DwarfDebug.cpp revision 7b641815290f34f0212e4cb7b26ed1708270cb97
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 = SPCU->createAndAddDIE(dwarf::DW_TAG_subprogram, *SPCU->getCUDie()); 382 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_abstract_origin, AbsSPDIE); 383 } else { 384 DISubprogram SPDecl = SP.getFunctionDeclaration(); 385 if (!SPDecl.isSubprogram()) { 386 // There is not any need to generate specification DIE for a function 387 // defined at compile unit level. If a function is defined inside another 388 // function then gdb prefers the definition at top level and but does not 389 // expect specification DIE in parent function. So avoid creating 390 // specification DIE for a function defined inside a function. 391 DIScope SPContext = resolve(SP.getContext()); 392 if (SP.isDefinition() && !SPContext.isCompileUnit() && 393 !SPContext.isFile() && 394 !isSubprogramContext(SPContext)) { 395 SPCU->addFlag(SPDie, dwarf::DW_AT_declaration); 396 397 // Add arguments. 398 DICompositeType SPTy = SP.getType(); 399 DIArray Args = SPTy.getTypeArray(); 400 uint16_t SPTag = SPTy.getTag(); 401 if (SPTag == dwarf::DW_TAG_subroutine_type) 402 for (unsigned i = 1, N = Args.getNumElements(); i < N; ++i) { 403 DIE *Arg = 404 SPCU->createAndAddDIE(dwarf::DW_TAG_formal_parameter, *SPDie); 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 } 412 DIE *SPDeclDie = SPDie; 413 SPDie = 414 SPCU->createAndAddDIE(dwarf::DW_TAG_subprogram, *SPCU->getCUDie()); 415 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_specification, SPDeclDie); 416 } 417 } 418 } 419 420 SPCU->addLabelAddress(SPDie, dwarf::DW_AT_low_pc, 421 Asm->GetTempSymbol("func_begin", 422 Asm->getFunctionNumber())); 423 SPCU->addLabelAddress(SPDie, dwarf::DW_AT_high_pc, 424 Asm->GetTempSymbol("func_end", 425 Asm->getFunctionNumber())); 426 const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo(); 427 MachineLocation Location(RI->getFrameRegister(*Asm->MF)); 428 SPCU->addAddress(SPDie, dwarf::DW_AT_frame_base, Location); 429 430 // Add name to the name table, we do this here because we're guaranteed 431 // to have concrete versions of our DW_TAG_subprogram nodes. 432 addSubprogramNames(SPCU, SP, SPDie); 433 434 return SPDie; 435} 436 437/// Check whether we should create a DIE for the given Scope, return true 438/// if we don't create a DIE (the corresponding DIE is null). 439bool DwarfDebug::isLexicalScopeDIENull(LexicalScope *Scope) { 440 if (Scope->isAbstractScope()) 441 return false; 442 443 // We don't create a DIE if there is no Range. 444 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 445 if (Ranges.empty()) 446 return true; 447 448 if (Ranges.size() > 1) 449 return false; 450 451 // We don't create a DIE if we have a single Range and the end label 452 // is null. 453 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 454 MCSymbol *End = getLabelAfterInsn(RI->second); 455 return !End; 456} 457 458// Construct new DW_TAG_lexical_block for this scope and attach 459// DW_AT_low_pc/DW_AT_high_pc labels. 460DIE *DwarfDebug::constructLexicalScopeDIE(CompileUnit *TheCU, 461 LexicalScope *Scope) { 462 if (isLexicalScopeDIENull(Scope)) 463 return 0; 464 465 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_lexical_block); 466 if (Scope->isAbstractScope()) 467 return ScopeDIE; 468 469 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 470 // If we have multiple ranges, emit them into the range section. 471 if (Ranges.size() > 1) { 472 // .debug_range section has not been laid out yet. Emit offset in 473 // .debug_range as a uint, size 4, for now. emitDIE will handle 474 // DW_AT_ranges appropriately. 475 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_ranges, dwarf::DW_FORM_data4, 476 DebugRangeSymbols.size() 477 * Asm->getDataLayout().getPointerSize()); 478 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 479 RE = Ranges.end(); RI != RE; ++RI) { 480 DebugRangeSymbols.push_back(getLabelBeforeInsn(RI->first)); 481 DebugRangeSymbols.push_back(getLabelAfterInsn(RI->second)); 482 } 483 484 // Terminate the range list. 485 DebugRangeSymbols.push_back(NULL); 486 DebugRangeSymbols.push_back(NULL); 487 return ScopeDIE; 488 } 489 490 // Construct the address range for this DIE. 491 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 492 MCSymbol *Start = getLabelBeforeInsn(RI->first); 493 MCSymbol *End = getLabelAfterInsn(RI->second); 494 assert(End && "End label should not be null!"); 495 496 assert(Start->isDefined() && "Invalid starting label for an inlined scope!"); 497 assert(End->isDefined() && "Invalid end label for an inlined scope!"); 498 499 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_low_pc, Start); 500 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_high_pc, End); 501 502 return ScopeDIE; 503} 504 505// This scope represents inlined body of a function. Construct DIE to 506// represent this concrete inlined copy of the function. 507DIE *DwarfDebug::constructInlinedScopeDIE(CompileUnit *TheCU, 508 LexicalScope *Scope) { 509 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 510 assert(Ranges.empty() == false && 511 "LexicalScope does not have instruction markers!"); 512 513 if (!Scope->getScopeNode()) 514 return NULL; 515 DIScope DS(Scope->getScopeNode()); 516 DISubprogram InlinedSP = getDISubprogram(DS); 517 DIE *OriginDIE = TheCU->getDIE(InlinedSP); 518 if (!OriginDIE) { 519 DEBUG(dbgs() << "Unable to find original DIE for an inlined subprogram."); 520 return NULL; 521 } 522 523 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_inlined_subroutine); 524 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_abstract_origin, OriginDIE); 525 526 if (Ranges.size() > 1) { 527 // .debug_range section has not been laid out yet. Emit offset in 528 // .debug_range as a uint, size 4, for now. emitDIE will handle 529 // DW_AT_ranges appropriately. 530 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_ranges, dwarf::DW_FORM_data4, 531 DebugRangeSymbols.size() 532 * Asm->getDataLayout().getPointerSize()); 533 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 534 RE = Ranges.end(); RI != RE; ++RI) { 535 DebugRangeSymbols.push_back(getLabelBeforeInsn(RI->first)); 536 DebugRangeSymbols.push_back(getLabelAfterInsn(RI->second)); 537 } 538 DebugRangeSymbols.push_back(NULL); 539 DebugRangeSymbols.push_back(NULL); 540 } else { 541 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 542 MCSymbol *StartLabel = getLabelBeforeInsn(RI->first); 543 MCSymbol *EndLabel = getLabelAfterInsn(RI->second); 544 545 if (StartLabel == 0 || EndLabel == 0) 546 llvm_unreachable("Unexpected Start and End labels for an inlined scope!"); 547 548 assert(StartLabel->isDefined() && 549 "Invalid starting label for an inlined scope!"); 550 assert(EndLabel->isDefined() && "Invalid end label for an inlined scope!"); 551 552 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_low_pc, StartLabel); 553 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_high_pc, EndLabel); 554 } 555 556 InlinedSubprogramDIEs.insert(OriginDIE); 557 558 // Add the call site information to the DIE. 559 DILocation DL(Scope->getInlinedAt()); 560 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_file, None, 561 getOrCreateSourceID(DL.getFilename(), DL.getDirectory(), 562 TheCU->getUniqueID())); 563 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_line, None, DL.getLineNumber()); 564 565 // Add name to the name table, we do this here because we're guaranteed 566 // to have concrete versions of our DW_TAG_inlined_subprogram nodes. 567 addSubprogramNames(TheCU, InlinedSP, ScopeDIE); 568 569 return ScopeDIE; 570} 571 572DIE *DwarfDebug::createScopeChildrenDIE(CompileUnit *TheCU, LexicalScope *Scope, 573 SmallVectorImpl<DIE*> &Children) { 574 DIE *ObjectPointer = NULL; 575 576 // Collect arguments for current function. 577 if (LScopes.isCurrentFunctionScope(Scope)) 578 for (unsigned i = 0, N = CurrentFnArguments.size(); i < N; ++i) 579 if (DbgVariable *ArgDV = CurrentFnArguments[i]) 580 if (DIE *Arg = 581 TheCU->constructVariableDIE(*ArgDV, Scope->isAbstractScope())) { 582 Children.push_back(Arg); 583 if (ArgDV->isObjectPointer()) ObjectPointer = Arg; 584 } 585 586 // Collect lexical scope children first. 587 const SmallVectorImpl<DbgVariable *> &Variables =ScopeVariables.lookup(Scope); 588 for (unsigned i = 0, N = Variables.size(); i < N; ++i) 589 if (DIE *Variable = 590 TheCU->constructVariableDIE(*Variables[i], Scope->isAbstractScope())) { 591 Children.push_back(Variable); 592 if (Variables[i]->isObjectPointer()) ObjectPointer = Variable; 593 } 594 const SmallVectorImpl<LexicalScope *> &Scopes = Scope->getChildren(); 595 for (unsigned j = 0, M = Scopes.size(); j < M; ++j) 596 if (DIE *Nested = constructScopeDIE(TheCU, Scopes[j])) 597 Children.push_back(Nested); 598 return ObjectPointer; 599} 600 601// Construct a DIE for this scope. 602DIE *DwarfDebug::constructScopeDIE(CompileUnit *TheCU, LexicalScope *Scope) { 603 if (!Scope || !Scope->getScopeNode()) 604 return NULL; 605 606 DIScope DS(Scope->getScopeNode()); 607 608 SmallVector<DIE *, 8> Children; 609 DIE *ObjectPointer = NULL; 610 bool ChildrenCreated = false; 611 612 // We try to create the scope DIE first, then the children DIEs. This will 613 // avoid creating un-used children then removing them later when we find out 614 // the scope DIE is null. 615 DIE *ScopeDIE = NULL; 616 if (Scope->getInlinedAt()) 617 ScopeDIE = constructInlinedScopeDIE(TheCU, Scope); 618 else if (DS.isSubprogram()) { 619 ProcessedSPNodes.insert(DS); 620 if (Scope->isAbstractScope()) { 621 ScopeDIE = TheCU->getDIE(DS); 622 // Note down abstract DIE. 623 if (ScopeDIE) 624 AbstractSPDies.insert(std::make_pair(DS, ScopeDIE)); 625 } 626 else 627 ScopeDIE = updateSubprogramScopeDIE(TheCU, DS); 628 } 629 else { 630 // Early exit when we know the scope DIE is going to be null. 631 if (isLexicalScopeDIENull(Scope)) 632 return NULL; 633 634 // We create children here when we know the scope DIE is not going to be 635 // null and the children will be added to the scope DIE. 636 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children); 637 ChildrenCreated = true; 638 639 // There is no need to emit empty lexical block DIE. 640 std::pair<ImportedEntityMap::const_iterator, 641 ImportedEntityMap::const_iterator> Range = std::equal_range( 642 ScopesWithImportedEntities.begin(), ScopesWithImportedEntities.end(), 643 std::pair<const MDNode *, const MDNode *>(DS, (const MDNode*)0), 644 less_first()); 645 if (Children.empty() && Range.first == Range.second) 646 return NULL; 647 ScopeDIE = constructLexicalScopeDIE(TheCU, Scope); 648 assert(ScopeDIE && "Scope DIE should not be null."); 649 for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second; 650 ++i) 651 constructImportedEntityDIE(TheCU, i->second, ScopeDIE); 652 } 653 654 if (!ScopeDIE) { 655 assert(Children.empty() && 656 "We create children only when the scope DIE is not null."); 657 return NULL; 658 } 659 if (!ChildrenCreated) 660 // We create children when the scope DIE is not null. 661 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children); 662 663 // Add children 664 for (SmallVectorImpl<DIE *>::iterator I = Children.begin(), 665 E = Children.end(); I != E; ++I) 666 ScopeDIE->addChild(*I); 667 668 if (DS.isSubprogram() && ObjectPointer != NULL) 669 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, ObjectPointer); 670 671 if (DS.isSubprogram()) 672 TheCU->addPubTypes(DISubprogram(DS)); 673 674 return ScopeDIE; 675} 676 677// Look up the source id with the given directory and source file names. 678// If none currently exists, create a new id and insert it in the 679// SourceIds map. This can update DirectoryNames and SourceFileNames maps 680// as well. 681unsigned DwarfDebug::getOrCreateSourceID(StringRef FileName, 682 StringRef DirName, unsigned CUID) { 683 // If we use .loc in assembly, we can't separate .file entries according to 684 // compile units. Thus all files will belong to the default compile unit. 685 686 // FIXME: add a better feature test than hasRawTextSupport. Even better, 687 // extend .file to support this. 688 if (Asm->TM.hasMCUseLoc() && Asm->OutStreamer.hasRawTextSupport()) 689 CUID = 0; 690 691 // If FE did not provide a file name, then assume stdin. 692 if (FileName.empty()) 693 return getOrCreateSourceID("<stdin>", StringRef(), CUID); 694 695 // TODO: this might not belong here. See if we can factor this better. 696 if (DirName == CompilationDir) 697 DirName = ""; 698 699 // FileIDCUMap stores the current ID for the given compile unit. 700 unsigned SrcId = FileIDCUMap[CUID] + 1; 701 702 // We look up the CUID/file/dir by concatenating them with a zero byte. 703 SmallString<128> NamePair; 704 NamePair += utostr(CUID); 705 NamePair += '\0'; 706 NamePair += DirName; 707 NamePair += '\0'; // Zero bytes are not allowed in paths. 708 NamePair += FileName; 709 710 StringMapEntry<unsigned> &Ent = SourceIdMap.GetOrCreateValue(NamePair, SrcId); 711 if (Ent.getValue() != SrcId) 712 return Ent.getValue(); 713 714 FileIDCUMap[CUID] = SrcId; 715 // Print out a .file directive to specify files for .loc directives. 716 Asm->OutStreamer.EmitDwarfFileDirective(SrcId, DirName, FileName, CUID); 717 718 return SrcId; 719} 720 721// Create new CompileUnit for the given metadata node with tag 722// DW_TAG_compile_unit. 723CompileUnit *DwarfDebug::constructCompileUnit(const MDNode *N) { 724 DICompileUnit DIUnit(N); 725 StringRef FN = DIUnit.getFilename(); 726 CompilationDir = DIUnit.getDirectory(); 727 728 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit); 729 CompileUnit *NewCU = 730 new CompileUnit(GlobalCUIndexCount++, Die, N, Asm, this, &InfoHolder); 731 732 FileIDCUMap[NewCU->getUniqueID()] = 0; 733 // Call this to emit a .file directive if it wasn't emitted for the source 734 // file this CU comes from yet. 735 getOrCreateSourceID(FN, CompilationDir, NewCU->getUniqueID()); 736 737 NewCU->addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer()); 738 NewCU->addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2, 739 DIUnit.getLanguage()); 740 NewCU->addString(Die, dwarf::DW_AT_name, FN); 741 742 // 2.17.1 requires that we use DW_AT_low_pc for a single entry point 743 // into an entity. We're using 0 (or a NULL label) for this. For 744 // split dwarf it's in the skeleton CU so omit it here. 745 if (!useSplitDwarf()) 746 NewCU->addLabelAddress(Die, dwarf::DW_AT_low_pc, NULL); 747 748 // Define start line table label for each Compile Unit. 749 MCSymbol *LineTableStartSym = Asm->GetTempSymbol("line_table_start", 750 NewCU->getUniqueID()); 751 Asm->OutStreamer.getContext().setMCLineTableSymbol(LineTableStartSym, 752 NewCU->getUniqueID()); 753 754 // Use a single line table if we are using .loc and generating assembly. 755 bool UseTheFirstCU = 756 (Asm->TM.hasMCUseLoc() && Asm->OutStreamer.hasRawTextSupport()) || 757 (NewCU->getUniqueID() == 0); 758 759 if (!useSplitDwarf()) { 760 // DW_AT_stmt_list is a offset of line number information for this 761 // compile unit in debug_line section. For split dwarf this is 762 // left in the skeleton CU and so not included. 763 // The line table entries are not always emitted in assembly, so it 764 // is not okay to use line_table_start here. 765 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 766 NewCU->addLabel(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 767 UseTheFirstCU ? Asm->GetTempSymbol("section_line") 768 : LineTableStartSym); 769 else if (UseTheFirstCU) 770 NewCU->addUInt(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4, 0); 771 else 772 NewCU->addDelta(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4, 773 LineTableStartSym, DwarfLineSectionSym); 774 775 // If we're using split dwarf the compilation dir is going to be in the 776 // skeleton CU and so we don't need to duplicate it here. 777 if (!CompilationDir.empty()) 778 NewCU->addString(Die, dwarf::DW_AT_comp_dir, CompilationDir); 779 780 // Flags to let the linker know we have emitted new style pubnames. Only 781 // emit it here if we don't have a skeleton CU for split dwarf. 782 if (GenerateGnuPubSections) { 783 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 784 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubnames, 785 dwarf::DW_FORM_sec_offset, 786 Asm->GetTempSymbol("gnu_pubnames", 787 NewCU->getUniqueID())); 788 else 789 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_data4, 790 Asm->GetTempSymbol("gnu_pubnames", 791 NewCU->getUniqueID()), 792 DwarfGnuPubNamesSectionSym); 793 794 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 795 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubtypes, 796 dwarf::DW_FORM_sec_offset, 797 Asm->GetTempSymbol("gnu_pubtypes", 798 NewCU->getUniqueID())); 799 else 800 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_data4, 801 Asm->GetTempSymbol("gnu_pubtypes", 802 NewCU->getUniqueID()), 803 DwarfGnuPubTypesSectionSym); 804 } 805 } 806 807 if (DIUnit.isOptimized()) 808 NewCU->addFlag(Die, dwarf::DW_AT_APPLE_optimized); 809 810 StringRef Flags = DIUnit.getFlags(); 811 if (!Flags.empty()) 812 NewCU->addString(Die, dwarf::DW_AT_APPLE_flags, Flags); 813 814 if (unsigned RVer = DIUnit.getRunTimeVersion()) 815 NewCU->addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers, 816 dwarf::DW_FORM_data1, RVer); 817 818 if (!FirstCU) 819 FirstCU = NewCU; 820 821 InfoHolder.addUnit(NewCU); 822 823 CUMap.insert(std::make_pair(N, NewCU)); 824 CUDieMap.insert(std::make_pair(Die, NewCU)); 825 return NewCU; 826} 827 828// Construct subprogram DIE. 829void DwarfDebug::constructSubprogramDIE(CompileUnit *TheCU, const MDNode *N) { 830 // FIXME: We should only call this routine once, however, during LTO if a 831 // program is defined in multiple CUs we could end up calling it out of 832 // beginModule as we walk the CUs. 833 834 CompileUnit *&CURef = SPMap[N]; 835 if (CURef) 836 return; 837 CURef = TheCU; 838 839 DISubprogram SP(N); 840 if (!SP.isDefinition()) 841 // This is a method declaration which will be handled while constructing 842 // class type. 843 return; 844 845 DIE *SubprogramDie = TheCU->getOrCreateSubprogramDIE(SP); 846 847 // Expose as a global name. 848 TheCU->addGlobalName(SP.getName(), SubprogramDie, resolve(SP.getContext())); 849} 850 851void DwarfDebug::constructImportedEntityDIE(CompileUnit *TheCU, 852 const MDNode *N) { 853 DIImportedEntity Module(N); 854 if (!Module.Verify()) 855 return; 856 if (DIE *D = TheCU->getOrCreateContextDIE(Module.getContext())) 857 constructImportedEntityDIE(TheCU, Module, D); 858} 859 860void DwarfDebug::constructImportedEntityDIE(CompileUnit *TheCU, const MDNode *N, 861 DIE *Context) { 862 DIImportedEntity Module(N); 863 if (!Module.Verify()) 864 return; 865 return constructImportedEntityDIE(TheCU, Module, Context); 866} 867 868void DwarfDebug::constructImportedEntityDIE(CompileUnit *TheCU, 869 const DIImportedEntity &Module, 870 DIE *Context) { 871 assert(Module.Verify() && 872 "Use one of the MDNode * overloads to handle invalid metadata"); 873 assert(Context && "Should always have a context for an imported_module"); 874 DIE *IMDie = new DIE(Module.getTag()); 875 TheCU->insertDIE(Module, IMDie); 876 DIE *EntityDie; 877 DIDescriptor Entity = Module.getEntity(); 878 if (Entity.isNameSpace()) 879 EntityDie = TheCU->getOrCreateNameSpace(DINameSpace(Entity)); 880 else if (Entity.isSubprogram()) 881 EntityDie = TheCU->getOrCreateSubprogramDIE(DISubprogram(Entity)); 882 else if (Entity.isType()) 883 EntityDie = TheCU->getOrCreateTypeDIE(DIType(Entity)); 884 else 885 EntityDie = TheCU->getDIE(Entity); 886 unsigned FileID = getOrCreateSourceID(Module.getContext().getFilename(), 887 Module.getContext().getDirectory(), 888 TheCU->getUniqueID()); 889 TheCU->addUInt(IMDie, dwarf::DW_AT_decl_file, None, FileID); 890 TheCU->addUInt(IMDie, dwarf::DW_AT_decl_line, None, Module.getLineNumber()); 891 TheCU->addDIEEntry(IMDie, dwarf::DW_AT_import, EntityDie); 892 StringRef Name = Module.getName(); 893 if (!Name.empty()) 894 TheCU->addString(IMDie, dwarf::DW_AT_name, Name); 895 Context->addChild(IMDie); 896} 897 898// Emit all Dwarf sections that should come prior to the content. Create 899// global DIEs and emit initial debug info sections. This is invoked by 900// the target AsmPrinter. 901void DwarfDebug::beginModule() { 902 if (DisableDebugInfoPrinting) 903 return; 904 905 const Module *M = MMI->getModule(); 906 907 // If module has named metadata anchors then use them, otherwise scan the 908 // module using debug info finder to collect debug info. 909 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu"); 910 if (!CU_Nodes) 911 return; 912 TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes); 913 914 // Emit initial sections so we can reference labels later. 915 emitSectionLabels(); 916 917 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) { 918 DICompileUnit CUNode(CU_Nodes->getOperand(i)); 919 CompileUnit *CU = constructCompileUnit(CUNode); 920 DIArray ImportedEntities = CUNode.getImportedEntities(); 921 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i) 922 ScopesWithImportedEntities.push_back(std::make_pair( 923 DIImportedEntity(ImportedEntities.getElement(i)).getContext(), 924 ImportedEntities.getElement(i))); 925 std::sort(ScopesWithImportedEntities.begin(), 926 ScopesWithImportedEntities.end(), less_first()); 927 DIArray GVs = CUNode.getGlobalVariables(); 928 for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i) 929 CU->createGlobalVariableDIE(GVs.getElement(i)); 930 DIArray SPs = CUNode.getSubprograms(); 931 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) 932 constructSubprogramDIE(CU, SPs.getElement(i)); 933 DIArray EnumTypes = CUNode.getEnumTypes(); 934 for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i) 935 CU->getOrCreateTypeDIE(EnumTypes.getElement(i)); 936 DIArray RetainedTypes = CUNode.getRetainedTypes(); 937 for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i) 938 CU->getOrCreateTypeDIE(RetainedTypes.getElement(i)); 939 // Emit imported_modules last so that the relevant context is already 940 // available. 941 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i) 942 constructImportedEntityDIE(CU, ImportedEntities.getElement(i)); 943 } 944 945 // Tell MMI that we have debug info. 946 MMI->setDebugInfoAvailability(true); 947 948 // Prime section data. 949 SectionMap[Asm->getObjFileLowering().getTextSection()]; 950} 951 952// Attach DW_AT_inline attribute with inlined subprogram DIEs. 953void DwarfDebug::computeInlinedDIEs() { 954 // Attach DW_AT_inline attribute with inlined subprogram DIEs. 955 for (SmallPtrSet<DIE *, 4>::iterator AI = InlinedSubprogramDIEs.begin(), 956 AE = InlinedSubprogramDIEs.end(); AI != AE; ++AI) { 957 DIE *ISP = *AI; 958 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined); 959 } 960 for (DenseMap<const MDNode *, DIE *>::iterator AI = AbstractSPDies.begin(), 961 AE = AbstractSPDies.end(); AI != AE; ++AI) { 962 DIE *ISP = AI->second; 963 if (InlinedSubprogramDIEs.count(ISP)) 964 continue; 965 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined); 966 } 967} 968 969// Collect info for variables that were optimized out. 970void DwarfDebug::collectDeadVariables() { 971 const Module *M = MMI->getModule(); 972 973 if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) { 974 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) { 975 DICompileUnit TheCU(CU_Nodes->getOperand(i)); 976 DIArray Subprograms = TheCU.getSubprograms(); 977 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) { 978 DISubprogram SP(Subprograms.getElement(i)); 979 if (ProcessedSPNodes.count(SP) != 0) 980 continue; 981 if (!SP.isSubprogram()) 982 continue; 983 if (!SP.isDefinition()) 984 continue; 985 DIArray Variables = SP.getVariables(); 986 if (Variables.getNumElements() == 0) 987 continue; 988 989 // Construct subprogram DIE and add variables DIEs. 990 CompileUnit *SPCU = CUMap.lookup(TheCU); 991 assert(SPCU && "Unable to find Compile Unit!"); 992 // FIXME: See the comment in constructSubprogramDIE about duplicate 993 // subprogram DIEs. 994 constructSubprogramDIE(SPCU, SP); 995 DIE *SPDIE = SPCU->getDIE(SP); 996 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) { 997 DIVariable DV(Variables.getElement(vi)); 998 if (!DV.isVariable()) 999 continue; 1000 DbgVariable NewVar(DV, NULL, this); 1001 if (DIE *VariableDIE = 1002 SPCU->constructVariableDIE(NewVar, false)) 1003 SPDIE->addChild(VariableDIE); 1004 } 1005 } 1006 } 1007 } 1008} 1009 1010// Type Signature [7.27] and ODR Hash code. 1011 1012/// \brief Grabs the string in whichever attribute is passed in and returns 1013/// a reference to it. Returns "" if the attribute doesn't exist. 1014static StringRef getDIEStringAttr(DIE *Die, unsigned Attr) { 1015 DIEValue *V = Die->findAttribute(Attr); 1016 1017 if (DIEString *S = dyn_cast_or_null<DIEString>(V)) 1018 return S->getString(); 1019 1020 return StringRef(""); 1021} 1022 1023/// Return true if the current DIE is contained within an anonymous namespace. 1024static bool isContainedInAnonNamespace(DIE *Die) { 1025 DIE *Parent = Die->getParent(); 1026 1027 while (Parent) { 1028 if (Parent->getTag() == dwarf::DW_TAG_namespace && 1029 getDIEStringAttr(Parent, dwarf::DW_AT_name) == "") 1030 return true; 1031 Parent = Parent->getParent(); 1032 } 1033 1034 return false; 1035} 1036 1037/// Test if the current CU language is C++ and that we have 1038/// a named type that is not contained in an anonymous namespace. 1039static bool shouldAddODRHash(CompileUnit *CU, DIE *Die) { 1040 return CU->getLanguage() == dwarf::DW_LANG_C_plus_plus && 1041 getDIEStringAttr(Die, dwarf::DW_AT_name) != "" && 1042 !isContainedInAnonNamespace(Die); 1043} 1044 1045void DwarfDebug::finalizeModuleInfo() { 1046 // Collect info for variables that were optimized out. 1047 collectDeadVariables(); 1048 1049 // Attach DW_AT_inline attribute with inlined subprogram DIEs. 1050 computeInlinedDIEs(); 1051 1052 // Split out type units and conditionally add an ODR tag to the split 1053 // out type. 1054 // FIXME: Do type splitting. 1055 for (unsigned i = 0, e = TypeUnits.size(); i != e; ++i) { 1056 DIE *Die = TypeUnits[i]; 1057 DIEHash Hash; 1058 // If we've requested ODR hashes and it's applicable for an ODR hash then 1059 // add the ODR signature now. 1060 // FIXME: This should be added onto the type unit, not the type, but this 1061 // works as an intermediate stage. 1062 if (GenerateODRHash && shouldAddODRHash(CUMap.begin()->second, Die)) 1063 CUMap.begin()->second->addUInt(Die, dwarf::DW_AT_GNU_odr_signature, 1064 dwarf::DW_FORM_data8, 1065 Hash.computeDIEODRSignature(*Die)); 1066 } 1067 1068 // Handle anything that needs to be done on a per-cu basis. 1069 for (DenseMap<const MDNode *, CompileUnit *>::iterator CUI = CUMap.begin(), 1070 CUE = CUMap.end(); 1071 CUI != CUE; ++CUI) { 1072 CompileUnit *TheCU = CUI->second; 1073 // Emit DW_AT_containing_type attribute to connect types with their 1074 // vtable holding type. 1075 TheCU->constructContainingTypeDIEs(); 1076 1077 // If we're splitting the dwarf out now that we've got the entire 1078 // CU then construct a skeleton CU based upon it. 1079 if (useSplitDwarf()) { 1080 uint64_t ID = 0; 1081 if (GenerateCUHash) { 1082 DIEHash CUHash; 1083 ID = CUHash.computeCUSignature(*TheCU->getCUDie()); 1084 } 1085 // This should be a unique identifier when we want to build .dwp files. 1086 TheCU->addUInt(TheCU->getCUDie(), dwarf::DW_AT_GNU_dwo_id, 1087 dwarf::DW_FORM_data8, ID); 1088 // Now construct the skeleton CU associated. 1089 CompileUnit *SkCU = constructSkeletonCU(TheCU); 1090 // This should be a unique identifier when we want to build .dwp files. 1091 SkCU->addUInt(SkCU->getCUDie(), dwarf::DW_AT_GNU_dwo_id, 1092 dwarf::DW_FORM_data8, ID); 1093 } 1094 } 1095 1096 // Compute DIE offsets and sizes. 1097 InfoHolder.computeSizeAndOffsets(); 1098 if (useSplitDwarf()) 1099 SkeletonHolder.computeSizeAndOffsets(); 1100} 1101 1102void DwarfDebug::endSections() { 1103 // Filter labels by section. 1104 for (size_t n = 0; n < ArangeLabels.size(); n++) { 1105 const SymbolCU &SCU = ArangeLabels[n]; 1106 if (SCU.Sym->isInSection()) { 1107 // Make a note of this symbol and it's section. 1108 const MCSection *Section = &SCU.Sym->getSection(); 1109 if (!Section->getKind().isMetadata()) 1110 SectionMap[Section].push_back(SCU); 1111 } else { 1112 // Some symbols (e.g. common/bss on mach-o) can have no section but still 1113 // appear in the output. This sucks as we rely on sections to build 1114 // arange spans. We can do it without, but it's icky. 1115 SectionMap[NULL].push_back(SCU); 1116 } 1117 } 1118 1119 // Build a list of sections used. 1120 std::vector<const MCSection *> Sections; 1121 for (SectionMapType::iterator it = SectionMap.begin(); it != SectionMap.end(); 1122 it++) { 1123 const MCSection *Section = it->first; 1124 Sections.push_back(Section); 1125 } 1126 1127 // Sort the sections into order. 1128 // This is only done to ensure consistent output order across different runs. 1129 std::sort(Sections.begin(), Sections.end(), SectionSort); 1130 1131 // Add terminating symbols for each section. 1132 for (unsigned ID=0;ID<Sections.size();ID++) { 1133 const MCSection *Section = Sections[ID]; 1134 MCSymbol *Sym = NULL; 1135 1136 if (Section) { 1137 // We can't call MCSection::getLabelEndName, as it's only safe to do so 1138 // if we know the section name up-front. For user-created sections, the resulting 1139 // label may not be valid to use as a label. (section names can use a greater 1140 // set of characters on some systems) 1141 Sym = Asm->GetTempSymbol("debug_end", ID); 1142 Asm->OutStreamer.SwitchSection(Section); 1143 Asm->OutStreamer.EmitLabel(Sym); 1144 } 1145 1146 // Insert a final terminator. 1147 SectionMap[Section].push_back(SymbolCU(NULL, Sym)); 1148 } 1149} 1150 1151// Emit all Dwarf sections that should come after the content. 1152void DwarfDebug::endModule() { 1153 1154 if (!FirstCU) return; 1155 1156 // End any existing sections. 1157 // TODO: Does this need to happen? 1158 endSections(); 1159 1160 // Finalize the debug info for the module. 1161 finalizeModuleInfo(); 1162 1163 if (!useSplitDwarf()) { 1164 emitDebugStr(); 1165 1166 // Emit all the DIEs into a debug info section. 1167 emitDebugInfo(); 1168 1169 // Corresponding abbreviations into a abbrev section. 1170 emitAbbreviations(); 1171 1172 // Emit info into a debug loc section. 1173 emitDebugLoc(); 1174 1175 // Emit info into a debug aranges section. 1176 emitDebugARanges(); 1177 1178 // Emit info into a debug ranges section. 1179 emitDebugRanges(); 1180 1181 // Emit info into a debug macinfo section. 1182 emitDebugMacInfo(); 1183 1184 } else { 1185 // TODO: Fill this in for separated debug sections and separate 1186 // out information into new sections. 1187 emitDebugStr(); 1188 if (useSplitDwarf()) 1189 emitDebugStrDWO(); 1190 1191 // Emit the debug info section and compile units. 1192 emitDebugInfo(); 1193 emitDebugInfoDWO(); 1194 1195 // Corresponding abbreviations into a abbrev section. 1196 emitAbbreviations(); 1197 emitDebugAbbrevDWO(); 1198 1199 // Emit info into a debug loc section. 1200 emitDebugLoc(); 1201 1202 // Emit info into a debug aranges section. 1203 emitDebugARanges(); 1204 1205 // Emit info into a debug ranges section. 1206 emitDebugRanges(); 1207 1208 // Emit info into a debug macinfo section. 1209 emitDebugMacInfo(); 1210 1211 // Emit DWO addresses. 1212 InfoHolder.emitAddresses(Asm->getObjFileLowering().getDwarfAddrSection()); 1213 1214 } 1215 1216 // Emit info into the dwarf accelerator table sections. 1217 if (useDwarfAccelTables()) { 1218 emitAccelNames(); 1219 emitAccelObjC(); 1220 emitAccelNamespaces(); 1221 emitAccelTypes(); 1222 } 1223 1224 // Emit the pubnames and pubtypes sections if requested. 1225 if (HasDwarfPubSections) { 1226 emitDebugPubNames(GenerateGnuPubSections); 1227 emitDebugPubTypes(GenerateGnuPubSections); 1228 } 1229 1230 // clean up. 1231 SPMap.clear(); 1232 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 1233 E = CUMap.end(); I != E; ++I) 1234 delete I->second; 1235 1236 for (SmallVectorImpl<CompileUnit *>::iterator I = SkeletonCUs.begin(), 1237 E = SkeletonCUs.end(); I != E; ++I) 1238 delete *I; 1239 1240 // Reset these for the next Module if we have one. 1241 FirstCU = NULL; 1242} 1243 1244// Find abstract variable, if any, associated with Var. 1245DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &DV, 1246 DebugLoc ScopeLoc) { 1247 LLVMContext &Ctx = DV->getContext(); 1248 // More then one inlined variable corresponds to one abstract variable. 1249 DIVariable Var = cleanseInlinedVariable(DV, Ctx); 1250 DbgVariable *AbsDbgVariable = AbstractVariables.lookup(Var); 1251 if (AbsDbgVariable) 1252 return AbsDbgVariable; 1253 1254 LexicalScope *Scope = LScopes.findAbstractScope(ScopeLoc.getScope(Ctx)); 1255 if (!Scope) 1256 return NULL; 1257 1258 AbsDbgVariable = new DbgVariable(Var, NULL, this); 1259 addScopeVariable(Scope, AbsDbgVariable); 1260 AbstractVariables[Var] = AbsDbgVariable; 1261 return AbsDbgVariable; 1262} 1263 1264// If Var is a current function argument then add it to CurrentFnArguments list. 1265bool DwarfDebug::addCurrentFnArgument(const MachineFunction *MF, 1266 DbgVariable *Var, LexicalScope *Scope) { 1267 if (!LScopes.isCurrentFunctionScope(Scope)) 1268 return false; 1269 DIVariable DV = Var->getVariable(); 1270 if (DV.getTag() != dwarf::DW_TAG_arg_variable) 1271 return false; 1272 unsigned ArgNo = DV.getArgNumber(); 1273 if (ArgNo == 0) 1274 return false; 1275 1276 size_t Size = CurrentFnArguments.size(); 1277 if (Size == 0) 1278 CurrentFnArguments.resize(MF->getFunction()->arg_size()); 1279 // llvm::Function argument size is not good indicator of how many 1280 // arguments does the function have at source level. 1281 if (ArgNo > Size) 1282 CurrentFnArguments.resize(ArgNo * 2); 1283 CurrentFnArguments[ArgNo - 1] = Var; 1284 return true; 1285} 1286 1287// Collect variable information from side table maintained by MMI. 1288void 1289DwarfDebug::collectVariableInfoFromMMITable(const MachineFunction *MF, 1290 SmallPtrSet<const MDNode *, 16> &Processed) { 1291 MachineModuleInfo::VariableDbgInfoMapTy &VMap = MMI->getVariableDbgInfo(); 1292 for (MachineModuleInfo::VariableDbgInfoMapTy::iterator VI = VMap.begin(), 1293 VE = VMap.end(); VI != VE; ++VI) { 1294 const MDNode *Var = VI->first; 1295 if (!Var) continue; 1296 Processed.insert(Var); 1297 DIVariable DV(Var); 1298 const std::pair<unsigned, DebugLoc> &VP = VI->second; 1299 1300 LexicalScope *Scope = LScopes.findLexicalScope(VP.second); 1301 1302 // If variable scope is not found then skip this variable. 1303 if (Scope == 0) 1304 continue; 1305 1306 DbgVariable *AbsDbgVariable = findAbstractVariable(DV, VP.second); 1307 DbgVariable *RegVar = new DbgVariable(DV, AbsDbgVariable, this); 1308 RegVar->setFrameIndex(VP.first); 1309 if (!addCurrentFnArgument(MF, RegVar, Scope)) 1310 addScopeVariable(Scope, RegVar); 1311 if (AbsDbgVariable) 1312 AbsDbgVariable->setFrameIndex(VP.first); 1313 } 1314} 1315 1316// Return true if debug value, encoded by DBG_VALUE instruction, is in a 1317// defined reg. 1318static bool isDbgValueInDefinedReg(const MachineInstr *MI) { 1319 assert(MI->isDebugValue() && "Invalid DBG_VALUE machine instruction!"); 1320 return MI->getNumOperands() == 3 && 1321 MI->getOperand(0).isReg() && MI->getOperand(0).getReg() && 1322 (MI->getOperand(1).isImm() || 1323 (MI->getOperand(1).isReg() && MI->getOperand(1).getReg() == 0U)); 1324} 1325 1326// Get .debug_loc entry for the instruction range starting at MI. 1327static DotDebugLocEntry getDebugLocEntry(AsmPrinter *Asm, 1328 const MCSymbol *FLabel, 1329 const MCSymbol *SLabel, 1330 const MachineInstr *MI) { 1331 const MDNode *Var = MI->getOperand(MI->getNumOperands() - 1).getMetadata(); 1332 1333 assert(MI->getNumOperands() == 3); 1334 if (MI->getOperand(0).isReg()) { 1335 MachineLocation MLoc; 1336 // If the second operand is an immediate, this is a 1337 // register-indirect address. 1338 if (!MI->getOperand(1).isImm()) 1339 MLoc.set(MI->getOperand(0).getReg()); 1340 else 1341 MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm()); 1342 return DotDebugLocEntry(FLabel, SLabel, MLoc, Var); 1343 } 1344 if (MI->getOperand(0).isImm()) 1345 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getImm()); 1346 if (MI->getOperand(0).isFPImm()) 1347 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getFPImm()); 1348 if (MI->getOperand(0).isCImm()) 1349 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getCImm()); 1350 1351 llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!"); 1352} 1353 1354// Find variables for each lexical scope. 1355void 1356DwarfDebug::collectVariableInfo(const MachineFunction *MF, 1357 SmallPtrSet<const MDNode *, 16> &Processed) { 1358 1359 // Grab the variable info that was squirreled away in the MMI side-table. 1360 collectVariableInfoFromMMITable(MF, Processed); 1361 1362 for (SmallVectorImpl<const MDNode*>::const_iterator 1363 UVI = UserVariables.begin(), UVE = UserVariables.end(); UVI != UVE; 1364 ++UVI) { 1365 const MDNode *Var = *UVI; 1366 if (Processed.count(Var)) 1367 continue; 1368 1369 // History contains relevant DBG_VALUE instructions for Var and instructions 1370 // clobbering it. 1371 SmallVectorImpl<const MachineInstr*> &History = DbgValues[Var]; 1372 if (History.empty()) 1373 continue; 1374 const MachineInstr *MInsn = History.front(); 1375 1376 DIVariable DV(Var); 1377 LexicalScope *Scope = NULL; 1378 if (DV.getTag() == dwarf::DW_TAG_arg_variable && 1379 DISubprogram(DV.getContext()).describes(MF->getFunction())) 1380 Scope = LScopes.getCurrentFunctionScope(); 1381 else if (MDNode *IA = DV.getInlinedAt()) 1382 Scope = LScopes.findInlinedScope(DebugLoc::getFromDILocation(IA)); 1383 else 1384 Scope = LScopes.findLexicalScope(cast<MDNode>(DV->getOperand(1))); 1385 // If variable scope is not found then skip this variable. 1386 if (!Scope) 1387 continue; 1388 1389 Processed.insert(DV); 1390 assert(MInsn->isDebugValue() && "History must begin with debug value"); 1391 DbgVariable *AbsVar = findAbstractVariable(DV, MInsn->getDebugLoc()); 1392 DbgVariable *RegVar = new DbgVariable(DV, AbsVar, this); 1393 if (!addCurrentFnArgument(MF, RegVar, Scope)) 1394 addScopeVariable(Scope, RegVar); 1395 if (AbsVar) 1396 AbsVar->setMInsn(MInsn); 1397 1398 // Simplify ranges that are fully coalesced. 1399 if (History.size() <= 1 || (History.size() == 2 && 1400 MInsn->isIdenticalTo(History.back()))) { 1401 RegVar->setMInsn(MInsn); 1402 continue; 1403 } 1404 1405 // Handle multiple DBG_VALUE instructions describing one variable. 1406 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size()); 1407 1408 for (SmallVectorImpl<const MachineInstr*>::const_iterator 1409 HI = History.begin(), HE = History.end(); HI != HE; ++HI) { 1410 const MachineInstr *Begin = *HI; 1411 assert(Begin->isDebugValue() && "Invalid History entry"); 1412 1413 // Check if DBG_VALUE is truncating a range. 1414 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() 1415 && !Begin->getOperand(0).getReg()) 1416 continue; 1417 1418 // Compute the range for a register location. 1419 const MCSymbol *FLabel = getLabelBeforeInsn(Begin); 1420 const MCSymbol *SLabel = 0; 1421 1422 if (HI + 1 == HE) 1423 // If Begin is the last instruction in History then its value is valid 1424 // until the end of the function. 1425 SLabel = FunctionEndSym; 1426 else { 1427 const MachineInstr *End = HI[1]; 1428 DEBUG(dbgs() << "DotDebugLoc Pair:\n" 1429 << "\t" << *Begin << "\t" << *End << "\n"); 1430 if (End->isDebugValue()) 1431 SLabel = getLabelBeforeInsn(End); 1432 else { 1433 // End is a normal instruction clobbering the range. 1434 SLabel = getLabelAfterInsn(End); 1435 assert(SLabel && "Forgot label after clobber instruction"); 1436 ++HI; 1437 } 1438 } 1439 1440 // The value is valid until the next DBG_VALUE or clobber. 1441 DotDebugLocEntries.push_back(getDebugLocEntry(Asm, FLabel, SLabel, 1442 Begin)); 1443 } 1444 DotDebugLocEntries.push_back(DotDebugLocEntry()); 1445 } 1446 1447 // Collect info for variables that were optimized out. 1448 LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); 1449 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables(); 1450 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) { 1451 DIVariable DV(Variables.getElement(i)); 1452 if (!DV || !DV.isVariable() || !Processed.insert(DV)) 1453 continue; 1454 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext())) 1455 addScopeVariable(Scope, new DbgVariable(DV, NULL, this)); 1456 } 1457} 1458 1459// Return Label preceding the instruction. 1460MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) { 1461 MCSymbol *Label = LabelsBeforeInsn.lookup(MI); 1462 assert(Label && "Didn't insert label before instruction"); 1463 return Label; 1464} 1465 1466// Return Label immediately following the instruction. 1467MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) { 1468 return LabelsAfterInsn.lookup(MI); 1469} 1470 1471// Process beginning of an instruction. 1472void DwarfDebug::beginInstruction(const MachineInstr *MI) { 1473 // Check if source location changes, but ignore DBG_VALUE locations. 1474 if (!MI->isDebugValue()) { 1475 DebugLoc DL = MI->getDebugLoc(); 1476 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) { 1477 unsigned Flags = 0; 1478 PrevInstLoc = DL; 1479 if (DL == PrologEndLoc) { 1480 Flags |= DWARF2_FLAG_PROLOGUE_END; 1481 PrologEndLoc = DebugLoc(); 1482 } 1483 if (PrologEndLoc.isUnknown()) 1484 Flags |= DWARF2_FLAG_IS_STMT; 1485 1486 if (!DL.isUnknown()) { 1487 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext()); 1488 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags); 1489 } else 1490 recordSourceLine(0, 0, 0, 0); 1491 } 1492 } 1493 1494 // Insert labels where requested. 1495 DenseMap<const MachineInstr*, MCSymbol*>::iterator I = 1496 LabelsBeforeInsn.find(MI); 1497 1498 // No label needed. 1499 if (I == LabelsBeforeInsn.end()) 1500 return; 1501 1502 // Label already assigned. 1503 if (I->second) 1504 return; 1505 1506 if (!PrevLabel) { 1507 PrevLabel = MMI->getContext().CreateTempSymbol(); 1508 Asm->OutStreamer.EmitLabel(PrevLabel); 1509 } 1510 I->second = PrevLabel; 1511} 1512 1513// Process end of an instruction. 1514void DwarfDebug::endInstruction(const MachineInstr *MI) { 1515 // Don't create a new label after DBG_VALUE instructions. 1516 // They don't generate code. 1517 if (!MI->isDebugValue()) 1518 PrevLabel = 0; 1519 1520 DenseMap<const MachineInstr*, MCSymbol*>::iterator I = 1521 LabelsAfterInsn.find(MI); 1522 1523 // No label needed. 1524 if (I == LabelsAfterInsn.end()) 1525 return; 1526 1527 // Label already assigned. 1528 if (I->second) 1529 return; 1530 1531 // We need a label after this instruction. 1532 if (!PrevLabel) { 1533 PrevLabel = MMI->getContext().CreateTempSymbol(); 1534 Asm->OutStreamer.EmitLabel(PrevLabel); 1535 } 1536 I->second = PrevLabel; 1537} 1538 1539// Each LexicalScope has first instruction and last instruction to mark 1540// beginning and end of a scope respectively. Create an inverse map that list 1541// scopes starts (and ends) with an instruction. One instruction may start (or 1542// end) multiple scopes. Ignore scopes that are not reachable. 1543void DwarfDebug::identifyScopeMarkers() { 1544 SmallVector<LexicalScope *, 4> WorkList; 1545 WorkList.push_back(LScopes.getCurrentFunctionScope()); 1546 while (!WorkList.empty()) { 1547 LexicalScope *S = WorkList.pop_back_val(); 1548 1549 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren(); 1550 if (!Children.empty()) 1551 for (SmallVectorImpl<LexicalScope *>::const_iterator SI = Children.begin(), 1552 SE = Children.end(); SI != SE; ++SI) 1553 WorkList.push_back(*SI); 1554 1555 if (S->isAbstractScope()) 1556 continue; 1557 1558 const SmallVectorImpl<InsnRange> &Ranges = S->getRanges(); 1559 if (Ranges.empty()) 1560 continue; 1561 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 1562 RE = Ranges.end(); RI != RE; ++RI) { 1563 assert(RI->first && "InsnRange does not have first instruction!"); 1564 assert(RI->second && "InsnRange does not have second instruction!"); 1565 requestLabelBeforeInsn(RI->first); 1566 requestLabelAfterInsn(RI->second); 1567 } 1568 } 1569} 1570 1571// Get MDNode for DebugLoc's scope. 1572static MDNode *getScopeNode(DebugLoc DL, const LLVMContext &Ctx) { 1573 if (MDNode *InlinedAt = DL.getInlinedAt(Ctx)) 1574 return getScopeNode(DebugLoc::getFromDILocation(InlinedAt), Ctx); 1575 return DL.getScope(Ctx); 1576} 1577 1578// Walk up the scope chain of given debug loc and find line number info 1579// for the function. 1580static DebugLoc getFnDebugLoc(DebugLoc DL, const LLVMContext &Ctx) { 1581 const MDNode *Scope = getScopeNode(DL, Ctx); 1582 DISubprogram SP = getDISubprogram(Scope); 1583 if (SP.isSubprogram()) { 1584 // Check for number of operands since the compatibility is 1585 // cheap here. 1586 if (SP->getNumOperands() > 19) 1587 return DebugLoc::get(SP.getScopeLineNumber(), 0, SP); 1588 else 1589 return DebugLoc::get(SP.getLineNumber(), 0, SP); 1590 } 1591 1592 return DebugLoc(); 1593} 1594 1595// Gather pre-function debug information. Assumes being called immediately 1596// after the function entry point has been emitted. 1597void DwarfDebug::beginFunction(const MachineFunction *MF) { 1598 1599 // If there's no debug info for the function we're not going to do anything. 1600 if (!MMI->hasDebugInfo()) 1601 return; 1602 1603 // Grab the lexical scopes for the function, if we don't have any of those 1604 // then we're not going to be able to do anything. 1605 LScopes.initialize(*MF); 1606 if (LScopes.empty()) 1607 return; 1608 1609 assert(UserVariables.empty() && DbgValues.empty() && "Maps weren't cleaned"); 1610 1611 // Make sure that each lexical scope will have a begin/end label. 1612 identifyScopeMarkers(); 1613 1614 // Set DwarfCompileUnitID in MCContext to the Compile Unit this function 1615 // belongs to so that we add to the correct per-cu line table in the 1616 // non-asm case. 1617 LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); 1618 CompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode()); 1619 assert(TheCU && "Unable to find compile unit!"); 1620 if (Asm->TM.hasMCUseLoc() && Asm->OutStreamer.hasRawTextSupport()) 1621 // Use a single line table if we are using .loc and generating assembly. 1622 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0); 1623 else 1624 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID()); 1625 1626 // Emit a label for the function so that we have a beginning address. 1627 FunctionBeginSym = Asm->GetTempSymbol("func_begin", Asm->getFunctionNumber()); 1628 // Assumes in correct section after the entry point. 1629 Asm->OutStreamer.EmitLabel(FunctionBeginSym); 1630 1631 const TargetRegisterInfo *TRI = Asm->TM.getRegisterInfo(); 1632 // LiveUserVar - Map physreg numbers to the MDNode they contain. 1633 std::vector<const MDNode *> LiveUserVar(TRI->getNumRegs()); 1634 1635 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end(); I != E; 1636 ++I) { 1637 bool AtBlockEntry = true; 1638 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end(); 1639 II != IE; ++II) { 1640 const MachineInstr *MI = II; 1641 1642 if (MI->isDebugValue()) { 1643 assert(MI->getNumOperands() > 1 && "Invalid machine instruction!"); 1644 1645 // Keep track of user variables. 1646 const MDNode *Var = 1647 MI->getOperand(MI->getNumOperands() - 1).getMetadata(); 1648 1649 // Variable is in a register, we need to check for clobbers. 1650 if (isDbgValueInDefinedReg(MI)) 1651 LiveUserVar[MI->getOperand(0).getReg()] = Var; 1652 1653 // Check the history of this variable. 1654 SmallVectorImpl<const MachineInstr *> &History = DbgValues[Var]; 1655 if (History.empty()) { 1656 UserVariables.push_back(Var); 1657 // The first mention of a function argument gets the FunctionBeginSym 1658 // label, so arguments are visible when breaking at function entry. 1659 DIVariable DV(Var); 1660 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable && 1661 DISubprogram(getDISubprogram(DV.getContext())) 1662 .describes(MF->getFunction())) 1663 LabelsBeforeInsn[MI] = FunctionBeginSym; 1664 } else { 1665 // We have seen this variable before. Try to coalesce DBG_VALUEs. 1666 const MachineInstr *Prev = History.back(); 1667 if (Prev->isDebugValue()) { 1668 // Coalesce identical entries at the end of History. 1669 if (History.size() >= 2 && 1670 Prev->isIdenticalTo(History[History.size() - 2])) { 1671 DEBUG(dbgs() << "Coalescing identical DBG_VALUE entries:\n" 1672 << "\t" << *Prev << "\t" 1673 << *History[History.size() - 2] << "\n"); 1674 History.pop_back(); 1675 } 1676 1677 // Terminate old register assignments that don't reach MI; 1678 MachineFunction::const_iterator PrevMBB = Prev->getParent(); 1679 if (PrevMBB != I && (!AtBlockEntry || llvm::next(PrevMBB) != I) && 1680 isDbgValueInDefinedReg(Prev)) { 1681 // Previous register assignment needs to terminate at the end of 1682 // its basic block. 1683 MachineBasicBlock::const_iterator LastMI = 1684 PrevMBB->getLastNonDebugInstr(); 1685 if (LastMI == PrevMBB->end()) { 1686 // Drop DBG_VALUE for empty range. 1687 DEBUG(dbgs() << "Dropping DBG_VALUE for empty range:\n" 1688 << "\t" << *Prev << "\n"); 1689 History.pop_back(); 1690 } else if (llvm::next(PrevMBB) != PrevMBB->getParent()->end()) 1691 // Terminate after LastMI. 1692 History.push_back(LastMI); 1693 } 1694 } 1695 } 1696 History.push_back(MI); 1697 } else { 1698 // Not a DBG_VALUE instruction. 1699 if (!MI->isLabel()) 1700 AtBlockEntry = false; 1701 1702 // First known non-DBG_VALUE and non-frame setup location marks 1703 // the beginning of the function body. 1704 if (!MI->getFlag(MachineInstr::FrameSetup) && 1705 (PrologEndLoc.isUnknown() && !MI->getDebugLoc().isUnknown())) 1706 PrologEndLoc = MI->getDebugLoc(); 1707 1708 // Check if the instruction clobbers any registers with debug vars. 1709 for (MachineInstr::const_mop_iterator MOI = MI->operands_begin(), 1710 MOE = MI->operands_end(); 1711 MOI != MOE; ++MOI) { 1712 if (!MOI->isReg() || !MOI->isDef() || !MOI->getReg()) 1713 continue; 1714 for (MCRegAliasIterator AI(MOI->getReg(), TRI, true); AI.isValid(); 1715 ++AI) { 1716 unsigned Reg = *AI; 1717 const MDNode *Var = LiveUserVar[Reg]; 1718 if (!Var) 1719 continue; 1720 // Reg is now clobbered. 1721 LiveUserVar[Reg] = 0; 1722 1723 // Was MD last defined by a DBG_VALUE referring to Reg? 1724 DbgValueHistoryMap::iterator HistI = DbgValues.find(Var); 1725 if (HistI == DbgValues.end()) 1726 continue; 1727 SmallVectorImpl<const MachineInstr *> &History = HistI->second; 1728 if (History.empty()) 1729 continue; 1730 const MachineInstr *Prev = History.back(); 1731 // Sanity-check: Register assignments are terminated at the end of 1732 // their block. 1733 if (!Prev->isDebugValue() || Prev->getParent() != MI->getParent()) 1734 continue; 1735 // Is the variable still in Reg? 1736 if (!isDbgValueInDefinedReg(Prev) || 1737 Prev->getOperand(0).getReg() != Reg) 1738 continue; 1739 // Var is clobbered. Make sure the next instruction gets a label. 1740 History.push_back(MI); 1741 } 1742 } 1743 } 1744 } 1745 } 1746 1747 for (DbgValueHistoryMap::iterator I = DbgValues.begin(), E = DbgValues.end(); 1748 I != E; ++I) { 1749 SmallVectorImpl<const MachineInstr *> &History = I->second; 1750 if (History.empty()) 1751 continue; 1752 1753 // Make sure the final register assignments are terminated. 1754 const MachineInstr *Prev = History.back(); 1755 if (Prev->isDebugValue() && isDbgValueInDefinedReg(Prev)) { 1756 const MachineBasicBlock *PrevMBB = Prev->getParent(); 1757 MachineBasicBlock::const_iterator LastMI = 1758 PrevMBB->getLastNonDebugInstr(); 1759 if (LastMI == PrevMBB->end()) 1760 // Drop DBG_VALUE for empty range. 1761 History.pop_back(); 1762 else if (PrevMBB != &PrevMBB->getParent()->back()) { 1763 // Terminate after LastMI. 1764 History.push_back(LastMI); 1765 } 1766 } 1767 // Request labels for the full history. 1768 for (unsigned i = 0, e = History.size(); i != e; ++i) { 1769 const MachineInstr *MI = History[i]; 1770 if (MI->isDebugValue()) 1771 requestLabelBeforeInsn(MI); 1772 else 1773 requestLabelAfterInsn(MI); 1774 } 1775 } 1776 1777 PrevInstLoc = DebugLoc(); 1778 PrevLabel = FunctionBeginSym; 1779 1780 // Record beginning of function. 1781 if (!PrologEndLoc.isUnknown()) { 1782 DebugLoc FnStartDL = 1783 getFnDebugLoc(PrologEndLoc, MF->getFunction()->getContext()); 1784 recordSourceLine( 1785 FnStartDL.getLine(), FnStartDL.getCol(), 1786 FnStartDL.getScope(MF->getFunction()->getContext()), 1787 // We'd like to list the prologue as "not statements" but GDB behaves 1788 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing. 1789 DWARF2_FLAG_IS_STMT); 1790 } 1791} 1792 1793void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) { 1794 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS]; 1795 DIVariable DV = Var->getVariable(); 1796 // Variables with positive arg numbers are parameters. 1797 if (unsigned ArgNum = DV.getArgNumber()) { 1798 // Keep all parameters in order at the start of the variable list to ensure 1799 // function types are correct (no out-of-order parameters) 1800 // 1801 // This could be improved by only doing it for optimized builds (unoptimized 1802 // builds have the right order to begin with), searching from the back (this 1803 // would catch the unoptimized case quickly), or doing a binary search 1804 // rather than linear search. 1805 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin(); 1806 while (I != Vars.end()) { 1807 unsigned CurNum = (*I)->getVariable().getArgNumber(); 1808 // A local (non-parameter) variable has been found, insert immediately 1809 // before it. 1810 if (CurNum == 0) 1811 break; 1812 // A later indexed parameter has been found, insert immediately before it. 1813 if (CurNum > ArgNum) 1814 break; 1815 ++I; 1816 } 1817 Vars.insert(I, Var); 1818 return; 1819 } 1820 1821 Vars.push_back(Var); 1822} 1823 1824// Gather and emit post-function debug information. 1825void DwarfDebug::endFunction(const MachineFunction *MF) { 1826 if (!MMI->hasDebugInfo() || LScopes.empty()) return; 1827 1828 // Define end label for subprogram. 1829 FunctionEndSym = Asm->GetTempSymbol("func_end", 1830 Asm->getFunctionNumber()); 1831 // Assumes in correct section after the entry point. 1832 Asm->OutStreamer.EmitLabel(FunctionEndSym); 1833 // Set DwarfCompileUnitID in MCContext to default value. 1834 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0); 1835 1836 SmallPtrSet<const MDNode *, 16> ProcessedVars; 1837 collectVariableInfo(MF, ProcessedVars); 1838 1839 LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); 1840 CompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode()); 1841 assert(TheCU && "Unable to find compile unit!"); 1842 1843 // Construct abstract scopes. 1844 ArrayRef<LexicalScope *> AList = LScopes.getAbstractScopesList(); 1845 for (unsigned i = 0, e = AList.size(); i != e; ++i) { 1846 LexicalScope *AScope = AList[i]; 1847 DISubprogram SP(AScope->getScopeNode()); 1848 if (SP.isSubprogram()) { 1849 // Collect info for variables that were optimized out. 1850 DIArray Variables = SP.getVariables(); 1851 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) { 1852 DIVariable DV(Variables.getElement(i)); 1853 if (!DV || !DV.isVariable() || !ProcessedVars.insert(DV)) 1854 continue; 1855 // Check that DbgVariable for DV wasn't created earlier, when 1856 // findAbstractVariable() was called for inlined instance of DV. 1857 LLVMContext &Ctx = DV->getContext(); 1858 DIVariable CleanDV = cleanseInlinedVariable(DV, Ctx); 1859 if (AbstractVariables.lookup(CleanDV)) 1860 continue; 1861 if (LexicalScope *Scope = LScopes.findAbstractScope(DV.getContext())) 1862 addScopeVariable(Scope, new DbgVariable(DV, NULL, this)); 1863 } 1864 } 1865 if (ProcessedSPNodes.count(AScope->getScopeNode()) == 0) 1866 constructScopeDIE(TheCU, AScope); 1867 } 1868 1869 DIE *CurFnDIE = constructScopeDIE(TheCU, FnScope); 1870 1871 if (!MF->getTarget().Options.DisableFramePointerElim(*MF)) 1872 TheCU->addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr); 1873 1874 // Clear debug info 1875 for (ScopeVariablesMap::iterator 1876 I = ScopeVariables.begin(), E = ScopeVariables.end(); I != E; ++I) 1877 DeleteContainerPointers(I->second); 1878 ScopeVariables.clear(); 1879 DeleteContainerPointers(CurrentFnArguments); 1880 UserVariables.clear(); 1881 DbgValues.clear(); 1882 AbstractVariables.clear(); 1883 LabelsBeforeInsn.clear(); 1884 LabelsAfterInsn.clear(); 1885 PrevLabel = NULL; 1886} 1887 1888// Register a source line with debug info. Returns the unique label that was 1889// emitted and which provides correspondence to the source line list. 1890void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S, 1891 unsigned Flags) { 1892 StringRef Fn; 1893 StringRef Dir; 1894 unsigned Src = 1; 1895 if (S) { 1896 DIDescriptor Scope(S); 1897 1898 if (Scope.isCompileUnit()) { 1899 DICompileUnit CU(S); 1900 Fn = CU.getFilename(); 1901 Dir = CU.getDirectory(); 1902 } else if (Scope.isFile()) { 1903 DIFile F(S); 1904 Fn = F.getFilename(); 1905 Dir = F.getDirectory(); 1906 } else if (Scope.isSubprogram()) { 1907 DISubprogram SP(S); 1908 Fn = SP.getFilename(); 1909 Dir = SP.getDirectory(); 1910 } else if (Scope.isLexicalBlockFile()) { 1911 DILexicalBlockFile DBF(S); 1912 Fn = DBF.getFilename(); 1913 Dir = DBF.getDirectory(); 1914 } else if (Scope.isLexicalBlock()) { 1915 DILexicalBlock DB(S); 1916 Fn = DB.getFilename(); 1917 Dir = DB.getDirectory(); 1918 } else 1919 llvm_unreachable("Unexpected scope info"); 1920 1921 Src = getOrCreateSourceID(Fn, Dir, 1922 Asm->OutStreamer.getContext().getDwarfCompileUnitID()); 1923 } 1924 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0, 0, Fn); 1925} 1926 1927//===----------------------------------------------------------------------===// 1928// Emit Methods 1929//===----------------------------------------------------------------------===// 1930 1931// Compute the size and offset of a DIE. The offset is relative to start of the 1932// CU. It returns the offset after laying out the DIE. 1933unsigned 1934DwarfUnits::computeSizeAndOffset(DIE *Die, unsigned Offset) { 1935 // Get the children. 1936 const std::vector<DIE *> &Children = Die->getChildren(); 1937 1938 // Record the abbreviation. 1939 assignAbbrevNumber(Die->getAbbrev()); 1940 1941 // Get the abbreviation for this DIE. 1942 unsigned AbbrevNumber = Die->getAbbrevNumber(); 1943 const DIEAbbrev *Abbrev = Abbreviations[AbbrevNumber - 1]; 1944 1945 // Set DIE offset 1946 Die->setOffset(Offset); 1947 1948 // Start the size with the size of abbreviation code. 1949 Offset += MCAsmInfo::getULEB128Size(AbbrevNumber); 1950 1951 const SmallVectorImpl<DIEValue*> &Values = Die->getValues(); 1952 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev->getData(); 1953 1954 // Size the DIE attribute values. 1955 for (unsigned i = 0, N = Values.size(); i < N; ++i) 1956 // Size attribute value. 1957 Offset += Values[i]->SizeOf(Asm, AbbrevData[i].getForm()); 1958 1959 // Size the DIE children if any. 1960 if (!Children.empty()) { 1961 assert(Abbrev->getChildrenFlag() == dwarf::DW_CHILDREN_yes && 1962 "Children flag not set"); 1963 1964 for (unsigned j = 0, M = Children.size(); j < M; ++j) 1965 Offset = computeSizeAndOffset(Children[j], Offset); 1966 1967 // End of children marker. 1968 Offset += sizeof(int8_t); 1969 } 1970 1971 Die->setSize(Offset - Die->getOffset()); 1972 return Offset; 1973} 1974 1975// Compute the size and offset for each DIE. 1976void DwarfUnits::computeSizeAndOffsets() { 1977 // Offset from the first CU in the debug info section is 0 initially. 1978 unsigned SecOffset = 0; 1979 1980 // Iterate over each compile unit and set the size and offsets for each 1981 // DIE within each compile unit. All offsets are CU relative. 1982 for (SmallVectorImpl<CompileUnit *>::iterator I = CUs.begin(), 1983 E = CUs.end(); I != E; ++I) { 1984 (*I)->setDebugInfoOffset(SecOffset); 1985 1986 // CU-relative offset is reset to 0 here. 1987 unsigned Offset = sizeof(int32_t) + // Length of Unit Info 1988 (*I)->getHeaderSize(); // Unit-specific headers 1989 1990 // EndOffset here is CU-relative, after laying out 1991 // all of the CU DIE. 1992 unsigned EndOffset = computeSizeAndOffset((*I)->getCUDie(), Offset); 1993 SecOffset += EndOffset; 1994 } 1995} 1996 1997// Emit initial Dwarf sections with a label at the start of each one. 1998void DwarfDebug::emitSectionLabels() { 1999 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); 2000 2001 // Dwarf sections base addresses. 2002 DwarfInfoSectionSym = 2003 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info"); 2004 DwarfAbbrevSectionSym = 2005 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev"); 2006 if (useSplitDwarf()) 2007 DwarfAbbrevDWOSectionSym = 2008 emitSectionSym(Asm, TLOF.getDwarfAbbrevDWOSection(), 2009 "section_abbrev_dwo"); 2010 emitSectionSym(Asm, TLOF.getDwarfARangesSection()); 2011 2012 if (const MCSection *MacroInfo = TLOF.getDwarfMacroInfoSection()) 2013 emitSectionSym(Asm, MacroInfo); 2014 2015 DwarfLineSectionSym = 2016 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line"); 2017 emitSectionSym(Asm, TLOF.getDwarfLocSection()); 2018 if (GenerateGnuPubSections) { 2019 DwarfGnuPubNamesSectionSym = 2020 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection()); 2021 DwarfGnuPubTypesSectionSym = 2022 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection()); 2023 } else if (HasDwarfPubSections) { 2024 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection()); 2025 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection()); 2026 } 2027 2028 DwarfStrSectionSym = 2029 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string"); 2030 if (useSplitDwarf()) { 2031 DwarfStrDWOSectionSym = 2032 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string"); 2033 DwarfAddrSectionSym = 2034 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec"); 2035 } 2036 DwarfDebugRangeSectionSym = emitSectionSym(Asm, TLOF.getDwarfRangesSection(), 2037 "debug_range"); 2038 2039 DwarfDebugLocSectionSym = emitSectionSym(Asm, TLOF.getDwarfLocSection(), 2040 "section_debug_loc"); 2041 2042 TextSectionSym = emitSectionSym(Asm, TLOF.getTextSection(), "text_begin"); 2043 emitSectionSym(Asm, TLOF.getDataSection()); 2044} 2045 2046// Recursively emits a debug information entry. 2047void DwarfDebug::emitDIE(DIE *Die, ArrayRef<DIEAbbrev *> Abbrevs) { 2048 // Get the abbreviation for this DIE. 2049 unsigned AbbrevNumber = Die->getAbbrevNumber(); 2050 const DIEAbbrev *Abbrev = Abbrevs[AbbrevNumber - 1]; 2051 2052 // Emit the code (index) for the abbreviation. 2053 if (Asm->isVerbose()) 2054 Asm->OutStreamer.AddComment("Abbrev [" + Twine(AbbrevNumber) + "] 0x" + 2055 Twine::utohexstr(Die->getOffset()) + ":0x" + 2056 Twine::utohexstr(Die->getSize()) + " " + 2057 dwarf::TagString(Abbrev->getTag())); 2058 Asm->EmitULEB128(AbbrevNumber); 2059 2060 const SmallVectorImpl<DIEValue*> &Values = Die->getValues(); 2061 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev->getData(); 2062 2063 // Emit the DIE attribute values. 2064 for (unsigned i = 0, N = Values.size(); i < N; ++i) { 2065 dwarf::Attribute Attr = AbbrevData[i].getAttribute(); 2066 dwarf::Form Form = AbbrevData[i].getForm(); 2067 assert(Form && "Too many attributes for DIE (check abbreviation)"); 2068 2069 if (Asm->isVerbose()) 2070 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr)); 2071 2072 switch (Attr) { 2073 case dwarf::DW_AT_abstract_origin: 2074 case dwarf::DW_AT_type: 2075 case dwarf::DW_AT_friend: 2076 case dwarf::DW_AT_specification: 2077 case dwarf::DW_AT_import: 2078 case dwarf::DW_AT_containing_type: { 2079 DIEEntry *E = cast<DIEEntry>(Values[i]); 2080 DIE *Origin = E->getEntry(); 2081 unsigned Addr = Origin->getOffset(); 2082 if (Form == dwarf::DW_FORM_ref_addr) { 2083 assert(!useSplitDwarf() && "TODO: dwo files can't have relocations."); 2084 // For DW_FORM_ref_addr, output the offset from beginning of debug info 2085 // section. Origin->getOffset() returns the offset from start of the 2086 // compile unit. 2087 CompileUnit *CU = CUDieMap.lookup(Origin->getCompileUnit()); 2088 assert(CU && "CUDie should belong to a CU."); 2089 Addr += CU->getDebugInfoOffset(); 2090 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2091 Asm->EmitLabelPlusOffset(DwarfInfoSectionSym, Addr, 2092 DIEEntry::getRefAddrSize(Asm)); 2093 else 2094 Asm->EmitLabelOffsetDifference(DwarfInfoSectionSym, Addr, 2095 DwarfInfoSectionSym, 2096 DIEEntry::getRefAddrSize(Asm)); 2097 } else { 2098 // Make sure Origin belong to the same CU. 2099 assert(Die->getCompileUnit() == Origin->getCompileUnit() && 2100 "The referenced DIE should belong to the same CU in ref4"); 2101 Asm->EmitInt32(Addr); 2102 } 2103 break; 2104 } 2105 case dwarf::DW_AT_ranges: { 2106 // DW_AT_range Value encodes offset in debug_range section. 2107 DIEInteger *V = cast<DIEInteger>(Values[i]); 2108 2109 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) { 2110 Asm->EmitLabelPlusOffset(DwarfDebugRangeSectionSym, 2111 V->getValue(), 2112 4); 2113 } else { 2114 Asm->EmitLabelOffsetDifference(DwarfDebugRangeSectionSym, 2115 V->getValue(), 2116 DwarfDebugRangeSectionSym, 2117 4); 2118 } 2119 break; 2120 } 2121 case dwarf::DW_AT_location: { 2122 if (DIELabel *L = dyn_cast<DIELabel>(Values[i])) { 2123 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2124 Asm->EmitLabelReference(L->getValue(), 4); 2125 else 2126 Asm->EmitLabelDifference(L->getValue(), DwarfDebugLocSectionSym, 4); 2127 } else { 2128 Values[i]->EmitValue(Asm, Form); 2129 } 2130 break; 2131 } 2132 case dwarf::DW_AT_accessibility: { 2133 if (Asm->isVerbose()) { 2134 DIEInteger *V = cast<DIEInteger>(Values[i]); 2135 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(V->getValue())); 2136 } 2137 Values[i]->EmitValue(Asm, Form); 2138 break; 2139 } 2140 default: 2141 // Emit an attribute using the defined form. 2142 Values[i]->EmitValue(Asm, Form); 2143 break; 2144 } 2145 } 2146 2147 // Emit the DIE children if any. 2148 if (Abbrev->getChildrenFlag() == dwarf::DW_CHILDREN_yes) { 2149 const std::vector<DIE *> &Children = Die->getChildren(); 2150 2151 for (unsigned j = 0, M = Children.size(); j < M; ++j) 2152 emitDIE(Children[j], Abbrevs); 2153 2154 if (Asm->isVerbose()) 2155 Asm->OutStreamer.AddComment("End Of Children Mark"); 2156 Asm->EmitInt8(0); 2157 } 2158} 2159 2160// Emit the various dwarf units to the unit section USection with 2161// the abbreviations going into ASection. 2162void DwarfUnits::emitUnits(DwarfDebug *DD, 2163 const MCSection *USection, 2164 const MCSection *ASection, 2165 const MCSymbol *ASectionSym) { 2166 Asm->OutStreamer.SwitchSection(USection); 2167 for (SmallVectorImpl<CompileUnit *>::iterator I = CUs.begin(), 2168 E = CUs.end(); I != E; ++I) { 2169 CompileUnit *TheCU = *I; 2170 DIE *Die = TheCU->getCUDie(); 2171 2172 // Emit the compile units header. 2173 Asm->OutStreamer 2174 .EmitLabel(Asm->GetTempSymbol(USection->getLabelBeginName(), 2175 TheCU->getUniqueID())); 2176 2177 // Emit size of content not including length itself 2178 Asm->OutStreamer.AddComment("Length of Unit"); 2179 Asm->EmitInt32(TheCU->getHeaderSize() + Die->getSize()); 2180 2181 TheCU->emitHeader(ASection, ASectionSym); 2182 2183 DD->emitDIE(Die, Abbreviations); 2184 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol(USection->getLabelEndName(), 2185 TheCU->getUniqueID())); 2186 } 2187} 2188 2189// Emit the debug info section. 2190void DwarfDebug::emitDebugInfo() { 2191 DwarfUnits &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; 2192 2193 Holder.emitUnits(this, Asm->getObjFileLowering().getDwarfInfoSection(), 2194 Asm->getObjFileLowering().getDwarfAbbrevSection(), 2195 DwarfAbbrevSectionSym); 2196} 2197 2198// Emit the abbreviation section. 2199void DwarfDebug::emitAbbreviations() { 2200 if (!useSplitDwarf()) 2201 emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection(), 2202 &Abbreviations); 2203 else 2204 emitSkeletonAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection()); 2205} 2206 2207void DwarfDebug::emitAbbrevs(const MCSection *Section, 2208 std::vector<DIEAbbrev *> *Abbrevs) { 2209 // Check to see if it is worth the effort. 2210 if (!Abbrevs->empty()) { 2211 // Start the debug abbrev section. 2212 Asm->OutStreamer.SwitchSection(Section); 2213 2214 MCSymbol *Begin = Asm->GetTempSymbol(Section->getLabelBeginName()); 2215 Asm->OutStreamer.EmitLabel(Begin); 2216 2217 // For each abbrevation. 2218 for (unsigned i = 0, N = Abbrevs->size(); i < N; ++i) { 2219 // Get abbreviation data 2220 const DIEAbbrev *Abbrev = Abbrevs->at(i); 2221 2222 // Emit the abbrevations code (base 1 index.) 2223 Asm->EmitULEB128(Abbrev->getNumber(), "Abbreviation Code"); 2224 2225 // Emit the abbreviations data. 2226 Abbrev->Emit(Asm); 2227 } 2228 2229 // Mark end of abbreviations. 2230 Asm->EmitULEB128(0, "EOM(3)"); 2231 2232 MCSymbol *End = Asm->GetTempSymbol(Section->getLabelEndName()); 2233 Asm->OutStreamer.EmitLabel(End); 2234 } 2235} 2236 2237// Emit the last address of the section and the end of the line matrix. 2238void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) { 2239 // Define last address of section. 2240 Asm->OutStreamer.AddComment("Extended Op"); 2241 Asm->EmitInt8(0); 2242 2243 Asm->OutStreamer.AddComment("Op size"); 2244 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1); 2245 Asm->OutStreamer.AddComment("DW_LNE_set_address"); 2246 Asm->EmitInt8(dwarf::DW_LNE_set_address); 2247 2248 Asm->OutStreamer.AddComment("Section end label"); 2249 2250 Asm->OutStreamer.EmitSymbolValue(Asm->GetTempSymbol("section_end",SectionEnd), 2251 Asm->getDataLayout().getPointerSize()); 2252 2253 // Mark end of matrix. 2254 Asm->OutStreamer.AddComment("DW_LNE_end_sequence"); 2255 Asm->EmitInt8(0); 2256 Asm->EmitInt8(1); 2257 Asm->EmitInt8(1); 2258} 2259 2260// Emit visible names into a hashed accelerator table section. 2261void DwarfDebug::emitAccelNames() { 2262 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2263 dwarf::DW_FORM_data4)); 2264 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2265 E = CUMap.end(); I != E; ++I) { 2266 CompileUnit *TheCU = I->second; 2267 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelNames(); 2268 for (StringMap<std::vector<DIE*> >::const_iterator 2269 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2270 StringRef Name = GI->getKey(); 2271 const std::vector<DIE *> &Entities = GI->second; 2272 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2273 DE = Entities.end(); DI != DE; ++DI) 2274 AT.AddName(Name, (*DI)); 2275 } 2276 } 2277 2278 AT.FinalizeTable(Asm, "Names"); 2279 Asm->OutStreamer.SwitchSection( 2280 Asm->getObjFileLowering().getDwarfAccelNamesSection()); 2281 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin"); 2282 Asm->OutStreamer.EmitLabel(SectionBegin); 2283 2284 // Emit the full data. 2285 AT.Emit(Asm, SectionBegin, &InfoHolder); 2286} 2287 2288// Emit objective C classes and categories into a hashed accelerator table 2289// section. 2290void DwarfDebug::emitAccelObjC() { 2291 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2292 dwarf::DW_FORM_data4)); 2293 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2294 E = CUMap.end(); I != E; ++I) { 2295 CompileUnit *TheCU = I->second; 2296 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelObjC(); 2297 for (StringMap<std::vector<DIE*> >::const_iterator 2298 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2299 StringRef Name = GI->getKey(); 2300 const std::vector<DIE *> &Entities = GI->second; 2301 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2302 DE = Entities.end(); DI != DE; ++DI) 2303 AT.AddName(Name, (*DI)); 2304 } 2305 } 2306 2307 AT.FinalizeTable(Asm, "ObjC"); 2308 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2309 .getDwarfAccelObjCSection()); 2310 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin"); 2311 Asm->OutStreamer.EmitLabel(SectionBegin); 2312 2313 // Emit the full data. 2314 AT.Emit(Asm, SectionBegin, &InfoHolder); 2315} 2316 2317// Emit namespace dies into a hashed accelerator table. 2318void DwarfDebug::emitAccelNamespaces() { 2319 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2320 dwarf::DW_FORM_data4)); 2321 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2322 E = CUMap.end(); I != E; ++I) { 2323 CompileUnit *TheCU = I->second; 2324 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelNamespace(); 2325 for (StringMap<std::vector<DIE*> >::const_iterator 2326 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2327 StringRef Name = GI->getKey(); 2328 const std::vector<DIE *> &Entities = GI->second; 2329 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2330 DE = Entities.end(); DI != DE; ++DI) 2331 AT.AddName(Name, (*DI)); 2332 } 2333 } 2334 2335 AT.FinalizeTable(Asm, "namespac"); 2336 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2337 .getDwarfAccelNamespaceSection()); 2338 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin"); 2339 Asm->OutStreamer.EmitLabel(SectionBegin); 2340 2341 // Emit the full data. 2342 AT.Emit(Asm, SectionBegin, &InfoHolder); 2343} 2344 2345// Emit type dies into a hashed accelerator table. 2346void DwarfDebug::emitAccelTypes() { 2347 std::vector<DwarfAccelTable::Atom> Atoms; 2348 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2349 dwarf::DW_FORM_data4)); 2350 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, 2351 dwarf::DW_FORM_data2)); 2352 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, 2353 dwarf::DW_FORM_data1)); 2354 DwarfAccelTable AT(Atoms); 2355 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2356 E = CUMap.end(); I != E; ++I) { 2357 CompileUnit *TheCU = I->second; 2358 const StringMap<std::vector<std::pair<DIE*, unsigned > > > &Names 2359 = TheCU->getAccelTypes(); 2360 for (StringMap<std::vector<std::pair<DIE*, unsigned> > >::const_iterator 2361 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2362 StringRef Name = GI->getKey(); 2363 const std::vector<std::pair<DIE *, unsigned> > &Entities = GI->second; 2364 for (std::vector<std::pair<DIE *, unsigned> >::const_iterator DI 2365 = Entities.begin(), DE = Entities.end(); DI !=DE; ++DI) 2366 AT.AddName(Name, (*DI).first, (*DI).second); 2367 } 2368 } 2369 2370 AT.FinalizeTable(Asm, "types"); 2371 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2372 .getDwarfAccelTypesSection()); 2373 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin"); 2374 Asm->OutStreamer.EmitLabel(SectionBegin); 2375 2376 // Emit the full data. 2377 AT.Emit(Asm, SectionBegin, &InfoHolder); 2378} 2379 2380// Public name handling. 2381// The format for the various pubnames: 2382// 2383// dwarf pubnames - offset/name pairs where the offset is the offset into the CU 2384// for the DIE that is named. 2385// 2386// gnu pubnames - offset/index value/name tuples where the offset is the offset 2387// into the CU and the index value is computed according to the type of value 2388// for the DIE that is named. 2389// 2390// For type units the offset is the offset of the skeleton DIE. For split dwarf 2391// it's the offset within the debug_info/debug_types dwo section, however, the 2392// reference in the pubname header doesn't change. 2393 2394/// computeIndexValue - Compute the gdb index value for the DIE and CU. 2395static dwarf::PubIndexEntryDescriptor computeIndexValue(CompileUnit *CU, 2396 DIE *Die) { 2397 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC; 2398 2399 // We could have a specification DIE that has our most of our knowledge, 2400 // look for that now. 2401 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification); 2402 if (SpecVal) { 2403 DIE *SpecDIE = cast<DIEEntry>(SpecVal)->getEntry(); 2404 if (SpecDIE->findAttribute(dwarf::DW_AT_external)) 2405 Linkage = dwarf::GIEL_EXTERNAL; 2406 } else if (Die->findAttribute(dwarf::DW_AT_external)) 2407 Linkage = dwarf::GIEL_EXTERNAL; 2408 2409 switch (Die->getTag()) { 2410 case dwarf::DW_TAG_class_type: 2411 case dwarf::DW_TAG_structure_type: 2412 case dwarf::DW_TAG_union_type: 2413 case dwarf::DW_TAG_enumeration_type: 2414 return dwarf::PubIndexEntryDescriptor( 2415 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus 2416 ? dwarf::GIEL_STATIC 2417 : dwarf::GIEL_EXTERNAL); 2418 case dwarf::DW_TAG_typedef: 2419 case dwarf::DW_TAG_base_type: 2420 case dwarf::DW_TAG_subrange_type: 2421 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC); 2422 case dwarf::DW_TAG_namespace: 2423 return dwarf::GIEK_TYPE; 2424 case dwarf::DW_TAG_subprogram: 2425 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage); 2426 case dwarf::DW_TAG_constant: 2427 case dwarf::DW_TAG_variable: 2428 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage); 2429 case dwarf::DW_TAG_enumerator: 2430 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, 2431 dwarf::GIEL_STATIC); 2432 default: 2433 return dwarf::GIEK_NONE; 2434 } 2435} 2436 2437/// emitDebugPubNames - Emit visible names into a debug pubnames section. 2438/// 2439void DwarfDebug::emitDebugPubNames(bool GnuStyle) { 2440 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2441 const MCSection *PSec = 2442 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection() 2443 : Asm->getObjFileLowering().getDwarfPubNamesSection(); 2444 2445 typedef DenseMap<const MDNode*, CompileUnit*> CUMapType; 2446 for (CUMapType::iterator I = CUMap.begin(), E = CUMap.end(); I != E; ++I) { 2447 CompileUnit *TheCU = I->second; 2448 unsigned ID = TheCU->getUniqueID(); 2449 2450 // Start the dwarf pubnames section. 2451 Asm->OutStreamer.SwitchSection(PSec); 2452 2453 // Emit a label so we can reference the beginning of this pubname section. 2454 if (GnuStyle) 2455 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("gnu_pubnames", 2456 TheCU->getUniqueID())); 2457 2458 // Emit the header. 2459 Asm->OutStreamer.AddComment("Length of Public Names Info"); 2460 Asm->EmitLabelDifference(Asm->GetTempSymbol("pubnames_end", ID), 2461 Asm->GetTempSymbol("pubnames_begin", ID), 4); 2462 2463 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("pubnames_begin", ID)); 2464 2465 Asm->OutStreamer.AddComment("DWARF Version"); 2466 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION); 2467 2468 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info"); 2469 Asm->EmitSectionOffset(Asm->GetTempSymbol(ISec->getLabelBeginName(), ID), 2470 DwarfInfoSectionSym); 2471 2472 Asm->OutStreamer.AddComment("Compilation Unit Length"); 2473 Asm->EmitLabelDifference(Asm->GetTempSymbol(ISec->getLabelEndName(), ID), 2474 Asm->GetTempSymbol(ISec->getLabelBeginName(), ID), 2475 4); 2476 2477 // Emit the pubnames for this compilation unit. 2478 const StringMap<DIE*> &Globals = TheCU->getGlobalNames(); 2479 for (StringMap<DIE*>::const_iterator 2480 GI = Globals.begin(), GE = Globals.end(); GI != GE; ++GI) { 2481 const char *Name = GI->getKeyData(); 2482 DIE *Entity = GI->second; 2483 2484 Asm->OutStreamer.AddComment("DIE offset"); 2485 Asm->EmitInt32(Entity->getOffset()); 2486 2487 if (GnuStyle) { 2488 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheCU, Entity); 2489 Asm->OutStreamer.AddComment( 2490 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " + 2491 dwarf::GDBIndexEntryLinkageString(Desc.Linkage)); 2492 Asm->EmitInt8(Desc.toBits()); 2493 } 2494 2495 if (Asm->isVerbose()) 2496 Asm->OutStreamer.AddComment("External Name"); 2497 Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength()+1)); 2498 } 2499 2500 Asm->OutStreamer.AddComment("End Mark"); 2501 Asm->EmitInt32(0); 2502 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("pubnames_end", ID)); 2503 } 2504} 2505 2506void DwarfDebug::emitDebugPubTypes(bool GnuStyle) { 2507 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2508 const MCSection *PSec = 2509 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection() 2510 : Asm->getObjFileLowering().getDwarfPubTypesSection(); 2511 2512 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2513 E = CUMap.end(); 2514 I != E; ++I) { 2515 CompileUnit *TheCU = I->second; 2516 // Start the dwarf pubtypes section. 2517 Asm->OutStreamer.SwitchSection(PSec); 2518 2519 // Emit a label so we can reference the beginning of this pubtype section. 2520 if (GnuStyle) 2521 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("gnu_pubtypes", 2522 TheCU->getUniqueID())); 2523 2524 // Emit the header. 2525 Asm->OutStreamer.AddComment("Length of Public Types Info"); 2526 Asm->EmitLabelDifference( 2527 Asm->GetTempSymbol("pubtypes_end", TheCU->getUniqueID()), 2528 Asm->GetTempSymbol("pubtypes_begin", TheCU->getUniqueID()), 4); 2529 2530 Asm->OutStreamer.EmitLabel( 2531 Asm->GetTempSymbol("pubtypes_begin", TheCU->getUniqueID())); 2532 2533 if (Asm->isVerbose()) 2534 Asm->OutStreamer.AddComment("DWARF Version"); 2535 Asm->EmitInt16(dwarf::DW_PUBTYPES_VERSION); 2536 2537 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info"); 2538 Asm->EmitSectionOffset( 2539 Asm->GetTempSymbol(ISec->getLabelBeginName(), TheCU->getUniqueID()), 2540 DwarfInfoSectionSym); 2541 2542 Asm->OutStreamer.AddComment("Compilation Unit Length"); 2543 Asm->EmitLabelDifference( 2544 Asm->GetTempSymbol(ISec->getLabelEndName(), TheCU->getUniqueID()), 2545 Asm->GetTempSymbol(ISec->getLabelBeginName(), TheCU->getUniqueID()), 4); 2546 2547 // Emit the pubtypes. 2548 const StringMap<DIE *> &Globals = TheCU->getGlobalTypes(); 2549 for (StringMap<DIE *>::const_iterator GI = Globals.begin(), 2550 GE = Globals.end(); 2551 GI != GE; ++GI) { 2552 const char *Name = GI->getKeyData(); 2553 DIE *Entity = GI->second; 2554 2555 if (Asm->isVerbose()) 2556 Asm->OutStreamer.AddComment("DIE offset"); 2557 Asm->EmitInt32(Entity->getOffset()); 2558 2559 if (GnuStyle) { 2560 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheCU, Entity); 2561 Asm->OutStreamer.AddComment( 2562 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " + 2563 dwarf::GDBIndexEntryLinkageString(Desc.Linkage)); 2564 Asm->EmitInt8(Desc.toBits()); 2565 } 2566 2567 if (Asm->isVerbose()) 2568 Asm->OutStreamer.AddComment("External Name"); 2569 2570 // Emit the name with a terminating null byte. 2571 Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength() + 1)); 2572 } 2573 2574 Asm->OutStreamer.AddComment("End Mark"); 2575 Asm->EmitInt32(0); 2576 Asm->OutStreamer.EmitLabel( 2577 Asm->GetTempSymbol("pubtypes_end", TheCU->getUniqueID())); 2578 } 2579} 2580 2581// Emit strings into a string section. 2582void DwarfUnits::emitStrings(const MCSection *StrSection, 2583 const MCSection *OffsetSection = NULL, 2584 const MCSymbol *StrSecSym = NULL) { 2585 2586 if (StringPool.empty()) return; 2587 2588 // Start the dwarf str section. 2589 Asm->OutStreamer.SwitchSection(StrSection); 2590 2591 // Get all of the string pool entries and put them in an array by their ID so 2592 // we can sort them. 2593 SmallVector<std::pair<unsigned, 2594 StringMapEntry<std::pair<MCSymbol*, unsigned> >*>, 64> Entries; 2595 2596 for (StringMap<std::pair<MCSymbol*, unsigned> >::iterator 2597 I = StringPool.begin(), E = StringPool.end(); 2598 I != E; ++I) 2599 Entries.push_back(std::make_pair(I->second.second, &*I)); 2600 2601 array_pod_sort(Entries.begin(), Entries.end()); 2602 2603 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2604 // Emit a label for reference from debug information entries. 2605 Asm->OutStreamer.EmitLabel(Entries[i].second->getValue().first); 2606 2607 // Emit the string itself with a terminating null byte. 2608 Asm->OutStreamer.EmitBytes(StringRef(Entries[i].second->getKeyData(), 2609 Entries[i].second->getKeyLength()+1)); 2610 } 2611 2612 // If we've got an offset section go ahead and emit that now as well. 2613 if (OffsetSection) { 2614 Asm->OutStreamer.SwitchSection(OffsetSection); 2615 unsigned offset = 0; 2616 unsigned size = 4; // FIXME: DWARF64 is 8. 2617 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2618 Asm->OutStreamer.EmitIntValue(offset, size); 2619 offset += Entries[i].second->getKeyLength() + 1; 2620 } 2621 } 2622} 2623 2624// Emit strings into a string section. 2625void DwarfUnits::emitAddresses(const MCSection *AddrSection) { 2626 2627 if (AddressPool.empty()) return; 2628 2629 // Start the dwarf addr section. 2630 Asm->OutStreamer.SwitchSection(AddrSection); 2631 2632 // Order the address pool entries by ID 2633 SmallVector<const MCExpr *, 64> Entries(AddressPool.size()); 2634 2635 for (DenseMap<const MCExpr *, unsigned>::iterator I = AddressPool.begin(), 2636 E = AddressPool.end(); 2637 I != E; ++I) 2638 Entries[I->second] = I->first; 2639 2640 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2641 // Emit an expression for reference from debug information entries. 2642 if (const MCExpr *Expr = Entries[i]) 2643 Asm->OutStreamer.EmitValue(Expr, Asm->getDataLayout().getPointerSize()); 2644 else 2645 Asm->OutStreamer.EmitIntValue(0, Asm->getDataLayout().getPointerSize()); 2646 } 2647 2648} 2649 2650// Emit visible names into a debug str section. 2651void DwarfDebug::emitDebugStr() { 2652 DwarfUnits &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; 2653 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection()); 2654} 2655 2656// Emit locations into the debug loc section. 2657void DwarfDebug::emitDebugLoc() { 2658 if (DotDebugLocEntries.empty()) 2659 return; 2660 2661 for (SmallVectorImpl<DotDebugLocEntry>::iterator 2662 I = DotDebugLocEntries.begin(), E = DotDebugLocEntries.end(); 2663 I != E; ++I) { 2664 DotDebugLocEntry &Entry = *I; 2665 if (I + 1 != DotDebugLocEntries.end()) 2666 Entry.Merge(I+1); 2667 } 2668 2669 // Start the dwarf loc section. 2670 Asm->OutStreamer.SwitchSection( 2671 Asm->getObjFileLowering().getDwarfLocSection()); 2672 unsigned char Size = Asm->getDataLayout().getPointerSize(); 2673 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", 0)); 2674 unsigned index = 1; 2675 for (SmallVectorImpl<DotDebugLocEntry>::iterator 2676 I = DotDebugLocEntries.begin(), E = DotDebugLocEntries.end(); 2677 I != E; ++I, ++index) { 2678 DotDebugLocEntry &Entry = *I; 2679 if (Entry.isMerged()) continue; 2680 if (Entry.isEmpty()) { 2681 Asm->OutStreamer.EmitIntValue(0, Size); 2682 Asm->OutStreamer.EmitIntValue(0, Size); 2683 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", index)); 2684 } else { 2685 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size); 2686 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size); 2687 DIVariable DV(Entry.getVariable()); 2688 Asm->OutStreamer.AddComment("Loc expr size"); 2689 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol(); 2690 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol(); 2691 Asm->EmitLabelDifference(end, begin, 2); 2692 Asm->OutStreamer.EmitLabel(begin); 2693 if (Entry.isInt()) { 2694 DIBasicType BTy(DV.getType()); 2695 if (BTy.Verify() && 2696 (BTy.getEncoding() == dwarf::DW_ATE_signed 2697 || BTy.getEncoding() == dwarf::DW_ATE_signed_char)) { 2698 Asm->OutStreamer.AddComment("DW_OP_consts"); 2699 Asm->EmitInt8(dwarf::DW_OP_consts); 2700 Asm->EmitSLEB128(Entry.getInt()); 2701 } else { 2702 Asm->OutStreamer.AddComment("DW_OP_constu"); 2703 Asm->EmitInt8(dwarf::DW_OP_constu); 2704 Asm->EmitULEB128(Entry.getInt()); 2705 } 2706 } else if (Entry.isLocation()) { 2707 MachineLocation Loc = Entry.getLoc(); 2708 if (!DV.hasComplexAddress()) 2709 // Regular entry. 2710 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2711 else { 2712 // Complex address entry. 2713 unsigned N = DV.getNumAddrElements(); 2714 unsigned i = 0; 2715 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) { 2716 if (Loc.getOffset()) { 2717 i = 2; 2718 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2719 Asm->OutStreamer.AddComment("DW_OP_deref"); 2720 Asm->EmitInt8(dwarf::DW_OP_deref); 2721 Asm->OutStreamer.AddComment("DW_OP_plus_uconst"); 2722 Asm->EmitInt8(dwarf::DW_OP_plus_uconst); 2723 Asm->EmitSLEB128(DV.getAddrElement(1)); 2724 } else { 2725 // If first address element is OpPlus then emit 2726 // DW_OP_breg + Offset instead of DW_OP_reg + Offset. 2727 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1)); 2728 Asm->EmitDwarfRegOp(TLoc, DV.isIndirect()); 2729 i = 2; 2730 } 2731 } else { 2732 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2733 } 2734 2735 // Emit remaining complex address elements. 2736 for (; i < N; ++i) { 2737 uint64_t Element = DV.getAddrElement(i); 2738 if (Element == DIBuilder::OpPlus) { 2739 Asm->EmitInt8(dwarf::DW_OP_plus_uconst); 2740 Asm->EmitULEB128(DV.getAddrElement(++i)); 2741 } else if (Element == DIBuilder::OpDeref) { 2742 if (!Loc.isReg()) 2743 Asm->EmitInt8(dwarf::DW_OP_deref); 2744 } else 2745 llvm_unreachable("unknown Opcode found in complex address"); 2746 } 2747 } 2748 } 2749 // else ... ignore constant fp. There is not any good way to 2750 // to represent them here in dwarf. 2751 Asm->OutStreamer.EmitLabel(end); 2752 } 2753 } 2754} 2755 2756struct SymbolCUSorter { 2757 SymbolCUSorter(const MCStreamer &s) : Streamer(s) {} 2758 const MCStreamer &Streamer; 2759 2760 bool operator() (const SymbolCU &A, const SymbolCU &B) { 2761 unsigned IA = A.Sym ? Streamer.GetSymbolOrder(A.Sym) : 0; 2762 unsigned IB = B.Sym ? Streamer.GetSymbolOrder(B.Sym) : 0; 2763 2764 // Symbols with no order assigned should be placed at the end. 2765 // (e.g. section end labels) 2766 if (IA == 0) 2767 IA = (unsigned)(-1); 2768 if (IB == 0) 2769 IB = (unsigned)(-1); 2770 return IA < IB; 2771 } 2772}; 2773 2774static bool CUSort(const CompileUnit *A, const CompileUnit *B) { 2775 return (A->getUniqueID() < B->getUniqueID()); 2776} 2777 2778struct ArangeSpan { 2779 const MCSymbol *Start, *End; 2780}; 2781 2782// Emit a debug aranges section, containing a CU lookup for any 2783// address we can tie back to a CU. 2784void DwarfDebug::emitDebugARanges() { 2785 // Start the dwarf aranges section. 2786 Asm->OutStreamer 2787 .SwitchSection(Asm->getObjFileLowering().getDwarfARangesSection()); 2788 2789 typedef DenseMap<CompileUnit *, std::vector<ArangeSpan> > SpansType; 2790 2791 SpansType Spans; 2792 2793 // Build a list of sections used. 2794 std::vector<const MCSection *> Sections; 2795 for (SectionMapType::iterator it = SectionMap.begin(); it != SectionMap.end(); 2796 it++) { 2797 const MCSection *Section = it->first; 2798 Sections.push_back(Section); 2799 } 2800 2801 // Sort the sections into order. 2802 // This is only done to ensure consistent output order across different runs. 2803 std::sort(Sections.begin(), Sections.end(), SectionSort); 2804 2805 // Build a set of address spans, sorted by CU. 2806 for (size_t SecIdx=0;SecIdx<Sections.size();SecIdx++) { 2807 const MCSection *Section = Sections[SecIdx]; 2808 SmallVector<SymbolCU, 8> &List = SectionMap[Section]; 2809 if (List.size() < 2) 2810 continue; 2811 2812 // Sort the symbols by offset within the section. 2813 SymbolCUSorter sorter(Asm->OutStreamer); 2814 std::sort(List.begin(), List.end(), sorter); 2815 2816 // If we have no section (e.g. common), just write out 2817 // individual spans for each symbol. 2818 if (Section == NULL) { 2819 for (size_t n = 0; n < List.size(); n++) { 2820 const SymbolCU &Cur = List[n]; 2821 2822 ArangeSpan Span; 2823 Span.Start = Cur.Sym; 2824 Span.End = NULL; 2825 if (Cur.CU) 2826 Spans[Cur.CU].push_back(Span); 2827 } 2828 } else { 2829 // Build spans between each label. 2830 const MCSymbol *StartSym = List[0].Sym; 2831 for (size_t n = 1; n < List.size(); n++) { 2832 const SymbolCU &Prev = List[n - 1]; 2833 const SymbolCU &Cur = List[n]; 2834 2835 // Try and build the longest span we can within the same CU. 2836 if (Cur.CU != Prev.CU) { 2837 ArangeSpan Span; 2838 Span.Start = StartSym; 2839 Span.End = Cur.Sym; 2840 Spans[Prev.CU].push_back(Span); 2841 StartSym = Cur.Sym; 2842 } 2843 } 2844 } 2845 } 2846 2847 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2848 unsigned PtrSize = Asm->getDataLayout().getPointerSize(); 2849 2850 // Build a list of CUs used. 2851 std::vector<CompileUnit *> CUs; 2852 for (SpansType::iterator it = Spans.begin(); it != Spans.end(); it++) { 2853 CompileUnit *CU = it->first; 2854 CUs.push_back(CU); 2855 } 2856 2857 // Sort the CU list (again, to ensure consistent output order). 2858 std::sort(CUs.begin(), CUs.end(), CUSort); 2859 2860 // Emit an arange table for each CU we used. 2861 for (size_t CUIdx=0;CUIdx<CUs.size();CUIdx++) { 2862 CompileUnit *CU = CUs[CUIdx]; 2863 std::vector<ArangeSpan> &List = Spans[CU]; 2864 2865 // Emit size of content not including length itself. 2866 unsigned ContentSize 2867 = sizeof(int16_t) // DWARF ARange version number 2868 + sizeof(int32_t) // Offset of CU in the .debug_info section 2869 + sizeof(int8_t) // Pointer Size (in bytes) 2870 + sizeof(int8_t); // Segment Size (in bytes) 2871 2872 unsigned TupleSize = PtrSize * 2; 2873 2874 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple. 2875 unsigned Padding = 0; 2876 while (((sizeof(int32_t) + ContentSize + Padding) % TupleSize) != 0) 2877 Padding++; 2878 2879 ContentSize += Padding; 2880 ContentSize += (List.size() + 1) * TupleSize; 2881 2882 // For each compile unit, write the list of spans it covers. 2883 Asm->OutStreamer.AddComment("Length of ARange Set"); 2884 Asm->EmitInt32(ContentSize); 2885 Asm->OutStreamer.AddComment("DWARF Arange version number"); 2886 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION); 2887 Asm->OutStreamer.AddComment("Offset Into Debug Info Section"); 2888 Asm->EmitSectionOffset( 2889 Asm->GetTempSymbol(ISec->getLabelBeginName(), CU->getUniqueID()), 2890 DwarfInfoSectionSym); 2891 Asm->OutStreamer.AddComment("Address Size (in bytes)"); 2892 Asm->EmitInt8(PtrSize); 2893 Asm->OutStreamer.AddComment("Segment Size (in bytes)"); 2894 Asm->EmitInt8(0); 2895 2896 for (unsigned n = 0; n < Padding; n++) 2897 Asm->EmitInt8(0xff); 2898 2899 for (unsigned n = 0; n < List.size(); n++) { 2900 const ArangeSpan &Span = List[n]; 2901 Asm->EmitLabelReference(Span.Start, PtrSize); 2902 2903 // Calculate the size as being from the span start to it's end. 2904 if (Span.End) { 2905 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize); 2906 } else { 2907 // For symbols without an end marker (e.g. common), we 2908 // write a single arange entry containing just that one symbol. 2909 uint64_t Size = SymSize[Span.Start]; 2910 if (Size == 0) 2911 Size = 1; 2912 2913 Asm->OutStreamer.EmitIntValue(Size, PtrSize); 2914 } 2915 } 2916 2917 Asm->OutStreamer.AddComment("ARange terminator"); 2918 Asm->OutStreamer.EmitIntValue(0, PtrSize); 2919 Asm->OutStreamer.EmitIntValue(0, PtrSize); 2920 } 2921} 2922 2923// Emit visible names into a debug ranges section. 2924void DwarfDebug::emitDebugRanges() { 2925 // Start the dwarf ranges section. 2926 Asm->OutStreamer 2927 .SwitchSection(Asm->getObjFileLowering().getDwarfRangesSection()); 2928 unsigned char Size = Asm->getDataLayout().getPointerSize(); 2929 for (SmallVectorImpl<const MCSymbol *>::iterator 2930 I = DebugRangeSymbols.begin(), E = DebugRangeSymbols.end(); 2931 I != E; ++I) { 2932 if (*I) 2933 Asm->OutStreamer.EmitSymbolValue(const_cast<MCSymbol*>(*I), Size); 2934 else 2935 Asm->OutStreamer.EmitIntValue(0, Size); 2936 } 2937} 2938 2939// Emit visible names into a debug macinfo section. 2940void DwarfDebug::emitDebugMacInfo() { 2941 if (const MCSection *LineInfo = 2942 Asm->getObjFileLowering().getDwarfMacroInfoSection()) { 2943 // Start the dwarf macinfo section. 2944 Asm->OutStreamer.SwitchSection(LineInfo); 2945 } 2946} 2947 2948// DWARF5 Experimental Separate Dwarf emitters. 2949 2950// This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list, 2951// DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id, 2952// DW_AT_ranges_base, DW_AT_addr_base. 2953CompileUnit *DwarfDebug::constructSkeletonCU(const CompileUnit *CU) { 2954 2955 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit); 2956 CompileUnit *NewCU = new CompileUnit(CU->getUniqueID(), Die, CU->getNode(), 2957 Asm, this, &SkeletonHolder); 2958 2959 NewCU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name, 2960 DICompileUnit(CU->getNode()).getSplitDebugFilename()); 2961 2962 // Relocate to the beginning of the addr_base section, else 0 for the 2963 // beginning of the one for this compile unit. 2964 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2965 NewCU->addLabel(Die, dwarf::DW_AT_GNU_addr_base, dwarf::DW_FORM_sec_offset, 2966 DwarfAddrSectionSym); 2967 else 2968 NewCU->addUInt(Die, dwarf::DW_AT_GNU_addr_base, 2969 dwarf::DW_FORM_sec_offset, 0); 2970 2971 // 2.17.1 requires that we use DW_AT_low_pc for a single entry point 2972 // into an entity. We're using 0, or a NULL label for this. 2973 NewCU->addUInt(Die, dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr, 0); 2974 2975 // DW_AT_stmt_list is a offset of line number information for this 2976 // compile unit in debug_line section. 2977 // FIXME: Should handle multiple compile units. 2978 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2979 NewCU->addLabel(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 2980 DwarfLineSectionSym); 2981 else 2982 NewCU->addUInt(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 0); 2983 2984 if (!CompilationDir.empty()) 2985 NewCU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir); 2986 2987 // Flags to let the linker know we have emitted new style pubnames. 2988 if (GenerateGnuPubSections) { 2989 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2990 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_sec_offset, 2991 Asm->GetTempSymbol("gnu_pubnames", NewCU->getUniqueID())); 2992 else 2993 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_data4, 2994 Asm->GetTempSymbol("gnu_pubnames", NewCU->getUniqueID()), 2995 DwarfGnuPubNamesSectionSym); 2996 2997 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2998 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_sec_offset, 2999 Asm->GetTempSymbol("gnu_pubtypes", NewCU->getUniqueID())); 3000 else 3001 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_data4, 3002 Asm->GetTempSymbol("gnu_pubtypes", NewCU->getUniqueID()), 3003 DwarfGnuPubTypesSectionSym); 3004 } 3005 3006 // Flag if we've emitted any ranges and their location for the compile unit. 3007 if (DebugRangeSymbols.size()) { 3008 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 3009 NewCU->addLabel(Die, dwarf::DW_AT_GNU_ranges_base, 3010 dwarf::DW_FORM_sec_offset, DwarfDebugRangeSectionSym); 3011 else 3012 NewCU->addUInt(Die, dwarf::DW_AT_GNU_ranges_base, dwarf::DW_FORM_data4, 3013 0); 3014 } 3015 3016 SkeletonHolder.addUnit(NewCU); 3017 SkeletonCUs.push_back(NewCU); 3018 3019 return NewCU; 3020} 3021 3022void DwarfDebug::emitSkeletonAbbrevs(const MCSection *Section) { 3023 assert(useSplitDwarf() && "No split dwarf debug info?"); 3024 emitAbbrevs(Section, &SkeletonAbbrevs); 3025} 3026 3027// Emit the .debug_info.dwo section for separated dwarf. This contains the 3028// compile units that would normally be in debug_info. 3029void DwarfDebug::emitDebugInfoDWO() { 3030 assert(useSplitDwarf() && "No split dwarf debug info?"); 3031 InfoHolder.emitUnits(this, Asm->getObjFileLowering().getDwarfInfoDWOSection(), 3032 Asm->getObjFileLowering().getDwarfAbbrevDWOSection(), 3033 DwarfAbbrevDWOSectionSym); 3034} 3035 3036// Emit the .debug_abbrev.dwo section for separated dwarf. This contains the 3037// abbreviations for the .debug_info.dwo section. 3038void DwarfDebug::emitDebugAbbrevDWO() { 3039 assert(useSplitDwarf() && "No split dwarf?"); 3040 emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection(), 3041 &Abbreviations); 3042} 3043 3044// Emit the .debug_str.dwo section for separated dwarf. This contains the 3045// string section and is identical in format to traditional .debug_str 3046// sections. 3047void DwarfDebug::emitDebugStrDWO() { 3048 assert(useSplitDwarf() && "No split dwarf?"); 3049 const MCSection *OffSec = Asm->getObjFileLowering() 3050 .getDwarfStrOffDWOSection(); 3051 const MCSymbol *StrSym = DwarfStrSectionSym; 3052 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(), 3053 OffSec, StrSym); 3054} 3055