfAccelTable AT(Atoms); 2349 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2350 E = CUMap.end(); I != E; ++I) { 2351 CompileUnit *TheCU = I->second; 2352 const StringMap<std::vector<std::pair<DIE*, unsigned > > > &Names 2353 = TheCU->getAccelTypes(); 2354 for (StringMap<std::vector<std::pair<DIE*, unsigned> > >::const_iterator 2355 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2356 StringRef Name = GI->getKey(); 2357 const std::vector<std::pair<DIE *, unsigned> > &Entities = GI->second; 2358 for (std::vector<std::pair<DIE *, unsigned> >::const_iterator DI 2359 = Entities.begin(), DE = Entities.end(); DI !=DE; ++DI) 2360 AT.AddName(Name, (*DI).first, (*DI).second); 2361 } 2362 } 2363 2364 AT.FinalizeTable(Asm, "types"); 2365 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2366 .getDwarfAccelTypesSection()); 2367 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin"); 2368 Asm->OutStreamer.EmitLabel(SectionBegin); 2369 2370 // Emit the full data. 2371 AT.Emit(Asm, SectionBegin, &InfoHolder); 2372 } 2373 2374 // Public name handling. 2375 // The format for the various pubnames: 2376 // 2377 // dwarf pubnames - offset/name pairs where the offset is the offset into the CU 2378 // for the DIE that is named. 2379 // 2380 // gnu pubnames - offset/index value/name tuples where the offset is the offset 2381 // into the CU and the index value is computed according to the type of value 2382 // for the DIE that is named. 2383 // 2384 // For type units the offset is the offset of the skeleton DIE. For split dwarf 2385 // it's the offset within the debug_info/debug_types dwo section, however, the 2386 // reference in the pubname header doesn't change. 2387 2388 /// computeIndexValue - Compute the gdb index value for the DIE and CU. 2389 static dwarf::PubIndexEntryDescriptor computeIndexValue(CompileUnit *CU, 2390 DIE *Die) { 2391 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC; 2392 2393 // We could have a specification DIE that has our most of our knowledge, 2394 // look for that now. 2395 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification); 2396 if (SpecVal) { 2397 DIE *SpecDIE = cast<DIEEntry>(SpecVal)->getEntry(); 2398 if (SpecDIE->findAttribute(dwarf::DW_AT_external)) 2399 Linkage = dwarf::GIEL_EXTERNAL; 2400 } else if (Die->findAttribute(dwarf::DW_AT_external)) 2401 Linkage = dwarf::GIEL_EXTERNAL; 2402 2403 switch (Die->getTag()) { 2404 case dwarf::DW_TAG_class_type: 2405 case dwarf::DW_TAG_structure_type: 2406 case dwarf::DW_TAG_union_type: 2407 case dwarf::DW_TAG_enumeration_type: 2408 return dwarf::PubIndexEntryDescriptor( 2409 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus 2410 ? dwarf::GIEL_STATIC 2411 : dwarf::GIEL_EXTERNAL); 2412 case dwarf::DW_TAG_typedef: 2413 case dwarf::DW_TAG_base_type: 2414 case dwarf::DW_TAG_subrange_type: 2415 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC); 2416 case dwarf::DW_TAG_namespace: 2417 return dwarf::GIEK_TYPE; 2418 case dwarf::DW_TAG_subprogram: 2419 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage); 2420 case dwarf::DW_TAG_constant: 2421 case dwarf::DW_TAG_variable: 2422 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage); 2423 case dwarf::DW_TAG_enumerator: 2424 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, 2425 dwarf::GIEL_STATIC); 2426 default: 2427 return dwarf::GIEK_NONE; 2428 } 2429 } 2430 2431 /// emitDebugPubNames - Emit visible names into a debug pubnames section. 2432 /// 2433 void DwarfDebug::emitDebugPubNames(bool GnuStyle) { 2434 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2435 const MCSection *PSec = 2436 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection() 2437 : Asm->getObjFileLowering().getDwarfPubNamesSection(); 2438 2439 typedef DenseMap<const MDNode*, CompileUnit*> CUMapType; 2440 for (CUMapType::iterator I = CUMap.begin(), E = CUMap.end(); I != E; ++I) { 2441 CompileUnit *TheCU = I->second; 2442 unsigned ID = TheCU->getUniqueID(); 2443 2444 // Start the dwarf pubnames section. 2445 Asm->OutStreamer.SwitchSection(PSec); 2446 2447 // Emit a label so we can reference the beginning of this pubname section. 2448 if (GnuStyle) 2449 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("gnu_pubnames", 2450 TheCU->getUniqueID())); 2451 2452 // Emit the header. 2453 Asm->OutStreamer.AddComment("Length of Public Names Info"); 2454 Asm->EmitLabelDifference(Asm->GetTempSymbol("pubnames_end", ID), 2455 Asm->GetTempSymbol("pubnames_begin", ID), 4); 2456 2457 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("pubnames_begin", ID)); 2458 2459 Asm->OutStreamer.AddComment("DWARF Version"); 2460 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION); 2461 2462 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info"); 2463 Asm->EmitSectionOffset(Asm->GetTempSymbol(ISec->getLabelBeginName(), ID), 2464 DwarfInfoSectionSym); 2465 2466 Asm->OutStreamer.AddComment("Compilation Unit Length"); 2467 Asm->EmitLabelDifference(Asm->GetTempSymbol(ISec->getLabelEndName(), ID), 2468 Asm->GetTempSymbol(ISec->getLabelBeginName(), ID), 2469 4); 2470 2471 // Emit the pubnames for this compilation unit. 2472 const StringMap<DIE*> &Globals = TheCU->getGlobalNames(); 2473 for (StringMap<DIE*>::const_iterator 2474 GI = Globals.begin(), GE = Globals.end(); GI != GE; ++GI) { 2475 const char *Name = GI->getKeyData(); 2476 DIE *Entity = GI->second; 2477 2478 Asm->OutStreamer.AddComment("DIE offset"); 2479 Asm->EmitInt32(Entity->getOffset()); 2480 2481 if (GnuStyle) { 2482 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheCU, Entity); 2483 Asm->OutStreamer.AddComment( 2484 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " + 2485 dwarf::GDBIndexEntryLinkageString(Desc.Linkage)); 2486 Asm->EmitInt8(Desc.toBits()); 2487 } 2488 2489 if (Asm->isVerbose()) 2490 Asm->OutStreamer.AddComment("External Name"); 2491 Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength()+1)); 2492 } 2493 2494 Asm->OutStreamer.AddComment("End Mark"); 2495 Asm->EmitInt32(0); 2496 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("pubnames_end", ID)); 2497 } 2498 } 2499 2500 void DwarfDebug::emitDebugPubTypes(bool GnuStyle) { 2501 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2502 const MCSection *PSec = 2503 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection() 2504 : Asm->getObjFileLowering().getDwarfPubTypesSection(); 2505 2506 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2507 E = CUMap.end(); 2508 I != E; ++I) { 2509 CompileUnit *TheCU = I->second; 2510 // Start the dwarf pubtypes section. 2511 Asm->OutStreamer.SwitchSection(PSec); 2512 2513 // Emit a label so we can reference the beginning of this pubtype section. 2514 if (GnuStyle) 2515 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("gnu_pubtypes", 2516 TheCU->getUniqueID())); 2517 2518 // Emit the header. 2519 Asm->OutStreamer.AddComment("Length of Public Types Info"); 2520 Asm->EmitLabelDifference( 2521 Asm->GetTempSymbol("pubtypes_end", TheCU->getUniqueID()), 2522 Asm->GetTempSymbol("pubtypes_begin", TheCU->getUniqueID()), 4); 2523 2524 Asm->OutStreamer.EmitLabel( 2525 Asm->GetTempSymbol("pubtypes_begin", TheCU->getUniqueID())); 2526 2527 if (Asm->isVerbose()) 2528 Asm->OutStreamer.AddComment("DWARF Version"); 2529 Asm->EmitInt16(dwarf::DW_PUBTYPES_VERSION); 2530 2531 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info"); 2532 Asm->EmitSectionOffset( 2533 Asm->GetTempSymbol(ISec->getLabelBeginName(), TheCU->getUniqueID()), 2534 DwarfInfoSectionSym); 2535 2536 Asm->OutStreamer.AddComment("Compilation Unit Length"); 2537 Asm->EmitLabelDifference( 2538 Asm->GetTempSymbol(ISec->getLabelEndName(), TheCU->getUniqueID()), 2539 Asm->GetTempSymbol(ISec->getLabelBeginName(), TheCU->getUniqueID()), 4); 2540 2541 // Emit the pubtypes. 2542 const StringMap<DIE *> &Globals = TheCU->getGlobalTypes(); 2543 for (StringMap<DIE *>::const_iterator GI = Globals.begin(), 2544 GE = Globals.end(); 2545 GI != GE; ++GI) { 2546 const char *Name = GI->getKeyData(); 2547 DIE *Entity = GI->second; 2548 2549 if (Asm->isVerbose()) 2550 Asm->OutStreamer.AddComment("DIE offset"); 2551 Asm->EmitInt32(Entity->getOffset()); 2552 2553 if (GnuStyle) { 2554 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheCU, Entity); 2555 Asm->OutStreamer.AddComment( 2556 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " + 2557 dwarf::GDBIndexEntryLinkageString(Desc.Linkage)); 2558 Asm->EmitInt8(Desc.toBits()); 2559 } 2560 2561 if (Asm->isVerbose()) 2562 Asm->OutStreamer.AddComment("External Name"); 2563 2564 // Emit the name with a terminating null byte. 2565 Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength() + 1)); 2566 } 2567 2568 Asm->OutStreamer.AddComment("End Mark"); 2569 Asm->EmitInt32(0); 2570 Asm->OutStreamer.EmitLabel( 2571 Asm->GetTempSymbol("pubtypes_end", TheCU->getUniqueID())); 2572 } 2573 } 2574 2575 // Emit strings into a string section. 2576 void DwarfUnits::emitStrings(const MCSection *StrSection, 2577 const MCSection *OffsetSection = NULL, 2578 const MCSymbol *StrSecSym = NULL) { 2579 2580 if (StringPool.empty()) return; 2581 2582 // Start the dwarf str section. 2583 Asm->OutStreamer.SwitchSection(StrSection); 2584 2585 // Get all of the string pool entries and put them in an array by their ID so 2586 // we can sort them. 2587 SmallVector<std::pair<unsigned, 2588 StringMapEntry<std::pair<MCSymbol*, unsigned> >*>, 64> Entries; 2589 2590 for (StringMap<std::pair<MCSymbol*, unsigned> >::iterator 2591 I = StringPool.begin(), E = StringPool.end(); 2592 I != E; ++I) 2593 Entries.push_back(std::make_pair(I->second.second, &*I)); 2594 2595 array_pod_sort(Entries.begin(), Entries.end()); 2596 2597 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2598 // Emit a label for reference from debug information entries. 2599 Asm->OutStreamer.EmitLabel(Entries[i].second->getValue().first); 2600 2601 // Emit the string itself with a terminating null byte. 2602 Asm->OutStreamer.EmitBytes(StringRef(Entries[i].second->getKeyData(), 2603 Entries[i].second->getKeyLength()+1)); 2604 } 2605 2606 // If we've got an offset section go ahead and emit that now as well. 2607 if (OffsetSection) { 2608 Asm->OutStreamer.SwitchSection(OffsetSection); 2609 unsigned offset = 0; 2610 unsigned size = 4; // FIXME: DWARF64 is 8. 2611 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2612 Asm->OutStreamer.EmitIntValue(offset, size); 2613 offset += Entries[i].second->getKeyLength() + 1; 2614 } 2615 } 2616 } 2617 2618 // Emit strings into a string section. 2619 void DwarfUnits::emitAddresses(const MCSection *AddrSection) { 2620 2621 if (AddressPool.empty()) return; 2622 2623 // Start the dwarf addr section. 2624 Asm->OutStreamer.SwitchSection(AddrSection); 2625 2626 // Order the address pool entries by ID 2627 SmallVector<const MCExpr *, 64> Entries(AddressPool.size()); 2628 2629 for (DenseMap<const MCExpr *, unsigned>::iterator I = AddressPool.begin(), 2630 E = AddressPool.end(); 2631 I != E; ++I) 2632 Entries[I->second] = I->first; 2633 2634 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2635 // Emit an expression for reference from debug information entries. 2636 if (const MCExpr *Expr = Entries[i]) 2637 Asm->OutStreamer.EmitValue(Expr, Asm->getDataLayout().getPointerSize()); 2638 else 2639 Asm->OutStreamer.EmitIntValue(0, Asm->getDataLayout().getPointerSize()); 2640 } 2641 2642 } 2643 2644 // Emit visible names into a debug str section. 2645 void DwarfDebug::emitDebugStr() { 2646 DwarfUnits &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; 2647 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection()); 2648 } 2649 2650 // Emit locations into the debug loc section. 2651 void DwarfDebug::emitDebugLoc() { 2652 if (DotDebugLocEntries.empty()) 2653 return; 2654 2655 for (SmallVectorImpl<DotDebugLocEntry>::iterator 2656 I = DotDebugLocEntries.begin(), E = DotDebugLocEntries.end(); 2657 I != E; ++I) { 2658 DotDebugLocEntry &Entry = *I; 2659 if (I + 1 != DotDebugLocEntries.end()) 2660 Entry.Merge(I+1); 2661 } 2662 2663 // Start the dwarf loc section. 2664 Asm->OutStreamer.SwitchSection( 2665 Asm->getObjFileLowering().getDwarfLocSection()); 2666 unsigned char Size = Asm->getDataLayout().getPointerSize(); 2667 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", 0)); 2668 unsigned index = 1; 2669 for (SmallVectorImpl<DotDebugLocEntry>::iterator 2670 I = DotDebugLocEntries.begin(), E = DotDebugLocEntries.end(); 2671 I != E; ++I, ++index) { 2672 DotDebugLocEntry &Entry = *I; 2673 if (Entry.isMerged()) continue; 2674 if (Entry.isEmpty()) { 2675 Asm->OutStreamer.EmitIntValue(0, Size); 2676 Asm->OutStreamer.EmitIntValue(0, Size); 2677 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", index)); 2678 } else { 2679 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size); 2680 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size); 2681 DIVariable DV(Entry.getVariable()); 2682 Asm->OutStreamer.AddComment("Loc expr size"); 2683 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol(); 2684 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol(); 2685 Asm->EmitLabelDifference(end, begin, 2); 2686 Asm->OutStreamer.EmitLabel(begin); 2687 if (Entry.isInt()) { 2688 DIBasicType BTy(DV.getType()); 2689 if (BTy.Verify() && 2690 (BTy.getEncoding() == dwarf::DW_ATE_signed 2691 || BTy.getEncoding() == dwarf::DW_ATE_signed_char)) { 2692 Asm->OutStreamer.AddComment("DW_OP_consts"); 2693 Asm->EmitInt8(dwarf::DW_OP_consts); 2694 Asm->EmitSLEB128(Entry.getInt()); 2695 } else { 2696 Asm->OutStreamer.AddComment("DW_OP_constu"); 2697 Asm->EmitInt8(dwarf::DW_OP_constu); 2698 Asm->EmitULEB128(Entry.getInt()); 2699 } 2700 } else if (Entry.isLocation()) { 2701 MachineLocation Loc = Entry.getLoc(); 2702 if (!DV.hasComplexAddress()) 2703 // Regular entry. 2704 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2705 else { 2706 // Complex address entry. 2707 unsigned N = DV.getNumAddrElements(); 2708 unsigned i = 0; 2709 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) { 2710 if (Loc.getOffset()) { 2711 i = 2; 2712 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2713 Asm->OutStreamer.AddComment("DW_OP_deref"); 2714 Asm->EmitInt8(dwarf::DW_OP_deref); 2715 Asm->OutStreamer.AddComment("DW_OP_plus_uconst"); 2716 Asm->EmitInt8(dwarf::DW_OP_plus_uconst); 2717 Asm->EmitSLEB128(DV.getAddrElement(1)); 2718 } else { 2719 // If first address element is OpPlus then emit 2720 // DW_OP_breg + Offset instead of DW_OP_reg + Offset. 2721 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1)); 2722 Asm->EmitDwarfRegOp(TLoc, DV.isIndirect()); 2723 i = 2; 2724 } 2725 } else { 2726 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2727 } 2728 2729 // Emit remaining complex address elements. 2730 for (; i < N; ++i) { 2731 uint64_t Element = DV.getAddrElement(i); 2732 if (Element == DIBuilder::OpPlus) { 2733 Asm->EmitInt8(dwarf::DW_OP_plus_uconst); 2734 Asm->EmitULEB128(DV.getAddrElement(++i)); 2735 } else if (Element == DIBuilder::OpDeref) { 2736 if (!Loc.isReg()) 2737 Asm->EmitInt8(dwarf::DW_OP_deref); 2738 } else 2739 llvm_unreachable("unknown Opcode found in complex address"); 2740 } 2741 } 2742 } 2743 // else ... ignore constant fp. There is not any good way to 2744 // to represent them here in dwarf. 2745 Asm->OutStreamer.EmitLabel(end); 2746 } 2747 } 2748 } 2749 2750 struct SymbolCUSorter { 2751 SymbolCUSorter(const MCStreamer &s) : Streamer(s) {} 2752 const MCStreamer &Streamer; 2753 2754 bool operator() (const SymbolCU &A, const SymbolCU &B) { 2755 unsigned IA = A.Sym ? Streamer.GetSymbolOrder(A.Sym) : 0; 2756 unsigned IB = B.Sym ? Streamer.GetSymbolOrder(B.Sym) : 0; 2757 2758 // Symbols with no order assigned should be placed at the end. 2759 // (e.g. section end labels) 2760 if (IA == 0) 2761 IA = (unsigned)(-1); 2762 if (IB == 0) 2763 IB = (unsigned)(-1); 2764 return IA < IB; 2765 } 2766 }; 2767 2768 static bool CUSort(const CompileUnit *A, const CompileUnit *B) { 2769 return (A->getUniqueID() < B->getUniqueID()); 2770 } 2771 2772 struct ArangeSpan { 2773 const MCSymbol *Start, *End; 2774 }; 2775 2776 // Emit a debug aranges section, containing a CU lookup for any 2777 // address we can tie back to a CU. 2778 void DwarfDebug::emitDebugARanges() { 2779 // Start the dwarf aranges section. 2780 Asm->OutStreamer 2781 .SwitchSection(Asm->getObjFileLowering().getDwarfARangesSection()); 2782 2783 typedef DenseMap<CompileUnit *, std::vector<ArangeSpan> > SpansType; 2784 2785 SpansType Spans; 2786 2787 // Build a list of sections used. 2788 std::vector<const MCSection *> Sections; 2789 for (SectionMapType::iterator it = SectionMap.begin(); it != SectionMap.end(); 2790 it++) { 2791 const MCSection *Section = it->first; 2792 Sections.push_back(Section); 2793 } 2794 2795 // Sort the sections into order. 2796 // This is only done to ensure consistent output order across different runs. 2797 std::sort(Sections.begin(), Sections.end(), SectionSort); 2798 2799 // Build a set of address spans, sorted by CU. 2800 for (size_t SecIdx=0;SecIdx<Sections.size();SecIdx++) { 2801 const MCSection *Section = Sections[SecIdx]; 2802 SmallVector<SymbolCU, 8> &List = SectionMap[Section]; 2803 if (List.size() < 2) 2804 continue; 2805 2806 // Sort the symbols by offset within the section. 2807 SymbolCUSorter sorter(Asm->OutStreamer); 2808 std::sort(List.begin(), List.end(), sorter); 2809 2810 // If we have no section (e.g. common), just write out 2811 // individual spans for each symbol. 2812 if (Section == NULL) { 2813 for (size_t n = 0; n < List.size(); n++) { 2814 const SymbolCU &Cur = List[n]; 2815 2816 ArangeSpan Span; 2817 Span.Start = Cur.Sym; 2818 Span.End = NULL; 2819 if (Cur.CU) 2820 Spans[Cur.CU].push_back(Span); 2821 } 2822 } else { 2823 // Build spans between each label. 2824 const MCSymbol *StartSym = List[0].Sym; 2825 for (size_t n = 1; n < List.size(); n++) { 2826 const SymbolCU &Prev = List[n - 1]; 2827 const SymbolCU &Cur = List[n]; 2828 2829 // Try and build the longest span we can within the same CU. 2830 if (Cur.CU != Prev.CU) { 2831 ArangeSpan Span; 2832 Span.Start = StartSym; 2833 Span.End = Cur.Sym; 2834 Spans[Prev.CU].push_back(Span); 2835 StartSym = Cur.Sym; 2836 } 2837 } 2838 } 2839 } 2840 2841 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2842 unsigned PtrSize = Asm->getDataLayout().getPointerSize(); 2843 2844 // Build a list of CUs used. 2845 std::vector<CompileUnit *> CUs; 2846 for (SpansType::iterator it = Spans.begin(); it != Spans.end(); it++) { 2847 CompileUnit *CU = it->first; 2848 CUs.push_back(CU); 2849 } 2850 2851 // Sort the CU list (again, to ensure consistent output order). 2852 std::sort(CUs.begin(), CUs.end(), CUSort); 2853 2854 // Emit an arange table for each CU we used. 2855 for (size_t CUIdx=0;CUIdx<CUs.size();CUIdx++) { 2856 CompileUnit *CU = CUs[CUIdx]; 2857 std::vector<ArangeSpan> &List = Spans[CU]; 2858 2859 // Emit size of content not including length itself. 2860 unsigned ContentSize 2861 = sizeof(int16_t) // DWARF ARange version number 2862 + sizeof(int32_t) // Offset of CU in the .debug_info section 2863 + sizeof(int8_t) // Pointer Size (in bytes) 2864 + sizeof(int8_t); // Segment Size (in bytes) 2865 2866 unsigned TupleSize = PtrSize * 2; 2867 2868 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple. 2869 unsigned Padding = 0; 2870 while (((sizeof(int32_t) + ContentSize + Padding) % TupleSize) != 0) 2871 Padding++; 2872 2873 ContentSize += Padding; 2874 ContentSize += (List.size() + 1) * TupleSize; 2875 2876 // For each compile unit, write the list of spans it covers. 2877 Asm->OutStreamer.AddComment("Length of ARange Set"); 2878 Asm->EmitInt32(ContentSize); 2879 Asm->OutStreamer.AddComment("DWARF Arange version number"); 2880 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION); 2881 Asm->OutStreamer.AddComment("Offset Into Debug Info Section"); 2882 Asm->EmitSectionOffset( 2883 Asm->GetTempSymbol(ISec->getLabelBeginName(), CU->getUniqueID()), 2884 DwarfInfoSectionSym); 2885 Asm->OutStreamer.AddComment("Address Size (in bytes)"); 2886 Asm->EmitInt8(PtrSize); 2887 Asm->OutStreamer.AddComment("Segment Size (in bytes)"); 2888 Asm->EmitInt8(0); 2889 2890 for (unsigned n = 0; n < Padding; n++) 2891 Asm->EmitInt8(0xff); 2892 2893 for (unsigned n = 0; n < List.size(); n++) { 2894 const ArangeSpan &Span = List[n]; 2895 Asm->EmitLabelReference(Span.Start, PtrSize); 2896 2897 // Calculate the size as being from the span start to it's end. 2898 if (Span.End) { 2899 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize); 2900 } else { 2901 // For symbols without an end marker (e.g. common), we 2902 // write a single arange entry containing just that one symbol. 2903 uint64_t Size = SymSize[Span.Start]; 2904 if (Size == 0) 2905 Size = 1; 2906 2907 Asm->OutStreamer.EmitIntValue(Size, PtrSize); 2908 } 2909 } 2910 2911 Asm->OutStreamer.AddComment("ARange terminator"); 2912 Asm->OutStreamer.EmitIntValue(0, PtrSize); 2913 Asm->OutStreamer.EmitIntValue(0, PtrSize); 2914 } 2915 } 2916 2917 // Emit visible names into a debug ranges section. 2918 void DwarfDebug::emitDebugRanges() { 2919 // Start the dwarf ranges section. 2920 Asm->OutStreamer 2921 .SwitchSection(Asm->getObjFileLowering().getDwarfRangesSection()); 2922 unsigned char Size = Asm->getDataLayout().getPointerSize(); 2923 for (SmallVectorImpl<const MCSymbol *>::iterator 2924 I = DebugRangeSymbols.begin(), E = DebugRangeSymbols.end(); 2925 I != E; ++I) { 2926 if (*I) 2927 Asm->OutStreamer.EmitSymbolValue(const_cast<MCSymbol*>(*I), Size); 2928 else 2929 Asm->OutStreamer.EmitIntValue(0, Size); 2930 } 2931 } 2932 2933 // Emit visible names into a debug macinfo section. 2934 void DwarfDebug::emitDebugMacInfo() { 2935 if (const MCSection *LineInfo = 2936 Asm->getObjFileLowering().getDwarfMacroInfoSection()) { 2937 // Start the dwarf macinfo section. 2938 Asm->OutStreamer.SwitchSection(LineInfo); 2939 } 2940 } 2941 2942 // DWARF5 Experimental Separate Dwarf emitters. 2943 2944 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list, 2945 // DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id, 2946 // DW_AT_ranges_base, DW_AT_addr_base. 2947 CompileUnit *DwarfDebug::constructSkeletonCU(const CompileUnit *CU) { 2948 2949 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit); 2950 CompileUnit *NewCU = new CompileUnit(CU->getUniqueID(), Die, CU->getNode(), 2951 Asm, this, &SkeletonHolder); 2952 2953 NewCU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name, 2954 CU->getNode().getSplitDebugFilename()); 2955 2956 // Relocate to the beginning of the addr_base section, else 0 for the 2957 // beginning of the one for this compile unit. 2958 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2959 NewCU->addLabel(Die, dwarf::DW_AT_GNU_addr_base, dwarf::DW_FORM_sec_offset, 2960 DwarfAddrSectionSym); 2961 else 2962 NewCU->addUInt(Die, dwarf::DW_AT_GNU_addr_base, 2963 dwarf::DW_FORM_sec_offset, 0); 2964 2965 // 2.17.1 requires that we use DW_AT_low_pc for a single entry point 2966 // into an entity. We're using 0, or a NULL label for this. 2967 NewCU->addUInt(Die, dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr, 0); 2968 2969 // DW_AT_stmt_list is a offset of line number information for this 2970 // compile unit in debug_line section. 2971 // FIXME: Should handle multiple compile units. 2972 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2973 NewCU->addLabel(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 2974 DwarfLineSectionSym); 2975 else 2976 NewCU->addUInt(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 0); 2977 2978 if (!CompilationDir.empty()) 2979 NewCU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir); 2980 2981 // Flags to let the linker know we have emitted new style pubnames. 2982 if (GenerateGnuPubSections) { 2983 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2984 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_sec_offset, 2985 Asm->GetTempSymbol("gnu_pubnames", NewCU->getUniqueID())); 2986 else 2987 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_data4, 2988 Asm->GetTempSymbol("gnu_pubnames", NewCU->getUniqueID()), 2989 DwarfGnuPubNamesSectionSym); 2990 2991 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2992 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_sec_offset, 2993 Asm->GetTempSymbol("gnu_pubtypes", NewCU->getUniqueID())); 2994 else 2995 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_data4, 2996 Asm->GetTempSymbol("gnu_pubtypes", NewCU->getUniqueID()), 2997 DwarfGnuPubTypesSectionSym); 2998 } 2999 3000 // Flag if we've emitted any ranges and their location for the compile unit. 3001 if (DebugRangeSymbols.size()) { 3002 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 3003 NewCU->addLabel(Die, dwarf::DW_AT_GNU_ranges_base, 3004 dwarf::DW_FORM_sec_offset, DwarfDebugRangeSectionSym); 3005 else 3006 NewCU->addUInt(Die, dwarf::DW_AT_GNU_ranges_base, dwarf::DW_FORM_data4, 3007 0); 3008 } 3009 3010 SkeletonHolder.addUnit(NewCU); 3011 SkeletonCUs.push_back(NewCU); 3012 3013 return NewCU; 3014 } 3015 3016 void DwarfDebug::emitSkeletonAbbrevs(const MCSection *Section) { 3017 assert(useSplitDwarf() && "No split dwarf debug info?"); 3018 emitAbbrevs(Section, &SkeletonAbbrevs); 3019 } 3020 3021 // Emit the .debug_info.dwo section for separated dwarf. This contains the 3022 // compile units that would normally be in debug_info. 3023 void DwarfDebug::emitDebugInfoDWO() { 3024 assert(useSplitDwarf() && "No split dwarf debug info?"); 3025 InfoHolder.emitUnits(this, Asm->getObjFileLowering().getDwarfInfoDWOSection(), 3026 Asm->getObjFileLowering().getDwarfAbbrevDWOSection(), 3027 DwarfAbbrevDWOSectionSym); 3028 } 3029 3030 // Emit the .debug_abbrev.dwo section for separated dwarf. This contains the 3031 // abbreviations for the .debug_info.dwo section. 3032 void DwarfDebug::emitDebugAbbrevDWO() { 3033 assert(useSplitDwarf() && "No split dwarf?"); 3034 emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection(), 3035 &Abbreviations); 3036 } 3037 3038 // Emit the .debug_str.dwo section for separated dwarf. This contains the 3039 // string section and is identical in format to traditional .debug_str 3040 // sections. 3041 void DwarfDebug::emitDebugStrDWO() { 3042 assert(useSplitDwarf() && "No split dwarf?"); 3043 const MCSection *OffSec = Asm->getObjFileLowering() 3044 .getDwarfStrOffDWOSection(); 3045 const MCSymbol *StrSym = DwarfStrSectionSym; 3046 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(), 3047 OffSec, StrSym); 3048 } 3049