DwarfDebug.cpp revision 5e195a4c8d8cd4498ab7e0aa16a3b6f273daf457
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 119DIType DbgVariable::getType() const { 120 DIType Ty = Var.getType(); 121 // FIXME: isBlockByrefVariable should be reformulated in terms of complex 122 // addresses instead. 123 if (Var.isBlockByrefVariable()) { 124 /* Byref variables, in Blocks, are declared by the programmer as 125 "SomeType VarName;", but the compiler creates a 126 __Block_byref_x_VarName struct, and gives the variable VarName 127 either the struct, or a pointer to the struct, as its type. This 128 is necessary for various behind-the-scenes things the compiler 129 needs to do with by-reference variables in blocks. 130 131 However, as far as the original *programmer* is concerned, the 132 variable should still have type 'SomeType', as originally declared. 133 134 The following function dives into the __Block_byref_x_VarName 135 struct to find the original type of the variable. This will be 136 passed back to the code generating the type for the Debug 137 Information Entry for the variable 'VarName'. 'VarName' will then 138 have the original type 'SomeType' in its debug information. 139 140 The original type 'SomeType' will be the type of the field named 141 'VarName' inside the __Block_byref_x_VarName struct. 142 143 NOTE: In order for this to not completely fail on the debugger 144 side, the Debug Information Entry for the variable VarName needs to 145 have a DW_AT_location that tells the debugger how to unwind through 146 the pointers and __Block_byref_x_VarName struct to find the actual 147 value of the variable. The function addBlockByrefType does this. */ 148 DIType subType = Ty; 149 uint16_t tag = Ty.getTag(); 150 151 if (tag == dwarf::DW_TAG_pointer_type) 152 subType = DD->resolve(DIDerivedType(Ty).getTypeDerivedFrom()); 153 154 DIArray Elements = DICompositeType(subType).getTypeArray(); 155 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) { 156 DIDerivedType DT = DIDerivedType(Elements.getElement(i)); 157 if (getName() == DT.getName()) 158 return (DD->resolve(DT.getTypeDerivedFrom())); 159 } 160 } 161 return Ty; 162} 163 164} // end llvm namespace 165 166/// Return Dwarf Version by checking module flags. 167static unsigned getDwarfVersionFromModule(const Module *M) { 168 Value *Val = M->getModuleFlag("Dwarf Version"); 169 if (!Val) 170 return dwarf::DWARF_VERSION; 171 return cast<ConstantInt>(Val)->getZExtValue(); 172} 173 174DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M) 175 : Asm(A), MMI(Asm->MMI), FirstCU(0), 176 AbbreviationsSet(InitAbbreviationsSetSize), 177 SourceIdMap(DIEValueAllocator), 178 PrevLabel(NULL), GlobalCUIndexCount(0), 179 InfoHolder(A, &AbbreviationsSet, &Abbreviations, "info_string", 180 DIEValueAllocator), 181 SkeletonAbbrevSet(InitAbbreviationsSetSize), 182 SkeletonHolder(A, &SkeletonAbbrevSet, &SkeletonAbbrevs, "skel_string", 183 DIEValueAllocator) { 184 185 DwarfInfoSectionSym = DwarfAbbrevSectionSym = 0; 186 DwarfStrSectionSym = TextSectionSym = 0; 187 DwarfDebugRangeSectionSym = DwarfDebugLocSectionSym = DwarfLineSectionSym = 0; 188 DwarfAddrSectionSym = 0; 189 DwarfAbbrevDWOSectionSym = DwarfStrDWOSectionSym = 0; 190 FunctionBeginSym = FunctionEndSym = 0; 191 192 // Turn on accelerator tables and older gdb compatibility 193 // for Darwin by default, pubnames by default for non-Darwin, 194 // and handle split dwarf. 195 bool IsDarwin = Triple(A->getTargetTriple()).isOSDarwin(); 196 197 if (DwarfAccelTables == Default) 198 HasDwarfAccelTables = IsDarwin; 199 else 200 HasDwarfAccelTables = DwarfAccelTables == Enable; 201 202 if (SplitDwarf == Default) 203 HasSplitDwarf = false; 204 else 205 HasSplitDwarf = SplitDwarf == Enable; 206 207 if (DwarfPubSections == Default) 208 HasDwarfPubSections = !IsDarwin; 209 else 210 HasDwarfPubSections = DwarfPubSections == Enable; 211 212 DwarfVersion = getDwarfVersionFromModule(MMI->getModule()); 213 214 { 215 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); 216 beginModule(); 217 } 218} 219DwarfDebug::~DwarfDebug() { 220} 221 222// Switch to the specified MCSection and emit an assembler 223// temporary label to it if SymbolStem is specified. 224static MCSymbol *emitSectionSym(AsmPrinter *Asm, const MCSection *Section, 225 const char *SymbolStem = 0) { 226 Asm->OutStreamer.SwitchSection(Section); 227 if (!SymbolStem) return 0; 228 229 MCSymbol *TmpSym = Asm->GetTempSymbol(SymbolStem); 230 Asm->OutStreamer.EmitLabel(TmpSym); 231 return TmpSym; 232} 233 234MCSymbol *DwarfUnits::getStringPoolSym() { 235 return Asm->GetTempSymbol(StringPref); 236} 237 238MCSymbol *DwarfUnits::getStringPoolEntry(StringRef Str) { 239 std::pair<MCSymbol*, unsigned> &Entry = 240 StringPool.GetOrCreateValue(Str).getValue(); 241 if (Entry.first) return Entry.first; 242 243 Entry.second = NextStringPoolNumber++; 244 return Entry.first = Asm->GetTempSymbol(StringPref, Entry.second); 245} 246 247unsigned DwarfUnits::getStringPoolIndex(StringRef Str) { 248 std::pair<MCSymbol*, unsigned> &Entry = 249 StringPool.GetOrCreateValue(Str).getValue(); 250 if (Entry.first) return Entry.second; 251 252 Entry.second = NextStringPoolNumber++; 253 Entry.first = Asm->GetTempSymbol(StringPref, Entry.second); 254 return Entry.second; 255} 256 257unsigned DwarfUnits::getAddrPoolIndex(const MCSymbol *Sym) { 258 return getAddrPoolIndex(MCSymbolRefExpr::Create(Sym, Asm->OutContext)); 259} 260 261unsigned DwarfUnits::getAddrPoolIndex(const MCExpr *Sym) { 262 std::pair<DenseMap<const MCExpr *, unsigned>::iterator, bool> P = 263 AddressPool.insert(std::make_pair(Sym, NextAddrPoolNumber)); 264 if (P.second) 265 ++NextAddrPoolNumber; 266 return P.first->second; 267} 268 269// Define a unique number for the abbreviation. 270// 271void DwarfUnits::assignAbbrevNumber(DIEAbbrev &Abbrev) { 272 // Check the set for priors. 273 DIEAbbrev *InSet = AbbreviationsSet->GetOrInsertNode(&Abbrev); 274 275 // If it's newly added. 276 if (InSet == &Abbrev) { 277 // Add to abbreviation list. 278 Abbreviations->push_back(&Abbrev); 279 280 // Assign the vector position + 1 as its number. 281 Abbrev.setNumber(Abbreviations->size()); 282 } else { 283 // Assign existing abbreviation number. 284 Abbrev.setNumber(InSet->getNumber()); 285 } 286} 287 288static bool isObjCClass(StringRef Name) { 289 return Name.startswith("+") || Name.startswith("-"); 290} 291 292static bool hasObjCCategory(StringRef Name) { 293 if (!isObjCClass(Name)) return false; 294 295 return Name.find(") ") != StringRef::npos; 296} 297 298static void getObjCClassCategory(StringRef In, StringRef &Class, 299 StringRef &Category) { 300 if (!hasObjCCategory(In)) { 301 Class = In.slice(In.find('[') + 1, In.find(' ')); 302 Category = ""; 303 return; 304 } 305 306 Class = In.slice(In.find('[') + 1, In.find('(')); 307 Category = In.slice(In.find('[') + 1, In.find(' ')); 308 return; 309} 310 311static StringRef getObjCMethodName(StringRef In) { 312 return In.slice(In.find(' ') + 1, In.find(']')); 313} 314 315// Helper for sorting sections into a stable output order. 316static bool SectionSort(const MCSection *A, const MCSection *B) { 317 std::string LA = (A ? A->getLabelBeginName() : ""); 318 std::string LB = (B ? B->getLabelBeginName() : ""); 319 return LA < LB; 320} 321 322// Add the various names to the Dwarf accelerator table names. 323// TODO: Determine whether or not we should add names for programs 324// that do not have a DW_AT_name or DW_AT_linkage_name field - this 325// is only slightly different than the lookup of non-standard ObjC names. 326static void addSubprogramNames(CompileUnit *TheCU, DISubprogram SP, 327 DIE* Die) { 328 if (!SP.isDefinition()) return; 329 TheCU->addAccelName(SP.getName(), Die); 330 331 // If the linkage name is different than the name, go ahead and output 332 // that as well into the name table. 333 if (SP.getLinkageName() != "" && SP.getName() != SP.getLinkageName()) 334 TheCU->addAccelName(SP.getLinkageName(), Die); 335 336 // If this is an Objective-C selector name add it to the ObjC accelerator 337 // too. 338 if (isObjCClass(SP.getName())) { 339 StringRef Class, Category; 340 getObjCClassCategory(SP.getName(), Class, Category); 341 TheCU->addAccelObjC(Class, Die); 342 if (Category != "") 343 TheCU->addAccelObjC(Category, Die); 344 // Also add the base method name to the name table. 345 TheCU->addAccelName(getObjCMethodName(SP.getName()), Die); 346 } 347} 348 349/// isSubprogramContext - Return true if Context is either a subprogram 350/// or another context nested inside a subprogram. 351bool DwarfDebug::isSubprogramContext(const MDNode *Context) { 352 if (!Context) 353 return false; 354 DIDescriptor D(Context); 355 if (D.isSubprogram()) 356 return true; 357 if (D.isType()) 358 return isSubprogramContext(resolve(DIType(Context).getContext())); 359 return false; 360} 361 362// Find DIE for the given subprogram and attach appropriate DW_AT_low_pc 363// and DW_AT_high_pc attributes. If there are global variables in this 364// scope then create and insert DIEs for these variables. 365DIE *DwarfDebug::updateSubprogramScopeDIE(CompileUnit *SPCU, 366 const MDNode *SPNode) { 367 DIE *SPDie = SPCU->getDIE(SPNode); 368 369 assert(SPDie && "Unable to find subprogram DIE!"); 370 DISubprogram SP(SPNode); 371 372 // If we're updating an abstract DIE, then we will be adding the children and 373 // object pointer later on. But what we don't want to do is process the 374 // concrete DIE twice. 375 if (DIE *AbsSPDIE = AbstractSPDies.lookup(SPNode)) { 376 // Pick up abstract subprogram DIE. 377 SPDie = new DIE(dwarf::DW_TAG_subprogram); 378 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_abstract_origin, 379 dwarf::DW_FORM_ref4, AbsSPDIE); 380 SPCU->addDie(SPDie); 381 } else { 382 DISubprogram SPDecl = SP.getFunctionDeclaration(); 383 if (!SPDecl.isSubprogram()) { 384 // There is not any need to generate specification DIE for a function 385 // defined at compile unit level. If a function is defined inside another 386 // function then gdb prefers the definition at top level and but does not 387 // expect specification DIE in parent function. So avoid creating 388 // specification DIE for a function defined inside a function. 389 if (SP.isDefinition() && !SP.getContext().isCompileUnit() && 390 !SP.getContext().isFile() && 391 !isSubprogramContext(SP.getContext())) { 392 SPCU->addFlag(SPDie, dwarf::DW_AT_declaration); 393 394 // Add arguments. 395 DICompositeType SPTy = SP.getType(); 396 DIArray Args = SPTy.getTypeArray(); 397 uint16_t SPTag = SPTy.getTag(); 398 if (SPTag == dwarf::DW_TAG_subroutine_type) 399 for (unsigned i = 1, N = Args.getNumElements(); i < N; ++i) { 400 DIE *Arg = new DIE(dwarf::DW_TAG_formal_parameter); 401 DIType ATy = DIType(Args.getElement(i)); 402 SPCU->addType(Arg, ATy); 403 if (ATy.isArtificial()) 404 SPCU->addFlag(Arg, dwarf::DW_AT_artificial); 405 if (ATy.isObjectPointer()) 406 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_object_pointer, 407 dwarf::DW_FORM_ref4, Arg); 408 SPDie->addChild(Arg); 409 } 410 DIE *SPDeclDie = SPDie; 411 SPDie = new DIE(dwarf::DW_TAG_subprogram); 412 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_specification, 413 dwarf::DW_FORM_ref4, SPDeclDie); 414 SPCU->addDie(SPDie); 415 } 416 } 417 } 418 419 SPCU->addLabelAddress(SPDie, dwarf::DW_AT_low_pc, 420 Asm->GetTempSymbol("func_begin", 421 Asm->getFunctionNumber())); 422 SPCU->addLabelAddress(SPDie, dwarf::DW_AT_high_pc, 423 Asm->GetTempSymbol("func_end", 424 Asm->getFunctionNumber())); 425 const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo(); 426 MachineLocation Location(RI->getFrameRegister(*Asm->MF)); 427 SPCU->addAddress(SPDie, dwarf::DW_AT_frame_base, Location); 428 429 // Add name to the name table, we do this here because we're guaranteed 430 // to have concrete versions of our DW_TAG_subprogram nodes. 431 addSubprogramNames(SPCU, SP, SPDie); 432 433 return SPDie; 434} 435 436/// Check whether we should create a DIE for the given Scope, return true 437/// if we don't create a DIE (the corresponding DIE is null). 438bool DwarfDebug::isLexicalScopeDIENull(LexicalScope *Scope) { 439 if (Scope->isAbstractScope()) 440 return false; 441 442 // We don't create a DIE if there is no Range. 443 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 444 if (Ranges.empty()) 445 return true; 446 447 if (Ranges.size() > 1) 448 return false; 449 450 // We don't create a DIE if we have a single Range and the end label 451 // is null. 452 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 453 MCSymbol *End = getLabelAfterInsn(RI->second); 454 return !End; 455} 456 457// Construct new DW_TAG_lexical_block for this scope and attach 458// DW_AT_low_pc/DW_AT_high_pc labels. 459DIE *DwarfDebug::constructLexicalScopeDIE(CompileUnit *TheCU, 460 LexicalScope *Scope) { 461 if (isLexicalScopeDIENull(Scope)) 462 return 0; 463 464 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_lexical_block); 465 if (Scope->isAbstractScope()) 466 return ScopeDIE; 467 468 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 469 // If we have multiple ranges, emit them into the range section. 470 if (Ranges.size() > 1) { 471 // .debug_range section has not been laid out yet. Emit offset in 472 // .debug_range as a uint, size 4, for now. emitDIE will handle 473 // DW_AT_ranges appropriately. 474 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_ranges, dwarf::DW_FORM_data4, 475 DebugRangeSymbols.size() 476 * Asm->getDataLayout().getPointerSize()); 477 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 478 RE = Ranges.end(); RI != RE; ++RI) { 479 DebugRangeSymbols.push_back(getLabelBeforeInsn(RI->first)); 480 DebugRangeSymbols.push_back(getLabelAfterInsn(RI->second)); 481 } 482 483 // Terminate the range list. 484 DebugRangeSymbols.push_back(NULL); 485 DebugRangeSymbols.push_back(NULL); 486 return ScopeDIE; 487 } 488 489 // Construct the address range for this DIE. 490 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 491 MCSymbol *Start = getLabelBeforeInsn(RI->first); 492 MCSymbol *End = getLabelAfterInsn(RI->second); 493 assert(End && "End label should not be null!"); 494 495 assert(Start->isDefined() && "Invalid starting label for an inlined scope!"); 496 assert(End->isDefined() && "Invalid end label for an inlined scope!"); 497 498 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_low_pc, Start); 499 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_high_pc, End); 500 501 return ScopeDIE; 502} 503 504// This scope represents inlined body of a function. Construct DIE to 505// represent this concrete inlined copy of the function. 506DIE *DwarfDebug::constructInlinedScopeDIE(CompileUnit *TheCU, 507 LexicalScope *Scope) { 508 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); 509 assert(Ranges.empty() == false && 510 "LexicalScope does not have instruction markers!"); 511 512 if (!Scope->getScopeNode()) 513 return NULL; 514 DIScope DS(Scope->getScopeNode()); 515 DISubprogram InlinedSP = getDISubprogram(DS); 516 DIE *OriginDIE = TheCU->getDIE(InlinedSP); 517 if (!OriginDIE) { 518 DEBUG(dbgs() << "Unable to find original DIE for an inlined subprogram."); 519 return NULL; 520 } 521 522 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_inlined_subroutine); 523 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_abstract_origin, 524 dwarf::DW_FORM_ref4, OriginDIE); 525 526 if (Ranges.size() > 1) { 527 // .debug_range section has not been laid out yet. Emit offset in 528 // .debug_range as a uint, size 4, for now. emitDIE will handle 529 // DW_AT_ranges appropriately. 530 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_ranges, dwarf::DW_FORM_data4, 531 DebugRangeSymbols.size() 532 * Asm->getDataLayout().getPointerSize()); 533 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 534 RE = Ranges.end(); RI != RE; ++RI) { 535 DebugRangeSymbols.push_back(getLabelBeforeInsn(RI->first)); 536 DebugRangeSymbols.push_back(getLabelAfterInsn(RI->second)); 537 } 538 DebugRangeSymbols.push_back(NULL); 539 DebugRangeSymbols.push_back(NULL); 540 } else { 541 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); 542 MCSymbol *StartLabel = getLabelBeforeInsn(RI->first); 543 MCSymbol *EndLabel = getLabelAfterInsn(RI->second); 544 545 if (StartLabel == 0 || EndLabel == 0) 546 llvm_unreachable("Unexpected Start and End labels for an inlined scope!"); 547 548 assert(StartLabel->isDefined() && 549 "Invalid starting label for an inlined scope!"); 550 assert(EndLabel->isDefined() && "Invalid end label for an inlined scope!"); 551 552 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_low_pc, StartLabel); 553 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_high_pc, EndLabel); 554 } 555 556 InlinedSubprogramDIEs.insert(OriginDIE); 557 558 // Add the call site information to the DIE. 559 DILocation DL(Scope->getInlinedAt()); 560 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_file, 0, 561 getOrCreateSourceID(DL.getFilename(), DL.getDirectory(), 562 TheCU->getUniqueID())); 563 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_line, 0, DL.getLineNumber()); 564 565 // Add name to the name table, we do this here because we're guaranteed 566 // to have concrete versions of our DW_TAG_inlined_subprogram nodes. 567 addSubprogramNames(TheCU, InlinedSP, ScopeDIE); 568 569 return ScopeDIE; 570} 571 572DIE *DwarfDebug::createScopeChildrenDIE(CompileUnit *TheCU, LexicalScope *Scope, 573 SmallVectorImpl<DIE*> &Children) { 574 DIE *ObjectPointer = NULL; 575 576 // Collect arguments for current function. 577 if (LScopes.isCurrentFunctionScope(Scope)) 578 for (unsigned i = 0, N = CurrentFnArguments.size(); i < N; ++i) 579 if (DbgVariable *ArgDV = CurrentFnArguments[i]) 580 if (DIE *Arg = 581 TheCU->constructVariableDIE(ArgDV, Scope->isAbstractScope())) { 582 Children.push_back(Arg); 583 if (ArgDV->isObjectPointer()) ObjectPointer = Arg; 584 } 585 586 // Collect lexical scope children first. 587 const SmallVectorImpl<DbgVariable *> &Variables =ScopeVariables.lookup(Scope); 588 for (unsigned i = 0, N = Variables.size(); i < N; ++i) 589 if (DIE *Variable = 590 TheCU->constructVariableDIE(Variables[i], Scope->isAbstractScope())) { 591 Children.push_back(Variable); 592 if (Variables[i]->isObjectPointer()) ObjectPointer = Variable; 593 } 594 const SmallVectorImpl<LexicalScope *> &Scopes = Scope->getChildren(); 595 for (unsigned j = 0, M = Scopes.size(); j < M; ++j) 596 if (DIE *Nested = constructScopeDIE(TheCU, Scopes[j])) 597 Children.push_back(Nested); 598 return ObjectPointer; 599} 600 601// Construct a DIE for this scope. 602DIE *DwarfDebug::constructScopeDIE(CompileUnit *TheCU, LexicalScope *Scope) { 603 if (!Scope || !Scope->getScopeNode()) 604 return NULL; 605 606 DIScope DS(Scope->getScopeNode()); 607 608 SmallVector<DIE *, 8> Children; 609 DIE *ObjectPointer = NULL; 610 bool ChildrenCreated = false; 611 612 // We try to create the scope DIE first, then the children DIEs. This will 613 // avoid creating un-used children then removing them later when we find out 614 // the scope DIE is null. 615 DIE *ScopeDIE = NULL; 616 if (Scope->getInlinedAt()) 617 ScopeDIE = constructInlinedScopeDIE(TheCU, Scope); 618 else if (DS.isSubprogram()) { 619 ProcessedSPNodes.insert(DS); 620 if (Scope->isAbstractScope()) { 621 ScopeDIE = TheCU->getDIE(DS); 622 // Note down abstract DIE. 623 if (ScopeDIE) 624 AbstractSPDies.insert(std::make_pair(DS, ScopeDIE)); 625 } 626 else 627 ScopeDIE = updateSubprogramScopeDIE(TheCU, DS); 628 } 629 else { 630 // Early exit when we know the scope DIE is going to be null. 631 if (isLexicalScopeDIENull(Scope)) 632 return NULL; 633 634 // We create children here when we know the scope DIE is not going to be 635 // null and the children will be added to the scope DIE. 636 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children); 637 ChildrenCreated = true; 638 639 // There is no need to emit empty lexical block DIE. 640 std::pair<ImportedEntityMap::const_iterator, 641 ImportedEntityMap::const_iterator> Range = std::equal_range( 642 ScopesWithImportedEntities.begin(), ScopesWithImportedEntities.end(), 643 std::pair<const MDNode *, const MDNode *>(DS, (const MDNode*)0), 644 less_first()); 645 if (Children.empty() && Range.first == Range.second) 646 return NULL; 647 ScopeDIE = constructLexicalScopeDIE(TheCU, Scope); 648 assert(ScopeDIE && "Scope DIE should not be null."); 649 for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second; 650 ++i) 651 constructImportedEntityDIE(TheCU, i->second, ScopeDIE); 652 } 653 654 if (!ScopeDIE) { 655 assert(Children.empty() && 656 "We create children only when the scope DIE is not null."); 657 return NULL; 658 } 659 if (!ChildrenCreated) 660 // We create children when the scope DIE is not null. 661 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children); 662 663 // Add children 664 for (SmallVectorImpl<DIE *>::iterator I = Children.begin(), 665 E = Children.end(); I != E; ++I) 666 ScopeDIE->addChild(*I); 667 668 if (DS.isSubprogram() && ObjectPointer != NULL) 669 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, 670 dwarf::DW_FORM_ref4, 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, 830 const MDNode *N) { 831 CompileUnit *&CURef = SPMap[N]; 832 if (CURef) 833 return; 834 CURef = TheCU; 835 836 DISubprogram SP(N); 837 if (!SP.isDefinition()) 838 // This is a method declaration which will be handled while constructing 839 // class type. 840 return; 841 842 DIE *SubprogramDie = TheCU->getOrCreateSubprogramDIE(SP); 843 844 // Expose as a global name. 845 TheCU->addGlobalName(SP.getName(), SubprogramDie); 846} 847 848void DwarfDebug::constructImportedEntityDIE(CompileUnit *TheCU, 849 const MDNode *N) { 850 DIImportedEntity Module(N); 851 if (!Module.Verify()) 852 return; 853 if (DIE *D = TheCU->getOrCreateContextDIE(Module.getContext())) 854 constructImportedEntityDIE(TheCU, Module, D); 855} 856 857void DwarfDebug::constructImportedEntityDIE(CompileUnit *TheCU, const MDNode *N, 858 DIE *Context) { 859 DIImportedEntity Module(N); 860 if (!Module.Verify()) 861 return; 862 return constructImportedEntityDIE(TheCU, Module, Context); 863} 864 865void DwarfDebug::constructImportedEntityDIE(CompileUnit *TheCU, 866 const DIImportedEntity &Module, 867 DIE *Context) { 868 assert(Module.Verify() && 869 "Use one of the MDNode * overloads to handle invalid metadata"); 870 assert(Context && "Should always have a context for an imported_module"); 871 DIE *IMDie = new DIE(Module.getTag()); 872 TheCU->insertDIE(Module, IMDie); 873 DIE *EntityDie; 874 DIDescriptor Entity = Module.getEntity(); 875 if (Entity.isNameSpace()) 876 EntityDie = TheCU->getOrCreateNameSpace(DINameSpace(Entity)); 877 else if (Entity.isSubprogram()) 878 EntityDie = TheCU->getOrCreateSubprogramDIE(DISubprogram(Entity)); 879 else if (Entity.isType()) 880 EntityDie = TheCU->getOrCreateTypeDIE(DIType(Entity)); 881 else 882 EntityDie = TheCU->getDIE(Entity); 883 unsigned FileID = getOrCreateSourceID(Module.getContext().getFilename(), 884 Module.getContext().getDirectory(), 885 TheCU->getUniqueID()); 886 TheCU->addUInt(IMDie, dwarf::DW_AT_decl_file, 0, FileID); 887 TheCU->addUInt(IMDie, dwarf::DW_AT_decl_line, 0, Module.getLineNumber()); 888 TheCU->addDIEEntry(IMDie, dwarf::DW_AT_import, dwarf::DW_FORM_ref4, 889 EntityDie); 890 StringRef Name = Module.getName(); 891 if (!Name.empty()) 892 TheCU->addString(IMDie, dwarf::DW_AT_name, Name); 893 Context->addChild(IMDie); 894} 895 896// Emit all Dwarf sections that should come prior to the content. Create 897// global DIEs and emit initial debug info sections. This is invoked by 898// the target AsmPrinter. 899void DwarfDebug::beginModule() { 900 if (DisableDebugInfoPrinting) 901 return; 902 903 const Module *M = MMI->getModule(); 904 905 // If module has named metadata anchors then use them, otherwise scan the 906 // module using debug info finder to collect debug info. 907 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu"); 908 if (!CU_Nodes) 909 return; 910 TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes); 911 912 // Emit initial sections so we can reference labels later. 913 emitSectionLabels(); 914 915 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) { 916 DICompileUnit CUNode(CU_Nodes->getOperand(i)); 917 CompileUnit *CU = constructCompileUnit(CUNode); 918 DIArray ImportedEntities = CUNode.getImportedEntities(); 919 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i) 920 ScopesWithImportedEntities.push_back(std::make_pair( 921 DIImportedEntity(ImportedEntities.getElement(i)).getContext(), 922 ImportedEntities.getElement(i))); 923 std::sort(ScopesWithImportedEntities.begin(), 924 ScopesWithImportedEntities.end(), less_first()); 925 DIArray GVs = CUNode.getGlobalVariables(); 926 for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i) 927 CU->createGlobalVariableDIE(GVs.getElement(i)); 928 DIArray SPs = CUNode.getSubprograms(); 929 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) 930 constructSubprogramDIE(CU, SPs.getElement(i)); 931 DIArray EnumTypes = CUNode.getEnumTypes(); 932 for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i) 933 CU->getOrCreateTypeDIE(EnumTypes.getElement(i)); 934 DIArray RetainedTypes = CUNode.getRetainedTypes(); 935 for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i) 936 CU->getOrCreateTypeDIE(RetainedTypes.getElement(i)); 937 // Emit imported_modules last so that the relevant context is already 938 // available. 939 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i) 940 constructImportedEntityDIE(CU, ImportedEntities.getElement(i)); 941 } 942 943 // Tell MMI that we have debug info. 944 MMI->setDebugInfoAvailability(true); 945 946 // Prime section data. 947 SectionMap[Asm->getObjFileLowering().getTextSection()]; 948} 949 950// Attach DW_AT_inline attribute with inlined subprogram DIEs. 951void DwarfDebug::computeInlinedDIEs() { 952 // Attach DW_AT_inline attribute with inlined subprogram DIEs. 953 for (SmallPtrSet<DIE *, 4>::iterator AI = InlinedSubprogramDIEs.begin(), 954 AE = InlinedSubprogramDIEs.end(); AI != AE; ++AI) { 955 DIE *ISP = *AI; 956 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, 0, dwarf::DW_INL_inlined); 957 } 958 for (DenseMap<const MDNode *, DIE *>::iterator AI = AbstractSPDies.begin(), 959 AE = AbstractSPDies.end(); AI != AE; ++AI) { 960 DIE *ISP = AI->second; 961 if (InlinedSubprogramDIEs.count(ISP)) 962 continue; 963 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, 0, dwarf::DW_INL_inlined); 964 } 965} 966 967// Collect info for variables that were optimized out. 968void DwarfDebug::collectDeadVariables() { 969 const Module *M = MMI->getModule(); 970 DenseMap<const MDNode *, LexicalScope *> DeadFnScopeMap; 971 972 if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) { 973 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) { 974 DICompileUnit TheCU(CU_Nodes->getOperand(i)); 975 DIArray Subprograms = TheCU.getSubprograms(); 976 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) { 977 DISubprogram SP(Subprograms.getElement(i)); 978 if (ProcessedSPNodes.count(SP) != 0) continue; 979 if (!SP.isSubprogram()) continue; 980 if (!SP.isDefinition()) continue; 981 DIArray Variables = SP.getVariables(); 982 if (Variables.getNumElements() == 0) continue; 983 984 LexicalScope *Scope = 985 new LexicalScope(NULL, DIDescriptor(SP), NULL, false); 986 DeadFnScopeMap[SP] = Scope; 987 988 // Construct subprogram DIE and add variables DIEs. 989 CompileUnit *SPCU = CUMap.lookup(TheCU); 990 assert(SPCU && "Unable to find Compile Unit!"); 991 constructSubprogramDIE(SPCU, SP); 992 DIE *ScopeDIE = SPCU->getDIE(SP); 993 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) { 994 DIVariable DV(Variables.getElement(vi)); 995 if (!DV.isVariable()) continue; 996 DbgVariable NewVar(DV, NULL, this); 997 if (DIE *VariableDIE = 998 SPCU->constructVariableDIE(&NewVar, Scope->isAbstractScope())) 999 ScopeDIE->addChild(VariableDIE); 1000 } 1001 } 1002 } 1003 } 1004 DeleteContainerSeconds(DeadFnScopeMap); 1005} 1006 1007// Type Signature [7.27] and ODR Hash code. 1008 1009/// \brief Grabs the string in whichever attribute is passed in and returns 1010/// a reference to it. Returns "" if the attribute doesn't exist. 1011static StringRef getDIEStringAttr(DIE *Die, unsigned Attr) { 1012 DIEValue *V = Die->findAttribute(Attr); 1013 1014 if (DIEString *S = dyn_cast_or_null<DIEString>(V)) 1015 return S->getString(); 1016 1017 return StringRef(""); 1018} 1019 1020/// Return true if the current DIE is contained within an anonymous namespace. 1021static bool isContainedInAnonNamespace(DIE *Die) { 1022 DIE *Parent = Die->getParent(); 1023 1024 while (Parent) { 1025 if (Parent->getTag() == dwarf::DW_TAG_namespace && 1026 getDIEStringAttr(Parent, dwarf::DW_AT_name) == "") 1027 return true; 1028 Parent = Parent->getParent(); 1029 } 1030 1031 return false; 1032} 1033 1034/// Test if the current CU language is C++ and that we have 1035/// a named type that is not contained in an anonymous namespace. 1036static bool shouldAddODRHash(CompileUnit *CU, DIE *Die) { 1037 return CU->getLanguage() == dwarf::DW_LANG_C_plus_plus && 1038 getDIEStringAttr(Die, dwarf::DW_AT_name) != "" && 1039 !isContainedInAnonNamespace(Die); 1040} 1041 1042void DwarfDebug::finalizeModuleInfo() { 1043 // Collect info for variables that were optimized out. 1044 collectDeadVariables(); 1045 1046 // Attach DW_AT_inline attribute with inlined subprogram DIEs. 1047 computeInlinedDIEs(); 1048 1049 // Split out type units and conditionally add an ODR tag to the split 1050 // out type. 1051 // FIXME: Do type splitting. 1052 for (unsigned i = 0, e = TypeUnits.size(); i != e; ++i) { 1053 DIE *Die = TypeUnits[i]; 1054 DIEHash Hash; 1055 // If we've requested ODR hashes and it's applicable for an ODR hash then 1056 // add the ODR signature now. 1057 // FIXME: This should be added onto the type unit, not the type, but this 1058 // works as an intermediate stage. 1059 if (GenerateODRHash && shouldAddODRHash(CUMap.begin()->second, Die)) 1060 CUMap.begin()->second->addUInt(Die, dwarf::DW_AT_GNU_odr_signature, 1061 dwarf::DW_FORM_data8, 1062 Hash.computeDIEODRSignature(Die)); 1063 } 1064 1065 // Handle anything that needs to be done on a per-cu basis. 1066 for (DenseMap<const MDNode *, CompileUnit *>::iterator CUI = CUMap.begin(), 1067 CUE = CUMap.end(); 1068 CUI != CUE; ++CUI) { 1069 CompileUnit *TheCU = CUI->second; 1070 // Emit DW_AT_containing_type attribute to connect types with their 1071 // vtable holding type. 1072 TheCU->constructContainingTypeDIEs(); 1073 1074 // If we're splitting the dwarf out now that we've got the entire 1075 // CU then construct a skeleton CU based upon it. 1076 if (useSplitDwarf()) { 1077 uint64_t ID = 0; 1078 if (GenerateCUHash) { 1079 DIEHash CUHash; 1080 ID = CUHash.computeCUSignature(TheCU->getCUDie()); 1081 } 1082 // This should be a unique identifier when we want to build .dwp files. 1083 TheCU->addUInt(TheCU->getCUDie(), dwarf::DW_AT_GNU_dwo_id, 1084 dwarf::DW_FORM_data8, ID); 1085 // Now construct the skeleton CU associated. 1086 CompileUnit *SkCU = constructSkeletonCU(TheCU); 1087 // This should be a unique identifier when we want to build .dwp files. 1088 SkCU->addUInt(SkCU->getCUDie(), dwarf::DW_AT_GNU_dwo_id, 1089 dwarf::DW_FORM_data8, ID); 1090 } 1091 } 1092 1093 // Compute DIE offsets and sizes. 1094 InfoHolder.computeSizeAndOffsets(); 1095 if (useSplitDwarf()) 1096 SkeletonHolder.computeSizeAndOffsets(); 1097} 1098 1099void DwarfDebug::endSections() { 1100 // Filter labels by section. 1101 for (size_t n = 0; n < ArangeLabels.size(); n++) { 1102 const SymbolCU &SCU = ArangeLabels[n]; 1103 if (SCU.Sym->isInSection()) { 1104 // Make a note of this symbol and it's section. 1105 const MCSection *Section = &SCU.Sym->getSection(); 1106 if (!Section->getKind().isMetadata()) 1107 SectionMap[Section].push_back(SCU); 1108 } else { 1109 // Some symbols (e.g. common/bss on mach-o) can have no section but still 1110 // appear in the output. This sucks as we rely on sections to build 1111 // arange spans. We can do it without, but it's icky. 1112 SectionMap[NULL].push_back(SCU); 1113 } 1114 } 1115 1116 // Build a list of sections used. 1117 std::vector<const MCSection *> Sections; 1118 for (SectionMapType::iterator it = SectionMap.begin(); it != SectionMap.end(); 1119 it++) { 1120 const MCSection *Section = it->first; 1121 Sections.push_back(Section); 1122 } 1123 1124 // Sort the sections into order. 1125 // This is only done to ensure consistent output order across different runs. 1126 std::sort(Sections.begin(), Sections.end(), SectionSort); 1127 1128 // Add terminating symbols for each section. 1129 for (unsigned ID=0;ID<Sections.size();ID++) { 1130 const MCSection *Section = Sections[ID]; 1131 MCSymbol *Sym = NULL; 1132 1133 if (Section) { 1134 // We can't call MCSection::getLabelEndName, as it's only safe to do so 1135 // if we know the section name up-front. For user-created sections, the resulting 1136 // label may not be valid to use as a label. (section names can use a greater 1137 // set of characters on some systems) 1138 Sym = Asm->GetTempSymbol("debug_end", ID); 1139 Asm->OutStreamer.SwitchSection(Section); 1140 Asm->OutStreamer.EmitLabel(Sym); 1141 } 1142 1143 // Insert a final terminator. 1144 SectionMap[Section].push_back(SymbolCU(NULL, Sym)); 1145 } 1146} 1147 1148// Emit all Dwarf sections that should come after the content. 1149void DwarfDebug::endModule() { 1150 1151 if (!FirstCU) return; 1152 1153 // End any existing sections. 1154 // TODO: Does this need to happen? 1155 endSections(); 1156 1157 // Finalize the debug info for the module. 1158 finalizeModuleInfo(); 1159 1160 if (!useSplitDwarf()) { 1161 emitDebugStr(); 1162 1163 // Emit all the DIEs into a debug info section. 1164 emitDebugInfo(); 1165 1166 // Corresponding abbreviations into a abbrev section. 1167 emitAbbreviations(); 1168 1169 // Emit info into a debug loc section. 1170 emitDebugLoc(); 1171 1172 // Emit info into a debug aranges section. 1173 emitDebugARanges(); 1174 1175 // Emit info into a debug ranges section. 1176 emitDebugRanges(); 1177 1178 // Emit info into a debug macinfo section. 1179 emitDebugMacInfo(); 1180 1181 } else { 1182 // TODO: Fill this in for separated debug sections and separate 1183 // out information into new sections. 1184 emitDebugStr(); 1185 if (useSplitDwarf()) 1186 emitDebugStrDWO(); 1187 1188 // Emit the debug info section and compile units. 1189 emitDebugInfo(); 1190 emitDebugInfoDWO(); 1191 1192 // Corresponding abbreviations into a abbrev section. 1193 emitAbbreviations(); 1194 emitDebugAbbrevDWO(); 1195 1196 // Emit info into a debug loc section. 1197 emitDebugLoc(); 1198 1199 // Emit info into a debug aranges section. 1200 emitDebugARanges(); 1201 1202 // Emit info into a debug ranges section. 1203 emitDebugRanges(); 1204 1205 // Emit info into a debug macinfo section. 1206 emitDebugMacInfo(); 1207 1208 // Emit DWO addresses. 1209 InfoHolder.emitAddresses(Asm->getObjFileLowering().getDwarfAddrSection()); 1210 1211 } 1212 1213 // Emit info into the dwarf accelerator table sections. 1214 if (useDwarfAccelTables()) { 1215 emitAccelNames(); 1216 emitAccelObjC(); 1217 emitAccelNamespaces(); 1218 emitAccelTypes(); 1219 } 1220 1221 // Emit the pubnames and pubtypes sections if requested. 1222 if (HasDwarfPubSections) { 1223 emitDebugPubNames(GenerateGnuPubSections); 1224 emitDebugPubTypes(GenerateGnuPubSections); 1225 } 1226 1227 // clean up. 1228 SPMap.clear(); 1229 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 1230 E = CUMap.end(); I != E; ++I) 1231 delete I->second; 1232 1233 for (SmallVectorImpl<CompileUnit *>::iterator I = SkeletonCUs.begin(), 1234 E = SkeletonCUs.end(); I != E; ++I) 1235 delete *I; 1236 1237 // Reset these for the next Module if we have one. 1238 FirstCU = NULL; 1239} 1240 1241// Find abstract variable, if any, associated with Var. 1242DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &DV, 1243 DebugLoc ScopeLoc) { 1244 LLVMContext &Ctx = DV->getContext(); 1245 // More then one inlined variable corresponds to one abstract variable. 1246 DIVariable Var = cleanseInlinedVariable(DV, Ctx); 1247 DbgVariable *AbsDbgVariable = AbstractVariables.lookup(Var); 1248 if (AbsDbgVariable) 1249 return AbsDbgVariable; 1250 1251 LexicalScope *Scope = LScopes.findAbstractScope(ScopeLoc.getScope(Ctx)); 1252 if (!Scope) 1253 return NULL; 1254 1255 AbsDbgVariable = new DbgVariable(Var, NULL, this); 1256 addScopeVariable(Scope, AbsDbgVariable); 1257 AbstractVariables[Var] = AbsDbgVariable; 1258 return AbsDbgVariable; 1259} 1260 1261// If Var is a current function argument then add it to CurrentFnArguments list. 1262bool DwarfDebug::addCurrentFnArgument(const MachineFunction *MF, 1263 DbgVariable *Var, LexicalScope *Scope) { 1264 if (!LScopes.isCurrentFunctionScope(Scope)) 1265 return false; 1266 DIVariable DV = Var->getVariable(); 1267 if (DV.getTag() != dwarf::DW_TAG_arg_variable) 1268 return false; 1269 unsigned ArgNo = DV.getArgNumber(); 1270 if (ArgNo == 0) 1271 return false; 1272 1273 size_t Size = CurrentFnArguments.size(); 1274 if (Size == 0) 1275 CurrentFnArguments.resize(MF->getFunction()->arg_size()); 1276 // llvm::Function argument size is not good indicator of how many 1277 // arguments does the function have at source level. 1278 if (ArgNo > Size) 1279 CurrentFnArguments.resize(ArgNo * 2); 1280 CurrentFnArguments[ArgNo - 1] = Var; 1281 return true; 1282} 1283 1284// Collect variable information from side table maintained by MMI. 1285void 1286DwarfDebug::collectVariableInfoFromMMITable(const MachineFunction *MF, 1287 SmallPtrSet<const MDNode *, 16> &Processed) { 1288 MachineModuleInfo::VariableDbgInfoMapTy &VMap = MMI->getVariableDbgInfo(); 1289 for (MachineModuleInfo::VariableDbgInfoMapTy::iterator VI = VMap.begin(), 1290 VE = VMap.end(); VI != VE; ++VI) { 1291 const MDNode *Var = VI->first; 1292 if (!Var) continue; 1293 Processed.insert(Var); 1294 DIVariable DV(Var); 1295 const std::pair<unsigned, DebugLoc> &VP = VI->second; 1296 1297 LexicalScope *Scope = LScopes.findLexicalScope(VP.second); 1298 1299 // If variable scope is not found then skip this variable. 1300 if (Scope == 0) 1301 continue; 1302 1303 DbgVariable *AbsDbgVariable = findAbstractVariable(DV, VP.second); 1304 DbgVariable *RegVar = new DbgVariable(DV, AbsDbgVariable, this); 1305 RegVar->setFrameIndex(VP.first); 1306 if (!addCurrentFnArgument(MF, RegVar, Scope)) 1307 addScopeVariable(Scope, RegVar); 1308 if (AbsDbgVariable) 1309 AbsDbgVariable->setFrameIndex(VP.first); 1310 } 1311} 1312 1313// Return true if debug value, encoded by DBG_VALUE instruction, is in a 1314// defined reg. 1315static bool isDbgValueInDefinedReg(const MachineInstr *MI) { 1316 assert(MI->isDebugValue() && "Invalid DBG_VALUE machine instruction!"); 1317 return MI->getNumOperands() == 3 && 1318 MI->getOperand(0).isReg() && MI->getOperand(0).getReg() && 1319 (MI->getOperand(1).isImm() || 1320 (MI->getOperand(1).isReg() && MI->getOperand(1).getReg() == 0U)); 1321} 1322 1323// Get .debug_loc entry for the instruction range starting at MI. 1324static DotDebugLocEntry getDebugLocEntry(AsmPrinter *Asm, 1325 const MCSymbol *FLabel, 1326 const MCSymbol *SLabel, 1327 const MachineInstr *MI) { 1328 const MDNode *Var = MI->getOperand(MI->getNumOperands() - 1).getMetadata(); 1329 1330 assert(MI->getNumOperands() == 3); 1331 if (MI->getOperand(0).isReg()) { 1332 MachineLocation MLoc; 1333 // If the second operand is an immediate, this is a 1334 // register-indirect address. 1335 if (!MI->getOperand(1).isImm()) 1336 MLoc.set(MI->getOperand(0).getReg()); 1337 else 1338 MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm()); 1339 return DotDebugLocEntry(FLabel, SLabel, MLoc, Var); 1340 } 1341 if (MI->getOperand(0).isImm()) 1342 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getImm()); 1343 if (MI->getOperand(0).isFPImm()) 1344 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getFPImm()); 1345 if (MI->getOperand(0).isCImm()) 1346 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getCImm()); 1347 1348 llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!"); 1349} 1350 1351// Find variables for each lexical scope. 1352void 1353DwarfDebug::collectVariableInfo(const MachineFunction *MF, 1354 SmallPtrSet<const MDNode *, 16> &Processed) { 1355 1356 // Grab the variable info that was squirreled away in the MMI side-table. 1357 collectVariableInfoFromMMITable(MF, Processed); 1358 1359 for (SmallVectorImpl<const MDNode*>::const_iterator 1360 UVI = UserVariables.begin(), UVE = UserVariables.end(); UVI != UVE; 1361 ++UVI) { 1362 const MDNode *Var = *UVI; 1363 if (Processed.count(Var)) 1364 continue; 1365 1366 // History contains relevant DBG_VALUE instructions for Var and instructions 1367 // clobbering it. 1368 SmallVectorImpl<const MachineInstr*> &History = DbgValues[Var]; 1369 if (History.empty()) 1370 continue; 1371 const MachineInstr *MInsn = History.front(); 1372 1373 DIVariable DV(Var); 1374 LexicalScope *Scope = NULL; 1375 if (DV.getTag() == dwarf::DW_TAG_arg_variable && 1376 DISubprogram(DV.getContext()).describes(MF->getFunction())) 1377 Scope = LScopes.getCurrentFunctionScope(); 1378 else if (MDNode *IA = DV.getInlinedAt()) 1379 Scope = LScopes.findInlinedScope(DebugLoc::getFromDILocation(IA)); 1380 else 1381 Scope = LScopes.findLexicalScope(cast<MDNode>(DV->getOperand(1))); 1382 // If variable scope is not found then skip this variable. 1383 if (!Scope) 1384 continue; 1385 1386 Processed.insert(DV); 1387 assert(MInsn->isDebugValue() && "History must begin with debug value"); 1388 DbgVariable *AbsVar = findAbstractVariable(DV, MInsn->getDebugLoc()); 1389 DbgVariable *RegVar = new DbgVariable(DV, AbsVar, this); 1390 if (!addCurrentFnArgument(MF, RegVar, Scope)) 1391 addScopeVariable(Scope, RegVar); 1392 if (AbsVar) 1393 AbsVar->setMInsn(MInsn); 1394 1395 // Simplify ranges that are fully coalesced. 1396 if (History.size() <= 1 || (History.size() == 2 && 1397 MInsn->isIdenticalTo(History.back()))) { 1398 RegVar->setMInsn(MInsn); 1399 continue; 1400 } 1401 1402 // Handle multiple DBG_VALUE instructions describing one variable. 1403 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size()); 1404 1405 for (SmallVectorImpl<const MachineInstr*>::const_iterator 1406 HI = History.begin(), HE = History.end(); HI != HE; ++HI) { 1407 const MachineInstr *Begin = *HI; 1408 assert(Begin->isDebugValue() && "Invalid History entry"); 1409 1410 // Check if DBG_VALUE is truncating a range. 1411 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() 1412 && !Begin->getOperand(0).getReg()) 1413 continue; 1414 1415 // Compute the range for a register location. 1416 const MCSymbol *FLabel = getLabelBeforeInsn(Begin); 1417 const MCSymbol *SLabel = 0; 1418 1419 if (HI + 1 == HE) 1420 // If Begin is the last instruction in History then its value is valid 1421 // until the end of the function. 1422 SLabel = FunctionEndSym; 1423 else { 1424 const MachineInstr *End = HI[1]; 1425 DEBUG(dbgs() << "DotDebugLoc Pair:\n" 1426 << "\t" << *Begin << "\t" << *End << "\n"); 1427 if (End->isDebugValue()) 1428 SLabel = getLabelBeforeInsn(End); 1429 else { 1430 // End is a normal instruction clobbering the range. 1431 SLabel = getLabelAfterInsn(End); 1432 assert(SLabel && "Forgot label after clobber instruction"); 1433 ++HI; 1434 } 1435 } 1436 1437 // The value is valid until the next DBG_VALUE or clobber. 1438 DotDebugLocEntries.push_back(getDebugLocEntry(Asm, FLabel, SLabel, 1439 Begin)); 1440 } 1441 DotDebugLocEntries.push_back(DotDebugLocEntry()); 1442 } 1443 1444 // Collect info for variables that were optimized out. 1445 LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); 1446 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables(); 1447 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) { 1448 DIVariable DV(Variables.getElement(i)); 1449 if (!DV || !DV.isVariable() || !Processed.insert(DV)) 1450 continue; 1451 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext())) 1452 addScopeVariable(Scope, new DbgVariable(DV, NULL, this)); 1453 } 1454} 1455 1456// Return Label preceding the instruction. 1457MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) { 1458 MCSymbol *Label = LabelsBeforeInsn.lookup(MI); 1459 assert(Label && "Didn't insert label before instruction"); 1460 return Label; 1461} 1462 1463// Return Label immediately following the instruction. 1464MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) { 1465 return LabelsAfterInsn.lookup(MI); 1466} 1467 1468// Process beginning of an instruction. 1469void DwarfDebug::beginInstruction(const MachineInstr *MI) { 1470 // Check if source location changes, but ignore DBG_VALUE locations. 1471 if (!MI->isDebugValue()) { 1472 DebugLoc DL = MI->getDebugLoc(); 1473 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) { 1474 unsigned Flags = 0; 1475 PrevInstLoc = DL; 1476 if (DL == PrologEndLoc) { 1477 Flags |= DWARF2_FLAG_PROLOGUE_END; 1478 PrologEndLoc = DebugLoc(); 1479 } 1480 if (PrologEndLoc.isUnknown()) 1481 Flags |= DWARF2_FLAG_IS_STMT; 1482 1483 if (!DL.isUnknown()) { 1484 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext()); 1485 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags); 1486 } else 1487 recordSourceLine(0, 0, 0, 0); 1488 } 1489 } 1490 1491 // Insert labels where requested. 1492 DenseMap<const MachineInstr*, MCSymbol*>::iterator I = 1493 LabelsBeforeInsn.find(MI); 1494 1495 // No label needed. 1496 if (I == LabelsBeforeInsn.end()) 1497 return; 1498 1499 // Label already assigned. 1500 if (I->second) 1501 return; 1502 1503 if (!PrevLabel) { 1504 PrevLabel = MMI->getContext().CreateTempSymbol(); 1505 Asm->OutStreamer.EmitLabel(PrevLabel); 1506 } 1507 I->second = PrevLabel; 1508} 1509 1510// Process end of an instruction. 1511void DwarfDebug::endInstruction(const MachineInstr *MI) { 1512 // Don't create a new label after DBG_VALUE instructions. 1513 // They don't generate code. 1514 if (!MI->isDebugValue()) 1515 PrevLabel = 0; 1516 1517 DenseMap<const MachineInstr*, MCSymbol*>::iterator I = 1518 LabelsAfterInsn.find(MI); 1519 1520 // No label needed. 1521 if (I == LabelsAfterInsn.end()) 1522 return; 1523 1524 // Label already assigned. 1525 if (I->second) 1526 return; 1527 1528 // We need a label after this instruction. 1529 if (!PrevLabel) { 1530 PrevLabel = MMI->getContext().CreateTempSymbol(); 1531 Asm->OutStreamer.EmitLabel(PrevLabel); 1532 } 1533 I->second = PrevLabel; 1534} 1535 1536// Each LexicalScope has first instruction and last instruction to mark 1537// beginning and end of a scope respectively. Create an inverse map that list 1538// scopes starts (and ends) with an instruction. One instruction may start (or 1539// end) multiple scopes. Ignore scopes that are not reachable. 1540void DwarfDebug::identifyScopeMarkers() { 1541 SmallVector<LexicalScope *, 4> WorkList; 1542 WorkList.push_back(LScopes.getCurrentFunctionScope()); 1543 while (!WorkList.empty()) { 1544 LexicalScope *S = WorkList.pop_back_val(); 1545 1546 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren(); 1547 if (!Children.empty()) 1548 for (SmallVectorImpl<LexicalScope *>::const_iterator SI = Children.begin(), 1549 SE = Children.end(); SI != SE; ++SI) 1550 WorkList.push_back(*SI); 1551 1552 if (S->isAbstractScope()) 1553 continue; 1554 1555 const SmallVectorImpl<InsnRange> &Ranges = S->getRanges(); 1556 if (Ranges.empty()) 1557 continue; 1558 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(), 1559 RE = Ranges.end(); RI != RE; ++RI) { 1560 assert(RI->first && "InsnRange does not have first instruction!"); 1561 assert(RI->second && "InsnRange does not have second instruction!"); 1562 requestLabelBeforeInsn(RI->first); 1563 requestLabelAfterInsn(RI->second); 1564 } 1565 } 1566} 1567 1568// Get MDNode for DebugLoc's scope. 1569static MDNode *getScopeNode(DebugLoc DL, const LLVMContext &Ctx) { 1570 if (MDNode *InlinedAt = DL.getInlinedAt(Ctx)) 1571 return getScopeNode(DebugLoc::getFromDILocation(InlinedAt), Ctx); 1572 return DL.getScope(Ctx); 1573} 1574 1575// Walk up the scope chain of given debug loc and find line number info 1576// for the function. 1577static DebugLoc getFnDebugLoc(DebugLoc DL, const LLVMContext &Ctx) { 1578 const MDNode *Scope = getScopeNode(DL, Ctx); 1579 DISubprogram SP = getDISubprogram(Scope); 1580 if (SP.isSubprogram()) { 1581 // Check for number of operands since the compatibility is 1582 // cheap here. 1583 if (SP->getNumOperands() > 19) 1584 return DebugLoc::get(SP.getScopeLineNumber(), 0, SP); 1585 else 1586 return DebugLoc::get(SP.getLineNumber(), 0, SP); 1587 } 1588 1589 return DebugLoc(); 1590} 1591 1592// Gather pre-function debug information. Assumes being called immediately 1593// after the function entry point has been emitted. 1594void DwarfDebug::beginFunction(const MachineFunction *MF) { 1595 if (!MMI->hasDebugInfo()) return; 1596 LScopes.initialize(*MF); 1597 if (LScopes.empty()) return; 1598 identifyScopeMarkers(); 1599 1600 // Set DwarfCompileUnitID in MCContext to the Compile Unit this function 1601 // belongs to. 1602 LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); 1603 CompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode()); 1604 assert(TheCU && "Unable to find compile unit!"); 1605 if (Asm->TM.hasMCUseLoc() && Asm->OutStreamer.hasRawTextSupport()) 1606 // Use a single line table if we are using .loc and generating assembly. 1607 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0); 1608 else 1609 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID()); 1610 1611 FunctionBeginSym = Asm->GetTempSymbol("func_begin", 1612 Asm->getFunctionNumber()); 1613 // Assumes in correct section after the entry point. 1614 Asm->OutStreamer.EmitLabel(FunctionBeginSym); 1615 1616 assert(UserVariables.empty() && DbgValues.empty() && "Maps weren't cleaned"); 1617 1618 const TargetRegisterInfo *TRI = Asm->TM.getRegisterInfo(); 1619 // LiveUserVar - Map physreg numbers to the MDNode they contain. 1620 std::vector<const MDNode*> LiveUserVar(TRI->getNumRegs()); 1621 1622 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end(); 1623 I != E; ++I) { 1624 bool AtBlockEntry = true; 1625 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end(); 1626 II != IE; ++II) { 1627 const MachineInstr *MI = II; 1628 1629 if (MI->isDebugValue()) { 1630 assert(MI->getNumOperands() > 1 && "Invalid machine instruction!"); 1631 1632 // Keep track of user variables. 1633 const MDNode *Var = 1634 MI->getOperand(MI->getNumOperands() - 1).getMetadata(); 1635 1636 // Variable is in a register, we need to check for clobbers. 1637 if (isDbgValueInDefinedReg(MI)) 1638 LiveUserVar[MI->getOperand(0).getReg()] = Var; 1639 1640 // Check the history of this variable. 1641 SmallVectorImpl<const MachineInstr*> &History = DbgValues[Var]; 1642 if (History.empty()) { 1643 UserVariables.push_back(Var); 1644 // The first mention of a function argument gets the FunctionBeginSym 1645 // label, so arguments are visible when breaking at function entry. 1646 DIVariable DV(Var); 1647 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable && 1648 DISubprogram(getDISubprogram(DV.getContext())) 1649 .describes(MF->getFunction())) 1650 LabelsBeforeInsn[MI] = FunctionBeginSym; 1651 } else { 1652 // We have seen this variable before. Try to coalesce DBG_VALUEs. 1653 const MachineInstr *Prev = History.back(); 1654 if (Prev->isDebugValue()) { 1655 // Coalesce identical entries at the end of History. 1656 if (History.size() >= 2 && 1657 Prev->isIdenticalTo(History[History.size() - 2])) { 1658 DEBUG(dbgs() << "Coalescing identical DBG_VALUE entries:\n" 1659 << "\t" << *Prev 1660 << "\t" << *History[History.size() - 2] << "\n"); 1661 History.pop_back(); 1662 } 1663 1664 // Terminate old register assignments that don't reach MI; 1665 MachineFunction::const_iterator PrevMBB = Prev->getParent(); 1666 if (PrevMBB != I && (!AtBlockEntry || llvm::next(PrevMBB) != I) && 1667 isDbgValueInDefinedReg(Prev)) { 1668 // Previous register assignment needs to terminate at the end of 1669 // its basic block. 1670 MachineBasicBlock::const_iterator LastMI = 1671 PrevMBB->getLastNonDebugInstr(); 1672 if (LastMI == PrevMBB->end()) { 1673 // Drop DBG_VALUE for empty range. 1674 DEBUG(dbgs() << "Dropping DBG_VALUE for empty range:\n" 1675 << "\t" << *Prev << "\n"); 1676 History.pop_back(); 1677 } else if (llvm::next(PrevMBB) != PrevMBB->getParent()->end()) 1678 // Terminate after LastMI. 1679 History.push_back(LastMI); 1680 } 1681 } 1682 } 1683 History.push_back(MI); 1684 } else { 1685 // Not a DBG_VALUE instruction. 1686 if (!MI->isLabel()) 1687 AtBlockEntry = false; 1688 1689 // First known non-DBG_VALUE and non-frame setup location marks 1690 // the beginning of the function body. 1691 if (!MI->getFlag(MachineInstr::FrameSetup) && 1692 (PrologEndLoc.isUnknown() && !MI->getDebugLoc().isUnknown())) 1693 PrologEndLoc = MI->getDebugLoc(); 1694 1695 // Check if the instruction clobbers any registers with debug vars. 1696 for (MachineInstr::const_mop_iterator MOI = MI->operands_begin(), 1697 MOE = MI->operands_end(); MOI != MOE; ++MOI) { 1698 if (!MOI->isReg() || !MOI->isDef() || !MOI->getReg()) 1699 continue; 1700 for (MCRegAliasIterator AI(MOI->getReg(), TRI, true); 1701 AI.isValid(); ++AI) { 1702 unsigned Reg = *AI; 1703 const MDNode *Var = LiveUserVar[Reg]; 1704 if (!Var) 1705 continue; 1706 // Reg is now clobbered. 1707 LiveUserVar[Reg] = 0; 1708 1709 // Was MD last defined by a DBG_VALUE referring to Reg? 1710 DbgValueHistoryMap::iterator HistI = DbgValues.find(Var); 1711 if (HistI == DbgValues.end()) 1712 continue; 1713 SmallVectorImpl<const MachineInstr*> &History = HistI->second; 1714 if (History.empty()) 1715 continue; 1716 const MachineInstr *Prev = History.back(); 1717 // Sanity-check: Register assignments are terminated at the end of 1718 // their block. 1719 if (!Prev->isDebugValue() || Prev->getParent() != MI->getParent()) 1720 continue; 1721 // Is the variable still in Reg? 1722 if (!isDbgValueInDefinedReg(Prev) || 1723 Prev->getOperand(0).getReg() != Reg) 1724 continue; 1725 // Var is clobbered. Make sure the next instruction gets a label. 1726 History.push_back(MI); 1727 } 1728 } 1729 } 1730 } 1731 } 1732 1733 for (DbgValueHistoryMap::iterator I = DbgValues.begin(), E = DbgValues.end(); 1734 I != E; ++I) { 1735 SmallVectorImpl<const MachineInstr*> &History = I->second; 1736 if (History.empty()) 1737 continue; 1738 1739 // Make sure the final register assignments are terminated. 1740 const MachineInstr *Prev = History.back(); 1741 if (Prev->isDebugValue() && isDbgValueInDefinedReg(Prev)) { 1742 const MachineBasicBlock *PrevMBB = Prev->getParent(); 1743 MachineBasicBlock::const_iterator LastMI = 1744 PrevMBB->getLastNonDebugInstr(); 1745 if (LastMI == PrevMBB->end()) 1746 // Drop DBG_VALUE for empty range. 1747 History.pop_back(); 1748 else if (PrevMBB != &PrevMBB->getParent()->back()) { 1749 // Terminate after LastMI. 1750 History.push_back(LastMI); 1751 } 1752 } 1753 // Request labels for the full history. 1754 for (unsigned i = 0, e = History.size(); i != e; ++i) { 1755 const MachineInstr *MI = History[i]; 1756 if (MI->isDebugValue()) 1757 requestLabelBeforeInsn(MI); 1758 else 1759 requestLabelAfterInsn(MI); 1760 } 1761 } 1762 1763 PrevInstLoc = DebugLoc(); 1764 PrevLabel = FunctionBeginSym; 1765 1766 // Record beginning of function. 1767 if (!PrologEndLoc.isUnknown()) { 1768 DebugLoc FnStartDL = getFnDebugLoc(PrologEndLoc, 1769 MF->getFunction()->getContext()); 1770 recordSourceLine(FnStartDL.getLine(), FnStartDL.getCol(), 1771 FnStartDL.getScope(MF->getFunction()->getContext()), 1772 // We'd like to list the prologue as "not statements" but GDB behaves 1773 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing. 1774 DWARF2_FLAG_IS_STMT); 1775 } 1776} 1777 1778void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) { 1779 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS]; 1780 DIVariable DV = Var->getVariable(); 1781 // Variables with positive arg numbers are parameters. 1782 if (unsigned ArgNum = DV.getArgNumber()) { 1783 // Keep all parameters in order at the start of the variable list to ensure 1784 // function types are correct (no out-of-order parameters) 1785 // 1786 // This could be improved by only doing it for optimized builds (unoptimized 1787 // builds have the right order to begin with), searching from the back (this 1788 // would catch the unoptimized case quickly), or doing a binary search 1789 // rather than linear search. 1790 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin(); 1791 while (I != Vars.end()) { 1792 unsigned CurNum = (*I)->getVariable().getArgNumber(); 1793 // A local (non-parameter) variable has been found, insert immediately 1794 // before it. 1795 if (CurNum == 0) 1796 break; 1797 // A later indexed parameter has been found, insert immediately before it. 1798 if (CurNum > ArgNum) 1799 break; 1800 ++I; 1801 } 1802 Vars.insert(I, Var); 1803 return; 1804 } 1805 1806 Vars.push_back(Var); 1807} 1808 1809// Gather and emit post-function debug information. 1810void DwarfDebug::endFunction(const MachineFunction *MF) { 1811 if (!MMI->hasDebugInfo() || LScopes.empty()) return; 1812 1813 // Define end label for subprogram. 1814 FunctionEndSym = Asm->GetTempSymbol("func_end", 1815 Asm->getFunctionNumber()); 1816 // Assumes in correct section after the entry point. 1817 Asm->OutStreamer.EmitLabel(FunctionEndSym); 1818 // Set DwarfCompileUnitID in MCContext to default value. 1819 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0); 1820 1821 SmallPtrSet<const MDNode *, 16> ProcessedVars; 1822 collectVariableInfo(MF, ProcessedVars); 1823 1824 LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); 1825 CompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode()); 1826 assert(TheCU && "Unable to find compile unit!"); 1827 1828 // Construct abstract scopes. 1829 ArrayRef<LexicalScope *> AList = LScopes.getAbstractScopesList(); 1830 for (unsigned i = 0, e = AList.size(); i != e; ++i) { 1831 LexicalScope *AScope = AList[i]; 1832 DISubprogram SP(AScope->getScopeNode()); 1833 if (SP.isSubprogram()) { 1834 // Collect info for variables that were optimized out. 1835 DIArray Variables = SP.getVariables(); 1836 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) { 1837 DIVariable DV(Variables.getElement(i)); 1838 if (!DV || !DV.isVariable() || !ProcessedVars.insert(DV)) 1839 continue; 1840 // Check that DbgVariable for DV wasn't created earlier, when 1841 // findAbstractVariable() was called for inlined instance of DV. 1842 LLVMContext &Ctx = DV->getContext(); 1843 DIVariable CleanDV = cleanseInlinedVariable(DV, Ctx); 1844 if (AbstractVariables.lookup(CleanDV)) 1845 continue; 1846 if (LexicalScope *Scope = LScopes.findAbstractScope(DV.getContext())) 1847 addScopeVariable(Scope, new DbgVariable(DV, NULL, this)); 1848 } 1849 } 1850 if (ProcessedSPNodes.count(AScope->getScopeNode()) == 0) 1851 constructScopeDIE(TheCU, AScope); 1852 } 1853 1854 DIE *CurFnDIE = constructScopeDIE(TheCU, FnScope); 1855 1856 if (!MF->getTarget().Options.DisableFramePointerElim(*MF)) 1857 TheCU->addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr); 1858 1859 // Clear debug info 1860 for (ScopeVariablesMap::iterator 1861 I = ScopeVariables.begin(), E = ScopeVariables.end(); I != E; ++I) 1862 DeleteContainerPointers(I->second); 1863 ScopeVariables.clear(); 1864 DeleteContainerPointers(CurrentFnArguments); 1865 UserVariables.clear(); 1866 DbgValues.clear(); 1867 AbstractVariables.clear(); 1868 LabelsBeforeInsn.clear(); 1869 LabelsAfterInsn.clear(); 1870 PrevLabel = NULL; 1871} 1872 1873// Register a source line with debug info. Returns the unique label that was 1874// emitted and which provides correspondence to the source line list. 1875void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S, 1876 unsigned Flags) { 1877 StringRef Fn; 1878 StringRef Dir; 1879 unsigned Src = 1; 1880 if (S) { 1881 DIDescriptor Scope(S); 1882 1883 if (Scope.isCompileUnit()) { 1884 DICompileUnit CU(S); 1885 Fn = CU.getFilename(); 1886 Dir = CU.getDirectory(); 1887 } else if (Scope.isFile()) { 1888 DIFile F(S); 1889 Fn = F.getFilename(); 1890 Dir = F.getDirectory(); 1891 } else if (Scope.isSubprogram()) { 1892 DISubprogram SP(S); 1893 Fn = SP.getFilename(); 1894 Dir = SP.getDirectory(); 1895 } else if (Scope.isLexicalBlockFile()) { 1896 DILexicalBlockFile DBF(S); 1897 Fn = DBF.getFilename(); 1898 Dir = DBF.getDirectory(); 1899 } else if (Scope.isLexicalBlock()) { 1900 DILexicalBlock DB(S); 1901 Fn = DB.getFilename(); 1902 Dir = DB.getDirectory(); 1903 } else 1904 llvm_unreachable("Unexpected scope info"); 1905 1906 Src = getOrCreateSourceID(Fn, Dir, 1907 Asm->OutStreamer.getContext().getDwarfCompileUnitID()); 1908 } 1909 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0, 0, Fn); 1910} 1911 1912//===----------------------------------------------------------------------===// 1913// Emit Methods 1914//===----------------------------------------------------------------------===// 1915 1916// Compute the size and offset of a DIE. 1917unsigned 1918DwarfUnits::computeSizeAndOffset(DIE *Die, unsigned Offset) { 1919 // Get the children. 1920 const std::vector<DIE *> &Children = Die->getChildren(); 1921 1922 // Record the abbreviation. 1923 assignAbbrevNumber(Die->getAbbrev()); 1924 1925 // Get the abbreviation for this DIE. 1926 unsigned AbbrevNumber = Die->getAbbrevNumber(); 1927 const DIEAbbrev *Abbrev = Abbreviations->at(AbbrevNumber - 1); 1928 1929 // Set DIE offset 1930 Die->setOffset(Offset); 1931 1932 // Start the size with the size of abbreviation code. 1933 Offset += MCAsmInfo::getULEB128Size(AbbrevNumber); 1934 1935 const SmallVectorImpl<DIEValue*> &Values = Die->getValues(); 1936 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev->getData(); 1937 1938 // Size the DIE attribute values. 1939 for (unsigned i = 0, N = Values.size(); i < N; ++i) 1940 // Size attribute value. 1941 Offset += Values[i]->SizeOf(Asm, AbbrevData[i].getForm()); 1942 1943 // Size the DIE children if any. 1944 if (!Children.empty()) { 1945 assert(Abbrev->getChildrenFlag() == dwarf::DW_CHILDREN_yes && 1946 "Children flag not set"); 1947 1948 for (unsigned j = 0, M = Children.size(); j < M; ++j) 1949 Offset = computeSizeAndOffset(Children[j], Offset); 1950 1951 // End of children marker. 1952 Offset += sizeof(int8_t); 1953 } 1954 1955 Die->setSize(Offset - Die->getOffset()); 1956 return Offset; 1957} 1958 1959// Compute the size and offset of all the DIEs. 1960void DwarfUnits::computeSizeAndOffsets() { 1961 // Offset from the beginning of debug info section. 1962 for (SmallVectorImpl<CompileUnit *>::iterator I = CUs.begin(), 1963 E = CUs.end(); I != E; ++I) { 1964 unsigned Offset = 1965 sizeof(int32_t) + // Length of Compilation Unit Info 1966 sizeof(int16_t) + // DWARF version number 1967 sizeof(int32_t) + // Offset Into Abbrev. Section 1968 sizeof(int8_t); // Pointer Size (in bytes) 1969 computeSizeAndOffset((*I)->getCUDie(), Offset); 1970 } 1971} 1972 1973// Emit initial Dwarf sections with a label at the start of each one. 1974void DwarfDebug::emitSectionLabels() { 1975 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); 1976 1977 // Dwarf sections base addresses. 1978 DwarfInfoSectionSym = 1979 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info"); 1980 DwarfAbbrevSectionSym = 1981 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev"); 1982 if (useSplitDwarf()) 1983 DwarfAbbrevDWOSectionSym = 1984 emitSectionSym(Asm, TLOF.getDwarfAbbrevDWOSection(), 1985 "section_abbrev_dwo"); 1986 emitSectionSym(Asm, TLOF.getDwarfARangesSection()); 1987 1988 if (const MCSection *MacroInfo = TLOF.getDwarfMacroInfoSection()) 1989 emitSectionSym(Asm, MacroInfo); 1990 1991 DwarfLineSectionSym = 1992 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line"); 1993 emitSectionSym(Asm, TLOF.getDwarfLocSection()); 1994 if (GenerateGnuPubSections) { 1995 DwarfGnuPubNamesSectionSym = 1996 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection()); 1997 DwarfGnuPubTypesSectionSym = 1998 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection()); 1999 } else if (HasDwarfPubSections) { 2000 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection()); 2001 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection()); 2002 } 2003 2004 DwarfStrSectionSym = 2005 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string"); 2006 if (useSplitDwarf()) { 2007 DwarfStrDWOSectionSym = 2008 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string"); 2009 DwarfAddrSectionSym = 2010 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec"); 2011 } 2012 DwarfDebugRangeSectionSym = emitSectionSym(Asm, TLOF.getDwarfRangesSection(), 2013 "debug_range"); 2014 2015 DwarfDebugLocSectionSym = emitSectionSym(Asm, TLOF.getDwarfLocSection(), 2016 "section_debug_loc"); 2017 2018 TextSectionSym = emitSectionSym(Asm, TLOF.getTextSection(), "text_begin"); 2019 emitSectionSym(Asm, TLOF.getDataSection()); 2020} 2021 2022// Recursively emits a debug information entry. 2023void DwarfDebug::emitDIE(DIE *Die, std::vector<DIEAbbrev *> *Abbrevs) { 2024 // Get the abbreviation for this DIE. 2025 unsigned AbbrevNumber = Die->getAbbrevNumber(); 2026 const DIEAbbrev *Abbrev = Abbrevs->at(AbbrevNumber - 1); 2027 2028 // Emit the code (index) for the abbreviation. 2029 if (Asm->isVerbose()) 2030 Asm->OutStreamer.AddComment("Abbrev [" + Twine(AbbrevNumber) + "] 0x" + 2031 Twine::utohexstr(Die->getOffset()) + ":0x" + 2032 Twine::utohexstr(Die->getSize()) + " " + 2033 dwarf::TagString(Abbrev->getTag())); 2034 Asm->EmitULEB128(AbbrevNumber); 2035 2036 const SmallVectorImpl<DIEValue*> &Values = Die->getValues(); 2037 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev->getData(); 2038 2039 // Emit the DIE attribute values. 2040 for (unsigned i = 0, N = Values.size(); i < N; ++i) { 2041 unsigned Attr = AbbrevData[i].getAttribute(); 2042 unsigned Form = AbbrevData[i].getForm(); 2043 assert(Form && "Too many attributes for DIE (check abbreviation)"); 2044 2045 if (Asm->isVerbose()) 2046 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr)); 2047 2048 switch (Attr) { 2049 case dwarf::DW_AT_abstract_origin: { 2050 DIEEntry *E = cast<DIEEntry>(Values[i]); 2051 DIE *Origin = E->getEntry(); 2052 unsigned Addr = Origin->getOffset(); 2053 Asm->EmitInt32(Addr); 2054 break; 2055 } 2056 case dwarf::DW_AT_ranges: { 2057 // DW_AT_range Value encodes offset in debug_range section. 2058 DIEInteger *V = cast<DIEInteger>(Values[i]); 2059 2060 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) { 2061 Asm->EmitLabelPlusOffset(DwarfDebugRangeSectionSym, 2062 V->getValue(), 2063 4); 2064 } else { 2065 Asm->EmitLabelOffsetDifference(DwarfDebugRangeSectionSym, 2066 V->getValue(), 2067 DwarfDebugRangeSectionSym, 2068 4); 2069 } 2070 break; 2071 } 2072 case dwarf::DW_AT_location: { 2073 if (DIELabel *L = dyn_cast<DIELabel>(Values[i])) { 2074 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2075 Asm->EmitLabelReference(L->getValue(), 4); 2076 else 2077 Asm->EmitLabelDifference(L->getValue(), DwarfDebugLocSectionSym, 4); 2078 } else { 2079 Values[i]->EmitValue(Asm, Form); 2080 } 2081 break; 2082 } 2083 case dwarf::DW_AT_accessibility: { 2084 if (Asm->isVerbose()) { 2085 DIEInteger *V = cast<DIEInteger>(Values[i]); 2086 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(V->getValue())); 2087 } 2088 Values[i]->EmitValue(Asm, Form); 2089 break; 2090 } 2091 default: 2092 // Emit an attribute using the defined form. 2093 Values[i]->EmitValue(Asm, Form); 2094 break; 2095 } 2096 } 2097 2098 // Emit the DIE children if any. 2099 if (Abbrev->getChildrenFlag() == dwarf::DW_CHILDREN_yes) { 2100 const std::vector<DIE *> &Children = Die->getChildren(); 2101 2102 for (unsigned j = 0, M = Children.size(); j < M; ++j) 2103 emitDIE(Children[j], Abbrevs); 2104 2105 if (Asm->isVerbose()) 2106 Asm->OutStreamer.AddComment("End Of Children Mark"); 2107 Asm->EmitInt8(0); 2108 } 2109} 2110 2111// Emit the various dwarf units to the unit section USection with 2112// the abbreviations going into ASection. 2113void DwarfUnits::emitUnits(DwarfDebug *DD, 2114 const MCSection *USection, 2115 const MCSection *ASection, 2116 const MCSymbol *ASectionSym) { 2117 Asm->OutStreamer.SwitchSection(USection); 2118 for (SmallVectorImpl<CompileUnit *>::iterator I = CUs.begin(), 2119 E = CUs.end(); I != E; ++I) { 2120 CompileUnit *TheCU = *I; 2121 DIE *Die = TheCU->getCUDie(); 2122 2123 // Emit the compile units header. 2124 Asm->OutStreamer 2125 .EmitLabel(Asm->GetTempSymbol(USection->getLabelBeginName(), 2126 TheCU->getUniqueID())); 2127 2128 // Emit size of content not including length itself 2129 unsigned ContentSize = Die->getSize() + 2130 sizeof(int16_t) + // DWARF version number 2131 sizeof(int32_t) + // Offset Into Abbrev. Section 2132 sizeof(int8_t); // Pointer Size (in bytes) 2133 2134 Asm->OutStreamer.AddComment("Length of Compilation Unit Info"); 2135 Asm->EmitInt32(ContentSize); 2136 Asm->OutStreamer.AddComment("DWARF version number"); 2137 Asm->EmitInt16(DD->getDwarfVersion()); 2138 Asm->OutStreamer.AddComment("Offset Into Abbrev. Section"); 2139 Asm->EmitSectionOffset(Asm->GetTempSymbol(ASection->getLabelBeginName()), 2140 ASectionSym); 2141 Asm->OutStreamer.AddComment("Address Size (in bytes)"); 2142 Asm->EmitInt8(Asm->getDataLayout().getPointerSize()); 2143 2144 DD->emitDIE(Die, Abbreviations); 2145 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol(USection->getLabelEndName(), 2146 TheCU->getUniqueID())); 2147 } 2148} 2149 2150// Emit the debug info section. 2151void DwarfDebug::emitDebugInfo() { 2152 DwarfUnits &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; 2153 2154 Holder.emitUnits(this, Asm->getObjFileLowering().getDwarfInfoSection(), 2155 Asm->getObjFileLowering().getDwarfAbbrevSection(), 2156 DwarfAbbrevSectionSym); 2157} 2158 2159// Emit the abbreviation section. 2160void DwarfDebug::emitAbbreviations() { 2161 if (!useSplitDwarf()) 2162 emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection(), 2163 &Abbreviations); 2164 else 2165 emitSkeletonAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection()); 2166} 2167 2168void DwarfDebug::emitAbbrevs(const MCSection *Section, 2169 std::vector<DIEAbbrev *> *Abbrevs) { 2170 // Check to see if it is worth the effort. 2171 if (!Abbrevs->empty()) { 2172 // Start the debug abbrev section. 2173 Asm->OutStreamer.SwitchSection(Section); 2174 2175 MCSymbol *Begin = Asm->GetTempSymbol(Section->getLabelBeginName()); 2176 Asm->OutStreamer.EmitLabel(Begin); 2177 2178 // For each abbrevation. 2179 for (unsigned i = 0, N = Abbrevs->size(); i < N; ++i) { 2180 // Get abbreviation data 2181 const DIEAbbrev *Abbrev = Abbrevs->at(i); 2182 2183 // Emit the abbrevations code (base 1 index.) 2184 Asm->EmitULEB128(Abbrev->getNumber(), "Abbreviation Code"); 2185 2186 // Emit the abbreviations data. 2187 Abbrev->Emit(Asm); 2188 } 2189 2190 // Mark end of abbreviations. 2191 Asm->EmitULEB128(0, "EOM(3)"); 2192 2193 MCSymbol *End = Asm->GetTempSymbol(Section->getLabelEndName()); 2194 Asm->OutStreamer.EmitLabel(End); 2195 } 2196} 2197 2198// Emit the last address of the section and the end of the line matrix. 2199void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) { 2200 // Define last address of section. 2201 Asm->OutStreamer.AddComment("Extended Op"); 2202 Asm->EmitInt8(0); 2203 2204 Asm->OutStreamer.AddComment("Op size"); 2205 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1); 2206 Asm->OutStreamer.AddComment("DW_LNE_set_address"); 2207 Asm->EmitInt8(dwarf::DW_LNE_set_address); 2208 2209 Asm->OutStreamer.AddComment("Section end label"); 2210 2211 Asm->OutStreamer.EmitSymbolValue(Asm->GetTempSymbol("section_end",SectionEnd), 2212 Asm->getDataLayout().getPointerSize()); 2213 2214 // Mark end of matrix. 2215 Asm->OutStreamer.AddComment("DW_LNE_end_sequence"); 2216 Asm->EmitInt8(0); 2217 Asm->EmitInt8(1); 2218 Asm->EmitInt8(1); 2219} 2220 2221// Emit visible names into a hashed accelerator table section. 2222void DwarfDebug::emitAccelNames() { 2223 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2224 dwarf::DW_FORM_data4)); 2225 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2226 E = CUMap.end(); I != E; ++I) { 2227 CompileUnit *TheCU = I->second; 2228 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelNames(); 2229 for (StringMap<std::vector<DIE*> >::const_iterator 2230 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2231 StringRef Name = GI->getKey(); 2232 const std::vector<DIE *> &Entities = GI->second; 2233 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2234 DE = Entities.end(); DI != DE; ++DI) 2235 AT.AddName(Name, (*DI)); 2236 } 2237 } 2238 2239 AT.FinalizeTable(Asm, "Names"); 2240 Asm->OutStreamer.SwitchSection( 2241 Asm->getObjFileLowering().getDwarfAccelNamesSection()); 2242 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin"); 2243 Asm->OutStreamer.EmitLabel(SectionBegin); 2244 2245 // Emit the full data. 2246 AT.Emit(Asm, SectionBegin, &InfoHolder); 2247} 2248 2249// Emit objective C classes and categories into a hashed accelerator table 2250// section. 2251void DwarfDebug::emitAccelObjC() { 2252 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2253 dwarf::DW_FORM_data4)); 2254 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2255 E = CUMap.end(); I != E; ++I) { 2256 CompileUnit *TheCU = I->second; 2257 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelObjC(); 2258 for (StringMap<std::vector<DIE*> >::const_iterator 2259 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2260 StringRef Name = GI->getKey(); 2261 const std::vector<DIE *> &Entities = GI->second; 2262 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2263 DE = Entities.end(); DI != DE; ++DI) 2264 AT.AddName(Name, (*DI)); 2265 } 2266 } 2267 2268 AT.FinalizeTable(Asm, "ObjC"); 2269 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2270 .getDwarfAccelObjCSection()); 2271 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin"); 2272 Asm->OutStreamer.EmitLabel(SectionBegin); 2273 2274 // Emit the full data. 2275 AT.Emit(Asm, SectionBegin, &InfoHolder); 2276} 2277 2278// Emit namespace dies into a hashed accelerator table. 2279void DwarfDebug::emitAccelNamespaces() { 2280 DwarfAccelTable AT(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2281 dwarf::DW_FORM_data4)); 2282 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2283 E = CUMap.end(); I != E; ++I) { 2284 CompileUnit *TheCU = I->second; 2285 const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelNamespace(); 2286 for (StringMap<std::vector<DIE*> >::const_iterator 2287 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2288 StringRef Name = GI->getKey(); 2289 const std::vector<DIE *> &Entities = GI->second; 2290 for (std::vector<DIE *>::const_iterator DI = Entities.begin(), 2291 DE = Entities.end(); DI != DE; ++DI) 2292 AT.AddName(Name, (*DI)); 2293 } 2294 } 2295 2296 AT.FinalizeTable(Asm, "namespac"); 2297 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2298 .getDwarfAccelNamespaceSection()); 2299 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin"); 2300 Asm->OutStreamer.EmitLabel(SectionBegin); 2301 2302 // Emit the full data. 2303 AT.Emit(Asm, SectionBegin, &InfoHolder); 2304} 2305 2306// Emit type dies into a hashed accelerator table. 2307void DwarfDebug::emitAccelTypes() { 2308 std::vector<DwarfAccelTable::Atom> Atoms; 2309 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, 2310 dwarf::DW_FORM_data4)); 2311 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, 2312 dwarf::DW_FORM_data2)); 2313 Atoms.push_back(DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, 2314 dwarf::DW_FORM_data1)); 2315 DwarfAccelTable AT(Atoms); 2316 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2317 E = CUMap.end(); I != E; ++I) { 2318 CompileUnit *TheCU = I->second; 2319 const StringMap<std::vector<std::pair<DIE*, unsigned > > > &Names 2320 = TheCU->getAccelTypes(); 2321 for (StringMap<std::vector<std::pair<DIE*, unsigned> > >::const_iterator 2322 GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) { 2323 StringRef Name = GI->getKey(); 2324 const std::vector<std::pair<DIE *, unsigned> > &Entities = GI->second; 2325 for (std::vector<std::pair<DIE *, unsigned> >::const_iterator DI 2326 = Entities.begin(), DE = Entities.end(); DI !=DE; ++DI) 2327 AT.AddName(Name, (*DI).first, (*DI).second); 2328 } 2329 } 2330 2331 AT.FinalizeTable(Asm, "types"); 2332 Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering() 2333 .getDwarfAccelTypesSection()); 2334 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin"); 2335 Asm->OutStreamer.EmitLabel(SectionBegin); 2336 2337 // Emit the full data. 2338 AT.Emit(Asm, SectionBegin, &InfoHolder); 2339} 2340 2341// Public name handling. 2342// The format for the various pubnames: 2343// 2344// dwarf pubnames - offset/name pairs where the offset is the offset into the CU 2345// for the DIE that is named. 2346// 2347// gnu pubnames - offset/index value/name tuples where the offset is the offset 2348// into the CU and the index value is computed according to the type of value 2349// for the DIE that is named. 2350// 2351// For type units the offset is the offset of the skeleton DIE. For split dwarf 2352// it's the offset within the debug_info/debug_types dwo section, however, the 2353// reference in the pubname header doesn't change. 2354 2355/// computeIndexValue - Compute the gdb index value for the DIE and CU. 2356static dwarf::PubIndexEntryDescriptor computeIndexValue(CompileUnit *CU, 2357 DIE *Die) { 2358 dwarf::GDBIndexEntryLinkage Linkage = 2359 Die->findAttribute(dwarf::DW_AT_external) ? dwarf::GIEL_EXTERNAL 2360 : dwarf::GIEL_STATIC; 2361 2362 switch (Die->getTag()) { 2363 case dwarf::DW_TAG_class_type: 2364 case dwarf::DW_TAG_structure_type: 2365 case dwarf::DW_TAG_union_type: 2366 case dwarf::DW_TAG_enumeration_type: 2367 return dwarf::PubIndexEntryDescriptor( 2368 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus 2369 ? dwarf::GIEL_STATIC 2370 : dwarf::GIEL_EXTERNAL); 2371 case dwarf::DW_TAG_typedef: 2372 case dwarf::DW_TAG_base_type: 2373 case dwarf::DW_TAG_subrange_type: 2374 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC); 2375 case dwarf::DW_TAG_namespace: 2376 return dwarf::GIEK_TYPE; 2377 case dwarf::DW_TAG_subprogram: 2378 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage); 2379 case dwarf::DW_TAG_constant: 2380 case dwarf::DW_TAG_variable: 2381 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage); 2382 case dwarf::DW_TAG_enumerator: 2383 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, 2384 dwarf::GIEL_STATIC); 2385 default: 2386 return dwarf::GIEK_NONE; 2387 } 2388} 2389 2390/// emitDebugPubNames - Emit visible names into a debug pubnames section. 2391/// 2392void DwarfDebug::emitDebugPubNames(bool GnuStyle) { 2393 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2394 const MCSection *PSec = 2395 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection() 2396 : Asm->getObjFileLowering().getDwarfPubNamesSection(); 2397 2398 typedef DenseMap<const MDNode*, CompileUnit*> CUMapType; 2399 for (CUMapType::iterator I = CUMap.begin(), E = CUMap.end(); I != E; ++I) { 2400 CompileUnit *TheCU = I->second; 2401 unsigned ID = TheCU->getUniqueID(); 2402 2403 // Start the dwarf pubnames section. 2404 Asm->OutStreamer.SwitchSection(PSec); 2405 2406 // Emit a label so we can reference the beginning of this pubname section. 2407 if (GnuStyle) 2408 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("gnu_pubnames", 2409 TheCU->getUniqueID())); 2410 2411 // Emit the header. 2412 Asm->OutStreamer.AddComment("Length of Public Names Info"); 2413 Asm->EmitLabelDifference(Asm->GetTempSymbol("pubnames_end", ID), 2414 Asm->GetTempSymbol("pubnames_begin", ID), 4); 2415 2416 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("pubnames_begin", ID)); 2417 2418 Asm->OutStreamer.AddComment("DWARF Version"); 2419 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION); 2420 2421 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info"); 2422 Asm->EmitSectionOffset(Asm->GetTempSymbol(ISec->getLabelBeginName(), ID), 2423 DwarfInfoSectionSym); 2424 2425 Asm->OutStreamer.AddComment("Compilation Unit Length"); 2426 Asm->EmitLabelDifference(Asm->GetTempSymbol(ISec->getLabelEndName(), ID), 2427 Asm->GetTempSymbol(ISec->getLabelBeginName(), ID), 2428 4); 2429 2430 // Emit the pubnames for this compilation unit. 2431 const StringMap<DIE*> &Globals = TheCU->getGlobalNames(); 2432 for (StringMap<DIE*>::const_iterator 2433 GI = Globals.begin(), GE = Globals.end(); GI != GE; ++GI) { 2434 const char *Name = GI->getKeyData(); 2435 DIE *Entity = GI->second; 2436 2437 Asm->OutStreamer.AddComment("DIE offset"); 2438 Asm->EmitInt32(Entity->getOffset()); 2439 2440 if (GnuStyle) { 2441 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheCU, Entity); 2442 Asm->OutStreamer.AddComment( 2443 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " + 2444 dwarf::GDBIndexEntryLinkageString(Desc.Linkage)); 2445 Asm->EmitInt8(Desc.toBits()); 2446 } 2447 2448 if (Asm->isVerbose()) 2449 Asm->OutStreamer.AddComment("External Name"); 2450 Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength()+1)); 2451 } 2452 2453 Asm->OutStreamer.AddComment("End Mark"); 2454 Asm->EmitInt32(0); 2455 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("pubnames_end", ID)); 2456 } 2457} 2458 2459void DwarfDebug::emitDebugPubTypes(bool GnuStyle) { 2460 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2461 const MCSection *PSec = 2462 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection() 2463 : Asm->getObjFileLowering().getDwarfPubTypesSection(); 2464 2465 for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(), 2466 E = CUMap.end(); 2467 I != E; ++I) { 2468 CompileUnit *TheCU = I->second; 2469 // Start the dwarf pubtypes section. 2470 Asm->OutStreamer.SwitchSection(PSec); 2471 2472 // Emit a label so we can reference the beginning of this pubtype section. 2473 if (GnuStyle) 2474 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("gnu_pubtypes", 2475 TheCU->getUniqueID())); 2476 2477 // Emit the header. 2478 Asm->OutStreamer.AddComment("Length of Public Types Info"); 2479 Asm->EmitLabelDifference( 2480 Asm->GetTempSymbol("pubtypes_end", TheCU->getUniqueID()), 2481 Asm->GetTempSymbol("pubtypes_begin", TheCU->getUniqueID()), 4); 2482 2483 Asm->OutStreamer.EmitLabel( 2484 Asm->GetTempSymbol("pubtypes_begin", TheCU->getUniqueID())); 2485 2486 if (Asm->isVerbose()) 2487 Asm->OutStreamer.AddComment("DWARF Version"); 2488 Asm->EmitInt16(dwarf::DW_PUBTYPES_VERSION); 2489 2490 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info"); 2491 Asm->EmitSectionOffset( 2492 Asm->GetTempSymbol(ISec->getLabelBeginName(), TheCU->getUniqueID()), 2493 DwarfInfoSectionSym); 2494 2495 Asm->OutStreamer.AddComment("Compilation Unit Length"); 2496 Asm->EmitLabelDifference( 2497 Asm->GetTempSymbol(ISec->getLabelEndName(), TheCU->getUniqueID()), 2498 Asm->GetTempSymbol(ISec->getLabelBeginName(), TheCU->getUniqueID()), 4); 2499 2500 // Emit the pubtypes. 2501 const StringMap<DIE *> &Globals = TheCU->getGlobalTypes(); 2502 for (StringMap<DIE *>::const_iterator GI = Globals.begin(), 2503 GE = Globals.end(); 2504 GI != GE; ++GI) { 2505 const char *Name = GI->getKeyData(); 2506 DIE *Entity = GI->second; 2507 2508 if (Asm->isVerbose()) 2509 Asm->OutStreamer.AddComment("DIE offset"); 2510 Asm->EmitInt32(Entity->getOffset()); 2511 2512 if (GnuStyle) { 2513 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheCU, Entity); 2514 Asm->OutStreamer.AddComment( 2515 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " + 2516 dwarf::GDBIndexEntryLinkageString(Desc.Linkage)); 2517 Asm->EmitInt8(Desc.toBits()); 2518 } 2519 2520 if (Asm->isVerbose()) 2521 Asm->OutStreamer.AddComment("External Name"); 2522 2523 // Emit the name with a terminating null byte. 2524 Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength() + 1)); 2525 } 2526 2527 Asm->OutStreamer.AddComment("End Mark"); 2528 Asm->EmitInt32(0); 2529 Asm->OutStreamer.EmitLabel( 2530 Asm->GetTempSymbol("pubtypes_end", TheCU->getUniqueID())); 2531 } 2532} 2533 2534// Emit strings into a string section. 2535void DwarfUnits::emitStrings(const MCSection *StrSection, 2536 const MCSection *OffsetSection = NULL, 2537 const MCSymbol *StrSecSym = NULL) { 2538 2539 if (StringPool.empty()) return; 2540 2541 // Start the dwarf str section. 2542 Asm->OutStreamer.SwitchSection(StrSection); 2543 2544 // Get all of the string pool entries and put them in an array by their ID so 2545 // we can sort them. 2546 SmallVector<std::pair<unsigned, 2547 StringMapEntry<std::pair<MCSymbol*, unsigned> >*>, 64> Entries; 2548 2549 for (StringMap<std::pair<MCSymbol*, unsigned> >::iterator 2550 I = StringPool.begin(), E = StringPool.end(); 2551 I != E; ++I) 2552 Entries.push_back(std::make_pair(I->second.second, &*I)); 2553 2554 array_pod_sort(Entries.begin(), Entries.end()); 2555 2556 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2557 // Emit a label for reference from debug information entries. 2558 Asm->OutStreamer.EmitLabel(Entries[i].second->getValue().first); 2559 2560 // Emit the string itself with a terminating null byte. 2561 Asm->OutStreamer.EmitBytes(StringRef(Entries[i].second->getKeyData(), 2562 Entries[i].second->getKeyLength()+1)); 2563 } 2564 2565 // If we've got an offset section go ahead and emit that now as well. 2566 if (OffsetSection) { 2567 Asm->OutStreamer.SwitchSection(OffsetSection); 2568 unsigned offset = 0; 2569 unsigned size = 4; // FIXME: DWARF64 is 8. 2570 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2571 Asm->OutStreamer.EmitIntValue(offset, size); 2572 offset += Entries[i].second->getKeyLength() + 1; 2573 } 2574 } 2575} 2576 2577// Emit strings into a string section. 2578void DwarfUnits::emitAddresses(const MCSection *AddrSection) { 2579 2580 if (AddressPool.empty()) return; 2581 2582 // Start the dwarf addr section. 2583 Asm->OutStreamer.SwitchSection(AddrSection); 2584 2585 // Order the address pool entries by ID 2586 SmallVector<const MCExpr *, 64> Entries(AddressPool.size()); 2587 2588 for (DenseMap<const MCExpr *, unsigned>::iterator I = AddressPool.begin(), 2589 E = AddressPool.end(); 2590 I != E; ++I) 2591 Entries[I->second] = I->first; 2592 2593 for (unsigned i = 0, e = Entries.size(); i != e; ++i) { 2594 // Emit an expression for reference from debug information entries. 2595 if (const MCExpr *Expr = Entries[i]) 2596 Asm->OutStreamer.EmitValue(Expr, Asm->getDataLayout().getPointerSize()); 2597 else 2598 Asm->OutStreamer.EmitIntValue(0, Asm->getDataLayout().getPointerSize()); 2599 } 2600 2601} 2602 2603// Emit visible names into a debug str section. 2604void DwarfDebug::emitDebugStr() { 2605 DwarfUnits &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; 2606 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection()); 2607} 2608 2609// Emit locations into the debug loc section. 2610void DwarfDebug::emitDebugLoc() { 2611 if (DotDebugLocEntries.empty()) 2612 return; 2613 2614 for (SmallVectorImpl<DotDebugLocEntry>::iterator 2615 I = DotDebugLocEntries.begin(), E = DotDebugLocEntries.end(); 2616 I != E; ++I) { 2617 DotDebugLocEntry &Entry = *I; 2618 if (I + 1 != DotDebugLocEntries.end()) 2619 Entry.Merge(I+1); 2620 } 2621 2622 // Start the dwarf loc section. 2623 Asm->OutStreamer.SwitchSection( 2624 Asm->getObjFileLowering().getDwarfLocSection()); 2625 unsigned char Size = Asm->getDataLayout().getPointerSize(); 2626 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", 0)); 2627 unsigned index = 1; 2628 for (SmallVectorImpl<DotDebugLocEntry>::iterator 2629 I = DotDebugLocEntries.begin(), E = DotDebugLocEntries.end(); 2630 I != E; ++I, ++index) { 2631 DotDebugLocEntry &Entry = *I; 2632 if (Entry.isMerged()) continue; 2633 if (Entry.isEmpty()) { 2634 Asm->OutStreamer.EmitIntValue(0, Size); 2635 Asm->OutStreamer.EmitIntValue(0, Size); 2636 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", index)); 2637 } else { 2638 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size); 2639 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size); 2640 DIVariable DV(Entry.getVariable()); 2641 Asm->OutStreamer.AddComment("Loc expr size"); 2642 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol(); 2643 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol(); 2644 Asm->EmitLabelDifference(end, begin, 2); 2645 Asm->OutStreamer.EmitLabel(begin); 2646 if (Entry.isInt()) { 2647 DIBasicType BTy(DV.getType()); 2648 if (BTy.Verify() && 2649 (BTy.getEncoding() == dwarf::DW_ATE_signed 2650 || BTy.getEncoding() == dwarf::DW_ATE_signed_char)) { 2651 Asm->OutStreamer.AddComment("DW_OP_consts"); 2652 Asm->EmitInt8(dwarf::DW_OP_consts); 2653 Asm->EmitSLEB128(Entry.getInt()); 2654 } else { 2655 Asm->OutStreamer.AddComment("DW_OP_constu"); 2656 Asm->EmitInt8(dwarf::DW_OP_constu); 2657 Asm->EmitULEB128(Entry.getInt()); 2658 } 2659 } else if (Entry.isLocation()) { 2660 MachineLocation Loc = Entry.getLoc(); 2661 if (!DV.hasComplexAddress()) 2662 // Regular entry. 2663 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2664 else { 2665 // Complex address entry. 2666 unsigned N = DV.getNumAddrElements(); 2667 unsigned i = 0; 2668 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) { 2669 if (Loc.getOffset()) { 2670 i = 2; 2671 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2672 Asm->OutStreamer.AddComment("DW_OP_deref"); 2673 Asm->EmitInt8(dwarf::DW_OP_deref); 2674 Asm->OutStreamer.AddComment("DW_OP_plus_uconst"); 2675 Asm->EmitInt8(dwarf::DW_OP_plus_uconst); 2676 Asm->EmitSLEB128(DV.getAddrElement(1)); 2677 } else { 2678 // If first address element is OpPlus then emit 2679 // DW_OP_breg + Offset instead of DW_OP_reg + Offset. 2680 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1)); 2681 Asm->EmitDwarfRegOp(TLoc, DV.isIndirect()); 2682 i = 2; 2683 } 2684 } else { 2685 Asm->EmitDwarfRegOp(Loc, DV.isIndirect()); 2686 } 2687 2688 // Emit remaining complex address elements. 2689 for (; i < N; ++i) { 2690 uint64_t Element = DV.getAddrElement(i); 2691 if (Element == DIBuilder::OpPlus) { 2692 Asm->EmitInt8(dwarf::DW_OP_plus_uconst); 2693 Asm->EmitULEB128(DV.getAddrElement(++i)); 2694 } else if (Element == DIBuilder::OpDeref) { 2695 if (!Loc.isReg()) 2696 Asm->EmitInt8(dwarf::DW_OP_deref); 2697 } else 2698 llvm_unreachable("unknown Opcode found in complex address"); 2699 } 2700 } 2701 } 2702 // else ... ignore constant fp. There is not any good way to 2703 // to represent them here in dwarf. 2704 Asm->OutStreamer.EmitLabel(end); 2705 } 2706 } 2707} 2708 2709struct SymbolCUSorter { 2710 SymbolCUSorter(const MCStreamer &s) : Streamer(s) {} 2711 const MCStreamer &Streamer; 2712 2713 bool operator() (const SymbolCU &A, const SymbolCU &B) { 2714 unsigned IA = A.Sym ? Streamer.GetSymbolOrder(A.Sym) : 0; 2715 unsigned IB = B.Sym ? Streamer.GetSymbolOrder(B.Sym) : 0; 2716 2717 // Symbols with no order assigned should be placed at the end. 2718 // (e.g. section end labels) 2719 if (IA == 0) 2720 IA = (unsigned)(-1); 2721 if (IB == 0) 2722 IB = (unsigned)(-1); 2723 return IA < IB; 2724 } 2725}; 2726 2727static bool CUSort(const CompileUnit *A, const CompileUnit *B) { 2728 return (A->getUniqueID() < B->getUniqueID()); 2729} 2730 2731struct ArangeSpan { 2732 const MCSymbol *Start, *End; 2733}; 2734 2735// Emit a debug aranges section, containing a CU lookup for any 2736// address we can tie back to a CU. 2737void DwarfDebug::emitDebugARanges() { 2738 // Start the dwarf aranges section. 2739 Asm->OutStreamer 2740 .SwitchSection(Asm->getObjFileLowering().getDwarfARangesSection()); 2741 2742 typedef DenseMap<CompileUnit *, std::vector<ArangeSpan> > SpansType; 2743 2744 SpansType Spans; 2745 2746 // Build a list of sections used. 2747 std::vector<const MCSection *> Sections; 2748 for (SectionMapType::iterator it = SectionMap.begin(); it != SectionMap.end(); 2749 it++) { 2750 const MCSection *Section = it->first; 2751 Sections.push_back(Section); 2752 } 2753 2754 // Sort the sections into order. 2755 // This is only done to ensure consistent output order across different runs. 2756 std::sort(Sections.begin(), Sections.end(), SectionSort); 2757 2758 // Build a set of address spans, sorted by CU. 2759 for (size_t SecIdx=0;SecIdx<Sections.size();SecIdx++) { 2760 const MCSection *Section = Sections[SecIdx]; 2761 SmallVector<SymbolCU, 8> &List = SectionMap[Section]; 2762 if (List.size() < 2) 2763 continue; 2764 2765 // Sort the symbols by offset within the section. 2766 SymbolCUSorter sorter(Asm->OutStreamer); 2767 std::sort(List.begin(), List.end(), sorter); 2768 2769 // If we have no section (e.g. common), just write out 2770 // individual spans for each symbol. 2771 if (Section == NULL) { 2772 for (size_t n = 0; n < List.size(); n++) { 2773 const SymbolCU &Cur = List[n]; 2774 2775 ArangeSpan Span; 2776 Span.Start = Cur.Sym; 2777 Span.End = NULL; 2778 if (Cur.CU) 2779 Spans[Cur.CU].push_back(Span); 2780 } 2781 } else { 2782 // Build spans between each label. 2783 const MCSymbol *StartSym = List[0].Sym; 2784 for (size_t n = 1; n < List.size(); n++) { 2785 const SymbolCU &Prev = List[n - 1]; 2786 const SymbolCU &Cur = List[n]; 2787 2788 // Try and build the longest span we can within the same CU. 2789 if (Cur.CU != Prev.CU) { 2790 ArangeSpan Span; 2791 Span.Start = StartSym; 2792 Span.End = Cur.Sym; 2793 Spans[Prev.CU].push_back(Span); 2794 StartSym = Cur.Sym; 2795 } 2796 } 2797 } 2798 } 2799 2800 const MCSection *ISec = Asm->getObjFileLowering().getDwarfInfoSection(); 2801 unsigned PtrSize = Asm->getDataLayout().getPointerSize(); 2802 2803 // Build a list of CUs used. 2804 std::vector<CompileUnit *> CUs; 2805 for (SpansType::iterator it = Spans.begin(); it != Spans.end(); it++) { 2806 CompileUnit *CU = it->first; 2807 CUs.push_back(CU); 2808 } 2809 2810 // Sort the CU list (again, to ensure consistent output order). 2811 std::sort(CUs.begin(), CUs.end(), CUSort); 2812 2813 // Emit an arange table for each CU we used. 2814 for (size_t CUIdx=0;CUIdx<CUs.size();CUIdx++) { 2815 CompileUnit *CU = CUs[CUIdx]; 2816 std::vector<ArangeSpan> &List = Spans[CU]; 2817 2818 // Emit size of content not including length itself. 2819 unsigned ContentSize 2820 = sizeof(int16_t) // DWARF ARange version number 2821 + sizeof(int32_t) // Offset of CU in the .debug_info section 2822 + sizeof(int8_t) // Pointer Size (in bytes) 2823 + sizeof(int8_t); // Segment Size (in bytes) 2824 2825 unsigned TupleSize = PtrSize * 2; 2826 2827 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple. 2828 unsigned Padding = 0; 2829 while (((sizeof(int32_t) + ContentSize + Padding) % TupleSize) != 0) 2830 Padding++; 2831 2832 ContentSize += Padding; 2833 ContentSize += (List.size() + 1) * TupleSize; 2834 2835 // For each compile unit, write the list of spans it covers. 2836 Asm->OutStreamer.AddComment("Length of ARange Set"); 2837 Asm->EmitInt32(ContentSize); 2838 Asm->OutStreamer.AddComment("DWARF Arange version number"); 2839 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION); 2840 Asm->OutStreamer.AddComment("Offset Into Debug Info Section"); 2841 Asm->EmitSectionOffset( 2842 Asm->GetTempSymbol(ISec->getLabelBeginName(), CU->getUniqueID()), 2843 DwarfInfoSectionSym); 2844 Asm->OutStreamer.AddComment("Address Size (in bytes)"); 2845 Asm->EmitInt8(PtrSize); 2846 Asm->OutStreamer.AddComment("Segment Size (in bytes)"); 2847 Asm->EmitInt8(0); 2848 2849 for (unsigned n = 0; n < Padding; n++) 2850 Asm->EmitInt8(0xff); 2851 2852 for (unsigned n = 0; n < List.size(); n++) { 2853 const ArangeSpan &Span = List[n]; 2854 Asm->EmitLabelReference(Span.Start, PtrSize); 2855 2856 // Calculate the size as being from the span start to it's end. 2857 if (Span.End) { 2858 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize); 2859 } else { 2860 // For symbols without an end marker (e.g. common), we 2861 // write a single arange entry containing just that one symbol. 2862 uint64_t Size = SymSize[Span.Start]; 2863 if (Size == 0) 2864 Size = 1; 2865 2866 Asm->OutStreamer.EmitIntValue(Size, PtrSize); 2867 } 2868 } 2869 2870 Asm->OutStreamer.AddComment("ARange terminator"); 2871 Asm->OutStreamer.EmitIntValue(0, PtrSize); 2872 Asm->OutStreamer.EmitIntValue(0, PtrSize); 2873 } 2874} 2875 2876// Emit visible names into a debug ranges section. 2877void DwarfDebug::emitDebugRanges() { 2878 // Start the dwarf ranges section. 2879 Asm->OutStreamer 2880 .SwitchSection(Asm->getObjFileLowering().getDwarfRangesSection()); 2881 unsigned char Size = Asm->getDataLayout().getPointerSize(); 2882 for (SmallVectorImpl<const MCSymbol *>::iterator 2883 I = DebugRangeSymbols.begin(), E = DebugRangeSymbols.end(); 2884 I != E; ++I) { 2885 if (*I) 2886 Asm->OutStreamer.EmitSymbolValue(const_cast<MCSymbol*>(*I), Size); 2887 else 2888 Asm->OutStreamer.EmitIntValue(0, Size); 2889 } 2890} 2891 2892// Emit visible names into a debug macinfo section. 2893void DwarfDebug::emitDebugMacInfo() { 2894 if (const MCSection *LineInfo = 2895 Asm->getObjFileLowering().getDwarfMacroInfoSection()) { 2896 // Start the dwarf macinfo section. 2897 Asm->OutStreamer.SwitchSection(LineInfo); 2898 } 2899} 2900 2901// DWARF5 Experimental Separate Dwarf emitters. 2902 2903// This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list, 2904// DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id, 2905// DW_AT_ranges_base, DW_AT_addr_base. 2906CompileUnit *DwarfDebug::constructSkeletonCU(const CompileUnit *CU) { 2907 2908 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit); 2909 CompileUnit *NewCU = new CompileUnit(CU->getUniqueID(), Die, CU->getNode(), 2910 Asm, this, &SkeletonHolder); 2911 2912 NewCU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name, 2913 DICompileUnit(CU->getNode()).getSplitDebugFilename()); 2914 2915 // Relocate to the beginning of the addr_base section, else 0 for the 2916 // beginning of the one for this compile unit. 2917 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2918 NewCU->addLabel(Die, dwarf::DW_AT_GNU_addr_base, dwarf::DW_FORM_sec_offset, 2919 DwarfAddrSectionSym); 2920 else 2921 NewCU->addUInt(Die, dwarf::DW_AT_GNU_addr_base, 2922 dwarf::DW_FORM_sec_offset, 0); 2923 2924 // 2.17.1 requires that we use DW_AT_low_pc for a single entry point 2925 // into an entity. We're using 0, or a NULL label for this. 2926 NewCU->addUInt(Die, dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr, 0); 2927 2928 // DW_AT_stmt_list is a offset of line number information for this 2929 // compile unit in debug_line section. 2930 // FIXME: Should handle multiple compile units. 2931 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2932 NewCU->addLabel(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 2933 DwarfLineSectionSym); 2934 else 2935 NewCU->addUInt(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_sec_offset, 0); 2936 2937 if (!CompilationDir.empty()) 2938 NewCU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir); 2939 2940 // Flags to let the linker know we have emitted new style pubnames. 2941 if (GenerateGnuPubSections) { 2942 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2943 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_sec_offset, 2944 Asm->GetTempSymbol("gnu_pubnames", NewCU->getUniqueID())); 2945 else 2946 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubnames, dwarf::DW_FORM_data4, 2947 Asm->GetTempSymbol("gnu_pubnames", NewCU->getUniqueID()), 2948 DwarfGnuPubNamesSectionSym); 2949 2950 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2951 NewCU->addLabel(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_sec_offset, 2952 Asm->GetTempSymbol("gnu_pubtypes", NewCU->getUniqueID())); 2953 else 2954 NewCU->addDelta(Die, dwarf::DW_AT_GNU_pubtypes, dwarf::DW_FORM_data4, 2955 Asm->GetTempSymbol("gnu_pubtypes", NewCU->getUniqueID()), 2956 DwarfGnuPubTypesSectionSym); 2957 } 2958 2959 // Flag if we've emitted any ranges and their location for the compile unit. 2960 if (DebugRangeSymbols.size()) { 2961 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections()) 2962 NewCU->addLabel(Die, dwarf::DW_AT_GNU_ranges_base, 2963 dwarf::DW_FORM_sec_offset, DwarfDebugRangeSectionSym); 2964 else 2965 NewCU->addUInt(Die, dwarf::DW_AT_GNU_ranges_base, dwarf::DW_FORM_data4, 2966 0); 2967 } 2968 2969 SkeletonHolder.addUnit(NewCU); 2970 SkeletonCUs.push_back(NewCU); 2971 2972 return NewCU; 2973} 2974 2975void DwarfDebug::emitSkeletonAbbrevs(const MCSection *Section) { 2976 assert(useSplitDwarf() && "No split dwarf debug info?"); 2977 emitAbbrevs(Section, &SkeletonAbbrevs); 2978} 2979 2980// Emit the .debug_info.dwo section for separated dwarf. This contains the 2981// compile units that would normally be in debug_info. 2982void DwarfDebug::emitDebugInfoDWO() { 2983 assert(useSplitDwarf() && "No split dwarf debug info?"); 2984 InfoHolder.emitUnits(this, Asm->getObjFileLowering().getDwarfInfoDWOSection(), 2985 Asm->getObjFileLowering().getDwarfAbbrevDWOSection(), 2986 DwarfAbbrevDWOSectionSym); 2987} 2988 2989// Emit the .debug_abbrev.dwo section for separated dwarf. This contains the 2990// abbreviations for the .debug_info.dwo section. 2991void DwarfDebug::emitDebugAbbrevDWO() { 2992 assert(useSplitDwarf() && "No split dwarf?"); 2993 emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection(), 2994 &Abbreviations); 2995} 2996 2997// Emit the .debug_str.dwo section for separated dwarf. This contains the 2998// string section and is identical in format to traditional .debug_str 2999// sections. 3000void DwarfDebug::emitDebugStrDWO() { 3001 assert(useSplitDwarf() && "No split dwarf?"); 3002 const MCSection *OffSec = Asm->getObjFileLowering() 3003 .getDwarfStrOffDWOSection(); 3004 const MCSymbol *StrSym = DwarfStrSectionSym; 3005 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(), 3006 OffSec, StrSym); 3007} 3008