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Diffstat (limited to 'contrib/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp')
| -rw-r--r-- | contrib/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp | 2498 |
1 files changed, 2498 insertions, 0 deletions
diff --git a/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp new file mode 100644 index 0000000..ac1c0ff --- /dev/null +++ b/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp @@ -0,0 +1,2498 @@ +//===-- llvm/CodeGen/DwarfDebug.cpp - Dwarf Debug Framework ---------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file contains support for writing dwarf debug info into asm files. +// +//===----------------------------------------------------------------------===// + +#include "ByteStreamer.h" +#include "DwarfDebug.h" +#include "DIE.h" +#include "DIEHash.h" +#include "DwarfUnit.h" +#include "llvm/ADT/STLExtras.h" +#include "llvm/ADT/Statistic.h" +#include "llvm/ADT/StringExtras.h" +#include "llvm/ADT/Triple.h" +#include "llvm/CodeGen/MachineFunction.h" +#include "llvm/CodeGen/MachineModuleInfo.h" +#include "llvm/IR/Constants.h" +#include "llvm/IR/DIBuilder.h" +#include "llvm/IR/DataLayout.h" +#include "llvm/IR/DebugInfo.h" +#include "llvm/IR/Instructions.h" +#include "llvm/IR/Module.h" +#include "llvm/IR/ValueHandle.h" +#include "llvm/MC/MCAsmInfo.h" +#include "llvm/MC/MCSection.h" +#include "llvm/MC/MCStreamer.h" +#include "llvm/MC/MCSymbol.h" +#include "llvm/Support/CommandLine.h" +#include "llvm/Support/Debug.h" +#include "llvm/Support/Dwarf.h" +#include "llvm/Support/Endian.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/FormattedStream.h" +#include "llvm/Support/LEB128.h" +#include "llvm/Support/MD5.h" +#include "llvm/Support/Path.h" +#include "llvm/Support/Timer.h" +#include "llvm/Target/TargetFrameLowering.h" +#include "llvm/Target/TargetLoweringObjectFile.h" +#include "llvm/Target/TargetMachine.h" +#include "llvm/Target/TargetOptions.h" +#include "llvm/Target/TargetRegisterInfo.h" +using namespace llvm; + +#define DEBUG_TYPE "dwarfdebug" + +static cl::opt<bool> +DisableDebugInfoPrinting("disable-debug-info-print", cl::Hidden, + cl::desc("Disable debug info printing")); + +static cl::opt<bool> UnknownLocations( + "use-unknown-locations", cl::Hidden, + cl::desc("Make an absence of debug location information explicit."), + cl::init(false)); + +static cl::opt<bool> +GenerateGnuPubSections("generate-gnu-dwarf-pub-sections", cl::Hidden, + cl::desc("Generate GNU-style pubnames and pubtypes"), + cl::init(false)); + +static cl::opt<bool> GenerateARangeSection("generate-arange-section", + cl::Hidden, + cl::desc("Generate dwarf aranges"), + cl::init(false)); + +namespace { +enum DefaultOnOff { Default, Enable, Disable }; +} + +static cl::opt<DefaultOnOff> +DwarfAccelTables("dwarf-accel-tables", cl::Hidden, + cl::desc("Output prototype dwarf accelerator tables."), + cl::values(clEnumVal(Default, "Default for platform"), + clEnumVal(Enable, "Enabled"), + clEnumVal(Disable, "Disabled"), clEnumValEnd), + cl::init(Default)); + +static cl::opt<DefaultOnOff> +SplitDwarf("split-dwarf", cl::Hidden, + cl::desc("Output DWARF5 split debug info."), + cl::values(clEnumVal(Default, "Default for platform"), + clEnumVal(Enable, "Enabled"), + clEnumVal(Disable, "Disabled"), clEnumValEnd), + cl::init(Default)); + +static cl::opt<DefaultOnOff> +DwarfPubSections("generate-dwarf-pub-sections", cl::Hidden, + cl::desc("Generate DWARF pubnames and pubtypes sections"), + cl::values(clEnumVal(Default, "Default for platform"), + clEnumVal(Enable, "Enabled"), + clEnumVal(Disable, "Disabled"), clEnumValEnd), + cl::init(Default)); + +static const char *const DWARFGroupName = "DWARF Emission"; +static const char *const DbgTimerName = "DWARF Debug Writer"; + +//===----------------------------------------------------------------------===// + +/// resolve - Look in the DwarfDebug map for the MDNode that +/// corresponds to the reference. +template <typename T> T DbgVariable::resolve(DIRef<T> Ref) const { + return DD->resolve(Ref); +} + +bool DbgVariable::isBlockByrefVariable() const { + assert(Var.isVariable() && "Invalid complex DbgVariable!"); + return Var.isBlockByrefVariable(DD->getTypeIdentifierMap()); +} + +DIType DbgVariable::getType() const { + DIType Ty = Var.getType().resolve(DD->getTypeIdentifierMap()); + // FIXME: isBlockByrefVariable should be reformulated in terms of complex + // addresses instead. + if (Var.isBlockByrefVariable(DD->getTypeIdentifierMap())) { + /* Byref variables, in Blocks, are declared by the programmer as + "SomeType VarName;", but the compiler creates a + __Block_byref_x_VarName struct, and gives the variable VarName + either the struct, or a pointer to the struct, as its type. This + is necessary for various behind-the-scenes things the compiler + needs to do with by-reference variables in blocks. + + However, as far as the original *programmer* is concerned, the + variable should still have type 'SomeType', as originally declared. + + The following function dives into the __Block_byref_x_VarName + struct to find the original type of the variable. This will be + passed back to the code generating the type for the Debug + Information Entry for the variable 'VarName'. 'VarName' will then + have the original type 'SomeType' in its debug information. + + The original type 'SomeType' will be the type of the field named + 'VarName' inside the __Block_byref_x_VarName struct. + + NOTE: In order for this to not completely fail on the debugger + side, the Debug Information Entry for the variable VarName needs to + have a DW_AT_location that tells the debugger how to unwind through + the pointers and __Block_byref_x_VarName struct to find the actual + value of the variable. The function addBlockByrefType does this. */ + DIType subType = Ty; + uint16_t tag = Ty.getTag(); + + if (tag == dwarf::DW_TAG_pointer_type) + subType = resolve(DIDerivedType(Ty).getTypeDerivedFrom()); + + DIArray Elements = DICompositeType(subType).getTypeArray(); + for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) { + DIDerivedType DT(Elements.getElement(i)); + if (getName() == DT.getName()) + return (resolve(DT.getTypeDerivedFrom())); + } + } + return Ty; +} + +static LLVM_CONSTEXPR DwarfAccelTable::Atom TypeAtoms[] = { + DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4), + DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, dwarf::DW_FORM_data2), + DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, dwarf::DW_FORM_data1)}; + +DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M) + : Asm(A), MMI(Asm->MMI), FirstCU(nullptr), PrevLabel(nullptr), + GlobalRangeCount(0), InfoHolder(A, "info_string", DIEValueAllocator), + UsedNonDefaultText(false), + SkeletonHolder(A, "skel_string", DIEValueAllocator), + AccelNames(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, + dwarf::DW_FORM_data4)), + AccelObjC(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, + dwarf::DW_FORM_data4)), + AccelNamespace(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, + dwarf::DW_FORM_data4)), + AccelTypes(TypeAtoms) { + + DwarfInfoSectionSym = DwarfAbbrevSectionSym = DwarfStrSectionSym = nullptr; + DwarfDebugRangeSectionSym = DwarfDebugLocSectionSym = nullptr; + DwarfLineSectionSym = nullptr; + DwarfAddrSectionSym = nullptr; + DwarfAbbrevDWOSectionSym = DwarfStrDWOSectionSym = nullptr; + FunctionBeginSym = FunctionEndSym = nullptr; + CurFn = nullptr; + CurMI = nullptr; + + // Turn on accelerator tables for Darwin by default, pubnames by + // default for non-Darwin, and handle split dwarf. + bool IsDarwin = Triple(A->getTargetTriple()).isOSDarwin(); + + if (DwarfAccelTables == Default) + HasDwarfAccelTables = IsDarwin; + else + HasDwarfAccelTables = DwarfAccelTables == Enable; + + if (SplitDwarf == Default) + HasSplitDwarf = false; + else + HasSplitDwarf = SplitDwarf == Enable; + + if (DwarfPubSections == Default) + HasDwarfPubSections = !IsDarwin; + else + HasDwarfPubSections = DwarfPubSections == Enable; + + unsigned DwarfVersionNumber = Asm->TM.Options.MCOptions.DwarfVersion; + DwarfVersion = DwarfVersionNumber ? DwarfVersionNumber + : MMI->getModule()->getDwarfVersion(); + + Asm->OutStreamer.getContext().setDwarfVersion(DwarfVersion); + + { + NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled); + beginModule(); + } +} + +// Define out of line so we don't have to include DwarfUnit.h in DwarfDebug.h. +DwarfDebug::~DwarfDebug() { } + +// Switch to the specified MCSection and emit an assembler +// temporary label to it if SymbolStem is specified. +static MCSymbol *emitSectionSym(AsmPrinter *Asm, const MCSection *Section, + const char *SymbolStem = nullptr) { + Asm->OutStreamer.SwitchSection(Section); + if (!SymbolStem) + return nullptr; + + MCSymbol *TmpSym = Asm->GetTempSymbol(SymbolStem); + Asm->OutStreamer.EmitLabel(TmpSym); + return TmpSym; +} + +static bool isObjCClass(StringRef Name) { + return Name.startswith("+") || Name.startswith("-"); +} + +static bool hasObjCCategory(StringRef Name) { + if (!isObjCClass(Name)) + return false; + + return Name.find(") ") != StringRef::npos; +} + +static void getObjCClassCategory(StringRef In, StringRef &Class, + StringRef &Category) { + if (!hasObjCCategory(In)) { + Class = In.slice(In.find('[') + 1, In.find(' ')); + Category = ""; + return; + } + + Class = In.slice(In.find('[') + 1, In.find('(')); + Category = In.slice(In.find('[') + 1, In.find(' ')); + return; +} + +static StringRef getObjCMethodName(StringRef In) { + return In.slice(In.find(' ') + 1, In.find(']')); +} + +// Helper for sorting sections into a stable output order. +static bool SectionSort(const MCSection *A, const MCSection *B) { + std::string LA = (A ? A->getLabelBeginName() : ""); + std::string LB = (B ? B->getLabelBeginName() : ""); + return LA < LB; +} + +// Add the various names to the Dwarf accelerator table names. +// TODO: Determine whether or not we should add names for programs +// that do not have a DW_AT_name or DW_AT_linkage_name field - this +// is only slightly different than the lookup of non-standard ObjC names. +void DwarfDebug::addSubprogramNames(DISubprogram SP, DIE &Die) { + if (!SP.isDefinition()) + return; + addAccelName(SP.getName(), Die); + + // If the linkage name is different than the name, go ahead and output + // that as well into the name table. + if (SP.getLinkageName() != "" && SP.getName() != SP.getLinkageName()) + addAccelName(SP.getLinkageName(), Die); + + // If this is an Objective-C selector name add it to the ObjC accelerator + // too. + if (isObjCClass(SP.getName())) { + StringRef Class, Category; + getObjCClassCategory(SP.getName(), Class, Category); + addAccelObjC(Class, Die); + if (Category != "") + addAccelObjC(Category, Die); + // Also add the base method name to the name table. + addAccelName(getObjCMethodName(SP.getName()), Die); + } +} + +/// isSubprogramContext - Return true if Context is either a subprogram +/// or another context nested inside a subprogram. +bool DwarfDebug::isSubprogramContext(const MDNode *Context) { + if (!Context) + return false; + DIDescriptor D(Context); + if (D.isSubprogram()) + return true; + if (D.isType()) + return isSubprogramContext(resolve(DIType(Context).getContext())); + return false; +} + +// Find DIE for the given subprogram and attach appropriate DW_AT_low_pc +// and DW_AT_high_pc attributes. If there are global variables in this +// scope then create and insert DIEs for these variables. +DIE &DwarfDebug::updateSubprogramScopeDIE(DwarfCompileUnit &SPCU, + DISubprogram SP) { + DIE *SPDie = SPCU.getOrCreateSubprogramDIE(SP); + + attachLowHighPC(SPCU, *SPDie, FunctionBeginSym, FunctionEndSym); + + const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo(); + MachineLocation Location(RI->getFrameRegister(*Asm->MF)); + SPCU.addAddress(*SPDie, dwarf::DW_AT_frame_base, Location); + + // Add name to the name table, we do this here because we're guaranteed + // to have concrete versions of our DW_TAG_subprogram nodes. + addSubprogramNames(SP, *SPDie); + + return *SPDie; +} + +/// Check whether we should create a DIE for the given Scope, return true +/// if we don't create a DIE (the corresponding DIE is null). +bool DwarfDebug::isLexicalScopeDIENull(LexicalScope *Scope) { + if (Scope->isAbstractScope()) + return false; + + // We don't create a DIE if there is no Range. + const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges(); + if (Ranges.empty()) + return true; + + if (Ranges.size() > 1) + return false; + + // We don't create a DIE if we have a single Range and the end label + // is null. + SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(); + MCSymbol *End = getLabelAfterInsn(RI->second); + return !End; +} + +static void addSectionLabel(AsmPrinter &Asm, DwarfUnit &U, DIE &D, + dwarf::Attribute A, const MCSymbol *L, + const MCSymbol *Sec) { + if (Asm.MAI->doesDwarfUseRelocationsAcrossSections()) + U.addSectionLabel(D, A, L); + else + U.addSectionDelta(D, A, L, Sec); +} + +void DwarfDebug::addScopeRangeList(DwarfCompileUnit &TheCU, DIE &ScopeDIE, + const SmallVectorImpl<InsnRange> &Range) { + // Emit offset in .debug_range as a relocatable label. emitDIE will handle + // emitting it appropriately. + MCSymbol *RangeSym = Asm->GetTempSymbol("debug_ranges", GlobalRangeCount++); + + // Under fission, ranges are specified by constant offsets relative to the + // CU's DW_AT_GNU_ranges_base. + if (useSplitDwarf()) + TheCU.addSectionDelta(ScopeDIE, dwarf::DW_AT_ranges, RangeSym, + DwarfDebugRangeSectionSym); + else + addSectionLabel(*Asm, TheCU, ScopeDIE, dwarf::DW_AT_ranges, RangeSym, + DwarfDebugRangeSectionSym); + + RangeSpanList List(RangeSym); + for (const InsnRange &R : Range) { + RangeSpan Span(getLabelBeforeInsn(R.first), getLabelAfterInsn(R.second)); + List.addRange(std::move(Span)); + } + + // Add the range list to the set of ranges to be emitted. + TheCU.addRangeList(std::move(List)); +} + +void DwarfDebug::attachRangesOrLowHighPC(DwarfCompileUnit &TheCU, DIE &Die, + const SmallVectorImpl<InsnRange> &Ranges) { + assert(!Ranges.empty()); + if (Ranges.size() == 1) + attachLowHighPC(TheCU, Die, getLabelBeforeInsn(Ranges.front().first), + getLabelAfterInsn(Ranges.front().second)); + else + addScopeRangeList(TheCU, Die, Ranges); +} + +// Construct new DW_TAG_lexical_block for this scope and attach +// DW_AT_low_pc/DW_AT_high_pc labels. +std::unique_ptr<DIE> +DwarfDebug::constructLexicalScopeDIE(DwarfCompileUnit &TheCU, + LexicalScope *Scope) { + if (isLexicalScopeDIENull(Scope)) + return nullptr; + + auto ScopeDIE = make_unique<DIE>(dwarf::DW_TAG_lexical_block); + if (Scope->isAbstractScope()) + return ScopeDIE; + + attachRangesOrLowHighPC(TheCU, *ScopeDIE, Scope->getRanges()); + + return ScopeDIE; +} + +// This scope represents inlined body of a function. Construct DIE to +// represent this concrete inlined copy of the function. +std::unique_ptr<DIE> +DwarfDebug::constructInlinedScopeDIE(DwarfCompileUnit &TheCU, + LexicalScope *Scope) { + assert(Scope->getScopeNode()); + DIScope DS(Scope->getScopeNode()); + DISubprogram InlinedSP = getDISubprogram(DS); + // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram + // was inlined from another compile unit. + DIE *OriginDIE = AbstractSPDies[InlinedSP]; + assert(OriginDIE && "Unable to find original DIE for an inlined subprogram."); + + auto ScopeDIE = make_unique<DIE>(dwarf::DW_TAG_inlined_subroutine); + TheCU.addDIEEntry(*ScopeDIE, dwarf::DW_AT_abstract_origin, *OriginDIE); + + attachRangesOrLowHighPC(TheCU, *ScopeDIE, Scope->getRanges()); + + InlinedSubprogramDIEs.insert(OriginDIE); + + // Add the call site information to the DIE. + DILocation DL(Scope->getInlinedAt()); + TheCU.addUInt(*ScopeDIE, dwarf::DW_AT_call_file, None, + TheCU.getOrCreateSourceID(DL.getFilename(), DL.getDirectory())); + TheCU.addUInt(*ScopeDIE, dwarf::DW_AT_call_line, None, DL.getLineNumber()); + + // Add name to the name table, we do this here because we're guaranteed + // to have concrete versions of our DW_TAG_inlined_subprogram nodes. + addSubprogramNames(InlinedSP, *ScopeDIE); + + return ScopeDIE; +} + +static std::unique_ptr<DIE> constructVariableDIE(DwarfCompileUnit &TheCU, + DbgVariable &DV, + const LexicalScope &Scope, + DIE *&ObjectPointer) { + auto Var = TheCU.constructVariableDIE(DV, Scope.isAbstractScope()); + if (DV.isObjectPointer()) + ObjectPointer = Var.get(); + return Var; +} + +DIE *DwarfDebug::createScopeChildrenDIE( + DwarfCompileUnit &TheCU, LexicalScope *Scope, + SmallVectorImpl<std::unique_ptr<DIE>> &Children) { + DIE *ObjectPointer = nullptr; + + // Collect arguments for current function. + if (LScopes.isCurrentFunctionScope(Scope)) { + for (DbgVariable *ArgDV : CurrentFnArguments) + if (ArgDV) + Children.push_back( + constructVariableDIE(TheCU, *ArgDV, *Scope, ObjectPointer)); + + // If this is a variadic function, add an unspecified parameter. + DISubprogram SP(Scope->getScopeNode()); + DIArray FnArgs = SP.getType().getTypeArray(); + if (FnArgs.getElement(FnArgs.getNumElements() - 1) + .isUnspecifiedParameter()) { + Children.push_back( + make_unique<DIE>(dwarf::DW_TAG_unspecified_parameters)); + } + } + + // Collect lexical scope children first. + for (DbgVariable *DV : ScopeVariables.lookup(Scope)) + Children.push_back(constructVariableDIE(TheCU, *DV, *Scope, ObjectPointer)); + + for (LexicalScope *LS : Scope->getChildren()) + if (std::unique_ptr<DIE> Nested = constructScopeDIE(TheCU, LS)) + Children.push_back(std::move(Nested)); + return ObjectPointer; +} + +void DwarfDebug::createAndAddScopeChildren(DwarfCompileUnit &TheCU, + LexicalScope *Scope, DIE &ScopeDIE) { + // We create children when the scope DIE is not null. + SmallVector<std::unique_ptr<DIE>, 8> Children; + if (DIE *ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children)) + TheCU.addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, *ObjectPointer); + + // Add children + for (auto &I : Children) + ScopeDIE.addChild(std::move(I)); +} + +void DwarfDebug::constructAbstractSubprogramScopeDIE(DwarfCompileUnit &TheCU, + LexicalScope *Scope) { + assert(Scope && Scope->getScopeNode()); + assert(Scope->isAbstractScope()); + assert(!Scope->getInlinedAt()); + + DISubprogram SP(Scope->getScopeNode()); + + ProcessedSPNodes.insert(SP); + + DIE *&AbsDef = AbstractSPDies[SP]; + if (AbsDef) + return; + + // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram + // was inlined from another compile unit. + DwarfCompileUnit &SPCU = *SPMap[SP]; + DIE *ContextDIE; + + // Some of this is duplicated from DwarfUnit::getOrCreateSubprogramDIE, with + // the important distinction that the DIDescriptor is not associated with the + // DIE (since the DIDescriptor will be associated with the concrete DIE, if + // any). It could be refactored to some common utility function. + if (DISubprogram SPDecl = SP.getFunctionDeclaration()) { + ContextDIE = &SPCU.getUnitDie(); + SPCU.getOrCreateSubprogramDIE(SPDecl); + } else + ContextDIE = SPCU.getOrCreateContextDIE(resolve(SP.getContext())); + + // Passing null as the associated DIDescriptor because the abstract definition + // shouldn't be found by lookup. + AbsDef = &SPCU.createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE, + DIDescriptor()); + SPCU.applySubprogramAttributesToDefinition(SP, *AbsDef); + + SPCU.addUInt(*AbsDef, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined); + createAndAddScopeChildren(SPCU, Scope, *AbsDef); +} + +DIE &DwarfDebug::constructSubprogramScopeDIE(DwarfCompileUnit &TheCU, + LexicalScope *Scope) { + assert(Scope && Scope->getScopeNode()); + assert(!Scope->getInlinedAt()); + assert(!Scope->isAbstractScope()); + DISubprogram Sub(Scope->getScopeNode()); + + assert(Sub.isSubprogram()); + + ProcessedSPNodes.insert(Sub); + + DIE &ScopeDIE = updateSubprogramScopeDIE(TheCU, Sub); + + createAndAddScopeChildren(TheCU, Scope, ScopeDIE); + + return ScopeDIE; +} + +// Construct a DIE for this scope. +std::unique_ptr<DIE> DwarfDebug::constructScopeDIE(DwarfCompileUnit &TheCU, + LexicalScope *Scope) { + if (!Scope || !Scope->getScopeNode()) + return nullptr; + + DIScope DS(Scope->getScopeNode()); + + assert((Scope->getInlinedAt() || !DS.isSubprogram()) && + "Only handle inlined subprograms here, use " + "constructSubprogramScopeDIE for non-inlined " + "subprograms"); + + SmallVector<std::unique_ptr<DIE>, 8> Children; + + // We try to create the scope DIE first, then the children DIEs. This will + // avoid creating un-used children then removing them later when we find out + // the scope DIE is null. + std::unique_ptr<DIE> ScopeDIE; + if (Scope->getParent() && DS.isSubprogram()) { + ScopeDIE = constructInlinedScopeDIE(TheCU, Scope); + if (!ScopeDIE) + return nullptr; + // We create children when the scope DIE is not null. + createScopeChildrenDIE(TheCU, Scope, Children); + } else { + // Early exit when we know the scope DIE is going to be null. + if (isLexicalScopeDIENull(Scope)) + return nullptr; + + // We create children here when we know the scope DIE is not going to be + // null and the children will be added to the scope DIE. + createScopeChildrenDIE(TheCU, Scope, Children); + + // There is no need to emit empty lexical block DIE. + std::pair<ImportedEntityMap::const_iterator, + ImportedEntityMap::const_iterator> Range = + std::equal_range(ScopesWithImportedEntities.begin(), + ScopesWithImportedEntities.end(), + std::pair<const MDNode *, const MDNode *>(DS, nullptr), + less_first()); + if (Children.empty() && Range.first == Range.second) + return nullptr; + ScopeDIE = constructLexicalScopeDIE(TheCU, Scope); + assert(ScopeDIE && "Scope DIE should not be null."); + for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second; + ++i) + constructImportedEntityDIE(TheCU, i->second, *ScopeDIE); + } + + // Add children + for (auto &I : Children) + ScopeDIE->addChild(std::move(I)); + + return ScopeDIE; +} + +void DwarfDebug::addGnuPubAttributes(DwarfUnit &U, DIE &D) const { + if (!GenerateGnuPubSections) + return; + + U.addFlag(D, dwarf::DW_AT_GNU_pubnames); +} + +// Create new DwarfCompileUnit for the given metadata node with tag +// DW_TAG_compile_unit. +DwarfCompileUnit &DwarfDebug::constructDwarfCompileUnit(DICompileUnit DIUnit) { + StringRef FN = DIUnit.getFilename(); + CompilationDir = DIUnit.getDirectory(); + + auto OwnedUnit = make_unique<DwarfCompileUnit>( + InfoHolder.getUnits().size(), DIUnit, Asm, this, &InfoHolder); + DwarfCompileUnit &NewCU = *OwnedUnit; + DIE &Die = NewCU.getUnitDie(); + InfoHolder.addUnit(std::move(OwnedUnit)); + + // LTO with assembly output shares a single line table amongst multiple CUs. + // To avoid the compilation directory being ambiguous, let the line table + // explicitly describe the directory of all files, never relying on the + // compilation directory. + if (!Asm->OutStreamer.hasRawTextSupport() || SingleCU) + Asm->OutStreamer.getContext().setMCLineTableCompilationDir( + NewCU.getUniqueID(), CompilationDir); + + NewCU.addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer()); + NewCU.addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2, + DIUnit.getLanguage()); + NewCU.addString(Die, dwarf::DW_AT_name, FN); + + if (!useSplitDwarf()) { + NewCU.initStmtList(DwarfLineSectionSym); + + // If we're using split dwarf the compilation dir is going to be in the + // skeleton CU and so we don't need to duplicate it here. + if (!CompilationDir.empty()) + NewCU.addString(Die, dwarf::DW_AT_comp_dir, CompilationDir); + + addGnuPubAttributes(NewCU, Die); + } + + if (DIUnit.isOptimized()) + NewCU.addFlag(Die, dwarf::DW_AT_APPLE_optimized); + + StringRef Flags = DIUnit.getFlags(); + if (!Flags.empty()) + NewCU.addString(Die, dwarf::DW_AT_APPLE_flags, Flags); + + if (unsigned RVer = DIUnit.getRunTimeVersion()) + NewCU.addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers, + dwarf::DW_FORM_data1, RVer); + + if (!FirstCU) + FirstCU = &NewCU; + + if (useSplitDwarf()) { + NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoDWOSection(), + DwarfInfoDWOSectionSym); + NewCU.setSkeleton(constructSkeletonCU(NewCU)); + } else + NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(), + DwarfInfoSectionSym); + + CUMap.insert(std::make_pair(DIUnit, &NewCU)); + CUDieMap.insert(std::make_pair(&Die, &NewCU)); + return NewCU; +} + +void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU, + const MDNode *N) { + DIImportedEntity Module(N); + assert(Module.Verify()); + if (DIE *D = TheCU.getOrCreateContextDIE(Module.getContext())) + constructImportedEntityDIE(TheCU, Module, *D); +} + +void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU, + const MDNode *N, DIE &Context) { + DIImportedEntity Module(N); + assert(Module.Verify()); + return constructImportedEntityDIE(TheCU, Module, Context); +} + +void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU, + const DIImportedEntity &Module, + DIE &Context) { + assert(Module.Verify() && + "Use one of the MDNode * overloads to handle invalid metadata"); + DIE &IMDie = TheCU.createAndAddDIE(Module.getTag(), Context, Module); + DIE *EntityDie; + DIDescriptor Entity = resolve(Module.getEntity()); + if (Entity.isNameSpace()) + EntityDie = TheCU.getOrCreateNameSpace(DINameSpace(Entity)); + else if (Entity.isSubprogram()) + EntityDie = TheCU.getOrCreateSubprogramDIE(DISubprogram(Entity)); + else if (Entity.isType()) + EntityDie = TheCU.getOrCreateTypeDIE(DIType(Entity)); + else + EntityDie = TheCU.getDIE(Entity); + TheCU.addSourceLine(IMDie, Module.getLineNumber(), + Module.getContext().getFilename(), + Module.getContext().getDirectory()); + TheCU.addDIEEntry(IMDie, dwarf::DW_AT_import, *EntityDie); + StringRef Name = Module.getName(); + if (!Name.empty()) + TheCU.addString(IMDie, dwarf::DW_AT_name, Name); +} + +// Emit all Dwarf sections that should come prior to the content. Create +// global DIEs and emit initial debug info sections. This is invoked by +// the target AsmPrinter. +void DwarfDebug::beginModule() { + if (DisableDebugInfoPrinting) + return; + + const Module *M = MMI->getModule(); + + // If module has named metadata anchors then use them, otherwise scan the + // module using debug info finder to collect debug info. + NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu"); + if (!CU_Nodes) + return; + TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes); + + // Emit initial sections so we can reference labels later. + emitSectionLabels(); + + SingleCU = CU_Nodes->getNumOperands() == 1; + + for (MDNode *N : CU_Nodes->operands()) { + DICompileUnit CUNode(N); + DwarfCompileUnit &CU = constructDwarfCompileUnit(CUNode); + DIArray ImportedEntities = CUNode.getImportedEntities(); + for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i) + ScopesWithImportedEntities.push_back(std::make_pair( + DIImportedEntity(ImportedEntities.getElement(i)).getContext(), + ImportedEntities.getElement(i))); + std::sort(ScopesWithImportedEntities.begin(), + ScopesWithImportedEntities.end(), less_first()); + DIArray GVs = CUNode.getGlobalVariables(); + for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i) + CU.createGlobalVariableDIE(DIGlobalVariable(GVs.getElement(i))); + DIArray SPs = CUNode.getSubprograms(); + for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) + SPMap.insert(std::make_pair(SPs.getElement(i), &CU)); + DIArray EnumTypes = CUNode.getEnumTypes(); + for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i) + CU.getOrCreateTypeDIE(EnumTypes.getElement(i)); + DIArray RetainedTypes = CUNode.getRetainedTypes(); + for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i) { + DIType Ty(RetainedTypes.getElement(i)); + // The retained types array by design contains pointers to + // MDNodes rather than DIRefs. Unique them here. + DIType UniqueTy(resolve(Ty.getRef())); + CU.getOrCreateTypeDIE(UniqueTy); + } + // Emit imported_modules last so that the relevant context is already + // available. + for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i) + constructImportedEntityDIE(CU, ImportedEntities.getElement(i)); + } + + // Tell MMI that we have debug info. + MMI->setDebugInfoAvailability(true); + + // Prime section data. + SectionMap[Asm->getObjFileLowering().getTextSection()]; +} + +void DwarfDebug::finishVariableDefinitions() { + for (const auto &Var : ConcreteVariables) { + DIE *VariableDie = Var->getDIE(); + // FIXME: There shouldn't be any variables without DIEs. + if (!VariableDie) + continue; + // FIXME: Consider the time-space tradeoff of just storing the unit pointer + // in the ConcreteVariables list, rather than looking it up again here. + // DIE::getUnit isn't simple - it walks parent pointers, etc. + DwarfCompileUnit *Unit = lookupUnit(VariableDie->getUnit()); + assert(Unit); + DbgVariable *AbsVar = getExistingAbstractVariable(Var->getVariable()); + if (AbsVar && AbsVar->getDIE()) { + Unit->addDIEEntry(*VariableDie, dwarf::DW_AT_abstract_origin, + *AbsVar->getDIE()); + } else + Unit->applyVariableAttributes(*Var, *VariableDie); + } +} + +void DwarfDebug::finishSubprogramDefinitions() { + const Module *M = MMI->getModule(); + + NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu"); + for (MDNode *N : CU_Nodes->operands()) { + DICompileUnit TheCU(N); + // Construct subprogram DIE and add variables DIEs. + DwarfCompileUnit *SPCU = + static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU)); + DIArray Subprograms = TheCU.getSubprograms(); + for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) { + DISubprogram SP(Subprograms.getElement(i)); + // Perhaps the subprogram is in another CU (such as due to comdat + // folding, etc), in which case ignore it here. + if (SPMap[SP] != SPCU) + continue; + DIE *D = SPCU->getDIE(SP); + if (DIE *AbsSPDIE = AbstractSPDies.lookup(SP)) { + if (D) + // If this subprogram has an abstract definition, reference that + SPCU->addDIEEntry(*D, dwarf::DW_AT_abstract_origin, *AbsSPDIE); + } else { + if (!D) + // Lazily construct the subprogram if we didn't see either concrete or + // inlined versions during codegen. + D = SPCU->getOrCreateSubprogramDIE(SP); + // And attach the attributes + SPCU->applySubprogramAttributesToDefinition(SP, *D); + } + } + } +} + + +// Collect info for variables that were optimized out. +void DwarfDebug::collectDeadVariables() { + const Module *M = MMI->getModule(); + + if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) { + for (MDNode *N : CU_Nodes->operands()) { + DICompileUnit TheCU(N); + // Construct subprogram DIE and add variables DIEs. + DwarfCompileUnit *SPCU = + static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU)); + assert(SPCU && "Unable to find Compile Unit!"); + DIArray Subprograms = TheCU.getSubprograms(); + for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) { + DISubprogram SP(Subprograms.getElement(i)); + if (ProcessedSPNodes.count(SP) != 0) + continue; + assert(SP.isSubprogram() && + "CU's subprogram list contains a non-subprogram"); + assert(SP.isDefinition() && + "CU's subprogram list contains a subprogram declaration"); + DIArray Variables = SP.getVariables(); + if (Variables.getNumElements() == 0) + continue; + + DIE *SPDIE = AbstractSPDies.lookup(SP); + if (!SPDIE) + SPDIE = SPCU->getDIE(SP); + assert(SPDIE); + for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) { + DIVariable DV(Variables.getElement(vi)); + assert(DV.isVariable()); + DbgVariable NewVar(DV, this); + auto VariableDie = SPCU->constructVariableDIE(NewVar); + SPCU->applyVariableAttributes(NewVar, *VariableDie); + SPDIE->addChild(std::move(VariableDie)); + } + } + } + } +} + +void DwarfDebug::finalizeModuleInfo() { + finishSubprogramDefinitions(); + + finishVariableDefinitions(); + + // Collect info for variables that were optimized out. + collectDeadVariables(); + + // Handle anything that needs to be done on a per-unit basis after + // all other generation. + for (const auto &TheU : getUnits()) { + // Emit DW_AT_containing_type attribute to connect types with their + // vtable holding type. + TheU->constructContainingTypeDIEs(); + + // Add CU specific attributes if we need to add any. + if (TheU->getUnitDie().getTag() == dwarf::DW_TAG_compile_unit) { + // If we're splitting the dwarf out now that we've got the entire + // CU then add the dwo id to it. + DwarfCompileUnit *SkCU = + static_cast<DwarfCompileUnit *>(TheU->getSkeleton()); + if (useSplitDwarf()) { + // Emit a unique identifier for this CU. + uint64_t ID = DIEHash(Asm).computeCUSignature(TheU->getUnitDie()); + TheU->addUInt(TheU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id, + dwarf::DW_FORM_data8, ID); + SkCU->addUInt(SkCU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id, + dwarf::DW_FORM_data8, ID); + + // We don't keep track of which addresses are used in which CU so this + // is a bit pessimistic under LTO. + if (!AddrPool.isEmpty()) + addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(), + dwarf::DW_AT_GNU_addr_base, DwarfAddrSectionSym, + DwarfAddrSectionSym); + if (!TheU->getRangeLists().empty()) + addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(), + dwarf::DW_AT_GNU_ranges_base, + DwarfDebugRangeSectionSym, DwarfDebugRangeSectionSym); + } + + // If we have code split among multiple sections or non-contiguous + // ranges of code then emit a DW_AT_ranges attribute on the unit that will + // remain in the .o file, otherwise add a DW_AT_low_pc. + // FIXME: We should use ranges allow reordering of code ala + // .subsections_via_symbols in mach-o. This would mean turning on + // ranges for all subprogram DIEs for mach-o. + DwarfCompileUnit &U = + SkCU ? *SkCU : static_cast<DwarfCompileUnit &>(*TheU); + unsigned NumRanges = TheU->getRanges().size(); + if (NumRanges) { + if (NumRanges > 1) { + addSectionLabel(*Asm, U, U.getUnitDie(), dwarf::DW_AT_ranges, + Asm->GetTempSymbol("cu_ranges", U.getUniqueID()), + DwarfDebugRangeSectionSym); + + // A DW_AT_low_pc attribute may also be specified in combination with + // DW_AT_ranges to specify the default base address for use in + // location lists (see Section 2.6.2) and range lists (see Section + // 2.17.3). + U.addUInt(U.getUnitDie(), dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr, + 0); + } else { + RangeSpan &Range = TheU->getRanges().back(); + U.addLocalLabelAddress(U.getUnitDie(), dwarf::DW_AT_low_pc, + Range.getStart()); + U.addLabelDelta(U.getUnitDie(), dwarf::DW_AT_high_pc, Range.getEnd(), + Range.getStart()); + } + } + } + } + + // Compute DIE offsets and sizes. + InfoHolder.computeSizeAndOffsets(); + if (useSplitDwarf()) + SkeletonHolder.computeSizeAndOffsets(); +} + +void DwarfDebug::endSections() { + // Filter labels by section. + for (const SymbolCU &SCU : ArangeLabels) { + if (SCU.Sym->isInSection()) { + // Make a note of this symbol and it's section. + const MCSection *Section = &SCU.Sym->getSection(); + if (!Section->getKind().isMetadata()) + SectionMap[Section].push_back(SCU); + } else { + // Some symbols (e.g. common/bss on mach-o) can have no section but still + // appear in the output. This sucks as we rely on sections to build + // arange spans. We can do it without, but it's icky. + SectionMap[nullptr].push_back(SCU); + } + } + + // Build a list of sections used. + std::vector<const MCSection *> Sections; + for (const auto &it : SectionMap) { + const MCSection *Section = it.first; + Sections.push_back(Section); + } + + // Sort the sections into order. + // This is only done to ensure consistent output order across different runs. + std::sort(Sections.begin(), Sections.end(), SectionSort); + + // Add terminating symbols for each section. + for (unsigned ID = 0, E = Sections.size(); ID != E; ID++) { + const MCSection *Section = Sections[ID]; + MCSymbol *Sym = nullptr; + + if (Section) { + // We can't call MCSection::getLabelEndName, as it's only safe to do so + // if we know the section name up-front. For user-created sections, the + // resulting label may not be valid to use as a label. (section names can + // use a greater set of characters on some systems) + Sym = Asm->GetTempSymbol("debug_end", ID); + Asm->OutStreamer.SwitchSection(Section); + Asm->OutStreamer.EmitLabel(Sym); + } + + // Insert a final terminator. + SectionMap[Section].push_back(SymbolCU(nullptr, Sym)); + } +} + +// Emit all Dwarf sections that should come after the content. +void DwarfDebug::endModule() { + assert(CurFn == nullptr); + assert(CurMI == nullptr); + + if (!FirstCU) + return; + + // End any existing sections. + // TODO: Does this need to happen? + endSections(); + + // Finalize the debug info for the module. + finalizeModuleInfo(); + + emitDebugStr(); + + // Emit all the DIEs into a debug info section. + emitDebugInfo(); + + // Corresponding abbreviations into a abbrev section. + emitAbbreviations(); + + // Emit info into a debug aranges section. + if (GenerateARangeSection) + emitDebugARanges(); + + // Emit info into a debug ranges section. + emitDebugRanges(); + + if (useSplitDwarf()) { + emitDebugStrDWO(); + emitDebugInfoDWO(); + emitDebugAbbrevDWO(); + emitDebugLineDWO(); + emitDebugLocDWO(); + // Emit DWO addresses. + AddrPool.emit(*Asm, Asm->getObjFileLowering().getDwarfAddrSection()); + } else + // Emit info into a debug loc section. + emitDebugLoc(); + + // Emit info into the dwarf accelerator table sections. + if (useDwarfAccelTables()) { + emitAccelNames(); + emitAccelObjC(); + emitAccelNamespaces(); + emitAccelTypes(); + } + + // Emit the pubnames and pubtypes sections if requested. + if (HasDwarfPubSections) { + emitDebugPubNames(GenerateGnuPubSections); + emitDebugPubTypes(GenerateGnuPubSections); + } + + // clean up. + SPMap.clear(); + AbstractVariables.clear(); + + // Reset these for the next Module if we have one. + FirstCU = nullptr; +} + +// Find abstract variable, if any, associated with Var. +DbgVariable *DwarfDebug::getExistingAbstractVariable(const DIVariable &DV, + DIVariable &Cleansed) { + LLVMContext &Ctx = DV->getContext(); + // More then one inlined variable corresponds to one abstract variable. + // FIXME: This duplication of variables when inlining should probably be + // removed. It's done to allow each DIVariable to describe its location + // because the DebugLoc on the dbg.value/declare isn't accurate. We should + // make it accurate then remove this duplication/cleansing stuff. + Cleansed = cleanseInlinedVariable(DV, Ctx); + auto I = AbstractVariables.find(Cleansed); + if (I != AbstractVariables.end()) + return I->second.get(); + return nullptr; +} + +DbgVariable *DwarfDebug::getExistingAbstractVariable(const DIVariable &DV) { + DIVariable Cleansed; + return getExistingAbstractVariable(DV, Cleansed); +} + +void DwarfDebug::createAbstractVariable(const DIVariable &Var, + LexicalScope *Scope) { + auto AbsDbgVariable = make_unique<DbgVariable>(Var, this); + addScopeVariable(Scope, AbsDbgVariable.get()); + AbstractVariables[Var] = std::move(AbsDbgVariable); +} + +void DwarfDebug::ensureAbstractVariableIsCreated(const DIVariable &DV, + const MDNode *ScopeNode) { + DIVariable Cleansed = DV; + if (getExistingAbstractVariable(DV, Cleansed)) + return; + + createAbstractVariable(Cleansed, LScopes.getOrCreateAbstractScope(ScopeNode)); +} + +void +DwarfDebug::ensureAbstractVariableIsCreatedIfScoped(const DIVariable &DV, + const MDNode *ScopeNode) { + DIVariable Cleansed = DV; + if (getExistingAbstractVariable(DV, Cleansed)) + return; + + if (LexicalScope *Scope = LScopes.findAbstractScope(ScopeNode)) + createAbstractVariable(Cleansed, Scope); +} + +// If Var is a current function argument then add it to CurrentFnArguments list. +bool DwarfDebug::addCurrentFnArgument(DbgVariable *Var, LexicalScope *Scope) { + if (!LScopes.isCurrentFunctionScope(Scope)) + return false; + DIVariable DV = Var->getVariable(); + if (DV.getTag() != dwarf::DW_TAG_arg_variable) + return false; + unsigned ArgNo = DV.getArgNumber(); + if (ArgNo == 0) + return false; + + size_t Size = CurrentFnArguments.size(); + if (Size == 0) + CurrentFnArguments.resize(CurFn->getFunction()->arg_size()); + // llvm::Function argument size is not good indicator of how many + // arguments does the function have at source level. + if (ArgNo > Size) + CurrentFnArguments.resize(ArgNo * 2); + CurrentFnArguments[ArgNo - 1] = Var; + return true; +} + +// Collect variable information from side table maintained by MMI. +void DwarfDebug::collectVariableInfoFromMMITable( + SmallPtrSet<const MDNode *, 16> &Processed) { + for (const auto &VI : MMI->getVariableDbgInfo()) { + if (!VI.Var) + continue; + Processed.insert(VI.Var); + DIVariable DV(VI.Var); + LexicalScope *Scope = LScopes.findLexicalScope(VI.Loc); + + // If variable scope is not found then skip this variable. + if (!Scope) + continue; + + ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode()); + ConcreteVariables.push_back(make_unique<DbgVariable>(DV, this)); + DbgVariable *RegVar = ConcreteVariables.back().get(); + RegVar->setFrameIndex(VI.Slot); + addScopeVariable(Scope, RegVar); + } +} + +// Get .debug_loc entry for the instruction range starting at MI. +static DebugLocEntry::Value getDebugLocValue(const MachineInstr *MI) { + const MDNode *Var = MI->getDebugVariable(); + + assert(MI->getNumOperands() == 3); + if (MI->getOperand(0).isReg()) { + MachineLocation MLoc; + // If the second operand is an immediate, this is a + // register-indirect address. + if (!MI->getOperand(1).isImm()) + MLoc.set(MI->getOperand(0).getReg()); + else + MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm()); + return DebugLocEntry::Value(Var, MLoc); + } + if (MI->getOperand(0).isImm()) + return DebugLocEntry::Value(Var, MI->getOperand(0).getImm()); + if (MI->getOperand(0).isFPImm()) + return DebugLocEntry::Value(Var, MI->getOperand(0).getFPImm()); + if (MI->getOperand(0).isCImm()) + return DebugLocEntry::Value(Var, MI->getOperand(0).getCImm()); + + llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!"); +} + +// Find variables for each lexical scope. +void +DwarfDebug::collectVariableInfo(SmallPtrSet<const MDNode *, 16> &Processed) { + LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); + DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode()); + + // Grab the variable info that was squirreled away in the MMI side-table. + collectVariableInfoFromMMITable(Processed); + + for (const auto &I : DbgValues) { + DIVariable DV(I.first); + if (Processed.count(DV)) + continue; + + // Instruction ranges, specifying where DV is accessible. + const auto &Ranges = I.second; + if (Ranges.empty()) + continue; + + LexicalScope *Scope = nullptr; + if (DV.getTag() == dwarf::DW_TAG_arg_variable && + DISubprogram(DV.getContext()).describes(CurFn->getFunction())) + Scope = LScopes.getCurrentFunctionScope(); + else if (MDNode *IA = DV.getInlinedAt()) { + DebugLoc DL = DebugLoc::getFromDILocation(IA); + Scope = LScopes.findInlinedScope(DebugLoc::get( + DL.getLine(), DL.getCol(), DV.getContext(), IA)); + } else + Scope = LScopes.findLexicalScope(DV.getContext()); + // If variable scope is not found then skip this variable. + if (!Scope) + continue; + + Processed.insert(DV); + const MachineInstr *MInsn = Ranges.front().first; + assert(MInsn->isDebugValue() && "History must begin with debug value"); + ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode()); + ConcreteVariables.push_back(make_unique<DbgVariable>(MInsn, this)); + DbgVariable *RegVar = ConcreteVariables.back().get(); + addScopeVariable(Scope, RegVar); + + // Check if the first DBG_VALUE is valid for the rest of the function. + if (Ranges.size() == 1 && Ranges.front().second == nullptr) + continue; + + // Handle multiple DBG_VALUE instructions describing one variable. + RegVar->setDotDebugLocOffset(DotDebugLocEntries.size()); + + DotDebugLocEntries.resize(DotDebugLocEntries.size() + 1); + DebugLocList &LocList = DotDebugLocEntries.back(); + LocList.Label = + Asm->GetTempSymbol("debug_loc", DotDebugLocEntries.size() - 1); + SmallVector<DebugLocEntry, 4> &DebugLoc = LocList.List; + for (auto I = Ranges.begin(), E = Ranges.end(); I != E; ++I) { + const MachineInstr *Begin = I->first; + const MachineInstr *End = I->second; + assert(Begin->isDebugValue() && "Invalid History entry"); + + // Check if a variable is unaccessible in this range. + if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() && + !Begin->getOperand(0).getReg()) + continue; + DEBUG(dbgs() << "DotDebugLoc Pair:\n" << "\t" << *Begin); + if (End != nullptr) + DEBUG(dbgs() << "\t" << *End); + else + DEBUG(dbgs() << "\tNULL\n"); + + const MCSymbol *StartLabel = getLabelBeforeInsn(Begin); + assert(StartLabel && "Forgot label before DBG_VALUE starting a range!"); + + const MCSymbol *EndLabel; + if (End != nullptr) + EndLabel = getLabelAfterInsn(End); + else if (std::next(I) == Ranges.end()) + EndLabel = FunctionEndSym; + else + EndLabel = getLabelBeforeInsn(std::next(I)->first); + assert(EndLabel && "Forgot label after instruction ending a range!"); + + DebugLocEntry Loc(StartLabel, EndLabel, getDebugLocValue(Begin), TheCU); + if (DebugLoc.empty() || !DebugLoc.back().Merge(Loc)) + DebugLoc.push_back(std::move(Loc)); + } + } + + // Collect info for variables that were optimized out. + DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables(); + for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) { + DIVariable DV(Variables.getElement(i)); + assert(DV.isVariable()); + if (!Processed.insert(DV)) + continue; + if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext())) { + ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode()); + ConcreteVariables.push_back(make_unique<DbgVariable>(DV, this)); + addScopeVariable(Scope, ConcreteVariables.back().get()); + } + } +} + +// Return Label preceding the instruction. +MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) { + MCSymbol *Label = LabelsBeforeInsn.lookup(MI); + assert(Label && "Didn't insert label before instruction"); + return Label; +} + +// Return Label immediately following the instruction. +MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) { + return LabelsAfterInsn.lookup(MI); +} + +// Process beginning of an instruction. +void DwarfDebug::beginInstruction(const MachineInstr *MI) { + assert(CurMI == nullptr); + CurMI = MI; + // Check if source location changes, but ignore DBG_VALUE locations. + if (!MI->isDebugValue()) { + DebugLoc DL = MI->getDebugLoc(); + if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) { + unsigned Flags = 0; + PrevInstLoc = DL; + if (DL == PrologEndLoc) { + Flags |= DWARF2_FLAG_PROLOGUE_END; + PrologEndLoc = DebugLoc(); + } + if (PrologEndLoc.isUnknown()) + Flags |= DWARF2_FLAG_IS_STMT; + + if (!DL.isUnknown()) { + const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext()); + recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags); + } else + recordSourceLine(0, 0, nullptr, 0); + } + } + + // Insert labels where requested. + DenseMap<const MachineInstr *, MCSymbol *>::iterator I = + LabelsBeforeInsn.find(MI); + + // No label needed. + if (I == LabelsBeforeInsn.end()) + return; + + // Label already assigned. + if (I->second) + return; + + if (!PrevLabel) { + PrevLabel = MMI->getContext().CreateTempSymbol(); + Asm->OutStreamer.EmitLabel(PrevLabel); + } + I->second = PrevLabel; +} + +// Process end of an instruction. +void DwarfDebug::endInstruction() { + assert(CurMI != nullptr); + // Don't create a new label after DBG_VALUE instructions. + // They don't generate code. + if (!CurMI->isDebugValue()) + PrevLabel = nullptr; + + DenseMap<const MachineInstr *, MCSymbol *>::iterator I = + LabelsAfterInsn.find(CurMI); + CurMI = nullptr; + + // No label needed. + if (I == LabelsAfterInsn.end()) + return; + + // Label already assigned. + if (I->second) + return; + + // We need a label after this instruction. + if (!PrevLabel) { + PrevLabel = MMI->getContext().CreateTempSymbol(); + Asm->OutStreamer.EmitLabel(PrevLabel); + } + I->second = PrevLabel; +} + +// Each LexicalScope has first instruction and last instruction to mark +// beginning and end of a scope respectively. Create an inverse map that list +// scopes starts (and ends) with an instruction. One instruction may start (or +// end) multiple scopes. Ignore scopes that are not reachable. +void DwarfDebug::identifyScopeMarkers() { + SmallVector<LexicalScope *, 4> WorkList; + WorkList.push_back(LScopes.getCurrentFunctionScope()); + while (!WorkList.empty()) { + LexicalScope *S = WorkList.pop_back_val(); + + const SmallVectorImpl<LexicalScope *> &Children = S->getChildren(); + if (!Children.empty()) + WorkList.append(Children.begin(), Children.end()); + + if (S->isAbstractScope()) + continue; + + for (const InsnRange &R : S->getRanges()) { + assert(R.first && "InsnRange does not have first instruction!"); + assert(R.second && "InsnRange does not have second instruction!"); + requestLabelBeforeInsn(R.first); + requestLabelAfterInsn(R.second); + } + } +} + +static DebugLoc findPrologueEndLoc(const MachineFunction *MF) { + // First known non-DBG_VALUE and non-frame setup location marks + // the beginning of the function body. + for (const auto &MBB : *MF) + for (const auto &MI : MBB) + if (!MI.isDebugValue() && !MI.getFlag(MachineInstr::FrameSetup) && + !MI.getDebugLoc().isUnknown()) + return MI.getDebugLoc(); + return DebugLoc(); +} + +// Gather pre-function debug information. Assumes being called immediately +// after the function entry point has been emitted. +void DwarfDebug::beginFunction(const MachineFunction *MF) { + CurFn = MF; + + // If there's no debug info for the function we're not going to do anything. + if (!MMI->hasDebugInfo()) + return; + + // Grab the lexical scopes for the function, if we don't have any of those + // then we're not going to be able to do anything. + LScopes.initialize(*MF); + if (LScopes.empty()) + return; + + assert(DbgValues.empty() && "DbgValues map wasn't cleaned!"); + + // Make sure that each lexical scope will have a begin/end label. + identifyScopeMarkers(); + + // Set DwarfDwarfCompileUnitID in MCContext to the Compile Unit this function + // belongs to so that we add to the correct per-cu line table in the + // non-asm case. + LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); + DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode()); + assert(TheCU && "Unable to find compile unit!"); + if (Asm->OutStreamer.hasRawTextSupport()) + // Use a single line table if we are generating assembly. + Asm->OutStreamer.getContext().setDwarfCompileUnitID(0); + else + Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID()); + + // Emit a label for the function so that we have a beginning address. + FunctionBeginSym = Asm->GetTempSymbol("func_begin", Asm->getFunctionNumber()); + // Assumes in correct section after the entry point. + Asm->OutStreamer.EmitLabel(FunctionBeginSym); + + // Calculate history for local variables. + calculateDbgValueHistory(MF, Asm->TM.getRegisterInfo(), DbgValues); + + // Request labels for the full history. + for (const auto &I : DbgValues) { + const auto &Ranges = I.second; + if (Ranges.empty()) + continue; + + // The first mention of a function argument gets the FunctionBeginSym + // label, so arguments are visible when breaking at function entry. + DIVariable DV(I.first); + if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable && + getDISubprogram(DV.getContext()).describes(MF->getFunction())) + LabelsBeforeInsn[Ranges.front().first] = FunctionBeginSym; + + for (const auto &Range : Ranges) { + requestLabelBeforeInsn(Range.first); + if (Range.second) + requestLabelAfterInsn(Range.second); + } + } + + PrevInstLoc = DebugLoc(); + PrevLabel = FunctionBeginSym; + + // Record beginning of function. + PrologEndLoc = findPrologueEndLoc(MF); + if (!PrologEndLoc.isUnknown()) { + DebugLoc FnStartDL = + PrologEndLoc.getFnDebugLoc(MF->getFunction()->getContext()); + recordSourceLine( + FnStartDL.getLine(), FnStartDL.getCol(), + FnStartDL.getScope(MF->getFunction()->getContext()), + // We'd like to list the prologue as "not statements" but GDB behaves + // poorly if we do that. Revisit this with caution/GDB (7.5+) testing. + DWARF2_FLAG_IS_STMT); + } +} + +void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) { + if (addCurrentFnArgument(Var, LS)) + return; + SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS]; + DIVariable DV = Var->getVariable(); + // Variables with positive arg numbers are parameters. + if (unsigned ArgNum = DV.getArgNumber()) { + // Keep all parameters in order at the start of the variable list to ensure + // function types are correct (no out-of-order parameters) + // + // This could be improved by only doing it for optimized builds (unoptimized + // builds have the right order to begin with), searching from the back (this + // would catch the unoptimized case quickly), or doing a binary search + // rather than linear search. + SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin(); + while (I != Vars.end()) { + unsigned CurNum = (*I)->getVariable().getArgNumber(); + // A local (non-parameter) variable has been found, insert immediately + // before it. + if (CurNum == 0) + break; + // A later indexed parameter has been found, insert immediately before it. + if (CurNum > ArgNum) + break; + ++I; + } + Vars.insert(I, Var); + return; + } + + Vars.push_back(Var); +} + +// Gather and emit post-function debug information. +void DwarfDebug::endFunction(const MachineFunction *MF) { + // Every beginFunction(MF) call should be followed by an endFunction(MF) call, + // though the beginFunction may not be called at all. + // We should handle both cases. + if (!CurFn) + CurFn = MF; + else + assert(CurFn == MF); + assert(CurFn != nullptr); + + if (!MMI->hasDebugInfo() || LScopes.empty()) { + // If we don't have a lexical scope for this function then there will + // be a hole in the range information. Keep note of this by setting the + // previously used section to nullptr. + PrevSection = nullptr; + PrevCU = nullptr; + CurFn = nullptr; + return; + } + + // Define end label for subprogram. + FunctionEndSym = Asm->GetTempSymbol("func_end", Asm->getFunctionNumber()); + // Assumes in correct section after the entry point. + Asm->OutStreamer.EmitLabel(FunctionEndSym); + + // Set DwarfDwarfCompileUnitID in MCContext to default value. + Asm->OutStreamer.getContext().setDwarfCompileUnitID(0); + + SmallPtrSet<const MDNode *, 16> ProcessedVars; + collectVariableInfo(ProcessedVars); + + LexicalScope *FnScope = LScopes.getCurrentFunctionScope(); + DwarfCompileUnit &TheCU = *SPMap.lookup(FnScope->getScopeNode()); + + // Construct abstract scopes. + for (LexicalScope *AScope : LScopes.getAbstractScopesList()) { + DISubprogram SP(AScope->getScopeNode()); + assert(SP.isSubprogram()); + // Collect info for variables that were optimized out. + DIArray Variables = SP.getVariables(); + for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) { + DIVariable DV(Variables.getElement(i)); + assert(DV && DV.isVariable()); + if (!ProcessedVars.insert(DV)) + continue; + ensureAbstractVariableIsCreated(DV, DV.getContext()); + } + constructAbstractSubprogramScopeDIE(TheCU, AScope); + } + + DIE &CurFnDIE = constructSubprogramScopeDIE(TheCU, FnScope); + if (!CurFn->getTarget().Options.DisableFramePointerElim(*CurFn)) + TheCU.addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr); + + // Add the range of this function to the list of ranges for the CU. + RangeSpan Span(FunctionBeginSym, FunctionEndSym); + TheCU.addRange(std::move(Span)); + PrevSection = Asm->getCurrentSection(); + PrevCU = &TheCU; + + // Clear debug info + // Ownership of DbgVariables is a bit subtle - ScopeVariables owns all the + // DbgVariables except those that are also in AbstractVariables (since they + // can be used cross-function) + ScopeVariables.clear(); + CurrentFnArguments.clear(); + DbgValues.clear(); + LabelsBeforeInsn.clear(); + LabelsAfterInsn.clear(); + PrevLabel = nullptr; + CurFn = nullptr; +} + +// Register a source line with debug info. Returns the unique label that was +// emitted and which provides correspondence to the source line list. +void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S, + unsigned Flags) { + StringRef Fn; + StringRef Dir; + unsigned Src = 1; + unsigned Discriminator = 0; + if (DIScope Scope = DIScope(S)) { + assert(Scope.isScope()); + Fn = Scope.getFilename(); + Dir = Scope.getDirectory(); + if (Scope.isLexicalBlock()) + Discriminator = DILexicalBlock(S).getDiscriminator(); + + unsigned CUID = Asm->OutStreamer.getContext().getDwarfCompileUnitID(); + Src = static_cast<DwarfCompileUnit &>(*InfoHolder.getUnits()[CUID]) + .getOrCreateSourceID(Fn, Dir); + } + Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0, + Discriminator, Fn); +} + +//===----------------------------------------------------------------------===// +// Emit Methods +//===----------------------------------------------------------------------===// + +// Emit initial Dwarf sections with a label at the start of each one. +void DwarfDebug::emitSectionLabels() { + const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); + + // Dwarf sections base addresses. + DwarfInfoSectionSym = + emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info"); + if (useSplitDwarf()) + DwarfInfoDWOSectionSym = + emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo"); + DwarfAbbrevSectionSym = + emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev"); + if (useSplitDwarf()) + DwarfAbbrevDWOSectionSym = emitSectionSym( + Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo"); + if (GenerateARangeSection) + emitSectionSym(Asm, TLOF.getDwarfARangesSection()); + + DwarfLineSectionSym = + emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line"); + if (GenerateGnuPubSections) { + DwarfGnuPubNamesSectionSym = + emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection()); + DwarfGnuPubTypesSectionSym = + emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection()); + } else if (HasDwarfPubSections) { + emitSectionSym(Asm, TLOF.getDwarfPubNamesSection()); + emitSectionSym(Asm, TLOF.getDwarfPubTypesSection()); + } + + DwarfStrSectionSym = + emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string"); + if (useSplitDwarf()) { + DwarfStrDWOSectionSym = + emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string"); + DwarfAddrSectionSym = + emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec"); + DwarfDebugLocSectionSym = + emitSectionSym(Asm, TLOF.getDwarfLocDWOSection(), "skel_loc"); + } else + DwarfDebugLocSectionSym = + emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc"); + DwarfDebugRangeSectionSym = + emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range"); +} + +// Recursively emits a debug information entry. +void DwarfDebug::emitDIE(DIE &Die) { + // Get the abbreviation for this DIE. + const DIEAbbrev &Abbrev = Die.getAbbrev(); + + // Emit the code (index) for the abbreviation. + if (Asm->isVerbose()) + Asm->OutStreamer.AddComment("Abbrev [" + Twine(Abbrev.getNumber()) + + "] 0x" + Twine::utohexstr(Die.getOffset()) + + ":0x" + Twine::utohexstr(Die.getSize()) + " " + + dwarf::TagString(Abbrev.getTag())); + Asm->EmitULEB128(Abbrev.getNumber()); + + const SmallVectorImpl<DIEValue *> &Values = Die.getValues(); + const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData(); + + // Emit the DIE attribute values. + for (unsigned i = 0, N = Values.size(); i < N; ++i) { + dwarf::Attribute Attr = AbbrevData[i].getAttribute(); + dwarf::Form Form = AbbrevData[i].getForm(); + assert(Form && "Too many attributes for DIE (check abbreviation)"); + + if (Asm->isVerbose()) { + Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr)); + if (Attr == dwarf::DW_AT_accessibility) + Asm->OutStreamer.AddComment(dwarf::AccessibilityString( + cast<DIEInteger>(Values[i])->getValue())); + } + + // Emit an attribute using the defined form. + Values[i]->EmitValue(Asm, Form); + } + + // Emit the DIE children if any. + if (Abbrev.hasChildren()) { + for (auto &Child : Die.getChildren()) + emitDIE(*Child); + + Asm->OutStreamer.AddComment("End Of Children Mark"); + Asm->EmitInt8(0); + } +} + +// Emit the debug info section. +void DwarfDebug::emitDebugInfo() { + DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; + + Holder.emitUnits(this, DwarfAbbrevSectionSym); +} + +// Emit the abbreviation section. +void DwarfDebug::emitAbbreviations() { + DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; + + Holder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection()); +} + +// Emit the last address of the section and the end of the line matrix. +void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) { + // Define last address of section. + Asm->OutStreamer.AddComment("Extended Op"); + Asm->EmitInt8(0); + + Asm->OutStreamer.AddComment("Op size"); + Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1); + Asm->OutStreamer.AddComment("DW_LNE_set_address"); + Asm->EmitInt8(dwarf::DW_LNE_set_address); + + Asm->OutStreamer.AddComment("Section end label"); + + Asm->OutStreamer.EmitSymbolValue( + Asm->GetTempSymbol("section_end", SectionEnd), + Asm->getDataLayout().getPointerSize()); + + // Mark end of matrix. + Asm->OutStreamer.AddComment("DW_LNE_end_sequence"); + Asm->EmitInt8(0); + Asm->EmitInt8(1); + Asm->EmitInt8(1); +} + +// Emit visible names into a hashed accelerator table section. +void DwarfDebug::emitAccelNames() { + AccelNames.FinalizeTable(Asm, "Names"); + Asm->OutStreamer.SwitchSection( + Asm->getObjFileLowering().getDwarfAccelNamesSection()); + MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin"); + Asm->OutStreamer.EmitLabel(SectionBegin); + + // Emit the full data. + AccelNames.Emit(Asm, SectionBegin, &InfoHolder); +} + +// Emit objective C classes and categories into a hashed accelerator table +// section. +void DwarfDebug::emitAccelObjC() { + AccelObjC.FinalizeTable(Asm, "ObjC"); + Asm->OutStreamer.SwitchSection( + Asm->getObjFileLowering().getDwarfAccelObjCSection()); + MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin"); + Asm->OutStreamer.EmitLabel(SectionBegin); + + // Emit the full data. + AccelObjC.Emit(Asm, SectionBegin, &InfoHolder); +} + +// Emit namespace dies into a hashed accelerator table. +void DwarfDebug::emitAccelNamespaces() { + AccelNamespace.FinalizeTable(Asm, "namespac"); + Asm->OutStreamer.SwitchSection( + Asm->getObjFileLowering().getDwarfAccelNamespaceSection()); + MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin"); + Asm->OutStreamer.EmitLabel(SectionBegin); + + // Emit the full data. + AccelNamespace.Emit(Asm, SectionBegin, &InfoHolder); +} + +// Emit type dies into a hashed accelerator table. +void DwarfDebug::emitAccelTypes() { + + AccelTypes.FinalizeTable(Asm, "types"); + Asm->OutStreamer.SwitchSection( + Asm->getObjFileLowering().getDwarfAccelTypesSection()); + MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin"); + Asm->OutStreamer.EmitLabel(SectionBegin); + + // Emit the full data. + AccelTypes.Emit(Asm, SectionBegin, &InfoHolder); +} + +// Public name handling. +// The format for the various pubnames: +// +// dwarf pubnames - offset/name pairs where the offset is the offset into the CU +// for the DIE that is named. +// +// gnu pubnames - offset/index value/name tuples where the offset is the offset +// into the CU and the index value is computed according to the type of value +// for the DIE that is named. +// +// For type units the offset is the offset of the skeleton DIE. For split dwarf +// it's the offset within the debug_info/debug_types dwo section, however, the +// reference in the pubname header doesn't change. + +/// computeIndexValue - Compute the gdb index value for the DIE and CU. +static dwarf::PubIndexEntryDescriptor computeIndexValue(DwarfUnit *CU, + const DIE *Die) { + dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC; + + // We could have a specification DIE that has our most of our knowledge, + // look for that now. + DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification); + if (SpecVal) { + DIE &SpecDIE = cast<DIEEntry>(SpecVal)->getEntry(); + if (SpecDIE.findAttribute(dwarf::DW_AT_external)) + Linkage = dwarf::GIEL_EXTERNAL; + } else if (Die->findAttribute(dwarf::DW_AT_external)) + Linkage = dwarf::GIEL_EXTERNAL; + + switch (Die->getTag()) { + case dwarf::DW_TAG_class_type: + case dwarf::DW_TAG_structure_type: + case dwarf::DW_TAG_union_type: + case dwarf::DW_TAG_enumeration_type: + return dwarf::PubIndexEntryDescriptor( + dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus + ? dwarf::GIEL_STATIC + : dwarf::GIEL_EXTERNAL); + case dwarf::DW_TAG_typedef: + case dwarf::DW_TAG_base_type: + case dwarf::DW_TAG_subrange_type: + return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC); + case dwarf::DW_TAG_namespace: + return dwarf::GIEK_TYPE; + case dwarf::DW_TAG_subprogram: + return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage); + case dwarf::DW_TAG_constant: + case dwarf::DW_TAG_variable: + return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage); + case dwarf::DW_TAG_enumerator: + return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, + dwarf::GIEL_STATIC); + default: + return dwarf::GIEK_NONE; + } +} + +/// emitDebugPubNames - Emit visible names into a debug pubnames section. +/// +void DwarfDebug::emitDebugPubNames(bool GnuStyle) { + const MCSection *PSec = + GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection() + : Asm->getObjFileLowering().getDwarfPubNamesSection(); + + emitDebugPubSection(GnuStyle, PSec, "Names", &DwarfUnit::getGlobalNames); +} + +void DwarfDebug::emitDebugPubSection( + bool GnuStyle, const MCSection *PSec, StringRef Name, + const StringMap<const DIE *> &(DwarfUnit::*Accessor)() const) { + for (const auto &NU : CUMap) { + DwarfCompileUnit *TheU = NU.second; + + const auto &Globals = (TheU->*Accessor)(); + + if (Globals.empty()) + continue; + + if (auto Skeleton = static_cast<DwarfCompileUnit *>(TheU->getSkeleton())) + TheU = Skeleton; + unsigned ID = TheU->getUniqueID(); + + // Start the dwarf pubnames section. + Asm->OutStreamer.SwitchSection(PSec); + + // Emit the header. + Asm->OutStreamer.AddComment("Length of Public " + Name + " Info"); + MCSymbol *BeginLabel = Asm->GetTempSymbol("pub" + Name + "_begin", ID); + MCSymbol *EndLabel = Asm->GetTempSymbol("pub" + Name + "_end", ID); + Asm->EmitLabelDifference(EndLabel, BeginLabel, 4); + + Asm->OutStreamer.EmitLabel(BeginLabel); + + Asm->OutStreamer.AddComment("DWARF Version"); + Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION); + + Asm->OutStreamer.AddComment("Offset of Compilation Unit Info"); + Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym()); + + Asm->OutStreamer.AddComment("Compilation Unit Length"); + Asm->EmitLabelDifference(TheU->getLabelEnd(), TheU->getLabelBegin(), 4); + + // Emit the pubnames for this compilation unit. + for (const auto &GI : Globals) { + const char *Name = GI.getKeyData(); + const DIE *Entity = GI.second; + + Asm->OutStreamer.AddComment("DIE offset"); + Asm->EmitInt32(Entity->getOffset()); + + if (GnuStyle) { + dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity); + Asm->OutStreamer.AddComment( + Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " + + dwarf::GDBIndexEntryLinkageString(Desc.Linkage)); + Asm->EmitInt8(Desc.toBits()); + } + + Asm->OutStreamer.AddComment("External Name"); + Asm->OutStreamer.EmitBytes(StringRef(Name, GI.getKeyLength() + 1)); + } + + Asm->OutStreamer.AddComment("End Mark"); + Asm->EmitInt32(0); + Asm->OutStreamer.EmitLabel(EndLabel); + } +} + +void DwarfDebug::emitDebugPubTypes(bool GnuStyle) { + const MCSection *PSec = + GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection() + : Asm->getObjFileLowering().getDwarfPubTypesSection(); + + emitDebugPubSection(GnuStyle, PSec, "Types", &DwarfUnit::getGlobalTypes); +} + +// Emit visible names into a debug str section. +void DwarfDebug::emitDebugStr() { + DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder; + Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection()); +} + +void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer, + const DebugLocEntry &Entry) { + assert(Entry.getValues().size() == 1 && + "multi-value entries are not supported yet."); + const DebugLocEntry::Value Value = Entry.getValues()[0]; + DIVariable DV(Value.getVariable()); + if (Value.isInt()) { + DIBasicType BTy(resolve(DV.getType())); + if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed || + BTy.getEncoding() == dwarf::DW_ATE_signed_char)) { + Streamer.EmitInt8(dwarf::DW_OP_consts, "DW_OP_consts"); + Streamer.EmitSLEB128(Value.getInt()); + } else { + Streamer.EmitInt8(dwarf::DW_OP_constu, "DW_OP_constu"); + Streamer.EmitULEB128(Value.getInt()); + } + } else if (Value.isLocation()) { + MachineLocation Loc = Value.getLoc(); + if (!DV.hasComplexAddress()) + // Regular entry. + Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect()); + else { + // Complex address entry. + unsigned N = DV.getNumAddrElements(); + unsigned i = 0; + if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) { + if (Loc.getOffset()) { + i = 2; + Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect()); + Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref"); + Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst"); + Streamer.EmitSLEB128(DV.getAddrElement(1)); + } else { + // If first address element is OpPlus then emit + // DW_OP_breg + Offset instead of DW_OP_reg + Offset. + MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1)); + Asm->EmitDwarfRegOp(Streamer, TLoc, DV.isIndirect()); + i = 2; + } + } else { + Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect()); + } + + // Emit remaining complex address elements. + for (; i < N; ++i) { + uint64_t Element = DV.getAddrElement(i); + if (Element == DIBuilder::OpPlus) { + Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst"); + Streamer.EmitULEB128(DV.getAddrElement(++i)); + } else if (Element == DIBuilder::OpDeref) { + if (!Loc.isReg()) + Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref"); + } else + llvm_unreachable("unknown Opcode found in complex address"); + } + } + } + // else ... ignore constant fp. There is not any good way to + // to represent them here in dwarf. + // FIXME: ^ +} + +void DwarfDebug::emitDebugLocEntryLocation(const DebugLocEntry &Entry) { + Asm->OutStreamer.AddComment("Loc expr size"); + MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol(); + MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol(); + Asm->EmitLabelDifference(end, begin, 2); + Asm->OutStreamer.EmitLabel(begin); + // Emit the entry. + APByteStreamer Streamer(*Asm); + emitDebugLocEntry(Streamer, Entry); + // Close the range. + Asm->OutStreamer.EmitLabel(end); +} + +// Emit locations into the debug loc section. +void DwarfDebug::emitDebugLoc() { + // Start the dwarf loc section. + Asm->OutStreamer.SwitchSection( + Asm->getObjFileLowering().getDwarfLocSection()); + unsigned char Size = Asm->getDataLayout().getPointerSize(); + for (const auto &DebugLoc : DotDebugLocEntries) { + Asm->OutStreamer.EmitLabel(DebugLoc.Label); + for (const auto &Entry : DebugLoc.List) { + // Set up the range. This range is relative to the entry point of the + // compile unit. This is a hard coded 0 for low_pc when we're emitting + // ranges, or the DW_AT_low_pc on the compile unit otherwise. + const DwarfCompileUnit *CU = Entry.getCU(); + if (CU->getRanges().size() == 1) { + // Grab the begin symbol from the first range as our base. + const MCSymbol *Base = CU->getRanges()[0].getStart(); + Asm->EmitLabelDifference(Entry.getBeginSym(), Base, Size); + Asm->EmitLabelDifference(Entry.getEndSym(), Base, Size); + } else { + Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size); + Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size); + } + + emitDebugLocEntryLocation(Entry); + } + Asm->OutStreamer.EmitIntValue(0, Size); + Asm->OutStreamer.EmitIntValue(0, Size); + } +} + +void DwarfDebug::emitDebugLocDWO() { + Asm->OutStreamer.SwitchSection( + Asm->getObjFileLowering().getDwarfLocDWOSection()); + for (const auto &DebugLoc : DotDebugLocEntries) { + Asm->OutStreamer.EmitLabel(DebugLoc.Label); + for (const auto &Entry : DebugLoc.List) { + // Just always use start_length for now - at least that's one address + // rather than two. We could get fancier and try to, say, reuse an + // address we know we've emitted elsewhere (the start of the function? + // The start of the CU or CU subrange that encloses this range?) + Asm->EmitInt8(dwarf::DW_LLE_start_length_entry); + unsigned idx = AddrPool.getIndex(Entry.getBeginSym()); + Asm->EmitULEB128(idx); + Asm->EmitLabelDifference(Entry.getEndSym(), Entry.getBeginSym(), 4); + + emitDebugLocEntryLocation(Entry); + } + Asm->EmitInt8(dwarf::DW_LLE_end_of_list_entry); + } +} + +struct ArangeSpan { + const MCSymbol *Start, *End; +}; + +// Emit a debug aranges section, containing a CU lookup for any +// address we can tie back to a CU. +void DwarfDebug::emitDebugARanges() { + // Start the dwarf aranges section. + Asm->OutStreamer.SwitchSection( + Asm->getObjFileLowering().getDwarfARangesSection()); + + typedef DenseMap<DwarfCompileUnit *, std::vector<ArangeSpan>> SpansType; + + SpansType Spans; + + // Build a list of sections used. + std::vector<const MCSection *> Sections; + for (const auto &it : SectionMap) { + const MCSection *Section = it.first; + Sections.push_back(Section); + } + + // Sort the sections into order. + // This is only done to ensure consistent output order across different runs. + std::sort(Sections.begin(), Sections.end(), SectionSort); + + // Build a set of address spans, sorted by CU. + for (const MCSection *Section : Sections) { + SmallVector<SymbolCU, 8> &List = SectionMap[Section]; + if (List.size() < 2) + continue; + + // Sort the symbols by offset within the section. + std::sort(List.begin(), List.end(), + [&](const SymbolCU &A, const SymbolCU &B) { + unsigned IA = A.Sym ? Asm->OutStreamer.GetSymbolOrder(A.Sym) : 0; + unsigned IB = B.Sym ? Asm->OutStreamer.GetSymbolOrder(B.Sym) : 0; + + // Symbols with no order assigned should be placed at the end. + // (e.g. section end labels) + if (IA == 0) + return false; + if (IB == 0) + return true; + return IA < IB; + }); + + // If we have no section (e.g. common), just write out + // individual spans for each symbol. + if (!Section) { + for (const SymbolCU &Cur : List) { + ArangeSpan Span; + Span.Start = Cur.Sym; + Span.End = nullptr; + if (Cur.CU) + Spans[Cur.CU].push_back(Span); + } + } else { + // Build spans between each label. + const MCSymbol *StartSym = List[0].Sym; + for (size_t n = 1, e = List.size(); n < e; n++) { + const SymbolCU &Prev = List[n - 1]; + const SymbolCU &Cur = List[n]; + + // Try and build the longest span we can within the same CU. + if (Cur.CU != Prev.CU) { + ArangeSpan Span; + Span.Start = StartSym; + Span.End = Cur.Sym; + Spans[Prev.CU].push_back(Span); + StartSym = Cur.Sym; + } + } + } + } + + unsigned PtrSize = Asm->getDataLayout().getPointerSize(); + + // Build a list of CUs used. + std::vector<DwarfCompileUnit *> CUs; + for (const auto &it : Spans) { + DwarfCompileUnit *CU = it.first; + CUs.push_back(CU); + } + + // Sort the CU list (again, to ensure consistent output order). + std::sort(CUs.begin(), CUs.end(), [](const DwarfUnit *A, const DwarfUnit *B) { + return A->getUniqueID() < B->getUniqueID(); + }); + + // Emit an arange table for each CU we used. + for (DwarfCompileUnit *CU : CUs) { + std::vector<ArangeSpan> &List = Spans[CU]; + + // Emit size of content not including length itself. + unsigned ContentSize = + sizeof(int16_t) + // DWARF ARange version number + sizeof(int32_t) + // Offset of CU in the .debug_info section + sizeof(int8_t) + // Pointer Size (in bytes) + sizeof(int8_t); // Segment Size (in bytes) + + unsigned TupleSize = PtrSize * 2; + + // 7.20 in the Dwarf specs requires the table to be aligned to a tuple. + unsigned Padding = + OffsetToAlignment(sizeof(int32_t) + ContentSize, TupleSize); + + ContentSize += Padding; + ContentSize += (List.size() + 1) * TupleSize; + + // For each compile unit, write the list of spans it covers. + Asm->OutStreamer.AddComment("Length of ARange Set"); + Asm->EmitInt32(ContentSize); + Asm->OutStreamer.AddComment("DWARF Arange version number"); + Asm->EmitInt16(dwarf::DW_ARANGES_VERSION); + Asm->OutStreamer.AddComment("Offset Into Debug Info Section"); + Asm->EmitSectionOffset(CU->getLocalLabelBegin(), CU->getLocalSectionSym()); + Asm->OutStreamer.AddComment("Address Size (in bytes)"); + Asm->EmitInt8(PtrSize); + Asm->OutStreamer.AddComment("Segment Size (in bytes)"); + Asm->EmitInt8(0); + + Asm->OutStreamer.EmitFill(Padding, 0xff); + + for (const ArangeSpan &Span : List) { + Asm->EmitLabelReference(Span.Start, PtrSize); + + // Calculate the size as being from the span start to it's end. + if (Span.End) { + Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize); + } else { + // For symbols without an end marker (e.g. common), we + // write a single arange entry containing just that one symbol. + uint64_t Size = SymSize[Span.Start]; + if (Size == 0) + Size = 1; + + Asm->OutStreamer.EmitIntValue(Size, PtrSize); + } + } + + Asm->OutStreamer.AddComment("ARange terminator"); + Asm->OutStreamer.EmitIntValue(0, PtrSize); + Asm->OutStreamer.EmitIntValue(0, PtrSize); + } +} + +// Emit visible names into a debug ranges section. +void DwarfDebug::emitDebugRanges() { + // Start the dwarf ranges section. + Asm->OutStreamer.SwitchSection( + Asm->getObjFileLowering().getDwarfRangesSection()); + + // Size for our labels. + unsigned char Size = Asm->getDataLayout().getPointerSize(); + + // Grab the specific ranges for the compile units in the module. + for (const auto &I : CUMap) { + DwarfCompileUnit *TheCU = I.second; + + // Iterate over the misc ranges for the compile units in the module. + for (const RangeSpanList &List : TheCU->getRangeLists()) { + // Emit our symbol so we can find the beginning of the range. + Asm->OutStreamer.EmitLabel(List.getSym()); + + for (const RangeSpan &Range : List.getRanges()) { + const MCSymbol *Begin = Range.getStart(); + const MCSymbol *End = Range.getEnd(); + assert(Begin && "Range without a begin symbol?"); + assert(End && "Range without an end symbol?"); + if (TheCU->getRanges().size() == 1) { + // Grab the begin symbol from the first range as our base. + const MCSymbol *Base = TheCU->getRanges()[0].getStart(); + Asm->EmitLabelDifference(Begin, Base, Size); + Asm->EmitLabelDifference(End, Base, Size); + } else { + Asm->OutStreamer.EmitSymbolValue(Begin, Size); + Asm->OutStreamer.EmitSymbolValue(End, Size); + } + } + + // And terminate the list with two 0 values. + Asm->OutStreamer.EmitIntValue(0, Size); + Asm->OutStreamer.EmitIntValue(0, Size); + } + + // Now emit a range for the CU itself. + if (TheCU->getRanges().size() > 1) { + Asm->OutStreamer.EmitLabel( + Asm->GetTempSymbol("cu_ranges", TheCU->getUniqueID())); + for (const RangeSpan &Range : TheCU->getRanges()) { + const MCSymbol *Begin = Range.getStart(); + const MCSymbol *End = Range.getEnd(); + assert(Begin && "Range without a begin symbol?"); + assert(End && "Range without an end symbol?"); + Asm->OutStreamer.EmitSymbolValue(Begin, Size); + Asm->OutStreamer.EmitSymbolValue(End, Size); + } + // And terminate the list with two 0 values. + Asm->OutStreamer.EmitIntValue(0, Size); + Asm->OutStreamer.EmitIntValue(0, Size); + } + } +} + +// DWARF5 Experimental Separate Dwarf emitters. + +void DwarfDebug::initSkeletonUnit(const DwarfUnit &U, DIE &Die, + std::unique_ptr<DwarfUnit> NewU) { + NewU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name, + U.getCUNode().getSplitDebugFilename()); + + if (!CompilationDir.empty()) + NewU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir); + + addGnuPubAttributes(*NewU, Die); + + SkeletonHolder.addUnit(std::move(NewU)); +} + +// This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list, +// DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id, +// DW_AT_addr_base, DW_AT_ranges_base. +DwarfCompileUnit &DwarfDebug::constructSkeletonCU(const DwarfCompileUnit &CU) { + + auto OwnedUnit = make_unique<DwarfCompileUnit>( + CU.getUniqueID(), CU.getCUNode(), Asm, this, &SkeletonHolder); + DwarfCompileUnit &NewCU = *OwnedUnit; + NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(), + DwarfInfoSectionSym); + + NewCU.initStmtList(DwarfLineSectionSym); + + initSkeletonUnit(CU, NewCU.getUnitDie(), std::move(OwnedUnit)); + + return NewCU; +} + +// This DIE has the following attributes: DW_AT_comp_dir, DW_AT_dwo_name, +// DW_AT_addr_base. +DwarfTypeUnit &DwarfDebug::constructSkeletonTU(DwarfTypeUnit &TU) { + DwarfCompileUnit &CU = static_cast<DwarfCompileUnit &>( + *SkeletonHolder.getUnits()[TU.getCU().getUniqueID()]); + + auto OwnedUnit = make_unique<DwarfTypeUnit>(TU.getUniqueID(), CU, Asm, this, + &SkeletonHolder); + DwarfTypeUnit &NewTU = *OwnedUnit; + NewTU.setTypeSignature(TU.getTypeSignature()); + NewTU.setType(nullptr); + NewTU.initSection( + Asm->getObjFileLowering().getDwarfTypesSection(TU.getTypeSignature())); + + initSkeletonUnit(TU, NewTU.getUnitDie(), std::move(OwnedUnit)); + return NewTU; +} + +// Emit the .debug_info.dwo section for separated dwarf. This contains the +// compile units that would normally be in debug_info. +void DwarfDebug::emitDebugInfoDWO() { + assert(useSplitDwarf() && "No split dwarf debug info?"); + // Don't pass an abbrev symbol, using a constant zero instead so as not to + // emit relocations into the dwo file. + InfoHolder.emitUnits(this, /* AbbrevSymbol */ nullptr); +} + +// Emit the .debug_abbrev.dwo section for separated dwarf. This contains the +// abbreviations for the .debug_info.dwo section. +void DwarfDebug::emitDebugAbbrevDWO() { + assert(useSplitDwarf() && "No split dwarf?"); + InfoHolder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection()); +} + +void DwarfDebug::emitDebugLineDWO() { + assert(useSplitDwarf() && "No split dwarf?"); + Asm->OutStreamer.SwitchSection( + Asm->getObjFileLowering().getDwarfLineDWOSection()); + SplitTypeUnitFileTable.Emit(Asm->OutStreamer); +} + +// Emit the .debug_str.dwo section for separated dwarf. This contains the +// string section and is identical in format to traditional .debug_str +// sections. +void DwarfDebug::emitDebugStrDWO() { + assert(useSplitDwarf() && "No split dwarf?"); + const MCSection *OffSec = + Asm->getObjFileLowering().getDwarfStrOffDWOSection(); + const MCSymbol *StrSym = DwarfStrSectionSym; + InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(), + OffSec, StrSym); +} + +MCDwarfDwoLineTable *DwarfDebug::getDwoLineTable(const DwarfCompileUnit &CU) { + if (!useSplitDwarf()) + return nullptr; + if (SingleCU) + SplitTypeUnitFileTable.setCompilationDir(CU.getCUNode().getDirectory()); + return &SplitTypeUnitFileTable; +} + +static uint64_t makeTypeSignature(StringRef Identifier) { + MD5 Hash; + Hash.update(Identifier); + // ... take the least significant 8 bytes and return those. Our MD5 + // implementation always returns its results in little endian, swap bytes + // appropriately. + MD5::MD5Result Result; + Hash.final(Result); + return *reinterpret_cast<support::ulittle64_t *>(Result + 8); +} + +void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU, + StringRef Identifier, DIE &RefDie, + DICompositeType CTy) { + // Fast path if we're building some type units and one has already used the + // address pool we know we're going to throw away all this work anyway, so + // don't bother building dependent types. + if (!TypeUnitsUnderConstruction.empty() && AddrPool.hasBeenUsed()) + return; + + const DwarfTypeUnit *&TU = DwarfTypeUnits[CTy]; + if (TU) { + CU.addDIETypeSignature(RefDie, *TU); + return; + } + + bool TopLevelType = TypeUnitsUnderConstruction.empty(); + AddrPool.resetUsedFlag(); + + auto OwnedUnit = + make_unique<DwarfTypeUnit>(InfoHolder.getUnits().size(), CU, Asm, this, + &InfoHolder, getDwoLineTable(CU)); + DwarfTypeUnit &NewTU = *OwnedUnit; + DIE &UnitDie = NewTU.getUnitDie(); + TU = &NewTU; + TypeUnitsUnderConstruction.push_back( + std::make_pair(std::move(OwnedUnit), CTy)); + + NewTU.addUInt(UnitDie, dwarf::DW_AT_language, dwarf::DW_FORM_data2, + CU.getLanguage()); + + uint64_t Signature = makeTypeSignature(Identifier); + NewTU.setTypeSignature(Signature); + + if (!useSplitDwarf()) + CU.applyStmtList(UnitDie); + + // FIXME: Skip using COMDAT groups for type units in the .dwo file once tools + // such as DWP ( http://gcc.gnu.org/wiki/DebugFissionDWP ) can cope with it. + NewTU.initSection( + useSplitDwarf() + ? Asm->getObjFileLowering().getDwarfTypesDWOSection(Signature) + : Asm->getObjFileLowering().getDwarfTypesSection(Signature)); + + NewTU.setType(NewTU.createTypeDIE(CTy)); + + if (TopLevelType) { + auto TypeUnitsToAdd = std::move(TypeUnitsUnderConstruction); + TypeUnitsUnderConstruction.clear(); + + // Types referencing entries in the address table cannot be placed in type + // units. + if (AddrPool.hasBeenUsed()) { + + // Remove all the types built while building this type. + // This is pessimistic as some of these types might not be dependent on + // the type that used an address. + for (const auto &TU : TypeUnitsToAdd) + DwarfTypeUnits.erase(TU.second); + + // Construct this type in the CU directly. + // This is inefficient because all the dependent types will be rebuilt + // from scratch, including building them in type units, discovering that + // they depend on addresses, throwing them out and rebuilding them. + CU.constructTypeDIE(RefDie, CTy); + return; + } + + // If the type wasn't dependent on fission addresses, finish adding the type + // and all its dependent types. + for (auto &TU : TypeUnitsToAdd) { + if (useSplitDwarf()) + TU.first->setSkeleton(constructSkeletonTU(*TU.first)); + InfoHolder.addUnit(std::move(TU.first)); + } + } + CU.addDIETypeSignature(RefDie, NewTU); +} + +void DwarfDebug::attachLowHighPC(DwarfCompileUnit &Unit, DIE &D, + MCSymbol *Begin, MCSymbol *End) { + assert(Begin && "Begin label should not be null!"); + assert(End && "End label should not be null!"); + assert(Begin->isDefined() && "Invalid starting label"); + assert(End->isDefined() && "Invalid end label"); + + Unit.addLabelAddress(D, dwarf::DW_AT_low_pc, Begin); + if (DwarfVersion < 4) + Unit.addLabelAddress(D, dwarf::DW_AT_high_pc, End); + else + Unit.addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin); +} + +// Accelerator table mutators - add each name along with its companion +// DIE to the proper table while ensuring that the name that we're going +// to reference is in the string table. We do this since the names we +// add may not only be identical to the names in the DIE. +void DwarfDebug::addAccelName(StringRef Name, const DIE &Die) { + if (!useDwarfAccelTables()) + return; + AccelNames.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name), + &Die); +} + +void DwarfDebug::addAccelObjC(StringRef Name, const DIE &Die) { + if (!useDwarfAccelTables()) + return; + AccelObjC.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name), + &Die); +} + +void DwarfDebug::addAccelNamespace(StringRef Name, const DIE &Die) { + if (!useDwarfAccelTables()) + return; + AccelNamespace.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name), + &Die); +} + +void DwarfDebug::addAccelType(StringRef Name, const DIE &Die, char Flags) { + if (!useDwarfAccelTables()) + return; + AccelTypes.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name), + &Die); +} |
