DwarfDebug.cpp revision c622824ccbb74ac726c656ebc98647810d152cce
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" 50using namespace llvm; 51 52static cl::opt<bool> 53DisableDebugInfoPrinting("disable-debug-info-print", cl::Hidden, 54 cl::desc("Disable debug info printing")); 55 56static 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 61static cl::opt<bool> 62GenerateODRHash("generate-odr-hash", cl::Hidden, 63 cl::desc("Add an ODR hash to external type DIEs."), 64 cl::init(false)); 65 66static cl::opt<bool> 67GenerateCUHash("generate-cu-hash", cl::Hidden, 68 cl::desc("Add the CU hash as the dwo_id."), 69 cl::init(false)); 70 71static cl::opt<bool> 72GenerateGnuPubSections("generate-gnu-dwarf-pub-sections", cl::Hidden, 73 cl::desc("Generate GNU-style pubnames and pubtypes"), 74 cl::init(false)); 75 76namespace { 77enum DefaultOnOff { 78 Default, 79 Enable, 80 Disable 81}; 82} 83 84static cl::opt<DefaultOnOff> 85DwarfAccelTables("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 92static cl::opt<DefaultOnOff> 93SplitDwarf("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 100static cl::opt<DefaultOnOff> 101DwarfPubSections("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 108static const char *const DWARFGroupName = "DWARF Emission"; 109static const char *const DbgTimerName = "DWARF Debug Writer"; 110 111//===----------------------------------------------------------------------===// 112 113// Configuration values for initial hash set sizes (log2). 114// 115static const unsigned InitAbbreviationsSetSize = 9; // log2(512) 116 117namespace llvm { 118 119/// resolve - Look in the DwarfDebug map for the MDNode that 120/// corresponds to the reference. 121template <typename T> 122T DbgVariable::resolve(DIRef<T> Ref) const { 123 return DD->resolve(Ref); 124} 125 126DIType 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 = DIDerivedType(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. 174static 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 181DwarfDebug::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. 228static 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 238MCSymbol *DwarfUnits::getStringPoolSym() { 239 return Asm->GetTempSymbol(StringPref); 240} 241 242MCSymbol *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 251unsigned 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 261unsigned DwarfUnits::getAddrPoolIndex(const MCSymbol *Sym) { 262 return getAddrPoolIndex(MCSymbolRefExpr::Create(Sym, Asm->OutContext)); 263} 264 265unsigned 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// 275void 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 292static bool isObjCClass(StringRef Name) { 293 return Name.startswith("+") || Name.startswith("-"); 294} 295 296static bool hasObjCCategory(StringRef Name) { 297 if (!isObjCClass(Name)) return false; 298 299 return Name.find(") ") != StringRef::npos; 300} 301 302static 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 315static 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. 320static 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. 330static 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. 355bool 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. 369DIE *DwarfDebug::updateSubprogramScopeDIE(CompileUnit *SPCU, 370 const MDNode *SPNode) { 371 DIE *SPDie = SPCU->getDIE(SPNode); 372 373 assert(SPDie && "Unable to find subprogram DIE!"); 374 DISubprogram SP(SPNode); 375 376 // If we're updating an abstract DIE, then we will be adding the children and 377 // object pointer later on. But what we don't want to do is process the 378 // concrete DIE twice. 379 if (DIE *AbsSPDIE = AbstractSPDies.lookup(SPNode)) { 380 // Pick up abstract subprogram DIE. 381 SPDie = new DIE(dwarf::DW_TAG_subprogram); 382 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_abstract_origin, AbsSPDIE); 383 SPCU->addDie(SPDie); 384 } else { 385 DISubprogram SPDecl = SP.getFunctionDeclaration(); 386 if (!SPDecl.isSubprogram()) { 387 // There is not any need to generate specification DIE for a function 388 // defined at compile unit level. If a function is defined inside another 389 // function then gdb prefers the definition at top level and but does not 390 // expect specification DIE in parent function. So avoid creating 391 // specification DIE for a function defined inside a function. 392 DIScope SPContext = resolve(SP.getContext()); 393 if (SP.isDefinition() && !SPContext.isCompileUnit() && 394 !SPContext.isFile() && 395 !isSubprogramContext(SPContext)) { 396 SPCU->addFlag(SPDie, dwarf::DW_AT_declaration); 397 398 // Add arguments. 399 DICompositeType SPTy = SP.getType(); 400 DIArray Args = SPTy.getTypeArray(); 401 uint16_t SPTag = SPTy.getTag(); 402 if (SPTag == dwarf::DW_TAG_subroutine_type) 403 for (unsigned i = 1, N = Args.getNumElements(); i < N; ++i) { 404 DIE *Arg = new DIE(dwarf::DW_TAG_formal_parameter); 405 DIType ATy = DIType(Args.getElement(i)); 406 SPCU->addType(Arg, ATy); 407 if (ATy.isArtificial()) 408 SPCU->addFlag(Arg, dwarf::DW_AT_artificial); 409 if (ATy.isObjectPointer()) 410 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_object_pointer, Arg); 411 SPDie->addChild(Arg); 412 } 413 DIE *SPDeclDie = SPDie; 414 SPDie = new DIE(dwarf::DW_TAG_subprogram); 415 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_specification, SPDeclDie); 416 SPCU->addDie(SPDie); 417 } 418 } 419 } 420 421 SPCU->addLabelAddress(SPDie, dwarf::DW_AT_low_pc, 422 Asm->GetTempSymbol("func_begin", 423 Asm->getFunctionNumber())); 424 SPCU->addLabelAddress(SPDie, dwarf::DW_AT_high_pc, 425 Asm->GetTempSymbol("func_end", 426 Asm->getFunctionNumber())); 427 const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo(); 428 MachineLocation Location(RI->getFrameRegister(*Asm->MF)); 429 SPCU->addAddress(SPDie, dwarf::DW_AT_frame_base, Location); 430 431 // Add name to the name table, we do this here because we're guaranteed 432 // to have concrete versions of our DW_TAG_subprogram nodes. 433 addSubprogramNames(SPCU, SP, SPDie); 434 435 return SPDie; 436} 437 438/// Check whether we should create a DIE for the given Scope, return true 439/// if we don't create a DIE (the corresponding DIE is null). 440bool DwarfDebug::isLexicalScopeDIENull(LexicalScope *Scope) { 441 if (Scope->isAbstractScope()) 442 return false; 443 444 // We don't create a DIE if there is no Range. 445 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 446 if (Ranges.empty()) 447 return true; 448 449 if (Ranges.size() > 1) 450 return false; 451 452 // We don't create a DIE if we have a single Range and the end label 453 // is null. 454 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 455 MCSymbol *End = getLabelAfterInsn(RI->second); 456 return !End; 457} 458 459// Construct new DW_TAG_lexical_block for this scope and attach 460// DW_AT_low_pc/DW_AT_high_pc labels. 461DIE *DwarfDebug::constructLexicalScopeDIE(CompileUnit *TheCU, 462 LexicalScope *Scope) { 463 if (isLexicalScopeDIENull(Scope)) 464 return 0; 465 466 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_lexical_block); 467 if (Scope->isAbstractScope()) 468 return ScopeDIE; 469 470 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 471 // If we have multiple ranges, emit them into the range section. 472 if (Ranges.size() > 1) { 473 // .debug_range section has not been laid out yet. Emit offset in 474 // .debug_range as a uint, size 4, for now. emitDIE will handle 475 // DW_AT_ranges appropriately. 476 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_ranges, dwarf::DW_FORM_data4, 477 DebugRangeSymbols.size() 478 * Asm->getDataLayout().getPointerSize()); 479 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 480 RE = Ranges.end(); RI != RE; ++RI) { 481 DebugRangeSymbols.push_back(getLabelBeforeInsn(RI->first)); 482 DebugRangeSymbols.push_back(getLabelAfterInsn(RI->second)); 483 } 484 485 // Terminate the range list. 486 DebugRangeSymbols.push_back(NULL); 487 DebugRangeSymbols.push_back(NULL); 488 return ScopeDIE; 489 } 490 491 // Construct the address range for this DIE. 492 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 493 MCSymbol *Start = getLabelBeforeInsn(RI->first); 494 MCSymbol *End = getLabelAfterInsn(RI->second); 495 assert(End && "End label should not be null!"); 496 497 assert(Start->isDefined() && "Invalid starting label for an inlined scope!"); 498 assert(End->isDefined() && "Invalid end label for an inlined scope!"); 499 500 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_low_pc, Start); 501 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_high_pc, End); 502 503 return ScopeDIE; 504} 505 506// This scope represents inlined body of a function. Construct DIE to 507// represent this concrete inlined copy of the function. 508DIE *DwarfDebug::constructInlinedScopeDIE(CompileUnit *TheCU, 509 LexicalScope *Scope) { 510 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 511 assert(Ranges.empty() == false && 512 "LexicalScope does not have instruction markers!"); 513 514 if (!Scope->getScopeNode()) 515 return NULL; 516 DIScope DS(Scope->getScopeNode()); 517 DISubprogram InlinedSP = getDISubprogram(DS); 518 DIE *OriginDIE = TheCU->getDIE(InlinedSP); 519 if (!OriginDIE) { 520 DEBUG(dbgs() << "Unable to find original DIE for an inlined subprogram."); 521 return NULL; 522 } 523 524 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_inlined_subroutine); 525 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_abstract_origin, OriginDIE); 526 527 if (Ranges.size() > 1) { 528 // .debug_range section has not been laid out yet. Emit offset in 529 // .debug_range as a uint, size 4, for now. emitDIE will handle 530 // DW_AT_ranges appropriately. 531 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_ranges, dwarf::DW_FORM_data4, 532 DebugRangeSymbols.size() 533 * Asm->getDataLayout().getPointerSize()); 534 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 535 RE = Ranges.end(); RI != RE; ++RI) { 536 DebugRangeSymbols.push_back(getLabelBeforeInsn(RI->first)); 537 DebugRangeSymbols.push_back(getLabelAfterInsn(RI->second)); 538 } 539 DebugRangeSymbols.push_back(NULL); 540 DebugRangeSymbols.push_back(NULL); 541 } else { 542 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 543 MCSymbol *StartLabel = getLabelBeforeInsn(RI->first); 544 MCSymbol *EndLabel = getLabelAfterInsn(RI->second); 545 546 if (StartLabel == 0 || EndLabel == 0) 547 llvm_unreachable("Unexpected Start and End labels for an inlined scope!"); 548 549 assert(StartLabel->isDefined() && 550 "Invalid starting label for an inlined scope!"); 551 assert(EndLabel->isDefined() && "Invalid end label for an inlined scope!"); 552 553 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_low_pc, StartLabel); 554 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_high_pc, EndLabel); 555 } 556 557 InlinedSubprogramDIEs.insert(OriginDIE); 558 559 // Add the call site information to the DIE. 560 DILocation DL(Scope->getInlinedAt()); 561 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_file, 0, 562 getOrCreateSourceID(DL.getFilename(), DL.getDirectory(), 563 TheCU->getUniqueID())); 564 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_line, 0, DL.getLineNumber()); 565 566 // Add name to the name table, we do this here because we're guaranteed 567 // to have concrete versions of our DW_TAG_inlined_subprogram nodes. 568 addSubprogramNames(TheCU, InlinedSP, ScopeDIE); 569 570 return ScopeDIE; 571} 572 573DIE *DwarfDebug::createScopeChildrenDIE(CompileUnit *TheCU, LexicalScope *Scope, 574 SmallVectorImpl<DIE*> &Children) { 575 DIE *ObjectPointer = NULL; 576 577 // Collect arguments for current function. 578 if (LScopes.isCurrentFunctionScope(Scope)) 579 for (unsigned i = 0, N = CurrentFnArguments.size(); i < N; ++i) 580 if (DbgVariable *ArgDV = CurrentFnArguments[i]) 581 if (DIE *Arg = 582 TheCU->constructVariableDIE(ArgDV, Scope->isAbstractScope())) { 583 Children.push_back(Arg); 584 if (ArgDV->isObjectPointer()) ObjectPointer = Arg; 585 } 586 587 // Collect lexical scope children first. 588 const SmallVectorImpl<DbgVariable *> &Variables =ScopeVariables.lookup(Scope); 589 for (unsigned i = 0, N = Variables.size(); i < N; ++i) 590 if (DIE *Variable = 591 TheCU->constructVariableDIE(Variables[i], Scope->isAbstractScope())) { 592 Children.push_back(Variable); 593 if (Variables[i]->isObjectPointer()) ObjectPointer = Variable; 594 } 595 const SmallVectorImpl<LexicalScope *> &Scopes = Scope->getChildren(); 596 for (unsigned j = 0, M = Scopes.size(); j < M; ++j) 597 if (DIE *Nested = constructScopeDIE(TheCU, Scopes[j])) 598 Children.push_back(Nested); 599 return ObjectPointer; 600} 601 602// Construct a DIE for this scope. 603DIE *DwarfDebug::constructScopeDIE(CompileUnit *TheCU, LexicalScope *Scope) { 604 if (!Scope || !Scope->getScopeNode()) 605 return NULL; 606 607 DIScope DS(Scope->getScopeNode()); 608 609 SmallVector<DIE *, 8> Children; 610 DIE *ObjectPointer = NULL; 611 bool ChildrenCreated = false; 612 613 // We try to create the scope DIE first, then the children DIEs. This will 614 // avoid creating un-used children then removing them later when we find out 615 // the scope DIE is null. 616 DIE *ScopeDIE = NULL; 617 if (Scope->getInlinedAt()) 618 ScopeDIE = constructInlinedScopeDIE(TheCU, Scope); 619 else if (DS.isSubprogram()) { 620 ProcessedSPNodes.insert(DS); 621 if (Scope->isAbstractScope()) { 622 ScopeDIE = TheCU->getDIE(DS); 623 // Note down abstract DIE. 624 if (ScopeDIE) 625 AbstractSPDies.insert(std::make_pair(DS, ScopeDIE)); 626 } 627 else 628 ScopeDIE = updateSubprogramScopeDIE(TheCU, DS); 629 } 630 else { 631 // Early exit when we know the scope DIE is going to be null. 632 if (isLexicalScopeDIENull(Scope)) 633 return NULL; 634 635 // We create children here when we know the scope DIE is not going to be 636 // null and the children will be added to the scope DIE. 637 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children); 638 ChildrenCreated = true; 639 640 // There is no need to emit empty lexical block DIE. 641 std::pair<ImportedEntityMap::const_iterator, 642 ImportedEntityMap::const_iterator> Range = std::equal_range( 643 ScopesWithImportedEntities.begin(), ScopesWithImportedEntities.end(), 644 std::pair<const MDNode *, const MDNode *>(DS, (const MDNode*)0), 645 less_first()); 646 if (Children.empty() && Range.first == Range.second) 647 return NULL; 648 ScopeDIE = constructLexicalScopeDIE(TheCU, Scope); 649 assert(ScopeDIE && "Scope DIE should not be null."); 650 for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second; 651 ++i) 652 constructImportedEntityDIE(TheCU, i->second, ScopeDIE); 653 } 654 655 if (!ScopeDIE) { 656 assert(Children.empty() && 657 "We create children only when the scope DIE is not null."); 658 return NULL; 659 } 660 if (!ChildrenCreated) 661 // We create children when the scope DIE is not null. 662 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children); 663 664 // Add children 665 for (SmallVectorImpl<DIE *>::iterator I = Children.begin(), 666 E = Children.end(); I != E; ++I) 667 ScopeDIE->addChild(*I); 668 669 if (DS.isSubprogram() && ObjectPointer != NULL) 670 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, ObjectPointer); 671 672 if (DS.isSubprogram()) 673 TheCU->addPubTypes(DISubprogram(DS)); 674 675 return ScopeDIE; 676} 677 678// Look up the source id with the given directory and source file names. 679// If none currently exists, create a new id and insert it in the 680// SourceIds map. This can update DirectoryNames and SourceFileNames maps 681// as well. 682unsigned DwarfDebug::getOrCreateSourceID(StringRef FileName, 683 StringRef DirName, unsigned CUID) { 684 // If we use .loc in assembly, we can't separate .file entries according to 685 // compile units. Thus all files will belong to the default compile unit. 686 687 // FIXME: add a better feature test than hasRawTextSupport. Even better, 688 // extend .file to support this. 689 if (Asm->TM.hasMCUseLoc() && Asm->OutStreamer.hasRawTextSupport()) 690 CUID = 0; 691 692 // If FE did not provide a file name, then assume stdin. 693 if (FileName.empty()) 694 return getOrCreateSourceID("<stdin>", StringRef(), CUID); 695 696 // TODO: this might not belong here. See if we can factor this better. 697 if (DirName == CompilationDir) 698 DirName = ""; 699 700 // FileIDCUMap stores the current ID for the given compile unit. 701 unsigned SrcId = FileIDCUMap[CUID] + 1; 702 703 // We look up the CUID/file/dir by concatenating them with a zero byte. 704 SmallString<128> NamePair; 705 NamePair += utostr(CUID); 706 NamePair += '\0'; 707 NamePair += DirName; 708 NamePair += '\0'; // Zero bytes are not allowed in paths. 709 NamePair += FileName; 710 711 StringMapEntry<unsigned> &Ent = SourceIdMap.GetOrCreateValue(NamePair, SrcId); 712 if (Ent.getValue() != SrcId) 713 return Ent.getValue(); 714 715 FileIDCUMap[CUID] = SrcId; 716 // Print out a .file directive to specify files for .loc directives. 717 Asm->OutStreamer.EmitDwarfFileDirective(SrcId, DirName, FileName, CUID); 718 719 return SrcId; 720} 721 722// Create new CompileUnit for the given metadata node with tag 723// DW_TAG_compile_unit. 724CompileUnit *DwarfDebug::constructCompileUnit(const MDNode *N) { 725 DICompileUnit DIUnit(N); 726 StringRef FN = DIUnit.getFilename(); 727 CompilationDir = DIUnit.getDirectory(); 728 729 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit); 730 CompileUnit *NewCU = 731 new CompileUnit(GlobalCUIndexCount++, Die, N, Asm, this, &InfoHolder); 732 733 FileIDCUMap[NewCU->getUniqueID()] = 0; 734 // Call this to emit a .file directive if it wasn't emitted for the source 735 // file this CU comes from yet. 736 getOrCreateSourceID(FN, CompilationDir, NewCU->getUniqueID()); 737 738 NewCU->addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer()); 739 NewCU->addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2, 740 DIUnit.getLanguage()); 741 NewCU->addString(Die, dwarf::DW_AT_name, FN); 742 743 // 2.17.1 requires that we use DW_AT_low_pc for a single entry point 744 // into an entity. We're using 0 (or a NULL label) for this. For 745 // split dwarf it's in the skeleton CU so omit it here. 746 if (!useSplitDwarf()) 747 NewCU->addLabelAddress(Die, dwarf::DW_AT_low_pc, NULL); 748 749 // Define start line table label for each Compile Unit. 750 MCSymbol *LineTableStartSym = Asm->GetTempSymbol("line_table_start", 751 NewCU->getUniqueID()); 752 Asm->OutStreamer.getContext().setMCLineTableSymbol(LineTableStartSym, 753 NewCU->getUniqueID()); 754 755 // Use a single line table if we are using .loc and generating assembly. 756 bool UseTheFirstCU = 757 (Asm->TM.hasMCUseLoc() && Asm->OutStreamer.hasRawTextSupport()) || 758 (NewCU->getUniqueID() == 0); 759 760 if (!useSplitDwarf()) { 761 // DW_AT_stmt_list is a offset of line number information for this 762 // compile unit in debug_line section. For split dwarf this is 763 // left in the skeleton CU and so not included. 764 // The line table entries are not always emitted in assembly, so it 765 // is not okay to use line_table_start here. 766 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 767 NewCU->addLabel(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 768 UseTheFirstCU ? Asm->GetTempSymbol("section_line") 769 : LineTableStartSym); 770 else if (UseTheFirstCU) 771 NewCU->addUInt(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4, 0); 772 else 773 NewCU->addDelta(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4, 774 LineTableStartSym, DwarfLineSectionSym); 775 776 // If we're using split dwarf the compilation dir is going to be in the 777 // skeleton CU and so we don't need to duplicate it here. 778 if (!CompilationDir.empty()) 779 NewCU->addString(Die, dwarf::DW_AT_comp_dir, CompilationDir); 780 781 // Flags to let the linker know we have emitted new style pubnames. Only 782 // emit it here if we don't have a skeleton CU for split dwarf. 783 if (GenerateGnuPubSections) { 784 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 785 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubnames, 786 dwarf::DW_FORM_sec_offset, 787 Asm->GetTempSymbol("gnu_pubnames", 788 NewCU->getUniqueID())); 789 else 790 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_data4, 791 Asm->GetTempSymbol("gnu_pubnames", 792 NewCU->getUniqueID()), 793 DwarfGnuPubNamesSectionSym); 794 795 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 796 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubtypes, 797 dwarf::DW_FORM_sec_offset, 798 Asm->GetTempSymbol("gnu_pubtypes", 799 NewCU->getUniqueID())); 800 else 801 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_data4, 802 Asm->GetTempSymbol("gnu_pubtypes", 803 NewCU->getUniqueID()), 804 DwarfGnuPubTypesSectionSym); 805 } 806 } 807 808 if (DIUnit.isOptimized()) 809 NewCU->addFlag(Die, dwarf::DW_AT_APPLE_optimized); 810 811 StringRef Flags = DIUnit.getFlags(); 812 if (!Flags.empty()) 813 NewCU->addString(Die, dwarf::DW_AT_APPLE_flags, Flags); 814 815 if (unsigned RVer = DIUnit.getRunTimeVersion()) 816 NewCU->addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers, 817 dwarf::DW_FORM_data1, RVer); 818 819 if (!FirstCU) 820 FirstCU = NewCU; 821 822 InfoHolder.addUnit(NewCU); 823 824 CUMap.insert(std::make_pair(N, NewCU)); 825 return NewCU; 826} 827 828// Construct subprogram DIE. 829void DwarfDebug::constructSubprogramDIE(CompileUnit *TheCU, const MDNode *N) { 830 assert(!SPMap[N] && "Trying to create a subprogram DIE twice!"); 831 832 DISubprogram SP(N); 833 if (!SP.isDefinition()) 834 // This is a method declaration which will be handled while constructing 835 // class type. 836 return; 837 838 DIE *SubprogramDie = TheCU->getOrCreateSubprogramDIE(SP); 839 SPMap[N] = TheCU; 840 841 // Expose as a global name. 842 TheCU->addGlobalName(SP.getName(), SubprogramDie); 843} 844 845void DwarfDebug::constructImportedEntityDIE(CompileUnit *TheCU, 846 const MDNode *N) { 847 DIImportedEntity Module(N); 848 if (!Module.Verify()) 849 return; 850 if (DIE *D = TheCU->getOrCreateContextDIE(Module.getContext())) 851 constructImportedEntityDIE(TheCU, Module, D); 852} 853 854void DwarfDebug::constructImportedEntityDIE(CompileUnit *TheCU, const MDNode *N, 855 DIE *Context) { 856 DIImportedEntity Module(N); 857 if (!Module.Verify()) 858 return; 859 return constructImportedEntityDIE(TheCU, Module, Context); 860} 861 862void DwarfDebug::constructImportedEntityDIE(CompileUnit *TheCU, 863 const DIImportedEntity &Module, 864 DIE *Context) { 865 assert(Module.Verify() && 866 "Use one of the MDNode * overloads to handle invalid metadata"); 867 assert(Context && "Should always have a context for an imported_module"); 868 DIE *IMDie = new DIE(Module.getTag()); 869 TheCU->insertDIE(Module, IMDie); 870 DIE *EntityDie; 871 DIDescriptor Entity = Module.getEntity(); 872 if (Entity.isNameSpace()) 873 EntityDie = TheCU->getOrCreateNameSpace(DINameSpace(Entity)); 874 else if (Entity.isSubprogram()) 875 EntityDie = TheCU->getOrCreateSubprogramDIE(DISubprogram(Entity)); 876 else if (Entity.isType()) 877 EntityDie = TheCU->getOrCreateTypeDIE(DIType(Entity)); 878 else 879 EntityDie = TheCU->getDIE(Entity); 880 unsigned FileID = getOrCreateSourceID(Module.getContext().getFilename(), 881 Module.getContext().getDirectory(), 882 TheCU->getUniqueID()); 883 TheCU->addUInt(IMDie, dwarf::DW_AT_decl_file, 0, FileID); 884 TheCU->addUInt(IMDie, dwarf::DW_AT_decl_line, 0, Module.getLineNumber()); 885 TheCU->addDIEEntry(IMDie, dwarf::DW_AT_import, EntityDie); 886 StringRef Name = Module.getName(); 887 if (!Name.empty()) 888 TheCU->addString(IMDie, dwarf::DW_AT_name, Name); 889 Context->addChild(IMDie); 890} 891 892// Emit all Dwarf sections that should come prior to the content. Create 893// global DIEs and emit initial debug info sections. This is invoked by 894// the target AsmPrinter. 895void DwarfDebug::beginModule() { 896 if (DisableDebugInfoPrinting) 897 return; 898 899 const Module *M = MMI->getModule(); 900 901 // If module has named metadata anchors then use them, otherwise scan the 902 // module using debug info finder to collect debug info. 903 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu"); 904 if (!CU_Nodes) 905 return; 906 TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes); 907 908 // Emit initial sections so we can reference labels later. 909 emitSectionLabels(); 910 911 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) { 912 DICompileUnit CUNode(CU_Nodes->getOperand(i)); 913 CompileUnit *CU = constructCompileUnit(CUNode); 914 DIArray ImportedEntities = CUNode.getImportedEntities(); 915 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i) 916 ScopesWithImportedEntities.push_back(std::make_pair( 917 DIImportedEntity(ImportedEntities.getElement(i)).getContext(), 918 ImportedEntities.getElement(i))); 919 std::sort(ScopesWithImportedEntities.begin(), 920 ScopesWithImportedEntities.end(), less_first()); 921 DIArray GVs = CUNode.getGlobalVariables(); 922 for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i) 923 CU->createGlobalVariableDIE(GVs.getElement(i)); 924 DIArray SPs = CUNode.getSubprograms(); 925 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) 926 constructSubprogramDIE(CU, SPs.getElement(i)); 927 DIArray EnumTypes = CUNode.getEnumTypes(); 928 for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i) 929 CU->getOrCreateTypeDIE(EnumTypes.getElement(i)); 930 DIArray RetainedTypes = CUNode.getRetainedTypes(); 931 for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i) 932 CU->getOrCreateTypeDIE(RetainedTypes.getElement(i)); 933 // Emit imported_modules last so that the relevant context is already 934 // available. 935 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i) 936 constructImportedEntityDIE(CU, ImportedEntities.getElement(i)); 937 } 938 939 // Tell MMI that we have debug info. 940 MMI->setDebugInfoAvailability(true); 941 942 // Prime section data. 943 SectionMap[Asm->getObjFileLowering().getTextSection()]; 944} 945 946// Attach DW_AT_inline attribute with inlined subprogram DIEs. 947void DwarfDebug::computeInlinedDIEs() { 948 // Attach DW_AT_inline attribute with inlined subprogram DIEs. 949 for (SmallPtrSet<DIE *, 4>::iterator AI = InlinedSubprogramDIEs.begin(), 950 AE = InlinedSubprogramDIEs.end(); AI != AE; ++AI) { 951 DIE *ISP = *AI; 952 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, 0, dwarf::DW_INL_inlined); 953 } 954 for (DenseMap<const MDNode *, DIE *>::iterator AI = AbstractSPDies.begin(), 955 AE = AbstractSPDies.end(); AI != AE; ++AI) { 956 DIE *ISP = AI->second; 957 if (InlinedSubprogramDIEs.count(ISP)) 958 continue; 959 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, 0, dwarf::DW_INL_inlined); 960 } 961} 962 963// Collect info for variables that were optimized out. 964void DwarfDebug::collectDeadVariables() { 965 const Module *M = MMI->getModule(); 966 DenseMap<const MDNode *, LexicalScope *> DeadFnScopeMap; 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 LexicalScope *Scope = 985 new LexicalScope(NULL, DIDescriptor(SP), NULL, false); 986 DeadFnScopeMap[SP] = Scope; 987 988 // Construct subprogram DIE and add variables DIEs. 989 CompileUnit *SPCU = CUMap.lookup(TheCU); 990 assert(SPCU && "Unable to find Compile Unit!"); 991 DIE *SPDIE = SPCU->getDIE(SP); 992 assert(SPDIE && "Subprogram wasn't created?"); 993 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) { 994 DIVariable DV(Variables.getElement(vi)); 995 if (!DV.isVariable()) 996 continue; 997 DbgVariable NewVar(DV, NULL, this); 998 if (DIE *VariableDIE = 999 SPCU->constructVariableDIE(&NewVar, Scope->isAbstractScope())) 1000 SPDIE->addChild(VariableDIE); 1001 } 1002 } 1003 } 1004 } 1005 DeleteContainerSeconds(DeadFnScopeMap); 1006} 1007 1008// Type Signature [7.27] and ODR Hash code. 1009 1010/// \brief Grabs the string in whichever attribute is passed in and returns 1011/// a reference to it. Returns "" if the attribute doesn't exist. 1012static StringRef getDIEStringAttr(DIE *Die, unsigned Attr) { 1013 DIEValue *V = Die->findAttribute(Attr); 1014 1015 if (DIEString *S = dyn_cast_or_null<DIEString>(V)) 1016 return S->getString(); 1017 1018 return StringRef(""); 1019} 1020 1021/// Return true if the current DIE is contained within an anonymous namespace. 1022static bool isContainedInAnonNamespace(DIE *Die) { 1023 DIE *Parent = Die->getParent(); 1024 1025 while (Parent) { 1026 if (Parent->getTag() == dwarf::DW_TAG_namespace && 1027 getDIEStringAttr(Parent, dwarf::DW_AT_name) == "") 1028 return true; 1029 Parent = Parent->getParent(); 1030 } 1031 1032 return false; 1033} 1034 1035/// Test if the current CU language is C++ and that we have 1036/// a named type that is not contained in an anonymous namespace. 1037static bool shouldAddODRHash(CompileUnit *CU, DIE *Die) { 1038 return CU->getLanguage() == dwarf::DW_LANG_C_plus_plus && 1039 getDIEStringAttr(Die, dwarf::DW_AT_name) != "" && 1040 !isContainedInAnonNamespace(Die); 1041} 1042 1043void DwarfDebug::finalizeModuleInfo() { 1044 // Collect info for variables that were optimized out. 1045 collectDeadVariables(); 1046 1047 // Attach DW_AT_inline attribute with inlined subprogram DIEs. 1048 computeInlinedDIEs(); 1049 1050 // Split out type units and conditionally add an ODR tag to the split 1051 // out type. 1052 // FIXME: Do type splitting. 1053 for (unsigned i = 0, e = TypeUnits.size(); i != e; ++i) { 1054 DIE *Die = TypeUnits[i]; 1055 DIEHash Hash; 1056 // If we've requested ODR hashes and it's applicable for an ODR hash then 1057 // add the ODR signature now. 1058 // FIXME: This should be added onto the type unit, not the type, but this 1059 // works as an intermediate stage. 1060 if (GenerateODRHash && shouldAddODRHash(CUMap.begin()->second, Die)) 1061 CUMap.begin()->second->addUInt(Die, dwarf::DW_AT_GNU_odr_signature, 1062 dwarf::DW_FORM_data8, 1063 Hash.computeDIEODRSignature(Die)); 1064 } 1065 1066 // Handle anything that needs to be done on a per-cu basis. 1067 for (DenseMap<const MDNode *, CompileUnit *>::iterator CUI = CUMap.begin(), 1068 CUE = CUMap.end(); 1069 CUI != CUE; ++CUI) { 1070 CompileUnit *TheCU = CUI->second; 1071 // Emit DW_AT_containing_type attribute to connect types with their 1072 // vtable holding type. 1073 TheCU->constructContainingTypeDIEs(); 1074 1075 // If we're splitting the dwarf out now that we've got the entire 1076 // CU then construct a skeleton CU based upon it. 1077 if (useSplitDwarf()) { 1078 uint64_t ID = 0; 1079 if (GenerateCUHash) { 1080 DIEHash CUHash; 1081 ID = CUHash.computeCUSignature(TheCU->getCUDie()); 1082 } 1083 // This should be a unique identifier when we want to build .dwp files. 1084 TheCU->addUInt(TheCU->getCUDie(), dwarf::DW_AT_GNU_dwo_id, 1085 dwarf::DW_FORM_data8, ID); 1086 // Now construct the skeleton CU associated. 1087 CompileUnit *SkCU = constructSkeletonCU(TheCU); 1088 // This should be a unique identifier when we want to build .dwp files. 1089 SkCU->addUInt(SkCU->getCUDie(), dwarf::DW_AT_GNU_dwo_id, 1090 dwarf::DW_FORM_data8, ID); 1091 } 1092 } 1093 1094 // Compute DIE offsets and sizes. 1095 InfoHolder.computeSizeAndOffsets(); 1096 if (useSplitDwarf()) 1097 SkeletonHolder.computeSizeAndOffsets(); 1098} 1099 1100void DwarfDebug::endSections() { 1101 // Filter labels by section. 1102 for (size_t n = 0; n < ArangeLabels.size(); n++) { 1103 const SymbolCU &SCU = ArangeLabels[n]; 1104 if (SCU.Sym->isInSection()) { 1105 // Make a note of this symbol and it's section. 1106 const MCSection *Section = &SCU.Sym->getSection(); 1107 if (!Section->getKind().isMetadata()) 1108 SectionMap[Section].push_back(SCU); 1109 } else { 1110 // Some symbols (e.g. common/bss on mach-o) can have no section but still 1111 // appear in the output. This sucks as we rely on sections to build 1112 // arange spans. We can do it without, but it's icky. 1113 SectionMap[NULL].push_back(SCU); 1114 } 1115 } 1116 1117 // Build a list of sections used. 1118 std::vector<const MCSection *> Sections; 1119 for (SectionMapType::iterator it = SectionMap.begin(); it != SectionMap.end(); 1120 it++) { 1121 const MCSection *Section = it->first; 1122 Sections.push_back(Section); 1123 } 1124 1125 // Sort the sections into order. 1126 // This is only done to ensure consistent output order across different runs. 1127 std::sort(Sections.begin(), Sections.end(), SectionSort); 1128 1129 // Add terminating symbols for each section. 1130 for (unsigned ID=0;ID<Sections.size();ID++) { 1131 const MCSection *Section = Sections[ID]; 1132 MCSymbol *Sym = NULL; 1133 1134 if (Section) { 1135 // We can't call MCSection::getLabelEndName, as it's only safe to do so 1136 // if we know the section name up-front. For user-created sections, the resulting 1137 // label may not be valid to use as a label. (section names can use a greater 1138 // set of characters on some systems) 1139 Sym = Asm->GetTempSymbol("debug_end", ID); 1140 Asm->OutStreamer.SwitchSection(Section); 1141 Asm->OutStreamer.EmitLabel(Sym); 1142 } 1143 1144 // Insert a final terminator. 1145 SectionMap[Section].push_back(SymbolCU(NULL, Sym)); 1146 } 1147} 1148 1149// Emit all Dwarf sections that should come after the content. 1150void DwarfDebug::endModule() { 1151 1152 if (!FirstCU) return; 1153 1154 // End any existing sections. 1155 // TODO: Does this need to happen? 1156 endSections(); 1157 1158 // Finalize the debug info for the module. 1159 finalizeModuleInfo(); 1160 1161 if (!useSplitDwarf()) { 1162 emitDebugStr(); 1163 1164 // Emit all the DIEs into a debug info section. 1165 emitDebugInfo(); 1166 1167 // Corresponding abbreviations into a abbrev section. 1168 emitAbbreviations(); 1169 1170 // Emit info into a debug loc section. 1171 emitDebugLoc(); 1172 1173 // Emit info into a debug aranges section. 1174 emitDebugARanges(); 1175 1176 // Emit info into a debug ranges section. 1177 emitDebugRanges(); 1178 1179 // Emit info into a debug macinfo section. 1180 emitDebugMacInfo(); 1181 1182 } else { 1183 // TODO: Fill this in for separated debug sections and separate 1184 // out information into new sections. 1185 emitDebugStr(); 1186 if (useSplitDwarf()) 1187 emitDebugStrDWO(); 1188 1189 // Emit the debug info section and compile units. 1190 emitDebugInfo(); 1191 emitDebugInfoDWO(); 1192 1193 // Corresponding abbreviations into a abbrev section. 1194 emitAbbreviations(); 1195 emitDebugAbbrevDWO(); 1196 1197 // Emit info into a debug loc section. 1198 emitDebugLoc(); 1199 1200 // Emit info into a debug aranges section. 1201 emitDebugARanges(); 1202 1203 // Emit info into a debug ranges section. 1204 emitDebugRanges(); 1205 1206 // Emit info into a debug macinfo section. 1207 emitDebugMacInfo(); 1208 1209 // Emit DWO addresses. 1210 InfoHolder.emitAddresses(Asm->getObjFileLowering().getDwarfAddrSection()); 1211 1212 } 1213 1214 // Emit info into the dwarf accelerator table sections. 1215 if (useDwarfAccelTables()) { 1216 emitAccelNames(); 1217 emitAccelObjC(); 1218 emitAccelNamespaces(); 1219 emitAccelTypes(); 1220 } 1221 1222 // Emit the pubnames and pubtypes sections if requested. 1223 if (HasDwarfPubSections) { 1224 emitDebugPubNames(GenerateGnuPubSections); 1225 emitDebugPubTypes(GenerateGnuPubSections); 1226 } 1227 1228 // clean up. 1229 SPMap.clear(); 1230 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 1231 E = CUMap.end(); I != E; ++I) 1232 delete I->second; 1233 1234 for (SmallVectorImpl<CompileUnit *>::iterator I = SkeletonCUs.begin(), 1235 E = SkeletonCUs.end(); I != E; ++I) 1236 delete *I; 1237 1238 // Reset these for the next Module if we have one. 1239 FirstCU = NULL; 1240} 1241 1242// Find abstract variable, if any, associated with Var. 1243DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &DV, 1244 DebugLoc ScopeLoc) { 1245 LLVMContext &Ctx = DV->getContext(); 1246 // More then one inlined variable corresponds to one abstract variable. 1247 DIVariable Var = cleanseInlinedVariable(DV, Ctx); 1248 DbgVariable *AbsDbgVariable = AbstractVariables.lookup(Var); 1249 if (AbsDbgVariable) 1250 return AbsDbgVariable; 1251 1252 LexicalScope *Scope = LScopes.findAbstractScope(ScopeLoc.getScope(Ctx)); 1253 if (!Scope) 1254 return NULL; 1255 1256 AbsDbgVariable = new DbgVariable(Var, NULL, this); 1257 addScopeVariable(Scope, AbsDbgVariable); 1258 AbstractVariables[Var] = AbsDbgVariable; 1259 return AbsDbgVariable; 1260} 1261 1262// If Var is a current function argument then add it to CurrentFnArguments list. 1263bool DwarfDebug::addCurrentFnArgument(const MachineFunction *MF, 1264 DbgVariable *Var, LexicalScope *Scope) { 1265 if (!LScopes.isCurrentFunctionScope(Scope)) 1266 return false; 1267 DIVariable DV = Var->getVariable(); 1268 if (DV.getTag() != dwarf::DW_TAG_arg_variable) 1269 return false; 1270 unsigned ArgNo = DV.getArgNumber(); 1271 if (ArgNo == 0) 1272 return false; 1273 1274 size_t Size = CurrentFnArguments.size(); 1275 if (Size == 0) 1276 CurrentFnArguments.resize(MF->getFunction()->arg_size()); 1277 // llvm::Function argument size is not good indicator of how many 1278 // arguments does the function have at source level. 1279 if (ArgNo > Size) 1280 CurrentFnArguments.resize(ArgNo * 2); 1281 CurrentFnArguments[ArgNo - 1] = Var; 1282 return true; 1283} 1284 1285// Collect variable information from side table maintained by MMI. 1286void 1287DwarfDebug::collectVariableInfoFromMMITable(const MachineFunction *MF, 1288 SmallPtrSet<const MDNode *, 16> &Processed) { 1289 MachineModuleInfo::VariableDbgInfoMapTy &VMap = MMI->getVariableDbgInfo(); 1290 for (MachineModuleInfo::VariableDbgInfoMapTy::iterator VI = VMap.begin(), 1291 VE = VMap.end(); VI != VE; ++VI) { 1292 const MDNode *Var = VI->first; 1293 if (!Var) continue; 1294 Processed.insert(Var); 1295 DIVariable DV(Var); 1296 const std::pair<unsigned, DebugLoc> &VP = VI->second; 1297 1298 LexicalScope *Scope = LScopes.findLexicalScope(VP.second); 1299 1300 // If variable scope is not found then skip this variable. 1301 if (Scope == 0) 1302 continue; 1303 1304 DbgVariable *AbsDbgVariable = findAbstractVariable(DV, VP.second); 1305 DbgVariable *RegVar = new DbgVariable(DV, AbsDbgVariable, this); 1306 RegVar->setFrameIndex(VP.first); 1307 if (!addCurrentFnArgument(MF, RegVar, Scope)) 1308 addScopeVariable(Scope, RegVar); 1309 if (AbsDbgVariable) 1310 AbsDbgVariable->setFrameIndex(VP.first); 1311 } 1312} 1313 1314// Return true if debug value, encoded by DBG_VALUE instruction, is in a 1315// defined reg. 1316static bool isDbgValueInDefinedReg(const MachineInstr *MI) { 1317 assert(MI->isDebugValue() && "Invalid DBG_VALUE machine instruction!"); 1318 return MI->getNumOperands() == 3 && 1319 MI->getOperand(0).isReg() && MI->getOperand(0).getReg() && 1320 (MI->getOperand(1).isImm() || 1321 (MI->getOperand(1).isReg() && MI->getOperand(1).getReg() == 0U)); 1322} 1323 1324// Get .debug_loc entry for the instruction range starting at MI. 1325static DotDebugLocEntry getDebugLocEntry(AsmPrinter *Asm, 1326 const MCSymbol *FLabel, 1327 const MCSymbol *SLabel, 1328 const MachineInstr *MI) { 1329 const MDNode *Var = MI->getOperand(MI->getNumOperands() - 1).getMetadata(); 1330 1331 assert(MI->getNumOperands() == 3); 1332 if (MI->getOperand(0).isReg()) { 1333 MachineLocation MLoc; 1334 // If the second operand is an immediate, this is a 1335 // register-indirect address. 1336 if (!MI->getOperand(1).isImm()) 1337 MLoc.set(MI->getOperand(0).getReg()); 1338 else 1339 MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm()); 1340 return DotDebugLocEntry(FLabel, SLabel, MLoc, Var); 1341 } 1342 if (MI->getOperand(0).isImm()) 1343 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getImm()); 1344 if (MI->getOperand(0).isFPImm()) 1345 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getFPImm()); 1346 if (MI->getOperand(0).isCImm()) 1347 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getCImm()); 1348 1349 llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!"); 1350} 1351 1352// Find variables for each lexical scope. 1353void 1354DwarfDebug::collectVariableInfo(const MachineFunction *MF, 1355 SmallPtrSet<const MDNode *, 16> &Processed) { 1356 1357 // Grab the variable info that was squirreled away in the MMI side-table. 1358 collectVariableInfoFromMMITable(MF, Processed); 1359 1360 for (SmallVectorImpl<const MDNode*>::const_iterator 1361 UVI = UserVariables.begin(), UVE = UserVariables.end(); UVI != UVE; 1362 ++UVI) { 1363 const MDNode *Var = *UVI; 1364 if (Processed.count(Var)) 1365 continue; 1366 1367 // History contains relevant DBG_VALUE instructions for Var and instructions 1368 // clobbering it. 1369 SmallVectorImpl<const MachineInstr*> &History = DbgValues[Var]; 1370 if (History.empty()) 1371 continue; 1372 const MachineInstr *MInsn = History.front(); 1373 1374 DIVariable DV(Var); 1375 LexicalScope *Scope = NULL; 1376 if (DV.getTag() == dwarf::DW_TAG_arg_variable && 1377 DISubprogram(DV.getContext()).describes(MF->getFunction())) 1378 Scope = LScopes.getCurrentFunctionScope(); 1379 else if (MDNode *IA = DV.getInlinedAt()) 1380 Scope = LScopes.findInlinedScope(DebugLoc::getFromDILocation(IA)); 1381 else 1382 Scope = LScopes.findLexicalScope(cast<MDNode>(DV->getOperand(1))); 1383 // If variable scope is not found then skip this variable. 1384 if (!Scope) 1385 continue; 1386 1387 Processed.insert(DV); 1388 assert(MInsn->isDebugValue() && "History must begin with debug value"); 1389 DbgVariable *AbsVar = findAbstractVariable(DV, MInsn->getDebugLoc()); 1390 DbgVariable *RegVar = new DbgVariable(DV, AbsVar, this); 1391 if (!addCurrentFnArgument(MF, RegVar, Scope)) 1392 addScopeVariable(Scope, RegVar); 1393 if (AbsVar) 1394 AbsVar->setMInsn(MInsn); 1395 1396 // Simplify ranges that are fully coalesced. 1397 if (History.size() <= 1 || (History.size() == 2 && 1398 MInsn->isIdenticalTo(History.back()))) { 1399 RegVar->setMInsn(MInsn); 1400 continue; 1401 } 1402 1403 // Handle multiple DBG_VALUE instructions describing one variable. 1404 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size()); 1405 1406 for (SmallVectorImpl<const MachineInstr*>::const_iterator 1407 HI = History.begin(), HE = History.end(); HI != HE; ++HI) { 1408 const MachineInstr *Begin = *HI; 1409 assert(Begin->isDebugValue() && "Invalid History entry"); 1410 1411 // Check if DBG_VALUE is truncating a range. 1412 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() 1413 && !Begin->getOperand(0).getReg()) 1414 continue; 1415 1416 // Compute the range for a register location. 1417 const MCSymbol *FLabel = getLabelBeforeInsn(Begin); 1418 const MCSymbol *SLabel = 0; 1419 1420 if (HI + 1 == HE) 1421 // If Begin is the last instruction in History then its value is valid 1422 // until the end of the function. 1423 SLabel = FunctionEndSym; 1424 else { 1425 const MachineInstr *End = HI[1]; 1426 DEBUG(dbgs() << "DotDebugLoc Pair:\n" 1427 << "\t" << *Begin << "\t" << *End << "\n"); 1428 if (End->isDebugValue()) 1429 SLabel = getLabelBeforeInsn(End); 1430 else { 1431 // End is a normal instruction clobbering the range. 1432 SLabel = getLabelAfterInsn(End); 1433 assert(SLabel && "Forgot label after clobber instruction"); 1434 ++HI; 1435 } 1436 } 1437 1438 // The value is valid until the next DBG_VALUE or clobber. 1439 DotDebugLocEntries.push_back(getDebugLocEntry(Asm, FLabel, SLabel, 1440 Begin)); 1441 } 1442 DotDebugLocEntries.push_back(DotDebugLocEntry()); 1443 } 1444 1445 // Collect info for variables that were optimized out. 1446 LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); 1447 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables(); 1448 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) { 1449 DIVariable DV(Variables.getElement(i)); 1450 if (!DV || !DV.isVariable() || !Processed.insert(DV)) 1451 continue; 1452 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext())) 1453 addScopeVariable(Scope, new DbgVariable(DV, NULL, this)); 1454 } 1455} 1456 1457// Return Label preceding the instruction. 1458MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) { 1459 MCSymbol *Label = LabelsBeforeInsn.lookup(MI); 1460 assert(Label && "Didn't insert label before instruction"); 1461 return Label; 1462} 1463 1464// Return Label immediately following the instruction. 1465MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) { 1466 return LabelsAfterInsn.lookup(MI); 1467} 1468 1469// Process beginning of an instruction. 1470void DwarfDebug::beginInstruction(const MachineInstr *MI) { 1471 // Check if source location changes, but ignore DBG_VALUE locations. 1472 if (!MI->isDebugValue()) { 1473 DebugLoc DL = MI->getDebugLoc(); 1474 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) { 1475 unsigned Flags = 0; 1476 PrevInstLoc = DL; 1477 if (DL == PrologEndLoc) { 1478 Flags |= DWARF2_FLAG_PROLOGUE_END; 1479 PrologEndLoc = DebugLoc(); 1480 } 1481 if (PrologEndLoc.isUnknown()) 1482 Flags |= DWARF2_FLAG_IS_STMT; 1483 1484 if (!DL.isUnknown()) { 1485 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext()); 1486 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags); 1487 } else 1488 recordSourceLine(0, 0, 0, 0); 1489 } 1490 } 1491 1492 // Insert labels where requested. 1493 DenseMap<const MachineInstr*, MCSymbol*>::iterator I = 1494 LabelsBeforeInsn.find(MI); 1495 1496 // No label needed. 1497 if (I == LabelsBeforeInsn.end()) 1498 return; 1499 1500 // Label already assigned. 1501 if (I->second) 1502 return; 1503 1504 if (!PrevLabel) { 1505 PrevLabel = MMI->getContext().CreateTempSymbol(); 1506 Asm->OutStreamer.EmitLabel(PrevLabel); 1507 } 1508 I->second = PrevLabel; 1509} 1510 1511// Process end of an instruction. 1512void DwarfDebug::endInstruction(const MachineInstr *MI) { 1513 // Don't create a new label after DBG_VALUE instructions. 1514 // They don't generate code. 1515 if (!MI->isDebugValue()) 1516 PrevLabel = 0; 1517 1518 DenseMap<const MachineInstr*, MCSymbol*>::iterator I = 1519 LabelsAfterInsn.find(MI); 1520 1521 // No label needed. 1522 if (I == LabelsAfterInsn.end()) 1523 return; 1524 1525 // Label already assigned. 1526 if (I->second) 1527 return; 1528 1529 // We need a label after this instruction. 1530 if (!PrevLabel) { 1531 PrevLabel = MMI->getContext().CreateTempSymbol(); 1532 Asm->OutStreamer.EmitLabel(PrevLabel); 1533 } 1534 I->second = PrevLabel; 1535} 1536 1537// Each LexicalScope has first instruction and last instruction to mark 1538// beginning and end of a scope respectively. Create an inverse map that list 1539// scopes starts (and ends) with an instruction. One instruction may start (or 1540// end) multiple scopes. Ignore scopes that are not reachable. 1541void DwarfDebug::identifyScopeMarkers() { 1542 SmallVector<LexicalScope *, 4> WorkList; 1543 WorkList.push_back(LScopes.getCurrentFunctionScope()); 1544 while (!WorkList.empty()) { 1545 LexicalScope *S = WorkList.pop_back_val(); 1546 1547 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren(); 1548 if (!Children.empty()) 1549 for (SmallVectorImpl<LexicalScope *>::const_iterator SI = Children.begin(), 1550 SE = Children.end(); SI != SE; ++SI) 1551 WorkList.push_back(*SI); 1552 1553 if (S->isAbstractScope()) 1554 continue; 1555 1556 const SmallVectorImpl<InsnRange> &Ranges = S->getRanges(); 1557 if (Ranges.empty()) 1558 continue; 1559 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 1560 RE = Ranges.end(); RI != RE; ++RI) { 1561 assert(RI->first && "InsnRange does not have first instruction!"); 1562 assert(RI->second && "InsnRange does not have second instruction!"); 1563 requestLabelBeforeInsn(RI->first); 1564 requestLabelAfterInsn(RI->second); 1565 } 1566 } 1567} 1568 1569// Get MDNode for DebugLoc's scope. 1570static MDNode *getScopeNode(DebugLoc DL, const LLVMContext &Ctx) { 1571 if (MDNode *InlinedAt = DL.getInlinedAt(Ctx)) 1572 return getScopeNode(DebugLoc::getFromDILocation(InlinedAt), Ctx); 1573 return DL.getScope(Ctx); 1574} 1575 1576// Walk up the scope chain of given debug loc and find line number info 1577// for the function. 1578static DebugLoc getFnDebugLoc(DebugLoc DL, const LLVMContext &Ctx) { 1579 const MDNode *Scope = getScopeNode(DL, Ctx); 1580 DISubprogram SP = getDISubprogram(Scope); 1581 if (SP.isSubprogram()) { 1582 // Check for number of operands since the compatibility is 1583 // cheap here. 1584 if (SP->getNumOperands() > 19) 1585 return DebugLoc::get(SP.getScopeLineNumber(), 0, SP); 1586 else 1587 return DebugLoc::get(SP.getLineNumber(), 0, SP); 1588 } 1589 1590 return DebugLoc(); 1591} 1592 1593// Gather pre-function debug information. Assumes being called immediately 1594// after the function entry point has been emitted. 1595void DwarfDebug::beginFunction(const MachineFunction *MF) { 1596 if (!MMI->hasDebugInfo()) return; 1597 LScopes.initialize(*MF); 1598 if (LScopes.empty()) return; 1599 identifyScopeMarkers(); 1600 1601 // Set DwarfCompileUnitID in MCContext to the Compile Unit this function 1602 // belongs to. 1603 LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); 1604 CompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode()); 1605 assert(TheCU && "Unable to find compile unit!"); 1606 if (Asm->TM.hasMCUseLoc() && Asm->OutStreamer.hasRawTextSupport()) 1607 // Use a single line table if we are using .loc and generating assembly. 1608 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0); 1609 else 1610 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID()); 1611 1612 FunctionBeginSym = Asm->GetTempSymbol("func_begin", 1613 Asm->getFunctionNumber()); 1614 // Assumes in correct section after the entry point. 1615 Asm->OutStreamer.EmitLabel(FunctionBeginSym); 1616 1617 assert(UserVariables.empty() && DbgValues.empty() && "Maps weren't cleaned"); 1618 1619 const TargetRegisterInfo *TRI = Asm->TM.getRegisterInfo(); 1620 // LiveUserVar - Map physreg numbers to the MDNode they contain. 1621 std::vector<const MDNode*> LiveUserVar(TRI->getNumRegs()); 1622 1623 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end(); 1624 I != E; ++I) { 1625 bool AtBlockEntry = true; 1626 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end(); 1627 II != IE; ++II) { 1628 const MachineInstr *MI = II; 1629 1630 if (MI->isDebugValue()) { 1631 assert(MI->getNumOperands() > 1 && "Invalid machine instruction!"); 1632 1633 // Keep track of user variables. 1634 const MDNode *Var = 1635 MI->getOperand(MI->getNumOperands() - 1).getMetadata(); 1636 1637 // Variable is in a register, we need to check for clobbers. 1638 if (isDbgValueInDefinedReg(MI)) 1639 LiveUserVar[MI->getOperand(0).getReg()] = Var; 1640 1641 // Check the history of this variable. 1642 SmallVectorImpl<const MachineInstr*> &History = DbgValues[Var]; 1643 if (History.empty()) { 1644 UserVariables.push_back(Var); 1645 // The first mention of a function argument gets the FunctionBeginSym 1646 // label, so arguments are visible when breaking at function entry. 1647 DIVariable DV(Var); 1648 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable && 1649 DISubprogram(getDISubprogram(DV.getContext())) 1650 .describes(MF->getFunction())) 1651 LabelsBeforeInsn[MI] = FunctionBeginSym; 1652 } else { 1653 // We have seen this variable before. Try to coalesce DBG_VALUEs. 1654 const MachineInstr *Prev = History.back(); 1655 if (Prev->isDebugValue()) { 1656 // Coalesce identical entries at the end of History. 1657 if (History.size() >= 2 && 1658 Prev->isIdenticalTo(History[History.size() - 2])) { 1659 DEBUG(dbgs() << "Coalescing identical DBG_VALUE entries:\n" 1660 << "\t" << *Prev 1661 << "\t" << *History[History.size() - 2] << "\n"); 1662 History.pop_back(); 1663 } 1664 1665 // Terminate old register assignments that don't reach MI; 1666 MachineFunction::const_iterator PrevMBB = Prev->getParent(); 1667 if (PrevMBB != I && (!AtBlockEntry || llvm::next(PrevMBB) != I) && 1668 isDbgValueInDefinedReg(Prev)) { 1669 // Previous register assignment needs to terminate at the end of 1670 // its basic block. 1671 MachineBasicBlock::const_iterator LastMI = 1672 PrevMBB->getLastNonDebugInstr(); 1673 if (LastMI == PrevMBB->end()) { 1674 // Drop DBG_VALUE for empty range. 1675 DEBUG(dbgs() << "Dropping DBG_VALUE for empty range:\n" 1676 << "\t" << *Prev << "\n"); 1677 History.pop_back(); 1678 } else if (llvm::next(PrevMBB) != PrevMBB->getParent()->end()) 1679 // Terminate after LastMI. 1680 History.push_back(LastMI); 1681 } 1682 } 1683 } 1684 History.push_back(MI); 1685 } else { 1686 // Not a DBG_VALUE instruction. 1687 if (!MI->isLabel()) 1688 AtBlockEntry = false; 1689 1690 // First known non-DBG_VALUE and non-frame setup location marks 1691 // the beginning of the function body. 1692 if (!MI->getFlag(MachineInstr::FrameSetup) && 1693 (PrologEndLoc.isUnknown() && !MI->getDebugLoc().isUnknown())) 1694 PrologEndLoc = MI->getDebugLoc(); 1695 1696 // Check if the instruction clobbers any registers with debug vars. 1697 for (MachineInstr::const_mop_iterator MOI = MI->operands_begin(), 1698 MOE = MI->operands_end(); MOI != MOE; ++MOI) { 1699 if (!MOI->isReg() || !MOI->isDef() || !MOI->getReg()) 1700 continue; 1701 for (MCRegAliasIterator AI(MOI->getReg(), TRI, true); 1702 AI.isValid(); ++AI) { 1703 unsigned Reg = *AI; 1704 const MDNode *Var = LiveUserVar[Reg]; 1705 if (!Var) 1706 continue; 1707 // Reg is now clobbered. 1708 LiveUserVar[Reg] = 0; 1709 1710 // Was MD last defined by a DBG_VALUE referring to Reg? 1711 DbgValueHistoryMap::iterator HistI = DbgValues.find(Var); 1712 if (HistI == DbgValues.end()) 1713 continue; 1714 SmallVectorImpl<const MachineInstr*> &History = HistI->second; 1715 if (History.empty()) 1716 continue; 1717 const MachineInstr *Prev = History.back(); 1718 // Sanity-check: Register assignments are terminated at the end of 1719 // their block. 1720 if (!Prev->isDebugValue() || Prev->getParent() != MI->getParent()) 1721 continue; 1722 // Is the variable still in Reg? 1723 if (!isDbgValueInDefinedReg(Prev) || 1724 Prev->getOperand(0).getReg() != Reg) 1725 continue; 1726 // Var is clobbered. Make sure the next instruction gets a label. 1727 History.push_back(MI); 1728 } 1729 } 1730 } 1731 } 1732 } 1733 1734 for (DbgValueHistoryMap::iterator I = DbgValues.begin(), E = DbgValues.end(); 1735 I != E; ++I) { 1736 SmallVectorImpl<const MachineInstr*> &History = I->second; 1737 if (History.empty()) 1738 continue; 1739 1740 // Make sure the final register assignments are terminated. 1741 const MachineInstr *Prev = History.back(); 1742 if (Prev->isDebugValue() && isDbgValueInDefinedReg(Prev)) { 1743 const MachineBasicBlock *PrevMBB = Prev->getParent(); 1744 MachineBasicBlock::const_iterator LastMI = 1745 PrevMBB->getLastNonDebugInstr(); 1746 if (LastMI == PrevMBB->end()) 1747 // Drop DBG_VALUE for empty range. 1748 History.pop_back(); 1749 else if (PrevMBB != &PrevMBB->getParent()->back()) { 1750 // Terminate after LastMI. 1751 History.push_back(LastMI); 1752 } 1753 } 1754 // Request labels for the full history. 1755 for (unsigned i = 0, e = History.size(); i != e; ++i) { 1756 const MachineInstr *MI = History[i]; 1757 if (MI->isDebugValue()) 1758 requestLabelBeforeInsn(MI); 1759 else 1760 requestLabelAfterInsn(MI); 1761 } 1762 } 1763 1764 PrevInstLoc = DebugLoc(); 1765 PrevLabel = FunctionBeginSym; 1766 1767 // Record beginning of function. 1768 if (!PrologEndLoc.isUnknown()) { 1769 DebugLoc FnStartDL = getFnDebugLoc(PrologEndLoc, 1770 MF->getFunction()->getContext()); 1771 recordSourceLine(FnStartDL.getLine(), FnStartDL.getCol(), 1772 FnStartDL.getScope(MF->getFunction()->getContext()), 1773 // We'd like to list the prologue as "not statements" but GDB behaves 1774 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing. 1775 DWARF2_FLAG_IS_STMT); 1776 } 1777} 1778 1779void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) { 1780 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS]; 1781 DIVariable DV = Var->getVariable(); 1782 // Variables with positive arg numbers are parameters. 1783 if (unsigned ArgNum = DV.getArgNumber()) { 1784 // Keep all parameters in order at the start of the variable list to ensure 1785 // function types are correct (no out-of-order parameters) 1786 // 1787 // This could be improved by only doing it for optimized builds (unoptimized 1788 // builds have the right order to begin with), searching from the back (this 1789 // would catch the unoptimized case quickly), or doing a binary search 1790 // rather than linear search. 1791 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin(); 1792 while (I != Vars.end()) { 1793 unsigned CurNum = (*I)->getVariable().getArgNumber(); 1794 // A local (non-parameter) variable has been found, insert immediately 1795 // before it. 1796 if (CurNum == 0) 1797 break; 1798 // A later indexed parameter has been found, insert immediately before it. 1799 if (CurNum > ArgNum) 1800 break; 1801 ++I; 1802 } 1803 Vars.insert(I, Var); 1804 return; 1805 } 1806 1807 Vars.push_back(Var); 1808} 1809 1810// Gather and emit post-function debug information. 1811void DwarfDebug::endFunction(const MachineFunction *MF) { 1812 if (!MMI->hasDebugInfo() || LScopes.empty()) return; 1813 1814 // Define end label for subprogram. 1815 FunctionEndSym = Asm->GetTempSymbol("func_end", 1816 Asm->getFunctionNumber()); 1817 // Assumes in correct section after the entry point. 1818 Asm->OutStreamer.EmitLabel(FunctionEndSym); 1819 // Set DwarfCompileUnitID in MCContext to default value. 1820 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0); 1821 1822 SmallPtrSet<const MDNode *, 16> ProcessedVars; 1823 collectVariableInfo(MF, ProcessedVars); 1824 1825 LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); 1826 CompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode()); 1827 assert(TheCU && "Unable to find compile unit!"); 1828 1829 // Construct abstract scopes. 1830 ArrayRef<LexicalScope *> AList = LScopes.getAbstractScopesList(); 1831 for (unsigned i = 0, e = AList.size(); i != e; ++i) { 1832 LexicalScope *AScope = AList[i]; 1833 DISubprogram SP(AScope->getScopeNode()); 1834 if (SP.isSubprogram()) { 1835 // Collect info for variables that were optimized out. 1836 DIArray Variables = SP.getVariables(); 1837 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) { 1838 DIVariable DV(Variables.getElement(i)); 1839 if (!DV || !DV.isVariable() || !ProcessedVars.insert(DV)) 1840 continue; 1841 // Check that DbgVariable for DV wasn't created earlier, when 1842 // findAbstractVariable() was called for inlined instance of DV. 1843 LLVMContext &Ctx = DV->getContext(); 1844 DIVariable CleanDV = cleanseInlinedVariable(DV, Ctx); 1845 if (AbstractVariables.lookup(CleanDV)) 1846 continue; 1847 if (LexicalScope *Scope = LScopes.findAbstractScope(DV.getContext())) 1848 addScopeVariable(Scope, new DbgVariable(DV, NULL, this)); 1849 } 1850 } 1851 if (ProcessedSPNodes.count(AScope->getScopeNode()) == 0) 1852 constructScopeDIE(TheCU, AScope); 1853 } 1854 1855 DIE *CurFnDIE = constructScopeDIE(TheCU, FnScope); 1856 1857 if (!MF->getTarget().Options.DisableFramePointerElim(*MF)) 1858 TheCU->addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr); 1859 1860 // Clear debug info 1861 for (ScopeVariablesMap::iterator 1862 I = ScopeVariables.begin(), E = ScopeVariables.end(); I != E; ++I) 1863 DeleteContainerPointers(I->second); 1864 ScopeVariables.clear(); 1865 DeleteContainerPointers(CurrentFnArguments); 1866 UserVariables.clear(); 1867 DbgValues.clear(); 1868 AbstractVariables.clear(); 1869 LabelsBeforeInsn.clear(); 1870 LabelsAfterInsn.clear(); 1871 PrevLabel = NULL; 1872} 1873 1874// Register a source line with debug info. Returns the unique label that was 1875// emitted and which provides correspondence to the source line list. 1876void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S, 1877 unsigned Flags) { 1878 StringRef Fn; 1879 StringRef Dir; 1880 unsigned Src = 1; 1881 if (S) { 1882 DIDescriptor Scope(S); 1883 1884 if (Scope.isCompileUnit()) { 1885 DICompileUnit CU(S); 1886 Fn = CU.getFilename(); 1887 Dir = CU.getDirectory(); 1888 } else if (Scope.isFile()) { 1889 DIFile F(S); 1890 Fn = F.getFilename(); 1891 Dir = F.getDirectory(); 1892 } else if (Scope.isSubprogram()) { 1893 DISubprogram SP(S); 1894 Fn = SP.getFilename(); 1895 Dir = SP.getDirectory(); 1896 } else if (Scope.isLexicalBlockFile()) { 1897 DILexicalBlockFile DBF(S); 1898 Fn = DBF.getFilename(); 1899 Dir = DBF.getDirectory(); 1900 } else if (Scope.isLexicalBlock()) { 1901 DILexicalBlock DB(S); 1902 Fn = DB.getFilename(); 1903 Dir = DB.getDirectory(); 1904 } else 1905 llvm_unreachable("Unexpected scope info"); 1906 1907 Src = getOrCreateSourceID(Fn, Dir, 1908 Asm->OutStreamer.getContext().getDwarfCompileUnitID()); 1909 } 1910 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0, 0, Fn); 1911} 1912 1913//===----------------------------------------------------------------------===// 1914// Emit Methods 1915//===----------------------------------------------------------------------===// 1916 1917// Compute the size and offset of a DIE. 1918unsigned 1919DwarfUnits::computeSizeAndOffset(DIE *Die, unsigned Offset) { 1920 // Get the children. 1921 const std::vector<DIE *> &Children = Die->getChildren(); 1922 1923 // Record the abbreviation. 1924 assignAbbrevNumber(Die->getAbbrev()); 1925 1926 // Get the abbreviation for this DIE. 1927 unsigned AbbrevNumber = Die->getAbbrevNumber(); 1928 const DIEAbbrev *Abbrev = Abbreviations->at(AbbrevNumber - 1); 1929 1930 // Set DIE offset 1931 Die->setOffset(Offset); 1932 1933 // Start the size with the size of abbreviation code. 1934 Offset += MCAsmInfo::getULEB128Size(AbbrevNumber); 1935 1936 const SmallVectorImpl<DIEValue*> &Values = Die->getValues(); 1937 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev->getData(); 1938 1939 // Size the DIE attribute values. 1940 for (unsigned i = 0, N = Values.size(); i < N; ++i) 1941 // Size attribute value. 1942 Offset += Values[i]->SizeOf(Asm, AbbrevData[i].getForm()); 1943 1944 // Size the DIE children if any. 1945 if (!Children.empty()) { 1946 assert(Abbrev->getChildrenFlag() == dwarf::DW_CHILDREN_yes && 1947 "Children flag not set"); 1948 1949 for (unsigned j = 0, M = Children.size(); j < M; ++j) 1950 Offset = computeSizeAndOffset(Children[j], Offset); 1951 1952 // End of children marker. 1953 Offset += sizeof(int8_t); 1954 } 1955 1956 Die->setSize(Offset - Die->getOffset()); 1957 return Offset; 1958} 1959 1960// Compute the size and offset of all the DIEs. 1961void DwarfUnits::computeSizeAndOffsets() { 1962 // Offset from the beginning of debug info section. 1963 for (SmallVectorImpl<CompileUnit *>::iterator I = CUs.begin(), 1964 E = CUs.end(); I != E; ++I) { 1965 unsigned Offset = 1966 sizeof(int32_t) + // Length of Compilation Unit Info 1967 sizeof(int16_t) + // DWARF version number 1968 sizeof(int32_t) + // Offset Into Abbrev. Section 1969 sizeof(int8_t); // Pointer Size (in bytes) 1970 computeSizeAndOffset((*I)->getCUDie(), Offset); 1971 } 1972} 1973 1974// Emit initial Dwarf sections with a label at the start of each one. 1975void DwarfDebug::emitSectionLabels() { 1976 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); 1977 1978 // Dwarf sections base addresses. 1979 DwarfInfoSectionSym = 1980 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info"); 1981 DwarfAbbrevSectionSym = 1982 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev"); 1983 if (useSplitDwarf()) 1984 DwarfAbbrevDWOSectionSym = 1985 emitSectionSym(Asm, TLOF.getDwarfAbbrevDWOSection(), 1986 "section_abbrev_dwo"); 1987 emitSectionSym(Asm, TLOF.getDwarfARangesSection()); 1988 1989 if (const MCSection *MacroInfo = TLOF.getDwarfMacroInfoSection()) 1990 emitSectionSym(Asm, MacroInfo); 1991 1992 DwarfLineSectionSym = 1993 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line"); 1994 emitSectionSym(Asm, TLOF.getDwarfLocSection()); 1995 if (GenerateGnuPubSections) { 1996 DwarfGnuPubNamesSectionSym = 1997 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection()); 1998 DwarfGnuPubTypesSectionSym = 1999 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection()); 2000 } else if (HasDwarfPubSections) { 2001 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection()); 2002 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection()); 2003 } 2004 2005 DwarfStrSectionSym = 2006 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string"); 2007 if (useSplitDwarf()) { 2008 DwarfStrDWOSectionSym = 2009 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string"); 2010 DwarfAddrSectionSym = 2011 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec"); 2012 } 2013 DwarfDebugRangeSectionSym = emitSectionSym(Asm, TLOF.getDwarfRangesSection(), 2014 "debug_range"); 2015 2016 DwarfDebugLocSectionSym = emitSectionSym(Asm, TLOF.getDwarfLocSection(), 2017 "section_debug_loc"); 2018 2019 TextSectionSym = emitSectionSym(Asm, TLOF.getTextSection(), "text_begin"); 2020 emitSectionSym(Asm, TLOF.getDataSection()); 2021} 2022 2023// Recursively emits a debug information entry. 2024void DwarfDebug::emitDIE(DIE *Die, std::vector<DIEAbbrev *> *Abbrevs) { 2025 // Get the abbreviation for this DIE. 2026 unsigned AbbrevNumber = Die->getAbbrevNumber(); 2027 const DIEAbbrev *Abbrev = Abbrevs->at(AbbrevNumber - 1); 2028 2029 // Emit the code (index) for the abbreviation. 2030 if (Asm->isVerbose()) 2031 Asm->OutStreamer.AddComment("Abbrev [" + Twine(AbbrevNumber) + "] 0x" + 2032 Twine::utohexstr(Die->getOffset()) + ":0x" + 2033 Twine::utohexstr(Die->getSize()) + " " + 2034 dwarf::TagString(Abbrev->getTag())); 2035 Asm->EmitULEB128(AbbrevNumber); 2036 2037 const SmallVectorImpl<DIEValue*> &Values = Die->getValues(); 2038 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev->getData(); 2039 2040 // Emit the DIE attribute values. 2041 for (unsigned i = 0, N = Values.size(); i < N; ++i) { 2042 unsigned Attr = AbbrevData[i].getAttribute(); 2043 unsigned Form = AbbrevData[i].getForm(); 2044 assert(Form && "Too many attributes for DIE (check abbreviation)"); 2045 2046 if (Asm->isVerbose()) 2047 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr)); 2048 2049 switch (Attr) { 2050 case dwarf::DW_AT_abstract_origin: { 2051 DIEEntry *E = cast<DIEEntry>(Values[i]); 2052 DIE *Origin = E->getEntry(); 2053 unsigned Addr = Origin->getOffset(); 2054 Asm->EmitInt32(Addr); 2055 break; 2056 } 2057 case dwarf::DW_AT_ranges: { 2058 // DW_AT_range Value encodes offset in debug_range section. 2059 DIEInteger *V = cast<DIEInteger>(Values[i]); 2060 2061 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) { 2062 Asm->EmitLabelPlusOffset(DwarfDebugRangeSectionSym, 2063 V->getValue(), 2064 4); 2065 } else { 2066 Asm->EmitLabelOffsetDifference(DwarfDebugRangeSectionSym, 2067 V->getValue(), 2068 DwarfDebugRangeSectionSym, 2069 4); 2070 } 2071 break; 2072 } 2073 case dwarf::DW_AT_location: { 2074 if (DIELabel *L = dyn_cast<DIELabel>(Values[i])) { 2075 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2076 Asm->EmitLabelReference(L->getValue(), 4); 2077 else 2078 Asm->EmitLabelDifference(L->getValue(), DwarfDebugLocSectionSym, 4); 2079 } else { 2080 Values[i]->EmitValue(Asm, Form); 2081 } 2082 break; 2083 } 2084 case dwarf::DW_AT_accessibility: { 2085 if (Asm->isVerbose()) { 2086 DIEInteger *V = cast<DIEInteger>(Values[i]); 2087 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(V->getValue())); 2088 } 2089 Values[i]->EmitValue(Asm, Form); 2090 break; 2091 } 2092 default: 2093 // Emit an attribute using the defined form. 2094 Values[i]->EmitValue(Asm, Form); 2095 break; 2096 } 2097 } 2098 2099 // Emit the DIE children if any. 2100 if (Abbrev->getChildrenFlag() == dwarf::DW_CHILDREN_yes) { 2101 const std::vector<DIE *> &Children = Die->getChildren(); 2102 2103 for (unsigned j = 0, M = Children.size(); j < M; ++j) 2104 emitDIE(Children[j], Abbrevs); 2105 2106 if (Asm->isVerbose()) 2107 Asm->OutStreamer.AddComment("End Of Children Mark"); 2108 Asm->EmitInt8(0); 2109 } 2110} 2111 2112// Emit the various dwarf units to the unit section USection with 2113// the abbreviations going into ASection. 2114void DwarfUnits::emitUnits(DwarfDebug *DD, 2115 const MCSection *USection, 2116 const MCSection *ASection, 2117 const MCSymbol *ASectionSym) { 2118 Asm->OutStreamer.SwitchSection(USection); 2119 for (SmallVectorImpl<CompileUnit *>::iterator I = CUs.begin(), 2120 E = CUs.end(); I != E; ++I) { 2121 CompileUnit *TheCU = *I; 2122 DIE *Die = TheCU->getCUDie(); 2123 2124 // Emit the compile units header. 2125 Asm->OutStreamer 2126 .EmitLabel(Asm->GetTempSymbol(USection->getLabelBeginName(), 2127 TheCU->getUniqueID())); 2128 2129 // Emit size of content not including length itself 2130 unsigned ContentSize = Die->getSize() + 2131 sizeof(int16_t) + // DWARF version number 2132 sizeof(int32_t) + // Offset Into Abbrev. Section 2133 sizeof(int8_t); // Pointer Size (in bytes) 2134 2135 Asm->OutStreamer.AddComment("Length of Compilation Unit Info"); 2136 Asm->EmitInt32(ContentSize); 2137 Asm->OutStreamer.AddComment("DWARF version number"); 2138 Asm->EmitInt16(DD->getDwarfVersion()); 2139 Asm->OutStreamer.AddComment("Offset Into Abbrev. Section"); 2140 Asm->EmitSectionOffset(Asm->GetTempSymbol(ASection->getLabelBeginName()), 2141 ASectionSym); 2142 Asm->OutStreamer.AddComment("Address Size (in bytes)"); 2143 Asm->EmitInt8(Asm->getDataLayout().getPointerSize()); 2144 2145 DD->emitDIE(Die, Abbreviations); 2146 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol(USection->getLabelEndName(), 2147 TheCU->getUniqueID())); 2148 } 2149} 2150 2151// Emit the debug info section. 2152void DwarfDebug::emitDebugInfo() { 2153 DwarfUnits &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; 2154 2155 Holder.emitUnits(this, Asm->getObjFileLowering().getDwarfInfoSection(), 2156 Asm->getObjFileLowering().getDwarfAbbrevSection(), 2157 DwarfAbbrevSectionSym); 2158} 2159 2160// Emit the abbreviation section. 2161void DwarfDebug::emitAbbreviations() { 2162 if (!useSplitDwarf()) 2163 emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection(), 2164 &Abbreviations); 2165 else 2166 emitSkeletonAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection()); 2167} 2168 2169void DwarfDebug::emitAbbrevs(const MCSection *Section, 2170 std::vector<DIEAbbrev *> *Abbrevs) { 2171 // Check to see if it is worth the effort. 2172 if (!Abbrevs->empty()) { 2173 // Start the debug abbrev section. 2174 Asm->OutStreamer.SwitchSection(Section); 2175 2176 MCSymbol *Begin = Asm->GetTempSymbol(Section->getLabelBeginName()); 2177 Asm->OutStreamer.EmitLabel(Begin); 2178 2179 // For each abbrevation. 2180 for (unsigned i = 0, N = Abbrevs->size(); i < N; ++i) { 2181 // Get abbreviation data 2182 const DIEAbbrev *Abbrev = Abbrevs->at(i); 2183 2184 // Emit the abbrevations code (base 1 index.) 2185 Asm->EmitULEB128(Abbrev->getNumber(), "Abbreviation Code"); 2186 2187 // Emit the abbreviations data. 2188 Abbrev->Emit(Asm); 2189 } 2190 2191 // Mark end of abbreviations. 2192 Asm->EmitULEB128(0, "EOM(3)"); 2193 2194 MCSymbol *End = Asm->GetTempSymbol(Section->getLabelEndName()); 2195 Asm->OutStreamer.EmitLabel(End); 2196 } 2197} 2198 2199// Emit the last address of the section and the end of the line matrix. 2200void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) { 2201 // Define last address of section. 2202 Asm->OutStreamer.AddComment("Extended Op"); 2203 Asm->EmitInt8(0); 2204 2205 Asm->OutStreamer.AddComment("Op size"); 2206 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1); 2207 Asm->OutStreamer.AddComment("DW_LNE_set_address"); 2208 Asm->EmitInt8(dwarf::DW_LNE_set_address); 2209 2210 Asm->OutStreamer.AddComment("Section end label"); 2211 2212 Asm->OutStreamer.EmitSymbolValue(Asm->GetTempSymbol("section_end",SectionEnd), 2213 Asm->getDataLayout().getPointerSize()); 2214 2215 // Mark end of matrix. 2216 Asm->OutStreamer.AddComment("DW_LNE_end_sequence"); 2217 Asm->EmitInt8(0); 2218 Asm->EmitInt8(1); 2219 Asm->EmitInt8(1); 2220} 2221 2222// Emit visible names into a hashed accelerator table section. 2223void DwarfDebug::emitAccelNames() { 2224 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2225 dwarf::DW_FORM_data4)); 2226 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2227 E = CUMap.end(); I != E; ++I) { 2228 CompileUnit *TheCU = I->second; 2229 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelNames(); 2230 for (StringMap<std::vector<DIE*> >::const_iterator 2231 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2232 StringRef Name = GI->getKey(); 2233 const std::vector<DIE *> &Entities = GI->second; 2234 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2235 DE = Entities.end(); DI != DE; ++DI) 2236 AT.AddName(Name, (*DI)); 2237 } 2238 } 2239 2240 AT.FinalizeTable(Asm, "Names"); 2241 Asm->OutStreamer.SwitchSection( 2242 Asm->getObjFileLowering().getDwarfAccelNamesSection()); 2243 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin"); 2244 Asm->OutStreamer.EmitLabel(SectionBegin); 2245 2246 // Emit the full data. 2247 AT.Emit(Asm, SectionBegin, &InfoHolder); 2248} 2249 2250// Emit objective C classes and categories into a hashed accelerator table 2251// section. 2252void DwarfDebug::emitAccelObjC() { 2253 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2254 dwarf::DW_FORM_data4)); 2255 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2256 E = CUMap.end(); I != E; ++I) { 2257 CompileUnit *TheCU = I->second; 2258 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelObjC(); 2259 for (StringMap<std::vector<DIE*> >::const_iterator 2260 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2261 StringRef Name = GI->getKey(); 2262 const std::vector<DIE *> &Entities = GI->second; 2263 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2264 DE = Entities.end(); DI != DE; ++DI) 2265 AT.AddName(Name, (*DI)); 2266 } 2267 } 2268 2269 AT.FinalizeTable(Asm, "ObjC"); 2270 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2271 .getDwarfAccelObjCSection()); 2272 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin"); 2273 Asm->OutStreamer.EmitLabel(SectionBegin); 2274 2275 // Emit the full data. 2276 AT.Emit(Asm, SectionBegin, &InfoHolder); 2277} 2278 2279// Emit namespace dies into a hashed accelerator table. 2280void DwarfDebug::emitAccelNamespaces() { 2281 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2282 dwarf::DW_FORM_data4)); 2283 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2284 E = CUMap.end(); I != E; ++I) { 2285 CompileUnit *TheCU = I->second; 2286 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelNamespace(); 2287 for (StringMap<std::vector<DIE*> >::const_iterator 2288 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2289 StringRef Name = GI->getKey(); 2290 const std::vector<DIE *> &Entities = GI->second; 2291 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2292 DE = Entities.end(); DI != DE; ++DI) 2293 AT.AddName(Name, (*DI)); 2294 } 2295 } 2296 2297 AT.FinalizeTable(Asm, "namespac"); 2298 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2299 .getDwarfAccelNamespaceSection()); 2300 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin"); 2301 Asm->OutStreamer.EmitLabel(SectionBegin); 2302 2303 // Emit the full data. 2304 AT.Emit(Asm, SectionBegin, &InfoHolder); 2305} 2306 2307// Emit type dies into a hashed accelerator table. 2308void DwarfDebug::emitAccelTypes() { 2309 std::vector<DwarfAccelTable::Atom> Atoms; 2310 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2311 dwarf::DW_FORM_data4)); 2312 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, 2313 dwarf::DW_FORM_data2)); 2314 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, 2315 dwarf::DW_FORM_data1)); 2316 DwarfAccelTable AT(Atoms); 2317 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2318 E = CUMap.end(); I != E; ++I) { 2319 CompileUnit *TheCU = I->second; 2320 const StringMap<std::vector<std::pair<DIE*, unsigned > > > &Names 2321 = TheCU->getAccelTypes(); 2322 for (StringMap<std::vector<std::pair<DIE*, unsigned> > >::const_iterator 2323 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2324 StringRef Name = GI->getKey(); 2325 const std::vector<std::pair<DIE *, unsigned> > &Entities = GI->second; 2326 for (std::vector<std::pair<DIE *, unsigned> >::const_iterator DI 2327 = Entities.begin(), DE = Entities.end(); DI !=DE; ++DI) 2328 AT.AddName(Name, (*DI).first, (*DI).second); 2329 } 2330 } 2331 2332 AT.FinalizeTable(Asm, "types"); 2333 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2334 .getDwarfAccelTypesSection()); 2335 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin"); 2336 Asm->OutStreamer.EmitLabel(SectionBegin); 2337 2338 // Emit the full data. 2339 AT.Emit(Asm, SectionBegin, &InfoHolder); 2340} 2341 2342// Public name handling. 2343// The format for the various pubnames: 2344// 2345// dwarf pubnames - offset/name pairs where the offset is the offset into the CU 2346// for the DIE that is named. 2347// 2348// gnu pubnames - offset/index value/name tuples where the offset is the offset 2349// into the CU and the index value is computed according to the type of value 2350// for the DIE that is named. 2351// 2352// For type units the offset is the offset of the skeleton DIE. For split dwarf 2353// it's the offset within the debug_info/debug_types dwo section, however, the 2354// reference in the pubname header doesn't change. 2355 2356/// computeIndexValue - Compute the gdb index value for the DIE and CU. 2357static dwarf::PubIndexEntryDescriptor computeIndexValue(CompileUnit *CU, 2358 DIE *Die) { 2359 dwarf::GDBIndexEntryLinkage Linkage = 2360 Die->findAttribute(dwarf::DW_AT_external) ? dwarf::GIEL_EXTERNAL 2361 : dwarf::GIEL_STATIC; 2362 2363 switch (Die->getTag()) { 2364 case dwarf::DW_TAG_class_type: 2365 case dwarf::DW_TAG_structure_type: 2366 case dwarf::DW_TAG_union_type: 2367 case dwarf::DW_TAG_enumeration_type: 2368 return dwarf::PubIndexEntryDescriptor( 2369 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus 2370 ? dwarf::GIEL_STATIC 2371 : dwarf::GIEL_EXTERNAL); 2372 case dwarf::DW_TAG_typedef: 2373 case dwarf::DW_TAG_base_type: 2374 case dwarf::DW_TAG_subrange_type: 2375 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC); 2376 case dwarf::DW_TAG_namespace: 2377 return dwarf::GIEK_TYPE; 2378 case dwarf::DW_TAG_subprogram: 2379 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage); 2380 case dwarf::DW_TAG_constant: 2381 case dwarf::DW_TAG_variable: 2382 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage); 2383 case dwarf::DW_TAG_enumerator: 2384 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, 2385 dwarf::GIEL_STATIC); 2386 default: 2387 return dwarf::GIEK_NONE; 2388 } 2389} 2390 2391/// emitDebugPubNames - Emit visible names into a debug pubnames section. 2392/// 2393void DwarfDebug::emitDebugPubNames(bool GnuStyle) { 2394 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2395 const MCSection *PSec = 2396 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection() 2397 : Asm->getObjFileLowering().getDwarfPubNamesSection(); 2398 2399 typedef DenseMap<const MDNode*, CompileUnit*> CUMapType; 2400 for (CUMapType::iterator I = CUMap.begin(), E = CUMap.end(); I != E; ++I) { 2401 CompileUnit *TheCU = I->second; 2402 unsigned ID = TheCU->getUniqueID(); 2403 2404 // Start the dwarf pubnames section. 2405 Asm->OutStreamer.SwitchSection(PSec); 2406 2407 // Emit a label so we can reference the beginning of this pubname section. 2408 if (GnuStyle) 2409 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("gnu_pubnames", 2410 TheCU->getUniqueID())); 2411 2412 // Emit the header. 2413 Asm->OutStreamer.AddComment("Length of Public Names Info"); 2414 Asm->EmitLabelDifference(Asm->GetTempSymbol("pubnames_end", ID), 2415 Asm->GetTempSymbol("pubnames_begin", ID), 4); 2416 2417 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("pubnames_begin", ID)); 2418 2419 Asm->OutStreamer.AddComment("DWARF Version"); 2420 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION); 2421 2422 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info"); 2423 Asm->EmitSectionOffset(Asm->GetTempSymbol(ISec->getLabelBeginName(), ID), 2424 DwarfInfoSectionSym); 2425 2426 Asm->OutStreamer.AddComment("Compilation Unit Length"); 2427 Asm->EmitLabelDifference(Asm->GetTempSymbol(ISec->getLabelEndName(), ID), 2428 Asm->GetTempSymbol(ISec->getLabelBeginName(), ID), 2429 4); 2430 2431 // Emit the pubnames for this compilation unit. 2432 const StringMap<DIE*> &Globals = TheCU->getGlobalNames(); 2433 for (StringMap<DIE*>::const_iterator 2434 GI = Globals.begin(), GE = Globals.end(); GI != GE; ++GI) { 2435 const char *Name = GI->getKeyData(); 2436 DIE *Entity = GI->second; 2437 2438 Asm->OutStreamer.AddComment("DIE offset"); 2439 Asm->EmitInt32(Entity->getOffset()); 2440 2441 if (GnuStyle) { 2442 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheCU, Entity); 2443 Asm->OutStreamer.AddComment( 2444 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " + 2445 dwarf::GDBIndexEntryLinkageString(Desc.Linkage)); 2446 Asm->EmitInt8(Desc.toBits()); 2447 } 2448 2449 if (Asm->isVerbose()) 2450 Asm->OutStreamer.AddComment("External Name"); 2451 Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength()+1)); 2452 } 2453 2454 Asm->OutStreamer.AddComment("End Mark"); 2455 Asm->EmitInt32(0); 2456 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("pubnames_end", ID)); 2457 } 2458} 2459 2460void DwarfDebug::emitDebugPubTypes(bool GnuStyle) { 2461 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2462 const MCSection *PSec = 2463 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection() 2464 : Asm->getObjFileLowering().getDwarfPubTypesSection(); 2465 2466 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2467 E = CUMap.end(); 2468 I != E; ++I) { 2469 CompileUnit *TheCU = I->second; 2470 // Start the dwarf pubtypes section. 2471 Asm->OutStreamer.SwitchSection(PSec); 2472 2473 // Emit a label so we can reference the beginning of this pubtype section. 2474 if (GnuStyle) 2475 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("gnu_pubtypes", 2476 TheCU->getUniqueID())); 2477 2478 // Emit the header. 2479 Asm->OutStreamer.AddComment("Length of Public Types Info"); 2480 Asm->EmitLabelDifference( 2481 Asm->GetTempSymbol("pubtypes_end", TheCU->getUniqueID()), 2482 Asm->GetTempSymbol("pubtypes_begin", TheCU->getUniqueID()), 4); 2483 2484 Asm->OutStreamer.EmitLabel( 2485 Asm->GetTempSymbol("pubtypes_begin", TheCU->getUniqueID())); 2486 2487 if (Asm->isVerbose()) 2488 Asm->OutStreamer.AddComment("DWARF Version"); 2489 Asm->EmitInt16(dwarf::DW_PUBTYPES_VERSION); 2490 2491 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info"); 2492 Asm->EmitSectionOffset( 2493 Asm->GetTempSymbol(ISec->getLabelBeginName(), TheCU->getUniqueID()), 2494 DwarfInfoSectionSym); 2495 2496 Asm->OutStreamer.AddComment("Compilation Unit Length"); 2497 Asm->EmitLabelDifference( 2498 Asm->GetTempSymbol(ISec->getLabelEndName(), TheCU->getUniqueID()), 2499 Asm->GetTempSymbol(ISec->getLabelBeginName(), TheCU->getUniqueID()), 4); 2500 2501 // Emit the pubtypes. 2502 const StringMap<DIE *> &Globals = TheCU->getGlobalTypes(); 2503 for (StringMap<DIE *>::const_iterator GI = Globals.begin(), 2504 GE = Globals.end(); 2505 GI != GE; ++GI) { 2506 const char *Name = GI->getKeyData(); 2507 DIE *Entity = GI->second; 2508 2509 if (Asm->isVerbose()) 2510 Asm->OutStreamer.AddComment("DIE offset"); 2511 Asm->EmitInt32(Entity->getOffset()); 2512 2513 if (GnuStyle) { 2514 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheCU, Entity); 2515 Asm->OutStreamer.AddComment( 2516 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " + 2517 dwarf::GDBIndexEntryLinkageString(Desc.Linkage)); 2518 Asm->EmitInt8(Desc.toBits()); 2519 } 2520 2521 if (Asm->isVerbose()) 2522 Asm->OutStreamer.AddComment("External Name"); 2523 2524 // Emit the name with a terminating null byte. 2525 Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength() + 1)); 2526 } 2527 2528 Asm->OutStreamer.AddComment("End Mark"); 2529 Asm->EmitInt32(0); 2530 Asm->OutStreamer.EmitLabel( 2531 Asm->GetTempSymbol("pubtypes_end", TheCU->getUniqueID())); 2532 } 2533} 2534 2535// Emit strings into a string section. 2536void DwarfUnits::emitStrings(const MCSection *StrSection, 2537 const MCSection *OffsetSection = NULL, 2538 const MCSymbol *StrSecSym = NULL) { 2539 2540 if (StringPool.empty()) return; 2541 2542 // Start the dwarf str section. 2543 Asm->OutStreamer.SwitchSection(StrSection); 2544 2545 // Get all of the string pool entries and put them in an array by their ID so 2546 // we can sort them. 2547 SmallVector<std::pair<unsigned, 2548 StringMapEntry<std::pair<MCSymbol*, unsigned> >*>, 64> Entries; 2549 2550 for (StringMap<std::pair<MCSymbol*, unsigned> >::iterator 2551 I = StringPool.begin(), E = StringPool.end(); 2552 I != E; ++I) 2553 Entries.push_back(std::make_pair(I->second.second, &*I)); 2554 2555 array_pod_sort(Entries.begin(), Entries.end()); 2556 2557 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2558 // Emit a label for reference from debug information entries. 2559 Asm->OutStreamer.EmitLabel(Entries[i].second->getValue().first); 2560 2561 // Emit the string itself with a terminating null byte. 2562 Asm->OutStreamer.EmitBytes(StringRef(Entries[i].second->getKeyData(), 2563 Entries[i].second->getKeyLength()+1)); 2564 } 2565 2566 // If we've got an offset section go ahead and emit that now as well. 2567 if (OffsetSection) { 2568 Asm->OutStreamer.SwitchSection(OffsetSection); 2569 unsigned offset = 0; 2570 unsigned size = 4; // FIXME: DWARF64 is 8. 2571 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2572 Asm->OutStreamer.EmitIntValue(offset, size); 2573 offset += Entries[i].second->getKeyLength() + 1; 2574 } 2575 } 2576} 2577 2578// Emit strings into a string section. 2579void DwarfUnits::emitAddresses(const MCSection *AddrSection) { 2580 2581 if (AddressPool.empty()) return; 2582 2583 // Start the dwarf addr section. 2584 Asm->OutStreamer.SwitchSection(AddrSection); 2585 2586 // Order the address pool entries by ID 2587 SmallVector<const MCExpr *, 64> Entries(AddressPool.size()); 2588 2589 for (DenseMap<const MCExpr *, unsigned>::iterator I = AddressPool.begin(), 2590 E = AddressPool.end(); 2591 I != E; ++I) 2592 Entries[I->second] = I->first; 2593 2594 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2595 // Emit an expression for reference from debug information entries. 2596 if (const MCExpr *Expr = Entries[i]) 2597 Asm->OutStreamer.EmitValue(Expr, Asm->getDataLayout().getPointerSize()); 2598 else 2599 Asm->OutStreamer.EmitIntValue(0, Asm->getDataLayout().getPointerSize()); 2600 } 2601 2602} 2603 2604// Emit visible names into a debug str section. 2605void DwarfDebug::emitDebugStr() { 2606 DwarfUnits &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; 2607 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection()); 2608} 2609 2610// Emit locations into the debug loc section. 2611void DwarfDebug::emitDebugLoc() { 2612 if (DotDebugLocEntries.empty()) 2613 return; 2614 2615 for (SmallVectorImpl<DotDebugLocEntry>::iterator 2616 I = DotDebugLocEntries.begin(), E = DotDebugLocEntries.end(); 2617 I != E; ++I) { 2618 DotDebugLocEntry &Entry = *I; 2619 if (I + 1 != DotDebugLocEntries.end()) 2620 Entry.Merge(I+1); 2621 } 2622 2623 // Start the dwarf loc section. 2624 Asm->OutStreamer.SwitchSection( 2625 Asm->getObjFileLowering().getDwarfLocSection()); 2626 unsigned char Size = Asm->getDataLayout().getPointerSize(); 2627 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", 0)); 2628 unsigned index = 1; 2629 for (SmallVectorImpl<DotDebugLocEntry>::iterator 2630 I = DotDebugLocEntries.begin(), E = DotDebugLocEntries.end(); 2631 I != E; ++I, ++index) { 2632 DotDebugLocEntry &Entry = *I; 2633 if (Entry.isMerged()) continue; 2634 if (Entry.isEmpty()) { 2635 Asm->OutStreamer.EmitIntValue(0, Size); 2636 Asm->OutStreamer.EmitIntValue(0, Size); 2637 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", index)); 2638 } else { 2639 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size); 2640 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size); 2641 DIVariable DV(Entry.getVariable()); 2642 Asm->OutStreamer.AddComment("Loc expr size"); 2643 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol(); 2644 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol(); 2645 Asm->EmitLabelDifference(end, begin, 2); 2646 Asm->OutStreamer.EmitLabel(begin); 2647 if (Entry.isInt()) { 2648 DIBasicType BTy(DV.getType()); 2649 if (BTy.Verify() && 2650 (BTy.getEncoding() == dwarf::DW_ATE_signed 2651 || BTy.getEncoding() == dwarf::DW_ATE_signed_char)) { 2652 Asm->OutStreamer.AddComment("DW_OP_consts"); 2653 Asm->EmitInt8(dwarf::DW_OP_consts); 2654 Asm->EmitSLEB128(Entry.getInt()); 2655 } else { 2656 Asm->OutStreamer.AddComment("DW_OP_constu"); 2657 Asm->EmitInt8(dwarf::DW_OP_constu); 2658 Asm->EmitULEB128(Entry.getInt()); 2659 } 2660 } else if (Entry.isLocation()) { 2661 MachineLocation Loc = Entry.getLoc(); 2662 if (!DV.hasComplexAddress()) 2663 // Regular entry. 2664 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2665 else { 2666 // Complex address entry. 2667 unsigned N = DV.getNumAddrElements(); 2668 unsigned i = 0; 2669 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) { 2670 if (Loc.getOffset()) { 2671 i = 2; 2672 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2673 Asm->OutStreamer.AddComment("DW_OP_deref"); 2674 Asm->EmitInt8(dwarf::DW_OP_deref); 2675 Asm->OutStreamer.AddComment("DW_OP_plus_uconst"); 2676 Asm->EmitInt8(dwarf::DW_OP_plus_uconst); 2677 Asm->EmitSLEB128(DV.getAddrElement(1)); 2678 } else { 2679 // If first address element is OpPlus then emit 2680 // DW_OP_breg + Offset instead of DW_OP_reg + Offset. 2681 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1)); 2682 Asm->EmitDwarfRegOp(TLoc, DV.isIndirect()); 2683 i = 2; 2684 } 2685 } else { 2686 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2687 } 2688 2689 // Emit remaining complex address elements. 2690 for (; i < N; ++i) { 2691 uint64_t Element = DV.getAddrElement(i); 2692 if (Element == DIBuilder::OpPlus) { 2693 Asm->EmitInt8(dwarf::DW_OP_plus_uconst); 2694 Asm->EmitULEB128(DV.getAddrElement(++i)); 2695 } else if (Element == DIBuilder::OpDeref) { 2696 if (!Loc.isReg()) 2697 Asm->EmitInt8(dwarf::DW_OP_deref); 2698 } else 2699 llvm_unreachable("unknown Opcode found in complex address"); 2700 } 2701 } 2702 } 2703 // else ... ignore constant fp. There is not any good way to 2704 // to represent them here in dwarf. 2705 Asm->OutStreamer.EmitLabel(end); 2706 } 2707 } 2708} 2709 2710struct SymbolCUSorter { 2711 SymbolCUSorter(const MCStreamer &s) : Streamer(s) {} 2712 const MCStreamer &Streamer; 2713 2714 bool operator() (const SymbolCU &A, const SymbolCU &B) { 2715 unsigned IA = A.Sym ? Streamer.GetSymbolOrder(A.Sym) : 0; 2716 unsigned IB = B.Sym ? Streamer.GetSymbolOrder(B.Sym) : 0; 2717 2718 // Symbols with no order assigned should be placed at the end. 2719 // (e.g. section end labels) 2720 if (IA == 0) 2721 IA = (unsigned)(-1); 2722 if (IB == 0) 2723 IB = (unsigned)(-1); 2724 return IA < IB; 2725 } 2726}; 2727 2728static bool CUSort(const CompileUnit *A, const CompileUnit *B) { 2729 return (A->getUniqueID() < B->getUniqueID()); 2730} 2731 2732struct ArangeSpan { 2733 const MCSymbol *Start, *End; 2734}; 2735 2736// Emit a debug aranges section, containing a CU lookup for any 2737// address we can tie back to a CU. 2738void DwarfDebug::emitDebugARanges() { 2739 // Start the dwarf aranges section. 2740 Asm->OutStreamer 2741 .SwitchSection(Asm->getObjFileLowering().getDwarfARangesSection()); 2742 2743 typedef DenseMap<CompileUnit *, std::vector<ArangeSpan> > SpansType; 2744 2745 SpansType Spans; 2746 2747 // Build a list of sections used. 2748 std::vector<const MCSection *> Sections; 2749 for (SectionMapType::iterator it = SectionMap.begin(); it != SectionMap.end(); 2750 it++) { 2751 const MCSection *Section = it->first; 2752 Sections.push_back(Section); 2753 } 2754 2755 // Sort the sections into order. 2756 // This is only done to ensure consistent output order across different runs. 2757 std::sort(Sections.begin(), Sections.end(), SectionSort); 2758 2759 // Build a set of address spans, sorted by CU. 2760 for (size_t SecIdx=0;SecIdx<Sections.size();SecIdx++) { 2761 const MCSection *Section = Sections[SecIdx]; 2762 SmallVector<SymbolCU, 8> &List = SectionMap[Section]; 2763 if (List.size() < 2) 2764 continue; 2765 2766 // Sort the symbols by offset within the section. 2767 SymbolCUSorter sorter(Asm->OutStreamer); 2768 std::sort(List.begin(), List.end(), sorter); 2769 2770 // If we have no section (e.g. common), just write out 2771 // individual spans for each symbol. 2772 if (Section == NULL) { 2773 for (size_t n = 0; n < List.size(); n++) { 2774 const SymbolCU &Cur = List[n]; 2775 2776 ArangeSpan Span; 2777 Span.Start = Cur.Sym; 2778 Span.End = NULL; 2779 if (Cur.CU) 2780 Spans[Cur.CU].push_back(Span); 2781 } 2782 } else { 2783 // Build spans between each label. 2784 const MCSymbol *StartSym = List[0].Sym; 2785 for (size_t n = 1; n < List.size(); n++) { 2786 const SymbolCU &Prev = List[n - 1]; 2787 const SymbolCU &Cur = List[n]; 2788 2789 // Try and build the longest span we can within the same CU. 2790 if (Cur.CU != Prev.CU) { 2791 ArangeSpan Span; 2792 Span.Start = StartSym; 2793 Span.End = Cur.Sym; 2794 Spans[Prev.CU].push_back(Span); 2795 StartSym = Cur.Sym; 2796 } 2797 } 2798 } 2799 } 2800 2801 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2802 unsigned PtrSize = Asm->getDataLayout().getPointerSize(); 2803 2804 // Build a list of CUs used. 2805 std::vector<CompileUnit *> CUs; 2806 for (SpansType::iterator it = Spans.begin(); it != Spans.end(); it++) { 2807 CompileUnit *CU = it->first; 2808 CUs.push_back(CU); 2809 } 2810 2811 // Sort the CU list (again, to ensure consistent output order). 2812 std::sort(CUs.begin(), CUs.end(), CUSort); 2813 2814 // Emit an arange table for each CU we used. 2815 for (size_t CUIdx=0;CUIdx<CUs.size();CUIdx++) { 2816 CompileUnit *CU = CUs[CUIdx]; 2817 std::vector<ArangeSpan> &List = Spans[CU]; 2818 2819 // Emit size of content not including length itself. 2820 unsigned ContentSize 2821 = sizeof(int16_t) // DWARF ARange version number 2822 + sizeof(int32_t) // Offset of CU in the .debug_info section 2823 + sizeof(int8_t) // Pointer Size (in bytes) 2824 + sizeof(int8_t); // Segment Size (in bytes) 2825 2826 unsigned TupleSize = PtrSize * 2; 2827 2828 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple. 2829 unsigned Padding = 0; 2830 while (((sizeof(int32_t) + ContentSize + Padding) % TupleSize) != 0) 2831 Padding++; 2832 2833 ContentSize += Padding; 2834 ContentSize += (List.size() + 1) * TupleSize; 2835 2836 // For each compile unit, write the list of spans it covers. 2837 Asm->OutStreamer.AddComment("Length of ARange Set"); 2838 Asm->EmitInt32(ContentSize); 2839 Asm->OutStreamer.AddComment("DWARF Arange version number"); 2840 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION); 2841 Asm->OutStreamer.AddComment("Offset Into Debug Info Section"); 2842 Asm->EmitSectionOffset( 2843 Asm->GetTempSymbol(ISec->getLabelBeginName(), CU->getUniqueID()), 2844 DwarfInfoSectionSym); 2845 Asm->OutStreamer.AddComment("Address Size (in bytes)"); 2846 Asm->EmitInt8(PtrSize); 2847 Asm->OutStreamer.AddComment("Segment Size (in bytes)"); 2848 Asm->EmitInt8(0); 2849 2850 for (unsigned n = 0; n < Padding; n++) 2851 Asm->EmitInt8(0xff); 2852 2853 for (unsigned n = 0; n < List.size(); n++) { 2854 const ArangeSpan &Span = List[n]; 2855 Asm->EmitLabelReference(Span.Start, PtrSize); 2856 2857 // Calculate the size as being from the span start to it's end. 2858 if (Span.End) { 2859 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize); 2860 } else { 2861 // For symbols without an end marker (e.g. common), we 2862 // write a single arange entry containing just that one symbol. 2863 uint64_t Size = SymSize[Span.Start]; 2864 if (Size == 0) 2865 Size = 1; 2866 2867 Asm->OutStreamer.EmitIntValue(Size, PtrSize); 2868 } 2869 } 2870 2871 Asm->OutStreamer.AddComment("ARange terminator"); 2872 Asm->OutStreamer.EmitIntValue(0, PtrSize); 2873 Asm->OutStreamer.EmitIntValue(0, PtrSize); 2874 } 2875} 2876 2877// Emit visible names into a debug ranges section. 2878void DwarfDebug::emitDebugRanges() { 2879 // Start the dwarf ranges section. 2880 Asm->OutStreamer 2881 .SwitchSection(Asm->getObjFileLowering().getDwarfRangesSection()); 2882 unsigned char Size = Asm->getDataLayout().getPointerSize(); 2883 for (SmallVectorImpl<const MCSymbol *>::iterator 2884 I = DebugRangeSymbols.begin(), E = DebugRangeSymbols.end(); 2885 I != E; ++I) { 2886 if (*I) 2887 Asm->OutStreamer.EmitSymbolValue(const_cast<MCSymbol*>(*I), Size); 2888 else 2889 Asm->OutStreamer.EmitIntValue(0, Size); 2890 } 2891} 2892 2893// Emit visible names into a debug macinfo section. 2894void DwarfDebug::emitDebugMacInfo() { 2895 if (const MCSection *LineInfo = 2896 Asm->getObjFileLowering().getDwarfMacroInfoSection()) { 2897 // Start the dwarf macinfo section. 2898 Asm->OutStreamer.SwitchSection(LineInfo); 2899 } 2900} 2901 2902// DWARF5 Experimental Separate Dwarf emitters. 2903 2904// This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list, 2905// DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id, 2906// DW_AT_ranges_base, DW_AT_addr_base. 2907CompileUnit *DwarfDebug::constructSkeletonCU(const CompileUnit *CU) { 2908 2909 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit); 2910 CompileUnit *NewCU = new CompileUnit(CU->getUniqueID(), Die, CU->getNode(), 2911 Asm, this, &SkeletonHolder); 2912 2913 NewCU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name, 2914 DICompileUnit(CU->getNode()).getSplitDebugFilename()); 2915 2916 // Relocate to the beginning of the addr_base section, else 0 for the 2917 // beginning of the one for this compile unit. 2918 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2919 NewCU->addLabel(Die, dwarf::DW_AT_GNU_addr_base, dwarf::DW_FORM_sec_offset, 2920 DwarfAddrSectionSym); 2921 else 2922 NewCU->addUInt(Die, dwarf::DW_AT_GNU_addr_base, 2923 dwarf::DW_FORM_sec_offset, 0); 2924 2925 // 2.17.1 requires that we use DW_AT_low_pc for a single entry point 2926 // into an entity. We're using 0, or a NULL label for this. 2927 NewCU->addUInt(Die, dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr, 0); 2928 2929 // DW_AT_stmt_list is a offset of line number information for this 2930 // compile unit in debug_line section. 2931 // FIXME: Should handle multiple compile units. 2932 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2933 NewCU->addLabel(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 2934 DwarfLineSectionSym); 2935 else 2936 NewCU->addUInt(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 0); 2937 2938 if (!CompilationDir.empty()) 2939 NewCU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir); 2940 2941 // Flags to let the linker know we have emitted new style pubnames. 2942 if (GenerateGnuPubSections) { 2943 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2944 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_sec_offset, 2945 Asm->GetTempSymbol("gnu_pubnames", NewCU->getUniqueID())); 2946 else 2947 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_data4, 2948 Asm->GetTempSymbol("gnu_pubnames", NewCU->getUniqueID()), 2949 DwarfGnuPubNamesSectionSym); 2950 2951 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2952 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_sec_offset, 2953 Asm->GetTempSymbol("gnu_pubtypes", NewCU->getUniqueID())); 2954 else 2955 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_data4, 2956 Asm->GetTempSymbol("gnu_pubtypes", NewCU->getUniqueID()), 2957 DwarfGnuPubTypesSectionSym); 2958 } 2959 2960 // Flag if we've emitted any ranges and their location for the compile unit. 2961 if (DebugRangeSymbols.size()) { 2962 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2963 NewCU->addLabel(Die, dwarf::DW_AT_GNU_ranges_base, 2964 dwarf::DW_FORM_sec_offset, DwarfDebugRangeSectionSym); 2965 else 2966 NewCU->addUInt(Die, dwarf::DW_AT_GNU_ranges_base, dwarf::DW_FORM_data4, 2967 0); 2968 } 2969 2970 SkeletonHolder.addUnit(NewCU); 2971 SkeletonCUs.push_back(NewCU); 2972 2973 return NewCU; 2974} 2975 2976void DwarfDebug::emitSkeletonAbbrevs(const MCSection *Section) { 2977 assert(useSplitDwarf() && "No split dwarf debug info?"); 2978 emitAbbrevs(Section, &SkeletonAbbrevs); 2979} 2980 2981// Emit the .debug_info.dwo section for separated dwarf. This contains the 2982// compile units that would normally be in debug_info. 2983void DwarfDebug::emitDebugInfoDWO() { 2984 assert(useSplitDwarf() && "No split dwarf debug info?"); 2985 InfoHolder.emitUnits(this, Asm->getObjFileLowering().getDwarfInfoDWOSection(), 2986 Asm->getObjFileLowering().getDwarfAbbrevDWOSection(), 2987 DwarfAbbrevDWOSectionSym); 2988} 2989 2990// Emit the .debug_abbrev.dwo section for separated dwarf. This contains the 2991// abbreviations for the .debug_info.dwo section. 2992void DwarfDebug::emitDebugAbbrevDWO() { 2993 assert(useSplitDwarf() && "No split dwarf?"); 2994 emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection(), 2995 &Abbreviations); 2996} 2997 2998// Emit the .debug_str.dwo section for separated dwarf. This contains the 2999// string section and is identical in format to traditional .debug_str 3000// sections. 3001void DwarfDebug::emitDebugStrDWO() { 3002 assert(useSplitDwarf() && "No split dwarf?"); 3003 const MCSection *OffSec = Asm->getObjFileLowering() 3004 .getDwarfStrOffDWOSection(); 3005 const MCSymbol *StrSym = DwarfStrSectionSym; 3006 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(), 3007 OffSec, StrSym); 3008} 3009