DwarfDebug.cpp revision 9e39e0d56d105f97b9d8f851403619bb0d9f780d
1//===-- llvm/CodeGen/DwarfDebug.cpp - Dwarf Debug Framework ---------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file contains support for writing dwarf debug info into asm files. 11// 12//===----------------------------------------------------------------------===// 13 14#define DEBUG_TYPE "dwarfdebug" 15#include "DwarfDebug.h" 16#include "DIE.h" 17#include "DIEHash.h" 18#include "DwarfAccelTable.h" 19#include "DwarfCompileUnit.h" 20#include "llvm/ADT/STLExtras.h" 21#include "llvm/ADT/Statistic.h" 22#include "llvm/ADT/StringExtras.h" 23#include "llvm/ADT/Triple.h" 24#include "llvm/CodeGen/MachineFunction.h" 25#include "llvm/CodeGen/MachineModuleInfo.h" 26#include "llvm/DIBuilder.h" 27#include "llvm/DebugInfo.h" 28#include "llvm/IR/Constants.h" 29#include "llvm/IR/DataLayout.h" 30#include "llvm/IR/Instructions.h" 31#include "llvm/IR/Module.h" 32#include "llvm/MC/MCAsmInfo.h" 33#include "llvm/MC/MCSection.h" 34#include "llvm/MC/MCStreamer.h" 35#include "llvm/MC/MCSymbol.h" 36#include "llvm/Support/CommandLine.h" 37#include "llvm/Support/Debug.h" 38#include "llvm/Support/Dwarf.h" 39#include "llvm/Support/ErrorHandling.h" 40#include "llvm/Support/FormattedStream.h" 41#include "llvm/Support/MD5.h" 42#include "llvm/Support/Path.h" 43#include "llvm/Support/Timer.h" 44#include "llvm/Support/ValueHandle.h" 45#include "llvm/Target/TargetFrameLowering.h" 46#include "llvm/Target/TargetLoweringObjectFile.h" 47#include "llvm/Target/TargetMachine.h" 48#include "llvm/Target/TargetOptions.h" 49#include "llvm/Target/TargetRegisterInfo.h" 50using namespace llvm; 51 52static cl::opt<bool> 53DisableDebugInfoPrinting("disable-debug-info-print", cl::Hidden, 54 cl::desc("Disable debug info printing")); 55 56static cl::opt<bool> UnknownLocations( 57 "use-unknown-locations", cl::Hidden, 58 cl::desc("Make an absence of debug location information explicit."), 59 cl::init(false)); 60 61static cl::opt<bool> 62GenerateODRHash("generate-odr-hash", cl::Hidden, 63 cl::desc("Add an ODR hash to external type DIEs."), 64 cl::init(false)); 65 66static cl::opt<bool> 67GenerateCUHash("generate-cu-hash", cl::Hidden, 68 cl::desc("Add the CU hash as the dwo_id."), 69 cl::init(false)); 70 71static cl::opt<bool> 72GenerateGnuPubSections("generate-gnu-dwarf-pub-sections", cl::Hidden, 73 cl::desc("Generate GNU-style pubnames and pubtypes"), 74 cl::init(false)); 75 76namespace { 77enum DefaultOnOff { 78 Default, 79 Enable, 80 Disable 81}; 82} 83 84static cl::opt<DefaultOnOff> 85DwarfAccelTables("dwarf-accel-tables", cl::Hidden, 86 cl::desc("Output prototype dwarf accelerator tables."), 87 cl::values(clEnumVal(Default, "Default for platform"), 88 clEnumVal(Enable, "Enabled"), 89 clEnumVal(Disable, "Disabled"), clEnumValEnd), 90 cl::init(Default)); 91 92static cl::opt<DefaultOnOff> 93SplitDwarf("split-dwarf", cl::Hidden, 94 cl::desc("Output prototype dwarf split debug info."), 95 cl::values(clEnumVal(Default, "Default for platform"), 96 clEnumVal(Enable, "Enabled"), 97 clEnumVal(Disable, "Disabled"), clEnumValEnd), 98 cl::init(Default)); 99 100static cl::opt<DefaultOnOff> 101DwarfPubSections("generate-dwarf-pub-sections", cl::Hidden, 102 cl::desc("Generate DWARF pubnames and pubtypes sections"), 103 cl::values(clEnumVal(Default, "Default for platform"), 104 clEnumVal(Enable, "Enabled"), 105 clEnumVal(Disable, "Disabled"), clEnumValEnd), 106 cl::init(Default)); 107 108static const char *const DWARFGroupName = "DWARF Emission"; 109static const char *const DbgTimerName = "DWARF Debug Writer"; 110 111//===----------------------------------------------------------------------===// 112 113// Configuration values for initial hash set sizes (log2). 114// 115static const unsigned InitAbbreviationsSetSize = 9; // log2(512) 116 117namespace llvm { 118 119/// resolve - Look in the DwarfDebug map for the MDNode that 120/// corresponds to the reference. 121template <typename T> 122T DbgVariable::resolve(DIRef<T> Ref) const { 123 return DD->resolve(Ref); 124} 125 126DIType DbgVariable::getType() const { 127 DIType Ty = Var.getType(); 128 // FIXME: isBlockByrefVariable should be reformulated in terms of complex 129 // addresses instead. 130 if (Var.isBlockByrefVariable()) { 131 /* Byref variables, in Blocks, are declared by the programmer as 132 "SomeType VarName;", but the compiler creates a 133 __Block_byref_x_VarName struct, and gives the variable VarName 134 either the struct, or a pointer to the struct, as its type. This 135 is necessary for various behind-the-scenes things the compiler 136 needs to do with by-reference variables in blocks. 137 138 However, as far as the original *programmer* is concerned, the 139 variable should still have type 'SomeType', as originally declared. 140 141 The following function dives into the __Block_byref_x_VarName 142 struct to find the original type of the variable. This will be 143 passed back to the code generating the type for the Debug 144 Information Entry for the variable 'VarName'. 'VarName' will then 145 have the original type 'SomeType' in its debug information. 146 147 The original type 'SomeType' will be the type of the field named 148 'VarName' inside the __Block_byref_x_VarName struct. 149 150 NOTE: In order for this to not completely fail on the debugger 151 side, the Debug Information Entry for the variable VarName needs to 152 have a DW_AT_location that tells the debugger how to unwind through 153 the pointers and __Block_byref_x_VarName struct to find the actual 154 value of the variable. The function addBlockByrefType does this. */ 155 DIType subType = Ty; 156 uint16_t tag = Ty.getTag(); 157 158 if (tag == dwarf::DW_TAG_pointer_type) 159 subType = resolve(DIDerivedType(Ty).getTypeDerivedFrom()); 160 161 DIArray Elements = DICompositeType(subType).getTypeArray(); 162 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) { 163 DIDerivedType DT = DIDerivedType(Elements.getElement(i)); 164 if (getName() == DT.getName()) 165 return (resolve(DT.getTypeDerivedFrom())); 166 } 167 } 168 return Ty; 169} 170 171} // end llvm namespace 172 173/// Return Dwarf Version by checking module flags. 174static unsigned getDwarfVersionFromModule(const Module *M) { 175 Value *Val = M->getModuleFlag("Dwarf Version"); 176 if (!Val) 177 return dwarf::DWARF_VERSION; 178 return cast<ConstantInt>(Val)->getZExtValue(); 179} 180 181DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M) 182 : Asm(A), MMI(Asm->MMI), FirstCU(0), 183 AbbreviationsSet(InitAbbreviationsSetSize), 184 SourceIdMap(DIEValueAllocator), 185 PrevLabel(NULL), GlobalCUIndexCount(0), 186 InfoHolder(A, &AbbreviationsSet, &Abbreviations, "info_string", 187 DIEValueAllocator), 188 SkeletonAbbrevSet(InitAbbreviationsSetSize), 189 SkeletonHolder(A, &SkeletonAbbrevSet, &SkeletonAbbrevs, "skel_string", 190 DIEValueAllocator) { 191 192 DwarfInfoSectionSym = DwarfAbbrevSectionSym = 0; 193 DwarfStrSectionSym = TextSectionSym = 0; 194 DwarfDebugRangeSectionSym = DwarfDebugLocSectionSym = DwarfLineSectionSym = 0; 195 DwarfAddrSectionSym = 0; 196 DwarfAbbrevDWOSectionSym = DwarfStrDWOSectionSym = 0; 197 FunctionBeginSym = FunctionEndSym = 0; 198 199 // Turn on accelerator tables for Darwin by default, pubnames by 200 // default for non-Darwin, and handle split dwarf. 201 bool IsDarwin = Triple(A->getTargetTriple()).isOSDarwin(); 202 203 if (DwarfAccelTables == Default) 204 HasDwarfAccelTables = IsDarwin; 205 else 206 HasDwarfAccelTables = DwarfAccelTables == Enable; 207 208 if (SplitDwarf == Default) 209 HasSplitDwarf = false; 210 else 211 HasSplitDwarf = SplitDwarf == Enable; 212 213 if (DwarfPubSections == Default) 214 HasDwarfPubSections = !IsDarwin; 215 else 216 HasDwarfPubSections = DwarfPubSections == Enable; 217 218 DwarfVersion = getDwarfVersionFromModule(MMI->getModule()); 219 220 { 221 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 222 beginModule(); 223 } 224} 225 226// Switch to the specified MCSection and emit an assembler 227// temporary label to it if SymbolStem is specified. 228static MCSymbol *emitSectionSym(AsmPrinter *Asm, const MCSection *Section, 229 const char *SymbolStem = 0) { 230 Asm->OutStreamer.SwitchSection(Section); 231 if (!SymbolStem) return 0; 232 233 MCSymbol *TmpSym = Asm->GetTempSymbol(SymbolStem); 234 Asm->OutStreamer.EmitLabel(TmpSym); 235 return TmpSym; 236} 237 238MCSymbol *DwarfUnits::getStringPoolSym() { 239 return Asm->GetTempSymbol(StringPref); 240} 241 242MCSymbol *DwarfUnits::getStringPoolEntry(StringRef Str) { 243 std::pair<MCSymbol*, unsigned> &Entry = 244 StringPool.GetOrCreateValue(Str).getValue(); 245 if (Entry.first) return Entry.first; 246 247 Entry.second = NextStringPoolNumber++; 248 return Entry.first = Asm->GetTempSymbol(StringPref, Entry.second); 249} 250 251unsigned DwarfUnits::getStringPoolIndex(StringRef Str) { 252 std::pair<MCSymbol*, unsigned> &Entry = 253 StringPool.GetOrCreateValue(Str).getValue(); 254 if (Entry.first) return Entry.second; 255 256 Entry.second = NextStringPoolNumber++; 257 Entry.first = Asm->GetTempSymbol(StringPref, Entry.second); 258 return Entry.second; 259} 260 261unsigned DwarfUnits::getAddrPoolIndex(const MCSymbol *Sym) { 262 return getAddrPoolIndex(MCSymbolRefExpr::Create(Sym, Asm->OutContext)); 263} 264 265unsigned DwarfUnits::getAddrPoolIndex(const MCExpr *Sym) { 266 std::pair<DenseMap<const MCExpr *, unsigned>::iterator, bool> P = 267 AddressPool.insert(std::make_pair(Sym, NextAddrPoolNumber)); 268 if (P.second) 269 ++NextAddrPoolNumber; 270 return P.first->second; 271} 272 273// Define a unique number for the abbreviation. 274// 275void DwarfUnits::assignAbbrevNumber(DIEAbbrev &Abbrev) { 276 // Check the set for priors. 277 DIEAbbrev *InSet = AbbreviationsSet->GetOrInsertNode(&Abbrev); 278 279 // If it's newly added. 280 if (InSet == &Abbrev) { 281 // Add to abbreviation list. 282 Abbreviations->push_back(&Abbrev); 283 284 // Assign the vector position + 1 as its number. 285 Abbrev.setNumber(Abbreviations->size()); 286 } else { 287 // Assign existing abbreviation number. 288 Abbrev.setNumber(InSet->getNumber()); 289 } 290} 291 292static bool isObjCClass(StringRef Name) { 293 return Name.startswith("+") || Name.startswith("-"); 294} 295 296static bool hasObjCCategory(StringRef Name) { 297 if (!isObjCClass(Name)) return false; 298 299 return Name.find(") ") != StringRef::npos; 300} 301 302static void getObjCClassCategory(StringRef In, StringRef &Class, 303 StringRef &Category) { 304 if (!hasObjCCategory(In)) { 305 Class = In.slice(In.find('[') + 1, In.find(' ')); 306 Category = ""; 307 return; 308 } 309 310 Class = In.slice(In.find('[') + 1, In.find('(')); 311 Category = In.slice(In.find('[') + 1, In.find(' ')); 312 return; 313} 314 315static StringRef getObjCMethodName(StringRef In) { 316 return In.slice(In.find(' ') + 1, In.find(']')); 317} 318 319// Helper for sorting sections into a stable output order. 320static bool SectionSort(const MCSection *A, const MCSection *B) { 321 std::string LA = (A ? A->getLabelBeginName() : ""); 322 std::string LB = (B ? B->getLabelBeginName() : ""); 323 return LA < LB; 324} 325 326// Add the various names to the Dwarf accelerator table names. 327// TODO: Determine whether or not we should add names for programs 328// that do not have a DW_AT_name or DW_AT_linkage_name field - this 329// is only slightly different than the lookup of non-standard ObjC names. 330static void addSubprogramNames(CompileUnit *TheCU, DISubprogram SP, 331 DIE* Die) { 332 if (!SP.isDefinition()) return; 333 TheCU->addAccelName(SP.getName(), Die); 334 335 // If the linkage name is different than the name, go ahead and output 336 // that as well into the name table. 337 if (SP.getLinkageName() != "" && SP.getName() != SP.getLinkageName()) 338 TheCU->addAccelName(SP.getLinkageName(), Die); 339 340 // If this is an Objective-C selector name add it to the ObjC accelerator 341 // too. 342 if (isObjCClass(SP.getName())) { 343 StringRef Class, Category; 344 getObjCClassCategory(SP.getName(), Class, Category); 345 TheCU->addAccelObjC(Class, Die); 346 if (Category != "") 347 TheCU->addAccelObjC(Category, Die); 348 // Also add the base method name to the name table. 349 TheCU->addAccelName(getObjCMethodName(SP.getName()), Die); 350 } 351} 352 353/// isSubprogramContext - Return true if Context is either a subprogram 354/// or another context nested inside a subprogram. 355bool DwarfDebug::isSubprogramContext(const MDNode *Context) { 356 if (!Context) 357 return false; 358 DIDescriptor D(Context); 359 if (D.isSubprogram()) 360 return true; 361 if (D.isType()) 362 return isSubprogramContext(resolve(DIType(Context).getContext())); 363 return false; 364} 365 366// Find DIE for the given subprogram and attach appropriate DW_AT_low_pc 367// and DW_AT_high_pc attributes. If there are global variables in this 368// scope then create and insert DIEs for these variables. 369DIE *DwarfDebug::updateSubprogramScopeDIE(CompileUnit *SPCU, 370 const MDNode *SPNode) { 371 DIE *SPDie = SPCU->getDIE(SPNode); 372 373 assert(SPDie && "Unable to find subprogram DIE!"); 374 DISubprogram SP(SPNode); 375 376 // If we're updating an abstract DIE, then we will be adding the children and 377 // object pointer later on. But what we don't want to do is process the 378 // concrete DIE twice. 379 if (DIE *AbsSPDIE = AbstractSPDies.lookup(SPNode)) { 380 // Pick up abstract subprogram DIE. 381 SPDie = new DIE(dwarf::DW_TAG_subprogram); 382 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_abstract_origin, AbsSPDIE); 383 SPCU->addDie(SPDie); 384 } else { 385 DISubprogram SPDecl = SP.getFunctionDeclaration(); 386 if (!SPDecl.isSubprogram()) { 387 // There is not any need to generate specification DIE for a function 388 // defined at compile unit level. If a function is defined inside another 389 // function then gdb prefers the definition at top level and but does not 390 // expect specification DIE in parent function. So avoid creating 391 // specification DIE for a function defined inside a function. 392 DIScope SPContext = resolve(SP.getContext()); 393 if (SP.isDefinition() && !SPContext.isCompileUnit() && 394 !SPContext.isFile() && 395 !isSubprogramContext(SPContext)) { 396 SPCU->addFlag(SPDie, dwarf::DW_AT_declaration); 397 398 // Add arguments. 399 DICompositeType SPTy = SP.getType(); 400 DIArray Args = SPTy.getTypeArray(); 401 uint16_t SPTag = SPTy.getTag(); 402 if (SPTag == dwarf::DW_TAG_subroutine_type) 403 for (unsigned i = 1, N = Args.getNumElements(); i < N; ++i) { 404 DIE *Arg = new DIE(dwarf::DW_TAG_formal_parameter); 405 DIType ATy = DIType(Args.getElement(i)); 406 SPCU->addType(Arg, ATy); 407 if (ATy.isArtificial()) 408 SPCU->addFlag(Arg, dwarf::DW_AT_artificial); 409 if (ATy.isObjectPointer()) 410 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_object_pointer, Arg); 411 SPDie->addChild(Arg); 412 } 413 DIE *SPDeclDie = SPDie; 414 SPDie = new DIE(dwarf::DW_TAG_subprogram); 415 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_specification, SPDeclDie); 416 SPCU->addDie(SPDie); 417 } 418 } 419 } 420 421 SPCU->addLabelAddress(SPDie, dwarf::DW_AT_low_pc, 422 Asm->GetTempSymbol("func_begin", 423 Asm->getFunctionNumber())); 424 SPCU->addLabelAddress(SPDie, dwarf::DW_AT_high_pc, 425 Asm->GetTempSymbol("func_end", 426 Asm->getFunctionNumber())); 427 const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo(); 428 MachineLocation Location(RI->getFrameRegister(*Asm->MF)); 429 SPCU->addAddress(SPDie, dwarf::DW_AT_frame_base, Location); 430 431 // Add name to the name table, we do this here because we're guaranteed 432 // to have concrete versions of our DW_TAG_subprogram nodes. 433 addSubprogramNames(SPCU, SP, SPDie); 434 435 return SPDie; 436} 437 438/// Check whether we should create a DIE for the given Scope, return true 439/// if we don't create a DIE (the corresponding DIE is null). 440bool DwarfDebug::isLexicalScopeDIENull(LexicalScope *Scope) { 441 if (Scope->isAbstractScope()) 442 return false; 443 444 // We don't create a DIE if there is no Range. 445 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 446 if (Ranges.empty()) 447 return true; 448 449 if (Ranges.size() > 1) 450 return false; 451 452 // We don't create a DIE if we have a single Range and the end label 453 // is null. 454 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 455 MCSymbol *End = getLabelAfterInsn(RI->second); 456 return !End; 457} 458 459// Construct new DW_TAG_lexical_block for this scope and attach 460// DW_AT_low_pc/DW_AT_high_pc labels. 461DIE *DwarfDebug::constructLexicalScopeDIE(CompileUnit *TheCU, 462 LexicalScope *Scope) { 463 if (isLexicalScopeDIENull(Scope)) 464 return 0; 465 466 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_lexical_block); 467 if (Scope->isAbstractScope()) 468 return ScopeDIE; 469 470 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 471 // If we have multiple ranges, emit them into the range section. 472 if (Ranges.size() > 1) { 473 // .debug_range section has not been laid out yet. Emit offset in 474 // .debug_range as a uint, size 4, for now. emitDIE will handle 475 // DW_AT_ranges appropriately. 476 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_ranges, dwarf::DW_FORM_data4, 477 DebugRangeSymbols.size() 478 * Asm->getDataLayout().getPointerSize()); 479 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 480 RE = Ranges.end(); RI != RE; ++RI) { 481 DebugRangeSymbols.push_back(getLabelBeforeInsn(RI->first)); 482 DebugRangeSymbols.push_back(getLabelAfterInsn(RI->second)); 483 } 484 485 // Terminate the range list. 486 DebugRangeSymbols.push_back(NULL); 487 DebugRangeSymbols.push_back(NULL); 488 return ScopeDIE; 489 } 490 491 // Construct the address range for this DIE. 492 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 493 MCSymbol *Start = getLabelBeforeInsn(RI->first); 494 MCSymbol *End = getLabelAfterInsn(RI->second); 495 assert(End && "End label should not be null!"); 496 497 assert(Start->isDefined() && "Invalid starting label for an inlined scope!"); 498 assert(End->isDefined() && "Invalid end label for an inlined scope!"); 499 500 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_low_pc, Start); 501 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_high_pc, End); 502 503 return ScopeDIE; 504} 505 506// This scope represents inlined body of a function. Construct DIE to 507// represent this concrete inlined copy of the function. 508DIE *DwarfDebug::constructInlinedScopeDIE(CompileUnit *TheCU, 509 LexicalScope *Scope) { 510 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 511 assert(Ranges.empty() == false && 512 "LexicalScope does not have instruction markers!"); 513 514 if (!Scope->getScopeNode()) 515 return NULL; 516 DIScope DS(Scope->getScopeNode()); 517 DISubprogram InlinedSP = getDISubprogram(DS); 518 DIE *OriginDIE = TheCU->getDIE(InlinedSP); 519 if (!OriginDIE) { 520 DEBUG(dbgs() << "Unable to find original DIE for an inlined subprogram."); 521 return NULL; 522 } 523 524 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_inlined_subroutine); 525 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_abstract_origin, OriginDIE); 526 527 if (Ranges.size() > 1) { 528 // .debug_range section has not been laid out yet. Emit offset in 529 // .debug_range as a uint, size 4, for now. emitDIE will handle 530 // DW_AT_ranges appropriately. 531 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_ranges, dwarf::DW_FORM_data4, 532 DebugRangeSymbols.size() 533 * Asm->getDataLayout().getPointerSize()); 534 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 535 RE = Ranges.end(); RI != RE; ++RI) { 536 DebugRangeSymbols.push_back(getLabelBeforeInsn(RI->first)); 537 DebugRangeSymbols.push_back(getLabelAfterInsn(RI->second)); 538 } 539 DebugRangeSymbols.push_back(NULL); 540 DebugRangeSymbols.push_back(NULL); 541 } else { 542 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 543 MCSymbol *StartLabel = getLabelBeforeInsn(RI->first); 544 MCSymbol *EndLabel = getLabelAfterInsn(RI->second); 545 546 if (StartLabel == 0 || EndLabel == 0) 547 llvm_unreachable("Unexpected Start and End labels for an inlined scope!"); 548 549 assert(StartLabel->isDefined() && 550 "Invalid starting label for an inlined scope!"); 551 assert(EndLabel->isDefined() && "Invalid end label for an inlined scope!"); 552 553 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_low_pc, StartLabel); 554 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_high_pc, EndLabel); 555 } 556 557 InlinedSubprogramDIEs.insert(OriginDIE); 558 559 // Add the call site information to the DIE. 560 DILocation DL(Scope->getInlinedAt()); 561 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_file, None, 562 getOrCreateSourceID(DL.getFilename(), DL.getDirectory(), 563 TheCU->getUniqueID())); 564 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_line, None, DL.getLineNumber()); 565 566 // Add name to the name table, we do this here because we're guaranteed 567 // to have concrete versions of our DW_TAG_inlined_subprogram nodes. 568 addSubprogramNames(TheCU, InlinedSP, ScopeDIE); 569 570 return ScopeDIE; 571} 572 573DIE *DwarfDebug::createScopeChildrenDIE(CompileUnit *TheCU, LexicalScope *Scope, 574 SmallVectorImpl<DIE*> &Children) { 575 DIE *ObjectPointer = NULL; 576 577 // Collect arguments for current function. 578 if (LScopes.isCurrentFunctionScope(Scope)) 579 for (unsigned i = 0, N = CurrentFnArguments.size(); i < N; ++i) 580 if (DbgVariable *ArgDV = CurrentFnArguments[i]) 581 if (DIE *Arg = 582 TheCU->constructVariableDIE(ArgDV, Scope->isAbstractScope())) { 583 Children.push_back(Arg); 584 if (ArgDV->isObjectPointer()) ObjectPointer = Arg; 585 } 586 587 // Collect lexical scope children first. 588 const SmallVectorImpl<DbgVariable *> &Variables =ScopeVariables.lookup(Scope); 589 for (unsigned i = 0, N = Variables.size(); i < N; ++i) 590 if (DIE *Variable = 591 TheCU->constructVariableDIE(Variables[i], Scope->isAbstractScope())) { 592 Children.push_back(Variable); 593 if (Variables[i]->isObjectPointer()) ObjectPointer = Variable; 594 } 595 const SmallVectorImpl<LexicalScope *> &Scopes = Scope->getChildren(); 596 for (unsigned j = 0, M = Scopes.size(); j < M; ++j) 597 if (DIE *Nested = constructScopeDIE(TheCU, Scopes[j])) 598 Children.push_back(Nested); 599 return ObjectPointer; 600} 601 602// Construct a DIE for this scope. 603DIE *DwarfDebug::constructScopeDIE(CompileUnit *TheCU, LexicalScope *Scope) { 604 if (!Scope || !Scope->getScopeNode()) 605 return NULL; 606 607 DIScope DS(Scope->getScopeNode()); 608 609 SmallVector<DIE *, 8> Children; 610 DIE *ObjectPointer = NULL; 611 bool ChildrenCreated = false; 612 613 // We try to create the scope DIE first, then the children DIEs. This will 614 // avoid creating un-used children then removing them later when we find out 615 // the scope DIE is null. 616 DIE *ScopeDIE = NULL; 617 if (Scope->getInlinedAt()) 618 ScopeDIE = constructInlinedScopeDIE(TheCU, Scope); 619 else if (DS.isSubprogram()) { 620 ProcessedSPNodes.insert(DS); 621 if (Scope->isAbstractScope()) { 622 ScopeDIE = TheCU->getDIE(DS); 623 // Note down abstract DIE. 624 if (ScopeDIE) 625 AbstractSPDies.insert(std::make_pair(DS, ScopeDIE)); 626 } 627 else 628 ScopeDIE = updateSubprogramScopeDIE(TheCU, DS); 629 } 630 else { 631 // Early exit when we know the scope DIE is going to be null. 632 if (isLexicalScopeDIENull(Scope)) 633 return NULL; 634 635 // We create children here when we know the scope DIE is not going to be 636 // null and the children will be added to the scope DIE. 637 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children); 638 ChildrenCreated = true; 639 640 // There is no need to emit empty lexical block DIE. 641 std::pair<ImportedEntityMap::const_iterator, 642 ImportedEntityMap::const_iterator> Range = std::equal_range( 643 ScopesWithImportedEntities.begin(), ScopesWithImportedEntities.end(), 644 std::pair<const MDNode *, const MDNode *>(DS, (const MDNode*)0), 645 less_first()); 646 if (Children.empty() && Range.first == Range.second) 647 return NULL; 648 ScopeDIE = constructLexicalScopeDIE(TheCU, Scope); 649 assert(ScopeDIE && "Scope DIE should not be null."); 650 for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second; 651 ++i) 652 constructImportedEntityDIE(TheCU, i->second, ScopeDIE); 653 } 654 655 if (!ScopeDIE) { 656 assert(Children.empty() && 657 "We create children only when the scope DIE is not null."); 658 return NULL; 659 } 660 if (!ChildrenCreated) 661 // We create children when the scope DIE is not null. 662 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children); 663 664 // Add children 665 for (SmallVectorImpl<DIE *>::iterator I = Children.begin(), 666 E = Children.end(); I != E; ++I) 667 ScopeDIE->addChild(*I); 668 669 if (DS.isSubprogram() && ObjectPointer != NULL) 670 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, ObjectPointer); 671 672 if (DS.isSubprogram()) 673 TheCU->addPubTypes(DISubprogram(DS)); 674 675 return ScopeDIE; 676} 677 678// Look up the source id with the given directory and source file names. 679// If none currently exists, create a new id and insert it in the 680// SourceIds map. This can update DirectoryNames and SourceFileNames maps 681// as well. 682unsigned DwarfDebug::getOrCreateSourceID(StringRef FileName, 683 StringRef DirName, unsigned CUID) { 684 // If we use .loc in assembly, we can't separate .file entries according to 685 // compile units. Thus all files will belong to the default compile unit. 686 687 // FIXME: add a better feature test than hasRawTextSupport. Even better, 688 // extend .file to support this. 689 if (Asm->TM.hasMCUseLoc() && Asm->OutStreamer.hasRawTextSupport()) 690 CUID = 0; 691 692 // If FE did not provide a file name, then assume stdin. 693 if (FileName.empty()) 694 return getOrCreateSourceID("<stdin>", StringRef(), CUID); 695 696 // TODO: this might not belong here. See if we can factor this better. 697 if (DirName == CompilationDir) 698 DirName = ""; 699 700 // FileIDCUMap stores the current ID for the given compile unit. 701 unsigned SrcId = FileIDCUMap[CUID] + 1; 702 703 // We look up the CUID/file/dir by concatenating them with a zero byte. 704 SmallString<128> NamePair; 705 NamePair += utostr(CUID); 706 NamePair += '\0'; 707 NamePair += DirName; 708 NamePair += '\0'; // Zero bytes are not allowed in paths. 709 NamePair += FileName; 710 711 StringMapEntry<unsigned> &Ent = SourceIdMap.GetOrCreateValue(NamePair, SrcId); 712 if (Ent.getValue() != SrcId) 713 return Ent.getValue(); 714 715 FileIDCUMap[CUID] = SrcId; 716 // Print out a .file directive to specify files for .loc directives. 717 Asm->OutStreamer.EmitDwarfFileDirective(SrcId, DirName, FileName, CUID); 718 719 return SrcId; 720} 721 722// Create new CompileUnit for the given metadata node with tag 723// DW_TAG_compile_unit. 724CompileUnit *DwarfDebug::constructCompileUnit(const MDNode *N) { 725 DICompileUnit DIUnit(N); 726 StringRef FN = DIUnit.getFilename(); 727 CompilationDir = DIUnit.getDirectory(); 728 729 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit); 730 CompileUnit *NewCU = 731 new CompileUnit(GlobalCUIndexCount++, Die, N, Asm, this, &InfoHolder); 732 733 FileIDCUMap[NewCU->getUniqueID()] = 0; 734 // Call this to emit a .file directive if it wasn't emitted for the source 735 // file this CU comes from yet. 736 getOrCreateSourceID(FN, CompilationDir, NewCU->getUniqueID()); 737 738 NewCU->addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer()); 739 NewCU->addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2, 740 DIUnit.getLanguage()); 741 NewCU->addString(Die, dwarf::DW_AT_name, FN); 742 743 // 2.17.1 requires that we use DW_AT_low_pc for a single entry point 744 // into an entity. We're using 0 (or a NULL label) for this. For 745 // split dwarf it's in the skeleton CU so omit it here. 746 if (!useSplitDwarf()) 747 NewCU->addLabelAddress(Die, dwarf::DW_AT_low_pc, NULL); 748 749 // Define start line table label for each Compile Unit. 750 MCSymbol *LineTableStartSym = Asm->GetTempSymbol("line_table_start", 751 NewCU->getUniqueID()); 752 Asm->OutStreamer.getContext().setMCLineTableSymbol(LineTableStartSym, 753 NewCU->getUniqueID()); 754 755 // Use a single line table if we are using .loc and generating assembly. 756 bool UseTheFirstCU = 757 (Asm->TM.hasMCUseLoc() && Asm->OutStreamer.hasRawTextSupport()) || 758 (NewCU->getUniqueID() == 0); 759 760 if (!useSplitDwarf()) { 761 // DW_AT_stmt_list is a offset of line number information for this 762 // compile unit in debug_line section. For split dwarf this is 763 // left in the skeleton CU and so not included. 764 // The line table entries are not always emitted in assembly, so it 765 // is not okay to use line_table_start here. 766 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 767 NewCU->addLabel(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 768 UseTheFirstCU ? Asm->GetTempSymbol("section_line") 769 : LineTableStartSym); 770 else if (UseTheFirstCU) 771 NewCU->addUInt(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4, 0); 772 else 773 NewCU->addDelta(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4, 774 LineTableStartSym, DwarfLineSectionSym); 775 776 // If we're using split dwarf the compilation dir is going to be in the 777 // skeleton CU and so we don't need to duplicate it here. 778 if (!CompilationDir.empty()) 779 NewCU->addString(Die, dwarf::DW_AT_comp_dir, CompilationDir); 780 781 // Flags to let the linker know we have emitted new style pubnames. Only 782 // emit it here if we don't have a skeleton CU for split dwarf. 783 if (GenerateGnuPubSections) { 784 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 785 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubnames, 786 dwarf::DW_FORM_sec_offset, 787 Asm->GetTempSymbol("gnu_pubnames", 788 NewCU->getUniqueID())); 789 else 790 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_data4, 791 Asm->GetTempSymbol("gnu_pubnames", 792 NewCU->getUniqueID()), 793 DwarfGnuPubNamesSectionSym); 794 795 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 796 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubtypes, 797 dwarf::DW_FORM_sec_offset, 798 Asm->GetTempSymbol("gnu_pubtypes", 799 NewCU->getUniqueID())); 800 else 801 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_data4, 802 Asm->GetTempSymbol("gnu_pubtypes", 803 NewCU->getUniqueID()), 804 DwarfGnuPubTypesSectionSym); 805 } 806 } 807 808 if (DIUnit.isOptimized()) 809 NewCU->addFlag(Die, dwarf::DW_AT_APPLE_optimized); 810 811 StringRef Flags = DIUnit.getFlags(); 812 if (!Flags.empty()) 813 NewCU->addString(Die, dwarf::DW_AT_APPLE_flags, Flags); 814 815 if (unsigned RVer = DIUnit.getRunTimeVersion()) 816 NewCU->addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers, 817 dwarf::DW_FORM_data1, RVer); 818 819 if (!FirstCU) 820 FirstCU = NewCU; 821 822 InfoHolder.addUnit(NewCU); 823 824 CUMap.insert(std::make_pair(N, NewCU)); 825 return NewCU; 826} 827 828// Construct subprogram DIE. 829void DwarfDebug::constructSubprogramDIE(CompileUnit *TheCU, const MDNode *N) { 830 // 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. 1920unsigned 1921DwarfUnits::computeSizeAndOffset(DIE *Die, unsigned Offset) { 1922 // Get the children. 1923 const std::vector<DIE *> &Children = Die->getChildren(); 1924 1925 // Record the abbreviation. 1926 assignAbbrevNumber(Die->getAbbrev()); 1927 1928 // Get the abbreviation for this DIE. 1929 unsigned AbbrevNumber = Die->getAbbrevNumber(); 1930 const DIEAbbrev *Abbrev = Abbreviations->at(AbbrevNumber - 1); 1931 1932 // Set DIE offset 1933 Die->setOffset(Offset); 1934 1935 // Start the size with the size of abbreviation code. 1936 Offset += MCAsmInfo::getULEB128Size(AbbrevNumber); 1937 1938 const SmallVectorImpl<DIEValue*> &Values = Die->getValues(); 1939 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev->getData(); 1940 1941 // Size the DIE attribute values. 1942 for (unsigned i = 0, N = Values.size(); i < N; ++i) 1943 // Size attribute value. 1944 Offset += Values[i]->SizeOf(Asm, AbbrevData[i].getForm()); 1945 1946 // Size the DIE children if any. 1947 if (!Children.empty()) { 1948 assert(Abbrev->getChildrenFlag() == dwarf::DW_CHILDREN_yes && 1949 "Children flag not set"); 1950 1951 for (unsigned j = 0, M = Children.size(); j < M; ++j) 1952 Offset = computeSizeAndOffset(Children[j], Offset); 1953 1954 // End of children marker. 1955 Offset += sizeof(int8_t); 1956 } 1957 1958 Die->setSize(Offset - Die->getOffset()); 1959 return Offset; 1960} 1961 1962// Compute the size and offset for each DIE. 1963void DwarfUnits::computeSizeAndOffsets() { 1964 // Iterate over each compile unit and set the size and offsets for each 1965 // DIE within each compile unit. All offsets are CU relative. 1966 for (SmallVectorImpl<CompileUnit *>::iterator I = CUs.begin(), 1967 E = CUs.end(); I != E; ++I) { 1968 unsigned Offset = 1969 sizeof(int32_t) + // Length of Compilation Unit Info 1970 sizeof(int16_t) + // DWARF version number 1971 sizeof(int32_t) + // Offset Into Abbrev. Section 1972 sizeof(int8_t); // Pointer Size (in bytes) 1973 computeSizeAndOffset((*I)->getCUDie(), Offset); 1974 } 1975} 1976 1977// Emit initial Dwarf sections with a label at the start of each one. 1978void DwarfDebug::emitSectionLabels() { 1979 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); 1980 1981 // Dwarf sections base addresses. 1982 DwarfInfoSectionSym = 1983 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info"); 1984 DwarfAbbrevSectionSym = 1985 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev"); 1986 if (useSplitDwarf()) 1987 DwarfAbbrevDWOSectionSym = 1988 emitSectionSym(Asm, TLOF.getDwarfAbbrevDWOSection(), 1989 "section_abbrev_dwo"); 1990 emitSectionSym(Asm, TLOF.getDwarfARangesSection()); 1991 1992 if (const MCSection *MacroInfo = TLOF.getDwarfMacroInfoSection()) 1993 emitSectionSym(Asm, MacroInfo); 1994 1995 DwarfLineSectionSym = 1996 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line"); 1997 emitSectionSym(Asm, TLOF.getDwarfLocSection()); 1998 if (GenerateGnuPubSections) { 1999 DwarfGnuPubNamesSectionSym = 2000 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection()); 2001 DwarfGnuPubTypesSectionSym = 2002 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection()); 2003 } else if (HasDwarfPubSections) { 2004 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection()); 2005 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection()); 2006 } 2007 2008 DwarfStrSectionSym = 2009 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string"); 2010 if (useSplitDwarf()) { 2011 DwarfStrDWOSectionSym = 2012 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string"); 2013 DwarfAddrSectionSym = 2014 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec"); 2015 } 2016 DwarfDebugRangeSectionSym = emitSectionSym(Asm, TLOF.getDwarfRangesSection(), 2017 "debug_range"); 2018 2019 DwarfDebugLocSectionSym = emitSectionSym(Asm, TLOF.getDwarfLocSection(), 2020 "section_debug_loc"); 2021 2022 TextSectionSym = emitSectionSym(Asm, TLOF.getTextSection(), "text_begin"); 2023 emitSectionSym(Asm, TLOF.getDataSection()); 2024} 2025 2026// Recursively emits a debug information entry. 2027void DwarfDebug::emitDIE(DIE *Die, std::vector<DIEAbbrev *> *Abbrevs) { 2028 // Get the abbreviation for this DIE. 2029 unsigned AbbrevNumber = Die->getAbbrevNumber(); 2030 const DIEAbbrev *Abbrev = Abbrevs->at(AbbrevNumber - 1); 2031 2032 // Emit the code (index) for the abbreviation. 2033 if (Asm->isVerbose()) 2034 Asm->OutStreamer.AddComment("Abbrev [" + Twine(AbbrevNumber) + "] 0x" + 2035 Twine::utohexstr(Die->getOffset()) + ":0x" + 2036 Twine::utohexstr(Die->getSize()) + " " + 2037 dwarf::TagString(Abbrev->getTag())); 2038 Asm->EmitULEB128(AbbrevNumber); 2039 2040 const SmallVectorImpl<DIEValue*> &Values = Die->getValues(); 2041 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev->getData(); 2042 2043 // Emit the DIE attribute values. 2044 for (unsigned i = 0, N = Values.size(); i < N; ++i) { 2045 dwarf::Attribute Attr = AbbrevData[i].getAttribute(); 2046 dwarf::Form Form = AbbrevData[i].getForm(); 2047 assert(Form && "Too many attributes for DIE (check abbreviation)"); 2048 2049 if (Asm->isVerbose()) 2050 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr)); 2051 2052 switch (Attr) { 2053 case dwarf::DW_AT_ranges: { 2054 // DW_AT_range Value encodes offset in debug_range section. 2055 DIEInteger *V = cast<DIEInteger>(Values[i]); 2056 2057 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) { 2058 Asm->EmitLabelPlusOffset(DwarfDebugRangeSectionSym, 2059 V->getValue(), 2060 4); 2061 } else { 2062 Asm->EmitLabelOffsetDifference(DwarfDebugRangeSectionSym, 2063 V->getValue(), 2064 DwarfDebugRangeSectionSym, 2065 4); 2066 } 2067 break; 2068 } 2069 case dwarf::DW_AT_location: { 2070 if (DIELabel *L = dyn_cast<DIELabel>(Values[i])) { 2071 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2072 Asm->EmitLabelReference(L->getValue(), 4); 2073 else 2074 Asm->EmitLabelDifference(L->getValue(), DwarfDebugLocSectionSym, 4); 2075 } else { 2076 Values[i]->EmitValue(Asm, Form); 2077 } 2078 break; 2079 } 2080 case dwarf::DW_AT_accessibility: { 2081 if (Asm->isVerbose()) { 2082 DIEInteger *V = cast<DIEInteger>(Values[i]); 2083 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(V->getValue())); 2084 } 2085 Values[i]->EmitValue(Asm, Form); 2086 break; 2087 } 2088 default: 2089 // Emit an attribute using the defined form. 2090 Values[i]->EmitValue(Asm, Form); 2091 break; 2092 } 2093 } 2094 2095 // Emit the DIE children if any. 2096 if (Abbrev->getChildrenFlag() == dwarf::DW_CHILDREN_yes) { 2097 const std::vector<DIE *> &Children = Die->getChildren(); 2098 2099 for (unsigned j = 0, M = Children.size(); j < M; ++j) 2100 emitDIE(Children[j], Abbrevs); 2101 2102 if (Asm->isVerbose()) 2103 Asm->OutStreamer.AddComment("End Of Children Mark"); 2104 Asm->EmitInt8(0); 2105 } 2106} 2107 2108// Emit the various dwarf units to the unit section USection with 2109// the abbreviations going into ASection. 2110void DwarfUnits::emitUnits(DwarfDebug *DD, 2111 const MCSection *USection, 2112 const MCSection *ASection, 2113 const MCSymbol *ASectionSym) { 2114 Asm->OutStreamer.SwitchSection(USection); 2115 for (SmallVectorImpl<CompileUnit *>::iterator I = CUs.begin(), 2116 E = CUs.end(); I != E; ++I) { 2117 CompileUnit *TheCU = *I; 2118 DIE *Die = TheCU->getCUDie(); 2119 2120 // Emit the compile units header. 2121 Asm->OutStreamer 2122 .EmitLabel(Asm->GetTempSymbol(USection->getLabelBeginName(), 2123 TheCU->getUniqueID())); 2124 2125 // Emit size of content not including length itself 2126 unsigned ContentSize = Die->getSize() + 2127 sizeof(int16_t) + // DWARF version number 2128 sizeof(int32_t) + // Offset Into Abbrev. Section 2129 sizeof(int8_t); // Pointer Size (in bytes) 2130 2131 Asm->OutStreamer.AddComment("Length of Compilation Unit Info"); 2132 Asm->EmitInt32(ContentSize); 2133 Asm->OutStreamer.AddComment("DWARF version number"); 2134 Asm->EmitInt16(DD->getDwarfVersion()); 2135 Asm->OutStreamer.AddComment("Offset Into Abbrev. Section"); 2136 Asm->EmitSectionOffset(Asm->GetTempSymbol(ASection->getLabelBeginName()), 2137 ASectionSym); 2138 Asm->OutStreamer.AddComment("Address Size (in bytes)"); 2139 Asm->EmitInt8(Asm->getDataLayout().getPointerSize()); 2140 2141 DD->emitDIE(Die, Abbreviations); 2142 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol(USection->getLabelEndName(), 2143 TheCU->getUniqueID())); 2144 } 2145} 2146 2147// Emit the debug info section. 2148void DwarfDebug::emitDebugInfo() { 2149 DwarfUnits &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; 2150 2151 Holder.emitUnits(this, Asm->getObjFileLowering().getDwarfInfoSection(), 2152 Asm->getObjFileLowering().getDwarfAbbrevSection(), 2153 DwarfAbbrevSectionSym); 2154} 2155 2156// Emit the abbreviation section. 2157void DwarfDebug::emitAbbreviations() { 2158 if (!useSplitDwarf()) 2159 emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection(), 2160 &Abbreviations); 2161 else 2162 emitSkeletonAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection()); 2163} 2164 2165void DwarfDebug::emitAbbrevs(const MCSection *Section, 2166 std::vector<DIEAbbrev *> *Abbrevs) { 2167 // Check to see if it is worth the effort. 2168 if (!Abbrevs->empty()) { 2169 // Start the debug abbrev section. 2170 Asm->OutStreamer.SwitchSection(Section); 2171 2172 MCSymbol *Begin = Asm->GetTempSymbol(Section->getLabelBeginName()); 2173 Asm->OutStreamer.EmitLabel(Begin); 2174 2175 // For each abbrevation. 2176 for (unsigned i = 0, N = Abbrevs->size(); i < N; ++i) { 2177 // Get abbreviation data 2178 const DIEAbbrev *Abbrev = Abbrevs->at(i); 2179 2180 // Emit the abbrevations code (base 1 index.) 2181 Asm->EmitULEB128(Abbrev->getNumber(), "Abbreviation Code"); 2182 2183 // Emit the abbreviations data. 2184 Abbrev->Emit(Asm); 2185 } 2186 2187 // Mark end of abbreviations. 2188 Asm->EmitULEB128(0, "EOM(3)"); 2189 2190 MCSymbol *End = Asm->GetTempSymbol(Section->getLabelEndName()); 2191 Asm->OutStreamer.EmitLabel(End); 2192 } 2193} 2194 2195// Emit the last address of the section and the end of the line matrix. 2196void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) { 2197 // Define last address of section. 2198 Asm->OutStreamer.AddComment("Extended Op"); 2199 Asm->EmitInt8(0); 2200 2201 Asm->OutStreamer.AddComment("Op size"); 2202 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1); 2203 Asm->OutStreamer.AddComment("DW_LNE_set_address"); 2204 Asm->EmitInt8(dwarf::DW_LNE_set_address); 2205 2206 Asm->OutStreamer.AddComment("Section end label"); 2207 2208 Asm->OutStreamer.EmitSymbolValue(Asm->GetTempSymbol("section_end",SectionEnd), 2209 Asm->getDataLayout().getPointerSize()); 2210 2211 // Mark end of matrix. 2212 Asm->OutStreamer.AddComment("DW_LNE_end_sequence"); 2213 Asm->EmitInt8(0); 2214 Asm->EmitInt8(1); 2215 Asm->EmitInt8(1); 2216} 2217 2218// Emit visible names into a hashed accelerator table section. 2219void DwarfDebug::emitAccelNames() { 2220 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2221 dwarf::DW_FORM_data4)); 2222 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2223 E = CUMap.end(); I != E; ++I) { 2224 CompileUnit *TheCU = I->second; 2225 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelNames(); 2226 for (StringMap<std::vector<DIE*> >::const_iterator 2227 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2228 StringRef Name = GI->getKey(); 2229 const std::vector<DIE *> &Entities = GI->second; 2230 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2231 DE = Entities.end(); DI != DE; ++DI) 2232 AT.AddName(Name, (*DI)); 2233 } 2234 } 2235 2236 AT.FinalizeTable(Asm, "Names"); 2237 Asm->OutStreamer.SwitchSection( 2238 Asm->getObjFileLowering().getDwarfAccelNamesSection()); 2239 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin"); 2240 Asm->OutStreamer.EmitLabel(SectionBegin); 2241 2242 // Emit the full data. 2243 AT.Emit(Asm, SectionBegin, &InfoHolder); 2244} 2245 2246// Emit objective C classes and categories into a hashed accelerator table 2247// section. 2248void DwarfDebug::emitAccelObjC() { 2249 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2250 dwarf::DW_FORM_data4)); 2251 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2252 E = CUMap.end(); I != E; ++I) { 2253 CompileUnit *TheCU = I->second; 2254 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelObjC(); 2255 for (StringMap<std::vector<DIE*> >::const_iterator 2256 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2257 StringRef Name = GI->getKey(); 2258 const std::vector<DIE *> &Entities = GI->second; 2259 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2260 DE = Entities.end(); DI != DE; ++DI) 2261 AT.AddName(Name, (*DI)); 2262 } 2263 } 2264 2265 AT.FinalizeTable(Asm, "ObjC"); 2266 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2267 .getDwarfAccelObjCSection()); 2268 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin"); 2269 Asm->OutStreamer.EmitLabel(SectionBegin); 2270 2271 // Emit the full data. 2272 AT.Emit(Asm, SectionBegin, &InfoHolder); 2273} 2274 2275// Emit namespace dies into a hashed accelerator table. 2276void DwarfDebug::emitAccelNamespaces() { 2277 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2278 dwarf::DW_FORM_data4)); 2279 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2280 E = CUMap.end(); I != E; ++I) { 2281 CompileUnit *TheCU = I->second; 2282 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelNamespace(); 2283 for (StringMap<std::vector<DIE*> >::const_iterator 2284 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2285 StringRef Name = GI->getKey(); 2286 const std::vector<DIE *> &Entities = GI->second; 2287 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2288 DE = Entities.end(); DI != DE; ++DI) 2289 AT.AddName(Name, (*DI)); 2290 } 2291 } 2292 2293 AT.FinalizeTable(Asm, "namespac"); 2294 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2295 .getDwarfAccelNamespaceSection()); 2296 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin"); 2297 Asm->OutStreamer.EmitLabel(SectionBegin); 2298 2299 // Emit the full data. 2300 AT.Emit(Asm, SectionBegin, &InfoHolder); 2301} 2302 2303// Emit type dies into a hashed accelerator table. 2304void DwarfDebug::emitAccelTypes() { 2305 std::vector<DwarfAccelTable::Atom> Atoms; 2306 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2307 dwarf::DW_FORM_data4)); 2308 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, 2309 dwarf::DW_FORM_data2)); 2310 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, 2311 dwarf::DW_FORM_data1)); 2312 DwarfAccelTable AT(Atoms); 2313 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2314 E = CUMap.end(); I != E; ++I) { 2315 CompileUnit *TheCU = I->second; 2316 const StringMap<std::vector<std::pair<DIE*, unsigned > > > &Names 2317 = TheCU->getAccelTypes(); 2318 for (StringMap<std::vector<std::pair<DIE*, unsigned> > >::const_iterator 2319 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2320 StringRef Name = GI->getKey(); 2321 const std::vector<std::pair<DIE *, unsigned> > &Entities = GI->second; 2322 for (std::vector<std::pair<DIE *, unsigned> >::const_iterator DI 2323 = Entities.begin(), DE = Entities.end(); DI !=DE; ++DI) 2324 AT.AddName(Name, (*DI).first, (*DI).second); 2325 } 2326 } 2327 2328 AT.FinalizeTable(Asm, "types"); 2329 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2330 .getDwarfAccelTypesSection()); 2331 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin"); 2332 Asm->OutStreamer.EmitLabel(SectionBegin); 2333 2334 // Emit the full data. 2335 AT.Emit(Asm, SectionBegin, &InfoHolder); 2336} 2337 2338// Public name handling. 2339// The format for the various pubnames: 2340// 2341// dwarf pubnames - offset/name pairs where the offset is the offset into the CU 2342// for the DIE that is named. 2343// 2344// gnu pubnames - offset/index value/name tuples where the offset is the offset 2345// into the CU and the index value is computed according to the type of value 2346// for the DIE that is named. 2347// 2348// For type units the offset is the offset of the skeleton DIE. For split dwarf 2349// it's the offset within the debug_info/debug_types dwo section, however, the 2350// reference in the pubname header doesn't change. 2351 2352/// computeIndexValue - Compute the gdb index value for the DIE and CU. 2353static dwarf::PubIndexEntryDescriptor computeIndexValue(CompileUnit *CU, 2354 DIE *Die) { 2355 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC; 2356 2357 // We could have a specification DIE that has our most of our knowledge, 2358 // look for that now. 2359 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification); 2360 if (SpecVal) { 2361 DIE *SpecDIE = cast<DIEEntry>(SpecVal)->getEntry(); 2362 if (SpecDIE->findAttribute(dwarf::DW_AT_external)) 2363 Linkage = dwarf::GIEL_EXTERNAL; 2364 } else if (Die->findAttribute(dwarf::DW_AT_external)) 2365 Linkage = dwarf::GIEL_EXTERNAL; 2366 2367 switch (Die->getTag()) { 2368 case dwarf::DW_TAG_class_type: 2369 case dwarf::DW_TAG_structure_type: 2370 case dwarf::DW_TAG_union_type: 2371 case dwarf::DW_TAG_enumeration_type: 2372 return dwarf::PubIndexEntryDescriptor( 2373 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus 2374 ? dwarf::GIEL_STATIC 2375 : dwarf::GIEL_EXTERNAL); 2376 case dwarf::DW_TAG_typedef: 2377 case dwarf::DW_TAG_base_type: 2378 case dwarf::DW_TAG_subrange_type: 2379 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC); 2380 case dwarf::DW_TAG_namespace: 2381 return dwarf::GIEK_TYPE; 2382 case dwarf::DW_TAG_subprogram: 2383 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage); 2384 case dwarf::DW_TAG_constant: 2385 case dwarf::DW_TAG_variable: 2386 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage); 2387 case dwarf::DW_TAG_enumerator: 2388 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, 2389 dwarf::GIEL_STATIC); 2390 default: 2391 return dwarf::GIEK_NONE; 2392 } 2393} 2394 2395/// emitDebugPubNames - Emit visible names into a debug pubnames section. 2396/// 2397void DwarfDebug::emitDebugPubNames(bool GnuStyle) { 2398 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2399 const MCSection *PSec = 2400 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection() 2401 : Asm->getObjFileLowering().getDwarfPubNamesSection(); 2402 2403 typedef DenseMap<const MDNode*, CompileUnit*> CUMapType; 2404 for (CUMapType::iterator I = CUMap.begin(), E = CUMap.end(); I != E; ++I) { 2405 CompileUnit *TheCU = I->second; 2406 unsigned ID = TheCU->getUniqueID(); 2407 2408 // Start the dwarf pubnames section. 2409 Asm->OutStreamer.SwitchSection(PSec); 2410 2411 // Emit a label so we can reference the beginning of this pubname section. 2412 if (GnuStyle) 2413 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("gnu_pubnames", 2414 TheCU->getUniqueID())); 2415 2416 // Emit the header. 2417 Asm->OutStreamer.AddComment("Length of Public Names Info"); 2418 Asm->EmitLabelDifference(Asm->GetTempSymbol("pubnames_end", ID), 2419 Asm->GetTempSymbol("pubnames_begin", ID), 4); 2420 2421 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("pubnames_begin", ID)); 2422 2423 Asm->OutStreamer.AddComment("DWARF Version"); 2424 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION); 2425 2426 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info"); 2427 Asm->EmitSectionOffset(Asm->GetTempSymbol(ISec->getLabelBeginName(), ID), 2428 DwarfInfoSectionSym); 2429 2430 Asm->OutStreamer.AddComment("Compilation Unit Length"); 2431 Asm->EmitLabelDifference(Asm->GetTempSymbol(ISec->getLabelEndName(), ID), 2432 Asm->GetTempSymbol(ISec->getLabelBeginName(), ID), 2433 4); 2434 2435 // Emit the pubnames for this compilation unit. 2436 const StringMap<DIE*> &Globals = TheCU->getGlobalNames(); 2437 for (StringMap<DIE*>::const_iterator 2438 GI = Globals.begin(), GE = Globals.end(); GI != GE; ++GI) { 2439 const char *Name = GI->getKeyData(); 2440 DIE *Entity = GI->second; 2441 2442 Asm->OutStreamer.AddComment("DIE offset"); 2443 Asm->EmitInt32(Entity->getOffset()); 2444 2445 if (GnuStyle) { 2446 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheCU, Entity); 2447 Asm->OutStreamer.AddComment( 2448 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " + 2449 dwarf::GDBIndexEntryLinkageString(Desc.Linkage)); 2450 Asm->EmitInt8(Desc.toBits()); 2451 } 2452 2453 if (Asm->isVerbose()) 2454 Asm->OutStreamer.AddComment("External Name"); 2455 Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength()+1)); 2456 } 2457 2458 Asm->OutStreamer.AddComment("End Mark"); 2459 Asm->EmitInt32(0); 2460 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("pubnames_end", ID)); 2461 } 2462} 2463 2464void DwarfDebug::emitDebugPubTypes(bool GnuStyle) { 2465 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2466 const MCSection *PSec = 2467 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection() 2468 : Asm->getObjFileLowering().getDwarfPubTypesSection(); 2469 2470 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2471 E = CUMap.end(); 2472 I != E; ++I) { 2473 CompileUnit *TheCU = I->second; 2474 // Start the dwarf pubtypes section. 2475 Asm->OutStreamer.SwitchSection(PSec); 2476 2477 // Emit a label so we can reference the beginning of this pubtype section. 2478 if (GnuStyle) 2479 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("gnu_pubtypes", 2480 TheCU->getUniqueID())); 2481 2482 // Emit the header. 2483 Asm->OutStreamer.AddComment("Length of Public Types Info"); 2484 Asm->EmitLabelDifference( 2485 Asm->GetTempSymbol("pubtypes_end", TheCU->getUniqueID()), 2486 Asm->GetTempSymbol("pubtypes_begin", TheCU->getUniqueID()), 4); 2487 2488 Asm->OutStreamer.EmitLabel( 2489 Asm->GetTempSymbol("pubtypes_begin", TheCU->getUniqueID())); 2490 2491 if (Asm->isVerbose()) 2492 Asm->OutStreamer.AddComment("DWARF Version"); 2493 Asm->EmitInt16(dwarf::DW_PUBTYPES_VERSION); 2494 2495 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info"); 2496 Asm->EmitSectionOffset( 2497 Asm->GetTempSymbol(ISec->getLabelBeginName(), TheCU->getUniqueID()), 2498 DwarfInfoSectionSym); 2499 2500 Asm->OutStreamer.AddComment("Compilation Unit Length"); 2501 Asm->EmitLabelDifference( 2502 Asm->GetTempSymbol(ISec->getLabelEndName(), TheCU->getUniqueID()), 2503 Asm->GetTempSymbol(ISec->getLabelBeginName(), TheCU->getUniqueID()), 4); 2504 2505 // Emit the pubtypes. 2506 const StringMap<DIE *> &Globals = TheCU->getGlobalTypes(); 2507 for (StringMap<DIE *>::const_iterator GI = Globals.begin(), 2508 GE = Globals.end(); 2509 GI != GE; ++GI) { 2510 const char *Name = GI->getKeyData(); 2511 DIE *Entity = GI->second; 2512 2513 if (Asm->isVerbose()) 2514 Asm->OutStreamer.AddComment("DIE offset"); 2515 Asm->EmitInt32(Entity->getOffset()); 2516 2517 if (GnuStyle) { 2518 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheCU, Entity); 2519 Asm->OutStreamer.AddComment( 2520 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " + 2521 dwarf::GDBIndexEntryLinkageString(Desc.Linkage)); 2522 Asm->EmitInt8(Desc.toBits()); 2523 } 2524 2525 if (Asm->isVerbose()) 2526 Asm->OutStreamer.AddComment("External Name"); 2527 2528 // Emit the name with a terminating null byte. 2529 Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength() + 1)); 2530 } 2531 2532 Asm->OutStreamer.AddComment("End Mark"); 2533 Asm->EmitInt32(0); 2534 Asm->OutStreamer.EmitLabel( 2535 Asm->GetTempSymbol("pubtypes_end", TheCU->getUniqueID())); 2536 } 2537} 2538 2539// Emit strings into a string section. 2540void DwarfUnits::emitStrings(const MCSection *StrSection, 2541 const MCSection *OffsetSection = NULL, 2542 const MCSymbol *StrSecSym = NULL) { 2543 2544 if (StringPool.empty()) return; 2545 2546 // Start the dwarf str section. 2547 Asm->OutStreamer.SwitchSection(StrSection); 2548 2549 // Get all of the string pool entries and put them in an array by their ID so 2550 // we can sort them. 2551 SmallVector<std::pair<unsigned, 2552 StringMapEntry<std::pair<MCSymbol*, unsigned> >*>, 64> Entries; 2553 2554 for (StringMap<std::pair<MCSymbol*, unsigned> >::iterator 2555 I = StringPool.begin(), E = StringPool.end(); 2556 I != E; ++I) 2557 Entries.push_back(std::make_pair(I->second.second, &*I)); 2558 2559 array_pod_sort(Entries.begin(), Entries.end()); 2560 2561 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2562 // Emit a label for reference from debug information entries. 2563 Asm->OutStreamer.EmitLabel(Entries[i].second->getValue().first); 2564 2565 // Emit the string itself with a terminating null byte. 2566 Asm->OutStreamer.EmitBytes(StringRef(Entries[i].second->getKeyData(), 2567 Entries[i].second->getKeyLength()+1)); 2568 } 2569 2570 // If we've got an offset section go ahead and emit that now as well. 2571 if (OffsetSection) { 2572 Asm->OutStreamer.SwitchSection(OffsetSection); 2573 unsigned offset = 0; 2574 unsigned size = 4; // FIXME: DWARF64 is 8. 2575 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2576 Asm->OutStreamer.EmitIntValue(offset, size); 2577 offset += Entries[i].second->getKeyLength() + 1; 2578 } 2579 } 2580} 2581 2582// Emit strings into a string section. 2583void DwarfUnits::emitAddresses(const MCSection *AddrSection) { 2584 2585 if (AddressPool.empty()) return; 2586 2587 // Start the dwarf addr section. 2588 Asm->OutStreamer.SwitchSection(AddrSection); 2589 2590 // Order the address pool entries by ID 2591 SmallVector<const MCExpr *, 64> Entries(AddressPool.size()); 2592 2593 for (DenseMap<const MCExpr *, unsigned>::iterator I = AddressPool.begin(), 2594 E = AddressPool.end(); 2595 I != E; ++I) 2596 Entries[I->second] = I->first; 2597 2598 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2599 // Emit an expression for reference from debug information entries. 2600 if (const MCExpr *Expr = Entries[i]) 2601 Asm->OutStreamer.EmitValue(Expr, Asm->getDataLayout().getPointerSize()); 2602 else 2603 Asm->OutStreamer.EmitIntValue(0, Asm->getDataLayout().getPointerSize()); 2604 } 2605 2606} 2607 2608// Emit visible names into a debug str section. 2609void DwarfDebug::emitDebugStr() { 2610 DwarfUnits &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; 2611 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection()); 2612} 2613 2614// Emit locations into the debug loc section. 2615void DwarfDebug::emitDebugLoc() { 2616 if (DotDebugLocEntries.empty()) 2617 return; 2618 2619 for (SmallVectorImpl<DotDebugLocEntry>::iterator 2620 I = DotDebugLocEntries.begin(), E = DotDebugLocEntries.end(); 2621 I != E; ++I) { 2622 DotDebugLocEntry &Entry = *I; 2623 if (I + 1 != DotDebugLocEntries.end()) 2624 Entry.Merge(I+1); 2625 } 2626 2627 // Start the dwarf loc section. 2628 Asm->OutStreamer.SwitchSection( 2629 Asm->getObjFileLowering().getDwarfLocSection()); 2630 unsigned char Size = Asm->getDataLayout().getPointerSize(); 2631 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", 0)); 2632 unsigned index = 1; 2633 for (SmallVectorImpl<DotDebugLocEntry>::iterator 2634 I = DotDebugLocEntries.begin(), E = DotDebugLocEntries.end(); 2635 I != E; ++I, ++index) { 2636 DotDebugLocEntry &Entry = *I; 2637 if (Entry.isMerged()) continue; 2638 if (Entry.isEmpty()) { 2639 Asm->OutStreamer.EmitIntValue(0, Size); 2640 Asm->OutStreamer.EmitIntValue(0, Size); 2641 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", index)); 2642 } else { 2643 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size); 2644 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size); 2645 DIVariable DV(Entry.getVariable()); 2646 Asm->OutStreamer.AddComment("Loc expr size"); 2647 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol(); 2648 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol(); 2649 Asm->EmitLabelDifference(end, begin, 2); 2650 Asm->OutStreamer.EmitLabel(begin); 2651 if (Entry.isInt()) { 2652 DIBasicType BTy(DV.getType()); 2653 if (BTy.Verify() && 2654 (BTy.getEncoding() == dwarf::DW_ATE_signed 2655 || BTy.getEncoding() == dwarf::DW_ATE_signed_char)) { 2656 Asm->OutStreamer.AddComment("DW_OP_consts"); 2657 Asm->EmitInt8(dwarf::DW_OP_consts); 2658 Asm->EmitSLEB128(Entry.getInt()); 2659 } else { 2660 Asm->OutStreamer.AddComment("DW_OP_constu"); 2661 Asm->EmitInt8(dwarf::DW_OP_constu); 2662 Asm->EmitULEB128(Entry.getInt()); 2663 } 2664 } else if (Entry.isLocation()) { 2665 MachineLocation Loc = Entry.getLoc(); 2666 if (!DV.hasComplexAddress()) 2667 // Regular entry. 2668 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2669 else { 2670 // Complex address entry. 2671 unsigned N = DV.getNumAddrElements(); 2672 unsigned i = 0; 2673 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) { 2674 if (Loc.getOffset()) { 2675 i = 2; 2676 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2677 Asm->OutStreamer.AddComment("DW_OP_deref"); 2678 Asm->EmitInt8(dwarf::DW_OP_deref); 2679 Asm->OutStreamer.AddComment("DW_OP_plus_uconst"); 2680 Asm->EmitInt8(dwarf::DW_OP_plus_uconst); 2681 Asm->EmitSLEB128(DV.getAddrElement(1)); 2682 } else { 2683 // If first address element is OpPlus then emit 2684 // DW_OP_breg + Offset instead of DW_OP_reg + Offset. 2685 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1)); 2686 Asm->EmitDwarfRegOp(TLoc, DV.isIndirect()); 2687 i = 2; 2688 } 2689 } else { 2690 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2691 } 2692 2693 // Emit remaining complex address elements. 2694 for (; i < N; ++i) { 2695 uint64_t Element = DV.getAddrElement(i); 2696 if (Element == DIBuilder::OpPlus) { 2697 Asm->EmitInt8(dwarf::DW_OP_plus_uconst); 2698 Asm->EmitULEB128(DV.getAddrElement(++i)); 2699 } else if (Element == DIBuilder::OpDeref) { 2700 if (!Loc.isReg()) 2701 Asm->EmitInt8(dwarf::DW_OP_deref); 2702 } else 2703 llvm_unreachable("unknown Opcode found in complex address"); 2704 } 2705 } 2706 } 2707 // else ... ignore constant fp. There is not any good way to 2708 // to represent them here in dwarf. 2709 Asm->OutStreamer.EmitLabel(end); 2710 } 2711 } 2712} 2713 2714struct SymbolCUSorter { 2715 SymbolCUSorter(const MCStreamer &s) : Streamer(s) {} 2716 const MCStreamer &Streamer; 2717 2718 bool operator() (const SymbolCU &A, const SymbolCU &B) { 2719 unsigned IA = A.Sym ? Streamer.GetSymbolOrder(A.Sym) : 0; 2720 unsigned IB = B.Sym ? Streamer.GetSymbolOrder(B.Sym) : 0; 2721 2722 // Symbols with no order assigned should be placed at the end. 2723 // (e.g. section end labels) 2724 if (IA == 0) 2725 IA = (unsigned)(-1); 2726 if (IB == 0) 2727 IB = (unsigned)(-1); 2728 return IA < IB; 2729 } 2730}; 2731 2732static bool CUSort(const CompileUnit *A, const CompileUnit *B) { 2733 return (A->getUniqueID() < B->getUniqueID()); 2734} 2735 2736struct ArangeSpan { 2737 const MCSymbol *Start, *End; 2738}; 2739 2740// Emit a debug aranges section, containing a CU lookup for any 2741// address we can tie back to a CU. 2742void DwarfDebug::emitDebugARanges() { 2743 // Start the dwarf aranges section. 2744 Asm->OutStreamer 2745 .SwitchSection(Asm->getObjFileLowering().getDwarfARangesSection()); 2746 2747 typedef DenseMap<CompileUnit *, std::vector<ArangeSpan> > SpansType; 2748 2749 SpansType Spans; 2750 2751 // Build a list of sections used. 2752 std::vector<const MCSection *> Sections; 2753 for (SectionMapType::iterator it = SectionMap.begin(); it != SectionMap.end(); 2754 it++) { 2755 const MCSection *Section = it->first; 2756 Sections.push_back(Section); 2757 } 2758 2759 // Sort the sections into order. 2760 // This is only done to ensure consistent output order across different runs. 2761 std::sort(Sections.begin(), Sections.end(), SectionSort); 2762 2763 // Build a set of address spans, sorted by CU. 2764 for (size_t SecIdx=0;SecIdx<Sections.size();SecIdx++) { 2765 const MCSection *Section = Sections[SecIdx]; 2766 SmallVector<SymbolCU, 8> &List = SectionMap[Section]; 2767 if (List.size() < 2) 2768 continue; 2769 2770 // Sort the symbols by offset within the section. 2771 SymbolCUSorter sorter(Asm->OutStreamer); 2772 std::sort(List.begin(), List.end(), sorter); 2773 2774 // If we have no section (e.g. common), just write out 2775 // individual spans for each symbol. 2776 if (Section == NULL) { 2777 for (size_t n = 0; n < List.size(); n++) { 2778 const SymbolCU &Cur = List[n]; 2779 2780 ArangeSpan Span; 2781 Span.Start = Cur.Sym; 2782 Span.End = NULL; 2783 if (Cur.CU) 2784 Spans[Cur.CU].push_back(Span); 2785 } 2786 } else { 2787 // Build spans between each label. 2788 const MCSymbol *StartSym = List[0].Sym; 2789 for (size_t n = 1; n < List.size(); n++) { 2790 const SymbolCU &Prev = List[n - 1]; 2791 const SymbolCU &Cur = List[n]; 2792 2793 // Try and build the longest span we can within the same CU. 2794 if (Cur.CU != Prev.CU) { 2795 ArangeSpan Span; 2796 Span.Start = StartSym; 2797 Span.End = Cur.Sym; 2798 Spans[Prev.CU].push_back(Span); 2799 StartSym = Cur.Sym; 2800 } 2801 } 2802 } 2803 } 2804 2805 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2806 unsigned PtrSize = Asm->getDataLayout().getPointerSize(); 2807 2808 // Build a list of CUs used. 2809 std::vector<CompileUnit *> CUs; 2810 for (SpansType::iterator it = Spans.begin(); it != Spans.end(); it++) { 2811 CompileUnit *CU = it->first; 2812 CUs.push_back(CU); 2813 } 2814 2815 // Sort the CU list (again, to ensure consistent output order). 2816 std::sort(CUs.begin(), CUs.end(), CUSort); 2817 2818 // Emit an arange table for each CU we used. 2819 for (size_t CUIdx=0;CUIdx<CUs.size();CUIdx++) { 2820 CompileUnit *CU = CUs[CUIdx]; 2821 std::vector<ArangeSpan> &List = Spans[CU]; 2822 2823 // Emit size of content not including length itself. 2824 unsigned ContentSize 2825 = sizeof(int16_t) // DWARF ARange version number 2826 + sizeof(int32_t) // Offset of CU in the .debug_info section 2827 + sizeof(int8_t) // Pointer Size (in bytes) 2828 + sizeof(int8_t); // Segment Size (in bytes) 2829 2830 unsigned TupleSize = PtrSize * 2; 2831 2832 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple. 2833 unsigned Padding = 0; 2834 while (((sizeof(int32_t) + ContentSize + Padding) % TupleSize) != 0) 2835 Padding++; 2836 2837 ContentSize += Padding; 2838 ContentSize += (List.size() + 1) * TupleSize; 2839 2840 // For each compile unit, write the list of spans it covers. 2841 Asm->OutStreamer.AddComment("Length of ARange Set"); 2842 Asm->EmitInt32(ContentSize); 2843 Asm->OutStreamer.AddComment("DWARF Arange version number"); 2844 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION); 2845 Asm->OutStreamer.AddComment("Offset Into Debug Info Section"); 2846 Asm->EmitSectionOffset( 2847 Asm->GetTempSymbol(ISec->getLabelBeginName(), CU->getUniqueID()), 2848 DwarfInfoSectionSym); 2849 Asm->OutStreamer.AddComment("Address Size (in bytes)"); 2850 Asm->EmitInt8(PtrSize); 2851 Asm->OutStreamer.AddComment("Segment Size (in bytes)"); 2852 Asm->EmitInt8(0); 2853 2854 for (unsigned n = 0; n < Padding; n++) 2855 Asm->EmitInt8(0xff); 2856 2857 for (unsigned n = 0; n < List.size(); n++) { 2858 const ArangeSpan &Span = List[n]; 2859 Asm->EmitLabelReference(Span.Start, PtrSize); 2860 2861 // Calculate the size as being from the span start to it's end. 2862 if (Span.End) { 2863 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize); 2864 } else { 2865 // For symbols without an end marker (e.g. common), we 2866 // write a single arange entry containing just that one symbol. 2867 uint64_t Size = SymSize[Span.Start]; 2868 if (Size == 0) 2869 Size = 1; 2870 2871 Asm->OutStreamer.EmitIntValue(Size, PtrSize); 2872 } 2873 } 2874 2875 Asm->OutStreamer.AddComment("ARange terminator"); 2876 Asm->OutStreamer.EmitIntValue(0, PtrSize); 2877 Asm->OutStreamer.EmitIntValue(0, PtrSize); 2878 } 2879} 2880 2881// Emit visible names into a debug ranges section. 2882void DwarfDebug::emitDebugRanges() { 2883 // Start the dwarf ranges section. 2884 Asm->OutStreamer 2885 .SwitchSection(Asm->getObjFileLowering().getDwarfRangesSection()); 2886 unsigned char Size = Asm->getDataLayout().getPointerSize(); 2887 for (SmallVectorImpl<const MCSymbol *>::iterator 2888 I = DebugRangeSymbols.begin(), E = DebugRangeSymbols.end(); 2889 I != E; ++I) { 2890 if (*I) 2891 Asm->OutStreamer.EmitSymbolValue(const_cast<MCSymbol*>(*I), Size); 2892 else 2893 Asm->OutStreamer.EmitIntValue(0, Size); 2894 } 2895} 2896 2897// Emit visible names into a debug macinfo section. 2898void DwarfDebug::emitDebugMacInfo() { 2899 if (const MCSection *LineInfo = 2900 Asm->getObjFileLowering().getDwarfMacroInfoSection()) { 2901 // Start the dwarf macinfo section. 2902 Asm->OutStreamer.SwitchSection(LineInfo); 2903 } 2904} 2905 2906// DWARF5 Experimental Separate Dwarf emitters. 2907 2908// This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list, 2909// DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id, 2910// DW_AT_ranges_base, DW_AT_addr_base. 2911CompileUnit *DwarfDebug::constructSkeletonCU(const CompileUnit *CU) { 2912 2913 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit); 2914 CompileUnit *NewCU = new CompileUnit(CU->getUniqueID(), Die, CU->getNode(), 2915 Asm, this, &SkeletonHolder); 2916 2917 NewCU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name, 2918 DICompileUnit(CU->getNode()).getSplitDebugFilename()); 2919 2920 // Relocate to the beginning of the addr_base section, else 0 for the 2921 // beginning of the one for this compile unit. 2922 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2923 NewCU->addLabel(Die, dwarf::DW_AT_GNU_addr_base, dwarf::DW_FORM_sec_offset, 2924 DwarfAddrSectionSym); 2925 else 2926 NewCU->addUInt(Die, dwarf::DW_AT_GNU_addr_base, 2927 dwarf::DW_FORM_sec_offset, 0); 2928 2929 // 2.17.1 requires that we use DW_AT_low_pc for a single entry point 2930 // into an entity. We're using 0, or a NULL label for this. 2931 NewCU->addUInt(Die, dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr, 0); 2932 2933 // DW_AT_stmt_list is a offset of line number information for this 2934 // compile unit in debug_line section. 2935 // FIXME: Should handle multiple compile units. 2936 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2937 NewCU->addLabel(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 2938 DwarfLineSectionSym); 2939 else 2940 NewCU->addUInt(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 0); 2941 2942 if (!CompilationDir.empty()) 2943 NewCU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir); 2944 2945 // Flags to let the linker know we have emitted new style pubnames. 2946 if (GenerateGnuPubSections) { 2947 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2948 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_sec_offset, 2949 Asm->GetTempSymbol("gnu_pubnames", NewCU->getUniqueID())); 2950 else 2951 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_data4, 2952 Asm->GetTempSymbol("gnu_pubnames", NewCU->getUniqueID()), 2953 DwarfGnuPubNamesSectionSym); 2954 2955 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2956 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_sec_offset, 2957 Asm->GetTempSymbol("gnu_pubtypes", NewCU->getUniqueID())); 2958 else 2959 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_data4, 2960 Asm->GetTempSymbol("gnu_pubtypes", NewCU->getUniqueID()), 2961 DwarfGnuPubTypesSectionSym); 2962 } 2963 2964 // Flag if we've emitted any ranges and their location for the compile unit. 2965 if (DebugRangeSymbols.size()) { 2966 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2967 NewCU->addLabel(Die, dwarf::DW_AT_GNU_ranges_base, 2968 dwarf::DW_FORM_sec_offset, DwarfDebugRangeSectionSym); 2969 else 2970 NewCU->addUInt(Die, dwarf::DW_AT_GNU_ranges_base, dwarf::DW_FORM_data4, 2971 0); 2972 } 2973 2974 SkeletonHolder.addUnit(NewCU); 2975 SkeletonCUs.push_back(NewCU); 2976 2977 return NewCU; 2978} 2979 2980void DwarfDebug::emitSkeletonAbbrevs(const MCSection *Section) { 2981 assert(useSplitDwarf() && "No split dwarf debug info?"); 2982 emitAbbrevs(Section, &SkeletonAbbrevs); 2983} 2984 2985// Emit the .debug_info.dwo section for separated dwarf. This contains the 2986// compile units that would normally be in debug_info. 2987void DwarfDebug::emitDebugInfoDWO() { 2988 assert(useSplitDwarf() && "No split dwarf debug info?"); 2989 InfoHolder.emitUnits(this, Asm->getObjFileLowering().getDwarfInfoDWOSection(), 2990 Asm->getObjFileLowering().getDwarfAbbrevDWOSection(), 2991 DwarfAbbrevDWOSectionSym); 2992} 2993 2994// Emit the .debug_abbrev.dwo section for separated dwarf. This contains the 2995// abbreviations for the .debug_info.dwo section. 2996void DwarfDebug::emitDebugAbbrevDWO() { 2997 assert(useSplitDwarf() && "No split dwarf?"); 2998 emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection(), 2999 &Abbreviations); 3000} 3001 3002// Emit the .debug_str.dwo section for separated dwarf. This contains the 3003// string section and is identical in format to traditional .debug_str 3004// sections. 3005void DwarfDebug::emitDebugStrDWO() { 3006 assert(useSplitDwarf() && "No split dwarf?"); 3007 const MCSection *OffSec = Asm->getObjFileLowering() 3008 .getDwarfStrOffDWOSection(); 3009 const MCSymbol *StrSym = DwarfStrSectionSym; 3010 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(), 3011 OffSec, StrSym); 3012} 3013