DwarfDebug.cpp revision 39cd7d48c07f6d8d104432a6b671c9cb3ede2b75
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_abstract_origin: { 2054 DIEEntry *E = cast<DIEEntry>(Values[i]); 2055 DIE *Origin = E->getEntry(); 2056 unsigned Addr = Origin->getOffset(); 2057 Asm->EmitInt32(Addr); 2058 break; 2059 } 2060 case dwarf::DW_AT_ranges: { 2061 // DW_AT_range Value encodes offset in debug_range section. 2062 DIEInteger *V = cast<DIEInteger>(Values[i]); 2063 2064 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) { 2065 Asm->EmitLabelPlusOffset(DwarfDebugRangeSectionSym, 2066 V->getValue(), 2067 4); 2068 } else { 2069 Asm->EmitLabelOffsetDifference(DwarfDebugRangeSectionSym, 2070 V->getValue(), 2071 DwarfDebugRangeSectionSym, 2072 4); 2073 } 2074 break; 2075 } 2076 case dwarf::DW_AT_location: { 2077 if (DIELabel *L = dyn_cast<DIELabel>(Values[i])) { 2078 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2079 Asm->EmitLabelReference(L->getValue(), 4); 2080 else 2081 Asm->EmitLabelDifference(L->getValue(), DwarfDebugLocSectionSym, 4); 2082 } else { 2083 Values[i]->EmitValue(Asm, Form); 2084 } 2085 break; 2086 } 2087 case dwarf::DW_AT_accessibility: { 2088 if (Asm->isVerbose()) { 2089 DIEInteger *V = cast<DIEInteger>(Values[i]); 2090 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(V->getValue())); 2091 } 2092 Values[i]->EmitValue(Asm, Form); 2093 break; 2094 } 2095 default: 2096 // Emit an attribute using the defined form. 2097 Values[i]->EmitValue(Asm, Form); 2098 break; 2099 } 2100 } 2101 2102 // Emit the DIE children if any. 2103 if (Abbrev->getChildrenFlag() == dwarf::DW_CHILDREN_yes) { 2104 const std::vector<DIE *> &Children = Die->getChildren(); 2105 2106 for (unsigned j = 0, M = Children.size(); j < M; ++j) 2107 emitDIE(Children[j], Abbrevs); 2108 2109 if (Asm->isVerbose()) 2110 Asm->OutStreamer.AddComment("End Of Children Mark"); 2111 Asm->EmitInt8(0); 2112 } 2113} 2114 2115// Emit the various dwarf units to the unit section USection with 2116// the abbreviations going into ASection. 2117void DwarfUnits::emitUnits(DwarfDebug *DD, 2118 const MCSection *USection, 2119 const MCSection *ASection, 2120 const MCSymbol *ASectionSym) { 2121 Asm->OutStreamer.SwitchSection(USection); 2122 for (SmallVectorImpl<CompileUnit *>::iterator I = CUs.begin(), 2123 E = CUs.end(); I != E; ++I) { 2124 CompileUnit *TheCU = *I; 2125 DIE *Die = TheCU->getCUDie(); 2126 2127 // Emit the compile units header. 2128 Asm->OutStreamer 2129 .EmitLabel(Asm->GetTempSymbol(USection->getLabelBeginName(), 2130 TheCU->getUniqueID())); 2131 2132 // Emit size of content not including length itself 2133 unsigned ContentSize = Die->getSize() + 2134 sizeof(int16_t) + // DWARF version number 2135 sizeof(int32_t) + // Offset Into Abbrev. Section 2136 sizeof(int8_t); // Pointer Size (in bytes) 2137 2138 Asm->OutStreamer.AddComment("Length of Compilation Unit Info"); 2139 Asm->EmitInt32(ContentSize); 2140 Asm->OutStreamer.AddComment("DWARF version number"); 2141 Asm->EmitInt16(DD->getDwarfVersion()); 2142 Asm->OutStreamer.AddComment("Offset Into Abbrev. Section"); 2143 Asm->EmitSectionOffset(Asm->GetTempSymbol(ASection->getLabelBeginName()), 2144 ASectionSym); 2145 Asm->OutStreamer.AddComment("Address Size (in bytes)"); 2146 Asm->EmitInt8(Asm->getDataLayout().getPointerSize()); 2147 2148 DD->emitDIE(Die, Abbreviations); 2149 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol(USection->getLabelEndName(), 2150 TheCU->getUniqueID())); 2151 } 2152} 2153 2154// Emit the debug info section. 2155void DwarfDebug::emitDebugInfo() { 2156 DwarfUnits &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; 2157 2158 Holder.emitUnits(this, Asm->getObjFileLowering().getDwarfInfoSection(), 2159 Asm->getObjFileLowering().getDwarfAbbrevSection(), 2160 DwarfAbbrevSectionSym); 2161} 2162 2163// Emit the abbreviation section. 2164void DwarfDebug::emitAbbreviations() { 2165 if (!useSplitDwarf()) 2166 emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection(), 2167 &Abbreviations); 2168 else 2169 emitSkeletonAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection()); 2170} 2171 2172void DwarfDebug::emitAbbrevs(const MCSection *Section, 2173 std::vector<DIEAbbrev *> *Abbrevs) { 2174 // Check to see if it is worth the effort. 2175 if (!Abbrevs->empty()) { 2176 // Start the debug abbrev section. 2177 Asm->OutStreamer.SwitchSection(Section); 2178 2179 MCSymbol *Begin = Asm->GetTempSymbol(Section->getLabelBeginName()); 2180 Asm->OutStreamer.EmitLabel(Begin); 2181 2182 // For each abbrevation. 2183 for (unsigned i = 0, N = Abbrevs->size(); i < N; ++i) { 2184 // Get abbreviation data 2185 const DIEAbbrev *Abbrev = Abbrevs->at(i); 2186 2187 // Emit the abbrevations code (base 1 index.) 2188 Asm->EmitULEB128(Abbrev->getNumber(), "Abbreviation Code"); 2189 2190 // Emit the abbreviations data. 2191 Abbrev->Emit(Asm); 2192 } 2193 2194 // Mark end of abbreviations. 2195 Asm->EmitULEB128(0, "EOM(3)"); 2196 2197 MCSymbol *End = Asm->GetTempSymbol(Section->getLabelEndName()); 2198 Asm->OutStreamer.EmitLabel(End); 2199 } 2200} 2201 2202// Emit the last address of the section and the end of the line matrix. 2203void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) { 2204 // Define last address of section. 2205 Asm->OutStreamer.AddComment("Extended Op"); 2206 Asm->EmitInt8(0); 2207 2208 Asm->OutStreamer.AddComment("Op size"); 2209 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1); 2210 Asm->OutStreamer.AddComment("DW_LNE_set_address"); 2211 Asm->EmitInt8(dwarf::DW_LNE_set_address); 2212 2213 Asm->OutStreamer.AddComment("Section end label"); 2214 2215 Asm->OutStreamer.EmitSymbolValue(Asm->GetTempSymbol("section_end",SectionEnd), 2216 Asm->getDataLayout().getPointerSize()); 2217 2218 // Mark end of matrix. 2219 Asm->OutStreamer.AddComment("DW_LNE_end_sequence"); 2220 Asm->EmitInt8(0); 2221 Asm->EmitInt8(1); 2222 Asm->EmitInt8(1); 2223} 2224 2225// Emit visible names into a hashed accelerator table section. 2226void DwarfDebug::emitAccelNames() { 2227 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2228 dwarf::DW_FORM_data4)); 2229 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2230 E = CUMap.end(); I != E; ++I) { 2231 CompileUnit *TheCU = I->second; 2232 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelNames(); 2233 for (StringMap<std::vector<DIE*> >::const_iterator 2234 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2235 StringRef Name = GI->getKey(); 2236 const std::vector<DIE *> &Entities = GI->second; 2237 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2238 DE = Entities.end(); DI != DE; ++DI) 2239 AT.AddName(Name, (*DI)); 2240 } 2241 } 2242 2243 AT.FinalizeTable(Asm, "Names"); 2244 Asm->OutStreamer.SwitchSection( 2245 Asm->getObjFileLowering().getDwarfAccelNamesSection()); 2246 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin"); 2247 Asm->OutStreamer.EmitLabel(SectionBegin); 2248 2249 // Emit the full data. 2250 AT.Emit(Asm, SectionBegin, &InfoHolder); 2251} 2252 2253// Emit objective C classes and categories into a hashed accelerator table 2254// section. 2255void DwarfDebug::emitAccelObjC() { 2256 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2257 dwarf::DW_FORM_data4)); 2258 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2259 E = CUMap.end(); I != E; ++I) { 2260 CompileUnit *TheCU = I->second; 2261 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelObjC(); 2262 for (StringMap<std::vector<DIE*> >::const_iterator 2263 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2264 StringRef Name = GI->getKey(); 2265 const std::vector<DIE *> &Entities = GI->second; 2266 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2267 DE = Entities.end(); DI != DE; ++DI) 2268 AT.AddName(Name, (*DI)); 2269 } 2270 } 2271 2272 AT.FinalizeTable(Asm, "ObjC"); 2273 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2274 .getDwarfAccelObjCSection()); 2275 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin"); 2276 Asm->OutStreamer.EmitLabel(SectionBegin); 2277 2278 // Emit the full data. 2279 AT.Emit(Asm, SectionBegin, &InfoHolder); 2280} 2281 2282// Emit namespace dies into a hashed accelerator table. 2283void DwarfDebug::emitAccelNamespaces() { 2284 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2285 dwarf::DW_FORM_data4)); 2286 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2287 E = CUMap.end(); I != E; ++I) { 2288 CompileUnit *TheCU = I->second; 2289 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelNamespace(); 2290 for (StringMap<std::vector<DIE*> >::const_iterator 2291 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2292 StringRef Name = GI->getKey(); 2293 const std::vector<DIE *> &Entities = GI->second; 2294 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2295 DE = Entities.end(); DI != DE; ++DI) 2296 AT.AddName(Name, (*DI)); 2297 } 2298 } 2299 2300 AT.FinalizeTable(Asm, "namespac"); 2301 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2302 .getDwarfAccelNamespaceSection()); 2303 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin"); 2304 Asm->OutStreamer.EmitLabel(SectionBegin); 2305 2306 // Emit the full data. 2307 AT.Emit(Asm, SectionBegin, &InfoHolder); 2308} 2309 2310// Emit type dies into a hashed accelerator table. 2311void DwarfDebug::emitAccelTypes() { 2312 std::vector<DwarfAccelTable::Atom> Atoms; 2313 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2314 dwarf::DW_FORM_data4)); 2315 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, 2316 dwarf::DW_FORM_data2)); 2317 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, 2318 dwarf::DW_FORM_data1)); 2319 DwarfAccelTable AT(Atoms); 2320 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2321 E = CUMap.end(); I != E; ++I) { 2322 CompileUnit *TheCU = I->second; 2323 const StringMap<std::vector<std::pair<DIE*, unsigned > > > &Names 2324 = TheCU->getAccelTypes(); 2325 for (StringMap<std::vector<std::pair<DIE*, unsigned> > >::const_iterator 2326 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2327 StringRef Name = GI->getKey(); 2328 const std::vector<std::pair<DIE *, unsigned> > &Entities = GI->second; 2329 for (std::vector<std::pair<DIE *, unsigned> >::const_iterator DI 2330 = Entities.begin(), DE = Entities.end(); DI !=DE; ++DI) 2331 AT.AddName(Name, (*DI).first, (*DI).second); 2332 } 2333 } 2334 2335 AT.FinalizeTable(Asm, "types"); 2336 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2337 .getDwarfAccelTypesSection()); 2338 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin"); 2339 Asm->OutStreamer.EmitLabel(SectionBegin); 2340 2341 // Emit the full data. 2342 AT.Emit(Asm, SectionBegin, &InfoHolder); 2343} 2344 2345// Public name handling. 2346// The format for the various pubnames: 2347// 2348// dwarf pubnames - offset/name pairs where the offset is the offset into the CU 2349// for the DIE that is named. 2350// 2351// gnu pubnames - offset/index value/name tuples where the offset is the offset 2352// into the CU and the index value is computed according to the type of value 2353// for the DIE that is named. 2354// 2355// For type units the offset is the offset of the skeleton DIE. For split dwarf 2356// it's the offset within the debug_info/debug_types dwo section, however, the 2357// reference in the pubname header doesn't change. 2358 2359/// computeIndexValue - Compute the gdb index value for the DIE and CU. 2360static dwarf::PubIndexEntryDescriptor computeIndexValue(CompileUnit *CU, 2361 DIE *Die) { 2362 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC; 2363 2364 // We could have a specification DIE that has our most of our knowledge, 2365 // look for that now. 2366 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification); 2367 if (SpecVal) { 2368 DIE *SpecDIE = cast<DIEEntry>(SpecVal)->getEntry(); 2369 if (SpecDIE->findAttribute(dwarf::DW_AT_external)) 2370 Linkage = dwarf::GIEL_EXTERNAL; 2371 } else if (Die->findAttribute(dwarf::DW_AT_external)) 2372 Linkage = dwarf::GIEL_EXTERNAL; 2373 2374 switch (Die->getTag()) { 2375 case dwarf::DW_TAG_class_type: 2376 case dwarf::DW_TAG_structure_type: 2377 case dwarf::DW_TAG_union_type: 2378 case dwarf::DW_TAG_enumeration_type: 2379 return dwarf::PubIndexEntryDescriptor( 2380 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus 2381 ? dwarf::GIEL_STATIC 2382 : dwarf::GIEL_EXTERNAL); 2383 case dwarf::DW_TAG_typedef: 2384 case dwarf::DW_TAG_base_type: 2385 case dwarf::DW_TAG_subrange_type: 2386 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC); 2387 case dwarf::DW_TAG_namespace: 2388 return dwarf::GIEK_TYPE; 2389 case dwarf::DW_TAG_subprogram: 2390 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage); 2391 case dwarf::DW_TAG_constant: 2392 case dwarf::DW_TAG_variable: 2393 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage); 2394 case dwarf::DW_TAG_enumerator: 2395 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, 2396 dwarf::GIEL_STATIC); 2397 default: 2398 return dwarf::GIEK_NONE; 2399 } 2400} 2401 2402/// emitDebugPubNames - Emit visible names into a debug pubnames section. 2403/// 2404void DwarfDebug::emitDebugPubNames(bool GnuStyle) { 2405 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2406 const MCSection *PSec = 2407 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection() 2408 : Asm->getObjFileLowering().getDwarfPubNamesSection(); 2409 2410 typedef DenseMap<const MDNode*, CompileUnit*> CUMapType; 2411 for (CUMapType::iterator I = CUMap.begin(), E = CUMap.end(); I != E; ++I) { 2412 CompileUnit *TheCU = I->second; 2413 unsigned ID = TheCU->getUniqueID(); 2414 2415 // Start the dwarf pubnames section. 2416 Asm->OutStreamer.SwitchSection(PSec); 2417 2418 // Emit a label so we can reference the beginning of this pubname section. 2419 if (GnuStyle) 2420 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("gnu_pubnames", 2421 TheCU->getUniqueID())); 2422 2423 // Emit the header. 2424 Asm->OutStreamer.AddComment("Length of Public Names Info"); 2425 Asm->EmitLabelDifference(Asm->GetTempSymbol("pubnames_end", ID), 2426 Asm->GetTempSymbol("pubnames_begin", ID), 4); 2427 2428 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("pubnames_begin", ID)); 2429 2430 Asm->OutStreamer.AddComment("DWARF Version"); 2431 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION); 2432 2433 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info"); 2434 Asm->EmitSectionOffset(Asm->GetTempSymbol(ISec->getLabelBeginName(), ID), 2435 DwarfInfoSectionSym); 2436 2437 Asm->OutStreamer.AddComment("Compilation Unit Length"); 2438 Asm->EmitLabelDifference(Asm->GetTempSymbol(ISec->getLabelEndName(), ID), 2439 Asm->GetTempSymbol(ISec->getLabelBeginName(), ID), 2440 4); 2441 2442 // Emit the pubnames for this compilation unit. 2443 const StringMap<DIE*> &Globals = TheCU->getGlobalNames(); 2444 for (StringMap<DIE*>::const_iterator 2445 GI = Globals.begin(), GE = Globals.end(); GI != GE; ++GI) { 2446 const char *Name = GI->getKeyData(); 2447 DIE *Entity = GI->second; 2448 2449 Asm->OutStreamer.AddComment("DIE offset"); 2450 Asm->EmitInt32(Entity->getOffset()); 2451 2452 if (GnuStyle) { 2453 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheCU, Entity); 2454 Asm->OutStreamer.AddComment( 2455 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " + 2456 dwarf::GDBIndexEntryLinkageString(Desc.Linkage)); 2457 Asm->EmitInt8(Desc.toBits()); 2458 } 2459 2460 if (Asm->isVerbose()) 2461 Asm->OutStreamer.AddComment("External Name"); 2462 Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength()+1)); 2463 } 2464 2465 Asm->OutStreamer.AddComment("End Mark"); 2466 Asm->EmitInt32(0); 2467 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("pubnames_end", ID)); 2468 } 2469} 2470 2471void DwarfDebug::emitDebugPubTypes(bool GnuStyle) { 2472 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2473 const MCSection *PSec = 2474 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection() 2475 : Asm->getObjFileLowering().getDwarfPubTypesSection(); 2476 2477 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2478 E = CUMap.end(); 2479 I != E; ++I) { 2480 CompileUnit *TheCU = I->second; 2481 // Start the dwarf pubtypes section. 2482 Asm->OutStreamer.SwitchSection(PSec); 2483 2484 // Emit a label so we can reference the beginning of this pubtype section. 2485 if (GnuStyle) 2486 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("gnu_pubtypes", 2487 TheCU->getUniqueID())); 2488 2489 // Emit the header. 2490 Asm->OutStreamer.AddComment("Length of Public Types Info"); 2491 Asm->EmitLabelDifference( 2492 Asm->GetTempSymbol("pubtypes_end", TheCU->getUniqueID()), 2493 Asm->GetTempSymbol("pubtypes_begin", TheCU->getUniqueID()), 4); 2494 2495 Asm->OutStreamer.EmitLabel( 2496 Asm->GetTempSymbol("pubtypes_begin", TheCU->getUniqueID())); 2497 2498 if (Asm->isVerbose()) 2499 Asm->OutStreamer.AddComment("DWARF Version"); 2500 Asm->EmitInt16(dwarf::DW_PUBTYPES_VERSION); 2501 2502 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info"); 2503 Asm->EmitSectionOffset( 2504 Asm->GetTempSymbol(ISec->getLabelBeginName(), TheCU->getUniqueID()), 2505 DwarfInfoSectionSym); 2506 2507 Asm->OutStreamer.AddComment("Compilation Unit Length"); 2508 Asm->EmitLabelDifference( 2509 Asm->GetTempSymbol(ISec->getLabelEndName(), TheCU->getUniqueID()), 2510 Asm->GetTempSymbol(ISec->getLabelBeginName(), TheCU->getUniqueID()), 4); 2511 2512 // Emit the pubtypes. 2513 const StringMap<DIE *> &Globals = TheCU->getGlobalTypes(); 2514 for (StringMap<DIE *>::const_iterator GI = Globals.begin(), 2515 GE = Globals.end(); 2516 GI != GE; ++GI) { 2517 const char *Name = GI->getKeyData(); 2518 DIE *Entity = GI->second; 2519 2520 if (Asm->isVerbose()) 2521 Asm->OutStreamer.AddComment("DIE offset"); 2522 Asm->EmitInt32(Entity->getOffset()); 2523 2524 if (GnuStyle) { 2525 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheCU, Entity); 2526 Asm->OutStreamer.AddComment( 2527 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " + 2528 dwarf::GDBIndexEntryLinkageString(Desc.Linkage)); 2529 Asm->EmitInt8(Desc.toBits()); 2530 } 2531 2532 if (Asm->isVerbose()) 2533 Asm->OutStreamer.AddComment("External Name"); 2534 2535 // Emit the name with a terminating null byte. 2536 Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength() + 1)); 2537 } 2538 2539 Asm->OutStreamer.AddComment("End Mark"); 2540 Asm->EmitInt32(0); 2541 Asm->OutStreamer.EmitLabel( 2542 Asm->GetTempSymbol("pubtypes_end", TheCU->getUniqueID())); 2543 } 2544} 2545 2546// Emit strings into a string section. 2547void DwarfUnits::emitStrings(const MCSection *StrSection, 2548 const MCSection *OffsetSection = NULL, 2549 const MCSymbol *StrSecSym = NULL) { 2550 2551 if (StringPool.empty()) return; 2552 2553 // Start the dwarf str section. 2554 Asm->OutStreamer.SwitchSection(StrSection); 2555 2556 // Get all of the string pool entries and put them in an array by their ID so 2557 // we can sort them. 2558 SmallVector<std::pair<unsigned, 2559 StringMapEntry<std::pair<MCSymbol*, unsigned> >*>, 64> Entries; 2560 2561 for (StringMap<std::pair<MCSymbol*, unsigned> >::iterator 2562 I = StringPool.begin(), E = StringPool.end(); 2563 I != E; ++I) 2564 Entries.push_back(std::make_pair(I->second.second, &*I)); 2565 2566 array_pod_sort(Entries.begin(), Entries.end()); 2567 2568 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2569 // Emit a label for reference from debug information entries. 2570 Asm->OutStreamer.EmitLabel(Entries[i].second->getValue().first); 2571 2572 // Emit the string itself with a terminating null byte. 2573 Asm->OutStreamer.EmitBytes(StringRef(Entries[i].second->getKeyData(), 2574 Entries[i].second->getKeyLength()+1)); 2575 } 2576 2577 // If we've got an offset section go ahead and emit that now as well. 2578 if (OffsetSection) { 2579 Asm->OutStreamer.SwitchSection(OffsetSection); 2580 unsigned offset = 0; 2581 unsigned size = 4; // FIXME: DWARF64 is 8. 2582 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2583 Asm->OutStreamer.EmitIntValue(offset, size); 2584 offset += Entries[i].second->getKeyLength() + 1; 2585 } 2586 } 2587} 2588 2589// Emit strings into a string section. 2590void DwarfUnits::emitAddresses(const MCSection *AddrSection) { 2591 2592 if (AddressPool.empty()) return; 2593 2594 // Start the dwarf addr section. 2595 Asm->OutStreamer.SwitchSection(AddrSection); 2596 2597 // Order the address pool entries by ID 2598 SmallVector<const MCExpr *, 64> Entries(AddressPool.size()); 2599 2600 for (DenseMap<const MCExpr *, unsigned>::iterator I = AddressPool.begin(), 2601 E = AddressPool.end(); 2602 I != E; ++I) 2603 Entries[I->second] = I->first; 2604 2605 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2606 // Emit an expression for reference from debug information entries. 2607 if (const MCExpr *Expr = Entries[i]) 2608 Asm->OutStreamer.EmitValue(Expr, Asm->getDataLayout().getPointerSize()); 2609 else 2610 Asm->OutStreamer.EmitIntValue(0, Asm->getDataLayout().getPointerSize()); 2611 } 2612 2613} 2614 2615// Emit visible names into a debug str section. 2616void DwarfDebug::emitDebugStr() { 2617 DwarfUnits &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; 2618 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection()); 2619} 2620 2621// Emit locations into the debug loc section. 2622void DwarfDebug::emitDebugLoc() { 2623 if (DotDebugLocEntries.empty()) 2624 return; 2625 2626 for (SmallVectorImpl<DotDebugLocEntry>::iterator 2627 I = DotDebugLocEntries.begin(), E = DotDebugLocEntries.end(); 2628 I != E; ++I) { 2629 DotDebugLocEntry &Entry = *I; 2630 if (I + 1 != DotDebugLocEntries.end()) 2631 Entry.Merge(I+1); 2632 } 2633 2634 // Start the dwarf loc section. 2635 Asm->OutStreamer.SwitchSection( 2636 Asm->getObjFileLowering().getDwarfLocSection()); 2637 unsigned char Size = Asm->getDataLayout().getPointerSize(); 2638 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", 0)); 2639 unsigned index = 1; 2640 for (SmallVectorImpl<DotDebugLocEntry>::iterator 2641 I = DotDebugLocEntries.begin(), E = DotDebugLocEntries.end(); 2642 I != E; ++I, ++index) { 2643 DotDebugLocEntry &Entry = *I; 2644 if (Entry.isMerged()) continue; 2645 if (Entry.isEmpty()) { 2646 Asm->OutStreamer.EmitIntValue(0, Size); 2647 Asm->OutStreamer.EmitIntValue(0, Size); 2648 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", index)); 2649 } else { 2650 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size); 2651 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size); 2652 DIVariable DV(Entry.getVariable()); 2653 Asm->OutStreamer.AddComment("Loc expr size"); 2654 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol(); 2655 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol(); 2656 Asm->EmitLabelDifference(end, begin, 2); 2657 Asm->OutStreamer.EmitLabel(begin); 2658 if (Entry.isInt()) { 2659 DIBasicType BTy(DV.getType()); 2660 if (BTy.Verify() && 2661 (BTy.getEncoding() == dwarf::DW_ATE_signed 2662 || BTy.getEncoding() == dwarf::DW_ATE_signed_char)) { 2663 Asm->OutStreamer.AddComment("DW_OP_consts"); 2664 Asm->EmitInt8(dwarf::DW_OP_consts); 2665 Asm->EmitSLEB128(Entry.getInt()); 2666 } else { 2667 Asm->OutStreamer.AddComment("DW_OP_constu"); 2668 Asm->EmitInt8(dwarf::DW_OP_constu); 2669 Asm->EmitULEB128(Entry.getInt()); 2670 } 2671 } else if (Entry.isLocation()) { 2672 MachineLocation Loc = Entry.getLoc(); 2673 if (!DV.hasComplexAddress()) 2674 // Regular entry. 2675 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2676 else { 2677 // Complex address entry. 2678 unsigned N = DV.getNumAddrElements(); 2679 unsigned i = 0; 2680 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) { 2681 if (Loc.getOffset()) { 2682 i = 2; 2683 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2684 Asm->OutStreamer.AddComment("DW_OP_deref"); 2685 Asm->EmitInt8(dwarf::DW_OP_deref); 2686 Asm->OutStreamer.AddComment("DW_OP_plus_uconst"); 2687 Asm->EmitInt8(dwarf::DW_OP_plus_uconst); 2688 Asm->EmitSLEB128(DV.getAddrElement(1)); 2689 } else { 2690 // If first address element is OpPlus then emit 2691 // DW_OP_breg + Offset instead of DW_OP_reg + Offset. 2692 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1)); 2693 Asm->EmitDwarfRegOp(TLoc, DV.isIndirect()); 2694 i = 2; 2695 } 2696 } else { 2697 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2698 } 2699 2700 // Emit remaining complex address elements. 2701 for (; i < N; ++i) { 2702 uint64_t Element = DV.getAddrElement(i); 2703 if (Element == DIBuilder::OpPlus) { 2704 Asm->EmitInt8(dwarf::DW_OP_plus_uconst); 2705 Asm->EmitULEB128(DV.getAddrElement(++i)); 2706 } else if (Element == DIBuilder::OpDeref) { 2707 if (!Loc.isReg()) 2708 Asm->EmitInt8(dwarf::DW_OP_deref); 2709 } else 2710 llvm_unreachable("unknown Opcode found in complex address"); 2711 } 2712 } 2713 } 2714 // else ... ignore constant fp. There is not any good way to 2715 // to represent them here in dwarf. 2716 Asm->OutStreamer.EmitLabel(end); 2717 } 2718 } 2719} 2720 2721struct SymbolCUSorter { 2722 SymbolCUSorter(const MCStreamer &s) : Streamer(s) {} 2723 const MCStreamer &Streamer; 2724 2725 bool operator() (const SymbolCU &A, const SymbolCU &B) { 2726 unsigned IA = A.Sym ? Streamer.GetSymbolOrder(A.Sym) : 0; 2727 unsigned IB = B.Sym ? Streamer.GetSymbolOrder(B.Sym) : 0; 2728 2729 // Symbols with no order assigned should be placed at the end. 2730 // (e.g. section end labels) 2731 if (IA == 0) 2732 IA = (unsigned)(-1); 2733 if (IB == 0) 2734 IB = (unsigned)(-1); 2735 return IA < IB; 2736 } 2737}; 2738 2739static bool CUSort(const CompileUnit *A, const CompileUnit *B) { 2740 return (A->getUniqueID() < B->getUniqueID()); 2741} 2742 2743struct ArangeSpan { 2744 const MCSymbol *Start, *End; 2745}; 2746 2747// Emit a debug aranges section, containing a CU lookup for any 2748// address we can tie back to a CU. 2749void DwarfDebug::emitDebugARanges() { 2750 // Start the dwarf aranges section. 2751 Asm->OutStreamer 2752 .SwitchSection(Asm->getObjFileLowering().getDwarfARangesSection()); 2753 2754 typedef DenseMap<CompileUnit *, std::vector<ArangeSpan> > SpansType; 2755 2756 SpansType Spans; 2757 2758 // Build a list of sections used. 2759 std::vector<const MCSection *> Sections; 2760 for (SectionMapType::iterator it = SectionMap.begin(); it != SectionMap.end(); 2761 it++) { 2762 const MCSection *Section = it->first; 2763 Sections.push_back(Section); 2764 } 2765 2766 // Sort the sections into order. 2767 // This is only done to ensure consistent output order across different runs. 2768 std::sort(Sections.begin(), Sections.end(), SectionSort); 2769 2770 // Build a set of address spans, sorted by CU. 2771 for (size_t SecIdx=0;SecIdx<Sections.size();SecIdx++) { 2772 const MCSection *Section = Sections[SecIdx]; 2773 SmallVector<SymbolCU, 8> &List = SectionMap[Section]; 2774 if (List.size() < 2) 2775 continue; 2776 2777 // Sort the symbols by offset within the section. 2778 SymbolCUSorter sorter(Asm->OutStreamer); 2779 std::sort(List.begin(), List.end(), sorter); 2780 2781 // If we have no section (e.g. common), just write out 2782 // individual spans for each symbol. 2783 if (Section == NULL) { 2784 for (size_t n = 0; n < List.size(); n++) { 2785 const SymbolCU &Cur = List[n]; 2786 2787 ArangeSpan Span; 2788 Span.Start = Cur.Sym; 2789 Span.End = NULL; 2790 if (Cur.CU) 2791 Spans[Cur.CU].push_back(Span); 2792 } 2793 } else { 2794 // Build spans between each label. 2795 const MCSymbol *StartSym = List[0].Sym; 2796 for (size_t n = 1; n < List.size(); n++) { 2797 const SymbolCU &Prev = List[n - 1]; 2798 const SymbolCU &Cur = List[n]; 2799 2800 // Try and build the longest span we can within the same CU. 2801 if (Cur.CU != Prev.CU) { 2802 ArangeSpan Span; 2803 Span.Start = StartSym; 2804 Span.End = Cur.Sym; 2805 Spans[Prev.CU].push_back(Span); 2806 StartSym = Cur.Sym; 2807 } 2808 } 2809 } 2810 } 2811 2812 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2813 unsigned PtrSize = Asm->getDataLayout().getPointerSize(); 2814 2815 // Build a list of CUs used. 2816 std::vector<CompileUnit *> CUs; 2817 for (SpansType::iterator it = Spans.begin(); it != Spans.end(); it++) { 2818 CompileUnit *CU = it->first; 2819 CUs.push_back(CU); 2820 } 2821 2822 // Sort the CU list (again, to ensure consistent output order). 2823 std::sort(CUs.begin(), CUs.end(), CUSort); 2824 2825 // Emit an arange table for each CU we used. 2826 for (size_t CUIdx=0;CUIdx<CUs.size();CUIdx++) { 2827 CompileUnit *CU = CUs[CUIdx]; 2828 std::vector<ArangeSpan> &List = Spans[CU]; 2829 2830 // Emit size of content not including length itself. 2831 unsigned ContentSize 2832 = sizeof(int16_t) // DWARF ARange version number 2833 + sizeof(int32_t) // Offset of CU in the .debug_info section 2834 + sizeof(int8_t) // Pointer Size (in bytes) 2835 + sizeof(int8_t); // Segment Size (in bytes) 2836 2837 unsigned TupleSize = PtrSize * 2; 2838 2839 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple. 2840 unsigned Padding = 0; 2841 while (((sizeof(int32_t) + ContentSize + Padding) % TupleSize) != 0) 2842 Padding++; 2843 2844 ContentSize += Padding; 2845 ContentSize += (List.size() + 1) * TupleSize; 2846 2847 // For each compile unit, write the list of spans it covers. 2848 Asm->OutStreamer.AddComment("Length of ARange Set"); 2849 Asm->EmitInt32(ContentSize); 2850 Asm->OutStreamer.AddComment("DWARF Arange version number"); 2851 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION); 2852 Asm->OutStreamer.AddComment("Offset Into Debug Info Section"); 2853 Asm->EmitSectionOffset( 2854 Asm->GetTempSymbol(ISec->getLabelBeginName(), CU->getUniqueID()), 2855 DwarfInfoSectionSym); 2856 Asm->OutStreamer.AddComment("Address Size (in bytes)"); 2857 Asm->EmitInt8(PtrSize); 2858 Asm->OutStreamer.AddComment("Segment Size (in bytes)"); 2859 Asm->EmitInt8(0); 2860 2861 for (unsigned n = 0; n < Padding; n++) 2862 Asm->EmitInt8(0xff); 2863 2864 for (unsigned n = 0; n < List.size(); n++) { 2865 const ArangeSpan &Span = List[n]; 2866 Asm->EmitLabelReference(Span.Start, PtrSize); 2867 2868 // Calculate the size as being from the span start to it's end. 2869 if (Span.End) { 2870 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize); 2871 } else { 2872 // For symbols without an end marker (e.g. common), we 2873 // write a single arange entry containing just that one symbol. 2874 uint64_t Size = SymSize[Span.Start]; 2875 if (Size == 0) 2876 Size = 1; 2877 2878 Asm->OutStreamer.EmitIntValue(Size, PtrSize); 2879 } 2880 } 2881 2882 Asm->OutStreamer.AddComment("ARange terminator"); 2883 Asm->OutStreamer.EmitIntValue(0, PtrSize); 2884 Asm->OutStreamer.EmitIntValue(0, PtrSize); 2885 } 2886} 2887 2888// Emit visible names into a debug ranges section. 2889void DwarfDebug::emitDebugRanges() { 2890 // Start the dwarf ranges section. 2891 Asm->OutStreamer 2892 .SwitchSection(Asm->getObjFileLowering().getDwarfRangesSection()); 2893 unsigned char Size = Asm->getDataLayout().getPointerSize(); 2894 for (SmallVectorImpl<const MCSymbol *>::iterator 2895 I = DebugRangeSymbols.begin(), E = DebugRangeSymbols.end(); 2896 I != E; ++I) { 2897 if (*I) 2898 Asm->OutStreamer.EmitSymbolValue(const_cast<MCSymbol*>(*I), Size); 2899 else 2900 Asm->OutStreamer.EmitIntValue(0, Size); 2901 } 2902} 2903 2904// Emit visible names into a debug macinfo section. 2905void DwarfDebug::emitDebugMacInfo() { 2906 if (const MCSection *LineInfo = 2907 Asm->getObjFileLowering().getDwarfMacroInfoSection()) { 2908 // Start the dwarf macinfo section. 2909 Asm->OutStreamer.SwitchSection(LineInfo); 2910 } 2911} 2912 2913// DWARF5 Experimental Separate Dwarf emitters. 2914 2915// This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list, 2916// DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id, 2917// DW_AT_ranges_base, DW_AT_addr_base. 2918CompileUnit *DwarfDebug::constructSkeletonCU(const CompileUnit *CU) { 2919 2920 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit); 2921 CompileUnit *NewCU = new CompileUnit(CU->getUniqueID(), Die, CU->getNode(), 2922 Asm, this, &SkeletonHolder); 2923 2924 NewCU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name, 2925 DICompileUnit(CU->getNode()).getSplitDebugFilename()); 2926 2927 // Relocate to the beginning of the addr_base section, else 0 for the 2928 // beginning of the one for this compile unit. 2929 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2930 NewCU->addLabel(Die, dwarf::DW_AT_GNU_addr_base, dwarf::DW_FORM_sec_offset, 2931 DwarfAddrSectionSym); 2932 else 2933 NewCU->addUInt(Die, dwarf::DW_AT_GNU_addr_base, 2934 dwarf::DW_FORM_sec_offset, 0); 2935 2936 // 2.17.1 requires that we use DW_AT_low_pc for a single entry point 2937 // into an entity. We're using 0, or a NULL label for this. 2938 NewCU->addUInt(Die, dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr, 0); 2939 2940 // DW_AT_stmt_list is a offset of line number information for this 2941 // compile unit in debug_line section. 2942 // FIXME: Should handle multiple compile units. 2943 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2944 NewCU->addLabel(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 2945 DwarfLineSectionSym); 2946 else 2947 NewCU->addUInt(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 0); 2948 2949 if (!CompilationDir.empty()) 2950 NewCU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir); 2951 2952 // Flags to let the linker know we have emitted new style pubnames. 2953 if (GenerateGnuPubSections) { 2954 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2955 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_sec_offset, 2956 Asm->GetTempSymbol("gnu_pubnames", NewCU->getUniqueID())); 2957 else 2958 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_data4, 2959 Asm->GetTempSymbol("gnu_pubnames", NewCU->getUniqueID()), 2960 DwarfGnuPubNamesSectionSym); 2961 2962 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2963 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_sec_offset, 2964 Asm->GetTempSymbol("gnu_pubtypes", NewCU->getUniqueID())); 2965 else 2966 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_data4, 2967 Asm->GetTempSymbol("gnu_pubtypes", NewCU->getUniqueID()), 2968 DwarfGnuPubTypesSectionSym); 2969 } 2970 2971 // Flag if we've emitted any ranges and their location for the compile unit. 2972 if (DebugRangeSymbols.size()) { 2973 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2974 NewCU->addLabel(Die, dwarf::DW_AT_GNU_ranges_base, 2975 dwarf::DW_FORM_sec_offset, DwarfDebugRangeSectionSym); 2976 else 2977 NewCU->addUInt(Die, dwarf::DW_AT_GNU_ranges_base, dwarf::DW_FORM_data4, 2978 0); 2979 } 2980 2981 SkeletonHolder.addUnit(NewCU); 2982 SkeletonCUs.push_back(NewCU); 2983 2984 return NewCU; 2985} 2986 2987void DwarfDebug::emitSkeletonAbbrevs(const MCSection *Section) { 2988 assert(useSplitDwarf() && "No split dwarf debug info?"); 2989 emitAbbrevs(Section, &SkeletonAbbrevs); 2990} 2991 2992// Emit the .debug_info.dwo section for separated dwarf. This contains the 2993// compile units that would normally be in debug_info. 2994void DwarfDebug::emitDebugInfoDWO() { 2995 assert(useSplitDwarf() && "No split dwarf debug info?"); 2996 InfoHolder.emitUnits(this, Asm->getObjFileLowering().getDwarfInfoDWOSection(), 2997 Asm->getObjFileLowering().getDwarfAbbrevDWOSection(), 2998 DwarfAbbrevDWOSectionSym); 2999} 3000 3001// Emit the .debug_abbrev.dwo section for separated dwarf. This contains the 3002// abbreviations for the .debug_info.dwo section. 3003void DwarfDebug::emitDebugAbbrevDWO() { 3004 assert(useSplitDwarf() && "No split dwarf?"); 3005 emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection(), 3006 &Abbreviations); 3007} 3008 3009// Emit the .debug_str.dwo section for separated dwarf. This contains the 3010// string section and is identical in format to traditional .debug_str 3011// sections. 3012void DwarfDebug::emitDebugStrDWO() { 3013 assert(useSplitDwarf() && "No split dwarf?"); 3014 const MCSection *OffSec = Asm->getObjFileLowering() 3015 .getDwarfStrOffDWOSection(); 3016 const MCSymbol *StrSym = DwarfStrSectionSym; 3017 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(), 3018 OffSec, StrSym); 3019} 3020