DwarfDebug.cpp revision 1d36113c05e611c0fba9b872b5f03eca9848bd69
1//===-- llvm/CodeGen/DwarfDebug.cpp - Dwarf Debug Framework ---------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file contains support for writing dwarf debug info into asm files. 11// 12//===----------------------------------------------------------------------===// 13 14#define DEBUG_TYPE "dwarfdebug" 15#include "DwarfDebug.h" 16#include "DIE.h" 17#include "DIEHash.h" 18#include "DwarfAccelTable.h" 19#include "DwarfCompileUnit.h" 20#include "llvm/ADT/STLExtras.h" 21#include "llvm/ADT/Statistic.h" 22#include "llvm/ADT/StringExtras.h" 23#include "llvm/ADT/Triple.h" 24#include "llvm/CodeGen/MachineFunction.h" 25#include "llvm/CodeGen/MachineModuleInfo.h" 26#include "llvm/DIBuilder.h" 27#include "llvm/DebugInfo.h" 28#include "llvm/IR/Constants.h" 29#include "llvm/IR/DataLayout.h" 30#include "llvm/IR/Instructions.h" 31#include "llvm/IR/Module.h" 32#include "llvm/MC/MCAsmInfo.h" 33#include "llvm/MC/MCSection.h" 34#include "llvm/MC/MCStreamer.h" 35#include "llvm/MC/MCSymbol.h" 36#include "llvm/Support/CommandLine.h" 37#include "llvm/Support/Debug.h" 38#include "llvm/Support/Dwarf.h" 39#include "llvm/Support/ErrorHandling.h" 40#include "llvm/Support/FormattedStream.h" 41#include "llvm/Support/MD5.h" 42#include "llvm/Support/Path.h" 43#include "llvm/Support/Timer.h" 44#include "llvm/Support/ValueHandle.h" 45#include "llvm/Target/TargetFrameLowering.h" 46#include "llvm/Target/TargetLoweringObjectFile.h" 47#include "llvm/Target/TargetMachine.h" 48#include "llvm/Target/TargetOptions.h" 49#include "llvm/Target/TargetRegisterInfo.h" 50using namespace llvm; 51 52static cl::opt<bool> 53DisableDebugInfoPrinting("disable-debug-info-print", cl::Hidden, 54 cl::desc("Disable debug info printing")); 55 56static cl::opt<bool> UnknownLocations( 57 "use-unknown-locations", cl::Hidden, 58 cl::desc("Make an absence of debug location information explicit."), 59 cl::init(false)); 60 61static cl::opt<bool> 62GenerateODRHash("generate-odr-hash", cl::Hidden, 63 cl::desc("Add an ODR hash to external type DIEs."), 64 cl::init(false)); 65 66static cl::opt<bool> 67GenerateCUHash("generate-cu-hash", cl::Hidden, 68 cl::desc("Add the CU hash as the dwo_id."), 69 cl::init(false)); 70 71static cl::opt<bool> 72GenerateGnuPubSections("generate-gnu-dwarf-pub-sections", cl::Hidden, 73 cl::desc("Generate GNU-style pubnames and pubtypes"), 74 cl::init(false)); 75 76namespace { 77enum DefaultOnOff { 78 Default, 79 Enable, 80 Disable 81}; 82} 83 84static cl::opt<DefaultOnOff> 85DwarfAccelTables("dwarf-accel-tables", cl::Hidden, 86 cl::desc("Output prototype dwarf accelerator tables."), 87 cl::values(clEnumVal(Default, "Default for platform"), 88 clEnumVal(Enable, "Enabled"), 89 clEnumVal(Disable, "Disabled"), clEnumValEnd), 90 cl::init(Default)); 91 92static cl::opt<DefaultOnOff> 93SplitDwarf("split-dwarf", cl::Hidden, 94 cl::desc("Output prototype dwarf split debug info."), 95 cl::values(clEnumVal(Default, "Default for platform"), 96 clEnumVal(Enable, "Enabled"), 97 clEnumVal(Disable, "Disabled"), clEnumValEnd), 98 cl::init(Default)); 99 100static cl::opt<DefaultOnOff> 101DwarfPubSections("generate-dwarf-pub-sections", cl::Hidden, 102 cl::desc("Generate DWARF pubnames and pubtypes sections"), 103 cl::values(clEnumVal(Default, "Default for platform"), 104 clEnumVal(Enable, "Enabled"), 105 clEnumVal(Disable, "Disabled"), clEnumValEnd), 106 cl::init(Default)); 107 108static const char *const DWARFGroupName = "DWARF Emission"; 109static const char *const DbgTimerName = "DWARF Debug Writer"; 110 111//===----------------------------------------------------------------------===// 112 113// Configuration values for initial hash set sizes (log2). 114// 115static const unsigned InitAbbreviationsSetSize = 9; // log2(512) 116 117namespace llvm { 118 119/// resolve - Look in the DwarfDebug map for the MDNode that 120/// corresponds to the reference. 121template <typename T> 122T DbgVariable::resolve(DIRef<T> Ref) const { 123 return DD->resolve(Ref); 124} 125 126DIType DbgVariable::getType() const { 127 DIType Ty = Var.getType(); 128 // FIXME: isBlockByrefVariable should be reformulated in terms of complex 129 // addresses instead. 130 if (Var.isBlockByrefVariable()) { 131 /* Byref variables, in Blocks, are declared by the programmer as 132 "SomeType VarName;", but the compiler creates a 133 __Block_byref_x_VarName struct, and gives the variable VarName 134 either the struct, or a pointer to the struct, as its type. This 135 is necessary for various behind-the-scenes things the compiler 136 needs to do with by-reference variables in blocks. 137 138 However, as far as the original *programmer* is concerned, the 139 variable should still have type 'SomeType', as originally declared. 140 141 The following function dives into the __Block_byref_x_VarName 142 struct to find the original type of the variable. This will be 143 passed back to the code generating the type for the Debug 144 Information Entry for the variable 'VarName'. 'VarName' will then 145 have the original type 'SomeType' in its debug information. 146 147 The original type 'SomeType' will be the type of the field named 148 'VarName' inside the __Block_byref_x_VarName struct. 149 150 NOTE: In order for this to not completely fail on the debugger 151 side, the Debug Information Entry for the variable VarName needs to 152 have a DW_AT_location that tells the debugger how to unwind through 153 the pointers and __Block_byref_x_VarName struct to find the actual 154 value of the variable. The function addBlockByrefType does this. */ 155 DIType subType = Ty; 156 uint16_t tag = Ty.getTag(); 157 158 if (tag == dwarf::DW_TAG_pointer_type) 159 subType = resolve(DIDerivedType(Ty).getTypeDerivedFrom()); 160 161 DIArray Elements = DICompositeType(subType).getTypeArray(); 162 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) { 163 DIDerivedType DT = DIDerivedType(Elements.getElement(i)); 164 if (getName() == DT.getName()) 165 return (resolve(DT.getTypeDerivedFrom())); 166 } 167 } 168 return Ty; 169} 170 171} // end llvm namespace 172 173/// Return Dwarf Version by checking module flags. 174static unsigned getDwarfVersionFromModule(const Module *M) { 175 Value *Val = M->getModuleFlag("Dwarf Version"); 176 if (!Val) 177 return dwarf::DWARF_VERSION; 178 return cast<ConstantInt>(Val)->getZExtValue(); 179} 180 181DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M) 182 : Asm(A), MMI(Asm->MMI), FirstCU(0), 183 AbbreviationsSet(InitAbbreviationsSetSize), 184 SourceIdMap(DIEValueAllocator), 185 PrevLabel(NULL), GlobalCUIndexCount(0), 186 InfoHolder(A, &AbbreviationsSet, Abbreviations, "info_string", 187 DIEValueAllocator), 188 SkeletonAbbrevSet(InitAbbreviationsSetSize), 189 SkeletonHolder(A, &SkeletonAbbrevSet, SkeletonAbbrevs, "skel_string", 190 DIEValueAllocator) { 191 192 DwarfInfoSectionSym = DwarfAbbrevSectionSym = 0; 193 DwarfStrSectionSym = TextSectionSym = 0; 194 DwarfDebugRangeSectionSym = DwarfDebugLocSectionSym = DwarfLineSectionSym = 0; 195 DwarfAddrSectionSym = 0; 196 DwarfAbbrevDWOSectionSym = DwarfStrDWOSectionSym = 0; 197 FunctionBeginSym = FunctionEndSym = 0; 198 199 // Turn on accelerator tables for Darwin by default, pubnames by 200 // default for non-Darwin, and handle split dwarf. 201 bool IsDarwin = Triple(A->getTargetTriple()).isOSDarwin(); 202 203 if (DwarfAccelTables == Default) 204 HasDwarfAccelTables = IsDarwin; 205 else 206 HasDwarfAccelTables = DwarfAccelTables == Enable; 207 208 if (SplitDwarf == Default) 209 HasSplitDwarf = false; 210 else 211 HasSplitDwarf = SplitDwarf == Enable; 212 213 if (DwarfPubSections == Default) 214 HasDwarfPubSections = !IsDarwin; 215 else 216 HasDwarfPubSections = DwarfPubSections == Enable; 217 218 DwarfVersion = getDwarfVersionFromModule(MMI->getModule()); 219 220 { 221 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 222 beginModule(); 223 } 224} 225 226// Switch to the specified MCSection and emit an assembler 227// temporary label to it if SymbolStem is specified. 228static MCSymbol *emitSectionSym(AsmPrinter *Asm, const MCSection *Section, 229 const char *SymbolStem = 0) { 230 Asm->OutStreamer.SwitchSection(Section); 231 if (!SymbolStem) return 0; 232 233 MCSymbol *TmpSym = Asm->GetTempSymbol(SymbolStem); 234 Asm->OutStreamer.EmitLabel(TmpSym); 235 return TmpSym; 236} 237 238MCSymbol *DwarfUnits::getStringPoolSym() { 239 return Asm->GetTempSymbol(StringPref); 240} 241 242MCSymbol *DwarfUnits::getStringPoolEntry(StringRef Str) { 243 std::pair<MCSymbol*, unsigned> &Entry = 244 StringPool.GetOrCreateValue(Str).getValue(); 245 if (Entry.first) return Entry.first; 246 247 Entry.second = NextStringPoolNumber++; 248 return Entry.first = Asm->GetTempSymbol(StringPref, Entry.second); 249} 250 251unsigned DwarfUnits::getStringPoolIndex(StringRef Str) { 252 std::pair<MCSymbol*, unsigned> &Entry = 253 StringPool.GetOrCreateValue(Str).getValue(); 254 if (Entry.first) return Entry.second; 255 256 Entry.second = NextStringPoolNumber++; 257 Entry.first = Asm->GetTempSymbol(StringPref, Entry.second); 258 return Entry.second; 259} 260 261unsigned DwarfUnits::getAddrPoolIndex(const MCSymbol *Sym) { 262 return getAddrPoolIndex(MCSymbolRefExpr::Create(Sym, Asm->OutContext)); 263} 264 265unsigned DwarfUnits::getAddrPoolIndex(const MCExpr *Sym) { 266 std::pair<DenseMap<const MCExpr *, unsigned>::iterator, bool> P = 267 AddressPool.insert(std::make_pair(Sym, NextAddrPoolNumber)); 268 if (P.second) 269 ++NextAddrPoolNumber; 270 return P.first->second; 271} 272 273// Define a unique number for the abbreviation. 274// 275void DwarfUnits::assignAbbrevNumber(DIEAbbrev &Abbrev) { 276 // Check the set for priors. 277 DIEAbbrev *InSet = AbbreviationsSet->GetOrInsertNode(&Abbrev); 278 279 // If it's newly added. 280 if (InSet == &Abbrev) { 281 // Add to abbreviation list. 282 Abbreviations.push_back(&Abbrev); 283 284 // Assign the vector position + 1 as its number. 285 Abbrev.setNumber(Abbreviations.size()); 286 } else { 287 // Assign existing abbreviation number. 288 Abbrev.setNumber(InSet->getNumber()); 289 } 290} 291 292static bool isObjCClass(StringRef Name) { 293 return Name.startswith("+") || Name.startswith("-"); 294} 295 296static bool hasObjCCategory(StringRef Name) { 297 if (!isObjCClass(Name)) return false; 298 299 return Name.find(") ") != StringRef::npos; 300} 301 302static void getObjCClassCategory(StringRef In, StringRef &Class, 303 StringRef &Category) { 304 if (!hasObjCCategory(In)) { 305 Class = In.slice(In.find('[') + 1, In.find(' ')); 306 Category = ""; 307 return; 308 } 309 310 Class = In.slice(In.find('[') + 1, In.find('(')); 311 Category = In.slice(In.find('[') + 1, In.find(' ')); 312 return; 313} 314 315static StringRef getObjCMethodName(StringRef In) { 316 return In.slice(In.find(' ') + 1, In.find(']')); 317} 318 319// Helper for sorting sections into a stable output order. 320static bool SectionSort(const MCSection *A, const MCSection *B) { 321 std::string LA = (A ? A->getLabelBeginName() : ""); 322 std::string LB = (B ? B->getLabelBeginName() : ""); 323 return LA < LB; 324} 325 326// Add the various names to the Dwarf accelerator table names. 327// TODO: Determine whether or not we should add names for programs 328// that do not have a DW_AT_name or DW_AT_linkage_name field - this 329// is only slightly different than the lookup of non-standard ObjC names. 330static void addSubprogramNames(CompileUnit *TheCU, DISubprogram SP, 331 DIE* Die) { 332 if (!SP.isDefinition()) return; 333 TheCU->addAccelName(SP.getName(), Die); 334 335 // If the linkage name is different than the name, go ahead and output 336 // that as well into the name table. 337 if (SP.getLinkageName() != "" && SP.getName() != SP.getLinkageName()) 338 TheCU->addAccelName(SP.getLinkageName(), Die); 339 340 // If this is an Objective-C selector name add it to the ObjC accelerator 341 // too. 342 if (isObjCClass(SP.getName())) { 343 StringRef Class, Category; 344 getObjCClassCategory(SP.getName(), Class, Category); 345 TheCU->addAccelObjC(Class, Die); 346 if (Category != "") 347 TheCU->addAccelObjC(Category, Die); 348 // Also add the base method name to the name table. 349 TheCU->addAccelName(getObjCMethodName(SP.getName()), Die); 350 } 351} 352 353/// isSubprogramContext - Return true if Context is either a subprogram 354/// or another context nested inside a subprogram. 355bool DwarfDebug::isSubprogramContext(const MDNode *Context) { 356 if (!Context) 357 return false; 358 DIDescriptor D(Context); 359 if (D.isSubprogram()) 360 return true; 361 if (D.isType()) 362 return isSubprogramContext(resolve(DIType(Context).getContext())); 363 return false; 364} 365 366// Find DIE for the given subprogram and attach appropriate DW_AT_low_pc 367// and DW_AT_high_pc attributes. If there are global variables in this 368// scope then create and insert DIEs for these variables. 369DIE *DwarfDebug::updateSubprogramScopeDIE(CompileUnit *SPCU, 370 const MDNode *SPNode) { 371 DIE *SPDie = SPCU->getDIE(SPNode); 372 373 assert(SPDie && "Unable to find subprogram DIE!"); 374 DISubprogram SP(SPNode); 375 376 // If we're updating an abstract DIE, then we will be adding the children and 377 // object pointer later on. But what we don't want to do is process the 378 // concrete DIE twice. 379 if (DIE *AbsSPDIE = AbstractSPDies.lookup(SPNode)) { 380 // Pick up abstract subprogram DIE. 381 SPDie = SPCU->createAndAddDIE(dwarf::DW_TAG_subprogram, *SPCU->getCUDie()); 382 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_abstract_origin, AbsSPDIE); 383 } else { 384 DISubprogram SPDecl = SP.getFunctionDeclaration(); 385 if (!SPDecl.isSubprogram()) { 386 // There is not any need to generate specification DIE for a function 387 // defined at compile unit level. If a function is defined inside another 388 // function then gdb prefers the definition at top level and but does not 389 // expect specification DIE in parent function. So avoid creating 390 // specification DIE for a function defined inside a function. 391 DIScope SPContext = resolve(SP.getContext()); 392 if (SP.isDefinition() && !SPContext.isCompileUnit() && 393 !SPContext.isFile() && 394 !isSubprogramContext(SPContext)) { 395 SPCU->addFlag(SPDie, dwarf::DW_AT_declaration); 396 397 // Add arguments. 398 DICompositeType SPTy = SP.getType(); 399 DIArray Args = SPTy.getTypeArray(); 400 uint16_t SPTag = SPTy.getTag(); 401 if (SPTag == dwarf::DW_TAG_subroutine_type) 402 for (unsigned i = 1, N = Args.getNumElements(); i < N; ++i) { 403 DIE *Arg = 404 SPCU->createAndAddDIE(dwarf::DW_TAG_formal_parameter, *SPDie); 405 DIType ATy = DIType(Args.getElement(i)); 406 SPCU->addType(Arg, ATy); 407 if (ATy.isArtificial()) 408 SPCU->addFlag(Arg, dwarf::DW_AT_artificial); 409 if (ATy.isObjectPointer()) 410 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_object_pointer, Arg); 411 } 412 DIE *SPDeclDie = SPDie; 413 SPDie = 414 SPCU->createAndAddDIE(dwarf::DW_TAG_subprogram, *SPCU->getCUDie()); 415 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_specification, SPDeclDie); 416 } 417 } 418 } 419 420 SPCU->addLabelAddress(SPDie, dwarf::DW_AT_low_pc, 421 Asm->GetTempSymbol("func_begin", 422 Asm->getFunctionNumber())); 423 SPCU->addLabelAddress(SPDie, dwarf::DW_AT_high_pc, 424 Asm->GetTempSymbol("func_end", 425 Asm->getFunctionNumber())); 426 const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo(); 427 MachineLocation Location(RI->getFrameRegister(*Asm->MF)); 428 SPCU->addAddress(SPDie, dwarf::DW_AT_frame_base, Location); 429 430 // Add name to the name table, we do this here because we're guaranteed 431 // to have concrete versions of our DW_TAG_subprogram nodes. 432 addSubprogramNames(SPCU, SP, SPDie); 433 434 return SPDie; 435} 436 437/// Check whether we should create a DIE for the given Scope, return true 438/// if we don't create a DIE (the corresponding DIE is null). 439bool DwarfDebug::isLexicalScopeDIENull(LexicalScope *Scope) { 440 if (Scope->isAbstractScope()) 441 return false; 442 443 // We don't create a DIE if there is no Range. 444 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 445 if (Ranges.empty()) 446 return true; 447 448 if (Ranges.size() > 1) 449 return false; 450 451 // We don't create a DIE if we have a single Range and the end label 452 // is null. 453 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 454 MCSymbol *End = getLabelAfterInsn(RI->second); 455 return !End; 456} 457 458// Construct new DW_TAG_lexical_block for this scope and attach 459// DW_AT_low_pc/DW_AT_high_pc labels. 460DIE *DwarfDebug::constructLexicalScopeDIE(CompileUnit *TheCU, 461 LexicalScope *Scope) { 462 if (isLexicalScopeDIENull(Scope)) 463 return 0; 464 465 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_lexical_block); 466 if (Scope->isAbstractScope()) 467 return ScopeDIE; 468 469 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 470 // If we have multiple ranges, emit them into the range section. 471 if (Ranges.size() > 1) { 472 // .debug_range section has not been laid out yet. Emit offset in 473 // .debug_range as a uint, size 4, for now. emitDIE will handle 474 // DW_AT_ranges appropriately. 475 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_ranges, dwarf::DW_FORM_data4, 476 DebugRangeSymbols.size() 477 * Asm->getDataLayout().getPointerSize()); 478 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 479 RE = Ranges.end(); RI != RE; ++RI) { 480 DebugRangeSymbols.push_back(getLabelBeforeInsn(RI->first)); 481 DebugRangeSymbols.push_back(getLabelAfterInsn(RI->second)); 482 } 483 484 // Terminate the range list. 485 DebugRangeSymbols.push_back(NULL); 486 DebugRangeSymbols.push_back(NULL); 487 return ScopeDIE; 488 } 489 490 // Construct the address range for this DIE. 491 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 492 MCSymbol *Start = getLabelBeforeInsn(RI->first); 493 MCSymbol *End = getLabelAfterInsn(RI->second); 494 assert(End && "End label should not be null!"); 495 496 assert(Start->isDefined() && "Invalid starting label for an inlined scope!"); 497 assert(End->isDefined() && "Invalid end label for an inlined scope!"); 498 499 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_low_pc, Start); 500 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_high_pc, End); 501 502 return ScopeDIE; 503} 504 505// This scope represents inlined body of a function. Construct DIE to 506// represent this concrete inlined copy of the function. 507DIE *DwarfDebug::constructInlinedScopeDIE(CompileUnit *TheCU, 508 LexicalScope *Scope) { 509 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 510 assert(Ranges.empty() == false && 511 "LexicalScope does not have instruction markers!"); 512 513 if (!Scope->getScopeNode()) 514 return NULL; 515 DIScope DS(Scope->getScopeNode()); 516 DISubprogram InlinedSP = getDISubprogram(DS); 517 DIE *OriginDIE = TheCU->getDIE(InlinedSP); 518 if (!OriginDIE) { 519 DEBUG(dbgs() << "Unable to find original DIE for an inlined subprogram."); 520 return NULL; 521 } 522 523 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_inlined_subroutine); 524 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_abstract_origin, OriginDIE); 525 526 if (Ranges.size() > 1) { 527 // .debug_range section has not been laid out yet. Emit offset in 528 // .debug_range as a uint, size 4, for now. emitDIE will handle 529 // DW_AT_ranges appropriately. 530 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_ranges, dwarf::DW_FORM_data4, 531 DebugRangeSymbols.size() 532 * Asm->getDataLayout().getPointerSize()); 533 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 534 RE = Ranges.end(); RI != RE; ++RI) { 535 DebugRangeSymbols.push_back(getLabelBeforeInsn(RI->first)); 536 DebugRangeSymbols.push_back(getLabelAfterInsn(RI->second)); 537 } 538 DebugRangeSymbols.push_back(NULL); 539 DebugRangeSymbols.push_back(NULL); 540 } else { 541 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 542 MCSymbol *StartLabel = getLabelBeforeInsn(RI->first); 543 MCSymbol *EndLabel = getLabelAfterInsn(RI->second); 544 545 if (StartLabel == 0 || EndLabel == 0) 546 llvm_unreachable("Unexpected Start and End labels for an inlined scope!"); 547 548 assert(StartLabel->isDefined() && 549 "Invalid starting label for an inlined scope!"); 550 assert(EndLabel->isDefined() && "Invalid end label for an inlined scope!"); 551 552 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_low_pc, StartLabel); 553 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_high_pc, EndLabel); 554 } 555 556 InlinedSubprogramDIEs.insert(OriginDIE); 557 558 // Add the call site information to the DIE. 559 DILocation DL(Scope->getInlinedAt()); 560 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_file, None, 561 getOrCreateSourceID(DL.getFilename(), DL.getDirectory(), 562 TheCU->getUniqueID())); 563 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_line, None, DL.getLineNumber()); 564 565 // Add name to the name table, we do this here because we're guaranteed 566 // to have concrete versions of our DW_TAG_inlined_subprogram nodes. 567 addSubprogramNames(TheCU, InlinedSP, ScopeDIE); 568 569 return ScopeDIE; 570} 571 572DIE *DwarfDebug::createScopeChildrenDIE(CompileUnit *TheCU, LexicalScope *Scope, 573 SmallVectorImpl<DIE*> &Children) { 574 DIE *ObjectPointer = NULL; 575 576 // Collect arguments for current function. 577 if (LScopes.isCurrentFunctionScope(Scope)) 578 for (unsigned i = 0, N = CurrentFnArguments.size(); i < N; ++i) 579 if (DbgVariable *ArgDV = CurrentFnArguments[i]) 580 if (DIE *Arg = 581 TheCU->constructVariableDIE(ArgDV, Scope->isAbstractScope())) { 582 Children.push_back(Arg); 583 if (ArgDV->isObjectPointer()) ObjectPointer = Arg; 584 } 585 586 // Collect lexical scope children first. 587 const SmallVectorImpl<DbgVariable *> &Variables =ScopeVariables.lookup(Scope); 588 for (unsigned i = 0, N = Variables.size(); i < N; ++i) 589 if (DIE *Variable = 590 TheCU->constructVariableDIE(Variables[i], Scope->isAbstractScope())) { 591 Children.push_back(Variable); 592 if (Variables[i]->isObjectPointer()) ObjectPointer = Variable; 593 } 594 const SmallVectorImpl<LexicalScope *> &Scopes = Scope->getChildren(); 595 for (unsigned j = 0, M = Scopes.size(); j < M; ++j) 596 if (DIE *Nested = constructScopeDIE(TheCU, Scopes[j])) 597 Children.push_back(Nested); 598 return ObjectPointer; 599} 600 601// Construct a DIE for this scope. 602DIE *DwarfDebug::constructScopeDIE(CompileUnit *TheCU, LexicalScope *Scope) { 603 if (!Scope || !Scope->getScopeNode()) 604 return NULL; 605 606 DIScope DS(Scope->getScopeNode()); 607 608 SmallVector<DIE *, 8> Children; 609 DIE *ObjectPointer = NULL; 610 bool ChildrenCreated = false; 611 612 // We try to create the scope DIE first, then the children DIEs. This will 613 // avoid creating un-used children then removing them later when we find out 614 // the scope DIE is null. 615 DIE *ScopeDIE = NULL; 616 if (Scope->getInlinedAt()) 617 ScopeDIE = constructInlinedScopeDIE(TheCU, Scope); 618 else if (DS.isSubprogram()) { 619 ProcessedSPNodes.insert(DS); 620 if (Scope->isAbstractScope()) { 621 ScopeDIE = TheCU->getDIE(DS); 622 // Note down abstract DIE. 623 if (ScopeDIE) 624 AbstractSPDies.insert(std::make_pair(DS, ScopeDIE)); 625 } 626 else 627 ScopeDIE = updateSubprogramScopeDIE(TheCU, DS); 628 } 629 else { 630 // Early exit when we know the scope DIE is going to be null. 631 if (isLexicalScopeDIENull(Scope)) 632 return NULL; 633 634 // We create children here when we know the scope DIE is not going to be 635 // null and the children will be added to the scope DIE. 636 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children); 637 ChildrenCreated = true; 638 639 // There is no need to emit empty lexical block DIE. 640 std::pair<ImportedEntityMap::const_iterator, 641 ImportedEntityMap::const_iterator> Range = std::equal_range( 642 ScopesWithImportedEntities.begin(), ScopesWithImportedEntities.end(), 643 std::pair<const MDNode *, const MDNode *>(DS, (const MDNode*)0), 644 less_first()); 645 if (Children.empty() && Range.first == Range.second) 646 return NULL; 647 ScopeDIE = constructLexicalScopeDIE(TheCU, Scope); 648 assert(ScopeDIE && "Scope DIE should not be null."); 649 for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second; 650 ++i) 651 constructImportedEntityDIE(TheCU, i->second, ScopeDIE); 652 } 653 654 if (!ScopeDIE) { 655 assert(Children.empty() && 656 "We create children only when the scope DIE is not null."); 657 return NULL; 658 } 659 if (!ChildrenCreated) 660 // We create children when the scope DIE is not null. 661 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children); 662 663 // Add children 664 for (SmallVectorImpl<DIE *>::iterator I = Children.begin(), 665 E = Children.end(); I != E; ++I) 666 ScopeDIE->addChild(*I); 667 668 if (DS.isSubprogram() && ObjectPointer != NULL) 669 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, ObjectPointer); 670 671 if (DS.isSubprogram()) 672 TheCU->addPubTypes(DISubprogram(DS)); 673 674 return ScopeDIE; 675} 676 677// Look up the source id with the given directory and source file names. 678// If none currently exists, create a new id and insert it in the 679// SourceIds map. This can update DirectoryNames and SourceFileNames maps 680// as well. 681unsigned DwarfDebug::getOrCreateSourceID(StringRef FileName, 682 StringRef DirName, unsigned CUID) { 683 // If we use .loc in assembly, we can't separate .file entries according to 684 // compile units. Thus all files will belong to the default compile unit. 685 686 // FIXME: add a better feature test than hasRawTextSupport. Even better, 687 // extend .file to support this. 688 if (Asm->TM.hasMCUseLoc() && Asm->OutStreamer.hasRawTextSupport()) 689 CUID = 0; 690 691 // If FE did not provide a file name, then assume stdin. 692 if (FileName.empty()) 693 return getOrCreateSourceID("<stdin>", StringRef(), CUID); 694 695 // TODO: this might not belong here. See if we can factor this better. 696 if (DirName == CompilationDir) 697 DirName = ""; 698 699 // FileIDCUMap stores the current ID for the given compile unit. 700 unsigned SrcId = FileIDCUMap[CUID] + 1; 701 702 // We look up the CUID/file/dir by concatenating them with a zero byte. 703 SmallString<128> NamePair; 704 NamePair += utostr(CUID); 705 NamePair += '\0'; 706 NamePair += DirName; 707 NamePair += '\0'; // Zero bytes are not allowed in paths. 708 NamePair += FileName; 709 710 StringMapEntry<unsigned> &Ent = SourceIdMap.GetOrCreateValue(NamePair, SrcId); 711 if (Ent.getValue() != SrcId) 712 return Ent.getValue(); 713 714 FileIDCUMap[CUID] = SrcId; 715 // Print out a .file directive to specify files for .loc directives. 716 Asm->OutStreamer.EmitDwarfFileDirective(SrcId, DirName, FileName, CUID); 717 718 return SrcId; 719} 720 721// Create new CompileUnit for the given metadata node with tag 722// DW_TAG_compile_unit. 723CompileUnit *DwarfDebug::constructCompileUnit(const MDNode *N) { 724 DICompileUnit DIUnit(N); 725 StringRef FN = DIUnit.getFilename(); 726 CompilationDir = DIUnit.getDirectory(); 727 728 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit); 729 CompileUnit *NewCU = 730 new CompileUnit(GlobalCUIndexCount++, Die, N, Asm, this, &InfoHolder); 731 732 FileIDCUMap[NewCU->getUniqueID()] = 0; 733 // Call this to emit a .file directive if it wasn't emitted for the source 734 // file this CU comes from yet. 735 getOrCreateSourceID(FN, CompilationDir, NewCU->getUniqueID()); 736 737 NewCU->addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer()); 738 NewCU->addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2, 739 DIUnit.getLanguage()); 740 NewCU->addString(Die, dwarf::DW_AT_name, FN); 741 742 // 2.17.1 requires that we use DW_AT_low_pc for a single entry point 743 // into an entity. We're using 0 (or a NULL label) for this. For 744 // split dwarf it's in the skeleton CU so omit it here. 745 if (!useSplitDwarf()) 746 NewCU->addLabelAddress(Die, dwarf::DW_AT_low_pc, NULL); 747 748 // Define start line table label for each Compile Unit. 749 MCSymbol *LineTableStartSym = Asm->GetTempSymbol("line_table_start", 750 NewCU->getUniqueID()); 751 Asm->OutStreamer.getContext().setMCLineTableSymbol(LineTableStartSym, 752 NewCU->getUniqueID()); 753 754 // Use a single line table if we are using .loc and generating assembly. 755 bool UseTheFirstCU = 756 (Asm->TM.hasMCUseLoc() && Asm->OutStreamer.hasRawTextSupport()) || 757 (NewCU->getUniqueID() == 0); 758 759 if (!useSplitDwarf()) { 760 // DW_AT_stmt_list is a offset of line number information for this 761 // compile unit in debug_line section. For split dwarf this is 762 // left in the skeleton CU and so not included. 763 // The line table entries are not always emitted in assembly, so it 764 // is not okay to use line_table_start here. 765 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 766 NewCU->addLabel(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 767 UseTheFirstCU ? Asm->GetTempSymbol("section_line") 768 : LineTableStartSym); 769 else if (UseTheFirstCU) 770 NewCU->addUInt(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4, 0); 771 else 772 NewCU->addDelta(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4, 773 LineTableStartSym, DwarfLineSectionSym); 774 775 // If we're using split dwarf the compilation dir is going to be in the 776 // skeleton CU and so we don't need to duplicate it here. 777 if (!CompilationDir.empty()) 778 NewCU->addString(Die, dwarf::DW_AT_comp_dir, CompilationDir); 779 780 // Flags to let the linker know we have emitted new style pubnames. Only 781 // emit it here if we don't have a skeleton CU for split dwarf. 782 if (GenerateGnuPubSections) { 783 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 784 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubnames, 785 dwarf::DW_FORM_sec_offset, 786 Asm->GetTempSymbol("gnu_pubnames", 787 NewCU->getUniqueID())); 788 else 789 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_data4, 790 Asm->GetTempSymbol("gnu_pubnames", 791 NewCU->getUniqueID()), 792 DwarfGnuPubNamesSectionSym); 793 794 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 795 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubtypes, 796 dwarf::DW_FORM_sec_offset, 797 Asm->GetTempSymbol("gnu_pubtypes", 798 NewCU->getUniqueID())); 799 else 800 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_data4, 801 Asm->GetTempSymbol("gnu_pubtypes", 802 NewCU->getUniqueID()), 803 DwarfGnuPubTypesSectionSym); 804 } 805 } 806 807 if (DIUnit.isOptimized()) 808 NewCU->addFlag(Die, dwarf::DW_AT_APPLE_optimized); 809 810 StringRef Flags = DIUnit.getFlags(); 811 if (!Flags.empty()) 812 NewCU->addString(Die, dwarf::DW_AT_APPLE_flags, Flags); 813 814 if (unsigned RVer = DIUnit.getRunTimeVersion()) 815 NewCU->addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers, 816 dwarf::DW_FORM_data1, RVer); 817 818 if (!FirstCU) 819 FirstCU = NewCU; 820 821 InfoHolder.addUnit(NewCU); 822 823 CUMap.insert(std::make_pair(N, NewCU)); 824 CUDieMap.insert(std::make_pair(Die, NewCU)); 825 return NewCU; 826} 827 828// Construct subprogram DIE. 829void DwarfDebug::constructSubprogramDIE(CompileUnit *TheCU, const MDNode *N) { 830 // FIXME: We should only call this routine once, however, during LTO if a 831 // program is defined in multiple CUs we could end up calling it out of 832 // beginModule as we walk the CUs. 833 834 CompileUnit *&CURef = SPMap[N]; 835 if (CURef) 836 return; 837 CURef = TheCU; 838 839 DISubprogram SP(N); 840 if (!SP.isDefinition()) 841 // This is a method declaration which will be handled while constructing 842 // class type. 843 return; 844 845 DIE *SubprogramDie = TheCU->getOrCreateSubprogramDIE(SP); 846 847 // Expose as a global name. 848 TheCU->addGlobalName(SP.getName(), SubprogramDie, resolve(SP.getContext())); 849} 850 851void DwarfDebug::constructImportedEntityDIE(CompileUnit *TheCU, 852 const MDNode *N) { 853 DIImportedEntity Module(N); 854 if (!Module.Verify()) 855 return; 856 if (DIE *D = TheCU->getOrCreateContextDIE(Module.getContext())) 857 constructImportedEntityDIE(TheCU, Module, D); 858} 859 860void DwarfDebug::constructImportedEntityDIE(CompileUnit *TheCU, const MDNode *N, 861 DIE *Context) { 862 DIImportedEntity Module(N); 863 if (!Module.Verify()) 864 return; 865 return constructImportedEntityDIE(TheCU, Module, Context); 866} 867 868void DwarfDebug::constructImportedEntityDIE(CompileUnit *TheCU, 869 const DIImportedEntity &Module, 870 DIE *Context) { 871 assert(Module.Verify() && 872 "Use one of the MDNode * overloads to handle invalid metadata"); 873 assert(Context && "Should always have a context for an imported_module"); 874 DIE *IMDie = new DIE(Module.getTag()); 875 TheCU->insertDIE(Module, IMDie); 876 DIE *EntityDie; 877 DIDescriptor Entity = Module.getEntity(); 878 if (Entity.isNameSpace()) 879 EntityDie = TheCU->getOrCreateNameSpace(DINameSpace(Entity)); 880 else if (Entity.isSubprogram()) 881 EntityDie = TheCU->getOrCreateSubprogramDIE(DISubprogram(Entity)); 882 else if (Entity.isType()) 883 EntityDie = TheCU->getOrCreateTypeDIE(DIType(Entity)); 884 else 885 EntityDie = TheCU->getDIE(Entity); 886 unsigned FileID = getOrCreateSourceID(Module.getContext().getFilename(), 887 Module.getContext().getDirectory(), 888 TheCU->getUniqueID()); 889 TheCU->addUInt(IMDie, dwarf::DW_AT_decl_file, None, FileID); 890 TheCU->addUInt(IMDie, dwarf::DW_AT_decl_line, None, Module.getLineNumber()); 891 TheCU->addDIEEntry(IMDie, dwarf::DW_AT_import, EntityDie); 892 StringRef Name = Module.getName(); 893 if (!Name.empty()) 894 TheCU->addString(IMDie, dwarf::DW_AT_name, Name); 895 Context->addChild(IMDie); 896} 897 898// Emit all Dwarf sections that should come prior to the content. Create 899// global DIEs and emit initial debug info sections. This is invoked by 900// the target AsmPrinter. 901void DwarfDebug::beginModule() { 902 if (DisableDebugInfoPrinting) 903 return; 904 905 const Module *M = MMI->getModule(); 906 907 // If module has named metadata anchors then use them, otherwise scan the 908 // module using debug info finder to collect debug info. 909 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu"); 910 if (!CU_Nodes) 911 return; 912 TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes); 913 914 // Emit initial sections so we can reference labels later. 915 emitSectionLabels(); 916 917 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) { 918 DICompileUnit CUNode(CU_Nodes->getOperand(i)); 919 CompileUnit *CU = constructCompileUnit(CUNode); 920 DIArray ImportedEntities = CUNode.getImportedEntities(); 921 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i) 922 ScopesWithImportedEntities.push_back(std::make_pair( 923 DIImportedEntity(ImportedEntities.getElement(i)).getContext(), 924 ImportedEntities.getElement(i))); 925 std::sort(ScopesWithImportedEntities.begin(), 926 ScopesWithImportedEntities.end(), less_first()); 927 DIArray GVs = CUNode.getGlobalVariables(); 928 for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i) 929 CU->createGlobalVariableDIE(GVs.getElement(i)); 930 DIArray SPs = CUNode.getSubprograms(); 931 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) 932 constructSubprogramDIE(CU, SPs.getElement(i)); 933 DIArray EnumTypes = CUNode.getEnumTypes(); 934 for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i) 935 CU->getOrCreateTypeDIE(EnumTypes.getElement(i)); 936 DIArray RetainedTypes = CUNode.getRetainedTypes(); 937 for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i) 938 CU->getOrCreateTypeDIE(RetainedTypes.getElement(i)); 939 // Emit imported_modules last so that the relevant context is already 940 // available. 941 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i) 942 constructImportedEntityDIE(CU, ImportedEntities.getElement(i)); 943 } 944 945 // Tell MMI that we have debug info. 946 MMI->setDebugInfoAvailability(true); 947 948 // Prime section data. 949 SectionMap[Asm->getObjFileLowering().getTextSection()]; 950} 951 952// Attach DW_AT_inline attribute with inlined subprogram DIEs. 953void DwarfDebug::computeInlinedDIEs() { 954 // Attach DW_AT_inline attribute with inlined subprogram DIEs. 955 for (SmallPtrSet<DIE *, 4>::iterator AI = InlinedSubprogramDIEs.begin(), 956 AE = InlinedSubprogramDIEs.end(); AI != AE; ++AI) { 957 DIE *ISP = *AI; 958 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined); 959 } 960 for (DenseMap<const MDNode *, DIE *>::iterator AI = AbstractSPDies.begin(), 961 AE = AbstractSPDies.end(); AI != AE; ++AI) { 962 DIE *ISP = AI->second; 963 if (InlinedSubprogramDIEs.count(ISP)) 964 continue; 965 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined); 966 } 967} 968 969// Collect info for variables that were optimized out. 970void DwarfDebug::collectDeadVariables() { 971 const Module *M = MMI->getModule(); 972 973 if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) { 974 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) { 975 DICompileUnit TheCU(CU_Nodes->getOperand(i)); 976 DIArray Subprograms = TheCU.getSubprograms(); 977 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) { 978 DISubprogram SP(Subprograms.getElement(i)); 979 if (ProcessedSPNodes.count(SP) != 0) 980 continue; 981 if (!SP.isSubprogram()) 982 continue; 983 if (!SP.isDefinition()) 984 continue; 985 DIArray Variables = SP.getVariables(); 986 if (Variables.getNumElements() == 0) 987 continue; 988 989 // Construct subprogram DIE and add variables DIEs. 990 CompileUnit *SPCU = CUMap.lookup(TheCU); 991 assert(SPCU && "Unable to find Compile Unit!"); 992 // FIXME: See the comment in constructSubprogramDIE about duplicate 993 // subprogram DIEs. 994 constructSubprogramDIE(SPCU, SP); 995 DIE *SPDIE = SPCU->getDIE(SP); 996 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) { 997 DIVariable DV(Variables.getElement(vi)); 998 if (!DV.isVariable()) 999 continue; 1000 DbgVariable NewVar(DV, NULL, this); 1001 if (DIE *VariableDIE = 1002 SPCU->constructVariableDIE(&NewVar, false)) 1003 SPDIE->addChild(VariableDIE); 1004 } 1005 } 1006 } 1007 } 1008} 1009 1010// Type Signature [7.27] and ODR Hash code. 1011 1012/// \brief Grabs the string in whichever attribute is passed in and returns 1013/// a reference to it. Returns "" if the attribute doesn't exist. 1014static StringRef getDIEStringAttr(DIE *Die, unsigned Attr) { 1015 DIEValue *V = Die->findAttribute(Attr); 1016 1017 if (DIEString *S = dyn_cast_or_null<DIEString>(V)) 1018 return S->getString(); 1019 1020 return StringRef(""); 1021} 1022 1023/// Return true if the current DIE is contained within an anonymous namespace. 1024static bool isContainedInAnonNamespace(DIE *Die) { 1025 DIE *Parent = Die->getParent(); 1026 1027 while (Parent) { 1028 if (Parent->getTag() == dwarf::DW_TAG_namespace && 1029 getDIEStringAttr(Parent, dwarf::DW_AT_name) == "") 1030 return true; 1031 Parent = Parent->getParent(); 1032 } 1033 1034 return false; 1035} 1036 1037/// Test if the current CU language is C++ and that we have 1038/// a named type that is not contained in an anonymous namespace. 1039static bool shouldAddODRHash(CompileUnit *CU, DIE *Die) { 1040 return CU->getLanguage() == dwarf::DW_LANG_C_plus_plus && 1041 getDIEStringAttr(Die, dwarf::DW_AT_name) != "" && 1042 !isContainedInAnonNamespace(Die); 1043} 1044 1045void DwarfDebug::finalizeModuleInfo() { 1046 // Collect info for variables that were optimized out. 1047 collectDeadVariables(); 1048 1049 // Attach DW_AT_inline attribute with inlined subprogram DIEs. 1050 computeInlinedDIEs(); 1051 1052 // Split out type units and conditionally add an ODR tag to the split 1053 // out type. 1054 // FIXME: Do type splitting. 1055 for (unsigned i = 0, e = TypeUnits.size(); i != e; ++i) { 1056 DIE *Die = TypeUnits[i]; 1057 DIEHash Hash; 1058 // If we've requested ODR hashes and it's applicable for an ODR hash then 1059 // add the ODR signature now. 1060 // FIXME: This should be added onto the type unit, not the type, but this 1061 // works as an intermediate stage. 1062 if (GenerateODRHash && shouldAddODRHash(CUMap.begin()->second, Die)) 1063 CUMap.begin()->second->addUInt(Die, dwarf::DW_AT_GNU_odr_signature, 1064 dwarf::DW_FORM_data8, 1065 Hash.computeDIEODRSignature(*Die)); 1066 } 1067 1068 // Handle anything that needs to be done on a per-cu basis. 1069 for (DenseMap<const MDNode *, CompileUnit *>::iterator CUI = CUMap.begin(), 1070 CUE = CUMap.end(); 1071 CUI != CUE; ++CUI) { 1072 CompileUnit *TheCU = CUI->second; 1073 // Emit DW_AT_containing_type attribute to connect types with their 1074 // vtable holding type. 1075 TheCU->constructContainingTypeDIEs(); 1076 1077 // If we're splitting the dwarf out now that we've got the entire 1078 // CU then construct a skeleton CU based upon it. 1079 if (useSplitDwarf()) { 1080 uint64_t ID = 0; 1081 if (GenerateCUHash) { 1082 DIEHash CUHash; 1083 ID = CUHash.computeCUSignature(*TheCU->getCUDie()); 1084 } 1085 // This should be a unique identifier when we want to build .dwp files. 1086 TheCU->addUInt(TheCU->getCUDie(), dwarf::DW_AT_GNU_dwo_id, 1087 dwarf::DW_FORM_data8, ID); 1088 // Now construct the skeleton CU associated. 1089 CompileUnit *SkCU = constructSkeletonCU(TheCU); 1090 // This should be a unique identifier when we want to build .dwp files. 1091 SkCU->addUInt(SkCU->getCUDie(), dwarf::DW_AT_GNU_dwo_id, 1092 dwarf::DW_FORM_data8, ID); 1093 } 1094 } 1095 1096 // Compute DIE offsets and sizes. 1097 InfoHolder.computeSizeAndOffsets(); 1098 if (useSplitDwarf()) 1099 SkeletonHolder.computeSizeAndOffsets(); 1100} 1101 1102void DwarfDebug::endSections() { 1103 // Filter labels by section. 1104 for (size_t n = 0; n < ArangeLabels.size(); n++) { 1105 const SymbolCU &SCU = ArangeLabels[n]; 1106 if (SCU.Sym->isInSection()) { 1107 // Make a note of this symbol and it's section. 1108 const MCSection *Section = &SCU.Sym->getSection(); 1109 if (!Section->getKind().isMetadata()) 1110 SectionMap[Section].push_back(SCU); 1111 } else { 1112 // Some symbols (e.g. common/bss on mach-o) can have no section but still 1113 // appear in the output. This sucks as we rely on sections to build 1114 // arange spans. We can do it without, but it's icky. 1115 SectionMap[NULL].push_back(SCU); 1116 } 1117 } 1118 1119 // Build a list of sections used. 1120 std::vector<const MCSection *> Sections; 1121 for (SectionMapType::iterator it = SectionMap.begin(); it != SectionMap.end(); 1122 it++) { 1123 const MCSection *Section = it->first; 1124 Sections.push_back(Section); 1125 } 1126 1127 // Sort the sections into order. 1128 // This is only done to ensure consistent output order across different runs. 1129 std::sort(Sections.begin(), Sections.end(), SectionSort); 1130 1131 // Add terminating symbols for each section. 1132 for (unsigned ID=0;ID<Sections.size();ID++) { 1133 const MCSection *Section = Sections[ID]; 1134 MCSymbol *Sym = NULL; 1135 1136 if (Section) { 1137 // We can't call MCSection::getLabelEndName, as it's only safe to do so 1138 // if we know the section name up-front. For user-created sections, the resulting 1139 // label may not be valid to use as a label. (section names can use a greater 1140 // set of characters on some systems) 1141 Sym = Asm->GetTempSymbol("debug_end", ID); 1142 Asm->OutStreamer.SwitchSection(Section); 1143 Asm->OutStreamer.EmitLabel(Sym); 1144 } 1145 1146 // Insert a final terminator. 1147 SectionMap[Section].push_back(SymbolCU(NULL, Sym)); 1148 } 1149} 1150 1151// Emit all Dwarf sections that should come after the content. 1152void DwarfDebug::endModule() { 1153 1154 if (!FirstCU) return; 1155 1156 // End any existing sections. 1157 // TODO: Does this need to happen? 1158 endSections(); 1159 1160 // Finalize the debug info for the module. 1161 finalizeModuleInfo(); 1162 1163 if (!useSplitDwarf()) { 1164 emitDebugStr(); 1165 1166 // Emit all the DIEs into a debug info section. 1167 emitDebugInfo(); 1168 1169 // Corresponding abbreviations into a abbrev section. 1170 emitAbbreviations(); 1171 1172 // Emit info into a debug loc section. 1173 emitDebugLoc(); 1174 1175 // Emit info into a debug aranges section. 1176 emitDebugARanges(); 1177 1178 // Emit info into a debug ranges section. 1179 emitDebugRanges(); 1180 1181 // Emit info into a debug macinfo section. 1182 emitDebugMacInfo(); 1183 1184 } else { 1185 // TODO: Fill this in for separated debug sections and separate 1186 // out information into new sections. 1187 emitDebugStr(); 1188 if (useSplitDwarf()) 1189 emitDebugStrDWO(); 1190 1191 // Emit the debug info section and compile units. 1192 emitDebugInfo(); 1193 emitDebugInfoDWO(); 1194 1195 // Corresponding abbreviations into a abbrev section. 1196 emitAbbreviations(); 1197 emitDebugAbbrevDWO(); 1198 1199 // Emit info into a debug loc section. 1200 emitDebugLoc(); 1201 1202 // Emit info into a debug aranges section. 1203 emitDebugARanges(); 1204 1205 // Emit info into a debug ranges section. 1206 emitDebugRanges(); 1207 1208 // Emit info into a debug macinfo section. 1209 emitDebugMacInfo(); 1210 1211 // Emit DWO addresses. 1212 InfoHolder.emitAddresses(Asm->getObjFileLowering().getDwarfAddrSection()); 1213 1214 } 1215 1216 // Emit info into the dwarf accelerator table sections. 1217 if (useDwarfAccelTables()) { 1218 emitAccelNames(); 1219 emitAccelObjC(); 1220 emitAccelNamespaces(); 1221 emitAccelTypes(); 1222 } 1223 1224 // Emit the pubnames and pubtypes sections if requested. 1225 if (HasDwarfPubSections) { 1226 emitDebugPubNames(GenerateGnuPubSections); 1227 emitDebugPubTypes(GenerateGnuPubSections); 1228 } 1229 1230 // clean up. 1231 SPMap.clear(); 1232 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 1233 E = CUMap.end(); I != E; ++I) 1234 delete I->second; 1235 1236 for (SmallVectorImpl<CompileUnit *>::iterator I = SkeletonCUs.begin(), 1237 E = SkeletonCUs.end(); I != E; ++I) 1238 delete *I; 1239 1240 // Reset these for the next Module if we have one. 1241 FirstCU = NULL; 1242} 1243 1244// Find abstract variable, if any, associated with Var. 1245DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &DV, 1246 DebugLoc ScopeLoc) { 1247 LLVMContext &Ctx = DV->getContext(); 1248 // More then one inlined variable corresponds to one abstract variable. 1249 DIVariable Var = cleanseInlinedVariable(DV, Ctx); 1250 DbgVariable *AbsDbgVariable = AbstractVariables.lookup(Var); 1251 if (AbsDbgVariable) 1252 return AbsDbgVariable; 1253 1254 LexicalScope *Scope = LScopes.findAbstractScope(ScopeLoc.getScope(Ctx)); 1255 if (!Scope) 1256 return NULL; 1257 1258 AbsDbgVariable = new DbgVariable(Var, NULL, this); 1259 addScopeVariable(Scope, AbsDbgVariable); 1260 AbstractVariables[Var] = AbsDbgVariable; 1261 return AbsDbgVariable; 1262} 1263 1264// If Var is a current function argument then add it to CurrentFnArguments list. 1265bool DwarfDebug::addCurrentFnArgument(const MachineFunction *MF, 1266 DbgVariable *Var, LexicalScope *Scope) { 1267 if (!LScopes.isCurrentFunctionScope(Scope)) 1268 return false; 1269 DIVariable DV = Var->getVariable(); 1270 if (DV.getTag() != dwarf::DW_TAG_arg_variable) 1271 return false; 1272 unsigned ArgNo = DV.getArgNumber(); 1273 if (ArgNo == 0) 1274 return false; 1275 1276 size_t Size = CurrentFnArguments.size(); 1277 if (Size == 0) 1278 CurrentFnArguments.resize(MF->getFunction()->arg_size()); 1279 // llvm::Function argument size is not good indicator of how many 1280 // arguments does the function have at source level. 1281 if (ArgNo > Size) 1282 CurrentFnArguments.resize(ArgNo * 2); 1283 CurrentFnArguments[ArgNo - 1] = Var; 1284 return true; 1285} 1286 1287// Collect variable information from side table maintained by MMI. 1288void 1289DwarfDebug::collectVariableInfoFromMMITable(const MachineFunction *MF, 1290 SmallPtrSet<const MDNode *, 16> &Processed) { 1291 MachineModuleInfo::VariableDbgInfoMapTy &VMap = MMI->getVariableDbgInfo(); 1292 for (MachineModuleInfo::VariableDbgInfoMapTy::iterator VI = VMap.begin(), 1293 VE = VMap.end(); VI != VE; ++VI) { 1294 const MDNode *Var = VI->first; 1295 if (!Var) continue; 1296 Processed.insert(Var); 1297 DIVariable DV(Var); 1298 const std::pair<unsigned, DebugLoc> &VP = VI->second; 1299 1300 LexicalScope *Scope = LScopes.findLexicalScope(VP.second); 1301 1302 // If variable scope is not found then skip this variable. 1303 if (Scope == 0) 1304 continue; 1305 1306 DbgVariable *AbsDbgVariable = findAbstractVariable(DV, VP.second); 1307 DbgVariable *RegVar = new DbgVariable(DV, AbsDbgVariable, this); 1308 RegVar->setFrameIndex(VP.first); 1309 if (!addCurrentFnArgument(MF, RegVar, Scope)) 1310 addScopeVariable(Scope, RegVar); 1311 if (AbsDbgVariable) 1312 AbsDbgVariable->setFrameIndex(VP.first); 1313 } 1314} 1315 1316// Return true if debug value, encoded by DBG_VALUE instruction, is in a 1317// defined reg. 1318static bool isDbgValueInDefinedReg(const MachineInstr *MI) { 1319 assert(MI->isDebugValue() && "Invalid DBG_VALUE machine instruction!"); 1320 return MI->getNumOperands() == 3 && 1321 MI->getOperand(0).isReg() && MI->getOperand(0).getReg() && 1322 (MI->getOperand(1).isImm() || 1323 (MI->getOperand(1).isReg() && MI->getOperand(1).getReg() == 0U)); 1324} 1325 1326// Get .debug_loc entry for the instruction range starting at MI. 1327static DotDebugLocEntry getDebugLocEntry(AsmPrinter *Asm, 1328 const MCSymbol *FLabel, 1329 const MCSymbol *SLabel, 1330 const MachineInstr *MI) { 1331 const MDNode *Var = MI->getOperand(MI->getNumOperands() - 1).getMetadata(); 1332 1333 assert(MI->getNumOperands() == 3); 1334 if (MI->getOperand(0).isReg()) { 1335 MachineLocation MLoc; 1336 // If the second operand is an immediate, this is a 1337 // register-indirect address. 1338 if (!MI->getOperand(1).isImm()) 1339 MLoc.set(MI->getOperand(0).getReg()); 1340 else 1341 MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm()); 1342 return DotDebugLocEntry(FLabel, SLabel, MLoc, Var); 1343 } 1344 if (MI->getOperand(0).isImm()) 1345 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getImm()); 1346 if (MI->getOperand(0).isFPImm()) 1347 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getFPImm()); 1348 if (MI->getOperand(0).isCImm()) 1349 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getCImm()); 1350 1351 llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!"); 1352} 1353 1354// Find variables for each lexical scope. 1355void 1356DwarfDebug::collectVariableInfo(const MachineFunction *MF, 1357 SmallPtrSet<const MDNode *, 16> &Processed) { 1358 1359 // Grab the variable info that was squirreled away in the MMI side-table. 1360 collectVariableInfoFromMMITable(MF, Processed); 1361 1362 for (SmallVectorImpl<const MDNode*>::const_iterator 1363 UVI = UserVariables.begin(), UVE = UserVariables.end(); UVI != UVE; 1364 ++UVI) { 1365 const MDNode *Var = *UVI; 1366 if (Processed.count(Var)) 1367 continue; 1368 1369 // History contains relevant DBG_VALUE instructions for Var and instructions 1370 // clobbering it. 1371 SmallVectorImpl<const MachineInstr*> &History = DbgValues[Var]; 1372 if (History.empty()) 1373 continue; 1374 const MachineInstr *MInsn = History.front(); 1375 1376 DIVariable DV(Var); 1377 LexicalScope *Scope = NULL; 1378 if (DV.getTag() == dwarf::DW_TAG_arg_variable && 1379 DISubprogram(DV.getContext()).describes(MF->getFunction())) 1380 Scope = LScopes.getCurrentFunctionScope(); 1381 else if (MDNode *IA = DV.getInlinedAt()) 1382 Scope = LScopes.findInlinedScope(DebugLoc::getFromDILocation(IA)); 1383 else 1384 Scope = LScopes.findLexicalScope(cast<MDNode>(DV->getOperand(1))); 1385 // If variable scope is not found then skip this variable. 1386 if (!Scope) 1387 continue; 1388 1389 Processed.insert(DV); 1390 assert(MInsn->isDebugValue() && "History must begin with debug value"); 1391 DbgVariable *AbsVar = findAbstractVariable(DV, MInsn->getDebugLoc()); 1392 DbgVariable *RegVar = new DbgVariable(DV, AbsVar, this); 1393 if (!addCurrentFnArgument(MF, RegVar, Scope)) 1394 addScopeVariable(Scope, RegVar); 1395 if (AbsVar) 1396 AbsVar->setMInsn(MInsn); 1397 1398 // Simplify ranges that are fully coalesced. 1399 if (History.size() <= 1 || (History.size() == 2 && 1400 MInsn->isIdenticalTo(History.back()))) { 1401 RegVar->setMInsn(MInsn); 1402 continue; 1403 } 1404 1405 // Handle multiple DBG_VALUE instructions describing one variable. 1406 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size()); 1407 1408 for (SmallVectorImpl<const MachineInstr*>::const_iterator 1409 HI = History.begin(), HE = History.end(); HI != HE; ++HI) { 1410 const MachineInstr *Begin = *HI; 1411 assert(Begin->isDebugValue() && "Invalid History entry"); 1412 1413 // Check if DBG_VALUE is truncating a range. 1414 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() 1415 && !Begin->getOperand(0).getReg()) 1416 continue; 1417 1418 // Compute the range for a register location. 1419 const MCSymbol *FLabel = getLabelBeforeInsn(Begin); 1420 const MCSymbol *SLabel = 0; 1421 1422 if (HI + 1 == HE) 1423 // If Begin is the last instruction in History then its value is valid 1424 // until the end of the function. 1425 SLabel = FunctionEndSym; 1426 else { 1427 const MachineInstr *End = HI[1]; 1428 DEBUG(dbgs() << "DotDebugLoc Pair:\n" 1429 << "\t" << *Begin << "\t" << *End << "\n"); 1430 if (End->isDebugValue()) 1431 SLabel = getLabelBeforeInsn(End); 1432 else { 1433 // End is a normal instruction clobbering the range. 1434 SLabel = getLabelAfterInsn(End); 1435 assert(SLabel && "Forgot label after clobber instruction"); 1436 ++HI; 1437 } 1438 } 1439 1440 // The value is valid until the next DBG_VALUE or clobber. 1441 DotDebugLocEntries.push_back(getDebugLocEntry(Asm, FLabel, SLabel, 1442 Begin)); 1443 } 1444 DotDebugLocEntries.push_back(DotDebugLocEntry()); 1445 } 1446 1447 // Collect info for variables that were optimized out. 1448 LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); 1449 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables(); 1450 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) { 1451 DIVariable DV(Variables.getElement(i)); 1452 if (!DV || !DV.isVariable() || !Processed.insert(DV)) 1453 continue; 1454 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext())) 1455 addScopeVariable(Scope, new DbgVariable(DV, NULL, this)); 1456 } 1457} 1458 1459// Return Label preceding the instruction. 1460MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) { 1461 MCSymbol *Label = LabelsBeforeInsn.lookup(MI); 1462 assert(Label && "Didn't insert label before instruction"); 1463 return Label; 1464} 1465 1466// Return Label immediately following the instruction. 1467MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) { 1468 return LabelsAfterInsn.lookup(MI); 1469} 1470 1471// Process beginning of an instruction. 1472void DwarfDebug::beginInstruction(const MachineInstr *MI) { 1473 // Check if source location changes, but ignore DBG_VALUE locations. 1474 if (!MI->isDebugValue()) { 1475 DebugLoc DL = MI->getDebugLoc(); 1476 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) { 1477 unsigned Flags = 0; 1478 PrevInstLoc = DL; 1479 if (DL == PrologEndLoc) { 1480 Flags |= DWARF2_FLAG_PROLOGUE_END; 1481 PrologEndLoc = DebugLoc(); 1482 } 1483 if (PrologEndLoc.isUnknown()) 1484 Flags |= DWARF2_FLAG_IS_STMT; 1485 1486 if (!DL.isUnknown()) { 1487 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext()); 1488 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags); 1489 } else 1490 recordSourceLine(0, 0, 0, 0); 1491 } 1492 } 1493 1494 // Insert labels where requested. 1495 DenseMap<const MachineInstr*, MCSymbol*>::iterator I = 1496 LabelsBeforeInsn.find(MI); 1497 1498 // No label needed. 1499 if (I == LabelsBeforeInsn.end()) 1500 return; 1501 1502 // Label already assigned. 1503 if (I->second) 1504 return; 1505 1506 if (!PrevLabel) { 1507 PrevLabel = MMI->getContext().CreateTempSymbol(); 1508 Asm->OutStreamer.EmitLabel(PrevLabel); 1509 } 1510 I->second = PrevLabel; 1511} 1512 1513// Process end of an instruction. 1514void DwarfDebug::endInstruction(const MachineInstr *MI) { 1515 // Don't create a new label after DBG_VALUE instructions. 1516 // They don't generate code. 1517 if (!MI->isDebugValue()) 1518 PrevLabel = 0; 1519 1520 DenseMap<const MachineInstr*, MCSymbol*>::iterator I = 1521 LabelsAfterInsn.find(MI); 1522 1523 // No label needed. 1524 if (I == LabelsAfterInsn.end()) 1525 return; 1526 1527 // Label already assigned. 1528 if (I->second) 1529 return; 1530 1531 // We need a label after this instruction. 1532 if (!PrevLabel) { 1533 PrevLabel = MMI->getContext().CreateTempSymbol(); 1534 Asm->OutStreamer.EmitLabel(PrevLabel); 1535 } 1536 I->second = PrevLabel; 1537} 1538 1539// Each LexicalScope has first instruction and last instruction to mark 1540// beginning and end of a scope respectively. Create an inverse map that list 1541// scopes starts (and ends) with an instruction. One instruction may start (or 1542// end) multiple scopes. Ignore scopes that are not reachable. 1543void DwarfDebug::identifyScopeMarkers() { 1544 SmallVector<LexicalScope *, 4> WorkList; 1545 WorkList.push_back(LScopes.getCurrentFunctionScope()); 1546 while (!WorkList.empty()) { 1547 LexicalScope *S = WorkList.pop_back_val(); 1548 1549 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren(); 1550 if (!Children.empty()) 1551 for (SmallVectorImpl<LexicalScope *>::const_iterator SI = Children.begin(), 1552 SE = Children.end(); SI != SE; ++SI) 1553 WorkList.push_back(*SI); 1554 1555 if (S->isAbstractScope()) 1556 continue; 1557 1558 const SmallVectorImpl<InsnRange> &Ranges = S->getRanges(); 1559 if (Ranges.empty()) 1560 continue; 1561 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 1562 RE = Ranges.end(); RI != RE; ++RI) { 1563 assert(RI->first && "InsnRange does not have first instruction!"); 1564 assert(RI->second && "InsnRange does not have second instruction!"); 1565 requestLabelBeforeInsn(RI->first); 1566 requestLabelAfterInsn(RI->second); 1567 } 1568 } 1569} 1570 1571// Get MDNode for DebugLoc's scope. 1572static MDNode *getScopeNode(DebugLoc DL, const LLVMContext &Ctx) { 1573 if (MDNode *InlinedAt = DL.getInlinedAt(Ctx)) 1574 return getScopeNode(DebugLoc::getFromDILocation(InlinedAt), Ctx); 1575 return DL.getScope(Ctx); 1576} 1577 1578// Walk up the scope chain of given debug loc and find line number info 1579// for the function. 1580static DebugLoc getFnDebugLoc(DebugLoc DL, const LLVMContext &Ctx) { 1581 const MDNode *Scope = getScopeNode(DL, Ctx); 1582 DISubprogram SP = getDISubprogram(Scope); 1583 if (SP.isSubprogram()) { 1584 // Check for number of operands since the compatibility is 1585 // cheap here. 1586 if (SP->getNumOperands() > 19) 1587 return DebugLoc::get(SP.getScopeLineNumber(), 0, SP); 1588 else 1589 return DebugLoc::get(SP.getLineNumber(), 0, SP); 1590 } 1591 1592 return DebugLoc(); 1593} 1594 1595// Gather pre-function debug information. Assumes being called immediately 1596// after the function entry point has been emitted. 1597void DwarfDebug::beginFunction(const MachineFunction *MF) { 1598 if (!MMI->hasDebugInfo()) return; 1599 LScopes.initialize(*MF); 1600 if (LScopes.empty()) return; 1601 identifyScopeMarkers(); 1602 1603 // Set DwarfCompileUnitID in MCContext to the Compile Unit this function 1604 // belongs to. 1605 LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); 1606 CompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode()); 1607 assert(TheCU && "Unable to find compile unit!"); 1608 if (Asm->TM.hasMCUseLoc() && Asm->OutStreamer.hasRawTextSupport()) 1609 // Use a single line table if we are using .loc and generating assembly. 1610 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0); 1611 else 1612 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID()); 1613 1614 FunctionBeginSym = Asm->GetTempSymbol("func_begin", 1615 Asm->getFunctionNumber()); 1616 // Assumes in correct section after the entry point. 1617 Asm->OutStreamer.EmitLabel(FunctionBeginSym); 1618 1619 assert(UserVariables.empty() && DbgValues.empty() && "Maps weren't cleaned"); 1620 1621 const TargetRegisterInfo *TRI = Asm->TM.getRegisterInfo(); 1622 // LiveUserVar - Map physreg numbers to the MDNode they contain. 1623 std::vector<const MDNode*> LiveUserVar(TRI->getNumRegs()); 1624 1625 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end(); 1626 I != E; ++I) { 1627 bool AtBlockEntry = true; 1628 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end(); 1629 II != IE; ++II) { 1630 const MachineInstr *MI = II; 1631 1632 if (MI->isDebugValue()) { 1633 assert(MI->getNumOperands() > 1 && "Invalid machine instruction!"); 1634 1635 // Keep track of user variables. 1636 const MDNode *Var = 1637 MI->getOperand(MI->getNumOperands() - 1).getMetadata(); 1638 1639 // Variable is in a register, we need to check for clobbers. 1640 if (isDbgValueInDefinedReg(MI)) 1641 LiveUserVar[MI->getOperand(0).getReg()] = Var; 1642 1643 // Check the history of this variable. 1644 SmallVectorImpl<const MachineInstr*> &History = DbgValues[Var]; 1645 if (History.empty()) { 1646 UserVariables.push_back(Var); 1647 // The first mention of a function argument gets the FunctionBeginSym 1648 // label, so arguments are visible when breaking at function entry. 1649 DIVariable DV(Var); 1650 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable && 1651 DISubprogram(getDISubprogram(DV.getContext())) 1652 .describes(MF->getFunction())) 1653 LabelsBeforeInsn[MI] = FunctionBeginSym; 1654 } else { 1655 // We have seen this variable before. Try to coalesce DBG_VALUEs. 1656 const MachineInstr *Prev = History.back(); 1657 if (Prev->isDebugValue()) { 1658 // Coalesce identical entries at the end of History. 1659 if (History.size() >= 2 && 1660 Prev->isIdenticalTo(History[History.size() - 2])) { 1661 DEBUG(dbgs() << "Coalescing identical DBG_VALUE entries:\n" 1662 << "\t" << *Prev 1663 << "\t" << *History[History.size() - 2] << "\n"); 1664 History.pop_back(); 1665 } 1666 1667 // Terminate old register assignments that don't reach MI; 1668 MachineFunction::const_iterator PrevMBB = Prev->getParent(); 1669 if (PrevMBB != I && (!AtBlockEntry || llvm::next(PrevMBB) != I) && 1670 isDbgValueInDefinedReg(Prev)) { 1671 // Previous register assignment needs to terminate at the end of 1672 // its basic block. 1673 MachineBasicBlock::const_iterator LastMI = 1674 PrevMBB->getLastNonDebugInstr(); 1675 if (LastMI == PrevMBB->end()) { 1676 // Drop DBG_VALUE for empty range. 1677 DEBUG(dbgs() << "Dropping DBG_VALUE for empty range:\n" 1678 << "\t" << *Prev << "\n"); 1679 History.pop_back(); 1680 } else if (llvm::next(PrevMBB) != PrevMBB->getParent()->end()) 1681 // Terminate after LastMI. 1682 History.push_back(LastMI); 1683 } 1684 } 1685 } 1686 History.push_back(MI); 1687 } else { 1688 // Not a DBG_VALUE instruction. 1689 if (!MI->isLabel()) 1690 AtBlockEntry = false; 1691 1692 // First known non-DBG_VALUE and non-frame setup location marks 1693 // the beginning of the function body. 1694 if (!MI->getFlag(MachineInstr::FrameSetup) && 1695 (PrologEndLoc.isUnknown() && !MI->getDebugLoc().isUnknown())) 1696 PrologEndLoc = MI->getDebugLoc(); 1697 1698 // Check if the instruction clobbers any registers with debug vars. 1699 for (MachineInstr::const_mop_iterator MOI = MI->operands_begin(), 1700 MOE = MI->operands_end(); MOI != MOE; ++MOI) { 1701 if (!MOI->isReg() || !MOI->isDef() || !MOI->getReg()) 1702 continue; 1703 for (MCRegAliasIterator AI(MOI->getReg(), TRI, true); 1704 AI.isValid(); ++AI) { 1705 unsigned Reg = *AI; 1706 const MDNode *Var = LiveUserVar[Reg]; 1707 if (!Var) 1708 continue; 1709 // Reg is now clobbered. 1710 LiveUserVar[Reg] = 0; 1711 1712 // Was MD last defined by a DBG_VALUE referring to Reg? 1713 DbgValueHistoryMap::iterator HistI = DbgValues.find(Var); 1714 if (HistI == DbgValues.end()) 1715 continue; 1716 SmallVectorImpl<const MachineInstr*> &History = HistI->second; 1717 if (History.empty()) 1718 continue; 1719 const MachineInstr *Prev = History.back(); 1720 // Sanity-check: Register assignments are terminated at the end of 1721 // their block. 1722 if (!Prev->isDebugValue() || Prev->getParent() != MI->getParent()) 1723 continue; 1724 // Is the variable still in Reg? 1725 if (!isDbgValueInDefinedReg(Prev) || 1726 Prev->getOperand(0).getReg() != Reg) 1727 continue; 1728 // Var is clobbered. Make sure the next instruction gets a label. 1729 History.push_back(MI); 1730 } 1731 } 1732 } 1733 } 1734 } 1735 1736 for (DbgValueHistoryMap::iterator I = DbgValues.begin(), E = DbgValues.end(); 1737 I != E; ++I) { 1738 SmallVectorImpl<const MachineInstr*> &History = I->second; 1739 if (History.empty()) 1740 continue; 1741 1742 // Make sure the final register assignments are terminated. 1743 const MachineInstr *Prev = History.back(); 1744 if (Prev->isDebugValue() && isDbgValueInDefinedReg(Prev)) { 1745 const MachineBasicBlock *PrevMBB = Prev->getParent(); 1746 MachineBasicBlock::const_iterator LastMI = 1747 PrevMBB->getLastNonDebugInstr(); 1748 if (LastMI == PrevMBB->end()) 1749 // Drop DBG_VALUE for empty range. 1750 History.pop_back(); 1751 else if (PrevMBB != &PrevMBB->getParent()->back()) { 1752 // Terminate after LastMI. 1753 History.push_back(LastMI); 1754 } 1755 } 1756 // Request labels for the full history. 1757 for (unsigned i = 0, e = History.size(); i != e; ++i) { 1758 const MachineInstr *MI = History[i]; 1759 if (MI->isDebugValue()) 1760 requestLabelBeforeInsn(MI); 1761 else 1762 requestLabelAfterInsn(MI); 1763 } 1764 } 1765 1766 PrevInstLoc = DebugLoc(); 1767 PrevLabel = FunctionBeginSym; 1768 1769 // Record beginning of function. 1770 if (!PrologEndLoc.isUnknown()) { 1771 DebugLoc FnStartDL = getFnDebugLoc(PrologEndLoc, 1772 MF->getFunction()->getContext()); 1773 recordSourceLine(FnStartDL.getLine(), FnStartDL.getCol(), 1774 FnStartDL.getScope(MF->getFunction()->getContext()), 1775 // We'd like to list the prologue as "not statements" but GDB behaves 1776 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing. 1777 DWARF2_FLAG_IS_STMT); 1778 } 1779} 1780 1781void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) { 1782 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS]; 1783 DIVariable DV = Var->getVariable(); 1784 // Variables with positive arg numbers are parameters. 1785 if (unsigned ArgNum = DV.getArgNumber()) { 1786 // Keep all parameters in order at the start of the variable list to ensure 1787 // function types are correct (no out-of-order parameters) 1788 // 1789 // This could be improved by only doing it for optimized builds (unoptimized 1790 // builds have the right order to begin with), searching from the back (this 1791 // would catch the unoptimized case quickly), or doing a binary search 1792 // rather than linear search. 1793 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin(); 1794 while (I != Vars.end()) { 1795 unsigned CurNum = (*I)->getVariable().getArgNumber(); 1796 // A local (non-parameter) variable has been found, insert immediately 1797 // before it. 1798 if (CurNum == 0) 1799 break; 1800 // A later indexed parameter has been found, insert immediately before it. 1801 if (CurNum > ArgNum) 1802 break; 1803 ++I; 1804 } 1805 Vars.insert(I, Var); 1806 return; 1807 } 1808 1809 Vars.push_back(Var); 1810} 1811 1812// Gather and emit post-function debug information. 1813void DwarfDebug::endFunction(const MachineFunction *MF) { 1814 if (!MMI->hasDebugInfo() || LScopes.empty()) return; 1815 1816 // Define end label for subprogram. 1817 FunctionEndSym = Asm->GetTempSymbol("func_end", 1818 Asm->getFunctionNumber()); 1819 // Assumes in correct section after the entry point. 1820 Asm->OutStreamer.EmitLabel(FunctionEndSym); 1821 // Set DwarfCompileUnitID in MCContext to default value. 1822 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0); 1823 1824 SmallPtrSet<const MDNode *, 16> ProcessedVars; 1825 collectVariableInfo(MF, ProcessedVars); 1826 1827 LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); 1828 CompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode()); 1829 assert(TheCU && "Unable to find compile unit!"); 1830 1831 // Construct abstract scopes. 1832 ArrayRef<LexicalScope *> AList = LScopes.getAbstractScopesList(); 1833 for (unsigned i = 0, e = AList.size(); i != e; ++i) { 1834 LexicalScope *AScope = AList[i]; 1835 DISubprogram SP(AScope->getScopeNode()); 1836 if (SP.isSubprogram()) { 1837 // Collect info for variables that were optimized out. 1838 DIArray Variables = SP.getVariables(); 1839 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) { 1840 DIVariable DV(Variables.getElement(i)); 1841 if (!DV || !DV.isVariable() || !ProcessedVars.insert(DV)) 1842 continue; 1843 // Check that DbgVariable for DV wasn't created earlier, when 1844 // findAbstractVariable() was called for inlined instance of DV. 1845 LLVMContext &Ctx = DV->getContext(); 1846 DIVariable CleanDV = cleanseInlinedVariable(DV, Ctx); 1847 if (AbstractVariables.lookup(CleanDV)) 1848 continue; 1849 if (LexicalScope *Scope = LScopes.findAbstractScope(DV.getContext())) 1850 addScopeVariable(Scope, new DbgVariable(DV, NULL, this)); 1851 } 1852 } 1853 if (ProcessedSPNodes.count(AScope->getScopeNode()) == 0) 1854 constructScopeDIE(TheCU, AScope); 1855 } 1856 1857 DIE *CurFnDIE = constructScopeDIE(TheCU, FnScope); 1858 1859 if (!MF->getTarget().Options.DisableFramePointerElim(*MF)) 1860 TheCU->addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr); 1861 1862 // Clear debug info 1863 for (ScopeVariablesMap::iterator 1864 I = ScopeVariables.begin(), E = ScopeVariables.end(); I != E; ++I) 1865 DeleteContainerPointers(I->second); 1866 ScopeVariables.clear(); 1867 DeleteContainerPointers(CurrentFnArguments); 1868 UserVariables.clear(); 1869 DbgValues.clear(); 1870 AbstractVariables.clear(); 1871 LabelsBeforeInsn.clear(); 1872 LabelsAfterInsn.clear(); 1873 PrevLabel = NULL; 1874} 1875 1876// Register a source line with debug info. Returns the unique label that was 1877// emitted and which provides correspondence to the source line list. 1878void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S, 1879 unsigned Flags) { 1880 StringRef Fn; 1881 StringRef Dir; 1882 unsigned Src = 1; 1883 if (S) { 1884 DIDescriptor Scope(S); 1885 1886 if (Scope.isCompileUnit()) { 1887 DICompileUnit CU(S); 1888 Fn = CU.getFilename(); 1889 Dir = CU.getDirectory(); 1890 } else if (Scope.isFile()) { 1891 DIFile F(S); 1892 Fn = F.getFilename(); 1893 Dir = F.getDirectory(); 1894 } else if (Scope.isSubprogram()) { 1895 DISubprogram SP(S); 1896 Fn = SP.getFilename(); 1897 Dir = SP.getDirectory(); 1898 } else if (Scope.isLexicalBlockFile()) { 1899 DILexicalBlockFile DBF(S); 1900 Fn = DBF.getFilename(); 1901 Dir = DBF.getDirectory(); 1902 } else if (Scope.isLexicalBlock()) { 1903 DILexicalBlock DB(S); 1904 Fn = DB.getFilename(); 1905 Dir = DB.getDirectory(); 1906 } else 1907 llvm_unreachable("Unexpected scope info"); 1908 1909 Src = getOrCreateSourceID(Fn, Dir, 1910 Asm->OutStreamer.getContext().getDwarfCompileUnitID()); 1911 } 1912 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0, 0, Fn); 1913} 1914 1915//===----------------------------------------------------------------------===// 1916// Emit Methods 1917//===----------------------------------------------------------------------===// 1918 1919// Compute the size and offset of a DIE. The offset is relative to start of the 1920// CU. It returns the offset after laying out the DIE. 1921unsigned 1922DwarfUnits::computeSizeAndOffset(DIE *Die, unsigned Offset) { 1923 // Get the children. 1924 const std::vector<DIE *> &Children = Die->getChildren(); 1925 1926 // Record the abbreviation. 1927 assignAbbrevNumber(Die->getAbbrev()); 1928 1929 // Get the abbreviation for this DIE. 1930 unsigned AbbrevNumber = Die->getAbbrevNumber(); 1931 const DIEAbbrev *Abbrev = Abbreviations[AbbrevNumber - 1]; 1932 1933 // Set DIE offset 1934 Die->setOffset(Offset); 1935 1936 // Start the size with the size of abbreviation code. 1937 Offset += MCAsmInfo::getULEB128Size(AbbrevNumber); 1938 1939 const SmallVectorImpl<DIEValue*> &Values = Die->getValues(); 1940 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev->getData(); 1941 1942 // Size the DIE attribute values. 1943 for (unsigned i = 0, N = Values.size(); i < N; ++i) 1944 // Size attribute value. 1945 Offset += Values[i]->SizeOf(Asm, AbbrevData[i].getForm()); 1946 1947 // Size the DIE children if any. 1948 if (!Children.empty()) { 1949 assert(Abbrev->getChildrenFlag() == dwarf::DW_CHILDREN_yes && 1950 "Children flag not set"); 1951 1952 for (unsigned j = 0, M = Children.size(); j < M; ++j) 1953 Offset = computeSizeAndOffset(Children[j], Offset); 1954 1955 // End of children marker. 1956 Offset += sizeof(int8_t); 1957 } 1958 1959 Die->setSize(Offset - Die->getOffset()); 1960 return Offset; 1961} 1962 1963// Compute the size and offset for each DIE. 1964void DwarfUnits::computeSizeAndOffsets() { 1965 // Offset from the first CU in the debug info section is 0 initially. 1966 unsigned SecOffset = 0; 1967 1968 // Iterate over each compile unit and set the size and offsets for each 1969 // DIE within each compile unit. All offsets are CU relative. 1970 for (SmallVectorImpl<CompileUnit *>::iterator I = CUs.begin(), 1971 E = CUs.end(); I != E; ++I) { 1972 (*I)->setDebugInfoOffset(SecOffset); 1973 1974 // CU-relative offset is reset to 0 here. 1975 unsigned Offset = sizeof(int32_t) + // Length of Unit Info 1976 (*I)->getHeaderSize(); // Unit-specific headers 1977 1978 // EndOffset here is CU-relative, after laying out 1979 // all of the CU DIE. 1980 unsigned EndOffset = computeSizeAndOffset((*I)->getCUDie(), Offset); 1981 SecOffset += EndOffset; 1982 } 1983} 1984 1985// Emit initial Dwarf sections with a label at the start of each one. 1986void DwarfDebug::emitSectionLabels() { 1987 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); 1988 1989 // Dwarf sections base addresses. 1990 DwarfInfoSectionSym = 1991 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info"); 1992 DwarfAbbrevSectionSym = 1993 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev"); 1994 if (useSplitDwarf()) 1995 DwarfAbbrevDWOSectionSym = 1996 emitSectionSym(Asm, TLOF.getDwarfAbbrevDWOSection(), 1997 "section_abbrev_dwo"); 1998 emitSectionSym(Asm, TLOF.getDwarfARangesSection()); 1999 2000 if (const MCSection *MacroInfo = TLOF.getDwarfMacroInfoSection()) 2001 emitSectionSym(Asm, MacroInfo); 2002 2003 DwarfLineSectionSym = 2004 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line"); 2005 emitSectionSym(Asm, TLOF.getDwarfLocSection()); 2006 if (GenerateGnuPubSections) { 2007 DwarfGnuPubNamesSectionSym = 2008 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection()); 2009 DwarfGnuPubTypesSectionSym = 2010 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection()); 2011 } else if (HasDwarfPubSections) { 2012 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection()); 2013 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection()); 2014 } 2015 2016 DwarfStrSectionSym = 2017 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string"); 2018 if (useSplitDwarf()) { 2019 DwarfStrDWOSectionSym = 2020 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string"); 2021 DwarfAddrSectionSym = 2022 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec"); 2023 } 2024 DwarfDebugRangeSectionSym = emitSectionSym(Asm, TLOF.getDwarfRangesSection(), 2025 "debug_range"); 2026 2027 DwarfDebugLocSectionSym = emitSectionSym(Asm, TLOF.getDwarfLocSection(), 2028 "section_debug_loc"); 2029 2030 TextSectionSym = emitSectionSym(Asm, TLOF.getTextSection(), "text_begin"); 2031 emitSectionSym(Asm, TLOF.getDataSection()); 2032} 2033 2034// Recursively emits a debug information entry. 2035void DwarfDebug::emitDIE(DIE *Die, ArrayRef<DIEAbbrev *> Abbrevs) { 2036 // Get the abbreviation for this DIE. 2037 unsigned AbbrevNumber = Die->getAbbrevNumber(); 2038 const DIEAbbrev *Abbrev = Abbrevs[AbbrevNumber - 1]; 2039 2040 // Emit the code (index) for the abbreviation. 2041 if (Asm->isVerbose()) 2042 Asm->OutStreamer.AddComment("Abbrev [" + Twine(AbbrevNumber) + "] 0x" + 2043 Twine::utohexstr(Die->getOffset()) + ":0x" + 2044 Twine::utohexstr(Die->getSize()) + " " + 2045 dwarf::TagString(Abbrev->getTag())); 2046 Asm->EmitULEB128(AbbrevNumber); 2047 2048 const SmallVectorImpl<DIEValue*> &Values = Die->getValues(); 2049 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev->getData(); 2050 2051 // Emit the DIE attribute values. 2052 for (unsigned i = 0, N = Values.size(); i < N; ++i) { 2053 dwarf::Attribute Attr = AbbrevData[i].getAttribute(); 2054 dwarf::Form Form = AbbrevData[i].getForm(); 2055 assert(Form && "Too many attributes for DIE (check abbreviation)"); 2056 2057 if (Asm->isVerbose()) 2058 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr)); 2059 2060 switch (Attr) { 2061 case dwarf::DW_AT_abstract_origin: 2062 case dwarf::DW_AT_type: 2063 case dwarf::DW_AT_friend: 2064 case dwarf::DW_AT_specification: 2065 case dwarf::DW_AT_import: 2066 case dwarf::DW_AT_containing_type: { 2067 DIEEntry *E = cast<DIEEntry>(Values[i]); 2068 DIE *Origin = E->getEntry(); 2069 unsigned Addr = Origin->getOffset(); 2070 if (Form == dwarf::DW_FORM_ref_addr) { 2071 assert(!useSplitDwarf() && "TODO: dwo files can't have relocations."); 2072 // For DW_FORM_ref_addr, output the offset from beginning of debug info 2073 // section. Origin->getOffset() returns the offset from start of the 2074 // compile unit. 2075 CompileUnit *CU = CUDieMap.lookup(Origin->getCompileUnit()); 2076 assert(CU && "CUDie should belong to a CU."); 2077 Addr += CU->getDebugInfoOffset(); 2078 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2079 Asm->EmitLabelPlusOffset(DwarfInfoSectionSym, Addr, 2080 DIEEntry::getRefAddrSize(Asm)); 2081 else 2082 Asm->EmitLabelOffsetDifference(DwarfInfoSectionSym, Addr, 2083 DwarfInfoSectionSym, 2084 DIEEntry::getRefAddrSize(Asm)); 2085 } else { 2086 Asm->EmitInt32(Addr); 2087 } 2088 break; 2089 } 2090 case dwarf::DW_AT_ranges: { 2091 // DW_AT_range Value encodes offset in debug_range section. 2092 DIEInteger *V = cast<DIEInteger>(Values[i]); 2093 2094 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) { 2095 Asm->EmitLabelPlusOffset(DwarfDebugRangeSectionSym, 2096 V->getValue(), 2097 4); 2098 } else { 2099 Asm->EmitLabelOffsetDifference(DwarfDebugRangeSectionSym, 2100 V->getValue(), 2101 DwarfDebugRangeSectionSym, 2102 4); 2103 } 2104 break; 2105 } 2106 case dwarf::DW_AT_location: { 2107 if (DIELabel *L = dyn_cast<DIELabel>(Values[i])) { 2108 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2109 Asm->EmitLabelReference(L->getValue(), 4); 2110 else 2111 Asm->EmitLabelDifference(L->getValue(), DwarfDebugLocSectionSym, 4); 2112 } else { 2113 Values[i]->EmitValue(Asm, Form); 2114 } 2115 break; 2116 } 2117 case dwarf::DW_AT_accessibility: { 2118 if (Asm->isVerbose()) { 2119 DIEInteger *V = cast<DIEInteger>(Values[i]); 2120 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(V->getValue())); 2121 } 2122 Values[i]->EmitValue(Asm, Form); 2123 break; 2124 } 2125 default: 2126 // Emit an attribute using the defined form. 2127 Values[i]->EmitValue(Asm, Form); 2128 break; 2129 } 2130 } 2131 2132 // Emit the DIE children if any. 2133 if (Abbrev->getChildrenFlag() == dwarf::DW_CHILDREN_yes) { 2134 const std::vector<DIE *> &Children = Die->getChildren(); 2135 2136 for (unsigned j = 0, M = Children.size(); j < M; ++j) 2137 emitDIE(Children[j], Abbrevs); 2138 2139 if (Asm->isVerbose()) 2140 Asm->OutStreamer.AddComment("End Of Children Mark"); 2141 Asm->EmitInt8(0); 2142 } 2143} 2144 2145// Emit the various dwarf units to the unit section USection with 2146// the abbreviations going into ASection. 2147void DwarfUnits::emitUnits(DwarfDebug *DD, 2148 const MCSection *USection, 2149 const MCSection *ASection, 2150 const MCSymbol *ASectionSym) { 2151 Asm->OutStreamer.SwitchSection(USection); 2152 for (SmallVectorImpl<CompileUnit *>::iterator I = CUs.begin(), 2153 E = CUs.end(); I != E; ++I) { 2154 CompileUnit *TheCU = *I; 2155 DIE *Die = TheCU->getCUDie(); 2156 2157 // Emit the compile units header. 2158 Asm->OutStreamer 2159 .EmitLabel(Asm->GetTempSymbol(USection->getLabelBeginName(), 2160 TheCU->getUniqueID())); 2161 2162 // Emit size of content not including length itself 2163 Asm->OutStreamer.AddComment("Length of Unit"); 2164 Asm->EmitInt32(TheCU->getHeaderSize() + Die->getSize()); 2165 2166 TheCU->emitHeader(ASection, ASectionSym); 2167 2168 DD->emitDIE(Die, Abbreviations); 2169 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol(USection->getLabelEndName(), 2170 TheCU->getUniqueID())); 2171 } 2172} 2173 2174// Emit the debug info section. 2175void DwarfDebug::emitDebugInfo() { 2176 DwarfUnits &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; 2177 2178 Holder.emitUnits(this, Asm->getObjFileLowering().getDwarfInfoSection(), 2179 Asm->getObjFileLowering().getDwarfAbbrevSection(), 2180 DwarfAbbrevSectionSym); 2181} 2182 2183// Emit the abbreviation section. 2184void DwarfDebug::emitAbbreviations() { 2185 if (!useSplitDwarf()) 2186 emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection(), 2187 &Abbreviations); 2188 else 2189 emitSkeletonAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection()); 2190} 2191 2192void DwarfDebug::emitAbbrevs(const MCSection *Section, 2193 std::vector<DIEAbbrev *> *Abbrevs) { 2194 // Check to see if it is worth the effort. 2195 if (!Abbrevs->empty()) { 2196 // Start the debug abbrev section. 2197 Asm->OutStreamer.SwitchSection(Section); 2198 2199 MCSymbol *Begin = Asm->GetTempSymbol(Section->getLabelBeginName()); 2200 Asm->OutStreamer.EmitLabel(Begin); 2201 2202 // For each abbrevation. 2203 for (unsigned i = 0, N = Abbrevs->size(); i < N; ++i) { 2204 // Get abbreviation data 2205 const DIEAbbrev *Abbrev = Abbrevs->at(i); 2206 2207 // Emit the abbrevations code (base 1 index.) 2208 Asm->EmitULEB128(Abbrev->getNumber(), "Abbreviation Code"); 2209 2210 // Emit the abbreviations data. 2211 Abbrev->Emit(Asm); 2212 } 2213 2214 // Mark end of abbreviations. 2215 Asm->EmitULEB128(0, "EOM(3)"); 2216 2217 MCSymbol *End = Asm->GetTempSymbol(Section->getLabelEndName()); 2218 Asm->OutStreamer.EmitLabel(End); 2219 } 2220} 2221 2222// Emit the last address of the section and the end of the line matrix. 2223void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) { 2224 // Define last address of section. 2225 Asm->OutStreamer.AddComment("Extended Op"); 2226 Asm->EmitInt8(0); 2227 2228 Asm->OutStreamer.AddComment("Op size"); 2229 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1); 2230 Asm->OutStreamer.AddComment("DW_LNE_set_address"); 2231 Asm->EmitInt8(dwarf::DW_LNE_set_address); 2232 2233 Asm->OutStreamer.AddComment("Section end label"); 2234 2235 Asm->OutStreamer.EmitSymbolValue(Asm->GetTempSymbol("section_end",SectionEnd), 2236 Asm->getDataLayout().getPointerSize()); 2237 2238 // Mark end of matrix. 2239 Asm->OutStreamer.AddComment("DW_LNE_end_sequence"); 2240 Asm->EmitInt8(0); 2241 Asm->EmitInt8(1); 2242 Asm->EmitInt8(1); 2243} 2244 2245// Emit visible names into a hashed accelerator table section. 2246void DwarfDebug::emitAccelNames() { 2247 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2248 dwarf::DW_FORM_data4)); 2249 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2250 E = CUMap.end(); I != E; ++I) { 2251 CompileUnit *TheCU = I->second; 2252 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelNames(); 2253 for (StringMap<std::vector<DIE*> >::const_iterator 2254 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2255 StringRef Name = GI->getKey(); 2256 const std::vector<DIE *> &Entities = GI->second; 2257 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2258 DE = Entities.end(); DI != DE; ++DI) 2259 AT.AddName(Name, (*DI)); 2260 } 2261 } 2262 2263 AT.FinalizeTable(Asm, "Names"); 2264 Asm->OutStreamer.SwitchSection( 2265 Asm->getObjFileLowering().getDwarfAccelNamesSection()); 2266 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin"); 2267 Asm->OutStreamer.EmitLabel(SectionBegin); 2268 2269 // Emit the full data. 2270 AT.Emit(Asm, SectionBegin, &InfoHolder); 2271} 2272 2273// Emit objective C classes and categories into a hashed accelerator table 2274// section. 2275void DwarfDebug::emitAccelObjC() { 2276 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2277 dwarf::DW_FORM_data4)); 2278 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2279 E = CUMap.end(); I != E; ++I) { 2280 CompileUnit *TheCU = I->second; 2281 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelObjC(); 2282 for (StringMap<std::vector<DIE*> >::const_iterator 2283 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2284 StringRef Name = GI->getKey(); 2285 const std::vector<DIE *> &Entities = GI->second; 2286 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2287 DE = Entities.end(); DI != DE; ++DI) 2288 AT.AddName(Name, (*DI)); 2289 } 2290 } 2291 2292 AT.FinalizeTable(Asm, "ObjC"); 2293 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2294 .getDwarfAccelObjCSection()); 2295 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin"); 2296 Asm->OutStreamer.EmitLabel(SectionBegin); 2297 2298 // Emit the full data. 2299 AT.Emit(Asm, SectionBegin, &InfoHolder); 2300} 2301 2302// Emit namespace dies into a hashed accelerator table. 2303void DwarfDebug::emitAccelNamespaces() { 2304 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2305 dwarf::DW_FORM_data4)); 2306 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2307 E = CUMap.end(); I != E; ++I) { 2308 CompileUnit *TheCU = I->second; 2309 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelNamespace(); 2310 for (StringMap<std::vector<DIE*> >::const_iterator 2311 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2312 StringRef Name = GI->getKey(); 2313 const std::vector<DIE *> &Entities = GI->second; 2314 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2315 DE = Entities.end(); DI != DE; ++DI) 2316 AT.AddName(Name, (*DI)); 2317 } 2318 } 2319 2320 AT.FinalizeTable(Asm, "namespac"); 2321 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2322 .getDwarfAccelNamespaceSection()); 2323 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin"); 2324 Asm->OutStreamer.EmitLabel(SectionBegin); 2325 2326 // Emit the full data. 2327 AT.Emit(Asm, SectionBegin, &InfoHolder); 2328} 2329 2330// Emit type dies into a hashed accelerator table. 2331void DwarfDebug::emitAccelTypes() { 2332 std::vector<DwarfAccelTable::Atom> Atoms; 2333 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2334 dwarf::DW_FORM_data4)); 2335 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, 2336 dwarf::DW_FORM_data2)); 2337 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, 2338 dwarf::DW_FORM_data1)); 2339 DwarfAccelTable AT(Atoms); 2340 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2341 E = CUMap.end(); I != E; ++I) { 2342 CompileUnit *TheCU = I->second; 2343 const StringMap<std::vector<std::pair<DIE*, unsigned > > > &Names 2344 = TheCU->getAccelTypes(); 2345 for (StringMap<std::vector<std::pair<DIE*, unsigned> > >::const_iterator 2346 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2347 StringRef Name = GI->getKey(); 2348 const std::vector<std::pair<DIE *, unsigned> > &Entities = GI->second; 2349 for (std::vector<std::pair<DIE *, unsigned> >::const_iterator DI 2350 = Entities.begin(), DE = Entities.end(); DI !=DE; ++DI) 2351 AT.AddName(Name, (*DI).first, (*DI).second); 2352 } 2353 } 2354 2355 AT.FinalizeTable(Asm, "types"); 2356 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2357 .getDwarfAccelTypesSection()); 2358 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin"); 2359 Asm->OutStreamer.EmitLabel(SectionBegin); 2360 2361 // Emit the full data. 2362 AT.Emit(Asm, SectionBegin, &InfoHolder); 2363} 2364 2365// Public name handling. 2366// The format for the various pubnames: 2367// 2368// dwarf pubnames - offset/name pairs where the offset is the offset into the CU 2369// for the DIE that is named. 2370// 2371// gnu pubnames - offset/index value/name tuples where the offset is the offset 2372// into the CU and the index value is computed according to the type of value 2373// for the DIE that is named. 2374// 2375// For type units the offset is the offset of the skeleton DIE. For split dwarf 2376// it's the offset within the debug_info/debug_types dwo section, however, the 2377// reference in the pubname header doesn't change. 2378 2379/// computeIndexValue - Compute the gdb index value for the DIE and CU. 2380static dwarf::PubIndexEntryDescriptor computeIndexValue(CompileUnit *CU, 2381 DIE *Die) { 2382 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC; 2383 2384 // We could have a specification DIE that has our most of our knowledge, 2385 // look for that now. 2386 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification); 2387 if (SpecVal) { 2388 DIE *SpecDIE = cast<DIEEntry>(SpecVal)->getEntry(); 2389 if (SpecDIE->findAttribute(dwarf::DW_AT_external)) 2390 Linkage = dwarf::GIEL_EXTERNAL; 2391 } else if (Die->findAttribute(dwarf::DW_AT_external)) 2392 Linkage = dwarf::GIEL_EXTERNAL; 2393 2394 switch (Die->getTag()) { 2395 case dwarf::DW_TAG_class_type: 2396 case dwarf::DW_TAG_structure_type: 2397 case dwarf::DW_TAG_union_type: 2398 case dwarf::DW_TAG_enumeration_type: 2399 return dwarf::PubIndexEntryDescriptor( 2400 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus 2401 ? dwarf::GIEL_STATIC 2402 : dwarf::GIEL_EXTERNAL); 2403 case dwarf::DW_TAG_typedef: 2404 case dwarf::DW_TAG_base_type: 2405 case dwarf::DW_TAG_subrange_type: 2406 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC); 2407 case dwarf::DW_TAG_namespace: 2408 return dwarf::GIEK_TYPE; 2409 case dwarf::DW_TAG_subprogram: 2410 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage); 2411 case dwarf::DW_TAG_constant: 2412 case dwarf::DW_TAG_variable: 2413 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage); 2414 case dwarf::DW_TAG_enumerator: 2415 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, 2416 dwarf::GIEL_STATIC); 2417 default: 2418 return dwarf::GIEK_NONE; 2419 } 2420} 2421 2422/// emitDebugPubNames - Emit visible names into a debug pubnames section. 2423/// 2424void DwarfDebug::emitDebugPubNames(bool GnuStyle) { 2425 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2426 const MCSection *PSec = 2427 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection() 2428 : Asm->getObjFileLowering().getDwarfPubNamesSection(); 2429 2430 typedef DenseMap<const MDNode*, CompileUnit*> CUMapType; 2431 for (CUMapType::iterator I = CUMap.begin(), E = CUMap.end(); I != E; ++I) { 2432 CompileUnit *TheCU = I->second; 2433 unsigned ID = TheCU->getUniqueID(); 2434 2435 // Start the dwarf pubnames section. 2436 Asm->OutStreamer.SwitchSection(PSec); 2437 2438 // Emit a label so we can reference the beginning of this pubname section. 2439 if (GnuStyle) 2440 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("gnu_pubnames", 2441 TheCU->getUniqueID())); 2442 2443 // Emit the header. 2444 Asm->OutStreamer.AddComment("Length of Public Names Info"); 2445 Asm->EmitLabelDifference(Asm->GetTempSymbol("pubnames_end", ID), 2446 Asm->GetTempSymbol("pubnames_begin", ID), 4); 2447 2448 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("pubnames_begin", ID)); 2449 2450 Asm->OutStreamer.AddComment("DWARF Version"); 2451 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION); 2452 2453 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info"); 2454 Asm->EmitSectionOffset(Asm->GetTempSymbol(ISec->getLabelBeginName(), ID), 2455 DwarfInfoSectionSym); 2456 2457 Asm->OutStreamer.AddComment("Compilation Unit Length"); 2458 Asm->EmitLabelDifference(Asm->GetTempSymbol(ISec->getLabelEndName(), ID), 2459 Asm->GetTempSymbol(ISec->getLabelBeginName(), ID), 2460 4); 2461 2462 // Emit the pubnames for this compilation unit. 2463 const StringMap<DIE*> &Globals = TheCU->getGlobalNames(); 2464 for (StringMap<DIE*>::const_iterator 2465 GI = Globals.begin(), GE = Globals.end(); GI != GE; ++GI) { 2466 const char *Name = GI->getKeyData(); 2467 DIE *Entity = GI->second; 2468 2469 Asm->OutStreamer.AddComment("DIE offset"); 2470 Asm->EmitInt32(Entity->getOffset()); 2471 2472 if (GnuStyle) { 2473 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheCU, Entity); 2474 Asm->OutStreamer.AddComment( 2475 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " + 2476 dwarf::GDBIndexEntryLinkageString(Desc.Linkage)); 2477 Asm->EmitInt8(Desc.toBits()); 2478 } 2479 2480 if (Asm->isVerbose()) 2481 Asm->OutStreamer.AddComment("External Name"); 2482 Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength()+1)); 2483 } 2484 2485 Asm->OutStreamer.AddComment("End Mark"); 2486 Asm->EmitInt32(0); 2487 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("pubnames_end", ID)); 2488 } 2489} 2490 2491void DwarfDebug::emitDebugPubTypes(bool GnuStyle) { 2492 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2493 const MCSection *PSec = 2494 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection() 2495 : Asm->getObjFileLowering().getDwarfPubTypesSection(); 2496 2497 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2498 E = CUMap.end(); 2499 I != E; ++I) { 2500 CompileUnit *TheCU = I->second; 2501 // Start the dwarf pubtypes section. 2502 Asm->OutStreamer.SwitchSection(PSec); 2503 2504 // Emit a label so we can reference the beginning of this pubtype section. 2505 if (GnuStyle) 2506 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("gnu_pubtypes", 2507 TheCU->getUniqueID())); 2508 2509 // Emit the header. 2510 Asm->OutStreamer.AddComment("Length of Public Types Info"); 2511 Asm->EmitLabelDifference( 2512 Asm->GetTempSymbol("pubtypes_end", TheCU->getUniqueID()), 2513 Asm->GetTempSymbol("pubtypes_begin", TheCU->getUniqueID()), 4); 2514 2515 Asm->OutStreamer.EmitLabel( 2516 Asm->GetTempSymbol("pubtypes_begin", TheCU->getUniqueID())); 2517 2518 if (Asm->isVerbose()) 2519 Asm->OutStreamer.AddComment("DWARF Version"); 2520 Asm->EmitInt16(dwarf::DW_PUBTYPES_VERSION); 2521 2522 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info"); 2523 Asm->EmitSectionOffset( 2524 Asm->GetTempSymbol(ISec->getLabelBeginName(), TheCU->getUniqueID()), 2525 DwarfInfoSectionSym); 2526 2527 Asm->OutStreamer.AddComment("Compilation Unit Length"); 2528 Asm->EmitLabelDifference( 2529 Asm->GetTempSymbol(ISec->getLabelEndName(), TheCU->getUniqueID()), 2530 Asm->GetTempSymbol(ISec->getLabelBeginName(), TheCU->getUniqueID()), 4); 2531 2532 // Emit the pubtypes. 2533 const StringMap<DIE *> &Globals = TheCU->getGlobalTypes(); 2534 for (StringMap<DIE *>::const_iterator GI = Globals.begin(), 2535 GE = Globals.end(); 2536 GI != GE; ++GI) { 2537 const char *Name = GI->getKeyData(); 2538 DIE *Entity = GI->second; 2539 2540 if (Asm->isVerbose()) 2541 Asm->OutStreamer.AddComment("DIE offset"); 2542 Asm->EmitInt32(Entity->getOffset()); 2543 2544 if (GnuStyle) { 2545 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheCU, Entity); 2546 Asm->OutStreamer.AddComment( 2547 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " + 2548 dwarf::GDBIndexEntryLinkageString(Desc.Linkage)); 2549 Asm->EmitInt8(Desc.toBits()); 2550 } 2551 2552 if (Asm->isVerbose()) 2553 Asm->OutStreamer.AddComment("External Name"); 2554 2555 // Emit the name with a terminating null byte. 2556 Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength() + 1)); 2557 } 2558 2559 Asm->OutStreamer.AddComment("End Mark"); 2560 Asm->EmitInt32(0); 2561 Asm->OutStreamer.EmitLabel( 2562 Asm->GetTempSymbol("pubtypes_end", TheCU->getUniqueID())); 2563 } 2564} 2565 2566// Emit strings into a string section. 2567void DwarfUnits::emitStrings(const MCSection *StrSection, 2568 const MCSection *OffsetSection = NULL, 2569 const MCSymbol *StrSecSym = NULL) { 2570 2571 if (StringPool.empty()) return; 2572 2573 // Start the dwarf str section. 2574 Asm->OutStreamer.SwitchSection(StrSection); 2575 2576 // Get all of the string pool entries and put them in an array by their ID so 2577 // we can sort them. 2578 SmallVector<std::pair<unsigned, 2579 StringMapEntry<std::pair<MCSymbol*, unsigned> >*>, 64> Entries; 2580 2581 for (StringMap<std::pair<MCSymbol*, unsigned> >::iterator 2582 I = StringPool.begin(), E = StringPool.end(); 2583 I != E; ++I) 2584 Entries.push_back(std::make_pair(I->second.second, &*I)); 2585 2586 array_pod_sort(Entries.begin(), Entries.end()); 2587 2588 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2589 // Emit a label for reference from debug information entries. 2590 Asm->OutStreamer.EmitLabel(Entries[i].second->getValue().first); 2591 2592 // Emit the string itself with a terminating null byte. 2593 Asm->OutStreamer.EmitBytes(StringRef(Entries[i].second->getKeyData(), 2594 Entries[i].second->getKeyLength()+1)); 2595 } 2596 2597 // If we've got an offset section go ahead and emit that now as well. 2598 if (OffsetSection) { 2599 Asm->OutStreamer.SwitchSection(OffsetSection); 2600 unsigned offset = 0; 2601 unsigned size = 4; // FIXME: DWARF64 is 8. 2602 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2603 Asm->OutStreamer.EmitIntValue(offset, size); 2604 offset += Entries[i].second->getKeyLength() + 1; 2605 } 2606 } 2607} 2608 2609// Emit strings into a string section. 2610void DwarfUnits::emitAddresses(const MCSection *AddrSection) { 2611 2612 if (AddressPool.empty()) return; 2613 2614 // Start the dwarf addr section. 2615 Asm->OutStreamer.SwitchSection(AddrSection); 2616 2617 // Order the address pool entries by ID 2618 SmallVector<const MCExpr *, 64> Entries(AddressPool.size()); 2619 2620 for (DenseMap<const MCExpr *, unsigned>::iterator I = AddressPool.begin(), 2621 E = AddressPool.end(); 2622 I != E; ++I) 2623 Entries[I->second] = I->first; 2624 2625 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2626 // Emit an expression for reference from debug information entries. 2627 if (const MCExpr *Expr = Entries[i]) 2628 Asm->OutStreamer.EmitValue(Expr, Asm->getDataLayout().getPointerSize()); 2629 else 2630 Asm->OutStreamer.EmitIntValue(0, Asm->getDataLayout().getPointerSize()); 2631 } 2632 2633} 2634 2635// Emit visible names into a debug str section. 2636void DwarfDebug::emitDebugStr() { 2637 DwarfUnits &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; 2638 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection()); 2639} 2640 2641// Emit locations into the debug loc section. 2642void DwarfDebug::emitDebugLoc() { 2643 if (DotDebugLocEntries.empty()) 2644 return; 2645 2646 for (SmallVectorImpl<DotDebugLocEntry>::iterator 2647 I = DotDebugLocEntries.begin(), E = DotDebugLocEntries.end(); 2648 I != E; ++I) { 2649 DotDebugLocEntry &Entry = *I; 2650 if (I + 1 != DotDebugLocEntries.end()) 2651 Entry.Merge(I+1); 2652 } 2653 2654 // Start the dwarf loc section. 2655 Asm->OutStreamer.SwitchSection( 2656 Asm->getObjFileLowering().getDwarfLocSection()); 2657 unsigned char Size = Asm->getDataLayout().getPointerSize(); 2658 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", 0)); 2659 unsigned index = 1; 2660 for (SmallVectorImpl<DotDebugLocEntry>::iterator 2661 I = DotDebugLocEntries.begin(), E = DotDebugLocEntries.end(); 2662 I != E; ++I, ++index) { 2663 DotDebugLocEntry &Entry = *I; 2664 if (Entry.isMerged()) continue; 2665 if (Entry.isEmpty()) { 2666 Asm->OutStreamer.EmitIntValue(0, Size); 2667 Asm->OutStreamer.EmitIntValue(0, Size); 2668 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", index)); 2669 } else { 2670 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size); 2671 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size); 2672 DIVariable DV(Entry.getVariable()); 2673 Asm->OutStreamer.AddComment("Loc expr size"); 2674 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol(); 2675 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol(); 2676 Asm->EmitLabelDifference(end, begin, 2); 2677 Asm->OutStreamer.EmitLabel(begin); 2678 if (Entry.isInt()) { 2679 DIBasicType BTy(DV.getType()); 2680 if (BTy.Verify() && 2681 (BTy.getEncoding() == dwarf::DW_ATE_signed 2682 || BTy.getEncoding() == dwarf::DW_ATE_signed_char)) { 2683 Asm->OutStreamer.AddComment("DW_OP_consts"); 2684 Asm->EmitInt8(dwarf::DW_OP_consts); 2685 Asm->EmitSLEB128(Entry.getInt()); 2686 } else { 2687 Asm->OutStreamer.AddComment("DW_OP_constu"); 2688 Asm->EmitInt8(dwarf::DW_OP_constu); 2689 Asm->EmitULEB128(Entry.getInt()); 2690 } 2691 } else if (Entry.isLocation()) { 2692 MachineLocation Loc = Entry.getLoc(); 2693 if (!DV.hasComplexAddress()) 2694 // Regular entry. 2695 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2696 else { 2697 // Complex address entry. 2698 unsigned N = DV.getNumAddrElements(); 2699 unsigned i = 0; 2700 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) { 2701 if (Loc.getOffset()) { 2702 i = 2; 2703 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2704 Asm->OutStreamer.AddComment("DW_OP_deref"); 2705 Asm->EmitInt8(dwarf::DW_OP_deref); 2706 Asm->OutStreamer.AddComment("DW_OP_plus_uconst"); 2707 Asm->EmitInt8(dwarf::DW_OP_plus_uconst); 2708 Asm->EmitSLEB128(DV.getAddrElement(1)); 2709 } else { 2710 // If first address element is OpPlus then emit 2711 // DW_OP_breg + Offset instead of DW_OP_reg + Offset. 2712 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1)); 2713 Asm->EmitDwarfRegOp(TLoc, DV.isIndirect()); 2714 i = 2; 2715 } 2716 } else { 2717 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2718 } 2719 2720 // Emit remaining complex address elements. 2721 for (; i < N; ++i) { 2722 uint64_t Element = DV.getAddrElement(i); 2723 if (Element == DIBuilder::OpPlus) { 2724 Asm->EmitInt8(dwarf::DW_OP_plus_uconst); 2725 Asm->EmitULEB128(DV.getAddrElement(++i)); 2726 } else if (Element == DIBuilder::OpDeref) { 2727 if (!Loc.isReg()) 2728 Asm->EmitInt8(dwarf::DW_OP_deref); 2729 } else 2730 llvm_unreachable("unknown Opcode found in complex address"); 2731 } 2732 } 2733 } 2734 // else ... ignore constant fp. There is not any good way to 2735 // to represent them here in dwarf. 2736 Asm->OutStreamer.EmitLabel(end); 2737 } 2738 } 2739} 2740 2741struct SymbolCUSorter { 2742 SymbolCUSorter(const MCStreamer &s) : Streamer(s) {} 2743 const MCStreamer &Streamer; 2744 2745 bool operator() (const SymbolCU &A, const SymbolCU &B) { 2746 unsigned IA = A.Sym ? Streamer.GetSymbolOrder(A.Sym) : 0; 2747 unsigned IB = B.Sym ? Streamer.GetSymbolOrder(B.Sym) : 0; 2748 2749 // Symbols with no order assigned should be placed at the end. 2750 // (e.g. section end labels) 2751 if (IA == 0) 2752 IA = (unsigned)(-1); 2753 if (IB == 0) 2754 IB = (unsigned)(-1); 2755 return IA < IB; 2756 } 2757}; 2758 2759static bool CUSort(const CompileUnit *A, const CompileUnit *B) { 2760 return (A->getUniqueID() < B->getUniqueID()); 2761} 2762 2763struct ArangeSpan { 2764 const MCSymbol *Start, *End; 2765}; 2766 2767// Emit a debug aranges section, containing a CU lookup for any 2768// address we can tie back to a CU. 2769void DwarfDebug::emitDebugARanges() { 2770 // Start the dwarf aranges section. 2771 Asm->OutStreamer 2772 .SwitchSection(Asm->getObjFileLowering().getDwarfARangesSection()); 2773 2774 typedef DenseMap<CompileUnit *, std::vector<ArangeSpan> > SpansType; 2775 2776 SpansType Spans; 2777 2778 // Build a list of sections used. 2779 std::vector<const MCSection *> Sections; 2780 for (SectionMapType::iterator it = SectionMap.begin(); it != SectionMap.end(); 2781 it++) { 2782 const MCSection *Section = it->first; 2783 Sections.push_back(Section); 2784 } 2785 2786 // Sort the sections into order. 2787 // This is only done to ensure consistent output order across different runs. 2788 std::sort(Sections.begin(), Sections.end(), SectionSort); 2789 2790 // Build a set of address spans, sorted by CU. 2791 for (size_t SecIdx=0;SecIdx<Sections.size();SecIdx++) { 2792 const MCSection *Section = Sections[SecIdx]; 2793 SmallVector<SymbolCU, 8> &List = SectionMap[Section]; 2794 if (List.size() < 2) 2795 continue; 2796 2797 // Sort the symbols by offset within the section. 2798 SymbolCUSorter sorter(Asm->OutStreamer); 2799 std::sort(List.begin(), List.end(), sorter); 2800 2801 // If we have no section (e.g. common), just write out 2802 // individual spans for each symbol. 2803 if (Section == NULL) { 2804 for (size_t n = 0; n < List.size(); n++) { 2805 const SymbolCU &Cur = List[n]; 2806 2807 ArangeSpan Span; 2808 Span.Start = Cur.Sym; 2809 Span.End = NULL; 2810 if (Cur.CU) 2811 Spans[Cur.CU].push_back(Span); 2812 } 2813 } else { 2814 // Build spans between each label. 2815 const MCSymbol *StartSym = List[0].Sym; 2816 for (size_t n = 1; n < List.size(); n++) { 2817 const SymbolCU &Prev = List[n - 1]; 2818 const SymbolCU &Cur = List[n]; 2819 2820 // Try and build the longest span we can within the same CU. 2821 if (Cur.CU != Prev.CU) { 2822 ArangeSpan Span; 2823 Span.Start = StartSym; 2824 Span.End = Cur.Sym; 2825 Spans[Prev.CU].push_back(Span); 2826 StartSym = Cur.Sym; 2827 } 2828 } 2829 } 2830 } 2831 2832 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2833 unsigned PtrSize = Asm->getDataLayout().getPointerSize(); 2834 2835 // Build a list of CUs used. 2836 std::vector<CompileUnit *> CUs; 2837 for (SpansType::iterator it = Spans.begin(); it != Spans.end(); it++) { 2838 CompileUnit *CU = it->first; 2839 CUs.push_back(CU); 2840 } 2841 2842 // Sort the CU list (again, to ensure consistent output order). 2843 std::sort(CUs.begin(), CUs.end(), CUSort); 2844 2845 // Emit an arange table for each CU we used. 2846 for (size_t CUIdx=0;CUIdx<CUs.size();CUIdx++) { 2847 CompileUnit *CU = CUs[CUIdx]; 2848 std::vector<ArangeSpan> &List = Spans[CU]; 2849 2850 // Emit size of content not including length itself. 2851 unsigned ContentSize 2852 = sizeof(int16_t) // DWARF ARange version number 2853 + sizeof(int32_t) // Offset of CU in the .debug_info section 2854 + sizeof(int8_t) // Pointer Size (in bytes) 2855 + sizeof(int8_t); // Segment Size (in bytes) 2856 2857 unsigned TupleSize = PtrSize * 2; 2858 2859 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple. 2860 unsigned Padding = 0; 2861 while (((sizeof(int32_t) + ContentSize + Padding) % TupleSize) != 0) 2862 Padding++; 2863 2864 ContentSize += Padding; 2865 ContentSize += (List.size() + 1) * TupleSize; 2866 2867 // For each compile unit, write the list of spans it covers. 2868 Asm->OutStreamer.AddComment("Length of ARange Set"); 2869 Asm->EmitInt32(ContentSize); 2870 Asm->OutStreamer.AddComment("DWARF Arange version number"); 2871 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION); 2872 Asm->OutStreamer.AddComment("Offset Into Debug Info Section"); 2873 Asm->EmitSectionOffset( 2874 Asm->GetTempSymbol(ISec->getLabelBeginName(), CU->getUniqueID()), 2875 DwarfInfoSectionSym); 2876 Asm->OutStreamer.AddComment("Address Size (in bytes)"); 2877 Asm->EmitInt8(PtrSize); 2878 Asm->OutStreamer.AddComment("Segment Size (in bytes)"); 2879 Asm->EmitInt8(0); 2880 2881 for (unsigned n = 0; n < Padding; n++) 2882 Asm->EmitInt8(0xff); 2883 2884 for (unsigned n = 0; n < List.size(); n++) { 2885 const ArangeSpan &Span = List[n]; 2886 Asm->EmitLabelReference(Span.Start, PtrSize); 2887 2888 // Calculate the size as being from the span start to it's end. 2889 if (Span.End) { 2890 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize); 2891 } else { 2892 // For symbols without an end marker (e.g. common), we 2893 // write a single arange entry containing just that one symbol. 2894 uint64_t Size = SymSize[Span.Start]; 2895 if (Size == 0) 2896 Size = 1; 2897 2898 Asm->OutStreamer.EmitIntValue(Size, PtrSize); 2899 } 2900 } 2901 2902 Asm->OutStreamer.AddComment("ARange terminator"); 2903 Asm->OutStreamer.EmitIntValue(0, PtrSize); 2904 Asm->OutStreamer.EmitIntValue(0, PtrSize); 2905 } 2906} 2907 2908// Emit visible names into a debug ranges section. 2909void DwarfDebug::emitDebugRanges() { 2910 // Start the dwarf ranges section. 2911 Asm->OutStreamer 2912 .SwitchSection(Asm->getObjFileLowering().getDwarfRangesSection()); 2913 unsigned char Size = Asm->getDataLayout().getPointerSize(); 2914 for (SmallVectorImpl<const MCSymbol *>::iterator 2915 I = DebugRangeSymbols.begin(), E = DebugRangeSymbols.end(); 2916 I != E; ++I) { 2917 if (*I) 2918 Asm->OutStreamer.EmitSymbolValue(const_cast<MCSymbol*>(*I), Size); 2919 else 2920 Asm->OutStreamer.EmitIntValue(0, Size); 2921 } 2922} 2923 2924// Emit visible names into a debug macinfo section. 2925void DwarfDebug::emitDebugMacInfo() { 2926 if (const MCSection *LineInfo = 2927 Asm->getObjFileLowering().getDwarfMacroInfoSection()) { 2928 // Start the dwarf macinfo section. 2929 Asm->OutStreamer.SwitchSection(LineInfo); 2930 } 2931} 2932 2933// DWARF5 Experimental Separate Dwarf emitters. 2934 2935// This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list, 2936// DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id, 2937// DW_AT_ranges_base, DW_AT_addr_base. 2938CompileUnit *DwarfDebug::constructSkeletonCU(const CompileUnit *CU) { 2939 2940 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit); 2941 CompileUnit *NewCU = new CompileUnit(CU->getUniqueID(), Die, CU->getNode(), 2942 Asm, this, &SkeletonHolder); 2943 2944 NewCU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name, 2945 DICompileUnit(CU->getNode()).getSplitDebugFilename()); 2946 2947 // Relocate to the beginning of the addr_base section, else 0 for the 2948 // beginning of the one for this compile unit. 2949 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2950 NewCU->addLabel(Die, dwarf::DW_AT_GNU_addr_base, dwarf::DW_FORM_sec_offset, 2951 DwarfAddrSectionSym); 2952 else 2953 NewCU->addUInt(Die, dwarf::DW_AT_GNU_addr_base, 2954 dwarf::DW_FORM_sec_offset, 0); 2955 2956 // 2.17.1 requires that we use DW_AT_low_pc for a single entry point 2957 // into an entity. We're using 0, or a NULL label for this. 2958 NewCU->addUInt(Die, dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr, 0); 2959 2960 // DW_AT_stmt_list is a offset of line number information for this 2961 // compile unit in debug_line section. 2962 // FIXME: Should handle multiple compile units. 2963 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2964 NewCU->addLabel(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 2965 DwarfLineSectionSym); 2966 else 2967 NewCU->addUInt(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 0); 2968 2969 if (!CompilationDir.empty()) 2970 NewCU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir); 2971 2972 // Flags to let the linker know we have emitted new style pubnames. 2973 if (GenerateGnuPubSections) { 2974 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2975 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_sec_offset, 2976 Asm->GetTempSymbol("gnu_pubnames", NewCU->getUniqueID())); 2977 else 2978 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_data4, 2979 Asm->GetTempSymbol("gnu_pubnames", NewCU->getUniqueID()), 2980 DwarfGnuPubNamesSectionSym); 2981 2982 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2983 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_sec_offset, 2984 Asm->GetTempSymbol("gnu_pubtypes", NewCU->getUniqueID())); 2985 else 2986 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_data4, 2987 Asm->GetTempSymbol("gnu_pubtypes", NewCU->getUniqueID()), 2988 DwarfGnuPubTypesSectionSym); 2989 } 2990 2991 // Flag if we've emitted any ranges and their location for the compile unit. 2992 if (DebugRangeSymbols.size()) { 2993 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2994 NewCU->addLabel(Die, dwarf::DW_AT_GNU_ranges_base, 2995 dwarf::DW_FORM_sec_offset, DwarfDebugRangeSectionSym); 2996 else 2997 NewCU->addUInt(Die, dwarf::DW_AT_GNU_ranges_base, dwarf::DW_FORM_data4, 2998 0); 2999 } 3000 3001 SkeletonHolder.addUnit(NewCU); 3002 SkeletonCUs.push_back(NewCU); 3003 3004 return NewCU; 3005} 3006 3007void DwarfDebug::emitSkeletonAbbrevs(const MCSection *Section) { 3008 assert(useSplitDwarf() && "No split dwarf debug info?"); 3009 emitAbbrevs(Section, &SkeletonAbbrevs); 3010} 3011 3012// Emit the .debug_info.dwo section for separated dwarf. This contains the 3013// compile units that would normally be in debug_info. 3014void DwarfDebug::emitDebugInfoDWO() { 3015 assert(useSplitDwarf() && "No split dwarf debug info?"); 3016 InfoHolder.emitUnits(this, Asm->getObjFileLowering().getDwarfInfoDWOSection(), 3017 Asm->getObjFileLowering().getDwarfAbbrevDWOSection(), 3018 DwarfAbbrevDWOSectionSym); 3019} 3020 3021// Emit the .debug_abbrev.dwo section for separated dwarf. This contains the 3022// abbreviations for the .debug_info.dwo section. 3023void DwarfDebug::emitDebugAbbrevDWO() { 3024 assert(useSplitDwarf() && "No split dwarf?"); 3025 emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection(), 3026 &Abbreviations); 3027} 3028 3029// Emit the .debug_str.dwo section for separated dwarf. This contains the 3030// string section and is identical in format to traditional .debug_str 3031// sections. 3032void DwarfDebug::emitDebugStrDWO() { 3033 assert(useSplitDwarf() && "No split dwarf?"); 3034 const MCSection *OffSec = Asm->getObjFileLowering() 3035 .getDwarfStrOffDWOSection(); 3036 const MCSymbol *StrSym = DwarfStrSectionSym; 3037 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(), 3038 OffSec, StrSym); 3039} 3040