DwarfDebug.cpp revision 87b110ac24063a7a48a9d1273e6db596baab78a0
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 and older gdb compatibility 200 // for Darwin by default, pubnames by default for non-Darwin, 201 // and handle split dwarf. 202 bool IsDarwin = Triple(A->getTargetTriple()).isOSDarwin(); 203 204 if (DwarfAccelTables == Default) 205 HasDwarfAccelTables = IsDarwin; 206 else 207 HasDwarfAccelTables = DwarfAccelTables == Enable; 208 209 if (SplitDwarf == Default) 210 HasSplitDwarf = false; 211 else 212 HasSplitDwarf = SplitDwarf == Enable; 213 214 if (DwarfPubSections == Default) 215 HasDwarfPubSections = !IsDarwin; 216 else 217 HasDwarfPubSections = DwarfPubSections == Enable; 218 219 DwarfVersion = getDwarfVersionFromModule(MMI->getModule()); 220 221 { 222 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 223 beginModule(); 224 } 225} 226DwarfDebug::~DwarfDebug() { 227} 228 229// Switch to the specified MCSection and emit an assembler 230// temporary label to it if SymbolStem is specified. 231static MCSymbol *emitSectionSym(AsmPrinter *Asm, const MCSection *Section, 232 const char *SymbolStem = 0) { 233 Asm->OutStreamer.SwitchSection(Section); 234 if (!SymbolStem) return 0; 235 236 MCSymbol *TmpSym = Asm->GetTempSymbol(SymbolStem); 237 Asm->OutStreamer.EmitLabel(TmpSym); 238 return TmpSym; 239} 240 241MCSymbol *DwarfUnits::getStringPoolSym() { 242 return Asm->GetTempSymbol(StringPref); 243} 244 245MCSymbol *DwarfUnits::getStringPoolEntry(StringRef Str) { 246 std::pair<MCSymbol*, unsigned> &Entry = 247 StringPool.GetOrCreateValue(Str).getValue(); 248 if (Entry.first) return Entry.first; 249 250 Entry.second = NextStringPoolNumber++; 251 return Entry.first = Asm->GetTempSymbol(StringPref, Entry.second); 252} 253 254unsigned DwarfUnits::getStringPoolIndex(StringRef Str) { 255 std::pair<MCSymbol*, unsigned> &Entry = 256 StringPool.GetOrCreateValue(Str).getValue(); 257 if (Entry.first) return Entry.second; 258 259 Entry.second = NextStringPoolNumber++; 260 Entry.first = Asm->GetTempSymbol(StringPref, Entry.second); 261 return Entry.second; 262} 263 264unsigned DwarfUnits::getAddrPoolIndex(const MCSymbol *Sym) { 265 return getAddrPoolIndex(MCSymbolRefExpr::Create(Sym, Asm->OutContext)); 266} 267 268unsigned DwarfUnits::getAddrPoolIndex(const MCExpr *Sym) { 269 std::pair<DenseMap<const MCExpr *, unsigned>::iterator, bool> P = 270 AddressPool.insert(std::make_pair(Sym, NextAddrPoolNumber)); 271 if (P.second) 272 ++NextAddrPoolNumber; 273 return P.first->second; 274} 275 276// Define a unique number for the abbreviation. 277// 278void DwarfUnits::assignAbbrevNumber(DIEAbbrev &Abbrev) { 279 // Check the set for priors. 280 DIEAbbrev *InSet = AbbreviationsSet->GetOrInsertNode(&Abbrev); 281 282 // If it's newly added. 283 if (InSet == &Abbrev) { 284 // Add to abbreviation list. 285 Abbreviations->push_back(&Abbrev); 286 287 // Assign the vector position + 1 as its number. 288 Abbrev.setNumber(Abbreviations->size()); 289 } else { 290 // Assign existing abbreviation number. 291 Abbrev.setNumber(InSet->getNumber()); 292 } 293} 294 295static bool isObjCClass(StringRef Name) { 296 return Name.startswith("+") || Name.startswith("-"); 297} 298 299static bool hasObjCCategory(StringRef Name) { 300 if (!isObjCClass(Name)) return false; 301 302 return Name.find(") ") != StringRef::npos; 303} 304 305static void getObjCClassCategory(StringRef In, StringRef &Class, 306 StringRef &Category) { 307 if (!hasObjCCategory(In)) { 308 Class = In.slice(In.find('[') + 1, In.find(' ')); 309 Category = ""; 310 return; 311 } 312 313 Class = In.slice(In.find('[') + 1, In.find('(')); 314 Category = In.slice(In.find('[') + 1, In.find(' ')); 315 return; 316} 317 318static StringRef getObjCMethodName(StringRef In) { 319 return In.slice(In.find(' ') + 1, In.find(']')); 320} 321 322// Helper for sorting sections into a stable output order. 323static bool SectionSort(const MCSection *A, const MCSection *B) { 324 std::string LA = (A ? A->getLabelBeginName() : ""); 325 std::string LB = (B ? B->getLabelBeginName() : ""); 326 return LA < LB; 327} 328 329// Add the various names to the Dwarf accelerator table names. 330// TODO: Determine whether or not we should add names for programs 331// that do not have a DW_AT_name or DW_AT_linkage_name field - this 332// is only slightly different than the lookup of non-standard ObjC names. 333static void addSubprogramNames(CompileUnit *TheCU, DISubprogram SP, 334 DIE* Die) { 335 if (!SP.isDefinition()) return; 336 TheCU->addAccelName(SP.getName(), Die); 337 338 // If the linkage name is different than the name, go ahead and output 339 // that as well into the name table. 340 if (SP.getLinkageName() != "" && SP.getName() != SP.getLinkageName()) 341 TheCU->addAccelName(SP.getLinkageName(), Die); 342 343 // If this is an Objective-C selector name add it to the ObjC accelerator 344 // too. 345 if (isObjCClass(SP.getName())) { 346 StringRef Class, Category; 347 getObjCClassCategory(SP.getName(), Class, Category); 348 TheCU->addAccelObjC(Class, Die); 349 if (Category != "") 350 TheCU->addAccelObjC(Category, Die); 351 // Also add the base method name to the name table. 352 TheCU->addAccelName(getObjCMethodName(SP.getName()), Die); 353 } 354} 355 356/// isSubprogramContext - Return true if Context is either a subprogram 357/// or another context nested inside a subprogram. 358bool DwarfDebug::isSubprogramContext(const MDNode *Context) { 359 if (!Context) 360 return false; 361 DIDescriptor D(Context); 362 if (D.isSubprogram()) 363 return true; 364 if (D.isType()) 365 return isSubprogramContext(resolve(DIType(Context).getContext())); 366 return false; 367} 368 369// Find DIE for the given subprogram and attach appropriate DW_AT_low_pc 370// and DW_AT_high_pc attributes. If there are global variables in this 371// scope then create and insert DIEs for these variables. 372DIE *DwarfDebug::updateSubprogramScopeDIE(CompileUnit *SPCU, 373 const MDNode *SPNode) { 374 DIE *SPDie = SPCU->getDIE(SPNode); 375 376 assert(SPDie && "Unable to find subprogram DIE!"); 377 DISubprogram SP(SPNode); 378 379 // If we're updating an abstract DIE, then we will be adding the children and 380 // object pointer later on. But what we don't want to do is process the 381 // concrete DIE twice. 382 if (DIE *AbsSPDIE = AbstractSPDies.lookup(SPNode)) { 383 // Pick up abstract subprogram DIE. 384 SPDie = new DIE(dwarf::DW_TAG_subprogram); 385 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_abstract_origin, AbsSPDIE); 386 SPCU->addDie(SPDie); 387 } else { 388 DISubprogram SPDecl = SP.getFunctionDeclaration(); 389 if (!SPDecl.isSubprogram()) { 390 // There is not any need to generate specification DIE for a function 391 // defined at compile unit level. If a function is defined inside another 392 // function then gdb prefers the definition at top level and but does not 393 // expect specification DIE in parent function. So avoid creating 394 // specification DIE for a function defined inside a function. 395 DIScope SPContext = resolve(SP.getContext()); 396 if (SP.isDefinition() && !SPContext.isCompileUnit() && 397 !SPContext.isFile() && 398 !isSubprogramContext(SPContext)) { 399 SPCU->addFlag(SPDie, dwarf::DW_AT_declaration); 400 401 // Add arguments. 402 DICompositeType SPTy = SP.getType(); 403 DIArray Args = SPTy.getTypeArray(); 404 uint16_t SPTag = SPTy.getTag(); 405 if (SPTag == dwarf::DW_TAG_subroutine_type) 406 for (unsigned i = 1, N = Args.getNumElements(); i < N; ++i) { 407 DIE *Arg = new DIE(dwarf::DW_TAG_formal_parameter); 408 DIType ATy = DIType(Args.getElement(i)); 409 SPCU->addType(Arg, ATy); 410 if (ATy.isArtificial()) 411 SPCU->addFlag(Arg, dwarf::DW_AT_artificial); 412 if (ATy.isObjectPointer()) 413 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_object_pointer, Arg); 414 SPDie->addChild(Arg); 415 } 416 DIE *SPDeclDie = SPDie; 417 SPDie = new DIE(dwarf::DW_TAG_subprogram); 418 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_specification, SPDeclDie); 419 SPCU->addDie(SPDie); 420 } 421 } 422 } 423 424 SPCU->addLabelAddress(SPDie, dwarf::DW_AT_low_pc, 425 Asm->GetTempSymbol("func_begin", 426 Asm->getFunctionNumber())); 427 SPCU->addLabelAddress(SPDie, dwarf::DW_AT_high_pc, 428 Asm->GetTempSymbol("func_end", 429 Asm->getFunctionNumber())); 430 const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo(); 431 MachineLocation Location(RI->getFrameRegister(*Asm->MF)); 432 SPCU->addAddress(SPDie, dwarf::DW_AT_frame_base, Location); 433 434 // Add name to the name table, we do this here because we're guaranteed 435 // to have concrete versions of our DW_TAG_subprogram nodes. 436 addSubprogramNames(SPCU, SP, SPDie); 437 438 return SPDie; 439} 440 441/// Check whether we should create a DIE for the given Scope, return true 442/// if we don't create a DIE (the corresponding DIE is null). 443bool DwarfDebug::isLexicalScopeDIENull(LexicalScope *Scope) { 444 if (Scope->isAbstractScope()) 445 return false; 446 447 // We don't create a DIE if there is no Range. 448 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 449 if (Ranges.empty()) 450 return true; 451 452 if (Ranges.size() > 1) 453 return false; 454 455 // We don't create a DIE if we have a single Range and the end label 456 // is null. 457 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 458 MCSymbol *End = getLabelAfterInsn(RI->second); 459 return !End; 460} 461 462// Construct new DW_TAG_lexical_block for this scope and attach 463// DW_AT_low_pc/DW_AT_high_pc labels. 464DIE *DwarfDebug::constructLexicalScopeDIE(CompileUnit *TheCU, 465 LexicalScope *Scope) { 466 if (isLexicalScopeDIENull(Scope)) 467 return 0; 468 469 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_lexical_block); 470 if (Scope->isAbstractScope()) 471 return ScopeDIE; 472 473 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 474 // If we have multiple ranges, emit them into the range section. 475 if (Ranges.size() > 1) { 476 // .debug_range section has not been laid out yet. Emit offset in 477 // .debug_range as a uint, size 4, for now. emitDIE will handle 478 // DW_AT_ranges appropriately. 479 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_ranges, dwarf::DW_FORM_data4, 480 DebugRangeSymbols.size() 481 * Asm->getDataLayout().getPointerSize()); 482 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 483 RE = Ranges.end(); RI != RE; ++RI) { 484 DebugRangeSymbols.push_back(getLabelBeforeInsn(RI->first)); 485 DebugRangeSymbols.push_back(getLabelAfterInsn(RI->second)); 486 } 487 488 // Terminate the range list. 489 DebugRangeSymbols.push_back(NULL); 490 DebugRangeSymbols.push_back(NULL); 491 return ScopeDIE; 492 } 493 494 // Construct the address range for this DIE. 495 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 496 MCSymbol *Start = getLabelBeforeInsn(RI->first); 497 MCSymbol *End = getLabelAfterInsn(RI->second); 498 assert(End && "End label should not be null!"); 499 500 assert(Start->isDefined() && "Invalid starting label for an inlined scope!"); 501 assert(End->isDefined() && "Invalid end label for an inlined scope!"); 502 503 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_low_pc, Start); 504 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_high_pc, End); 505 506 return ScopeDIE; 507} 508 509// This scope represents inlined body of a function. Construct DIE to 510// represent this concrete inlined copy of the function. 511DIE *DwarfDebug::constructInlinedScopeDIE(CompileUnit *TheCU, 512 LexicalScope *Scope) { 513 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 514 assert(Ranges.empty() == false && 515 "LexicalScope does not have instruction markers!"); 516 517 if (!Scope->getScopeNode()) 518 return NULL; 519 DIScope DS(Scope->getScopeNode()); 520 DISubprogram InlinedSP = getDISubprogram(DS); 521 DIE *OriginDIE = TheCU->getDIE(InlinedSP); 522 if (!OriginDIE) { 523 DEBUG(dbgs() << "Unable to find original DIE for an inlined subprogram."); 524 return NULL; 525 } 526 527 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_inlined_subroutine); 528 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_abstract_origin, OriginDIE); 529 530 if (Ranges.size() > 1) { 531 // .debug_range section has not been laid out yet. Emit offset in 532 // .debug_range as a uint, size 4, for now. emitDIE will handle 533 // DW_AT_ranges appropriately. 534 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_ranges, dwarf::DW_FORM_data4, 535 DebugRangeSymbols.size() 536 * Asm->getDataLayout().getPointerSize()); 537 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 538 RE = Ranges.end(); RI != RE; ++RI) { 539 DebugRangeSymbols.push_back(getLabelBeforeInsn(RI->first)); 540 DebugRangeSymbols.push_back(getLabelAfterInsn(RI->second)); 541 } 542 DebugRangeSymbols.push_back(NULL); 543 DebugRangeSymbols.push_back(NULL); 544 } else { 545 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 546 MCSymbol *StartLabel = getLabelBeforeInsn(RI->first); 547 MCSymbol *EndLabel = getLabelAfterInsn(RI->second); 548 549 if (StartLabel == 0 || EndLabel == 0) 550 llvm_unreachable("Unexpected Start and End labels for an inlined scope!"); 551 552 assert(StartLabel->isDefined() && 553 "Invalid starting label for an inlined scope!"); 554 assert(EndLabel->isDefined() && "Invalid end label for an inlined scope!"); 555 556 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_low_pc, StartLabel); 557 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_high_pc, EndLabel); 558 } 559 560 InlinedSubprogramDIEs.insert(OriginDIE); 561 562 // Add the call site information to the DIE. 563 DILocation DL(Scope->getInlinedAt()); 564 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_file, 0, 565 getOrCreateSourceID(DL.getFilename(), DL.getDirectory(), 566 TheCU->getUniqueID())); 567 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_line, 0, DL.getLineNumber()); 568 569 // Add name to the name table, we do this here because we're guaranteed 570 // to have concrete versions of our DW_TAG_inlined_subprogram nodes. 571 addSubprogramNames(TheCU, InlinedSP, ScopeDIE); 572 573 return ScopeDIE; 574} 575 576DIE *DwarfDebug::createScopeChildrenDIE(CompileUnit *TheCU, LexicalScope *Scope, 577 SmallVectorImpl<DIE*> &Children) { 578 DIE *ObjectPointer = NULL; 579 580 // Collect arguments for current function. 581 if (LScopes.isCurrentFunctionScope(Scope)) 582 for (unsigned i = 0, N = CurrentFnArguments.size(); i < N; ++i) 583 if (DbgVariable *ArgDV = CurrentFnArguments[i]) 584 if (DIE *Arg = 585 TheCU->constructVariableDIE(ArgDV, Scope->isAbstractScope())) { 586 Children.push_back(Arg); 587 if (ArgDV->isObjectPointer()) ObjectPointer = Arg; 588 } 589 590 // Collect lexical scope children first. 591 const SmallVectorImpl<DbgVariable *> &Variables =ScopeVariables.lookup(Scope); 592 for (unsigned i = 0, N = Variables.size(); i < N; ++i) 593 if (DIE *Variable = 594 TheCU->constructVariableDIE(Variables[i], Scope->isAbstractScope())) { 595 Children.push_back(Variable); 596 if (Variables[i]->isObjectPointer()) ObjectPointer = Variable; 597 } 598 const SmallVectorImpl<LexicalScope *> &Scopes = Scope->getChildren(); 599 for (unsigned j = 0, M = Scopes.size(); j < M; ++j) 600 if (DIE *Nested = constructScopeDIE(TheCU, Scopes[j])) 601 Children.push_back(Nested); 602 return ObjectPointer; 603} 604 605// Construct a DIE for this scope. 606DIE *DwarfDebug::constructScopeDIE(CompileUnit *TheCU, LexicalScope *Scope) { 607 if (!Scope || !Scope->getScopeNode()) 608 return NULL; 609 610 DIScope DS(Scope->getScopeNode()); 611 612 SmallVector<DIE *, 8> Children; 613 DIE *ObjectPointer = NULL; 614 bool ChildrenCreated = false; 615 616 // We try to create the scope DIE first, then the children DIEs. This will 617 // avoid creating un-used children then removing them later when we find out 618 // the scope DIE is null. 619 DIE *ScopeDIE = NULL; 620 if (Scope->getInlinedAt()) 621 ScopeDIE = constructInlinedScopeDIE(TheCU, Scope); 622 else if (DS.isSubprogram()) { 623 ProcessedSPNodes.insert(DS); 624 if (Scope->isAbstractScope()) { 625 ScopeDIE = TheCU->getDIE(DS); 626 // Note down abstract DIE. 627 if (ScopeDIE) 628 AbstractSPDies.insert(std::make_pair(DS, ScopeDIE)); 629 } 630 else 631 ScopeDIE = updateSubprogramScopeDIE(TheCU, DS); 632 } 633 else { 634 // Early exit when we know the scope DIE is going to be null. 635 if (isLexicalScopeDIENull(Scope)) 636 return NULL; 637 638 // We create children here when we know the scope DIE is not going to be 639 // null and the children will be added to the scope DIE. 640 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children); 641 ChildrenCreated = true; 642 643 // There is no need to emit empty lexical block DIE. 644 std::pair<ImportedEntityMap::const_iterator, 645 ImportedEntityMap::const_iterator> Range = std::equal_range( 646 ScopesWithImportedEntities.begin(), ScopesWithImportedEntities.end(), 647 std::pair<const MDNode *, const MDNode *>(DS, (const MDNode*)0), 648 less_first()); 649 if (Children.empty() && Range.first == Range.second) 650 return NULL; 651 ScopeDIE = constructLexicalScopeDIE(TheCU, Scope); 652 assert(ScopeDIE && "Scope DIE should not be null."); 653 for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second; 654 ++i) 655 constructImportedEntityDIE(TheCU, i->second, ScopeDIE); 656 } 657 658 if (!ScopeDIE) { 659 assert(Children.empty() && 660 "We create children only when the scope DIE is not null."); 661 return NULL; 662 } 663 if (!ChildrenCreated) 664 // We create children when the scope DIE is not null. 665 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children); 666 667 // Add children 668 for (SmallVectorImpl<DIE *>::iterator I = Children.begin(), 669 E = Children.end(); I != E; ++I) 670 ScopeDIE->addChild(*I); 671 672 if (DS.isSubprogram() && ObjectPointer != NULL) 673 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, ObjectPointer); 674 675 if (DS.isSubprogram()) 676 TheCU->addPubTypes(DISubprogram(DS)); 677 678 return ScopeDIE; 679} 680 681// Look up the source id with the given directory and source file names. 682// If none currently exists, create a new id and insert it in the 683// SourceIds map. This can update DirectoryNames and SourceFileNames maps 684// as well. 685unsigned DwarfDebug::getOrCreateSourceID(StringRef FileName, 686 StringRef DirName, unsigned CUID) { 687 // If we use .loc in assembly, we can't separate .file entries according to 688 // compile units. Thus all files will belong to the default compile unit. 689 690 // FIXME: add a better feature test than hasRawTextSupport. Even better, 691 // extend .file to support this. 692 if (Asm->TM.hasMCUseLoc() && Asm->OutStreamer.hasRawTextSupport()) 693 CUID = 0; 694 695 // If FE did not provide a file name, then assume stdin. 696 if (FileName.empty()) 697 return getOrCreateSourceID("<stdin>", StringRef(), CUID); 698 699 // TODO: this might not belong here. See if we can factor this better. 700 if (DirName == CompilationDir) 701 DirName = ""; 702 703 // FileIDCUMap stores the current ID for the given compile unit. 704 unsigned SrcId = FileIDCUMap[CUID] + 1; 705 706 // We look up the CUID/file/dir by concatenating them with a zero byte. 707 SmallString<128> NamePair; 708 NamePair += utostr(CUID); 709 NamePair += '\0'; 710 NamePair += DirName; 711 NamePair += '\0'; // Zero bytes are not allowed in paths. 712 NamePair += FileName; 713 714 StringMapEntry<unsigned> &Ent = SourceIdMap.GetOrCreateValue(NamePair, SrcId); 715 if (Ent.getValue() != SrcId) 716 return Ent.getValue(); 717 718 FileIDCUMap[CUID] = SrcId; 719 // Print out a .file directive to specify files for .loc directives. 720 Asm->OutStreamer.EmitDwarfFileDirective(SrcId, DirName, FileName, CUID); 721 722 return SrcId; 723} 724 725// Create new CompileUnit for the given metadata node with tag 726// DW_TAG_compile_unit. 727CompileUnit *DwarfDebug::constructCompileUnit(const MDNode *N) { 728 DICompileUnit DIUnit(N); 729 StringRef FN = DIUnit.getFilename(); 730 CompilationDir = DIUnit.getDirectory(); 731 732 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit); 733 CompileUnit *NewCU = 734 new CompileUnit(GlobalCUIndexCount++, Die, N, Asm, this, &InfoHolder); 735 736 FileIDCUMap[NewCU->getUniqueID()] = 0; 737 // Call this to emit a .file directive if it wasn't emitted for the source 738 // file this CU comes from yet. 739 getOrCreateSourceID(FN, CompilationDir, NewCU->getUniqueID()); 740 741 NewCU->addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer()); 742 NewCU->addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2, 743 DIUnit.getLanguage()); 744 NewCU->addString(Die, dwarf::DW_AT_name, FN); 745 746 // 2.17.1 requires that we use DW_AT_low_pc for a single entry point 747 // into an entity. We're using 0 (or a NULL label) for this. For 748 // split dwarf it's in the skeleton CU so omit it here. 749 if (!useSplitDwarf()) 750 NewCU->addLabelAddress(Die, dwarf::DW_AT_low_pc, NULL); 751 752 // Define start line table label for each Compile Unit. 753 MCSymbol *LineTableStartSym = Asm->GetTempSymbol("line_table_start", 754 NewCU->getUniqueID()); 755 Asm->OutStreamer.getContext().setMCLineTableSymbol(LineTableStartSym, 756 NewCU->getUniqueID()); 757 758 // Use a single line table if we are using .loc and generating assembly. 759 bool UseTheFirstCU = 760 (Asm->TM.hasMCUseLoc() && Asm->OutStreamer.hasRawTextSupport()) || 761 (NewCU->getUniqueID() == 0); 762 763 if (!useSplitDwarf()) { 764 // DW_AT_stmt_list is a offset of line number information for this 765 // compile unit in debug_line section. For split dwarf this is 766 // left in the skeleton CU and so not included. 767 // The line table entries are not always emitted in assembly, so it 768 // is not okay to use line_table_start here. 769 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 770 NewCU->addLabel(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 771 UseTheFirstCU ? Asm->GetTempSymbol("section_line") 772 : LineTableStartSym); 773 else if (UseTheFirstCU) 774 NewCU->addUInt(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4, 0); 775 else 776 NewCU->addDelta(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4, 777 LineTableStartSym, DwarfLineSectionSym); 778 779 // If we're using split dwarf the compilation dir is going to be in the 780 // skeleton CU and so we don't need to duplicate it here. 781 if (!CompilationDir.empty()) 782 NewCU->addString(Die, dwarf::DW_AT_comp_dir, CompilationDir); 783 784 // Flags to let the linker know we have emitted new style pubnames. Only 785 // emit it here if we don't have a skeleton CU for split dwarf. 786 if (GenerateGnuPubSections) { 787 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 788 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubnames, 789 dwarf::DW_FORM_sec_offset, 790 Asm->GetTempSymbol("gnu_pubnames", 791 NewCU->getUniqueID())); 792 else 793 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_data4, 794 Asm->GetTempSymbol("gnu_pubnames", 795 NewCU->getUniqueID()), 796 DwarfGnuPubNamesSectionSym); 797 798 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 799 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubtypes, 800 dwarf::DW_FORM_sec_offset, 801 Asm->GetTempSymbol("gnu_pubtypes", 802 NewCU->getUniqueID())); 803 else 804 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_data4, 805 Asm->GetTempSymbol("gnu_pubtypes", 806 NewCU->getUniqueID()), 807 DwarfGnuPubTypesSectionSym); 808 } 809 } 810 811 if (DIUnit.isOptimized()) 812 NewCU->addFlag(Die, dwarf::DW_AT_APPLE_optimized); 813 814 StringRef Flags = DIUnit.getFlags(); 815 if (!Flags.empty()) 816 NewCU->addString(Die, dwarf::DW_AT_APPLE_flags, Flags); 817 818 if (unsigned RVer = DIUnit.getRunTimeVersion()) 819 NewCU->addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers, 820 dwarf::DW_FORM_data1, RVer); 821 822 if (!FirstCU) 823 FirstCU = NewCU; 824 825 InfoHolder.addUnit(NewCU); 826 827 CUMap.insert(std::make_pair(N, NewCU)); 828 return NewCU; 829} 830 831// Construct subprogram DIE. 832void DwarfDebug::constructSubprogramDIE(CompileUnit *TheCU, 833 const MDNode *N) { 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); 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, 0, FileID); 890 TheCU->addUInt(IMDie, dwarf::DW_AT_decl_line, 0, 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, 0, 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, 0, 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 DenseMap<const MDNode *, LexicalScope *> DeadFnScopeMap; 973 974 if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) { 975 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) { 976 DICompileUnit TheCU(CU_Nodes->getOperand(i)); 977 DIArray Subprograms = TheCU.getSubprograms(); 978 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) { 979 DISubprogram SP(Subprograms.getElement(i)); 980 if (ProcessedSPNodes.count(SP) != 0) continue; 981 if (!SP.isSubprogram()) continue; 982 if (!SP.isDefinition()) continue; 983 DIArray Variables = SP.getVariables(); 984 if (Variables.getNumElements() == 0) continue; 985 986 LexicalScope *Scope = 987 new LexicalScope(NULL, DIDescriptor(SP), NULL, false); 988 DeadFnScopeMap[SP] = Scope; 989 990 // Construct subprogram DIE and add variables DIEs. 991 CompileUnit *SPCU = CUMap.lookup(TheCU); 992 assert(SPCU && "Unable to find Compile Unit!"); 993 constructSubprogramDIE(SPCU, SP); 994 DIE *ScopeDIE = SPCU->getDIE(SP); 995 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) { 996 DIVariable DV(Variables.getElement(vi)); 997 if (!DV.isVariable()) continue; 998 DbgVariable NewVar(DV, NULL, this); 999 if (DIE *VariableDIE = 1000 SPCU->constructVariableDIE(&NewVar, Scope->isAbstractScope())) 1001 ScopeDIE->addChild(VariableDIE); 1002 } 1003 } 1004 } 1005 } 1006 DeleteContainerSeconds(DeadFnScopeMap); 1007} 1008 1009// Type Signature [7.27] and ODR Hash code. 1010 1011/// \brief Grabs the string in whichever attribute is passed in and returns 1012/// a reference to it. Returns "" if the attribute doesn't exist. 1013static StringRef getDIEStringAttr(DIE *Die, unsigned Attr) { 1014 DIEValue *V = Die->findAttribute(Attr); 1015 1016 if (DIEString *S = dyn_cast_or_null<DIEString>(V)) 1017 return S->getString(); 1018 1019 return StringRef(""); 1020} 1021 1022/// Return true if the current DIE is contained within an anonymous namespace. 1023static bool isContainedInAnonNamespace(DIE *Die) { 1024 DIE *Parent = Die->getParent(); 1025 1026 while (Parent) { 1027 if (Parent->getTag() == dwarf::DW_TAG_namespace && 1028 getDIEStringAttr(Parent, dwarf::DW_AT_name) == "") 1029 return true; 1030 Parent = Parent->getParent(); 1031 } 1032 1033 return false; 1034} 1035 1036/// Test if the current CU language is C++ and that we have 1037/// a named type that is not contained in an anonymous namespace. 1038static bool shouldAddODRHash(CompileUnit *CU, DIE *Die) { 1039 return CU->getLanguage() == dwarf::DW_LANG_C_plus_plus && 1040 getDIEStringAttr(Die, dwarf::DW_AT_name) != "" && 1041 !isContainedInAnonNamespace(Die); 1042} 1043 1044void DwarfDebug::finalizeModuleInfo() { 1045 // Collect info for variables that were optimized out. 1046 collectDeadVariables(); 1047 1048 // Attach DW_AT_inline attribute with inlined subprogram DIEs. 1049 computeInlinedDIEs(); 1050 1051 // Split out type units and conditionally add an ODR tag to the split 1052 // out type. 1053 // FIXME: Do type splitting. 1054 for (unsigned i = 0, e = TypeUnits.size(); i != e; ++i) { 1055 DIE *Die = TypeUnits[i]; 1056 DIEHash Hash; 1057 // If we've requested ODR hashes and it's applicable for an ODR hash then 1058 // add the ODR signature now. 1059 // FIXME: This should be added onto the type unit, not the type, but this 1060 // works as an intermediate stage. 1061 if (GenerateODRHash && shouldAddODRHash(CUMap.begin()->second, Die)) 1062 CUMap.begin()->second->addUInt(Die, dwarf::DW_AT_GNU_odr_signature, 1063 dwarf::DW_FORM_data8, 1064 Hash.computeDIEODRSignature(Die)); 1065 } 1066 1067 // Handle anything that needs to be done on a per-cu basis. 1068 for (DenseMap<const MDNode *, CompileUnit *>::iterator CUI = CUMap.begin(), 1069 CUE = CUMap.end(); 1070 CUI != CUE; ++CUI) { 1071 CompileUnit *TheCU = CUI->second; 1072 // Emit DW_AT_containing_type attribute to connect types with their 1073 // vtable holding type. 1074 TheCU->constructContainingTypeDIEs(); 1075 1076 // If we're splitting the dwarf out now that we've got the entire 1077 // CU then construct a skeleton CU based upon it. 1078 if (useSplitDwarf()) { 1079 uint64_t ID = 0; 1080 if (GenerateCUHash) { 1081 DIEHash CUHash; 1082 ID = CUHash.computeCUSignature(TheCU->getCUDie()); 1083 } 1084 // This should be a unique identifier when we want to build .dwp files. 1085 TheCU->addUInt(TheCU->getCUDie(), dwarf::DW_AT_GNU_dwo_id, 1086 dwarf::DW_FORM_data8, ID); 1087 // Now construct the skeleton CU associated. 1088 CompileUnit *SkCU = constructSkeletonCU(TheCU); 1089 // This should be a unique identifier when we want to build .dwp files. 1090 SkCU->addUInt(SkCU->getCUDie(), dwarf::DW_AT_GNU_dwo_id, 1091 dwarf::DW_FORM_data8, ID); 1092 } 1093 } 1094 1095 // Compute DIE offsets and sizes. 1096 InfoHolder.computeSizeAndOffsets(); 1097 if (useSplitDwarf()) 1098 SkeletonHolder.computeSizeAndOffsets(); 1099} 1100 1101void DwarfDebug::endSections() { 1102 // Filter labels by section. 1103 for (size_t n = 0; n < ArangeLabels.size(); n++) { 1104 const SymbolCU &SCU = ArangeLabels[n]; 1105 if (SCU.Sym->isInSection()) { 1106 // Make a note of this symbol and it's section. 1107 const MCSection *Section = &SCU.Sym->getSection(); 1108 if (!Section->getKind().isMetadata()) 1109 SectionMap[Section].push_back(SCU); 1110 } else { 1111 // Some symbols (e.g. common/bss on mach-o) can have no section but still 1112 // appear in the output. This sucks as we rely on sections to build 1113 // arange spans. We can do it without, but it's icky. 1114 SectionMap[NULL].push_back(SCU); 1115 } 1116 } 1117 1118 // Build a list of sections used. 1119 std::vector<const MCSection *> Sections; 1120 for (SectionMapType::iterator it = SectionMap.begin(); it != SectionMap.end(); 1121 it++) { 1122 const MCSection *Section = it->first; 1123 Sections.push_back(Section); 1124 } 1125 1126 // Sort the sections into order. 1127 // This is only done to ensure consistent output order across different runs. 1128 std::sort(Sections.begin(), Sections.end(), SectionSort); 1129 1130 // Add terminating symbols for each section. 1131 for (unsigned ID=0;ID<Sections.size();ID++) { 1132 const MCSection *Section = Sections[ID]; 1133 MCSymbol *Sym = NULL; 1134 1135 if (Section) { 1136 // We can't call MCSection::getLabelEndName, as it's only safe to do so 1137 // if we know the section name up-front. For user-created sections, the resulting 1138 // label may not be valid to use as a label. (section names can use a greater 1139 // set of characters on some systems) 1140 Sym = Asm->GetTempSymbol("debug_end", ID); 1141 Asm->OutStreamer.SwitchSection(Section); 1142 Asm->OutStreamer.EmitLabel(Sym); 1143 } 1144 1145 // Insert a final terminator. 1146 SectionMap[Section].push_back(SymbolCU(NULL, Sym)); 1147 } 1148} 1149 1150// Emit all Dwarf sections that should come after the content. 1151void DwarfDebug::endModule() { 1152 1153 if (!FirstCU) return; 1154 1155 // End any existing sections. 1156 // TODO: Does this need to happen? 1157 endSections(); 1158 1159 // Finalize the debug info for the module. 1160 finalizeModuleInfo(); 1161 1162 if (!useSplitDwarf()) { 1163 emitDebugStr(); 1164 1165 // Emit all the DIEs into a debug info section. 1166 emitDebugInfo(); 1167 1168 // Corresponding abbreviations into a abbrev section. 1169 emitAbbreviations(); 1170 1171 // Emit info into a debug loc section. 1172 emitDebugLoc(); 1173 1174 // Emit info into a debug aranges section. 1175 emitDebugARanges(); 1176 1177 // Emit info into a debug ranges section. 1178 emitDebugRanges(); 1179 1180 // Emit info into a debug macinfo section. 1181 emitDebugMacInfo(); 1182 1183 } else { 1184 // TODO: Fill this in for separated debug sections and separate 1185 // out information into new sections. 1186 emitDebugStr(); 1187 if (useSplitDwarf()) 1188 emitDebugStrDWO(); 1189 1190 // Emit the debug info section and compile units. 1191 emitDebugInfo(); 1192 emitDebugInfoDWO(); 1193 1194 // Corresponding abbreviations into a abbrev section. 1195 emitAbbreviations(); 1196 emitDebugAbbrevDWO(); 1197 1198 // Emit info into a debug loc section. 1199 emitDebugLoc(); 1200 1201 // Emit info into a debug aranges section. 1202 emitDebugARanges(); 1203 1204 // Emit info into a debug ranges section. 1205 emitDebugRanges(); 1206 1207 // Emit info into a debug macinfo section. 1208 emitDebugMacInfo(); 1209 1210 // Emit DWO addresses. 1211 InfoHolder.emitAddresses(Asm->getObjFileLowering().getDwarfAddrSection()); 1212 1213 } 1214 1215 // Emit info into the dwarf accelerator table sections. 1216 if (useDwarfAccelTables()) { 1217 emitAccelNames(); 1218 emitAccelObjC(); 1219 emitAccelNamespaces(); 1220 emitAccelTypes(); 1221 } 1222 1223 // Emit the pubnames and pubtypes sections if requested. 1224 if (HasDwarfPubSections) { 1225 emitDebugPubNames(GenerateGnuPubSections); 1226 emitDebugPubTypes(GenerateGnuPubSections); 1227 } 1228 1229 // clean up. 1230 SPMap.clear(); 1231 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 1232 E = CUMap.end(); I != E; ++I) 1233 delete I->second; 1234 1235 for (SmallVectorImpl<CompileUnit *>::iterator I = SkeletonCUs.begin(), 1236 E = SkeletonCUs.end(); I != E; ++I) 1237 delete *I; 1238 1239 // Reset these for the next Module if we have one. 1240 FirstCU = NULL; 1241} 1242 1243// Find abstract variable, if any, associated with Var. 1244DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &DV, 1245 DebugLoc ScopeLoc) { 1246 LLVMContext &Ctx = DV->getContext(); 1247 // More then one inlined variable corresponds to one abstract variable. 1248 DIVariable Var = cleanseInlinedVariable(DV, Ctx); 1249 DbgVariable *AbsDbgVariable = AbstractVariables.lookup(Var); 1250 if (AbsDbgVariable) 1251 return AbsDbgVariable; 1252 1253 LexicalScope *Scope = LScopes.findAbstractScope(ScopeLoc.getScope(Ctx)); 1254 if (!Scope) 1255 return NULL; 1256 1257 AbsDbgVariable = new DbgVariable(Var, NULL, this); 1258 addScopeVariable(Scope, AbsDbgVariable); 1259 AbstractVariables[Var] = AbsDbgVariable; 1260 return AbsDbgVariable; 1261} 1262 1263// If Var is a current function argument then add it to CurrentFnArguments list. 1264bool DwarfDebug::addCurrentFnArgument(const MachineFunction *MF, 1265 DbgVariable *Var, LexicalScope *Scope) { 1266 if (!LScopes.isCurrentFunctionScope(Scope)) 1267 return false; 1268 DIVariable DV = Var->getVariable(); 1269 if (DV.getTag() != dwarf::DW_TAG_arg_variable) 1270 return false; 1271 unsigned ArgNo = DV.getArgNumber(); 1272 if (ArgNo == 0) 1273 return false; 1274 1275 size_t Size = CurrentFnArguments.size(); 1276 if (Size == 0) 1277 CurrentFnArguments.resize(MF->getFunction()->arg_size()); 1278 // llvm::Function argument size is not good indicator of how many 1279 // arguments does the function have at source level. 1280 if (ArgNo > Size) 1281 CurrentFnArguments.resize(ArgNo * 2); 1282 CurrentFnArguments[ArgNo - 1] = Var; 1283 return true; 1284} 1285 1286// Collect variable information from side table maintained by MMI. 1287void 1288DwarfDebug::collectVariableInfoFromMMITable(const MachineFunction *MF, 1289 SmallPtrSet<const MDNode *, 16> &Processed) { 1290 MachineModuleInfo::VariableDbgInfoMapTy &VMap = MMI->getVariableDbgInfo(); 1291 for (MachineModuleInfo::VariableDbgInfoMapTy::iterator VI = VMap.begin(), 1292 VE = VMap.end(); VI != VE; ++VI) { 1293 const MDNode *Var = VI->first; 1294 if (!Var) continue; 1295 Processed.insert(Var); 1296 DIVariable DV(Var); 1297 const std::pair<unsigned, DebugLoc> &VP = VI->second; 1298 1299 LexicalScope *Scope = LScopes.findLexicalScope(VP.second); 1300 1301 // If variable scope is not found then skip this variable. 1302 if (Scope == 0) 1303 continue; 1304 1305 DbgVariable *AbsDbgVariable = findAbstractVariable(DV, VP.second); 1306 DbgVariable *RegVar = new DbgVariable(DV, AbsDbgVariable, this); 1307 RegVar->setFrameIndex(VP.first); 1308 if (!addCurrentFnArgument(MF, RegVar, Scope)) 1309 addScopeVariable(Scope, RegVar); 1310 if (AbsDbgVariable) 1311 AbsDbgVariable->setFrameIndex(VP.first); 1312 } 1313} 1314 1315// Return true if debug value, encoded by DBG_VALUE instruction, is in a 1316// defined reg. 1317static bool isDbgValueInDefinedReg(const MachineInstr *MI) { 1318 assert(MI->isDebugValue() && "Invalid DBG_VALUE machine instruction!"); 1319 return MI->getNumOperands() == 3 && 1320 MI->getOperand(0).isReg() && MI->getOperand(0).getReg() && 1321 (MI->getOperand(1).isImm() || 1322 (MI->getOperand(1).isReg() && MI->getOperand(1).getReg() == 0U)); 1323} 1324 1325// Get .debug_loc entry for the instruction range starting at MI. 1326static DotDebugLocEntry getDebugLocEntry(AsmPrinter *Asm, 1327 const MCSymbol *FLabel, 1328 const MCSymbol *SLabel, 1329 const MachineInstr *MI) { 1330 const MDNode *Var = MI->getOperand(MI->getNumOperands() - 1).getMetadata(); 1331 1332 assert(MI->getNumOperands() == 3); 1333 if (MI->getOperand(0).isReg()) { 1334 MachineLocation MLoc; 1335 // If the second operand is an immediate, this is a 1336 // register-indirect address. 1337 if (!MI->getOperand(1).isImm()) 1338 MLoc.set(MI->getOperand(0).getReg()); 1339 else 1340 MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm()); 1341 return DotDebugLocEntry(FLabel, SLabel, MLoc, Var); 1342 } 1343 if (MI->getOperand(0).isImm()) 1344 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getImm()); 1345 if (MI->getOperand(0).isFPImm()) 1346 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getFPImm()); 1347 if (MI->getOperand(0).isCImm()) 1348 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getCImm()); 1349 1350 llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!"); 1351} 1352 1353// Find variables for each lexical scope. 1354void 1355DwarfDebug::collectVariableInfo(const MachineFunction *MF, 1356 SmallPtrSet<const MDNode *, 16> &Processed) { 1357 1358 // Grab the variable info that was squirreled away in the MMI side-table. 1359 collectVariableInfoFromMMITable(MF, Processed); 1360 1361 for (SmallVectorImpl<const MDNode*>::const_iterator 1362 UVI = UserVariables.begin(), UVE = UserVariables.end(); UVI != UVE; 1363 ++UVI) { 1364 const MDNode *Var = *UVI; 1365 if (Processed.count(Var)) 1366 continue; 1367 1368 // History contains relevant DBG_VALUE instructions for Var and instructions 1369 // clobbering it. 1370 SmallVectorImpl<const MachineInstr*> &History = DbgValues[Var]; 1371 if (History.empty()) 1372 continue; 1373 const MachineInstr *MInsn = History.front(); 1374 1375 DIVariable DV(Var); 1376 LexicalScope *Scope = NULL; 1377 if (DV.getTag() == dwarf::DW_TAG_arg_variable && 1378 DISubprogram(DV.getContext()).describes(MF->getFunction())) 1379 Scope = LScopes.getCurrentFunctionScope(); 1380 else if (MDNode *IA = DV.getInlinedAt()) 1381 Scope = LScopes.findInlinedScope(DebugLoc::getFromDILocation(IA)); 1382 else 1383 Scope = LScopes.findLexicalScope(cast<MDNode>(DV->getOperand(1))); 1384 // If variable scope is not found then skip this variable. 1385 if (!Scope) 1386 continue; 1387 1388 Processed.insert(DV); 1389 assert(MInsn->isDebugValue() && "History must begin with debug value"); 1390 DbgVariable *AbsVar = findAbstractVariable(DV, MInsn->getDebugLoc()); 1391 DbgVariable *RegVar = new DbgVariable(DV, AbsVar, this); 1392 if (!addCurrentFnArgument(MF, RegVar, Scope)) 1393 addScopeVariable(Scope, RegVar); 1394 if (AbsVar) 1395 AbsVar->setMInsn(MInsn); 1396 1397 // Simplify ranges that are fully coalesced. 1398 if (History.size() <= 1 || (History.size() == 2 && 1399 MInsn->isIdenticalTo(History.back()))) { 1400 RegVar->setMInsn(MInsn); 1401 continue; 1402 } 1403 1404 // Handle multiple DBG_VALUE instructions describing one variable. 1405 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size()); 1406 1407 for (SmallVectorImpl<const MachineInstr*>::const_iterator 1408 HI = History.begin(), HE = History.end(); HI != HE; ++HI) { 1409 const MachineInstr *Begin = *HI; 1410 assert(Begin->isDebugValue() && "Invalid History entry"); 1411 1412 // Check if DBG_VALUE is truncating a range. 1413 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() 1414 && !Begin->getOperand(0).getReg()) 1415 continue; 1416 1417 // Compute the range for a register location. 1418 const MCSymbol *FLabel = getLabelBeforeInsn(Begin); 1419 const MCSymbol *SLabel = 0; 1420 1421 if (HI + 1 == HE) 1422 // If Begin is the last instruction in History then its value is valid 1423 // until the end of the function. 1424 SLabel = FunctionEndSym; 1425 else { 1426 const MachineInstr *End = HI[1]; 1427 DEBUG(dbgs() << "DotDebugLoc Pair:\n" 1428 << "\t" << *Begin << "\t" << *End << "\n"); 1429 if (End->isDebugValue()) 1430 SLabel = getLabelBeforeInsn(End); 1431 else { 1432 // End is a normal instruction clobbering the range. 1433 SLabel = getLabelAfterInsn(End); 1434 assert(SLabel && "Forgot label after clobber instruction"); 1435 ++HI; 1436 } 1437 } 1438 1439 // The value is valid until the next DBG_VALUE or clobber. 1440 DotDebugLocEntries.push_back(getDebugLocEntry(Asm, FLabel, SLabel, 1441 Begin)); 1442 } 1443 DotDebugLocEntries.push_back(DotDebugLocEntry()); 1444 } 1445 1446 // Collect info for variables that were optimized out. 1447 LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); 1448 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables(); 1449 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) { 1450 DIVariable DV(Variables.getElement(i)); 1451 if (!DV || !DV.isVariable() || !Processed.insert(DV)) 1452 continue; 1453 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext())) 1454 addScopeVariable(Scope, new DbgVariable(DV, NULL, this)); 1455 } 1456} 1457 1458// Return Label preceding the instruction. 1459MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) { 1460 MCSymbol *Label = LabelsBeforeInsn.lookup(MI); 1461 assert(Label && "Didn't insert label before instruction"); 1462 return Label; 1463} 1464 1465// Return Label immediately following the instruction. 1466MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) { 1467 return LabelsAfterInsn.lookup(MI); 1468} 1469 1470// Process beginning of an instruction. 1471void DwarfDebug::beginInstruction(const MachineInstr *MI) { 1472 // Check if source location changes, but ignore DBG_VALUE locations. 1473 if (!MI->isDebugValue()) { 1474 DebugLoc DL = MI->getDebugLoc(); 1475 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) { 1476 unsigned Flags = 0; 1477 PrevInstLoc = DL; 1478 if (DL == PrologEndLoc) { 1479 Flags |= DWARF2_FLAG_PROLOGUE_END; 1480 PrologEndLoc = DebugLoc(); 1481 } 1482 if (PrologEndLoc.isUnknown()) 1483 Flags |= DWARF2_FLAG_IS_STMT; 1484 1485 if (!DL.isUnknown()) { 1486 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext()); 1487 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags); 1488 } else 1489 recordSourceLine(0, 0, 0, 0); 1490 } 1491 } 1492 1493 // Insert labels where requested. 1494 DenseMap<const MachineInstr*, MCSymbol*>::iterator I = 1495 LabelsBeforeInsn.find(MI); 1496 1497 // No label needed. 1498 if (I == LabelsBeforeInsn.end()) 1499 return; 1500 1501 // Label already assigned. 1502 if (I->second) 1503 return; 1504 1505 if (!PrevLabel) { 1506 PrevLabel = MMI->getContext().CreateTempSymbol(); 1507 Asm->OutStreamer.EmitLabel(PrevLabel); 1508 } 1509 I->second = PrevLabel; 1510} 1511 1512// Process end of an instruction. 1513void DwarfDebug::endInstruction(const MachineInstr *MI) { 1514 // Don't create a new label after DBG_VALUE instructions. 1515 // They don't generate code. 1516 if (!MI->isDebugValue()) 1517 PrevLabel = 0; 1518 1519 DenseMap<const MachineInstr*, MCSymbol*>::iterator I = 1520 LabelsAfterInsn.find(MI); 1521 1522 // No label needed. 1523 if (I == LabelsAfterInsn.end()) 1524 return; 1525 1526 // Label already assigned. 1527 if (I->second) 1528 return; 1529 1530 // We need a label after this instruction. 1531 if (!PrevLabel) { 1532 PrevLabel = MMI->getContext().CreateTempSymbol(); 1533 Asm->OutStreamer.EmitLabel(PrevLabel); 1534 } 1535 I->second = PrevLabel; 1536} 1537 1538// Each LexicalScope has first instruction and last instruction to mark 1539// beginning and end of a scope respectively. Create an inverse map that list 1540// scopes starts (and ends) with an instruction. One instruction may start (or 1541// end) multiple scopes. Ignore scopes that are not reachable. 1542void DwarfDebug::identifyScopeMarkers() { 1543 SmallVector<LexicalScope *, 4> WorkList; 1544 WorkList.push_back(LScopes.getCurrentFunctionScope()); 1545 while (!WorkList.empty()) { 1546 LexicalScope *S = WorkList.pop_back_val(); 1547 1548 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren(); 1549 if (!Children.empty()) 1550 for (SmallVectorImpl<LexicalScope *>::const_iterator SI = Children.begin(), 1551 SE = Children.end(); SI != SE; ++SI) 1552 WorkList.push_back(*SI); 1553 1554 if (S->isAbstractScope()) 1555 continue; 1556 1557 const SmallVectorImpl<InsnRange> &Ranges = S->getRanges(); 1558 if (Ranges.empty()) 1559 continue; 1560 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 1561 RE = Ranges.end(); RI != RE; ++RI) { 1562 assert(RI->first && "InsnRange does not have first instruction!"); 1563 assert(RI->second && "InsnRange does not have second instruction!"); 1564 requestLabelBeforeInsn(RI->first); 1565 requestLabelAfterInsn(RI->second); 1566 } 1567 } 1568} 1569 1570// Get MDNode for DebugLoc's scope. 1571static MDNode *getScopeNode(DebugLoc DL, const LLVMContext &Ctx) { 1572 if (MDNode *InlinedAt = DL.getInlinedAt(Ctx)) 1573 return getScopeNode(DebugLoc::getFromDILocation(InlinedAt), Ctx); 1574 return DL.getScope(Ctx); 1575} 1576 1577// Walk up the scope chain of given debug loc and find line number info 1578// for the function. 1579static DebugLoc getFnDebugLoc(DebugLoc DL, const LLVMContext &Ctx) { 1580 const MDNode *Scope = getScopeNode(DL, Ctx); 1581 DISubprogram SP = getDISubprogram(Scope); 1582 if (SP.isSubprogram()) { 1583 // Check for number of operands since the compatibility is 1584 // cheap here. 1585 if (SP->getNumOperands() > 19) 1586 return DebugLoc::get(SP.getScopeLineNumber(), 0, SP); 1587 else 1588 return DebugLoc::get(SP.getLineNumber(), 0, SP); 1589 } 1590 1591 return DebugLoc(); 1592} 1593 1594// Gather pre-function debug information. Assumes being called immediately 1595// after the function entry point has been emitted. 1596void DwarfDebug::beginFunction(const MachineFunction *MF) { 1597 if (!MMI->hasDebugInfo()) return; 1598 LScopes.initialize(*MF); 1599 if (LScopes.empty()) return; 1600 identifyScopeMarkers(); 1601 1602 // Set DwarfCompileUnitID in MCContext to the Compile Unit this function 1603 // belongs to. 1604 LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); 1605 CompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode()); 1606 assert(TheCU && "Unable to find compile unit!"); 1607 if (Asm->TM.hasMCUseLoc() && Asm->OutStreamer.hasRawTextSupport()) 1608 // Use a single line table if we are using .loc and generating assembly. 1609 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0); 1610 else 1611 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID()); 1612 1613 FunctionBeginSym = Asm->GetTempSymbol("func_begin", 1614 Asm->getFunctionNumber()); 1615 // Assumes in correct section after the entry point. 1616 Asm->OutStreamer.EmitLabel(FunctionBeginSym); 1617 1618 assert(UserVariables.empty() && DbgValues.empty() && "Maps weren't cleaned"); 1619 1620 const TargetRegisterInfo *TRI = Asm->TM.getRegisterInfo(); 1621 // LiveUserVar - Map physreg numbers to the MDNode they contain. 1622 std::vector<const MDNode*> LiveUserVar(TRI->getNumRegs()); 1623 1624 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end(); 1625 I != E; ++I) { 1626 bool AtBlockEntry = true; 1627 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end(); 1628 II != IE; ++II) { 1629 const MachineInstr *MI = II; 1630 1631 if (MI->isDebugValue()) { 1632 assert(MI->getNumOperands() > 1 && "Invalid machine instruction!"); 1633 1634 // Keep track of user variables. 1635 const MDNode *Var = 1636 MI->getOperand(MI->getNumOperands() - 1).getMetadata(); 1637 1638 // Variable is in a register, we need to check for clobbers. 1639 if (isDbgValueInDefinedReg(MI)) 1640 LiveUserVar[MI->getOperand(0).getReg()] = Var; 1641 1642 // Check the history of this variable. 1643 SmallVectorImpl<const MachineInstr*> &History = DbgValues[Var]; 1644 if (History.empty()) { 1645 UserVariables.push_back(Var); 1646 // The first mention of a function argument gets the FunctionBeginSym 1647 // label, so arguments are visible when breaking at function entry. 1648 DIVariable DV(Var); 1649 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable && 1650 DISubprogram(getDISubprogram(DV.getContext())) 1651 .describes(MF->getFunction())) 1652 LabelsBeforeInsn[MI] = FunctionBeginSym; 1653 } else { 1654 // We have seen this variable before. Try to coalesce DBG_VALUEs. 1655 const MachineInstr *Prev = History.back(); 1656 if (Prev->isDebugValue()) { 1657 // Coalesce identical entries at the end of History. 1658 if (History.size() >= 2 && 1659 Prev->isIdenticalTo(History[History.size() - 2])) { 1660 DEBUG(dbgs() << "Coalescing identical DBG_VALUE entries:\n" 1661 << "\t" << *Prev 1662 << "\t" << *History[History.size() - 2] << "\n"); 1663 History.pop_back(); 1664 } 1665 1666 // Terminate old register assignments that don't reach MI; 1667 MachineFunction::const_iterator PrevMBB = Prev->getParent(); 1668 if (PrevMBB != I && (!AtBlockEntry || llvm::next(PrevMBB) != I) && 1669 isDbgValueInDefinedReg(Prev)) { 1670 // Previous register assignment needs to terminate at the end of 1671 // its basic block. 1672 MachineBasicBlock::const_iterator LastMI = 1673 PrevMBB->getLastNonDebugInstr(); 1674 if (LastMI == PrevMBB->end()) { 1675 // Drop DBG_VALUE for empty range. 1676 DEBUG(dbgs() << "Dropping DBG_VALUE for empty range:\n" 1677 << "\t" << *Prev << "\n"); 1678 History.pop_back(); 1679 } else if (llvm::next(PrevMBB) != PrevMBB->getParent()->end()) 1680 // Terminate after LastMI. 1681 History.push_back(LastMI); 1682 } 1683 } 1684 } 1685 History.push_back(MI); 1686 } else { 1687 // Not a DBG_VALUE instruction. 1688 if (!MI->isLabel()) 1689 AtBlockEntry = false; 1690 1691 // First known non-DBG_VALUE and non-frame setup location marks 1692 // the beginning of the function body. 1693 if (!MI->getFlag(MachineInstr::FrameSetup) && 1694 (PrologEndLoc.isUnknown() && !MI->getDebugLoc().isUnknown())) 1695 PrologEndLoc = MI->getDebugLoc(); 1696 1697 // Check if the instruction clobbers any registers with debug vars. 1698 for (MachineInstr::const_mop_iterator MOI = MI->operands_begin(), 1699 MOE = MI->operands_end(); MOI != MOE; ++MOI) { 1700 if (!MOI->isReg() || !MOI->isDef() || !MOI->getReg()) 1701 continue; 1702 for (MCRegAliasIterator AI(MOI->getReg(), TRI, true); 1703 AI.isValid(); ++AI) { 1704 unsigned Reg = *AI; 1705 const MDNode *Var = LiveUserVar[Reg]; 1706 if (!Var) 1707 continue; 1708 // Reg is now clobbered. 1709 LiveUserVar[Reg] = 0; 1710 1711 // Was MD last defined by a DBG_VALUE referring to Reg? 1712 DbgValueHistoryMap::iterator HistI = DbgValues.find(Var); 1713 if (HistI == DbgValues.end()) 1714 continue; 1715 SmallVectorImpl<const MachineInstr*> &History = HistI->second; 1716 if (History.empty()) 1717 continue; 1718 const MachineInstr *Prev = History.back(); 1719 // Sanity-check: Register assignments are terminated at the end of 1720 // their block. 1721 if (!Prev->isDebugValue() || Prev->getParent() != MI->getParent()) 1722 continue; 1723 // Is the variable still in Reg? 1724 if (!isDbgValueInDefinedReg(Prev) || 1725 Prev->getOperand(0).getReg() != Reg) 1726 continue; 1727 // Var is clobbered. Make sure the next instruction gets a label. 1728 History.push_back(MI); 1729 } 1730 } 1731 } 1732 } 1733 } 1734 1735 for (DbgValueHistoryMap::iterator I = DbgValues.begin(), E = DbgValues.end(); 1736 I != E; ++I) { 1737 SmallVectorImpl<const MachineInstr*> &History = I->second; 1738 if (History.empty()) 1739 continue; 1740 1741 // Make sure the final register assignments are terminated. 1742 const MachineInstr *Prev = History.back(); 1743 if (Prev->isDebugValue() && isDbgValueInDefinedReg(Prev)) { 1744 const MachineBasicBlock *PrevMBB = Prev->getParent(); 1745 MachineBasicBlock::const_iterator LastMI = 1746 PrevMBB->getLastNonDebugInstr(); 1747 if (LastMI == PrevMBB->end()) 1748 // Drop DBG_VALUE for empty range. 1749 History.pop_back(); 1750 else if (PrevMBB != &PrevMBB->getParent()->back()) { 1751 // Terminate after LastMI. 1752 History.push_back(LastMI); 1753 } 1754 } 1755 // Request labels for the full history. 1756 for (unsigned i = 0, e = History.size(); i != e; ++i) { 1757 const MachineInstr *MI = History[i]; 1758 if (MI->isDebugValue()) 1759 requestLabelBeforeInsn(MI); 1760 else 1761 requestLabelAfterInsn(MI); 1762 } 1763 } 1764 1765 PrevInstLoc = DebugLoc(); 1766 PrevLabel = FunctionBeginSym; 1767 1768 // Record beginning of function. 1769 if (!PrologEndLoc.isUnknown()) { 1770 DebugLoc FnStartDL = getFnDebugLoc(PrologEndLoc, 1771 MF->getFunction()->getContext()); 1772 recordSourceLine(FnStartDL.getLine(), FnStartDL.getCol(), 1773 FnStartDL.getScope(MF->getFunction()->getContext()), 1774 // We'd like to list the prologue as "not statements" but GDB behaves 1775 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing. 1776 DWARF2_FLAG_IS_STMT); 1777 } 1778} 1779 1780void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) { 1781 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS]; 1782 DIVariable DV = Var->getVariable(); 1783 // Variables with positive arg numbers are parameters. 1784 if (unsigned ArgNum = DV.getArgNumber()) { 1785 // Keep all parameters in order at the start of the variable list to ensure 1786 // function types are correct (no out-of-order parameters) 1787 // 1788 // This could be improved by only doing it for optimized builds (unoptimized 1789 // builds have the right order to begin with), searching from the back (this 1790 // would catch the unoptimized case quickly), or doing a binary search 1791 // rather than linear search. 1792 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin(); 1793 while (I != Vars.end()) { 1794 unsigned CurNum = (*I)->getVariable().getArgNumber(); 1795 // A local (non-parameter) variable has been found, insert immediately 1796 // before it. 1797 if (CurNum == 0) 1798 break; 1799 // A later indexed parameter has been found, insert immediately before it. 1800 if (CurNum > ArgNum) 1801 break; 1802 ++I; 1803 } 1804 Vars.insert(I, Var); 1805 return; 1806 } 1807 1808 Vars.push_back(Var); 1809} 1810 1811// Gather and emit post-function debug information. 1812void DwarfDebug::endFunction(const MachineFunction *MF) { 1813 if (!MMI->hasDebugInfo() || LScopes.empty()) return; 1814 1815 // Define end label for subprogram. 1816 FunctionEndSym = Asm->GetTempSymbol("func_end", 1817 Asm->getFunctionNumber()); 1818 // Assumes in correct section after the entry point. 1819 Asm->OutStreamer.EmitLabel(FunctionEndSym); 1820 // Set DwarfCompileUnitID in MCContext to default value. 1821 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0); 1822 1823 SmallPtrSet<const MDNode *, 16> ProcessedVars; 1824 collectVariableInfo(MF, ProcessedVars); 1825 1826 LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); 1827 CompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode()); 1828 assert(TheCU && "Unable to find compile unit!"); 1829 1830 // Construct abstract scopes. 1831 ArrayRef<LexicalScope *> AList = LScopes.getAbstractScopesList(); 1832 for (unsigned i = 0, e = AList.size(); i != e; ++i) { 1833 LexicalScope *AScope = AList[i]; 1834 DISubprogram SP(AScope->getScopeNode()); 1835 if (SP.isSubprogram()) { 1836 // Collect info for variables that were optimized out. 1837 DIArray Variables = SP.getVariables(); 1838 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) { 1839 DIVariable DV(Variables.getElement(i)); 1840 if (!DV || !DV.isVariable() || !ProcessedVars.insert(DV)) 1841 continue; 1842 // Check that DbgVariable for DV wasn't created earlier, when 1843 // findAbstractVariable() was called for inlined instance of DV. 1844 LLVMContext &Ctx = DV->getContext(); 1845 DIVariable CleanDV = cleanseInlinedVariable(DV, Ctx); 1846 if (AbstractVariables.lookup(CleanDV)) 1847 continue; 1848 if (LexicalScope *Scope = LScopes.findAbstractScope(DV.getContext())) 1849 addScopeVariable(Scope, new DbgVariable(DV, NULL, this)); 1850 } 1851 } 1852 if (ProcessedSPNodes.count(AScope->getScopeNode()) == 0) 1853 constructScopeDIE(TheCU, AScope); 1854 } 1855 1856 DIE *CurFnDIE = constructScopeDIE(TheCU, FnScope); 1857 1858 if (!MF->getTarget().Options.DisableFramePointerElim(*MF)) 1859 TheCU->addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr); 1860 1861 // Clear debug info 1862 for (ScopeVariablesMap::iterator 1863 I = ScopeVariables.begin(), E = ScopeVariables.end(); I != E; ++I) 1864 DeleteContainerPointers(I->second); 1865 ScopeVariables.clear(); 1866 DeleteContainerPointers(CurrentFnArguments); 1867 UserVariables.clear(); 1868 DbgValues.clear(); 1869 AbstractVariables.clear(); 1870 LabelsBeforeInsn.clear(); 1871 LabelsAfterInsn.clear(); 1872 PrevLabel = NULL; 1873} 1874 1875// Register a source line with debug info. Returns the unique label that was 1876// emitted and which provides correspondence to the source line list. 1877void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S, 1878 unsigned Flags) { 1879 StringRef Fn; 1880 StringRef Dir; 1881 unsigned Src = 1; 1882 if (S) { 1883 DIDescriptor Scope(S); 1884 1885 if (Scope.isCompileUnit()) { 1886 DICompileUnit CU(S); 1887 Fn = CU.getFilename(); 1888 Dir = CU.getDirectory(); 1889 } else if (Scope.isFile()) { 1890 DIFile F(S); 1891 Fn = F.getFilename(); 1892 Dir = F.getDirectory(); 1893 } else if (Scope.isSubprogram()) { 1894 DISubprogram SP(S); 1895 Fn = SP.getFilename(); 1896 Dir = SP.getDirectory(); 1897 } else if (Scope.isLexicalBlockFile()) { 1898 DILexicalBlockFile DBF(S); 1899 Fn = DBF.getFilename(); 1900 Dir = DBF.getDirectory(); 1901 } else if (Scope.isLexicalBlock()) { 1902 DILexicalBlock DB(S); 1903 Fn = DB.getFilename(); 1904 Dir = DB.getDirectory(); 1905 } else 1906 llvm_unreachable("Unexpected scope info"); 1907 1908 Src = getOrCreateSourceID(Fn, Dir, 1909 Asm->OutStreamer.getContext().getDwarfCompileUnitID()); 1910 } 1911 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0, 0, Fn); 1912} 1913 1914//===----------------------------------------------------------------------===// 1915// Emit Methods 1916//===----------------------------------------------------------------------===// 1917 1918// Compute the size and offset of a DIE. 1919unsigned 1920DwarfUnits::computeSizeAndOffset(DIE *Die, unsigned Offset) { 1921 // Get the children. 1922 const std::vector<DIE *> &Children = Die->getChildren(); 1923 1924 // Record the abbreviation. 1925 assignAbbrevNumber(Die->getAbbrev()); 1926 1927 // Get the abbreviation for this DIE. 1928 unsigned AbbrevNumber = Die->getAbbrevNumber(); 1929 const DIEAbbrev *Abbrev = Abbreviations->at(AbbrevNumber - 1); 1930 1931 // Set DIE offset 1932 Die->setOffset(Offset); 1933 1934 // Start the size with the size of abbreviation code. 1935 Offset += MCAsmInfo::getULEB128Size(AbbrevNumber); 1936 1937 const SmallVectorImpl<DIEValue*> &Values = Die->getValues(); 1938 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev->getData(); 1939 1940 // Size the DIE attribute values. 1941 for (unsigned i = 0, N = Values.size(); i < N; ++i) 1942 // Size attribute value. 1943 Offset += Values[i]->SizeOf(Asm, AbbrevData[i].getForm()); 1944 1945 // Size the DIE children if any. 1946 if (!Children.empty()) { 1947 assert(Abbrev->getChildrenFlag() == dwarf::DW_CHILDREN_yes && 1948 "Children flag not set"); 1949 1950 for (unsigned j = 0, M = Children.size(); j < M; ++j) 1951 Offset = computeSizeAndOffset(Children[j], Offset); 1952 1953 // End of children marker. 1954 Offset += sizeof(int8_t); 1955 } 1956 1957 Die->setSize(Offset - Die->getOffset()); 1958 return Offset; 1959} 1960 1961// Compute the size and offset of all the DIEs. 1962void DwarfUnits::computeSizeAndOffsets() { 1963 // Offset from the beginning of debug info section. 1964 for (SmallVectorImpl<CompileUnit *>::iterator I = CUs.begin(), 1965 E = CUs.end(); I != E; ++I) { 1966 unsigned Offset = 1967 sizeof(int32_t) + // Length of Compilation Unit Info 1968 sizeof(int16_t) + // DWARF version number 1969 sizeof(int32_t) + // Offset Into Abbrev. Section 1970 sizeof(int8_t); // Pointer Size (in bytes) 1971 computeSizeAndOffset((*I)->getCUDie(), Offset); 1972 } 1973} 1974 1975// Emit initial Dwarf sections with a label at the start of each one. 1976void DwarfDebug::emitSectionLabels() { 1977 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); 1978 1979 // Dwarf sections base addresses. 1980 DwarfInfoSectionSym = 1981 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info"); 1982 DwarfAbbrevSectionSym = 1983 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev"); 1984 if (useSplitDwarf()) 1985 DwarfAbbrevDWOSectionSym = 1986 emitSectionSym(Asm, TLOF.getDwarfAbbrevDWOSection(), 1987 "section_abbrev_dwo"); 1988 emitSectionSym(Asm, TLOF.getDwarfARangesSection()); 1989 1990 if (const MCSection *MacroInfo = TLOF.getDwarfMacroInfoSection()) 1991 emitSectionSym(Asm, MacroInfo); 1992 1993 DwarfLineSectionSym = 1994 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line"); 1995 emitSectionSym(Asm, TLOF.getDwarfLocSection()); 1996 if (GenerateGnuPubSections) { 1997 DwarfGnuPubNamesSectionSym = 1998 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection()); 1999 DwarfGnuPubTypesSectionSym = 2000 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection()); 2001 } else if (HasDwarfPubSections) { 2002 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection()); 2003 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection()); 2004 } 2005 2006 DwarfStrSectionSym = 2007 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string"); 2008 if (useSplitDwarf()) { 2009 DwarfStrDWOSectionSym = 2010 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string"); 2011 DwarfAddrSectionSym = 2012 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec"); 2013 } 2014 DwarfDebugRangeSectionSym = emitSectionSym(Asm, TLOF.getDwarfRangesSection(), 2015 "debug_range"); 2016 2017 DwarfDebugLocSectionSym = emitSectionSym(Asm, TLOF.getDwarfLocSection(), 2018 "section_debug_loc"); 2019 2020 TextSectionSym = emitSectionSym(Asm, TLOF.getTextSection(), "text_begin"); 2021 emitSectionSym(Asm, TLOF.getDataSection()); 2022} 2023 2024// Recursively emits a debug information entry. 2025void DwarfDebug::emitDIE(DIE *Die, std::vector<DIEAbbrev *> *Abbrevs) { 2026 // Get the abbreviation for this DIE. 2027 unsigned AbbrevNumber = Die->getAbbrevNumber(); 2028 const DIEAbbrev *Abbrev = Abbrevs->at(AbbrevNumber - 1); 2029 2030 // Emit the code (index) for the abbreviation. 2031 if (Asm->isVerbose()) 2032 Asm->OutStreamer.AddComment("Abbrev [" + Twine(AbbrevNumber) + "] 0x" + 2033 Twine::utohexstr(Die->getOffset()) + ":0x" + 2034 Twine::utohexstr(Die->getSize()) + " " + 2035 dwarf::TagString(Abbrev->getTag())); 2036 Asm->EmitULEB128(AbbrevNumber); 2037 2038 const SmallVectorImpl<DIEValue*> &Values = Die->getValues(); 2039 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev->getData(); 2040 2041 // Emit the DIE attribute values. 2042 for (unsigned i = 0, N = Values.size(); i < N; ++i) { 2043 unsigned Attr = AbbrevData[i].getAttribute(); 2044 unsigned Form = AbbrevData[i].getForm(); 2045 assert(Form && "Too many attributes for DIE (check abbreviation)"); 2046 2047 if (Asm->isVerbose()) 2048 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr)); 2049 2050 switch (Attr) { 2051 case dwarf::DW_AT_abstract_origin: { 2052 DIEEntry *E = cast<DIEEntry>(Values[i]); 2053 DIE *Origin = E->getEntry(); 2054 unsigned Addr = Origin->getOffset(); 2055 Asm->EmitInt32(Addr); 2056 break; 2057 } 2058 case dwarf::DW_AT_ranges: { 2059 // DW_AT_range Value encodes offset in debug_range section. 2060 DIEInteger *V = cast<DIEInteger>(Values[i]); 2061 2062 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) { 2063 Asm->EmitLabelPlusOffset(DwarfDebugRangeSectionSym, 2064 V->getValue(), 2065 4); 2066 } else { 2067 Asm->EmitLabelOffsetDifference(DwarfDebugRangeSectionSym, 2068 V->getValue(), 2069 DwarfDebugRangeSectionSym, 2070 4); 2071 } 2072 break; 2073 } 2074 case dwarf::DW_AT_location: { 2075 if (DIELabel *L = dyn_cast<DIELabel>(Values[i])) { 2076 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2077 Asm->EmitLabelReference(L->getValue(), 4); 2078 else 2079 Asm->EmitLabelDifference(L->getValue(), DwarfDebugLocSectionSym, 4); 2080 } else { 2081 Values[i]->EmitValue(Asm, Form); 2082 } 2083 break; 2084 } 2085 case dwarf::DW_AT_accessibility: { 2086 if (Asm->isVerbose()) { 2087 DIEInteger *V = cast<DIEInteger>(Values[i]); 2088 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(V->getValue())); 2089 } 2090 Values[i]->EmitValue(Asm, Form); 2091 break; 2092 } 2093 default: 2094 // Emit an attribute using the defined form. 2095 Values[i]->EmitValue(Asm, Form); 2096 break; 2097 } 2098 } 2099 2100 // Emit the DIE children if any. 2101 if (Abbrev->getChildrenFlag() == dwarf::DW_CHILDREN_yes) { 2102 const std::vector<DIE *> &Children = Die->getChildren(); 2103 2104 for (unsigned j = 0, M = Children.size(); j < M; ++j) 2105 emitDIE(Children[j], Abbrevs); 2106 2107 if (Asm->isVerbose()) 2108 Asm->OutStreamer.AddComment("End Of Children Mark"); 2109 Asm->EmitInt8(0); 2110 } 2111} 2112 2113// Emit the various dwarf units to the unit section USection with 2114// the abbreviations going into ASection. 2115void DwarfUnits::emitUnits(DwarfDebug *DD, 2116 const MCSection *USection, 2117 const MCSection *ASection, 2118 const MCSymbol *ASectionSym) { 2119 Asm->OutStreamer.SwitchSection(USection); 2120 for (SmallVectorImpl<CompileUnit *>::iterator I = CUs.begin(), 2121 E = CUs.end(); I != E; ++I) { 2122 CompileUnit *TheCU = *I; 2123 DIE *Die = TheCU->getCUDie(); 2124 2125 // Emit the compile units header. 2126 Asm->OutStreamer 2127 .EmitLabel(Asm->GetTempSymbol(USection->getLabelBeginName(), 2128 TheCU->getUniqueID())); 2129 2130 // Emit size of content not including length itself 2131 unsigned ContentSize = Die->getSize() + 2132 sizeof(int16_t) + // DWARF version number 2133 sizeof(int32_t) + // Offset Into Abbrev. Section 2134 sizeof(int8_t); // Pointer Size (in bytes) 2135 2136 Asm->OutStreamer.AddComment("Length of Compilation Unit Info"); 2137 Asm->EmitInt32(ContentSize); 2138 Asm->OutStreamer.AddComment("DWARF version number"); 2139 Asm->EmitInt16(DD->getDwarfVersion()); 2140 Asm->OutStreamer.AddComment("Offset Into Abbrev. Section"); 2141 Asm->EmitSectionOffset(Asm->GetTempSymbol(ASection->getLabelBeginName()), 2142 ASectionSym); 2143 Asm->OutStreamer.AddComment("Address Size (in bytes)"); 2144 Asm->EmitInt8(Asm->getDataLayout().getPointerSize()); 2145 2146 DD->emitDIE(Die, Abbreviations); 2147 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol(USection->getLabelEndName(), 2148 TheCU->getUniqueID())); 2149 } 2150} 2151 2152// Emit the debug info section. 2153void DwarfDebug::emitDebugInfo() { 2154 DwarfUnits &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; 2155 2156 Holder.emitUnits(this, Asm->getObjFileLowering().getDwarfInfoSection(), 2157 Asm->getObjFileLowering().getDwarfAbbrevSection(), 2158 DwarfAbbrevSectionSym); 2159} 2160 2161// Emit the abbreviation section. 2162void DwarfDebug::emitAbbreviations() { 2163 if (!useSplitDwarf()) 2164 emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection(), 2165 &Abbreviations); 2166 else 2167 emitSkeletonAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection()); 2168} 2169 2170void DwarfDebug::emitAbbrevs(const MCSection *Section, 2171 std::vector<DIEAbbrev *> *Abbrevs) { 2172 // Check to see if it is worth the effort. 2173 if (!Abbrevs->empty()) { 2174 // Start the debug abbrev section. 2175 Asm->OutStreamer.SwitchSection(Section); 2176 2177 MCSymbol *Begin = Asm->GetTempSymbol(Section->getLabelBeginName()); 2178 Asm->OutStreamer.EmitLabel(Begin); 2179 2180 // For each abbrevation. 2181 for (unsigned i = 0, N = Abbrevs->size(); i < N; ++i) { 2182 // Get abbreviation data 2183 const DIEAbbrev *Abbrev = Abbrevs->at(i); 2184 2185 // Emit the abbrevations code (base 1 index.) 2186 Asm->EmitULEB128(Abbrev->getNumber(), "Abbreviation Code"); 2187 2188 // Emit the abbreviations data. 2189 Abbrev->Emit(Asm); 2190 } 2191 2192 // Mark end of abbreviations. 2193 Asm->EmitULEB128(0, "EOM(3)"); 2194 2195 MCSymbol *End = Asm->GetTempSymbol(Section->getLabelEndName()); 2196 Asm->OutStreamer.EmitLabel(End); 2197 } 2198} 2199 2200// Emit the last address of the section and the end of the line matrix. 2201void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) { 2202 // Define last address of section. 2203 Asm->OutStreamer.AddComment("Extended Op"); 2204 Asm->EmitInt8(0); 2205 2206 Asm->OutStreamer.AddComment("Op size"); 2207 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1); 2208 Asm->OutStreamer.AddComment("DW_LNE_set_address"); 2209 Asm->EmitInt8(dwarf::DW_LNE_set_address); 2210 2211 Asm->OutStreamer.AddComment("Section end label"); 2212 2213 Asm->OutStreamer.EmitSymbolValue(Asm->GetTempSymbol("section_end",SectionEnd), 2214 Asm->getDataLayout().getPointerSize()); 2215 2216 // Mark end of matrix. 2217 Asm->OutStreamer.AddComment("DW_LNE_end_sequence"); 2218 Asm->EmitInt8(0); 2219 Asm->EmitInt8(1); 2220 Asm->EmitInt8(1); 2221} 2222 2223// Emit visible names into a hashed accelerator table section. 2224void DwarfDebug::emitAccelNames() { 2225 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2226 dwarf::DW_FORM_data4)); 2227 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2228 E = CUMap.end(); I != E; ++I) { 2229 CompileUnit *TheCU = I->second; 2230 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelNames(); 2231 for (StringMap<std::vector<DIE*> >::const_iterator 2232 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2233 StringRef Name = GI->getKey(); 2234 const std::vector<DIE *> &Entities = GI->second; 2235 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2236 DE = Entities.end(); DI != DE; ++DI) 2237 AT.AddName(Name, (*DI)); 2238 } 2239 } 2240 2241 AT.FinalizeTable(Asm, "Names"); 2242 Asm->OutStreamer.SwitchSection( 2243 Asm->getObjFileLowering().getDwarfAccelNamesSection()); 2244 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin"); 2245 Asm->OutStreamer.EmitLabel(SectionBegin); 2246 2247 // Emit the full data. 2248 AT.Emit(Asm, SectionBegin, &InfoHolder); 2249} 2250 2251// Emit objective C classes and categories into a hashed accelerator table 2252// section. 2253void DwarfDebug::emitAccelObjC() { 2254 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2255 dwarf::DW_FORM_data4)); 2256 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2257 E = CUMap.end(); I != E; ++I) { 2258 CompileUnit *TheCU = I->second; 2259 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelObjC(); 2260 for (StringMap<std::vector<DIE*> >::const_iterator 2261 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2262 StringRef Name = GI->getKey(); 2263 const std::vector<DIE *> &Entities = GI->second; 2264 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2265 DE = Entities.end(); DI != DE; ++DI) 2266 AT.AddName(Name, (*DI)); 2267 } 2268 } 2269 2270 AT.FinalizeTable(Asm, "ObjC"); 2271 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2272 .getDwarfAccelObjCSection()); 2273 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin"); 2274 Asm->OutStreamer.EmitLabel(SectionBegin); 2275 2276 // Emit the full data. 2277 AT.Emit(Asm, SectionBegin, &InfoHolder); 2278} 2279 2280// Emit namespace dies into a hashed accelerator table. 2281void DwarfDebug::emitAccelNamespaces() { 2282 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2283 dwarf::DW_FORM_data4)); 2284 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2285 E = CUMap.end(); I != E; ++I) { 2286 CompileUnit *TheCU = I->second; 2287 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelNamespace(); 2288 for (StringMap<std::vector<DIE*> >::const_iterator 2289 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2290 StringRef Name = GI->getKey(); 2291 const std::vector<DIE *> &Entities = GI->second; 2292 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2293 DE = Entities.end(); DI != DE; ++DI) 2294 AT.AddName(Name, (*DI)); 2295 } 2296 } 2297 2298 AT.FinalizeTable(Asm, "namespac"); 2299 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2300 .getDwarfAccelNamespaceSection()); 2301 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin"); 2302 Asm->OutStreamer.EmitLabel(SectionBegin); 2303 2304 // Emit the full data. 2305 AT.Emit(Asm, SectionBegin, &InfoHolder); 2306} 2307 2308// Emit type dies into a hashed accelerator table. 2309void DwarfDebug::emitAccelTypes() { 2310 std::vector<DwarfAccelTable::Atom> Atoms; 2311 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2312 dwarf::DW_FORM_data4)); 2313 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, 2314 dwarf::DW_FORM_data2)); 2315 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, 2316 dwarf::DW_FORM_data1)); 2317 DwarfAccelTable AT(Atoms); 2318 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2319 E = CUMap.end(); I != E; ++I) { 2320 CompileUnit *TheCU = I->second; 2321 const StringMap<std::vector<std::pair<DIE*, unsigned > > > &Names 2322 = TheCU->getAccelTypes(); 2323 for (StringMap<std::vector<std::pair<DIE*, unsigned> > >::const_iterator 2324 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2325 StringRef Name = GI->getKey(); 2326 const std::vector<std::pair<DIE *, unsigned> > &Entities = GI->second; 2327 for (std::vector<std::pair<DIE *, unsigned> >::const_iterator DI 2328 = Entities.begin(), DE = Entities.end(); DI !=DE; ++DI) 2329 AT.AddName(Name, (*DI).first, (*DI).second); 2330 } 2331 } 2332 2333 AT.FinalizeTable(Asm, "types"); 2334 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2335 .getDwarfAccelTypesSection()); 2336 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin"); 2337 Asm->OutStreamer.EmitLabel(SectionBegin); 2338 2339 // Emit the full data. 2340 AT.Emit(Asm, SectionBegin, &InfoHolder); 2341} 2342 2343// Public name handling. 2344// The format for the various pubnames: 2345// 2346// dwarf pubnames - offset/name pairs where the offset is the offset into the CU 2347// for the DIE that is named. 2348// 2349// gnu pubnames - offset/index value/name tuples where the offset is the offset 2350// into the CU and the index value is computed according to the type of value 2351// for the DIE that is named. 2352// 2353// For type units the offset is the offset of the skeleton DIE. For split dwarf 2354// it's the offset within the debug_info/debug_types dwo section, however, the 2355// reference in the pubname header doesn't change. 2356 2357/// computeIndexValue - Compute the gdb index value for the DIE and CU. 2358static dwarf::PubIndexEntryDescriptor computeIndexValue(CompileUnit *CU, 2359 DIE *Die) { 2360 dwarf::GDBIndexEntryLinkage Linkage = 2361 Die->findAttribute(dwarf::DW_AT_external) ? dwarf::GIEL_EXTERNAL 2362 : dwarf::GIEL_STATIC; 2363 2364 switch (Die->getTag()) { 2365 case dwarf::DW_TAG_class_type: 2366 case dwarf::DW_TAG_structure_type: 2367 case dwarf::DW_TAG_union_type: 2368 case dwarf::DW_TAG_enumeration_type: 2369 return dwarf::PubIndexEntryDescriptor( 2370 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus 2371 ? dwarf::GIEL_STATIC 2372 : dwarf::GIEL_EXTERNAL); 2373 case dwarf::DW_TAG_typedef: 2374 case dwarf::DW_TAG_base_type: 2375 case dwarf::DW_TAG_subrange_type: 2376 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC); 2377 case dwarf::DW_TAG_namespace: 2378 return dwarf::GIEK_TYPE; 2379 case dwarf::DW_TAG_subprogram: 2380 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage); 2381 case dwarf::DW_TAG_constant: 2382 case dwarf::DW_TAG_variable: 2383 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage); 2384 case dwarf::DW_TAG_enumerator: 2385 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, 2386 dwarf::GIEL_STATIC); 2387 default: 2388 return dwarf::GIEK_NONE; 2389 } 2390} 2391 2392/// emitDebugPubNames - Emit visible names into a debug pubnames section. 2393/// 2394void DwarfDebug::emitDebugPubNames(bool GnuStyle) { 2395 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2396 const MCSection *PSec = 2397 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection() 2398 : Asm->getObjFileLowering().getDwarfPubNamesSection(); 2399 2400 typedef DenseMap<const MDNode*, CompileUnit*> CUMapType; 2401 for (CUMapType::iterator I = CUMap.begin(), E = CUMap.end(); I != E; ++I) { 2402 CompileUnit *TheCU = I->second; 2403 unsigned ID = TheCU->getUniqueID(); 2404 2405 // Start the dwarf pubnames section. 2406 Asm->OutStreamer.SwitchSection(PSec); 2407 2408 // Emit a label so we can reference the beginning of this pubname section. 2409 if (GnuStyle) 2410 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("gnu_pubnames", 2411 TheCU->getUniqueID())); 2412 2413 // Emit the header. 2414 Asm->OutStreamer.AddComment("Length of Public Names Info"); 2415 Asm->EmitLabelDifference(Asm->GetTempSymbol("pubnames_end", ID), 2416 Asm->GetTempSymbol("pubnames_begin", ID), 4); 2417 2418 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("pubnames_begin", ID)); 2419 2420 Asm->OutStreamer.AddComment("DWARF Version"); 2421 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION); 2422 2423 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info"); 2424 Asm->EmitSectionOffset(Asm->GetTempSymbol(ISec->getLabelBeginName(), ID), 2425 DwarfInfoSectionSym); 2426 2427 Asm->OutStreamer.AddComment("Compilation Unit Length"); 2428 Asm->EmitLabelDifference(Asm->GetTempSymbol(ISec->getLabelEndName(), ID), 2429 Asm->GetTempSymbol(ISec->getLabelBeginName(), ID), 2430 4); 2431 2432 // Emit the pubnames for this compilation unit. 2433 const StringMap<DIE*> &Globals = TheCU->getGlobalNames(); 2434 for (StringMap<DIE*>::const_iterator 2435 GI = Globals.begin(), GE = Globals.end(); GI != GE; ++GI) { 2436 const char *Name = GI->getKeyData(); 2437 DIE *Entity = GI->second; 2438 2439 Asm->OutStreamer.AddComment("DIE offset"); 2440 Asm->EmitInt32(Entity->getOffset()); 2441 2442 if (GnuStyle) { 2443 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheCU, Entity); 2444 Asm->OutStreamer.AddComment( 2445 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " + 2446 dwarf::GDBIndexEntryLinkageString(Desc.Linkage)); 2447 Asm->EmitInt8(Desc.toBits()); 2448 } 2449 2450 if (Asm->isVerbose()) 2451 Asm->OutStreamer.AddComment("External Name"); 2452 Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength()+1)); 2453 } 2454 2455 Asm->OutStreamer.AddComment("End Mark"); 2456 Asm->EmitInt32(0); 2457 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("pubnames_end", ID)); 2458 } 2459} 2460 2461void DwarfDebug::emitDebugPubTypes(bool GnuStyle) { 2462 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2463 const MCSection *PSec = 2464 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection() 2465 : Asm->getObjFileLowering().getDwarfPubTypesSection(); 2466 2467 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2468 E = CUMap.end(); 2469 I != E; ++I) { 2470 CompileUnit *TheCU = I->second; 2471 // Start the dwarf pubtypes section. 2472 Asm->OutStreamer.SwitchSection(PSec); 2473 2474 // Emit a label so we can reference the beginning of this pubtype section. 2475 if (GnuStyle) 2476 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("gnu_pubtypes", 2477 TheCU->getUniqueID())); 2478 2479 // Emit the header. 2480 Asm->OutStreamer.AddComment("Length of Public Types Info"); 2481 Asm->EmitLabelDifference( 2482 Asm->GetTempSymbol("pubtypes_end", TheCU->getUniqueID()), 2483 Asm->GetTempSymbol("pubtypes_begin", TheCU->getUniqueID()), 4); 2484 2485 Asm->OutStreamer.EmitLabel( 2486 Asm->GetTempSymbol("pubtypes_begin", TheCU->getUniqueID())); 2487 2488 if (Asm->isVerbose()) 2489 Asm->OutStreamer.AddComment("DWARF Version"); 2490 Asm->EmitInt16(dwarf::DW_PUBTYPES_VERSION); 2491 2492 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info"); 2493 Asm->EmitSectionOffset( 2494 Asm->GetTempSymbol(ISec->getLabelBeginName(), TheCU->getUniqueID()), 2495 DwarfInfoSectionSym); 2496 2497 Asm->OutStreamer.AddComment("Compilation Unit Length"); 2498 Asm->EmitLabelDifference( 2499 Asm->GetTempSymbol(ISec->getLabelEndName(), TheCU->getUniqueID()), 2500 Asm->GetTempSymbol(ISec->getLabelBeginName(), TheCU->getUniqueID()), 4); 2501 2502 // Emit the pubtypes. 2503 const StringMap<DIE *> &Globals = TheCU->getGlobalTypes(); 2504 for (StringMap<DIE *>::const_iterator GI = Globals.begin(), 2505 GE = Globals.end(); 2506 GI != GE; ++GI) { 2507 const char *Name = GI->getKeyData(); 2508 DIE *Entity = GI->second; 2509 2510 if (Asm->isVerbose()) 2511 Asm->OutStreamer.AddComment("DIE offset"); 2512 Asm->EmitInt32(Entity->getOffset()); 2513 2514 if (GnuStyle) { 2515 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheCU, Entity); 2516 Asm->OutStreamer.AddComment( 2517 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " + 2518 dwarf::GDBIndexEntryLinkageString(Desc.Linkage)); 2519 Asm->EmitInt8(Desc.toBits()); 2520 } 2521 2522 if (Asm->isVerbose()) 2523 Asm->OutStreamer.AddComment("External Name"); 2524 2525 // Emit the name with a terminating null byte. 2526 Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength() + 1)); 2527 } 2528 2529 Asm->OutStreamer.AddComment("End Mark"); 2530 Asm->EmitInt32(0); 2531 Asm->OutStreamer.EmitLabel( 2532 Asm->GetTempSymbol("pubtypes_end", TheCU->getUniqueID())); 2533 } 2534} 2535 2536// Emit strings into a string section. 2537void DwarfUnits::emitStrings(const MCSection *StrSection, 2538 const MCSection *OffsetSection = NULL, 2539 const MCSymbol *StrSecSym = NULL) { 2540 2541 if (StringPool.empty()) return; 2542 2543 // Start the dwarf str section. 2544 Asm->OutStreamer.SwitchSection(StrSection); 2545 2546 // Get all of the string pool entries and put them in an array by their ID so 2547 // we can sort them. 2548 SmallVector<std::pair<unsigned, 2549 StringMapEntry<std::pair<MCSymbol*, unsigned> >*>, 64> Entries; 2550 2551 for (StringMap<std::pair<MCSymbol*, unsigned> >::iterator 2552 I = StringPool.begin(), E = StringPool.end(); 2553 I != E; ++I) 2554 Entries.push_back(std::make_pair(I->second.second, &*I)); 2555 2556 array_pod_sort(Entries.begin(), Entries.end()); 2557 2558 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2559 // Emit a label for reference from debug information entries. 2560 Asm->OutStreamer.EmitLabel(Entries[i].second->getValue().first); 2561 2562 // Emit the string itself with a terminating null byte. 2563 Asm->OutStreamer.EmitBytes(StringRef(Entries[i].second->getKeyData(), 2564 Entries[i].second->getKeyLength()+1)); 2565 } 2566 2567 // If we've got an offset section go ahead and emit that now as well. 2568 if (OffsetSection) { 2569 Asm->OutStreamer.SwitchSection(OffsetSection); 2570 unsigned offset = 0; 2571 unsigned size = 4; // FIXME: DWARF64 is 8. 2572 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2573 Asm->OutStreamer.EmitIntValue(offset, size); 2574 offset += Entries[i].second->getKeyLength() + 1; 2575 } 2576 } 2577} 2578 2579// Emit strings into a string section. 2580void DwarfUnits::emitAddresses(const MCSection *AddrSection) { 2581 2582 if (AddressPool.empty()) return; 2583 2584 // Start the dwarf addr section. 2585 Asm->OutStreamer.SwitchSection(AddrSection); 2586 2587 // Order the address pool entries by ID 2588 SmallVector<const MCExpr *, 64> Entries(AddressPool.size()); 2589 2590 for (DenseMap<const MCExpr *, unsigned>::iterator I = AddressPool.begin(), 2591 E = AddressPool.end(); 2592 I != E; ++I) 2593 Entries[I->second] = I->first; 2594 2595 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2596 // Emit an expression for reference from debug information entries. 2597 if (const MCExpr *Expr = Entries[i]) 2598 Asm->OutStreamer.EmitValue(Expr, Asm->getDataLayout().getPointerSize()); 2599 else 2600 Asm->OutStreamer.EmitIntValue(0, Asm->getDataLayout().getPointerSize()); 2601 } 2602 2603} 2604 2605// Emit visible names into a debug str section. 2606void DwarfDebug::emitDebugStr() { 2607 DwarfUnits &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; 2608 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection()); 2609} 2610 2611// Emit locations into the debug loc section. 2612void DwarfDebug::emitDebugLoc() { 2613 if (DotDebugLocEntries.empty()) 2614 return; 2615 2616 for (SmallVectorImpl<DotDebugLocEntry>::iterator 2617 I = DotDebugLocEntries.begin(), E = DotDebugLocEntries.end(); 2618 I != E; ++I) { 2619 DotDebugLocEntry &Entry = *I; 2620 if (I + 1 != DotDebugLocEntries.end()) 2621 Entry.Merge(I+1); 2622 } 2623 2624 // Start the dwarf loc section. 2625 Asm->OutStreamer.SwitchSection( 2626 Asm->getObjFileLowering().getDwarfLocSection()); 2627 unsigned char Size = Asm->getDataLayout().getPointerSize(); 2628 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", 0)); 2629 unsigned index = 1; 2630 for (SmallVectorImpl<DotDebugLocEntry>::iterator 2631 I = DotDebugLocEntries.begin(), E = DotDebugLocEntries.end(); 2632 I != E; ++I, ++index) { 2633 DotDebugLocEntry &Entry = *I; 2634 if (Entry.isMerged()) continue; 2635 if (Entry.isEmpty()) { 2636 Asm->OutStreamer.EmitIntValue(0, Size); 2637 Asm->OutStreamer.EmitIntValue(0, Size); 2638 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", index)); 2639 } else { 2640 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size); 2641 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size); 2642 DIVariable DV(Entry.getVariable()); 2643 Asm->OutStreamer.AddComment("Loc expr size"); 2644 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol(); 2645 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol(); 2646 Asm->EmitLabelDifference(end, begin, 2); 2647 Asm->OutStreamer.EmitLabel(begin); 2648 if (Entry.isInt()) { 2649 DIBasicType BTy(DV.getType()); 2650 if (BTy.Verify() && 2651 (BTy.getEncoding() == dwarf::DW_ATE_signed 2652 || BTy.getEncoding() == dwarf::DW_ATE_signed_char)) { 2653 Asm->OutStreamer.AddComment("DW_OP_consts"); 2654 Asm->EmitInt8(dwarf::DW_OP_consts); 2655 Asm->EmitSLEB128(Entry.getInt()); 2656 } else { 2657 Asm->OutStreamer.AddComment("DW_OP_constu"); 2658 Asm->EmitInt8(dwarf::DW_OP_constu); 2659 Asm->EmitULEB128(Entry.getInt()); 2660 } 2661 } else if (Entry.isLocation()) { 2662 MachineLocation Loc = Entry.getLoc(); 2663 if (!DV.hasComplexAddress()) 2664 // Regular entry. 2665 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2666 else { 2667 // Complex address entry. 2668 unsigned N = DV.getNumAddrElements(); 2669 unsigned i = 0; 2670 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) { 2671 if (Loc.getOffset()) { 2672 i = 2; 2673 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2674 Asm->OutStreamer.AddComment("DW_OP_deref"); 2675 Asm->EmitInt8(dwarf::DW_OP_deref); 2676 Asm->OutStreamer.AddComment("DW_OP_plus_uconst"); 2677 Asm->EmitInt8(dwarf::DW_OP_plus_uconst); 2678 Asm->EmitSLEB128(DV.getAddrElement(1)); 2679 } else { 2680 // If first address element is OpPlus then emit 2681 // DW_OP_breg + Offset instead of DW_OP_reg + Offset. 2682 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1)); 2683 Asm->EmitDwarfRegOp(TLoc, DV.isIndirect()); 2684 i = 2; 2685 } 2686 } else { 2687 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2688 } 2689 2690 // Emit remaining complex address elements. 2691 for (; i < N; ++i) { 2692 uint64_t Element = DV.getAddrElement(i); 2693 if (Element == DIBuilder::OpPlus) { 2694 Asm->EmitInt8(dwarf::DW_OP_plus_uconst); 2695 Asm->EmitULEB128(DV.getAddrElement(++i)); 2696 } else if (Element == DIBuilder::OpDeref) { 2697 if (!Loc.isReg()) 2698 Asm->EmitInt8(dwarf::DW_OP_deref); 2699 } else 2700 llvm_unreachable("unknown Opcode found in complex address"); 2701 } 2702 } 2703 } 2704 // else ... ignore constant fp. There is not any good way to 2705 // to represent them here in dwarf. 2706 Asm->OutStreamer.EmitLabel(end); 2707 } 2708 } 2709} 2710 2711struct SymbolCUSorter { 2712 SymbolCUSorter(const MCStreamer &s) : Streamer(s) {} 2713 const MCStreamer &Streamer; 2714 2715 bool operator() (const SymbolCU &A, const SymbolCU &B) { 2716 unsigned IA = A.Sym ? Streamer.GetSymbolOrder(A.Sym) : 0; 2717 unsigned IB = B.Sym ? Streamer.GetSymbolOrder(B.Sym) : 0; 2718 2719 // Symbols with no order assigned should be placed at the end. 2720 // (e.g. section end labels) 2721 if (IA == 0) 2722 IA = (unsigned)(-1); 2723 if (IB == 0) 2724 IB = (unsigned)(-1); 2725 return IA < IB; 2726 } 2727}; 2728 2729static bool CUSort(const CompileUnit *A, const CompileUnit *B) { 2730 return (A->getUniqueID() < B->getUniqueID()); 2731} 2732 2733struct ArangeSpan { 2734 const MCSymbol *Start, *End; 2735}; 2736 2737// Emit a debug aranges section, containing a CU lookup for any 2738// address we can tie back to a CU. 2739void DwarfDebug::emitDebugARanges() { 2740 // Start the dwarf aranges section. 2741 Asm->OutStreamer 2742 .SwitchSection(Asm->getObjFileLowering().getDwarfARangesSection()); 2743 2744 typedef DenseMap<CompileUnit *, std::vector<ArangeSpan> > SpansType; 2745 2746 SpansType Spans; 2747 2748 // Build a list of sections used. 2749 std::vector<const MCSection *> Sections; 2750 for (SectionMapType::iterator it = SectionMap.begin(); it != SectionMap.end(); 2751 it++) { 2752 const MCSection *Section = it->first; 2753 Sections.push_back(Section); 2754 } 2755 2756 // Sort the sections into order. 2757 // This is only done to ensure consistent output order across different runs. 2758 std::sort(Sections.begin(), Sections.end(), SectionSort); 2759 2760 // Build a set of address spans, sorted by CU. 2761 for (size_t SecIdx=0;SecIdx<Sections.size();SecIdx++) { 2762 const MCSection *Section = Sections[SecIdx]; 2763 SmallVector<SymbolCU, 8> &List = SectionMap[Section]; 2764 if (List.size() < 2) 2765 continue; 2766 2767 // Sort the symbols by offset within the section. 2768 SymbolCUSorter sorter(Asm->OutStreamer); 2769 std::sort(List.begin(), List.end(), sorter); 2770 2771 // If we have no section (e.g. common), just write out 2772 // individual spans for each symbol. 2773 if (Section == NULL) { 2774 for (size_t n = 0; n < List.size(); n++) { 2775 const SymbolCU &Cur = List[n]; 2776 2777 ArangeSpan Span; 2778 Span.Start = Cur.Sym; 2779 Span.End = NULL; 2780 if (Cur.CU) 2781 Spans[Cur.CU].push_back(Span); 2782 } 2783 } else { 2784 // Build spans between each label. 2785 const MCSymbol *StartSym = List[0].Sym; 2786 for (size_t n = 1; n < List.size(); n++) { 2787 const SymbolCU &Prev = List[n - 1]; 2788 const SymbolCU &Cur = List[n]; 2789 2790 // Try and build the longest span we can within the same CU. 2791 if (Cur.CU != Prev.CU) { 2792 ArangeSpan Span; 2793 Span.Start = StartSym; 2794 Span.End = Cur.Sym; 2795 Spans[Prev.CU].push_back(Span); 2796 StartSym = Cur.Sym; 2797 } 2798 } 2799 } 2800 } 2801 2802 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2803 unsigned PtrSize = Asm->getDataLayout().getPointerSize(); 2804 2805 // Build a list of CUs used. 2806 std::vector<CompileUnit *> CUs; 2807 for (SpansType::iterator it = Spans.begin(); it != Spans.end(); it++) { 2808 CompileUnit *CU = it->first; 2809 CUs.push_back(CU); 2810 } 2811 2812 // Sort the CU list (again, to ensure consistent output order). 2813 std::sort(CUs.begin(), CUs.end(), CUSort); 2814 2815 // Emit an arange table for each CU we used. 2816 for (size_t CUIdx=0;CUIdx<CUs.size();CUIdx++) { 2817 CompileUnit *CU = CUs[CUIdx]; 2818 std::vector<ArangeSpan> &List = Spans[CU]; 2819 2820 // Emit size of content not including length itself. 2821 unsigned ContentSize 2822 = sizeof(int16_t) // DWARF ARange version number 2823 + sizeof(int32_t) // Offset of CU in the .debug_info section 2824 + sizeof(int8_t) // Pointer Size (in bytes) 2825 + sizeof(int8_t); // Segment Size (in bytes) 2826 2827 unsigned TupleSize = PtrSize * 2; 2828 2829 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple. 2830 unsigned Padding = 0; 2831 while (((sizeof(int32_t) + ContentSize + Padding) % TupleSize) != 0) 2832 Padding++; 2833 2834 ContentSize += Padding; 2835 ContentSize += (List.size() + 1) * TupleSize; 2836 2837 // For each compile unit, write the list of spans it covers. 2838 Asm->OutStreamer.AddComment("Length of ARange Set"); 2839 Asm->EmitInt32(ContentSize); 2840 Asm->OutStreamer.AddComment("DWARF Arange version number"); 2841 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION); 2842 Asm->OutStreamer.AddComment("Offset Into Debug Info Section"); 2843 Asm->EmitSectionOffset( 2844 Asm->GetTempSymbol(ISec->getLabelBeginName(), CU->getUniqueID()), 2845 DwarfInfoSectionSym); 2846 Asm->OutStreamer.AddComment("Address Size (in bytes)"); 2847 Asm->EmitInt8(PtrSize); 2848 Asm->OutStreamer.AddComment("Segment Size (in bytes)"); 2849 Asm->EmitInt8(0); 2850 2851 for (unsigned n = 0; n < Padding; n++) 2852 Asm->EmitInt8(0xff); 2853 2854 for (unsigned n = 0; n < List.size(); n++) { 2855 const ArangeSpan &Span = List[n]; 2856 Asm->EmitLabelReference(Span.Start, PtrSize); 2857 2858 // Calculate the size as being from the span start to it's end. 2859 if (Span.End) { 2860 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize); 2861 } else { 2862 // For symbols without an end marker (e.g. common), we 2863 // write a single arange entry containing just that one symbol. 2864 uint64_t Size = SymSize[Span.Start]; 2865 if (Size == 0) 2866 Size = 1; 2867 2868 Asm->OutStreamer.EmitIntValue(Size, PtrSize); 2869 } 2870 } 2871 2872 Asm->OutStreamer.AddComment("ARange terminator"); 2873 Asm->OutStreamer.EmitIntValue(0, PtrSize); 2874 Asm->OutStreamer.EmitIntValue(0, PtrSize); 2875 } 2876} 2877 2878// Emit visible names into a debug ranges section. 2879void DwarfDebug::emitDebugRanges() { 2880 // Start the dwarf ranges section. 2881 Asm->OutStreamer 2882 .SwitchSection(Asm->getObjFileLowering().getDwarfRangesSection()); 2883 unsigned char Size = Asm->getDataLayout().getPointerSize(); 2884 for (SmallVectorImpl<const MCSymbol *>::iterator 2885 I = DebugRangeSymbols.begin(), E = DebugRangeSymbols.end(); 2886 I != E; ++I) { 2887 if (*I) 2888 Asm->OutStreamer.EmitSymbolValue(const_cast<MCSymbol*>(*I), Size); 2889 else 2890 Asm->OutStreamer.EmitIntValue(0, Size); 2891 } 2892} 2893 2894// Emit visible names into a debug macinfo section. 2895void DwarfDebug::emitDebugMacInfo() { 2896 if (const MCSection *LineInfo = 2897 Asm->getObjFileLowering().getDwarfMacroInfoSection()) { 2898 // Start the dwarf macinfo section. 2899 Asm->OutStreamer.SwitchSection(LineInfo); 2900 } 2901} 2902 2903// DWARF5 Experimental Separate Dwarf emitters. 2904 2905// This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list, 2906// DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id, 2907// DW_AT_ranges_base, DW_AT_addr_base. 2908CompileUnit *DwarfDebug::constructSkeletonCU(const CompileUnit *CU) { 2909 2910 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit); 2911 CompileUnit *NewCU = new CompileUnit(CU->getUniqueID(), Die, CU->getNode(), 2912 Asm, this, &SkeletonHolder); 2913 2914 NewCU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name, 2915 DICompileUnit(CU->getNode()).getSplitDebugFilename()); 2916 2917 // Relocate to the beginning of the addr_base section, else 0 for the 2918 // beginning of the one for this compile unit. 2919 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2920 NewCU->addLabel(Die, dwarf::DW_AT_GNU_addr_base, dwarf::DW_FORM_sec_offset, 2921 DwarfAddrSectionSym); 2922 else 2923 NewCU->addUInt(Die, dwarf::DW_AT_GNU_addr_base, 2924 dwarf::DW_FORM_sec_offset, 0); 2925 2926 // 2.17.1 requires that we use DW_AT_low_pc for a single entry point 2927 // into an entity. We're using 0, or a NULL label for this. 2928 NewCU->addUInt(Die, dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr, 0); 2929 2930 // DW_AT_stmt_list is a offset of line number information for this 2931 // compile unit in debug_line section. 2932 // FIXME: Should handle multiple compile units. 2933 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2934 NewCU->addLabel(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 2935 DwarfLineSectionSym); 2936 else 2937 NewCU->addUInt(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 0); 2938 2939 if (!CompilationDir.empty()) 2940 NewCU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir); 2941 2942 // Flags to let the linker know we have emitted new style pubnames. 2943 if (GenerateGnuPubSections) { 2944 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2945 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_sec_offset, 2946 Asm->GetTempSymbol("gnu_pubnames", NewCU->getUniqueID())); 2947 else 2948 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_data4, 2949 Asm->GetTempSymbol("gnu_pubnames", NewCU->getUniqueID()), 2950 DwarfGnuPubNamesSectionSym); 2951 2952 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2953 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_sec_offset, 2954 Asm->GetTempSymbol("gnu_pubtypes", NewCU->getUniqueID())); 2955 else 2956 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_data4, 2957 Asm->GetTempSymbol("gnu_pubtypes", NewCU->getUniqueID()), 2958 DwarfGnuPubTypesSectionSym); 2959 } 2960 2961 // Flag if we've emitted any ranges and their location for the compile unit. 2962 if (DebugRangeSymbols.size()) { 2963 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2964 NewCU->addLabel(Die, dwarf::DW_AT_GNU_ranges_base, 2965 dwarf::DW_FORM_sec_offset, DwarfDebugRangeSectionSym); 2966 else 2967 NewCU->addUInt(Die, dwarf::DW_AT_GNU_ranges_base, dwarf::DW_FORM_data4, 2968 0); 2969 } 2970 2971 SkeletonHolder.addUnit(NewCU); 2972 SkeletonCUs.push_back(NewCU); 2973 2974 return NewCU; 2975} 2976 2977void DwarfDebug::emitSkeletonAbbrevs(const MCSection *Section) { 2978 assert(useSplitDwarf() && "No split dwarf debug info?"); 2979 emitAbbrevs(Section, &SkeletonAbbrevs); 2980} 2981 2982// Emit the .debug_info.dwo section for separated dwarf. This contains the 2983// compile units that would normally be in debug_info. 2984void DwarfDebug::emitDebugInfoDWO() { 2985 assert(useSplitDwarf() && "No split dwarf debug info?"); 2986 InfoHolder.emitUnits(this, Asm->getObjFileLowering().getDwarfInfoDWOSection(), 2987 Asm->getObjFileLowering().getDwarfAbbrevDWOSection(), 2988 DwarfAbbrevDWOSectionSym); 2989} 2990 2991// Emit the .debug_abbrev.dwo section for separated dwarf. This contains the 2992// abbreviations for the .debug_info.dwo section. 2993void DwarfDebug::emitDebugAbbrevDWO() { 2994 assert(useSplitDwarf() && "No split dwarf?"); 2995 emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection(), 2996 &Abbreviations); 2997} 2998 2999// Emit the .debug_str.dwo section for separated dwarf. This contains the 3000// string section and is identical in format to traditional .debug_str 3001// sections. 3002void DwarfDebug::emitDebugStrDWO() { 3003 assert(useSplitDwarf() && "No split dwarf?"); 3004 const MCSection *OffSec = Asm->getObjFileLowering() 3005 .getDwarfStrOffDWOSection(); 3006 const MCSymbol *StrSym = DwarfStrSectionSym; 3007 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(), 3008 OffSec, StrSym); 3009} 3010