[llvm] a8c5a46 - [Dsymutil][Debuginfo][NFC] #4 Refactor dsymutil to separate DWARF optimizing part.
Alexey Lapshin via llvm-commits
llvm-commits at lists.llvm.org
Thu Jan 23 07:16:39 PST 2020
Author: Alexey Lapshin
Date: 2020-01-23T18:16:32+03:00
New Revision: a8c5a461a8e81684d28ca06eb2f65bf43a88e03b
URL: https://github.com/llvm/llvm-project/commit/a8c5a461a8e81684d28ca06eb2f65bf43a88e03b
DIFF: https://github.com/llvm/llvm-project/commit/a8c5a461a8e81684d28ca06eb2f65bf43a88e03b.diff
LOG: [Dsymutil][Debuginfo][NFC] #4 Refactor dsymutil to separate DWARF optimizing part.
Summary:
The primary goal of this refactoring is to separate DWARF optimizing part.
So that it could be reused by linker or by any other client.
There was a thread on llvm-dev discussing the necessity of such a refactoring:
http://lists.llvm.org/pipermail/llvm-dev/2019-September/135068.html.
This is a final part from series of patches for dsymutil.
Previous patches : D71068, D71839, D72476. This patch:
1. Creates lib/DWARFLinker interface :
void addObjectFile(DwarfLinkerObjFile &ObjFile);
bool link();
void setOptions;
1. Moves all linking logic from tools/dsymutil/DwarfLinkerForBinary
into lib/DWARFLinker.
2. Renames RelocationManager into AddressesManager.
3. Remarks creation logic moved from separate parallel execution
into object file loading routine.
Testing: it passes "check-all" lit testing. MD5 checksum for clang .dSYM bundle
matches for the dsymutil with/without that patch.
Reviewers: JDevlieghere, friss, dblaikie, aprantl, jdoerfert
Reviewed By: JDevlieghere
Subscribers: merge_guards_bot, hiraditya, jfb, llvm-commits, probinson, thegameg
Tags: #llvm, #debug-info
Differential Revision: https://reviews.llvm.org/D72915
Added:
Modified:
llvm/include/llvm/CodeGen/DIE.h
llvm/include/llvm/DWARFLinker/DWARFLinker.h
llvm/lib/DWARFLinker/DWARFLinker.cpp
llvm/tools/dsymutil/DwarfLinkerForBinary.cpp
llvm/tools/dsymutil/DwarfLinkerForBinary.h
llvm/tools/dsymutil/DwarfStreamer.cpp
llvm/tools/dsymutil/LinkUtils.h
Removed:
################################################################################
diff --git a/llvm/include/llvm/CodeGen/DIE.h b/llvm/include/llvm/CodeGen/DIE.h
index 40f6b041e9b3..e9e87256af0f 100644
--- a/llvm/include/llvm/CodeGen/DIE.h
+++ b/llvm/include/llvm/CodeGen/DIE.h
@@ -910,6 +910,9 @@ class DIELoc : public DIEValueList {
///
unsigned ComputeSize(const AsmPrinter *AP) const;
+ // TODO: move setSize() and Size to DIEValueList.
+ void setSize(unsigned size) { Size = size; }
+
/// BestForm - Choose the best form for data.
///
dwarf::Form BestForm(unsigned DwarfVersion) const {
@@ -944,6 +947,9 @@ class DIEBlock : public DIEValueList {
///
unsigned ComputeSize(const AsmPrinter *AP) const;
+ // TODO: move setSize() and Size to DIEValueList.
+ void setSize(unsigned size) { Size = size; }
+
/// BestForm - Choose the best form for data.
///
dwarf::Form BestForm() const {
diff --git a/llvm/include/llvm/DWARFLinker/DWARFLinker.h b/llvm/include/llvm/DWARFLinker/DWARFLinker.h
index 80df01ca0539..84618d8fe6ac 100644
--- a/llvm/include/llvm/DWARFLinker/DWARFLinker.h
+++ b/llvm/include/llvm/DWARFLinker/DWARFLinker.h
@@ -21,6 +21,13 @@ namespace llvm {
enum class DwarfLinkerClient { Dsymutil, LLD, General };
+/// The kind of accelerator tables we should emit.
+enum class AccelTableKind {
+ Apple, ///< .apple_names, .apple_namespaces, .apple_types, .apple_objc.
+ Dwarf, ///< DWARF v5 .debug_names.
+ Default, ///< Dwarf for DWARF5 or later, Apple otherwise.
+};
+
/// Partial address range. Besides an offset, only the
/// HighPC is stored. The structure is stored in a map where the LowPC is the
/// key.
@@ -193,6 +200,599 @@ class DwarfEmitter {
virtual uint64_t getDebugInfoSectionSize() const = 0;
};
+using UnitListTy = std::vector<std::unique_ptr<CompileUnit>>;
+
+/// this class represents Object File and it`s additional info.
+class DwarfLinkerObjFile {
+public:
+ DwarfLinkerObjFile(StringRef Name, const object::ObjectFile *File,
+ const std::vector<std::string> &Warnings)
+ : FileName(Name), ObjFile(File), Warnings(Warnings) {}
+
+ /// object file name.
+ StringRef FileName;
+ /// object file.
+ const object::ObjectFile *ObjFile;
+ /// helpful address information(list of valid address ranges, relocations).
+ std::unique_ptr<AddressesMap> Addresses;
+ /// warnings for object file.
+ const std::vector<std::string> &Warnings;
+};
+
+typedef std::function<void(const Twine &Warning, StringRef Context,
+ const DWARFDie *DIE)>
+ messageHandler;
+typedef std::function<ErrorOr<DwarfLinkerObjFile &>(StringRef ContainerName,
+ StringRef Path)>
+ objFileLoader;
+typedef std::map<std::string, std::string> swiftInterfacesMap;
+
+/// The core of the Dwarf linking logic.
+///
+/// The generation of the dwarf information from the object files will be
+/// driven by the selection of 'root DIEs', which are DIEs that
+/// describe variables or functions that resolves to the corresponding
+/// code section(and thus have entries in the Addresses map). All the debug
+/// information that will be generated(the DIEs, but also the line
+/// tables, ranges, ...) is derived from that set of root DIEs.
+///
+/// The root DIEs are identified because they contain relocations that
+/// points to code section(the low_pc for a function, the location for
+/// a variable). These relocations are called ValidRelocs in the
+/// AddressesInfo and are gathered as a very first step when we start
+/// processing a object file.
+class DWARFLinker {
+public:
+ DWARFLinker(const Triple &Triple, DwarfEmitter *Emitter,
+ DwarfLinkerClient ClientID = DwarfLinkerClient::General)
+ : Triple(Triple), DwarfEmitter(Emitter), DwarfLinkerClientID(ClientID) {}
+
+ /// Add object file to be linked.
+ void addObjectFile(DwarfLinkerObjFile &ObjFile);
+
+ /// Link debug info for added objFiles. Object
+ /// files are linked all together.
+ bool link();
+
+ /// A number of methods setting various linking options:
+
+ /// Allows to generate log of linking process to the standard output.
+ void setVerbosity(bool Verbose) { Options.Verbose = Verbose; }
+
+ /// Do not emit linked dwarf info.
+ void setNoOutput(bool NoOut) { Options.NoOutput = NoOut; }
+
+ /// Do not unique types according to ODR.
+ void setNoODR(bool NoODR) { Options.NoODR = NoODR; }
+
+ /// update existing DWARF info(for the linked binary).
+ void setUpdate(bool Update) { Options.Update = Update; }
+
+ /// Use specified number of threads for parallel files linking.
+ void setNumThreads(unsigned NumThreads) { Options.Threads = NumThreads; }
+
+ /// Set kind of accelerator tables to be generated.
+ void setAccelTableKind(AccelTableKind Kind) {
+ Options.TheAccelTableKind = Kind;
+ }
+
+ /// Set prepend path for clang modules.
+ void setPrependPath(const std::string &Ppath) { Options.PrependPath = Ppath; }
+
+ /// Set translator which would be used for strings.
+ void
+ setStringsTranslator(std::function<StringRef(StringRef)> StringsTranslator) {
+ this->StringsTranslator = StringsTranslator;
+ }
+
+ /// Set estimated objects files amount, for preliminary data allocation.
+ void setEstimatedObjfilesAmount(unsigned ObjFilesNum) {
+ ObjectContexts.reserve(ObjFilesNum);
+ }
+
+ /// Set warning handler which would be used to report warnings.
+ void setWarningHandler(messageHandler Handler) {
+ Options.WarningHandler = Handler;
+ }
+
+ /// Set error handler which would be used to report errors.
+ void setErrorHandler(messageHandler Handler) {
+ Options.ErrorHandler = Handler;
+ }
+
+ /// Set object files loader which would be used to load
+ /// additional objects for splitted dwarf.
+ void setObjFileLoader(objFileLoader Loader) {
+ Options.ObjFileLoader = Loader;
+ }
+
+ /// Set map for Swift interfaces.
+ void setSwiftInterfacesMap(swiftInterfacesMap *Map) {
+ Options.ParseableSwiftInterfaces = Map;
+ }
+
+private:
+ /// Flags passed to DwarfLinker::lookForDIEsToKeep
+ enum TraversalFlags {
+ TF_Keep = 1 << 0, ///< Mark the traversed DIEs as kept.
+ TF_InFunctionScope = 1 << 1, ///< Current scope is a function scope.
+ TF_DependencyWalk = 1 << 2, ///< Walking the dependencies of a kept DIE.
+ TF_ParentWalk = 1 << 3, ///< Walking up the parents of a kept DIE.
+ TF_ODR = 1 << 4, ///< Use the ODR while keeping dependents.
+ TF_SkipPC = 1 << 5, ///< Skip all location attributes.
+ };
+
+ /// The distinct types of work performed by the work loop.
+ enum class WorklistItemType {
+ /// Given a DIE, look for DIEs to be kept.
+ LookForDIEsToKeep,
+ /// Given a DIE, look for children of this DIE to be kept.
+ LookForChildDIEsToKeep,
+ /// Given a DIE, look for DIEs referencing this DIE to be kept.
+ LookForRefDIEsToKeep,
+ /// Given a DIE, look for parent DIEs to be kept.
+ LookForParentDIEsToKeep,
+ /// Given a DIE, update its incompleteness based on whether its children are
+ /// incomplete.
+ UpdateChildIncompleteness,
+ /// Given a DIE, update its incompleteness based on whether the DIEs it
+ /// references are incomplete.
+ UpdateRefIncompleteness,
+ };
+
+ /// This class represents an item in the work list. The type defines what kind
+ /// of work needs to be performed when processing the current item. The flags
+ /// and info fields are optional based on the type.
+ struct WorklistItem {
+ WorklistItemType Type;
+ DWARFDie Die;
+ CompileUnit &CU;
+ unsigned Flags;
+ unsigned AncestorIdx = 0;
+ CompileUnit::DIEInfo *OtherInfo = nullptr;
+
+ WorklistItem(DWARFDie Die, CompileUnit &CU, unsigned Flags,
+ WorklistItemType T = WorklistItemType::LookForDIEsToKeep)
+ : Type(T), Die(Die), CU(CU), Flags(Flags) {}
+
+ WorklistItem(DWARFDie Die, CompileUnit &CU, WorklistItemType T,
+ CompileUnit::DIEInfo *OtherInfo = nullptr)
+ : Type(T), Die(Die), CU(CU), OtherInfo(OtherInfo) {}
+
+ WorklistItem(unsigned AncestorIdx, CompileUnit &CU, unsigned Flags)
+ : Type(WorklistItemType::LookForParentDIEsToKeep), CU(CU), Flags(Flags),
+ AncestorIdx(AncestorIdx) {}
+ };
+
+ /// returns true if we need to translate strings.
+ bool needToTranslateStrings() { return StringsTranslator != nullptr; }
+
+ void reportWarning(const Twine &Warning, const DwarfLinkerObjFile &OF,
+ const DWARFDie *DIE = nullptr) const {
+ if (Options.WarningHandler != nullptr)
+ Options.WarningHandler(Warning, OF.FileName, DIE);
+ }
+
+ void reportError(const Twine &Warning, const DwarfLinkerObjFile &OF,
+ const DWARFDie *DIE = nullptr) const {
+ if (Options.ErrorHandler != nullptr)
+ Options.ErrorHandler(Warning, OF.FileName, DIE);
+ }
+
+ /// Remembers the oldest and newest DWARF version we've seen in a unit.
+ void updateDwarfVersion(unsigned Version) {
+ MaxDwarfVersion = std::max(MaxDwarfVersion, Version);
+ MinDwarfVersion = std::min(MinDwarfVersion, Version);
+ }
+
+ /// Remembers the kinds of accelerator tables we've seen in a unit.
+ void updateAccelKind(DWARFContext &Dwarf);
+
+ /// Emit warnings as Dwarf compile units to leave a trail after linking.
+ bool emitPaperTrailWarnings(const DwarfLinkerObjFile &OF,
+ OffsetsStringPool &StringPool);
+
+ void copyInvariantDebugSection(const object::ObjectFile &Obj);
+
+ /// Keeps track of data associated with one object during linking.
+ struct LinkContext {
+ DwarfLinkerObjFile &ObjectFile;
+ std::unique_ptr<DWARFContext> DwarfContext;
+ UnitListTy CompileUnits;
+ bool Skip = false;
+
+ LinkContext(DwarfLinkerObjFile &objFile) : ObjectFile(objFile) {
+
+ if (ObjectFile.ObjFile)
+ DwarfContext = DWARFContext::create(*ObjectFile.ObjFile);
+ }
+
+ /// Clear part of the context that's no longer needed when we're done with
+ /// the debug object.
+ void clear() {
+ DwarfContext.reset(nullptr);
+ CompileUnits.clear();
+ ObjectFile.Addresses->clear();
+ }
+ };
+
+ /// Called before emitting object data
+ void cleanupAuxiliarryData(LinkContext &Context);
+
+ /// Look at the parent of the given DIE and decide whether they should be
+ /// kept.
+ void lookForParentDIEsToKeep(unsigned AncestorIdx, CompileUnit &CU,
+ unsigned Flags,
+ SmallVectorImpl<WorklistItem> &Worklist);
+
+ /// Look at the children of the given DIE and decide whether they should be
+ /// kept.
+ void lookForChildDIEsToKeep(const DWARFDie &Die, CompileUnit &CU,
+ unsigned Flags,
+ SmallVectorImpl<WorklistItem> &Worklist);
+
+ /// Look at DIEs referenced by the given DIE and decide whether they should be
+ /// kept. All DIEs referenced though attributes should be kept.
+ void lookForRefDIEsToKeep(const DWARFDie &Die, CompileUnit &CU,
+ unsigned Flags, const UnitListTy &Units,
+ const DwarfLinkerObjFile &OF,
+ SmallVectorImpl<WorklistItem> &Worklist);
+
+ /// \defgroup FindRootDIEs Find DIEs corresponding to Address map entries.
+ ///
+ /// @{
+ /// Recursively walk the \p DIE tree and look for DIEs to
+ /// keep. Store that information in \p CU's DIEInfo.
+ ///
+ /// The return value indicates whether the DIE is incomplete.
+ void lookForDIEsToKeep(AddressesMap &RelocMgr, RangesTy &Ranges,
+ const UnitListTy &Units, const DWARFDie &DIE,
+ const DwarfLinkerObjFile &OF, CompileUnit &CU,
+ unsigned Flags);
+
+ /// If this compile unit is really a skeleton CU that points to a
+ /// clang module, register it in ClangModules and return true.
+ ///
+ /// A skeleton CU is a CU without children, a DW_AT_gnu_dwo_name
+ /// pointing to the module, and a DW_AT_gnu_dwo_id with the module
+ /// hash.
+ bool registerModuleReference(DWARFDie CUDie, const DWARFUnit &Unit,
+ const DwarfLinkerObjFile &OF,
+ OffsetsStringPool &OffsetsStringPool,
+ UniquingStringPool &UniquingStringPoolStringPool,
+ DeclContextTree &ODRContexts,
+ uint64_t ModulesEndOffset, unsigned &UnitID,
+ bool IsLittleEndian, unsigned Indent = 0,
+ bool Quiet = false);
+
+ /// Recursively add the debug info in this clang module .pcm
+ /// file (and all the modules imported by it in a bottom-up fashion)
+ /// to Units.
+ Error loadClangModule(DWARFDie CUDie, StringRef FilePath,
+ StringRef ModuleName, uint64_t DwoId,
+ const DwarfLinkerObjFile &OF,
+ OffsetsStringPool &OffsetsStringPool,
+ UniquingStringPool &UniquingStringPool,
+ DeclContextTree &ODRContexts, uint64_t ModulesEndOffset,
+ unsigned &UnitID, bool IsLittleEndian,
+ unsigned Indent = 0, bool Quiet = false);
+
+ /// Mark the passed DIE as well as all the ones it depends on as kept.
+ void keepDIEAndDependencies(AddressesMap &RelocMgr, RangesTy &Ranges,
+ const UnitListTy &Units, const DWARFDie &DIE,
+ CompileUnit::DIEInfo &MyInfo,
+ const DwarfLinkerObjFile &OF, CompileUnit &CU,
+ bool UseODR);
+
+ unsigned shouldKeepDIE(AddressesMap &RelocMgr, RangesTy &Ranges,
+ const DWARFDie &DIE, const DwarfLinkerObjFile &OF,
+ CompileUnit &Unit, CompileUnit::DIEInfo &MyInfo,
+ unsigned Flags);
+
+ /// Check if a variable describing DIE should be kept.
+ /// \returns updated TraversalFlags.
+ unsigned shouldKeepVariableDIE(AddressesMap &RelocMgr, const DWARFDie &DIE,
+ CompileUnit &Unit,
+ CompileUnit::DIEInfo &MyInfo, unsigned Flags);
+
+ unsigned shouldKeepSubprogramDIE(AddressesMap &RelocMgr, RangesTy &Ranges,
+ const DWARFDie &DIE,
+ const DwarfLinkerObjFile &OF,
+ CompileUnit &Unit,
+ CompileUnit::DIEInfo &MyInfo,
+ unsigned Flags);
+
+ /// Resolve the DIE attribute reference that has been extracted in \p
+ /// RefValue. The resulting DIE might be in another CompileUnit which is
+ /// stored into \p ReferencedCU. \returns null if resolving fails for any
+ /// reason.
+ DWARFDie resolveDIEReference(const DwarfLinkerObjFile &OF,
+ const UnitListTy &Units,
+ const DWARFFormValue &RefValue,
+ const DWARFDie &DIE, CompileUnit *&RefCU);
+
+ /// @}
+
+ /// \defgroup Methods used to link the debug information
+ ///
+ /// @{
+
+ struct DWARFLinkerOptions;
+
+ class DIECloner {
+ DWARFLinker &Linker;
+ DwarfEmitter *Emitter;
+ DwarfLinkerObjFile &ObjFile;
+
+ /// Allocator used for all the DIEValue objects.
+ BumpPtrAllocator &DIEAlloc;
+
+ std::vector<std::unique_ptr<CompileUnit>> &CompileUnits;
+
+ bool Update;
+
+ public:
+ DIECloner(DWARFLinker &Linker, DwarfEmitter *Emitter,
+ DwarfLinkerObjFile &ObjFile, BumpPtrAllocator &DIEAlloc,
+ std::vector<std::unique_ptr<CompileUnit>> &CompileUnits,
+ bool Update)
+ : Linker(Linker), Emitter(Emitter), ObjFile(ObjFile),
+ DIEAlloc(DIEAlloc), CompileUnits(CompileUnits), Update(Update) {}
+
+ /// Recursively clone \p InputDIE into an tree of DIE objects
+ /// where useless (as decided by lookForDIEsToKeep()) bits have been
+ /// stripped out and addresses have been rewritten according to the
+ /// address map.
+ ///
+ /// \param OutOffset is the offset the cloned DIE in the output
+ /// compile unit.
+ /// \param PCOffset (while cloning a function scope) is the offset
+ /// applied to the entry point of the function to get the linked address.
+ /// \param Die the output DIE to use, pass NULL to create one.
+ /// \returns the root of the cloned tree or null if nothing was selected.
+ DIE *cloneDIE(const DWARFDie &InputDIE, const DwarfLinkerObjFile &OF,
+ CompileUnit &U, OffsetsStringPool &StringPool,
+ int64_t PCOffset, uint32_t OutOffset, unsigned Flags,
+ bool IsLittleEndian, DIE *Die = nullptr);
+
+ /// Construct the output DIE tree by cloning the DIEs we
+ /// chose to keep above. If there are no valid relocs, then there's
+ /// nothing to clone/emit.
+ void cloneAllCompileUnits(DWARFContext &DwarfContext,
+ const DwarfLinkerObjFile &OF,
+ OffsetsStringPool &StringPool,
+ bool IsLittleEndian);
+
+ private:
+ using AttributeSpec = DWARFAbbreviationDeclaration::AttributeSpec;
+
+ /// Information gathered and exchanged between the various
+ /// clone*Attributes helpers about the attributes of a particular DIE.
+ struct AttributesInfo {
+ /// Names.
+ DwarfStringPoolEntryRef Name, MangledName, NameWithoutTemplate;
+
+ /// Offsets in the string pool.
+ uint32_t NameOffset = 0;
+ uint32_t MangledNameOffset = 0;
+
+ /// Value of AT_low_pc in the input DIE
+ uint64_t OrigLowPc = std::numeric_limits<uint64_t>::max();
+
+ /// Value of AT_high_pc in the input DIE
+ uint64_t OrigHighPc = 0;
+
+ /// Offset to apply to PC addresses inside a function.
+ int64_t PCOffset = 0;
+
+ /// Does the DIE have a low_pc attribute?
+ bool HasLowPc = false;
+
+ /// Does the DIE have a ranges attribute?
+ bool HasRanges = false;
+
+ /// Is this DIE only a declaration?
+ bool IsDeclaration = false;
+
+ AttributesInfo() = default;
+ };
+
+ friend DIECloner;
+
+ /// Helper for cloneDIE.
+ unsigned cloneAttribute(DIE &Die, const DWARFDie &InputDIE,
+ const DwarfLinkerObjFile &OF, CompileUnit &U,
+ OffsetsStringPool &StringPool,
+ const DWARFFormValue &Val,
+ const AttributeSpec AttrSpec, unsigned AttrSize,
+ AttributesInfo &AttrInfo, bool IsLittleEndian);
+
+ /// Clone a string attribute described by \p AttrSpec and add
+ /// it to \p Die.
+ /// \returns the size of the new attribute.
+ unsigned cloneStringAttribute(DIE &Die, AttributeSpec AttrSpec,
+ const DWARFFormValue &Val, const DWARFUnit &U,
+ OffsetsStringPool &StringPool,
+ AttributesInfo &Info);
+
+ /// Clone an attribute referencing another DIE and add
+ /// it to \p Die.
+ /// \returns the size of the new attribute.
+ unsigned cloneDieReferenceAttribute(DIE &Die, const DWARFDie &InputDIE,
+ AttributeSpec AttrSpec,
+ unsigned AttrSize,
+ const DWARFFormValue &Val,
+ const DwarfLinkerObjFile &OF,
+ CompileUnit &Unit);
+
+ /// Clone a DWARF expression that may be referencing another DIE.
+ void cloneExpression(DataExtractor &Data, DWARFExpression Expression,
+ const DwarfLinkerObjFile &OF, CompileUnit &Unit,
+ SmallVectorImpl<uint8_t> &OutputBuffer);
+
+ /// Clone an attribute referencing another DIE and add
+ /// it to \p Die.
+ /// \returns the size of the new attribute.
+ unsigned cloneBlockAttribute(DIE &Die, const DwarfLinkerObjFile &OF,
+ CompileUnit &Unit, AttributeSpec AttrSpec,
+ const DWARFFormValue &Val, unsigned AttrSize,
+ bool IsLittleEndian);
+
+ /// Clone an attribute referencing another DIE and add
+ /// it to \p Die.
+ /// \returns the size of the new attribute.
+ unsigned cloneAddressAttribute(DIE &Die, AttributeSpec AttrSpec,
+ const DWARFFormValue &Val,
+ const CompileUnit &Unit,
+ AttributesInfo &Info);
+
+ /// Clone a scalar attribute and add it to \p Die.
+ /// \returns the size of the new attribute.
+ unsigned cloneScalarAttribute(DIE &Die, const DWARFDie &InputDIE,
+ const DwarfLinkerObjFile &OF, CompileUnit &U,
+ AttributeSpec AttrSpec,
+ const DWARFFormValue &Val, unsigned AttrSize,
+ AttributesInfo &Info);
+
+ /// Get the potential name and mangled name for the entity
+ /// described by \p Die and store them in \Info if they are not
+ /// already there.
+ /// \returns is a name was found.
+ bool getDIENames(const DWARFDie &Die, AttributesInfo &Info,
+ OffsetsStringPool &StringPool, bool StripTemplate = false);
+
+ /// Create a copy of abbreviation Abbrev.
+ void copyAbbrev(const DWARFAbbreviationDeclaration &Abbrev, bool hasODR);
+
+ uint32_t hashFullyQualifiedName(DWARFDie DIE, CompileUnit &U,
+ const DwarfLinkerObjFile &OF,
+ int RecurseDepth = 0);
+
+ /// Helper for cloneDIE.
+ void addObjCAccelerator(CompileUnit &Unit, const DIE *Die,
+ DwarfStringPoolEntryRef Name,
+ OffsetsStringPool &StringPool, bool SkipPubSection);
+ };
+
+ /// Assign an abbreviation number to \p Abbrev
+ void assignAbbrev(DIEAbbrev &Abbrev);
+
+ /// Compute and emit debug_ranges section for \p Unit, and
+ /// patch the attributes referencing it.
+ void patchRangesForUnit(const CompileUnit &Unit, DWARFContext &Dwarf,
+ const DwarfLinkerObjFile &OF) const;
+
+ /// Generate and emit the DW_AT_ranges attribute for a compile_unit if it had
+ /// one.
+ void generateUnitRanges(CompileUnit &Unit) const;
+
+ /// Extract the line tables from the original dwarf, extract the relevant
+ /// parts according to the linked function ranges and emit the result in the
+ /// debug_line section.
+ void patchLineTableForUnit(CompileUnit &Unit, DWARFContext &OrigDwarf,
+ const DwarfLinkerObjFile &OF);
+
+ /// Emit the accelerator entries for \p Unit.
+ void emitAcceleratorEntriesForUnit(CompileUnit &Unit);
+ void emitDwarfAcceleratorEntriesForUnit(CompileUnit &Unit);
+ void emitAppleAcceleratorEntriesForUnit(CompileUnit &Unit);
+
+ /// Patch the frame info for an object file and emit it.
+ void patchFrameInfoForObject(const DwarfLinkerObjFile &, RangesTy &Ranges,
+ DWARFContext &, unsigned AddressSize);
+
+ /// FoldingSet that uniques the abbreviations.
+ FoldingSet<DIEAbbrev> AbbreviationsSet;
+
+ /// Storage for the unique Abbreviations.
+ /// This is passed to AsmPrinter::emitDwarfAbbrevs(), thus it cannot be
+ /// changed to a vector of unique_ptrs.
+ std::vector<std::unique_ptr<DIEAbbrev>> Abbreviations;
+
+ /// DIELoc objects that need to be destructed (but not freed!).
+ std::vector<DIELoc *> DIELocs;
+
+ /// DIEBlock objects that need to be destructed (but not freed!).
+ std::vector<DIEBlock *> DIEBlocks;
+
+ /// Allocator used for all the DIEValue objects.
+ BumpPtrAllocator DIEAlloc;
+ /// @}
+
+ Triple Triple;
+
+ DwarfEmitter *DwarfEmitter;
+ std::vector<LinkContext> ObjectContexts;
+
+ unsigned MaxDwarfVersion = 0;
+ unsigned MinDwarfVersion = std::numeric_limits<unsigned>::max();
+
+ bool AtLeastOneAppleAccelTable = false;
+ bool AtLeastOneDwarfAccelTable = false;
+
+ /// The CIEs that have been emitted in the output section. The actual CIE
+ /// data serves a the key to this StringMap, this takes care of comparing the
+ /// semantics of CIEs defined in
diff erent object files.
+ StringMap<uint32_t> EmittedCIEs;
+
+ /// Offset of the last CIE that has been emitted in the output
+ /// debug_frame section.
+ uint32_t LastCIEOffset = 0;
+
+ /// Apple accelerator tables.
+ AccelTable<DWARF5AccelTableStaticData> DebugNames;
+ AccelTable<AppleAccelTableStaticOffsetData> AppleNames;
+ AccelTable<AppleAccelTableStaticOffsetData> AppleNamespaces;
+ AccelTable<AppleAccelTableStaticOffsetData> AppleObjc;
+ AccelTable<AppleAccelTableStaticTypeData> AppleTypes;
+
+ /// Mapping the PCM filename to the DwoId.
+ StringMap<uint64_t> ClangModules;
+
+ DwarfLinkerClient DwarfLinkerClientID;
+
+ std::function<StringRef(StringRef)> StringsTranslator = nullptr;
+
+ /// linking options
+ struct DWARFLinkerOptions {
+ /// Generate processing log to the standard output.
+ bool Verbose = false;
+
+ /// Skip emitting output
+ bool NoOutput = false;
+
+ /// Do not unique types according to ODR
+ bool NoODR = false;
+
+ /// Update
+ bool Update = false;
+
+ /// Number of threads.
+ unsigned Threads = 1;
+
+ /// The accelerator table kind
+ AccelTableKind TheAccelTableKind = AccelTableKind::Default;
+
+ /// Prepend path for the clang modules.
+ std::string PrependPath;
+
+ // warning handler
+ messageHandler WarningHandler = nullptr;
+
+ // error handler
+ messageHandler ErrorHandler = nullptr;
+
+ objFileLoader ObjFileLoader = nullptr;
+
+ /// A list of all .swiftinterface files referenced by the debug
+ /// info, mapping Module name to path on disk. The entries need to
+ /// be uniqued and sorted and there are only few entries expected
+ /// per compile unit, which is why this is a std::map.
+ /// this is dsymutil specific fag.
+ swiftInterfacesMap *ParseableSwiftInterfaces = nullptr;
+ } Options;
+};
+
} // end namespace llvm
#endif // LLVM_DWARFLINKER_DWARFLINKER_H
diff --git a/llvm/lib/DWARFLinker/DWARFLinker.cpp b/llvm/lib/DWARFLinker/DWARFLinker.cpp
index 65b2a1bdf1fc..84f866293ce2 100644
--- a/llvm/lib/DWARFLinker/DWARFLinker.cpp
+++ b/llvm/lib/DWARFLinker/DWARFLinker.cpp
@@ -7,11 +7,2450 @@
//===----------------------------------------------------------------------===//
#include "llvm/DWARFLinker/DWARFLinker.h"
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/BitVector.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/CodeGen/NonRelocatableStringpool.h"
+#include "llvm/DWARFLinker/DWARFLinkerDeclContext.h"
+#include "llvm/DebugInfo/DWARF/DWARFAbbreviationDeclaration.h"
+#include "llvm/DebugInfo/DWARF/DWARFContext.h"
+#include "llvm/DebugInfo/DWARF/DWARFDataExtractor.h"
+#include "llvm/DebugInfo/DWARF/DWARFDebugLine.h"
+#include "llvm/DebugInfo/DWARF/DWARFDebugRangeList.h"
+#include "llvm/DebugInfo/DWARF/DWARFDie.h"
+#include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
+#include "llvm/DebugInfo/DWARF/DWARFSection.h"
+#include "llvm/DebugInfo/DWARF/DWARFUnit.h"
+#include "llvm/Object/ObjectFile.h"
+#include "llvm/Support/DataExtractor.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/ErrorOr.h"
+#include "llvm/Support/LEB128.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/ThreadPool.h"
+#include <vector>
namespace llvm {
+/// Similar to DWARFUnitSection::getUnitForOffset(), but returning our
+/// CompileUnit object instead.
+static CompileUnit *getUnitForOffset(const UnitListTy &Units, uint64_t Offset) {
+ auto CU = std::upper_bound(
+ Units.begin(), Units.end(), Offset,
+ [](uint64_t LHS, const std::unique_ptr<CompileUnit> &RHS) {
+ return LHS < RHS->getOrigUnit().getNextUnitOffset();
+ });
+ return CU != Units.end() ? CU->get() : nullptr;
+}
+
+/// Resolve the DIE attribute reference that has been extracted in \p RefValue.
+/// The resulting DIE might be in another CompileUnit which is stored into \p
+/// ReferencedCU. \returns null if resolving fails for any reason.
+DWARFDie DWARFLinker::resolveDIEReference(const DwarfLinkerObjFile &OF,
+ const UnitListTy &Units,
+ const DWARFFormValue &RefValue,
+ const DWARFDie &DIE,
+ CompileUnit *&RefCU) {
+ assert(RefValue.isFormClass(DWARFFormValue::FC_Reference));
+ uint64_t RefOffset = *RefValue.getAsReference();
+ if ((RefCU = getUnitForOffset(Units, RefOffset)))
+ if (const auto RefDie = RefCU->getOrigUnit().getDIEForOffset(RefOffset)) {
+ // In a file with broken references, an attribute might point to a NULL
+ // DIE.
+ if (!RefDie.isNULL())
+ return RefDie;
+ }
+
+ reportWarning("could not find referenced DIE", OF, &DIE);
+ return DWARFDie();
+}
+
+/// \returns whether the passed \a Attr type might contain a DIE reference
+/// suitable for ODR uniquing.
+static bool isODRAttribute(uint16_t Attr) {
+ switch (Attr) {
+ default:
+ return false;
+ case dwarf::DW_AT_type:
+ case dwarf::DW_AT_containing_type:
+ case dwarf::DW_AT_specification:
+ case dwarf::DW_AT_abstract_origin:
+ case dwarf::DW_AT_import:
+ return true;
+ }
+ llvm_unreachable("Improper attribute.");
+}
+
+static bool isTypeTag(uint16_t Tag) {
+ switch (Tag) {
+ case dwarf::DW_TAG_array_type:
+ case dwarf::DW_TAG_class_type:
+ case dwarf::DW_TAG_enumeration_type:
+ case dwarf::DW_TAG_pointer_type:
+ case dwarf::DW_TAG_reference_type:
+ case dwarf::DW_TAG_string_type:
+ case dwarf::DW_TAG_structure_type:
+ case dwarf::DW_TAG_subroutine_type:
+ case dwarf::DW_TAG_typedef:
+ case dwarf::DW_TAG_union_type:
+ case dwarf::DW_TAG_ptr_to_member_type:
+ case dwarf::DW_TAG_set_type:
+ case dwarf::DW_TAG_subrange_type:
+ case dwarf::DW_TAG_base_type:
+ case dwarf::DW_TAG_const_type:
+ case dwarf::DW_TAG_constant:
+ case dwarf::DW_TAG_file_type:
+ case dwarf::DW_TAG_namelist:
+ case dwarf::DW_TAG_packed_type:
+ case dwarf::DW_TAG_volatile_type:
+ case dwarf::DW_TAG_restrict_type:
+ case dwarf::DW_TAG_atomic_type:
+ case dwarf::DW_TAG_interface_type:
+ case dwarf::DW_TAG_unspecified_type:
+ case dwarf::DW_TAG_shared_type:
+ return true;
+ default:
+ break;
+ }
+ return false;
+}
+
AddressesMap::~AddressesMap() {}
DwarfEmitter::~DwarfEmitter() {}
+bool DWARFLinker::DIECloner::getDIENames(const DWARFDie &Die,
+ AttributesInfo &Info,
+ OffsetsStringPool &StringPool,
+ bool StripTemplate) {
+ // This function will be called on DIEs having low_pcs and
+ // ranges. As getting the name might be more expansive, filter out
+ // blocks directly.
+ if (Die.getTag() == dwarf::DW_TAG_lexical_block)
+ return false;
+
+ // FIXME: a bit wasteful as the first getName might return the
+ // short name.
+ if (!Info.MangledName)
+ if (const char *MangledName = Die.getName(DINameKind::LinkageName))
+ Info.MangledName = StringPool.getEntry(MangledName);
+
+ if (!Info.Name)
+ if (const char *Name = Die.getName(DINameKind::ShortName))
+ Info.Name = StringPool.getEntry(Name);
+
+ if (StripTemplate && Info.Name && Info.MangledName != Info.Name) {
+ // FIXME: dsymutil compatibility. This is wrong for operator<
+ auto Split = Info.Name.getString().split('<');
+ if (!Split.second.empty())
+ Info.NameWithoutTemplate = StringPool.getEntry(Split.first);
+ }
+
+ return Info.Name || Info.MangledName;
+}
+
+/// Resolve the relative path to a build artifact referenced by DWARF by
+/// applying DW_AT_comp_dir.
+static void resolveRelativeObjectPath(SmallVectorImpl<char> &Buf, DWARFDie CU) {
+ sys::path::append(Buf, dwarf::toString(CU.find(dwarf::DW_AT_comp_dir), ""));
+}
+
+/// Collect references to parseable Swift interfaces in imported
+/// DW_TAG_module blocks.
+static void analyzeImportedModule(
+ const DWARFDie &DIE, CompileUnit &CU,
+ swiftInterfacesMap *ParseableSwiftInterfaces,
+ std::function<void(const Twine &, const DWARFDie &)> ReportWarning) {
+ if (CU.getLanguage() != dwarf::DW_LANG_Swift)
+ return;
+
+ if (!ParseableSwiftInterfaces)
+ return;
+
+ StringRef Path = dwarf::toStringRef(DIE.find(dwarf::DW_AT_LLVM_include_path));
+ if (!Path.endswith(".swiftinterface"))
+ return;
+ if (Optional<DWARFFormValue> Val = DIE.find(dwarf::DW_AT_name))
+ if (Optional<const char *> Name = Val->getAsCString()) {
+ auto &Entry = (*ParseableSwiftInterfaces)[*Name];
+ // The prepend path is applied later when copying.
+ DWARFDie CUDie = CU.getOrigUnit().getUnitDIE();
+ SmallString<128> ResolvedPath;
+ if (sys::path::is_relative(Path))
+ resolveRelativeObjectPath(ResolvedPath, CUDie);
+ sys::path::append(ResolvedPath, Path);
+ if (!Entry.empty() && Entry != ResolvedPath)
+ ReportWarning(
+ Twine("Conflicting parseable interfaces for Swift Module ") +
+ *Name + ": " + Entry + " and " + Path,
+ DIE);
+ Entry = ResolvedPath.str();
+ }
+}
+
+/// Recursive helper to build the global DeclContext information and
+/// gather the child->parent relationships in the original compile unit.
+///
+/// \return true when this DIE and all of its children are only
+/// forward declarations to types defined in external clang modules
+/// (i.e., forward declarations that are children of a DW_TAG_module).
+static bool analyzeContextInfo(
+ const DWARFDie &DIE, unsigned ParentIdx, CompileUnit &CU,
+ DeclContext *CurrentDeclContext, UniquingStringPool &StringPool,
+ DeclContextTree &Contexts, uint64_t ModulesEndOffset,
+ swiftInterfacesMap *ParseableSwiftInterfaces,
+ std::function<void(const Twine &, const DWARFDie &)> ReportWarning,
+ bool InImportedModule = false) {
+ unsigned MyIdx = CU.getOrigUnit().getDIEIndex(DIE);
+ CompileUnit::DIEInfo &Info = CU.getInfo(MyIdx);
+
+ // Clang imposes an ODR on modules(!) regardless of the language:
+ // "The module-id should consist of only a single identifier,
+ // which provides the name of the module being defined. Each
+ // module shall have a single definition."
+ //
+ // This does not extend to the types inside the modules:
+ // "[I]n C, this implies that if two structs are defined in
+ //
diff erent submodules with the same name, those two types are
+ // distinct types (but may be compatible types if their
+ // definitions match)."
+ //
+ // We treat non-C++ modules like namespaces for this reason.
+ if (DIE.getTag() == dwarf::DW_TAG_module && ParentIdx == 0 &&
+ dwarf::toString(DIE.find(dwarf::DW_AT_name), "") !=
+ CU.getClangModuleName()) {
+ InImportedModule = true;
+ analyzeImportedModule(DIE, CU, ParseableSwiftInterfaces, ReportWarning);
+ }
+
+ Info.ParentIdx = ParentIdx;
+ bool InClangModule = CU.isClangModule() || InImportedModule;
+ if (CU.hasODR() || InClangModule) {
+ if (CurrentDeclContext) {
+ auto PtrInvalidPair = Contexts.getChildDeclContext(
+ *CurrentDeclContext, DIE, CU, StringPool, InClangModule);
+ CurrentDeclContext = PtrInvalidPair.getPointer();
+ Info.Ctxt =
+ PtrInvalidPair.getInt() ? nullptr : PtrInvalidPair.getPointer();
+ if (Info.Ctxt)
+ Info.Ctxt->setDefinedInClangModule(InClangModule);
+ } else
+ Info.Ctxt = CurrentDeclContext = nullptr;
+ }
+
+ Info.Prune = InImportedModule;
+ if (DIE.hasChildren())
+ for (auto Child : DIE.children())
+ Info.Prune &= analyzeContextInfo(Child, MyIdx, CU, CurrentDeclContext,
+ StringPool, Contexts, ModulesEndOffset,
+ ParseableSwiftInterfaces, ReportWarning,
+ InImportedModule);
+
+ // Prune this DIE if it is either a forward declaration inside a
+ // DW_TAG_module or a DW_TAG_module that contains nothing but
+ // forward declarations.
+ Info.Prune &= (DIE.getTag() == dwarf::DW_TAG_module) ||
+ (isTypeTag(DIE.getTag()) &&
+ dwarf::toUnsigned(DIE.find(dwarf::DW_AT_declaration), 0));
+
+ // Only prune forward declarations inside a DW_TAG_module for which a
+ // definition exists elsewhere.
+ if (ModulesEndOffset == 0)
+ Info.Prune &= Info.Ctxt && Info.Ctxt->getCanonicalDIEOffset();
+ else
+ Info.Prune &= Info.Ctxt && Info.Ctxt->getCanonicalDIEOffset() > 0 &&
+ Info.Ctxt->getCanonicalDIEOffset() <= ModulesEndOffset;
+
+ return Info.Prune;
+}
+
+static bool dieNeedsChildrenToBeMeaningful(uint32_t Tag) {
+ switch (Tag) {
+ default:
+ return false;
+ case dwarf::DW_TAG_class_type:
+ case dwarf::DW_TAG_common_block:
+ case dwarf::DW_TAG_lexical_block:
+ case dwarf::DW_TAG_structure_type:
+ case dwarf::DW_TAG_subprogram:
+ case dwarf::DW_TAG_subroutine_type:
+ case dwarf::DW_TAG_union_type:
+ return true;
+ }
+ llvm_unreachable("Invalid Tag");
+}
+
+void DWARFLinker::cleanupAuxiliarryData(LinkContext &Context) {
+ Context.clear();
+
+ for (auto I = DIEBlocks.begin(), E = DIEBlocks.end(); I != E; ++I)
+ (*I)->~DIEBlock();
+ for (auto I = DIELocs.begin(), E = DIELocs.end(); I != E; ++I)
+ (*I)->~DIELoc();
+
+ DIEBlocks.clear();
+ DIELocs.clear();
+ DIEAlloc.Reset();
+}
+
+/// Get the starting and ending (exclusive) offset for the
+/// attribute with index \p Idx descibed by \p Abbrev. \p Offset is
+/// supposed to point to the position of the first attribute described
+/// by \p Abbrev.
+/// \return [StartOffset, EndOffset) as a pair.
+static std::pair<uint64_t, uint64_t>
+getAttributeOffsets(const DWARFAbbreviationDeclaration *Abbrev, unsigned Idx,
+ uint64_t Offset, const DWARFUnit &Unit) {
+ DataExtractor Data = Unit.getDebugInfoExtractor();
+
+ for (unsigned I = 0; I < Idx; ++I)
+ DWARFFormValue::skipValue(Abbrev->getFormByIndex(I), Data, &Offset,
+ Unit.getFormParams());
+
+ uint64_t End = Offset;
+ DWARFFormValue::skipValue(Abbrev->getFormByIndex(Idx), Data, &End,
+ Unit.getFormParams());
+
+ return std::make_pair(Offset, End);
+}
+
+/// Check if a variable describing DIE should be kept.
+/// \returns updated TraversalFlags.
+unsigned DWARFLinker::shouldKeepVariableDIE(AddressesMap &RelocMgr,
+ const DWARFDie &DIE,
+ CompileUnit &Unit,
+ CompileUnit::DIEInfo &MyInfo,
+ unsigned Flags) {
+ const auto *Abbrev = DIE.getAbbreviationDeclarationPtr();
+
+ // Global variables with constant value can always be kept.
+ if (!(Flags & TF_InFunctionScope) &&
+ Abbrev->findAttributeIndex(dwarf::DW_AT_const_value)) {
+ MyInfo.InDebugMap = true;
+ return Flags | TF_Keep;
+ }
+
+ Optional<uint32_t> LocationIdx =
+ Abbrev->findAttributeIndex(dwarf::DW_AT_location);
+ if (!LocationIdx)
+ return Flags;
+
+ uint64_t Offset = DIE.getOffset() + getULEB128Size(Abbrev->getCode());
+ const DWARFUnit &OrigUnit = Unit.getOrigUnit();
+ uint64_t LocationOffset, LocationEndOffset;
+ std::tie(LocationOffset, LocationEndOffset) =
+ getAttributeOffsets(Abbrev, *LocationIdx, Offset, OrigUnit);
+
+ // See if there is a relocation to a valid debug map entry inside
+ // this variable's location. The order is important here. We want to
+ // always check if the variable has a valid relocation, so that the
+ // DIEInfo is filled. However, we don't want a static variable in a
+ // function to force us to keep the enclosing function.
+ if (!RelocMgr.hasValidRelocationAt(LocationOffset, LocationEndOffset,
+ MyInfo) ||
+ (Flags & TF_InFunctionScope))
+ return Flags;
+
+ if (Options.Verbose) {
+ outs() << "Keeping variable DIE:";
+ DIDumpOptions DumpOpts;
+ DumpOpts.ChildRecurseDepth = 0;
+ DumpOpts.Verbose = Options.Verbose;
+ DIE.dump(outs(), 8 /* Indent */, DumpOpts);
+ }
+
+ return Flags | TF_Keep;
+}
+
+/// Check if a function describing DIE should be kept.
+/// \returns updated TraversalFlags.
+unsigned DWARFLinker::shouldKeepSubprogramDIE(
+ AddressesMap &RelocMgr, RangesTy &Ranges, const DWARFDie &DIE,
+ const DwarfLinkerObjFile &OF, CompileUnit &Unit,
+ CompileUnit::DIEInfo &MyInfo, unsigned Flags) {
+ const auto *Abbrev = DIE.getAbbreviationDeclarationPtr();
+
+ Flags |= TF_InFunctionScope;
+
+ Optional<uint32_t> LowPcIdx = Abbrev->findAttributeIndex(dwarf::DW_AT_low_pc);
+ if (!LowPcIdx)
+ return Flags;
+
+ uint64_t Offset = DIE.getOffset() + getULEB128Size(Abbrev->getCode());
+ DWARFUnit &OrigUnit = Unit.getOrigUnit();
+ uint64_t LowPcOffset, LowPcEndOffset;
+ std::tie(LowPcOffset, LowPcEndOffset) =
+ getAttributeOffsets(Abbrev, *LowPcIdx, Offset, OrigUnit);
+
+ auto LowPc = dwarf::toAddress(DIE.find(dwarf::DW_AT_low_pc));
+ assert(LowPc.hasValue() && "low_pc attribute is not an address.");
+ if (!LowPc ||
+ !RelocMgr.hasValidRelocationAt(LowPcOffset, LowPcEndOffset, MyInfo))
+ return Flags;
+
+ if (Options.Verbose) {
+ outs() << "Keeping subprogram DIE:";
+ DIDumpOptions DumpOpts;
+ DumpOpts.ChildRecurseDepth = 0;
+ DumpOpts.Verbose = Options.Verbose;
+ DIE.dump(outs(), 8 /* Indent */, DumpOpts);
+ }
+
+ if (DIE.getTag() == dwarf::DW_TAG_label) {
+ if (Unit.hasLabelAt(*LowPc))
+ return Flags;
+ // FIXME: dsymutil-classic compat. dsymutil-classic doesn't consider labels
+ // that don't fall into the CU's aranges. This is wrong IMO. Debug info
+ // generation bugs aside, this is really wrong in the case of labels, where
+ // a label marking the end of a function will have a PC == CU's high_pc.
+ if (dwarf::toAddress(OrigUnit.getUnitDIE().find(dwarf::DW_AT_high_pc))
+ .getValueOr(UINT64_MAX) <= LowPc)
+ return Flags;
+ Unit.addLabelLowPc(*LowPc, MyInfo.AddrAdjust);
+ return Flags | TF_Keep;
+ }
+
+ Flags |= TF_Keep;
+
+ Optional<uint64_t> HighPc = DIE.getHighPC(*LowPc);
+ if (!HighPc) {
+ reportWarning("Function without high_pc. Range will be discarded.\n", OF,
+ &DIE);
+ return Flags;
+ }
+
+ // Replace the debug map range with a more accurate one.
+ Ranges[*LowPc] = ObjFileAddressRange(*HighPc, MyInfo.AddrAdjust);
+ Unit.addFunctionRange(*LowPc, *HighPc, MyInfo.AddrAdjust);
+ return Flags;
+}
+
+/// Check if a DIE should be kept.
+/// \returns updated TraversalFlags.
+unsigned DWARFLinker::shouldKeepDIE(AddressesMap &RelocMgr, RangesTy &Ranges,
+ const DWARFDie &DIE,
+ const DwarfLinkerObjFile &OF,
+ CompileUnit &Unit,
+ CompileUnit::DIEInfo &MyInfo,
+ unsigned Flags) {
+ switch (DIE.getTag()) {
+ case dwarf::DW_TAG_constant:
+ case dwarf::DW_TAG_variable:
+ return shouldKeepVariableDIE(RelocMgr, DIE, Unit, MyInfo, Flags);
+ case dwarf::DW_TAG_subprogram:
+ case dwarf::DW_TAG_label:
+ return shouldKeepSubprogramDIE(RelocMgr, Ranges, DIE, OF, Unit, MyInfo,
+ Flags);
+ case dwarf::DW_TAG_base_type:
+ // DWARF Expressions may reference basic types, but scanning them
+ // is expensive. Basic types are tiny, so just keep all of them.
+ case dwarf::DW_TAG_imported_module:
+ case dwarf::DW_TAG_imported_declaration:
+ case dwarf::DW_TAG_imported_unit:
+ // We always want to keep these.
+ return Flags | TF_Keep;
+ default:
+ break;
+ }
+
+ return Flags;
+}
+
+/// Helper that updates the completeness of the current DIE based on the
+/// completeness of one of its children. It depends on the incompleteness of
+/// the children already being computed.
+static void updateChildIncompleteness(const DWARFDie &Die, CompileUnit &CU,
+ CompileUnit::DIEInfo &ChildInfo) {
+ switch (Die.getTag()) {
+ case dwarf::DW_TAG_structure_type:
+ case dwarf::DW_TAG_class_type:
+ break;
+ default:
+ return;
+ }
+
+ unsigned Idx = CU.getOrigUnit().getDIEIndex(Die);
+ CompileUnit::DIEInfo &MyInfo = CU.getInfo(Idx);
+
+ if (ChildInfo.Incomplete || ChildInfo.Prune)
+ MyInfo.Incomplete = true;
+}
+
+/// Helper that updates the completeness of the current DIE based on the
+/// completeness of the DIEs it references. It depends on the incompleteness of
+/// the referenced DIE already being computed.
+static void updateRefIncompleteness(const DWARFDie &Die, CompileUnit &CU,
+ CompileUnit::DIEInfo &RefInfo) {
+ switch (Die.getTag()) {
+ case dwarf::DW_TAG_typedef:
+ case dwarf::DW_TAG_member:
+ case dwarf::DW_TAG_reference_type:
+ case dwarf::DW_TAG_ptr_to_member_type:
+ case dwarf::DW_TAG_pointer_type:
+ break;
+ default:
+ return;
+ }
+
+ unsigned Idx = CU.getOrigUnit().getDIEIndex(Die);
+ CompileUnit::DIEInfo &MyInfo = CU.getInfo(Idx);
+
+ if (MyInfo.Incomplete)
+ return;
+
+ if (RefInfo.Incomplete)
+ MyInfo.Incomplete = true;
+}
+
+/// Look at the children of the given DIE and decide whether they should be
+/// kept.
+void DWARFLinker::lookForChildDIEsToKeep(
+ const DWARFDie &Die, CompileUnit &CU, unsigned Flags,
+ SmallVectorImpl<WorklistItem> &Worklist) {
+ // The TF_ParentWalk flag tells us that we are currently walking up the
+ // parent chain of a required DIE, and we don't want to mark all the children
+ // of the parents as kept (consider for example a DW_TAG_namespace node in
+ // the parent chain). There are however a set of DIE types for which we want
+ // to ignore that directive and still walk their children.
+ if (dieNeedsChildrenToBeMeaningful(Die.getTag()))
+ Flags &= ~DWARFLinker::TF_ParentWalk;
+
+ // We're finished if this DIE has no children or we're walking the parent
+ // chain.
+ if (!Die.hasChildren() || (Flags & DWARFLinker::TF_ParentWalk))
+ return;
+
+ // Add children in reverse order to the worklist to effectively process them
+ // in order.
+ for (auto Child : reverse(Die.children())) {
+ // Add a worklist item before every child to calculate incompleteness right
+ // after the current child is processed.
+ unsigned Idx = CU.getOrigUnit().getDIEIndex(Child);
+ CompileUnit::DIEInfo &ChildInfo = CU.getInfo(Idx);
+ Worklist.emplace_back(Die, CU, WorklistItemType::UpdateChildIncompleteness,
+ &ChildInfo);
+ Worklist.emplace_back(Child, CU, Flags);
+ }
+}
+
+/// Look at DIEs referenced by the given DIE and decide whether they should be
+/// kept. All DIEs referenced though attributes should be kept.
+void DWARFLinker::lookForRefDIEsToKeep(
+ const DWARFDie &Die, CompileUnit &CU, unsigned Flags,
+ const UnitListTy &Units, const DwarfLinkerObjFile &OF,
+ SmallVectorImpl<WorklistItem> &Worklist) {
+ bool UseOdr = (Flags & DWARFLinker::TF_DependencyWalk)
+ ? (Flags & DWARFLinker::TF_ODR)
+ : CU.hasODR();
+ DWARFUnit &Unit = CU.getOrigUnit();
+ DWARFDataExtractor Data = Unit.getDebugInfoExtractor();
+ const auto *Abbrev = Die.getAbbreviationDeclarationPtr();
+ uint64_t Offset = Die.getOffset() + getULEB128Size(Abbrev->getCode());
+
+ SmallVector<std::pair<DWARFDie, CompileUnit &>, 4> ReferencedDIEs;
+ for (const auto &AttrSpec : Abbrev->attributes()) {
+ DWARFFormValue Val(AttrSpec.Form);
+ if (!Val.isFormClass(DWARFFormValue::FC_Reference) ||
+ AttrSpec.Attr == dwarf::DW_AT_sibling) {
+ DWARFFormValue::skipValue(AttrSpec.Form, Data, &Offset,
+ Unit.getFormParams());
+ continue;
+ }
+
+ Val.extractValue(Data, &Offset, Unit.getFormParams(), &Unit);
+ CompileUnit *ReferencedCU;
+ if (auto RefDie = resolveDIEReference(OF, Units, Val, Die, ReferencedCU)) {
+ uint32_t RefIdx = ReferencedCU->getOrigUnit().getDIEIndex(RefDie);
+ CompileUnit::DIEInfo &Info = ReferencedCU->getInfo(RefIdx);
+ bool IsModuleRef = Info.Ctxt && Info.Ctxt->getCanonicalDIEOffset() &&
+ Info.Ctxt->isDefinedInClangModule();
+ // If the referenced DIE has a DeclContext that has already been
+ // emitted, then do not keep the one in this CU. We'll link to
+ // the canonical DIE in cloneDieReferenceAttribute.
+ //
+ // FIXME: compatibility with dsymutil-classic. UseODR shouldn't
+ // be necessary and could be advantageously replaced by
+ // ReferencedCU->hasODR() && CU.hasODR().
+ //
+ // FIXME: compatibility with dsymutil-classic. There is no
+ // reason not to unique ref_addr references.
+ if (AttrSpec.Form != dwarf::DW_FORM_ref_addr && (UseOdr || IsModuleRef) &&
+ Info.Ctxt &&
+ Info.Ctxt != ReferencedCU->getInfo(Info.ParentIdx).Ctxt &&
+ Info.Ctxt->getCanonicalDIEOffset() && isODRAttribute(AttrSpec.Attr))
+ continue;
+
+ // Keep a module forward declaration if there is no definition.
+ if (!(isODRAttribute(AttrSpec.Attr) && Info.Ctxt &&
+ Info.Ctxt->getCanonicalDIEOffset()))
+ Info.Prune = false;
+ ReferencedDIEs.emplace_back(RefDie, *ReferencedCU);
+ }
+ }
+
+ unsigned ODRFlag = UseOdr ? DWARFLinker::TF_ODR : 0;
+
+ // Add referenced DIEs in reverse order to the worklist to effectively
+ // process them in order.
+ for (auto &P : reverse(ReferencedDIEs)) {
+ // Add a worklist item before every child to calculate incompleteness right
+ // after the current child is processed.
+ uint32_t RefIdx = P.second.getOrigUnit().getDIEIndex(P.first);
+ CompileUnit::DIEInfo &Info = P.second.getInfo(RefIdx);
+ Worklist.emplace_back(Die, CU, WorklistItemType::UpdateRefIncompleteness,
+ &Info);
+ Worklist.emplace_back(P.first, P.second,
+ DWARFLinker::TF_Keep |
+ DWARFLinker::TF_DependencyWalk | ODRFlag);
+ }
+}
+
+/// Look at the parent of the given DIE and decide whether they should be kept.
+void DWARFLinker::lookForParentDIEsToKeep(
+ unsigned AncestorIdx, CompileUnit &CU, unsigned Flags,
+ SmallVectorImpl<WorklistItem> &Worklist) {
+ // Stop if we encounter an ancestor that's already marked as kept.
+ if (CU.getInfo(AncestorIdx).Keep)
+ return;
+
+ DWARFUnit &Unit = CU.getOrigUnit();
+ DWARFDie ParentDIE = Unit.getDIEAtIndex(AncestorIdx);
+ Worklist.emplace_back(CU.getInfo(AncestorIdx).ParentIdx, CU, Flags);
+ Worklist.emplace_back(ParentDIE, CU, Flags);
+}
+
+/// Recursively walk the \p DIE tree and look for DIEs to keep. Store that
+/// information in \p CU's DIEInfo.
+///
+/// This function is the entry point of the DIE selection algorithm. It is
+/// expected to walk the DIE tree in file order and (though the mediation of
+/// its helper) call hasValidRelocation() on each DIE that might be a 'root
+/// DIE' (See DwarfLinker class comment).
+///
+/// While walking the dependencies of root DIEs, this function is also called,
+/// but during these dependency walks the file order is not respected. The
+/// TF_DependencyWalk flag tells us which kind of traversal we are currently
+/// doing.
+///
+/// The recursive algorithm is implemented iteratively as a work list because
+/// very deep recursion could exhaust the stack for large projects. The work
+/// list acts as a scheduler for
diff erent types of work that need to be
+/// performed.
+///
+/// The recursive nature of the algorithm is simulated by running the "main"
+/// algorithm (LookForDIEsToKeep) followed by either looking at more DIEs
+/// (LookForChildDIEsToKeep, LookForRefDIEsToKeep, LookForParentDIEsToKeep) or
+/// fixing up a computed property (UpdateChildIncompleteness,
+/// UpdateRefIncompleteness).
+///
+/// The return value indicates whether the DIE is incomplete.
+void DWARFLinker::lookForDIEsToKeep(AddressesMap &AddressesMap,
+ RangesTy &Ranges, const UnitListTy &Units,
+ const DWARFDie &Die,
+ const DwarfLinkerObjFile &OF,
+ CompileUnit &Cu, unsigned Flags) {
+ // LIFO work list.
+ SmallVector<WorklistItem, 4> Worklist;
+ Worklist.emplace_back(Die, Cu, Flags);
+
+ while (!Worklist.empty()) {
+ WorklistItem Current = Worklist.back();
+ Worklist.pop_back();
+
+ // Look at the worklist type to decide what kind of work to perform.
+ switch (Current.Type) {
+ case WorklistItemType::UpdateChildIncompleteness:
+ updateChildIncompleteness(Current.Die, Current.CU, *Current.OtherInfo);
+ continue;
+ case WorklistItemType::UpdateRefIncompleteness:
+ updateRefIncompleteness(Current.Die, Current.CU, *Current.OtherInfo);
+ continue;
+ case WorklistItemType::LookForChildDIEsToKeep:
+ lookForChildDIEsToKeep(Current.Die, Current.CU, Current.Flags, Worklist);
+ continue;
+ case WorklistItemType::LookForRefDIEsToKeep:
+ lookForRefDIEsToKeep(Current.Die, Current.CU, Current.Flags, Units, OF,
+ Worklist);
+ continue;
+ case WorklistItemType::LookForParentDIEsToKeep:
+ lookForParentDIEsToKeep(Current.AncestorIdx, Current.CU, Current.Flags,
+ Worklist);
+ continue;
+ case WorklistItemType::LookForDIEsToKeep:
+ break;
+ }
+
+ unsigned Idx = Current.CU.getOrigUnit().getDIEIndex(Current.Die);
+ CompileUnit::DIEInfo &MyInfo = Current.CU.getInfo(Idx);
+
+ if (MyInfo.Prune)
+ continue;
+
+ // If the Keep flag is set, we are marking a required DIE's dependencies.
+ // If our target is already marked as kept, we're all set.
+ bool AlreadyKept = MyInfo.Keep;
+ if ((Current.Flags & TF_DependencyWalk) && AlreadyKept)
+ continue;
+
+ // We must not call shouldKeepDIE while called from keepDIEAndDependencies,
+ // because it would screw up the relocation finding logic.
+ if (!(Current.Flags & TF_DependencyWalk))
+ Current.Flags = shouldKeepDIE(AddressesMap, Ranges, Current.Die, OF,
+ Current.CU, MyInfo, Current.Flags);
+
+ // Finish by looking for child DIEs. Because of the LIFO worklist we need
+ // to schedule that work before any subsequent items are added to the
+ // worklist.
+ Worklist.emplace_back(Current.Die, Current.CU, Current.Flags,
+ WorklistItemType::LookForChildDIEsToKeep);
+
+ if (AlreadyKept || !(Current.Flags & TF_Keep))
+ continue;
+
+ // If it is a newly kept DIE mark it as well as all its dependencies as
+ // kept.
+ MyInfo.Keep = true;
+
+ // We're looking for incomplete types.
+ MyInfo.Incomplete =
+ Current.Die.getTag() != dwarf::DW_TAG_subprogram &&
+ Current.Die.getTag() != dwarf::DW_TAG_member &&
+ dwarf::toUnsigned(Current.Die.find(dwarf::DW_AT_declaration), 0);
+
+ // After looking at the parent chain, look for referenced DIEs. Because of
+ // the LIFO worklist we need to schedule that work before any subsequent
+ // items are added to the worklist.
+ Worklist.emplace_back(Current.Die, Current.CU, Current.Flags,
+ WorklistItemType::LookForRefDIEsToKeep);
+
+ bool UseOdr = (Current.Flags & TF_DependencyWalk) ? (Current.Flags & TF_ODR)
+ : Current.CU.hasODR();
+ unsigned ODRFlag = UseOdr ? TF_ODR : 0;
+ unsigned ParFlags = TF_ParentWalk | TF_Keep | TF_DependencyWalk | ODRFlag;
+
+ // Now schedule the parent walk.
+ Worklist.emplace_back(MyInfo.ParentIdx, Current.CU, ParFlags);
+ }
+}
+
+/// Assign an abbreviation number to \p Abbrev.
+///
+/// Our DIEs get freed after every DebugMapObject has been processed,
+/// thus the FoldingSet we use to unique DIEAbbrevs cannot refer to
+/// the instances hold by the DIEs. When we encounter an abbreviation
+/// that we don't know, we create a permanent copy of it.
+void DWARFLinker::assignAbbrev(DIEAbbrev &Abbrev) {
+ // Check the set for priors.
+ FoldingSetNodeID ID;
+ Abbrev.Profile(ID);
+ void *InsertToken;
+ DIEAbbrev *InSet = AbbreviationsSet.FindNodeOrInsertPos(ID, InsertToken);
+
+ // If it's newly added.
+ if (InSet) {
+ // Assign existing abbreviation number.
+ Abbrev.setNumber(InSet->getNumber());
+ } else {
+ // Add to abbreviation list.
+ Abbreviations.push_back(
+ std::make_unique<DIEAbbrev>(Abbrev.getTag(), Abbrev.hasChildren()));
+ for (const auto &Attr : Abbrev.getData())
+ Abbreviations.back()->AddAttribute(Attr.getAttribute(), Attr.getForm());
+ AbbreviationsSet.InsertNode(Abbreviations.back().get(), InsertToken);
+ // Assign the unique abbreviation number.
+ Abbrev.setNumber(Abbreviations.size());
+ Abbreviations.back()->setNumber(Abbreviations.size());
+ }
+}
+
+unsigned DWARFLinker::DIECloner::cloneStringAttribute(
+ DIE &Die, AttributeSpec AttrSpec, const DWARFFormValue &Val,
+ const DWARFUnit &U, OffsetsStringPool &StringPool, AttributesInfo &Info) {
+ // Switch everything to out of line strings.
+ const char *String = *Val.getAsCString();
+ auto StringEntry = StringPool.getEntry(String);
+
+ // Update attributes info.
+ if (AttrSpec.Attr == dwarf::DW_AT_name)
+ Info.Name = StringEntry;
+ else if (AttrSpec.Attr == dwarf::DW_AT_MIPS_linkage_name ||
+ AttrSpec.Attr == dwarf::DW_AT_linkage_name)
+ Info.MangledName = StringEntry;
+
+ Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr), dwarf::DW_FORM_strp,
+ DIEInteger(StringEntry.getOffset()));
+
+ return 4;
+}
+
+unsigned DWARFLinker::DIECloner::cloneDieReferenceAttribute(
+ DIE &Die, const DWARFDie &InputDIE, AttributeSpec AttrSpec,
+ unsigned AttrSize, const DWARFFormValue &Val, const DwarfLinkerObjFile &OF,
+ CompileUnit &Unit) {
+ const DWARFUnit &U = Unit.getOrigUnit();
+ uint64_t Ref = *Val.getAsReference();
+
+ DIE *NewRefDie = nullptr;
+ CompileUnit *RefUnit = nullptr;
+ DeclContext *Ctxt = nullptr;
+
+ DWARFDie RefDie =
+ Linker.resolveDIEReference(OF, CompileUnits, Val, InputDIE, RefUnit);
+
+ // If the referenced DIE is not found, drop the attribute.
+ if (!RefDie || AttrSpec.Attr == dwarf::DW_AT_sibling)
+ return 0;
+
+ unsigned Idx = RefUnit->getOrigUnit().getDIEIndex(RefDie);
+ CompileUnit::DIEInfo &RefInfo = RefUnit->getInfo(Idx);
+
+ // If we already have emitted an equivalent DeclContext, just point
+ // at it.
+ if (isODRAttribute(AttrSpec.Attr)) {
+ Ctxt = RefInfo.Ctxt;
+ if (Ctxt && Ctxt->getCanonicalDIEOffset()) {
+ DIEInteger Attr(Ctxt->getCanonicalDIEOffset());
+ Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
+ dwarf::DW_FORM_ref_addr, Attr);
+ return U.getRefAddrByteSize();
+ }
+ }
+
+ if (!RefInfo.Clone) {
+ assert(Ref > InputDIE.getOffset());
+ // We haven't cloned this DIE yet. Just create an empty one and
+ // store it. It'll get really cloned when we process it.
+ RefInfo.Clone = DIE::get(DIEAlloc, dwarf::Tag(RefDie.getTag()));
+ }
+ NewRefDie = RefInfo.Clone;
+
+ if (AttrSpec.Form == dwarf::DW_FORM_ref_addr ||
+ (Unit.hasODR() && isODRAttribute(AttrSpec.Attr))) {
+ // We cannot currently rely on a DIEEntry to emit ref_addr
+ // references, because the implementation calls back to DwarfDebug
+ // to find the unit offset. (We don't have a DwarfDebug)
+ // FIXME: we should be able to design DIEEntry reliance on
+ // DwarfDebug away.
+ uint64_t Attr;
+ if (Ref < InputDIE.getOffset()) {
+ // We must have already cloned that DIE.
+ uint32_t NewRefOffset =
+ RefUnit->getStartOffset() + NewRefDie->getOffset();
+ Attr = NewRefOffset;
+ Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
+ dwarf::DW_FORM_ref_addr, DIEInteger(Attr));
+ } else {
+ // A forward reference. Note and fixup later.
+ Attr = 0xBADDEF;
+ Unit.noteForwardReference(
+ NewRefDie, RefUnit, Ctxt,
+ Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
+ dwarf::DW_FORM_ref_addr, DIEInteger(Attr)));
+ }
+ return U.getRefAddrByteSize();
+ }
+
+ Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
+ dwarf::Form(AttrSpec.Form), DIEEntry(*NewRefDie));
+
+ return AttrSize;
+}
+
+void DWARFLinker::DIECloner::cloneExpression(
+ DataExtractor &Data, DWARFExpression Expression,
+ const DwarfLinkerObjFile &OF, CompileUnit &Unit,
+ SmallVectorImpl<uint8_t> &OutputBuffer) {
+ using Encoding = DWARFExpression::Operation::Encoding;
+
+ uint64_t OpOffset = 0;
+ for (auto &Op : Expression) {
+ auto Description = Op.getDescription();
+ // DW_OP_const_type is variable-length and has 3
+ // operands. DWARFExpression thus far only supports 2.
+ auto Op0 = Description.Op[0];
+ auto Op1 = Description.Op[1];
+ if ((Op0 == Encoding::BaseTypeRef && Op1 != Encoding::SizeNA) ||
+ (Op1 == Encoding::BaseTypeRef && Op0 != Encoding::Size1))
+ Linker.reportWarning("Unsupported DW_OP encoding.", OF);
+
+ if ((Op0 == Encoding::BaseTypeRef && Op1 == Encoding::SizeNA) ||
+ (Op1 == Encoding::BaseTypeRef && Op0 == Encoding::Size1)) {
+ // This code assumes that the other non-typeref operand fits into 1 byte.
+ assert(OpOffset < Op.getEndOffset());
+ uint32_t ULEBsize = Op.getEndOffset() - OpOffset - 1;
+ assert(ULEBsize <= 16);
+
+ // Copy over the operation.
+ OutputBuffer.push_back(Op.getCode());
+ uint64_t RefOffset;
+ if (Op1 == Encoding::SizeNA) {
+ RefOffset = Op.getRawOperand(0);
+ } else {
+ OutputBuffer.push_back(Op.getRawOperand(0));
+ RefOffset = Op.getRawOperand(1);
+ }
+ auto RefDie = Unit.getOrigUnit().getDIEForOffset(RefOffset);
+ uint32_t RefIdx = Unit.getOrigUnit().getDIEIndex(RefDie);
+ CompileUnit::DIEInfo &Info = Unit.getInfo(RefIdx);
+ uint32_t Offset = 0;
+ if (DIE *Clone = Info.Clone)
+ Offset = Clone->getOffset();
+ else
+ Linker.reportWarning("base type ref doesn't point to DW_TAG_base_type.",
+ OF);
+ uint8_t ULEB[16];
+ unsigned RealSize = encodeULEB128(Offset, ULEB, ULEBsize);
+ if (RealSize > ULEBsize) {
+ // Emit the generic type as a fallback.
+ RealSize = encodeULEB128(0, ULEB, ULEBsize);
+ Linker.reportWarning("base type ref doesn't fit.", OF);
+ }
+ assert(RealSize == ULEBsize && "padding failed");
+ ArrayRef<uint8_t> ULEBbytes(ULEB, ULEBsize);
+ OutputBuffer.append(ULEBbytes.begin(), ULEBbytes.end());
+ } else {
+ // Copy over everything else unmodified.
+ StringRef Bytes = Data.getData().slice(OpOffset, Op.getEndOffset());
+ OutputBuffer.append(Bytes.begin(), Bytes.end());
+ }
+ OpOffset = Op.getEndOffset();
+ }
+}
+
+unsigned DWARFLinker::DIECloner::cloneBlockAttribute(
+ DIE &Die, const DwarfLinkerObjFile &OF, CompileUnit &Unit,
+ AttributeSpec AttrSpec, const DWARFFormValue &Val, unsigned AttrSize,
+ bool IsLittleEndian) {
+ DIEValueList *Attr;
+ DIEValue Value;
+ DIELoc *Loc = nullptr;
+ DIEBlock *Block = nullptr;
+ if (AttrSpec.Form == dwarf::DW_FORM_exprloc) {
+ Loc = new (DIEAlloc) DIELoc;
+ Linker.DIELocs.push_back(Loc);
+ } else {
+ Block = new (DIEAlloc) DIEBlock;
+ Linker.DIEBlocks.push_back(Block);
+ }
+ Attr = Loc ? static_cast<DIEValueList *>(Loc)
+ : static_cast<DIEValueList *>(Block);
+
+ if (Loc)
+ Value = DIEValue(dwarf::Attribute(AttrSpec.Attr),
+ dwarf::Form(AttrSpec.Form), Loc);
+ else
+ Value = DIEValue(dwarf::Attribute(AttrSpec.Attr),
+ dwarf::Form(AttrSpec.Form), Block);
+
+ // If the block is a DWARF Expression, clone it into the temporary
+ // buffer using cloneExpression(), otherwise copy the data directly.
+ SmallVector<uint8_t, 32> Buffer;
+ ArrayRef<uint8_t> Bytes = *Val.getAsBlock();
+ if (DWARFAttribute::mayHaveLocationDescription(AttrSpec.Attr) &&
+ (Val.isFormClass(DWARFFormValue::FC_Block) ||
+ Val.isFormClass(DWARFFormValue::FC_Exprloc))) {
+ DWARFUnit &OrigUnit = Unit.getOrigUnit();
+ DataExtractor Data(StringRef((const char *)Bytes.data(), Bytes.size()),
+ IsLittleEndian, OrigUnit.getAddressByteSize());
+ DWARFExpression Expr(Data, OrigUnit.getVersion(),
+ OrigUnit.getAddressByteSize());
+ cloneExpression(Data, Expr, OF, Unit, Buffer);
+ Bytes = Buffer;
+ }
+ for (auto Byte : Bytes)
+ Attr->addValue(DIEAlloc, static_cast<dwarf::Attribute>(0),
+ dwarf::DW_FORM_data1, DIEInteger(Byte));
+
+ // FIXME: If DIEBlock and DIELoc just reuses the Size field of
+ // the DIE class, this "if" could be replaced by
+ // Attr->setSize(Bytes.size()).
+ if (Loc)
+ Loc->setSize(Bytes.size());
+ else
+ Block->setSize(Bytes.size());
+
+ Die.addValue(DIEAlloc, Value);
+ return AttrSize;
+}
+
+unsigned DWARFLinker::DIECloner::cloneAddressAttribute(
+ DIE &Die, AttributeSpec AttrSpec, const DWARFFormValue &Val,
+ const CompileUnit &Unit, AttributesInfo &Info) {
+ uint64_t Addr = *Val.getAsAddress();
+
+ if (LLVM_UNLIKELY(Linker.Options.Update)) {
+ if (AttrSpec.Attr == dwarf::DW_AT_low_pc)
+ Info.HasLowPc = true;
+ Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
+ dwarf::Form(AttrSpec.Form), DIEInteger(Addr));
+ return Unit.getOrigUnit().getAddressByteSize();
+ }
+
+ if (AttrSpec.Attr == dwarf::DW_AT_low_pc) {
+ if (Die.getTag() == dwarf::DW_TAG_inlined_subroutine ||
+ Die.getTag() == dwarf::DW_TAG_lexical_block)
+ // The low_pc of a block or inline subroutine might get
+ // relocated because it happens to match the low_pc of the
+ // enclosing subprogram. To prevent issues with that, always use
+ // the low_pc from the input DIE if relocations have been applied.
+ Addr = (Info.OrigLowPc != std::numeric_limits<uint64_t>::max()
+ ? Info.OrigLowPc
+ : Addr) +
+ Info.PCOffset;
+ else if (Die.getTag() == dwarf::DW_TAG_compile_unit) {
+ Addr = Unit.getLowPc();
+ if (Addr == std::numeric_limits<uint64_t>::max())
+ return 0;
+ }
+ Info.HasLowPc = true;
+ } else if (AttrSpec.Attr == dwarf::DW_AT_high_pc) {
+ if (Die.getTag() == dwarf::DW_TAG_compile_unit) {
+ if (uint64_t HighPc = Unit.getHighPc())
+ Addr = HighPc;
+ else
+ return 0;
+ } else
+ // If we have a high_pc recorded for the input DIE, use
+ // it. Otherwise (when no relocations where applied) just use the
+ // one we just decoded.
+ Addr = (Info.OrigHighPc ? Info.OrigHighPc : Addr) + Info.PCOffset;
+ } else if (AttrSpec.Attr == dwarf::DW_AT_call_return_pc) {
+ // Relocate a return PC address within a call site entry.
+ if (Die.getTag() == dwarf::DW_TAG_call_site)
+ Addr += Info.PCOffset;
+ }
+
+ Die.addValue(DIEAlloc, static_cast<dwarf::Attribute>(AttrSpec.Attr),
+ static_cast<dwarf::Form>(AttrSpec.Form), DIEInteger(Addr));
+ return Unit.getOrigUnit().getAddressByteSize();
+}
+
+unsigned DWARFLinker::DIECloner::cloneScalarAttribute(
+ DIE &Die, const DWARFDie &InputDIE, const DwarfLinkerObjFile &OF,
+ CompileUnit &Unit, AttributeSpec AttrSpec, const DWARFFormValue &Val,
+ unsigned AttrSize, AttributesInfo &Info) {
+ uint64_t Value;
+
+ if (LLVM_UNLIKELY(Linker.Options.Update)) {
+ if (auto OptionalValue = Val.getAsUnsignedConstant())
+ Value = *OptionalValue;
+ else if (auto OptionalValue = Val.getAsSignedConstant())
+ Value = *OptionalValue;
+ else if (auto OptionalValue = Val.getAsSectionOffset())
+ Value = *OptionalValue;
+ else {
+ Linker.reportWarning(
+ "Unsupported scalar attribute form. Dropping attribute.", OF,
+ &InputDIE);
+ return 0;
+ }
+ if (AttrSpec.Attr == dwarf::DW_AT_declaration && Value)
+ Info.IsDeclaration = true;
+ Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
+ dwarf::Form(AttrSpec.Form), DIEInteger(Value));
+ return AttrSize;
+ }
+
+ if (AttrSpec.Attr == dwarf::DW_AT_high_pc &&
+ Die.getTag() == dwarf::DW_TAG_compile_unit) {
+ if (Unit.getLowPc() == -1ULL)
+ return 0;
+ // Dwarf >= 4 high_pc is an size, not an address.
+ Value = Unit.getHighPc() - Unit.getLowPc();
+ } else if (AttrSpec.Form == dwarf::DW_FORM_sec_offset)
+ Value = *Val.getAsSectionOffset();
+ else if (AttrSpec.Form == dwarf::DW_FORM_sdata)
+ Value = *Val.getAsSignedConstant();
+ else if (auto OptionalValue = Val.getAsUnsignedConstant())
+ Value = *OptionalValue;
+ else {
+ Linker.reportWarning(
+ "Unsupported scalar attribute form. Dropping attribute.", OF,
+ &InputDIE);
+ return 0;
+ }
+ PatchLocation Patch =
+ Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
+ dwarf::Form(AttrSpec.Form), DIEInteger(Value));
+ if (AttrSpec.Attr == dwarf::DW_AT_ranges) {
+ Unit.noteRangeAttribute(Die, Patch);
+ Info.HasRanges = true;
+ }
+
+ // A more generic way to check for location attributes would be
+ // nice, but it's very unlikely that any other attribute needs a
+ // location list.
+ // FIXME: use DWARFAttribute::mayHaveLocationDescription().
+ else if (AttrSpec.Attr == dwarf::DW_AT_location ||
+ AttrSpec.Attr == dwarf::DW_AT_frame_base) {
+ Unit.noteLocationAttribute(Patch, Info.PCOffset);
+ } else if (AttrSpec.Attr == dwarf::DW_AT_declaration && Value)
+ Info.IsDeclaration = true;
+
+ return AttrSize;
+}
+
+/// Clone \p InputDIE's attribute described by \p AttrSpec with
+/// value \p Val, and add it to \p Die.
+/// \returns the size of the cloned attribute.
+unsigned DWARFLinker::DIECloner::cloneAttribute(
+ DIE &Die, const DWARFDie &InputDIE, const DwarfLinkerObjFile &OF,
+ CompileUnit &Unit, OffsetsStringPool &StringPool, const DWARFFormValue &Val,
+ const AttributeSpec AttrSpec, unsigned AttrSize, AttributesInfo &Info,
+ bool IsLittleEndian) {
+ const DWARFUnit &U = Unit.getOrigUnit();
+
+ switch (AttrSpec.Form) {
+ case dwarf::DW_FORM_strp:
+ case dwarf::DW_FORM_string:
+ return cloneStringAttribute(Die, AttrSpec, Val, U, StringPool, Info);
+ case dwarf::DW_FORM_ref_addr:
+ case dwarf::DW_FORM_ref1:
+ case dwarf::DW_FORM_ref2:
+ case dwarf::DW_FORM_ref4:
+ case dwarf::DW_FORM_ref8:
+ return cloneDieReferenceAttribute(Die, InputDIE, AttrSpec, AttrSize, Val,
+ OF, Unit);
+ case dwarf::DW_FORM_block:
+ case dwarf::DW_FORM_block1:
+ case dwarf::DW_FORM_block2:
+ case dwarf::DW_FORM_block4:
+ case dwarf::DW_FORM_exprloc:
+ return cloneBlockAttribute(Die, OF, Unit, AttrSpec, Val, AttrSize,
+ IsLittleEndian);
+ case dwarf::DW_FORM_addr:
+ return cloneAddressAttribute(Die, AttrSpec, Val, Unit, Info);
+ case dwarf::DW_FORM_data1:
+ case dwarf::DW_FORM_data2:
+ case dwarf::DW_FORM_data4:
+ case dwarf::DW_FORM_data8:
+ case dwarf::DW_FORM_udata:
+ case dwarf::DW_FORM_sdata:
+ case dwarf::DW_FORM_sec_offset:
+ case dwarf::DW_FORM_flag:
+ case dwarf::DW_FORM_flag_present:
+ return cloneScalarAttribute(Die, InputDIE, OF, Unit, AttrSpec, Val,
+ AttrSize, Info);
+ default:
+ Linker.reportWarning(
+ "Unsupported attribute form in cloneAttribute. Dropping.", OF,
+ &InputDIE);
+ }
+
+ return 0;
+}
+
+static bool isObjCSelector(StringRef Name) {
+ return Name.size() > 2 && (Name[0] == '-' || Name[0] == '+') &&
+ (Name[1] == '[');
+}
+
+void DWARFLinker::DIECloner::addObjCAccelerator(CompileUnit &Unit,
+ const DIE *Die,
+ DwarfStringPoolEntryRef Name,
+ OffsetsStringPool &StringPool,
+ bool SkipPubSection) {
+ assert(isObjCSelector(Name.getString()) && "not an objc selector");
+ // Objective C method or class function.
+ // "- [Class(Category) selector :withArg ...]"
+ StringRef ClassNameStart(Name.getString().drop_front(2));
+ size_t FirstSpace = ClassNameStart.find(' ');
+ if (FirstSpace == StringRef::npos)
+ return;
+
+ StringRef SelectorStart(ClassNameStart.data() + FirstSpace + 1);
+ if (!SelectorStart.size())
+ return;
+
+ StringRef Selector(SelectorStart.data(), SelectorStart.size() - 1);
+ Unit.addNameAccelerator(Die, StringPool.getEntry(Selector), SkipPubSection);
+
+ // Add an entry for the class name that points to this
+ // method/class function.
+ StringRef ClassName(ClassNameStart.data(), FirstSpace);
+ Unit.addObjCAccelerator(Die, StringPool.getEntry(ClassName), SkipPubSection);
+
+ if (ClassName[ClassName.size() - 1] == ')') {
+ size_t OpenParens = ClassName.find('(');
+ if (OpenParens != StringRef::npos) {
+ StringRef ClassNameNoCategory(ClassName.data(), OpenParens);
+ Unit.addObjCAccelerator(Die, StringPool.getEntry(ClassNameNoCategory),
+ SkipPubSection);
+
+ std::string MethodNameNoCategory(Name.getString().data(), OpenParens + 2);
+ // FIXME: The missing space here may be a bug, but
+ // dsymutil-classic also does it this way.
+ MethodNameNoCategory.append(SelectorStart);
+ Unit.addNameAccelerator(Die, StringPool.getEntry(MethodNameNoCategory),
+ SkipPubSection);
+ }
+ }
+}
+
+static bool
+shouldSkipAttribute(DWARFAbbreviationDeclaration::AttributeSpec AttrSpec,
+ uint16_t Tag, bool InDebugMap, bool SkipPC,
+ bool InFunctionScope) {
+ switch (AttrSpec.Attr) {
+ default:
+ return false;
+ case dwarf::DW_AT_low_pc:
+ case dwarf::DW_AT_high_pc:
+ case dwarf::DW_AT_ranges:
+ return SkipPC;
+ case dwarf::DW_AT_location:
+ case dwarf::DW_AT_frame_base:
+ // FIXME: for some reason dsymutil-classic keeps the location attributes
+ // when they are of block type (i.e. not location lists). This is totally
+ // wrong for globals where we will keep a wrong address. It is mostly
+ // harmless for locals, but there is no point in keeping these anyway when
+ // the function wasn't linked.
+ return (SkipPC || (!InFunctionScope && Tag == dwarf::DW_TAG_variable &&
+ !InDebugMap)) &&
+ !DWARFFormValue(AttrSpec.Form).isFormClass(DWARFFormValue::FC_Block);
+ }
+}
+
+DIE *DWARFLinker::DIECloner::cloneDIE(
+ const DWARFDie &InputDIE, const DwarfLinkerObjFile &OF, CompileUnit &Unit,
+ OffsetsStringPool &StringPool, int64_t PCOffset, uint32_t OutOffset,
+ unsigned Flags, bool IsLittleEndian, DIE *Die) {
+ DWARFUnit &U = Unit.getOrigUnit();
+ unsigned Idx = U.getDIEIndex(InputDIE);
+ CompileUnit::DIEInfo &Info = Unit.getInfo(Idx);
+
+ // Should the DIE appear in the output?
+ if (!Unit.getInfo(Idx).Keep)
+ return nullptr;
+
+ uint64_t Offset = InputDIE.getOffset();
+ assert(!(Die && Info.Clone) && "Can't supply a DIE and a cloned DIE");
+ if (!Die) {
+ // The DIE might have been already created by a forward reference
+ // (see cloneDieReferenceAttribute()).
+ if (!Info.Clone)
+ Info.Clone = DIE::get(DIEAlloc, dwarf::Tag(InputDIE.getTag()));
+ Die = Info.Clone;
+ }
+
+ assert(Die->getTag() == InputDIE.getTag());
+ Die->setOffset(OutOffset);
+ if ((Unit.hasODR() || Unit.isClangModule()) && !Info.Incomplete &&
+ Die->getTag() != dwarf::DW_TAG_namespace && Info.Ctxt &&
+ Info.Ctxt != Unit.getInfo(Info.ParentIdx).Ctxt &&
+ !Info.Ctxt->getCanonicalDIEOffset()) {
+ // We are about to emit a DIE that is the root of its own valid
+ // DeclContext tree. Make the current offset the canonical offset
+ // for this context.
+ Info.Ctxt->setCanonicalDIEOffset(OutOffset + Unit.getStartOffset());
+ }
+
+ // Extract and clone every attribute.
+ DWARFDataExtractor Data = U.getDebugInfoExtractor();
+ // Point to the next DIE (generally there is always at least a NULL
+ // entry after the current one). If this is a lone
+ // DW_TAG_compile_unit without any children, point to the next unit.
+ uint64_t NextOffset = (Idx + 1 < U.getNumDIEs())
+ ? U.getDIEAtIndex(Idx + 1).getOffset()
+ : U.getNextUnitOffset();
+ AttributesInfo AttrInfo;
+
+ // We could copy the data only if we need to apply a relocation to it. After
+ // testing, it seems there is no performance downside to doing the copy
+ // unconditionally, and it makes the code simpler.
+ SmallString<40> DIECopy(Data.getData().substr(Offset, NextOffset - Offset));
+ Data =
+ DWARFDataExtractor(DIECopy, Data.isLittleEndian(), Data.getAddressSize());
+
+ // Modify the copy with relocated addresses.
+ if (ObjFile.Addresses->areRelocationsResolved() &&
+ ObjFile.Addresses->applyValidRelocs(DIECopy, Offset,
+ Data.isLittleEndian())) {
+ // If we applied relocations, we store the value of high_pc that was
+ // potentially stored in the input DIE. If high_pc is an address
+ // (Dwarf version == 2), then it might have been relocated to a
+ // totally unrelated value (because the end address in the object
+ // file might be start address of another function which got moved
+ // independently by the linker). The computation of the actual
+ // high_pc value is done in cloneAddressAttribute().
+ AttrInfo.OrigHighPc =
+ dwarf::toAddress(InputDIE.find(dwarf::DW_AT_high_pc), 0);
+ // Also store the low_pc. It might get relocated in an
+ // inline_subprogram that happens at the beginning of its
+ // inlining function.
+ AttrInfo.OrigLowPc = dwarf::toAddress(InputDIE.find(dwarf::DW_AT_low_pc),
+ std::numeric_limits<uint64_t>::max());
+ }
+
+ // Reset the Offset to 0 as we will be working on the local copy of
+ // the data.
+ Offset = 0;
+
+ const auto *Abbrev = InputDIE.getAbbreviationDeclarationPtr();
+ Offset += getULEB128Size(Abbrev->getCode());
+
+ // We are entering a subprogram. Get and propagate the PCOffset.
+ if (Die->getTag() == dwarf::DW_TAG_subprogram)
+ PCOffset = Info.AddrAdjust;
+ AttrInfo.PCOffset = PCOffset;
+
+ if (Abbrev->getTag() == dwarf::DW_TAG_subprogram) {
+ Flags |= TF_InFunctionScope;
+ if (!Info.InDebugMap && LLVM_LIKELY(!Update))
+ Flags |= TF_SkipPC;
+ }
+
+ bool Copied = false;
+ for (const auto &AttrSpec : Abbrev->attributes()) {
+ if (LLVM_LIKELY(!Update) &&
+ shouldSkipAttribute(AttrSpec, Die->getTag(), Info.InDebugMap,
+ Flags & TF_SkipPC, Flags & TF_InFunctionScope)) {
+ DWARFFormValue::skipValue(AttrSpec.Form, Data, &Offset,
+ U.getFormParams());
+ // FIXME: dsymutil-classic keeps the old abbreviation around
+ // even if it's not used. We can remove this (and the copyAbbrev
+ // helper) as soon as bit-for-bit compatibility is not a goal anymore.
+ if (!Copied) {
+ copyAbbrev(*InputDIE.getAbbreviationDeclarationPtr(), Unit.hasODR());
+ Copied = true;
+ }
+ continue;
+ }
+
+ DWARFFormValue Val(AttrSpec.Form);
+ uint64_t AttrSize = Offset;
+ Val.extractValue(Data, &Offset, U.getFormParams(), &U);
+ AttrSize = Offset - AttrSize;
+
+ OutOffset += cloneAttribute(*Die, InputDIE, OF, Unit, StringPool, Val,
+ AttrSpec, AttrSize, AttrInfo, IsLittleEndian);
+ }
+
+ // Look for accelerator entries.
+ uint16_t Tag = InputDIE.getTag();
+ // FIXME: This is slightly wrong. An inline_subroutine without a
+ // low_pc, but with AT_ranges might be interesting to get into the
+ // accelerator tables too. For now stick with dsymutil's behavior.
+ if ((Info.InDebugMap || AttrInfo.HasLowPc || AttrInfo.HasRanges) &&
+ Tag != dwarf::DW_TAG_compile_unit &&
+ getDIENames(InputDIE, AttrInfo, StringPool,
+ Tag != dwarf::DW_TAG_inlined_subroutine)) {
+ if (AttrInfo.MangledName && AttrInfo.MangledName != AttrInfo.Name)
+ Unit.addNameAccelerator(Die, AttrInfo.MangledName,
+ Tag == dwarf::DW_TAG_inlined_subroutine);
+ if (AttrInfo.Name) {
+ if (AttrInfo.NameWithoutTemplate)
+ Unit.addNameAccelerator(Die, AttrInfo.NameWithoutTemplate,
+ /* SkipPubSection */ true);
+ Unit.addNameAccelerator(Die, AttrInfo.Name,
+ Tag == dwarf::DW_TAG_inlined_subroutine);
+ }
+ if (AttrInfo.Name && isObjCSelector(AttrInfo.Name.getString()))
+ addObjCAccelerator(Unit, Die, AttrInfo.Name, StringPool,
+ /* SkipPubSection =*/true);
+
+ } else if (Tag == dwarf::DW_TAG_namespace) {
+ if (!AttrInfo.Name)
+ AttrInfo.Name = StringPool.getEntry("(anonymous namespace)");
+ Unit.addNamespaceAccelerator(Die, AttrInfo.Name);
+ } else if (isTypeTag(Tag) && !AttrInfo.IsDeclaration &&
+ getDIENames(InputDIE, AttrInfo, StringPool) && AttrInfo.Name &&
+ AttrInfo.Name.getString()[0]) {
+ uint32_t Hash = hashFullyQualifiedName(InputDIE, Unit, OF);
+ uint64_t RuntimeLang =
+ dwarf::toUnsigned(InputDIE.find(dwarf::DW_AT_APPLE_runtime_class))
+ .getValueOr(0);
+ bool ObjCClassIsImplementation =
+ (RuntimeLang == dwarf::DW_LANG_ObjC ||
+ RuntimeLang == dwarf::DW_LANG_ObjC_plus_plus) &&
+ dwarf::toUnsigned(InputDIE.find(dwarf::DW_AT_APPLE_objc_complete_type))
+ .getValueOr(0);
+ Unit.addTypeAccelerator(Die, AttrInfo.Name, ObjCClassIsImplementation,
+ Hash);
+ }
+
+ // Determine whether there are any children that we want to keep.
+ bool HasChildren = false;
+ for (auto Child : InputDIE.children()) {
+ unsigned Idx = U.getDIEIndex(Child);
+ if (Unit.getInfo(Idx).Keep) {
+ HasChildren = true;
+ break;
+ }
+ }
+
+ DIEAbbrev NewAbbrev = Die->generateAbbrev();
+ if (HasChildren)
+ NewAbbrev.setChildrenFlag(dwarf::DW_CHILDREN_yes);
+ // Assign a permanent abbrev number
+ Linker.assignAbbrev(NewAbbrev);
+ Die->setAbbrevNumber(NewAbbrev.getNumber());
+
+ // Add the size of the abbreviation number to the output offset.
+ OutOffset += getULEB128Size(Die->getAbbrevNumber());
+
+ if (!HasChildren) {
+ // Update our size.
+ Die->setSize(OutOffset - Die->getOffset());
+ return Die;
+ }
+
+ // Recursively clone children.
+ for (auto Child : InputDIE.children()) {
+ if (DIE *Clone = cloneDIE(Child, OF, Unit, StringPool, PCOffset, OutOffset,
+ Flags, IsLittleEndian)) {
+ Die->addChild(Clone);
+ OutOffset = Clone->getOffset() + Clone->getSize();
+ }
+ }
+
+ // Account for the end of children marker.
+ OutOffset += sizeof(int8_t);
+ // Update our size.
+ Die->setSize(OutOffset - Die->getOffset());
+ return Die;
+}
+
+/// Patch the input object file relevant debug_ranges entries
+/// and emit them in the output file. Update the relevant attributes
+/// to point at the new entries.
+void DWARFLinker::patchRangesForUnit(const CompileUnit &Unit,
+ DWARFContext &OrigDwarf,
+ const DwarfLinkerObjFile &OF) const {
+ DWARFDebugRangeList RangeList;
+ const auto &FunctionRanges = Unit.getFunctionRanges();
+ unsigned AddressSize = Unit.getOrigUnit().getAddressByteSize();
+ DWARFDataExtractor RangeExtractor(OrigDwarf.getDWARFObj(),
+ OrigDwarf.getDWARFObj().getRangesSection(),
+ OrigDwarf.isLittleEndian(), AddressSize);
+ auto InvalidRange = FunctionRanges.end(), CurrRange = InvalidRange;
+ DWARFUnit &OrigUnit = Unit.getOrigUnit();
+ auto OrigUnitDie = OrigUnit.getUnitDIE(false);
+ uint64_t OrigLowPc =
+ dwarf::toAddress(OrigUnitDie.find(dwarf::DW_AT_low_pc), -1ULL);
+ // Ranges addresses are based on the unit's low_pc. Compute the
+ // offset we need to apply to adapt to the new unit's low_pc.
+ int64_t UnitPcOffset = 0;
+ if (OrigLowPc != -1ULL)
+ UnitPcOffset = int64_t(OrigLowPc) - Unit.getLowPc();
+
+ for (const auto &RangeAttribute : Unit.getRangesAttributes()) {
+ uint64_t Offset = RangeAttribute.get();
+ RangeAttribute.set(DwarfEmitter->getRangesSectionSize());
+ if (Error E = RangeList.extract(RangeExtractor, &Offset)) {
+ llvm::consumeError(std::move(E));
+ reportWarning("invalid range list ignored.", OF);
+ RangeList.clear();
+ }
+ const auto &Entries = RangeList.getEntries();
+ if (!Entries.empty()) {
+ const DWARFDebugRangeList::RangeListEntry &First = Entries.front();
+
+ if (CurrRange == InvalidRange ||
+ First.StartAddress + OrigLowPc < CurrRange.start() ||
+ First.StartAddress + OrigLowPc >= CurrRange.stop()) {
+ CurrRange = FunctionRanges.find(First.StartAddress + OrigLowPc);
+ if (CurrRange == InvalidRange ||
+ CurrRange.start() > First.StartAddress + OrigLowPc) {
+ reportWarning("no mapping for range.", OF);
+ continue;
+ }
+ }
+ }
+
+ DwarfEmitter->emitRangesEntries(UnitPcOffset, OrigLowPc, CurrRange, Entries,
+ AddressSize);
+ }
+}
+
+/// Generate the debug_aranges entries for \p Unit and if the
+/// unit has a DW_AT_ranges attribute, also emit the debug_ranges
+/// contribution for this attribute.
+/// FIXME: this could actually be done right in patchRangesForUnit,
+/// but for the sake of initial bit-for-bit compatibility with legacy
+/// dsymutil, we have to do it in a delayed pass.
+void DWARFLinker::generateUnitRanges(CompileUnit &Unit) const {
+ auto Attr = Unit.getUnitRangesAttribute();
+ if (Attr)
+ Attr->set(DwarfEmitter->getRangesSectionSize());
+ DwarfEmitter->emitUnitRangesEntries(Unit, static_cast<bool>(Attr));
+}
+
+/// Insert the new line info sequence \p Seq into the current
+/// set of already linked line info \p Rows.
+static void insertLineSequence(std::vector<DWARFDebugLine::Row> &Seq,
+ std::vector<DWARFDebugLine::Row> &Rows) {
+ if (Seq.empty())
+ return;
+
+ if (!Rows.empty() && Rows.back().Address < Seq.front().Address) {
+ Rows.insert(Rows.end(), Seq.begin(), Seq.end());
+ Seq.clear();
+ return;
+ }
+
+ object::SectionedAddress Front = Seq.front().Address;
+ auto InsertPoint = partition_point(
+ Rows, [=](const DWARFDebugLine::Row &O) { return O.Address < Front; });
+
+ // FIXME: this only removes the unneeded end_sequence if the
+ // sequences have been inserted in order. Using a global sort like
+ // described in patchLineTableForUnit() and delaying the end_sequene
+ // elimination to emitLineTableForUnit() we can get rid of all of them.
+ if (InsertPoint != Rows.end() && InsertPoint->Address == Front &&
+ InsertPoint->EndSequence) {
+ *InsertPoint = Seq.front();
+ Rows.insert(InsertPoint + 1, Seq.begin() + 1, Seq.end());
+ } else {
+ Rows.insert(InsertPoint, Seq.begin(), Seq.end());
+ }
+
+ Seq.clear();
+}
+
+static void patchStmtList(DIE &Die, DIEInteger Offset) {
+ for (auto &V : Die.values())
+ if (V.getAttribute() == dwarf::DW_AT_stmt_list) {
+ V = DIEValue(V.getAttribute(), V.getForm(), Offset);
+ return;
+ }
+
+ llvm_unreachable("Didn't find DW_AT_stmt_list in cloned DIE!");
+}
+
+/// Extract the line table for \p Unit from \p OrigDwarf, and
+/// recreate a relocated version of these for the address ranges that
+/// are present in the binary.
+void DWARFLinker::patchLineTableForUnit(CompileUnit &Unit,
+ DWARFContext &OrigDwarf,
+ const DwarfLinkerObjFile &OF) {
+ DWARFDie CUDie = Unit.getOrigUnit().getUnitDIE();
+ auto StmtList = dwarf::toSectionOffset(CUDie.find(dwarf::DW_AT_stmt_list));
+ if (!StmtList)
+ return;
+
+ // Update the cloned DW_AT_stmt_list with the correct debug_line offset.
+ if (auto *OutputDIE = Unit.getOutputUnitDIE())
+ patchStmtList(*OutputDIE, DIEInteger(DwarfEmitter->getLineSectionSize()));
+
+ RangesTy &Ranges = OF.Addresses->getValidAddressRanges();
+
+ // Parse the original line info for the unit.
+ DWARFDebugLine::LineTable LineTable;
+ uint64_t StmtOffset = *StmtList;
+ DWARFDataExtractor LineExtractor(
+ OrigDwarf.getDWARFObj(), OrigDwarf.getDWARFObj().getLineSection(),
+ OrigDwarf.isLittleEndian(), Unit.getOrigUnit().getAddressByteSize());
+ if (needToTranslateStrings())
+ return DwarfEmitter->translateLineTable(LineExtractor, StmtOffset);
+
+ Error Err = LineTable.parse(LineExtractor, &StmtOffset, OrigDwarf,
+ &Unit.getOrigUnit(), DWARFContext::dumpWarning);
+ DWARFContext::dumpWarning(std::move(Err));
+
+ // This vector is the output line table.
+ std::vector<DWARFDebugLine::Row> NewRows;
+ NewRows.reserve(LineTable.Rows.size());
+
+ // Current sequence of rows being extracted, before being inserted
+ // in NewRows.
+ std::vector<DWARFDebugLine::Row> Seq;
+ const auto &FunctionRanges = Unit.getFunctionRanges();
+ auto InvalidRange = FunctionRanges.end(), CurrRange = InvalidRange;
+
+ // FIXME: This logic is meant to generate exactly the same output as
+ // Darwin's classic dsymutil. There is a nicer way to implement this
+ // by simply putting all the relocated line info in NewRows and simply
+ // sorting NewRows before passing it to emitLineTableForUnit. This
+ // should be correct as sequences for a function should stay
+ // together in the sorted output. There are a few corner cases that
+ // look suspicious though, and that required to implement the logic
+ // this way. Revisit that once initial validation is finished.
+
+ // Iterate over the object file line info and extract the sequences
+ // that correspond to linked functions.
+ for (auto &Row : LineTable.Rows) {
+ // Check whether we stepped out of the range. The range is
+ // half-open, but consider accept the end address of the range if
+ // it is marked as end_sequence in the input (because in that
+ // case, the relocation offset is accurate and that entry won't
+ // serve as the start of another function).
+ if (CurrRange == InvalidRange || Row.Address.Address < CurrRange.start() ||
+ Row.Address.Address > CurrRange.stop() ||
+ (Row.Address.Address == CurrRange.stop() && !Row.EndSequence)) {
+ // We just stepped out of a known range. Insert a end_sequence
+ // corresponding to the end of the range.
+ uint64_t StopAddress = CurrRange != InvalidRange
+ ? CurrRange.stop() + CurrRange.value()
+ : -1ULL;
+ CurrRange = FunctionRanges.find(Row.Address.Address);
+ bool CurrRangeValid =
+ CurrRange != InvalidRange && CurrRange.start() <= Row.Address.Address;
+ if (!CurrRangeValid) {
+ CurrRange = InvalidRange;
+ if (StopAddress != -1ULL) {
+ // Try harder by looking in the Address ranges map.
+ // There are corner cases where this finds a
+ // valid entry. It's unclear if this is right or wrong, but
+ // for now do as dsymutil.
+ // FIXME: Understand exactly what cases this addresses and
+ // potentially remove it along with the Ranges map.
+ auto Range = Ranges.lower_bound(Row.Address.Address);
+ if (Range != Ranges.begin() && Range != Ranges.end())
+ --Range;
+
+ if (Range != Ranges.end() && Range->first <= Row.Address.Address &&
+ Range->second.HighPC >= Row.Address.Address) {
+ StopAddress = Row.Address.Address + Range->second.Offset;
+ }
+ }
+ }
+ if (StopAddress != -1ULL && !Seq.empty()) {
+ // Insert end sequence row with the computed end address, but
+ // the same line as the previous one.
+ auto NextLine = Seq.back();
+ NextLine.Address.Address = StopAddress;
+ NextLine.EndSequence = 1;
+ NextLine.PrologueEnd = 0;
+ NextLine.BasicBlock = 0;
+ NextLine.EpilogueBegin = 0;
+ Seq.push_back(NextLine);
+ insertLineSequence(Seq, NewRows);
+ }
+
+ if (!CurrRangeValid)
+ continue;
+ }
+
+ // Ignore empty sequences.
+ if (Row.EndSequence && Seq.empty())
+ continue;
+
+ // Relocate row address and add it to the current sequence.
+ Row.Address.Address += CurrRange.value();
+ Seq.emplace_back(Row);
+
+ if (Row.EndSequence)
+ insertLineSequence(Seq, NewRows);
+ }
+
+ // Finished extracting, now emit the line tables.
+ // FIXME: LLVM hard-codes its prologue values. We just copy the
+ // prologue over and that works because we act as both producer and
+ // consumer. It would be nicer to have a real configurable line
+ // table emitter.
+ if (LineTable.Prologue.getVersion() < 2 ||
+ LineTable.Prologue.getVersion() > 5 ||
+ LineTable.Prologue.DefaultIsStmt != DWARF2_LINE_DEFAULT_IS_STMT ||
+ LineTable.Prologue.OpcodeBase > 13)
+ reportWarning("line table parameters mismatch. Cannot emit.", OF);
+ else {
+ uint32_t PrologueEnd = *StmtList + 10 + LineTable.Prologue.PrologueLength;
+ // DWARF v5 has an extra 2 bytes of information before the header_length
+ // field.
+ if (LineTable.Prologue.getVersion() == 5)
+ PrologueEnd += 2;
+ StringRef LineData = OrigDwarf.getDWARFObj().getLineSection().Data;
+ MCDwarfLineTableParams Params;
+ Params.DWARF2LineOpcodeBase = LineTable.Prologue.OpcodeBase;
+ Params.DWARF2LineBase = LineTable.Prologue.LineBase;
+ Params.DWARF2LineRange = LineTable.Prologue.LineRange;
+ DwarfEmitter->emitLineTableForUnit(
+ Params, LineData.slice(*StmtList + 4, PrologueEnd),
+ LineTable.Prologue.MinInstLength, NewRows,
+ Unit.getOrigUnit().getAddressByteSize());
+ }
+}
+
+void DWARFLinker::emitAcceleratorEntriesForUnit(CompileUnit &Unit) {
+ switch (Options.TheAccelTableKind) {
+ case AccelTableKind::Apple:
+ emitAppleAcceleratorEntriesForUnit(Unit);
+ break;
+ case AccelTableKind::Dwarf:
+ emitDwarfAcceleratorEntriesForUnit(Unit);
+ break;
+ case AccelTableKind::Default:
+ llvm_unreachable("The default must be updated to a concrete value.");
+ break;
+ }
+}
+
+void DWARFLinker::emitAppleAcceleratorEntriesForUnit(CompileUnit &Unit) {
+ // Add namespaces.
+ for (const auto &Namespace : Unit.getNamespaces())
+ AppleNamespaces.addName(Namespace.Name,
+ Namespace.Die->getOffset() + Unit.getStartOffset());
+
+ /// Add names.
+ DwarfEmitter->emitPubNamesForUnit(Unit);
+ for (const auto &Pubname : Unit.getPubnames())
+ AppleNames.addName(Pubname.Name,
+ Pubname.Die->getOffset() + Unit.getStartOffset());
+
+ /// Add types.
+ DwarfEmitter->emitPubTypesForUnit(Unit);
+ for (const auto &Pubtype : Unit.getPubtypes())
+ AppleTypes.addName(
+ Pubtype.Name, Pubtype.Die->getOffset() + Unit.getStartOffset(),
+ Pubtype.Die->getTag(),
+ Pubtype.ObjcClassImplementation ? dwarf::DW_FLAG_type_implementation
+ : 0,
+ Pubtype.QualifiedNameHash);
+
+ /// Add ObjC names.
+ for (const auto &ObjC : Unit.getObjC())
+ AppleObjc.addName(ObjC.Name, ObjC.Die->getOffset() + Unit.getStartOffset());
+}
+
+void DWARFLinker::emitDwarfAcceleratorEntriesForUnit(CompileUnit &Unit) {
+ for (const auto &Namespace : Unit.getNamespaces())
+ DebugNames.addName(Namespace.Name, Namespace.Die->getOffset(),
+ Namespace.Die->getTag(), Unit.getUniqueID());
+ for (const auto &Pubname : Unit.getPubnames())
+ DebugNames.addName(Pubname.Name, Pubname.Die->getOffset(),
+ Pubname.Die->getTag(), Unit.getUniqueID());
+ for (const auto &Pubtype : Unit.getPubtypes())
+ DebugNames.addName(Pubtype.Name, Pubtype.Die->getOffset(),
+ Pubtype.Die->getTag(), Unit.getUniqueID());
+}
+
+/// Read the frame info stored in the object, and emit the
+/// patched frame descriptions for the resulting file.
+///
+/// This is actually pretty easy as the data of the CIEs and FDEs can
+/// be considered as black boxes and moved as is. The only thing to do
+/// is to patch the addresses in the headers.
+void DWARFLinker::patchFrameInfoForObject(const DwarfLinkerObjFile &OF,
+ RangesTy &Ranges,
+ DWARFContext &OrigDwarf,
+ unsigned AddrSize) {
+ StringRef FrameData = OrigDwarf.getDWARFObj().getFrameSection().Data;
+ if (FrameData.empty())
+ return;
+
+ DataExtractor Data(FrameData, OrigDwarf.isLittleEndian(), 0);
+ uint64_t InputOffset = 0;
+
+ // Store the data of the CIEs defined in this object, keyed by their
+ // offsets.
+ DenseMap<uint64_t, StringRef> LocalCIES;
+
+ while (Data.isValidOffset(InputOffset)) {
+ uint64_t EntryOffset = InputOffset;
+ uint32_t InitialLength = Data.getU32(&InputOffset);
+ if (InitialLength == 0xFFFFFFFF)
+ return reportWarning("Dwarf64 bits no supported", OF);
+
+ uint32_t CIEId = Data.getU32(&InputOffset);
+ if (CIEId == 0xFFFFFFFF) {
+ // This is a CIE, store it.
+ StringRef CIEData = FrameData.substr(EntryOffset, InitialLength + 4);
+ LocalCIES[EntryOffset] = CIEData;
+ // The -4 is to account for the CIEId we just read.
+ InputOffset += InitialLength - 4;
+ continue;
+ }
+
+ uint32_t Loc = Data.getUnsigned(&InputOffset, AddrSize);
+
+ // Some compilers seem to emit frame info that doesn't start at
+ // the function entry point, thus we can't just lookup the address
+ // in the debug map. Use the AddressInfo's range map to see if the FDE
+ // describes something that we can relocate.
+ auto Range = Ranges.upper_bound(Loc);
+ if (Range != Ranges.begin())
+ --Range;
+ if (Range == Ranges.end() || Range->first > Loc ||
+ Range->second.HighPC <= Loc) {
+ // The +4 is to account for the size of the InitialLength field itself.
+ InputOffset = EntryOffset + InitialLength + 4;
+ continue;
+ }
+
+ // This is an FDE, and we have a mapping.
+ // Have we already emitted a corresponding CIE?
+ StringRef CIEData = LocalCIES[CIEId];
+ if (CIEData.empty())
+ return reportWarning("Inconsistent debug_frame content. Dropping.", OF);
+
+ // Look if we already emitted a CIE that corresponds to the
+ // referenced one (the CIE data is the key of that lookup).
+ auto IteratorInserted = EmittedCIEs.insert(
+ std::make_pair(CIEData, DwarfEmitter->getFrameSectionSize()));
+ // If there is no CIE yet for this ID, emit it.
+ if (IteratorInserted.second ||
+ // FIXME: dsymutil-classic only caches the last used CIE for
+ // reuse. Mimic that behavior for now. Just removing that
+ // second half of the condition and the LastCIEOffset variable
+ // makes the code DTRT.
+ LastCIEOffset != IteratorInserted.first->getValue()) {
+ LastCIEOffset = DwarfEmitter->getFrameSectionSize();
+ IteratorInserted.first->getValue() = LastCIEOffset;
+ DwarfEmitter->emitCIE(CIEData);
+ }
+
+ // Emit the FDE with updated address and CIE pointer.
+ // (4 + AddrSize) is the size of the CIEId + initial_location
+ // fields that will get reconstructed by emitFDE().
+ unsigned FDERemainingBytes = InitialLength - (4 + AddrSize);
+ DwarfEmitter->emitFDE(IteratorInserted.first->getValue(), AddrSize,
+ Loc + Range->second.Offset,
+ FrameData.substr(InputOffset, FDERemainingBytes));
+ InputOffset += FDERemainingBytes;
+ }
+}
+
+void DWARFLinker::DIECloner::copyAbbrev(
+ const DWARFAbbreviationDeclaration &Abbrev, bool HasODR) {
+ DIEAbbrev Copy(dwarf::Tag(Abbrev.getTag()),
+ dwarf::Form(Abbrev.hasChildren()));
+
+ for (const auto &Attr : Abbrev.attributes()) {
+ uint16_t Form = Attr.Form;
+ if (HasODR && isODRAttribute(Attr.Attr))
+ Form = dwarf::DW_FORM_ref_addr;
+ Copy.AddAttribute(dwarf::Attribute(Attr.Attr), dwarf::Form(Form));
+ }
+
+ Linker.assignAbbrev(Copy);
+}
+
+uint32_t
+DWARFLinker::DIECloner::hashFullyQualifiedName(DWARFDie DIE, CompileUnit &U,
+ const DwarfLinkerObjFile &OF,
+ int ChildRecurseDepth) {
+ const char *Name = nullptr;
+ DWARFUnit *OrigUnit = &U.getOrigUnit();
+ CompileUnit *CU = &U;
+ Optional<DWARFFormValue> Ref;
+
+ while (1) {
+ if (const char *CurrentName = DIE.getName(DINameKind::ShortName))
+ Name = CurrentName;
+
+ if (!(Ref = DIE.find(dwarf::DW_AT_specification)) &&
+ !(Ref = DIE.find(dwarf::DW_AT_abstract_origin)))
+ break;
+
+ if (!Ref->isFormClass(DWARFFormValue::FC_Reference))
+ break;
+
+ CompileUnit *RefCU;
+ if (auto RefDIE =
+ Linker.resolveDIEReference(OF, CompileUnits, *Ref, DIE, RefCU)) {
+ CU = RefCU;
+ OrigUnit = &RefCU->getOrigUnit();
+ DIE = RefDIE;
+ }
+ }
+
+ unsigned Idx = OrigUnit->getDIEIndex(DIE);
+ if (!Name && DIE.getTag() == dwarf::DW_TAG_namespace)
+ Name = "(anonymous namespace)";
+
+ if (CU->getInfo(Idx).ParentIdx == 0 ||
+ // FIXME: dsymutil-classic compatibility. Ignore modules.
+ CU->getOrigUnit().getDIEAtIndex(CU->getInfo(Idx).ParentIdx).getTag() ==
+ dwarf::DW_TAG_module)
+ return djbHash(Name ? Name : "", djbHash(ChildRecurseDepth ? "" : "::"));
+
+ DWARFDie Die = OrigUnit->getDIEAtIndex(CU->getInfo(Idx).ParentIdx);
+ return djbHash(
+ (Name ? Name : ""),
+ djbHash((Name ? "::" : ""),
+ hashFullyQualifiedName(Die, *CU, OF, ++ChildRecurseDepth)));
+}
+
+static uint64_t getDwoId(const DWARFDie &CUDie, const DWARFUnit &Unit) {
+ auto DwoId = dwarf::toUnsigned(
+ CUDie.find({dwarf::DW_AT_dwo_id, dwarf::DW_AT_GNU_dwo_id}));
+ if (DwoId)
+ return *DwoId;
+ return 0;
+}
+
+bool DWARFLinker::registerModuleReference(
+ DWARFDie CUDie, const DWARFUnit &Unit, const DwarfLinkerObjFile &OF,
+ OffsetsStringPool &StringPool, UniquingStringPool &UniquingStringPool,
+ DeclContextTree &ODRContexts, uint64_t ModulesEndOffset, unsigned &UnitID,
+ bool IsLittleEndian, unsigned Indent, bool Quiet) {
+ std::string PCMfile = dwarf::toString(
+ CUDie.find({dwarf::DW_AT_dwo_name, dwarf::DW_AT_GNU_dwo_name}), "");
+ if (PCMfile.empty())
+ return false;
+
+ // Clang module DWARF skeleton CUs abuse this for the path to the module.
+ uint64_t DwoId = getDwoId(CUDie, Unit);
+
+ std::string Name = dwarf::toString(CUDie.find(dwarf::DW_AT_name), "");
+ if (Name.empty()) {
+ if (!Quiet)
+ reportWarning("Anonymous module skeleton CU for " + PCMfile, OF);
+ return true;
+ }
+
+ if (!Quiet && Options.Verbose) {
+ outs().indent(Indent);
+ outs() << "Found clang module reference " << PCMfile;
+ }
+
+ auto Cached = ClangModules.find(PCMfile);
+ if (Cached != ClangModules.end()) {
+ // FIXME: Until PR27449 (https://llvm.org/bugs/show_bug.cgi?id=27449) is
+ // fixed in clang, only warn about DWO_id mismatches in verbose mode.
+ // ASTFileSignatures will change randomly when a module is rebuilt.
+ if (!Quiet && Options.Verbose && (Cached->second != DwoId))
+ reportWarning(Twine("hash mismatch: this object file was built against a "
+ "
diff erent version of the module ") +
+ PCMfile,
+ OF);
+ if (!Quiet && Options.Verbose)
+ outs() << " [cached].\n";
+ return true;
+ }
+ if (!Quiet && Options.Verbose)
+ outs() << " ...\n";
+
+ // Cyclic dependencies are disallowed by Clang, but we still
+ // shouldn't run into an infinite loop, so mark it as processed now.
+ ClangModules.insert({PCMfile, DwoId});
+
+ if (Error E =
+ loadClangModule(CUDie, PCMfile, Name, DwoId, OF, StringPool,
+ UniquingStringPool, ODRContexts, ModulesEndOffset,
+ UnitID, IsLittleEndian, Indent + 2, Quiet)) {
+ consumeError(std::move(E));
+ return false;
+ }
+ return true;
+}
+
+Error DWARFLinker::loadClangModule(
+ DWARFDie CUDie, StringRef Filename, StringRef ModuleName, uint64_t DwoId,
+ const DwarfLinkerObjFile &OF, OffsetsStringPool &StringPool,
+ UniquingStringPool &UniquingStringPool, DeclContextTree &ODRContexts,
+ uint64_t ModulesEndOffset, unsigned &UnitID, bool IsLittleEndian,
+ unsigned Indent, bool Quiet) {
+ /// Using a SmallString<0> because loadClangModule() is recursive.
+ SmallString<0> Path(Options.PrependPath);
+ if (sys::path::is_relative(Filename))
+ resolveRelativeObjectPath(Path, CUDie);
+ sys::path::append(Path, Filename);
+ // Don't use the cached binary holder because we have no thread-safety
+ // guarantee and the lifetime is limited.
+
+ if (Options.ObjFileLoader == nullptr)
+ return Error::success();
+
+ auto ErrOrObj = Options.ObjFileLoader(OF.FileName, Path);
+ if (!ErrOrObj)
+ return Error::success();
+
+ std::unique_ptr<CompileUnit> Unit;
+
+ // Setup access to the debug info.
+ auto DwarfContext = DWARFContext::create(*ErrOrObj->ObjFile);
+
+ for (const auto &CU : DwarfContext->compile_units()) {
+ updateDwarfVersion(CU->getVersion());
+ // Recursively get all modules imported by this one.
+ auto CUDie = CU->getUnitDIE(false);
+ if (!CUDie)
+ continue;
+ if (!registerModuleReference(CUDie, *CU, OF, StringPool, UniquingStringPool,
+ ODRContexts, ModulesEndOffset, UnitID,
+ IsLittleEndian, Indent, Quiet)) {
+ if (Unit) {
+ std::string Err =
+ (Filename +
+ ": Clang modules are expected to have exactly 1 compile unit.\n")
+ .str();
+ reportError(Err, OF);
+ return make_error<StringError>(Err, inconvertibleErrorCode());
+ }
+ // FIXME: Until PR27449 (https://llvm.org/bugs/show_bug.cgi?id=27449) is
+ // fixed in clang, only warn about DWO_id mismatches in verbose mode.
+ // ASTFileSignatures will change randomly when a module is rebuilt.
+ uint64_t PCMDwoId = getDwoId(CUDie, *CU);
+ if (PCMDwoId != DwoId) {
+ if (!Quiet && Options.Verbose)
+ reportWarning(
+ Twine("hash mismatch: this object file was built against a "
+ "
diff erent version of the module ") +
+ Filename,
+ OF);
+ // Update the cache entry with the DwoId of the module loaded from disk.
+ ClangModules[Filename] = PCMDwoId;
+ }
+
+ // Add this module.
+ Unit = std::make_unique<CompileUnit>(*CU, UnitID++, !Options.NoODR,
+ ModuleName);
+ Unit->setHasInterestingContent();
+ analyzeContextInfo(CUDie, 0, *Unit, &ODRContexts.getRoot(),
+ UniquingStringPool, ODRContexts, ModulesEndOffset,
+ Options.ParseableSwiftInterfaces,
+ [&](const Twine &Warning, const DWARFDie &DIE) {
+ reportWarning(Warning, OF, &DIE);
+ });
+ // Keep everything.
+ Unit->markEverythingAsKept();
+ }
+ }
+ if (!Unit->getOrigUnit().getUnitDIE().hasChildren())
+ return Error::success();
+ if (!Quiet && Options.Verbose) {
+ outs().indent(Indent);
+ outs() << "cloning .debug_info from " << Filename << "\n";
+ }
+
+ UnitListTy CompileUnits;
+ CompileUnits.push_back(std::move(Unit));
+ assert(DwarfEmitter);
+ DIECloner(*this, DwarfEmitter, *ErrOrObj, DIEAlloc, CompileUnits,
+ Options.Update)
+ .cloneAllCompileUnits(*DwarfContext, OF, StringPool, IsLittleEndian);
+ return Error::success();
+}
+
+void DWARFLinker::DIECloner::cloneAllCompileUnits(DWARFContext &DwarfContext,
+ const DwarfLinkerObjFile &OF,
+ OffsetsStringPool &StringPool,
+ bool IsLittleEndian) {
+ uint64_t OutputDebugInfoSize =
+ Linker.Options.NoOutput ? 0 : Emitter->getDebugInfoSectionSize();
+ for (auto &CurrentUnit : CompileUnits) {
+ auto InputDIE = CurrentUnit->getOrigUnit().getUnitDIE();
+ CurrentUnit->setStartOffset(OutputDebugInfoSize);
+ if (!InputDIE) {
+ OutputDebugInfoSize = CurrentUnit->computeNextUnitOffset();
+ continue;
+ }
+ if (CurrentUnit->getInfo(0).Keep) {
+ // Clone the InputDIE into your Unit DIE in our compile unit since it
+ // already has a DIE inside of it.
+ CurrentUnit->createOutputDIE();
+ cloneDIE(InputDIE, OF, *CurrentUnit, StringPool, 0 /* PC offset */,
+ 11 /* Unit Header size */, 0, IsLittleEndian,
+ CurrentUnit->getOutputUnitDIE());
+ }
+
+ OutputDebugInfoSize = CurrentUnit->computeNextUnitOffset();
+
+ if (!Linker.Options.NoOutput) {
+ assert(Emitter);
+
+ if (LLVM_LIKELY(!Linker.Options.Update) ||
+ Linker.needToTranslateStrings())
+ Linker.patchLineTableForUnit(*CurrentUnit, DwarfContext, OF);
+
+ Linker.emitAcceleratorEntriesForUnit(*CurrentUnit);
+
+ if (LLVM_UNLIKELY(Linker.Options.Update))
+ continue;
+
+ Linker.patchRangesForUnit(*CurrentUnit, DwarfContext, OF);
+ auto ProcessExpr = [&](StringRef Bytes,
+ SmallVectorImpl<uint8_t> &Buffer) {
+ DWARFUnit &OrigUnit = CurrentUnit->getOrigUnit();
+ DataExtractor Data(Bytes, IsLittleEndian,
+ OrigUnit.getAddressByteSize());
+ cloneExpression(Data,
+ DWARFExpression(Data, OrigUnit.getVersion(),
+ OrigUnit.getAddressByteSize()),
+ OF, *CurrentUnit, Buffer);
+ };
+ Emitter->emitLocationsForUnit(*CurrentUnit, DwarfContext, ProcessExpr);
+ }
+ }
+
+ if (!Linker.Options.NoOutput) {
+ assert(Emitter);
+ // Emit all the compile unit's debug information.
+ for (auto &CurrentUnit : CompileUnits) {
+ if (LLVM_LIKELY(!Linker.Options.Update))
+ Linker.generateUnitRanges(*CurrentUnit);
+
+ CurrentUnit->fixupForwardReferences();
+
+ if (!CurrentUnit->getOutputUnitDIE())
+ continue;
+
+ assert(Emitter->getDebugInfoSectionSize() ==
+ CurrentUnit->getStartOffset());
+ Emitter->emitCompileUnitHeader(*CurrentUnit);
+ Emitter->emitDIE(*CurrentUnit->getOutputUnitDIE());
+ assert(Emitter->getDebugInfoSectionSize() ==
+ CurrentUnit->computeNextUnitOffset());
+ }
+ }
+}
+
+void DWARFLinker::updateAccelKind(DWARFContext &Dwarf) {
+ if (Options.TheAccelTableKind != AccelTableKind::Default)
+ return;
+
+ auto &DwarfObj = Dwarf.getDWARFObj();
+
+ if (!AtLeastOneDwarfAccelTable &&
+ (!DwarfObj.getAppleNamesSection().Data.empty() ||
+ !DwarfObj.getAppleTypesSection().Data.empty() ||
+ !DwarfObj.getAppleNamespacesSection().Data.empty() ||
+ !DwarfObj.getAppleObjCSection().Data.empty())) {
+ AtLeastOneAppleAccelTable = true;
+ }
+
+ if (!AtLeastOneDwarfAccelTable && !DwarfObj.getNamesSection().Data.empty()) {
+ AtLeastOneDwarfAccelTable = true;
+ }
+}
+
+bool DWARFLinker::emitPaperTrailWarnings(const DwarfLinkerObjFile &OF,
+ OffsetsStringPool &StringPool) {
+
+ if (OF.Warnings.empty() || (OF.ObjFile && (OF.ObjFile->symbols().begin() !=
+ OF.ObjFile->symbols().end())))
+ return false;
+
+ DIE *CUDie = DIE::get(DIEAlloc, dwarf::DW_TAG_compile_unit);
+ CUDie->setOffset(11);
+ StringRef Producer;
+ StringRef WarningHeader;
+
+ switch (DwarfLinkerClientID) {
+ case DwarfLinkerClient::Dsymutil:
+ Producer = StringPool.internString("dsymutil");
+ WarningHeader = "dsymutil_warning";
+ break;
+
+ default:
+ Producer = StringPool.internString("dwarfopt");
+ WarningHeader = "dwarfopt_warning";
+ break;
+ }
+
+ StringRef File = StringPool.internString(OF.FileName);
+ CUDie->addValue(DIEAlloc, dwarf::DW_AT_producer, dwarf::DW_FORM_strp,
+ DIEInteger(StringPool.getStringOffset(Producer)));
+ DIEBlock *String = new (DIEAlloc) DIEBlock();
+ DIEBlocks.push_back(String);
+ for (auto &C : File)
+ String->addValue(DIEAlloc, dwarf::Attribute(0), dwarf::DW_FORM_data1,
+ DIEInteger(C));
+ String->addValue(DIEAlloc, dwarf::Attribute(0), dwarf::DW_FORM_data1,
+ DIEInteger(0));
+
+ CUDie->addValue(DIEAlloc, dwarf::DW_AT_name, dwarf::DW_FORM_string, String);
+ for (const auto &Warning : OF.Warnings) {
+ DIE &ConstDie = CUDie->addChild(DIE::get(DIEAlloc, dwarf::DW_TAG_constant));
+ ConstDie.addValue(DIEAlloc, dwarf::DW_AT_name, dwarf::DW_FORM_strp,
+ DIEInteger(StringPool.getStringOffset(WarningHeader)));
+ ConstDie.addValue(DIEAlloc, dwarf::DW_AT_artificial, dwarf::DW_FORM_flag,
+ DIEInteger(1));
+ ConstDie.addValue(DIEAlloc, dwarf::DW_AT_const_value, dwarf::DW_FORM_strp,
+ DIEInteger(StringPool.getStringOffset(Warning)));
+ }
+ unsigned Size = 4 /* FORM_strp */ + File.size() + 1 +
+ OF.Warnings.size() * (4 + 1 + 4) + 1 /* End of children */;
+ DIEAbbrev Abbrev = CUDie->generateAbbrev();
+ assignAbbrev(Abbrev);
+ CUDie->setAbbrevNumber(Abbrev.getNumber());
+ Size += getULEB128Size(Abbrev.getNumber());
+ // Abbreviation ordering needed for classic compatibility.
+ for (auto &Child : CUDie->children()) {
+ Abbrev = Child.generateAbbrev();
+ assignAbbrev(Abbrev);
+ Child.setAbbrevNumber(Abbrev.getNumber());
+ Size += getULEB128Size(Abbrev.getNumber());
+ }
+ CUDie->setSize(Size);
+ DwarfEmitter->emitPaperTrailWarningsDie(Triple, *CUDie);
+
+ return true;
+}
+
+void DWARFLinker::copyInvariantDebugSection(const object::ObjectFile &Obj) {
+ if (!needToTranslateStrings())
+ DwarfEmitter->emitSectionContents(Obj, "debug_line");
+ DwarfEmitter->emitSectionContents(Obj, "debug_loc");
+ DwarfEmitter->emitSectionContents(Obj, "debug_ranges");
+ DwarfEmitter->emitSectionContents(Obj, "debug_frame");
+ DwarfEmitter->emitSectionContents(Obj, "debug_aranges");
+}
+
+void DWARFLinker::addObjectFile(DwarfLinkerObjFile &ObjFile) {
+ ObjectContexts.emplace_back(LinkContext(ObjFile));
+
+ if (ObjectContexts.back().DwarfContext)
+ updateAccelKind(*ObjectContexts.back().DwarfContext);
+}
+
+bool DWARFLinker::link() {
+ assert(Options.NoOutput || DwarfEmitter);
+
+ // A unique ID that identifies each compile unit.
+ unsigned UnitID = 0;
+
+ // First populate the data structure we need for each iteration of the
+ // parallel loop.
+ unsigned NumObjects = ObjectContexts.size();
+
+ // This Dwarf string pool which is only used for uniquing. This one should
+ // never be used for offsets as its not thread-safe or predictable.
+ UniquingStringPool UniquingStringPool(nullptr, true);
+
+ // This Dwarf string pool which is used for emission. It must be used
+ // serially as the order of calling getStringOffset matters for
+ // reproducibility.
+ OffsetsStringPool OffsetsStringPool(StringsTranslator, true);
+
+ // ODR Contexts for the optimize.
+ DeclContextTree ODRContexts;
+
+ // If we haven't decided on an accelerator table kind yet, we base ourselves
+ // on the DWARF we have seen so far. At this point we haven't pulled in debug
+ // information from modules yet, so it is technically possible that they
+ // would affect the decision. However, as they're built with the same
+ // compiler and flags, it is safe to assume that they will follow the
+ // decision made here.
+ if (Options.TheAccelTableKind == AccelTableKind::Default) {
+ if (AtLeastOneDwarfAccelTable && !AtLeastOneAppleAccelTable)
+ Options.TheAccelTableKind = AccelTableKind::Dwarf;
+ else
+ Options.TheAccelTableKind = AccelTableKind::Apple;
+ }
+
+ for (LinkContext &OptContext : ObjectContexts) {
+ if (Options.Verbose) {
+ if (DwarfLinkerClientID == DwarfLinkerClient::Dsymutil)
+ outs() << "DEBUG MAP OBJECT: " << OptContext.ObjectFile.FileName
+ << "\n";
+ else
+ outs() << "OBJECT FILE: " << OptContext.ObjectFile.FileName << "\n";
+ }
+
+ if (emitPaperTrailWarnings(OptContext.ObjectFile, OffsetsStringPool))
+ continue;
+
+ if (!OptContext.ObjectFile.ObjFile)
+ continue;
+ // Look for relocations that correspond to address map entries.
+
+ // there was findvalidrelocations previously ... probably we need to gather
+ // info here
+ if (LLVM_LIKELY(!Options.Update) &&
+ !OptContext.ObjectFile.Addresses->hasValidRelocs()) {
+ if (Options.Verbose)
+ outs() << "No valid relocations found. Skipping.\n";
+
+ // Set "Skip" flag as a signal to other loops that we should not
+ // process this iteration.
+ OptContext.Skip = true;
+ continue;
+ }
+
+ // Setup access to the debug info.
+ if (!OptContext.DwarfContext)
+ continue;
+
+ // In a first phase, just read in the debug info and load all clang modules.
+ OptContext.CompileUnits.reserve(
+ OptContext.DwarfContext->getNumCompileUnits());
+
+ for (const auto &CU : OptContext.DwarfContext->compile_units()) {
+ updateDwarfVersion(CU->getVersion());
+ auto CUDie = CU->getUnitDIE(false);
+ if (Options.Verbose) {
+ outs() << "Input compilation unit:";
+ DIDumpOptions DumpOpts;
+ DumpOpts.ChildRecurseDepth = 0;
+ DumpOpts.Verbose = Options.Verbose;
+ CUDie.dump(outs(), 0, DumpOpts);
+ }
+ if (CUDie && !LLVM_UNLIKELY(Options.Update))
+ registerModuleReference(CUDie, *CU, OptContext.ObjectFile,
+ OffsetsStringPool, UniquingStringPool,
+ ODRContexts, 0, UnitID,
+ OptContext.DwarfContext->isLittleEndian());
+ }
+ }
+
+ // If we haven't seen any CUs, pick an arbitrary valid Dwarf version anyway.
+ if (MaxDwarfVersion == 0)
+ MaxDwarfVersion = 3;
+
+ // At this point we know how much data we have emitted. We use this value to
+ // compare canonical DIE offsets in analyzeContextInfo to see if a definition
+ // is already emitted, without being affected by canonical die offsets set
+ // later. This prevents undeterminism when analyze and clone execute
+ // concurrently, as clone set the canonical DIE offset and analyze reads it.
+ const uint64_t ModulesEndOffset =
+ Options.NoOutput ? 0 : DwarfEmitter->getDebugInfoSectionSize();
+
+ // These variables manage the list of processed object files.
+ // The mutex and condition variable are to ensure that this is thread safe.
+ std::mutex ProcessedFilesMutex;
+ std::condition_variable ProcessedFilesConditionVariable;
+ BitVector ProcessedFiles(NumObjects, false);
+
+ // Analyzing the context info is particularly expensive so it is executed in
+ // parallel with emitting the previous compile unit.
+ auto AnalyzeLambda = [&](size_t I) {
+ auto &Context = ObjectContexts[I];
+
+ if (Context.Skip || !Context.DwarfContext)
+ return;
+
+ for (const auto &CU : Context.DwarfContext->compile_units()) {
+ updateDwarfVersion(CU->getVersion());
+ // The !registerModuleReference() condition effectively skips
+ // over fully resolved skeleton units. This second pass of
+ // registerModuleReferences doesn't do any new work, but it
+ // will collect top-level errors, which are suppressed. Module
+ // warnings were already displayed in the first iteration.
+ bool Quiet = true;
+ auto CUDie = CU->getUnitDIE(false);
+ if (!CUDie || LLVM_UNLIKELY(Options.Update) ||
+ !registerModuleReference(CUDie, *CU, Context.ObjectFile,
+ OffsetsStringPool, UniquingStringPool,
+ ODRContexts, ModulesEndOffset, UnitID,
+ Quiet)) {
+ Context.CompileUnits.push_back(std::make_unique<CompileUnit>(
+ *CU, UnitID++, !Options.NoODR && !Options.Update, ""));
+ }
+ }
+
+ // Now build the DIE parent links that we will use during the next phase.
+ for (auto &CurrentUnit : Context.CompileUnits) {
+ auto CUDie = CurrentUnit->getOrigUnit().getUnitDIE();
+ if (!CUDie)
+ continue;
+ analyzeContextInfo(CurrentUnit->getOrigUnit().getUnitDIE(), 0,
+ *CurrentUnit, &ODRContexts.getRoot(),
+ UniquingStringPool, ODRContexts, ModulesEndOffset,
+ Options.ParseableSwiftInterfaces,
+ [&](const Twine &Warning, const DWARFDie &DIE) {
+ reportWarning(Warning, Context.ObjectFile, &DIE);
+ });
+ }
+ };
+
+ // And then the remaining work in serial again.
+ // Note, although this loop runs in serial, it can run in parallel with
+ // the analyzeContextInfo loop so long as we process files with indices >=
+ // than those processed by analyzeContextInfo.
+ auto CloneLambda = [&](size_t I) {
+ auto &OptContext = ObjectContexts[I];
+ if (OptContext.Skip || !OptContext.ObjectFile.ObjFile)
+ return;
+
+ // Then mark all the DIEs that need to be present in the generated output
+ // and collect some information about them.
+ // Note that this loop can not be merged with the previous one because
+ // cross-cu references require the ParentIdx to be setup for every CU in
+ // the object file before calling this.
+ if (LLVM_UNLIKELY(Options.Update)) {
+ for (auto &CurrentUnit : OptContext.CompileUnits)
+ CurrentUnit->markEverythingAsKept();
+ copyInvariantDebugSection(*OptContext.ObjectFile.ObjFile);
+ } else {
+ for (auto &CurrentUnit : OptContext.CompileUnits)
+ lookForDIEsToKeep(
+ *OptContext.ObjectFile.Addresses,
+ OptContext.ObjectFile.Addresses->getValidAddressRanges(),
+ OptContext.CompileUnits, CurrentUnit->getOrigUnit().getUnitDIE(),
+ OptContext.ObjectFile, *CurrentUnit, 0);
+ }
+
+ // The calls to applyValidRelocs inside cloneDIE will walk the reloc
+ // array again (in the same way findValidRelocsInDebugInfo() did). We
+ // need to reset the NextValidReloc index to the beginning.
+ if (OptContext.ObjectFile.Addresses->hasValidRelocs() ||
+ LLVM_UNLIKELY(Options.Update)) {
+ DIECloner(*this, DwarfEmitter, OptContext.ObjectFile, DIEAlloc,
+ OptContext.CompileUnits, Options.Update)
+ .cloneAllCompileUnits(*OptContext.DwarfContext, OptContext.ObjectFile,
+ OffsetsStringPool,
+ OptContext.DwarfContext->isLittleEndian());
+ }
+ if (!Options.NoOutput && !OptContext.CompileUnits.empty() &&
+ LLVM_LIKELY(!Options.Update))
+ patchFrameInfoForObject(
+ OptContext.ObjectFile,
+ OptContext.ObjectFile.Addresses->getValidAddressRanges(),
+ *OptContext.DwarfContext,
+ OptContext.CompileUnits[0]->getOrigUnit().getAddressByteSize());
+
+ // Clean-up before starting working on the next object.
+ cleanupAuxiliarryData(OptContext);
+ };
+
+ auto EmitLambda = [&]() {
+ // Emit everything that's global.
+ if (!Options.NoOutput) {
+ DwarfEmitter->emitAbbrevs(Abbreviations, MaxDwarfVersion);
+ DwarfEmitter->emitStrings(OffsetsStringPool);
+ switch (Options.TheAccelTableKind) {
+ case AccelTableKind::Apple:
+ DwarfEmitter->emitAppleNames(AppleNames);
+ DwarfEmitter->emitAppleNamespaces(AppleNamespaces);
+ DwarfEmitter->emitAppleTypes(AppleTypes);
+ DwarfEmitter->emitAppleObjc(AppleObjc);
+ break;
+ case AccelTableKind::Dwarf:
+ DwarfEmitter->emitDebugNames(DebugNames);
+ break;
+ case AccelTableKind::Default:
+ llvm_unreachable("Default should have already been resolved.");
+ break;
+ }
+ }
+ };
+
+ auto AnalyzeAll = [&]() {
+ for (unsigned I = 0, E = NumObjects; I != E; ++I) {
+ AnalyzeLambda(I);
+
+ std::unique_lock<std::mutex> LockGuard(ProcessedFilesMutex);
+ ProcessedFiles.set(I);
+ ProcessedFilesConditionVariable.notify_one();
+ }
+ };
+
+ auto CloneAll = [&]() {
+ for (unsigned I = 0, E = NumObjects; I != E; ++I) {
+ {
+ std::unique_lock<std::mutex> LockGuard(ProcessedFilesMutex);
+ if (!ProcessedFiles[I]) {
+ ProcessedFilesConditionVariable.wait(
+ LockGuard, [&]() { return ProcessedFiles[I]; });
+ }
+ }
+
+ CloneLambda(I);
+ }
+ EmitLambda();
+ };
+
+ // To limit memory usage in the single threaded case, analyze and clone are
+ // run sequentially so the OptContext is freed after processing each object
+ // in endDebugObject.
+ if (Options.Threads == 1) {
+ for (unsigned I = 0, E = NumObjects; I != E; ++I) {
+ AnalyzeLambda(I);
+ CloneLambda(I);
+ }
+ EmitLambda();
+ } else {
+ ThreadPool Pool(2);
+ Pool.async(AnalyzeAll);
+ Pool.async(CloneAll);
+ Pool.wait();
+ }
+
+ return true;
+}
+
} // namespace llvm
diff --git a/llvm/tools/dsymutil/DwarfLinkerForBinary.cpp b/llvm/tools/dsymutil/DwarfLinkerForBinary.cpp
index e6e7730651c8..309dbf05e7e3 100644
--- a/llvm/tools/dsymutil/DwarfLinkerForBinary.cpp
+++ b/llvm/tools/dsymutil/DwarfLinkerForBinary.cpp
@@ -63,8 +63,6 @@
#include "llvm/Object/MachO.h"
#include "llvm/Object/ObjectFile.h"
#include "llvm/Object/SymbolicFile.h"
-#include "llvm/Remarks/RemarkFormat.h"
-#include "llvm/Remarks/RemarkLinker.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/Compiler.h"
@@ -105,87 +103,93 @@
namespace llvm {
namespace dsymutil {
-/// Similar to DWARFUnitSection::getUnitForOffset(), but returning our
-/// CompileUnit object instead.
-static CompileUnit *getUnitForOffset(const UnitListTy &Units, uint64_t Offset) {
- auto CU = std::upper_bound(
- Units.begin(), Units.end(), Offset,
- [](uint64_t LHS, const std::unique_ptr<CompileUnit> &RHS) {
- return LHS < RHS->getOrigUnit().getNextUnitOffset();
- });
- return CU != Units.end() ? CU->get() : nullptr;
-}
+static Error copySwiftInterfaces(
+ const std::map<std::string, std::string> &ParseableSwiftInterfaces,
+ StringRef Architecture, const LinkOptions &Options) {
+ std::error_code EC;
+ SmallString<128> InputPath;
+ SmallString<128> Path;
+ sys::path::append(Path, *Options.ResourceDir, "Swift", Architecture);
+ if ((EC = sys::fs::create_directories(Path.str(), true,
+ sys::fs::perms::all_all)))
+ return make_error<StringError>(
+ "cannot create directory: " + toString(errorCodeToError(EC)), EC);
+ unsigned BaseLength = Path.size();
-/// Resolve the DIE attribute reference that has been extracted in \p RefValue.
-/// The resulting DIE might be in another CompileUnit which is stored into \p
-/// ReferencedCU. \returns null if resolving fails for any reason.
-static DWARFDie resolveDIEReference(const DwarfLinkerForBinary &Linker,
- const DebugMapObject &DMO,
- const UnitListTy &Units,
- const DWARFFormValue &RefValue,
- const DWARFDie &DIE, CompileUnit *&RefCU) {
- assert(RefValue.isFormClass(DWARFFormValue::FC_Reference));
- uint64_t RefOffset = *RefValue.getAsReference();
- if ((RefCU = getUnitForOffset(Units, RefOffset)))
- if (const auto RefDie = RefCU->getOrigUnit().getDIEForOffset(RefOffset)) {
- // In a file with broken references, an attribute might point to a NULL
- // DIE.
- if (!RefDie.isNULL())
- return RefDie;
+ for (auto &I : ParseableSwiftInterfaces) {
+ StringRef ModuleName = I.first;
+ StringRef InterfaceFile = I.second;
+ if (!Options.PrependPath.empty()) {
+ InputPath.clear();
+ sys::path::append(InputPath, Options.PrependPath, InterfaceFile);
+ InterfaceFile = InputPath;
}
+ sys::path::append(Path, ModuleName);
+ Path.append(".swiftinterface");
+ if (Options.Verbose)
+ outs() << "copy parseable Swift interface " << InterfaceFile << " -> "
+ << Path.str() << '\n';
+
+ // copy_file attempts an APFS clone first, so this should be cheap.
+ if ((EC = sys::fs::copy_file(InterfaceFile, Path.str())))
+ warn(Twine("cannot copy parseable Swift interface ") + InterfaceFile +
+ ": " + toString(errorCodeToError(EC)));
+ Path.resize(BaseLength);
+ }
+ return Error::success();
+}
+
+/// Report a warning to the user, optionally including information about a
+/// specific \p DIE related to the warning.
+void DwarfLinkerForBinary::reportWarning(const Twine &Warning,
+ StringRef Context,
+ const DWARFDie *DIE) const {
+
+ warn(Warning, Context);
+
+ if (!Options.Verbose || !DIE)
+ return;
+
+ DIDumpOptions DumpOpts;
+ DumpOpts.ChildRecurseDepth = 0;
+ DumpOpts.Verbose = Options.Verbose;
- Linker.reportWarning("could not find referenced DIE", DMO, &DIE);
- return DWARFDie();
+ WithColor::note() << " in DIE:\n";
+ DIE->dump(errs(), 6 /* Indent */, DumpOpts);
}
-/// \returns whether the passed \a Attr type might contain a DIE reference
-/// suitable for ODR uniquing.
-static bool isODRAttribute(uint16_t Attr) {
- switch (Attr) {
- default:
- return false;
- case dwarf::DW_AT_type:
- case dwarf::DW_AT_containing_type:
- case dwarf::DW_AT_specification:
- case dwarf::DW_AT_abstract_origin:
- case dwarf::DW_AT_import:
+bool DwarfLinkerForBinary::createStreamer(const Triple &TheTriple,
+ raw_fd_ostream &OutFile) {
+ if (Options.NoOutput)
return true;
- }
- llvm_unreachable("Improper attribute.");
+
+ Streamer = std::make_unique<DwarfStreamer>(OutFile, Options);
+ return Streamer->init(TheTriple);
}
-static bool isTypeTag(uint16_t Tag) {
- switch (Tag) {
- case dwarf::DW_TAG_array_type:
- case dwarf::DW_TAG_class_type:
- case dwarf::DW_TAG_enumeration_type:
- case dwarf::DW_TAG_pointer_type:
- case dwarf::DW_TAG_reference_type:
- case dwarf::DW_TAG_string_type:
- case dwarf::DW_TAG_structure_type:
- case dwarf::DW_TAG_subroutine_type:
- case dwarf::DW_TAG_typedef:
- case dwarf::DW_TAG_union_type:
- case dwarf::DW_TAG_ptr_to_member_type:
- case dwarf::DW_TAG_set_type:
- case dwarf::DW_TAG_subrange_type:
- case dwarf::DW_TAG_base_type:
- case dwarf::DW_TAG_const_type:
- case dwarf::DW_TAG_constant:
- case dwarf::DW_TAG_file_type:
- case dwarf::DW_TAG_namelist:
- case dwarf::DW_TAG_packed_type:
- case dwarf::DW_TAG_volatile_type:
- case dwarf::DW_TAG_restrict_type:
- case dwarf::DW_TAG_atomic_type:
- case dwarf::DW_TAG_interface_type:
- case dwarf::DW_TAG_unspecified_type:
- case dwarf::DW_TAG_shared_type:
- return true;
- default:
- break;
+ErrorOr<const object::ObjectFile &>
+DwarfLinkerForBinary::loadObject(const DebugMapObject &Obj,
+ const Triple &Triple) {
+ auto ObjectEntry =
+ BinHolder.getObjectEntry(Obj.getObjectFilename(), Obj.getTimestamp());
+ if (!ObjectEntry) {
+ auto Err = ObjectEntry.takeError();
+ reportWarning(Twine(Obj.getObjectFilename()) + ": " +
+ toString(std::move(Err)),
+ Obj.getObjectFilename());
+ return errorToErrorCode(std::move(Err));
}
- return false;
+
+ auto Object = ObjectEntry->getObject(Triple);
+ if (!Object) {
+ auto Err = Object.takeError();
+ reportWarning(Twine(Obj.getObjectFilename()) + ": " +
+ toString(std::move(Err)),
+ Obj.getObjectFilename());
+ return errorToErrorCode(std::move(Err));
+ }
+
+ return *Object;
}
static Error remarksErrorHandler(const DebugMapObject &DMO,
@@ -203,7 +207,7 @@ static Error remarksErrorHandler(const DebugMapObject &DMO,
if (EC->convertToErrorCode() != std::errc::no_such_file_or_directory)
return Error(std::move(EC));
- Linker.reportWarning(Message, DMO);
+ Linker.reportWarning(Message, DMO.getObjectFilename());
return Error(Error::success());
});
@@ -213,205 +217,227 @@ static Error remarksErrorHandler(const DebugMapObject &DMO,
return createFileError(FE->getFileName(), std::move(NewE));
}
-bool DwarfLinkerForBinary::DIECloner::getDIENames(const DWARFDie &Die,
- AttributesInfo &Info,
- OffsetsStringPool &StringPool,
- bool StripTemplate) {
- // This function will be called on DIEs having low_pcs and
- // ranges. As getting the name might be more expansive, filter out
- // blocks directly.
- if (Die.getTag() == dwarf::DW_TAG_lexical_block)
- return false;
+static Error emitRemarks(const LinkOptions &Options, StringRef BinaryPath,
+ StringRef ArchName, const remarks::RemarkLinker &RL) {
+ // Make sure we don't create the directories and the file if there is nothing
+ // to serialize.
+ if (RL.empty())
+ return Error::success();
+
+ SmallString<128> InputPath;
+ SmallString<128> Path;
+ // Create the "Remarks" directory in the "Resources" directory.
+ sys::path::append(Path, *Options.ResourceDir, "Remarks");
+ if (std::error_code EC = sys::fs::create_directories(Path.str(), true,
+ sys::fs::perms::all_all))
+ return errorCodeToError(EC);
- // FIXME: a bit wasteful as the first getName might return the
- // short name.
- if (!Info.MangledName)
- if (const char *MangledName = Die.getName(DINameKind::LinkageName))
- Info.MangledName = StringPool.getEntry(MangledName);
-
- if (!Info.Name)
- if (const char *Name = Die.getName(DINameKind::ShortName))
- Info.Name = StringPool.getEntry(Name);
-
- if (StripTemplate && Info.Name && Info.MangledName != Info.Name) {
- // FIXME: dsymutil compatibility. This is wrong for operator<
- auto Split = Info.Name.getString().split('<');
- if (!Split.second.empty())
- Info.NameWithoutTemplate = StringPool.getEntry(Split.first);
+ // Append the file name.
+ // For fat binaries, also append a dash and the architecture name.
+ sys::path::append(Path, sys::path::filename(BinaryPath));
+ if (Options.NumDebugMaps > 1) {
+ // More than one debug map means we have a fat binary.
+ Path += '-';
+ Path += ArchName;
}
- return Info.Name || Info.MangledName;
+ std::error_code EC;
+ raw_fd_ostream OS(Options.NoOutput ? "-" : Path.str(), EC, sys::fs::OF_None);
+ if (EC)
+ return errorCodeToError(EC);
+
+ if (Error E = RL.serialize(OS, Options.RemarksFormat))
+ return E;
+
+ return Error::success();
}
-/// Report a warning to the user, optionally including information about a
-/// specific \p DIE related to the warning.
-void DwarfLinkerForBinary::reportWarning(const Twine &Warning,
- const DebugMapObject &DMO,
- const DWARFDie *DIE) const {
- StringRef Context = DMO.getObjectFilename();
- warn(Warning, Context);
+ErrorOr<DwarfLinkerObjFile &>
+DwarfLinkerForBinary::loadObject(const DebugMapObject &Obj,
+ const DebugMap &DebugMap,
+ remarks::RemarkLinker &RL) {
+ auto ErrorOrObj = loadObject(Obj, DebugMap.getTriple());
- if (!Options.Verbose || !DIE)
- return;
+ if (ErrorOrObj) {
+ ObjectsForLinking.push_back(
+ std::unique_ptr<DwarfLinkerObjFile>(new DwarfLinkerObjFile(
+ Obj.getObjectFilename(), &*ErrorOrObj, Obj.getWarnings())));
- DIDumpOptions DumpOpts;
- DumpOpts.ChildRecurseDepth = 0;
- DumpOpts.Verbose = Options.Verbose;
+ ObjectsForLinking.back()->Addresses.reset(
+ new AddressManager(*this, *ErrorOrObj, Obj));
- WithColor::note() << " in DIE:\n";
- DIE->dump(errs(), 6 /* Indent */, DumpOpts);
-}
+ Error E = RL.link(*ObjectsForLinking.back()->ObjFile);
+ if (Error NewE = handleErrors(
+ std::move(E), [&](std::unique_ptr<FileError> EC) -> Error {
+ return remarksErrorHandler(Obj, *this, std::move(EC));
+ }))
+ return errorToErrorCode(std::move(NewE));
-bool DwarfLinkerForBinary::createStreamer(const Triple &TheTriple,
- raw_fd_ostream &OutFile) {
- if (Options.NoOutput)
- return true;
+ return *ObjectsForLinking.back();
+ }
- Streamer = std::make_unique<DwarfStreamer>(OutFile, Options);
- return Streamer->init(TheTriple);
+ return ErrorOrObj.getError();
}
-/// Resolve the relative path to a build artifact referenced by DWARF by
-/// applying DW_AT_comp_dir.
-static void resolveRelativeObjectPath(SmallVectorImpl<char> &Buf, DWARFDie CU) {
- sys::path::append(Buf, dwarf::toString(CU.find(dwarf::DW_AT_comp_dir), ""));
-}
+bool DwarfLinkerForBinary::link(const DebugMap &Map) {
+ if (!createStreamer(Map.getTriple(), OutFile))
+ return false;
-/// Collect references to parseable Swift interfaces in imported
-/// DW_TAG_module blocks.
-static void analyzeImportedModule(
- const DWARFDie &DIE, CompileUnit &CU,
- std::map<std::string, std::string> &ParseableSwiftInterfaces,
- std::function<void(const Twine &, const DWARFDie &)> ReportWarning) {
- if (CU.getLanguage() != dwarf::DW_LANG_Swift)
- return;
+ ObjectsForLinking.clear();
- StringRef Path = dwarf::toStringRef(DIE.find(dwarf::DW_AT_LLVM_include_path));
- if (!Path.endswith(".swiftinterface"))
- return;
- if (Optional<DWARFFormValue> Val = DIE.find(dwarf::DW_AT_name))
- if (Optional<const char *> Name = Val->getAsCString()) {
- auto &Entry = ParseableSwiftInterfaces[*Name];
- // The prepend path is applied later when copying.
- DWARFDie CUDie = CU.getOrigUnit().getUnitDIE();
- SmallString<128> ResolvedPath;
- if (sys::path::is_relative(Path))
- resolveRelativeObjectPath(ResolvedPath, CUDie);
- sys::path::append(ResolvedPath, Path);
- if (!Entry.empty() && Entry != ResolvedPath)
- ReportWarning(
- Twine("Conflicting parseable interfaces for Swift Module ") +
- *Name + ": " + Entry + " and " + Path,
- DIE);
- Entry = ResolvedPath.str();
- }
-}
+ DebugMap DebugMap(Map.getTriple(), Map.getBinaryPath());
-/// Recursive helper to build the global DeclContext information and
-/// gather the child->parent relationships in the original compile unit.
-///
-/// \return true when this DIE and all of its children are only
-/// forward declarations to types defined in external clang modules
-/// (i.e., forward declarations that are children of a DW_TAG_module).
-static bool analyzeContextInfo(
- const DWARFDie &DIE, unsigned ParentIdx, CompileUnit &CU,
- DeclContext *CurrentDeclContext, UniquingStringPool &StringPool,
- DeclContextTree &Contexts, uint64_t ModulesEndOffset,
- std::map<std::string, std::string> &ParseableSwiftInterfaces,
- std::function<void(const Twine &, const DWARFDie &)> ReportWarning,
- bool InImportedModule = false) {
- unsigned MyIdx = CU.getOrigUnit().getDIEIndex(DIE);
- CompileUnit::DIEInfo &Info = CU.getInfo(MyIdx);
-
- // Clang imposes an ODR on modules(!) regardless of the language:
- // "The module-id should consist of only a single identifier,
- // which provides the name of the module being defined. Each
- // module shall have a single definition."
- //
- // This does not extend to the types inside the modules:
- // "[I]n C, this implies that if two structs are defined in
- //
diff erent submodules with the same name, those two types are
- // distinct types (but may be compatible types if their
- // definitions match)."
- //
- // We treat non-C++ modules like namespaces for this reason.
- if (DIE.getTag() == dwarf::DW_TAG_module && ParentIdx == 0 &&
- dwarf::toString(DIE.find(dwarf::DW_AT_name), "") !=
- CU.getClangModuleName()) {
- InImportedModule = true;
- analyzeImportedModule(DIE, CU, ParseableSwiftInterfaces, ReportWarning);
- }
+ DWARFLinker GeneralLinker(Map.getTriple(), Streamer.get(),
+ DwarfLinkerClient::Dsymutil);
- Info.ParentIdx = ParentIdx;
- bool InClangModule = CU.isClangModule() || InImportedModule;
- if (CU.hasODR() || InClangModule) {
- if (CurrentDeclContext) {
- auto PtrInvalidPair = Contexts.getChildDeclContext(
- *CurrentDeclContext, DIE, CU, StringPool, InClangModule);
- CurrentDeclContext = PtrInvalidPair.getPointer();
- Info.Ctxt =
- PtrInvalidPair.getInt() ? nullptr : PtrInvalidPair.getPointer();
- if (Info.Ctxt)
- Info.Ctxt->setDefinedInClangModule(InClangModule);
- } else
- Info.Ctxt = CurrentDeclContext = nullptr;
- }
+ remarks::RemarkLinker RL;
+ if (!Options.RemarksPrependPath.empty())
+ RL.setExternalFilePrependPath(Options.RemarksPrependPath);
- Info.Prune = InImportedModule;
- if (DIE.hasChildren())
- for (auto Child : DIE.children())
- Info.Prune &= analyzeContextInfo(Child, MyIdx, CU, CurrentDeclContext,
- StringPool, Contexts, ModulesEndOffset,
- ParseableSwiftInterfaces, ReportWarning,
- InImportedModule);
-
- // Prune this DIE if it is either a forward declaration inside a
- // DW_TAG_module or a DW_TAG_module that contains nothing but
- // forward declarations.
- Info.Prune &= (DIE.getTag() == dwarf::DW_TAG_module) ||
- (isTypeTag(DIE.getTag()) &&
- dwarf::toUnsigned(DIE.find(dwarf::DW_AT_declaration), 0));
-
- // Only prune forward declarations inside a DW_TAG_module for which a
- // definition exists elsewhere.
- if (ModulesEndOffset == 0)
- Info.Prune &= Info.Ctxt && Info.Ctxt->getCanonicalDIEOffset();
- else
- Info.Prune &= Info.Ctxt && Info.Ctxt->getCanonicalDIEOffset() > 0 &&
- Info.Ctxt->getCanonicalDIEOffset() <= ModulesEndOffset;
+ std::function<StringRef(StringRef)> TranslationLambda = [&](StringRef Input) {
+ assert(Options.Translator);
+ return Options.Translator(Input);
+ };
- return Info.Prune;
-} // namespace dsymutil
+ GeneralLinker.setVerbosity(Options.Verbose);
+ GeneralLinker.setNoOutput(Options.NoOutput);
+ GeneralLinker.setNoODR(Options.NoODR);
+ GeneralLinker.setUpdate(Options.Update);
+ GeneralLinker.setNumThreads(Options.Threads);
+ GeneralLinker.setAccelTableKind(Options.TheAccelTableKind);
+ GeneralLinker.setPrependPath(Options.PrependPath);
+ if (Options.Translator)
+ GeneralLinker.setStringsTranslator(TranslationLambda);
+ GeneralLinker.setWarningHandler(
+ [&](const Twine &Warning, StringRef Context, const DWARFDie *DIE) {
+ reportWarning(Warning, Context, DIE);
+ });
+ GeneralLinker.setErrorHandler(
+ [&](const Twine &Error, StringRef Context, const DWARFDie *DIE) {
+ error(Error, Context);
+ });
+ GeneralLinker.setObjFileLoader(
+ [&DebugMap, &RL, this](StringRef ContainerName,
+ StringRef Path) -> ErrorOr<DwarfLinkerObjFile &> {
+ auto &Obj = DebugMap.addDebugMapObject(
+ Path, sys::TimePoint<std::chrono::seconds>(), MachO::N_OSO);
+
+ if (auto ErrorOrObj = loadObject(Obj, DebugMap, RL)) {
+ return *ErrorOrObj;
+ } else {
+ // Try and emit more helpful warnings by applying some heuristics.
+ StringRef ObjFile = ContainerName;
+ bool IsClangModule = sys::path::extension(Path).equals(".pcm");
+ bool IsArchive = ObjFile.endswith(")");
+
+ if (IsClangModule) {
+ StringRef ModuleCacheDir = sys::path::parent_path(Path);
+ if (sys::fs::exists(ModuleCacheDir)) {
+ // If the module's parent directory exists, we assume that the
+ // module cache has expired and was pruned by clang. A more
+ // adventurous dsymutil would invoke clang to rebuild the module
+ // now.
+ if (!ModuleCacheHintDisplayed) {
+ WithColor::note()
+ << "The clang module cache may have expired since "
+ "this object file was built. Rebuilding the "
+ "object file will rebuild the module cache.\n";
+ ModuleCacheHintDisplayed = true;
+ }
+ } else if (IsArchive) {
+ // If the module cache directory doesn't exist at all and the
+ // object file is inside a static library, we assume that the
+ // static library was built on a
diff erent machine. We don't want
+ // to discourage module debugging for convenience libraries within
+ // a project though.
+ if (!ArchiveHintDisplayed) {
+ WithColor::note()
+ << "Linking a static library that was built with "
+ "-gmodules, but the module cache was not found. "
+ "Redistributable static libraries should never be "
+ "built with module debugging enabled. The debug "
+ "experience will be degraded due to incomplete "
+ "debug information.\n";
+ ArchiveHintDisplayed = true;
+ }
+ }
+ }
-static bool dieNeedsChildrenToBeMeaningful(uint32_t Tag) {
- switch (Tag) {
- default:
- return false;
- case dwarf::DW_TAG_class_type:
- case dwarf::DW_TAG_common_block:
- case dwarf::DW_TAG_lexical_block:
- case dwarf::DW_TAG_structure_type:
- case dwarf::DW_TAG_subprogram:
- case dwarf::DW_TAG_subroutine_type:
- case dwarf::DW_TAG_union_type:
- return true;
+ return ErrorOrObj.getError();
+ }
+
+ llvm_unreachable("Unhandled DebugMap object");
+ });
+ GeneralLinker.setSwiftInterfacesMap(&ParseableSwiftInterfaces);
+
+ for (const auto &Obj : Map.objects()) {
+ // N_AST objects (swiftmodule files) should get dumped directly into the
+ // appropriate DWARF section.
+ if (Obj->getType() == MachO::N_AST) {
+ if (Options.Verbose)
+ outs() << "DEBUG MAP OBJECT: " << Obj->getObjectFilename() << "\n";
+
+ StringRef File = Obj->getObjectFilename();
+ auto ErrorOrMem = MemoryBuffer::getFile(File);
+ if (!ErrorOrMem) {
+ warn("Could not open '" + File + "'\n");
+ continue;
+ }
+ sys::fs::file_status Stat;
+ if (auto Err = sys::fs::status(File, Stat)) {
+ warn(Err.message());
+ continue;
+ }
+ if (!Options.NoTimestamp) {
+ // The modification can have sub-second precision so we need to cast
+ // away the extra precision that's not present in the debug map.
+ auto ModificationTime =
+ std::chrono::time_point_cast<std::chrono::seconds>(
+ Stat.getLastModificationTime());
+ if (ModificationTime != Obj->getTimestamp()) {
+ // Not using the helper here as we can easily stream TimePoint<>.
+ WithColor::warning() << "Timestamp mismatch for " << File << ": "
+ << Stat.getLastModificationTime() << " and "
+ << sys::TimePoint<>(Obj->getTimestamp()) << "\n";
+ continue;
+ }
+ }
+
+ // Copy the module into the .swift_ast section.
+ if (!Options.NoOutput)
+ Streamer->emitSwiftAST((*ErrorOrMem)->getBuffer());
+
+ continue;
+ }
+
+ if (auto ErrorOrObj = loadObject(*Obj, Map, RL))
+ GeneralLinker.addObjectFile(*ErrorOrObj);
+ else {
+ ObjectsForLinking.push_back(
+ std::unique_ptr<DwarfLinkerObjFile>(new DwarfLinkerObjFile(
+ Obj->getObjectFilename(), nullptr, Obj->getWarnings())));
+ GeneralLinker.addObjectFile(*ObjectsForLinking.back());
+ }
}
- llvm_unreachable("Invalid Tag");
-}
-void DwarfLinkerForBinary::startDebugObject(LinkContext &Context) {}
+ // link debug info for loaded object files.
+ GeneralLinker.link();
+
+ StringRef ArchName = Map.getTriple().getArchName();
+ if (Error E = emitRemarks(Options, Map.getBinaryPath(), ArchName, RL))
+ return error(toString(std::move(E)));
-void DwarfLinkerForBinary::endDebugObject(LinkContext &Context) {
- Context.Clear();
+ if (Options.NoOutput)
+ return true;
- for (auto I = DIEBlocks.begin(), E = DIEBlocks.end(); I != E; ++I)
- (*I)->~DIEBlock();
- for (auto I = DIELocs.begin(), E = DIELocs.end(); I != E; ++I)
- (*I)->~DIELoc();
+ if (Options.ResourceDir && !ParseableSwiftInterfaces.empty()) {
+ StringRef ArchName = Triple::getArchTypeName(Map.getTriple().getArch());
+ if (auto E =
+ copySwiftInterfaces(ParseableSwiftInterfaces, ArchName, Options))
+ return error(toString(std::move(E)));
+ }
- DIEBlocks.clear();
- DIELocs.clear();
- DIEAlloc.Reset();
+ return Streamer->finish(Map, Options.Translator);
}
static bool isMachOPairedReloc(uint64_t RelocType, uint64_t Arch) {
@@ -437,13 +463,13 @@ static bool isMachOPairedReloc(uint64_t RelocType, uint64_t Arch) {
/// Iterate over the relocations of the given \p Section and
/// store the ones that correspond to debug map entries into the
/// ValidRelocs array.
-void DwarfLinkerForBinary::RelocationManager::findValidRelocsMachO(
+void DwarfLinkerForBinary::AddressManager::findValidRelocsMachO(
const object::SectionRef &Section, const object::MachOObjectFile &Obj,
const DebugMapObject &DMO) {
Expected<StringRef> ContentsOrErr = Section.getContents();
if (!ContentsOrErr) {
consumeError(ContentsOrErr.takeError());
- Linker.reportWarning("error reading section", DMO);
+ Linker.reportWarning("error reading section", DMO.getObjectFilename());
return;
}
DataExtractor Data(*ContentsOrErr, Obj.isLittleEndian(), 0);
@@ -462,7 +488,7 @@ void DwarfLinkerForBinary::RelocationManager::findValidRelocsMachO(
Obj.getArch())) {
SkipNext = true;
Linker.reportWarning("unsupported relocation in debug_info section.",
- DMO);
+ DMO.getObjectFilename());
continue;
}
@@ -470,7 +496,7 @@ void DwarfLinkerForBinary::RelocationManager::findValidRelocsMachO(
uint64_t Offset64 = Reloc.getOffset();
if ((RelocSize != 4 && RelocSize != 8)) {
Linker.reportWarning("unsupported relocation in debug_info section.",
- DMO);
+ DMO.getObjectFilename());
continue;
}
uint64_t OffsetCopy = Offset64;
@@ -495,7 +521,8 @@ void DwarfLinkerForBinary::RelocationManager::findValidRelocsMachO(
Expected<StringRef> SymbolName = Sym->getName();
if (!SymbolName) {
consumeError(SymbolName.takeError());
- Linker.reportWarning("error getting relocation symbol name.", DMO);
+ Linker.reportWarning("error getting relocation symbol name.",
+ DMO.getObjectFilename());
continue;
}
if (const auto *Mapping = DMO.lookupSymbol(*SymbolName))
@@ -511,23 +538,23 @@ void DwarfLinkerForBinary::RelocationManager::findValidRelocsMachO(
/// Dispatch the valid relocation finding logic to the
/// appropriate handler depending on the object file format.
-bool DwarfLinkerForBinary::RelocationManager::findValidRelocs(
+bool DwarfLinkerForBinary::AddressManager::findValidRelocs(
const object::SectionRef &Section, const object::ObjectFile &Obj,
const DebugMapObject &DMO) {
// Dispatch to the right handler depending on the file type.
if (auto *MachOObj = dyn_cast<object::MachOObjectFile>(&Obj))
findValidRelocsMachO(Section, *MachOObj, DMO);
else
- Linker.reportWarning(
- Twine("unsupported object file type: ") + Obj.getFileName(), DMO);
-
+ Linker.reportWarning(Twine("unsupported object file type: ") +
+ Obj.getFileName(),
+ DMO.getObjectFilename());
if (ValidRelocs.empty())
return false;
// Sort the relocations by offset. We will walk the DIEs linearly in
// the file, this allows us to just keep an index in the relocation
// array that we advance during our walk, rather than resorting to
- // some associative container. See DwarfLinker::NextValidReloc.
+ // some associative container. See DwarfLinkerForBinary::NextValidReloc.
llvm::sort(ValidRelocs);
return true;
}
@@ -537,7 +564,7 @@ bool DwarfLinkerForBinary::RelocationManager::findValidRelocs(
/// link by indicating which DIEs refer to symbols present in the
/// linked binary.
/// \returns whether there are any valid relocations in the debug info.
-bool DwarfLinkerForBinary::RelocationManager::findValidRelocsInDebugInfo(
+bool DwarfLinkerForBinary::AddressManager::findValidRelocsInDebugInfo(
const object::ObjectFile &Obj, const DebugMapObject &DMO) {
// Find the debug_info section.
for (const object::SectionRef &Section : Obj.sections()) {
@@ -561,7 +588,7 @@ bool DwarfLinkerForBinary::RelocationManager::findValidRelocsInDebugInfo(
/// This function must be called with offsets in strictly ascending
/// order because it never looks back at relocations it already 'went past'.
/// \returns true and sets Info.InDebugMap if it is the case.
-bool DwarfLinkerForBinary::RelocationManager::hasValidRelocationAt(
+bool DwarfLinkerForBinary::AddressManager::hasValidRelocationAt(
uint64_t StartOffset, uint64_t EndOffset, CompileUnit::DIEInfo &Info) {
assert(NextValidReloc == 0 ||
StartOffset > ValidRelocs[NextValidReloc - 1].Offset);
@@ -599,2454 +626,51 @@ bool DwarfLinkerForBinary::RelocationManager::hasValidRelocationAt(
return true;
}
-/// Get the starting and ending (exclusive) offset for the
-/// attribute with index \p Idx descibed by \p Abbrev. \p Offset is
-/// supposed to point to the position of the first attribute described
-/// by \p Abbrev.
-/// \return [StartOffset, EndOffset) as a pair.
-static std::pair<uint64_t, uint64_t>
-getAttributeOffsets(const DWARFAbbreviationDeclaration *Abbrev, unsigned Idx,
- uint64_t Offset, const DWARFUnit &Unit) {
- DataExtractor Data = Unit.getDebugInfoExtractor();
-
- for (unsigned i = 0; i < Idx; ++i)
- DWARFFormValue::skipValue(Abbrev->getFormByIndex(i), Data, &Offset,
- Unit.getFormParams());
-
- uint64_t End = Offset;
- DWARFFormValue::skipValue(Abbrev->getFormByIndex(Idx), Data, &End,
- Unit.getFormParams());
-
- return std::make_pair(Offset, End);
-}
-
-/// Check if a variable describing DIE should be kept.
-/// \returns updated TraversalFlags.
-unsigned DwarfLinkerForBinary::shouldKeepVariableDIE(
- RelocationManager &RelocMgr, const DWARFDie &DIE, CompileUnit &Unit,
- CompileUnit::DIEInfo &MyInfo, unsigned Flags) {
- const auto *Abbrev = DIE.getAbbreviationDeclarationPtr();
-
- // Global variables with constant value can always be kept.
- if (!(Flags & TF_InFunctionScope) &&
- Abbrev->findAttributeIndex(dwarf::DW_AT_const_value)) {
- MyInfo.InDebugMap = true;
- return Flags | TF_Keep;
- }
-
- Optional<uint32_t> LocationIdx =
- Abbrev->findAttributeIndex(dwarf::DW_AT_location);
- if (!LocationIdx)
- return Flags;
-
- uint64_t Offset = DIE.getOffset() + getULEB128Size(Abbrev->getCode());
- const DWARFUnit &OrigUnit = Unit.getOrigUnit();
- uint64_t LocationOffset, LocationEndOffset;
- std::tie(LocationOffset, LocationEndOffset) =
- getAttributeOffsets(Abbrev, *LocationIdx, Offset, OrigUnit);
-
- // See if there is a relocation to a valid debug map entry inside
- // this variable's location. The order is important here. We want to
- // always check if the variable has a valid relocation, so that the
- // DIEInfo is filled. However, we don't want a static variable in a
- // function to force us to keep the enclosing function.
- if (!RelocMgr.hasValidRelocationAt(LocationOffset, LocationEndOffset,
- MyInfo) ||
- (Flags & TF_InFunctionScope))
- return Flags;
-
- if (Options.Verbose) {
- outs() << "Keeping variable DIE:";
- DIDumpOptions DumpOpts;
- DumpOpts.ChildRecurseDepth = 0;
- DumpOpts.Verbose = Options.Verbose;
- DIE.dump(outs(), 8 /* Indent */, DumpOpts);
- }
-
- return Flags | TF_Keep;
-}
-
-/// Check if a function describing DIE should be kept.
-/// \returns updated TraversalFlags.
-unsigned DwarfLinkerForBinary::shouldKeepSubprogramDIE(
- RelocationManager &RelocMgr, RangesTy &Ranges, const DWARFDie &DIE,
- const DebugMapObject &DMO, CompileUnit &Unit, CompileUnit::DIEInfo &MyInfo,
- unsigned Flags) {
- const auto *Abbrev = DIE.getAbbreviationDeclarationPtr();
-
- Flags |= TF_InFunctionScope;
-
- Optional<uint32_t> LowPcIdx = Abbrev->findAttributeIndex(dwarf::DW_AT_low_pc);
- if (!LowPcIdx)
- return Flags;
-
- uint64_t Offset = DIE.getOffset() + getULEB128Size(Abbrev->getCode());
- DWARFUnit &OrigUnit = Unit.getOrigUnit();
- uint64_t LowPcOffset, LowPcEndOffset;
- std::tie(LowPcOffset, LowPcEndOffset) =
- getAttributeOffsets(Abbrev, *LowPcIdx, Offset, OrigUnit);
-
- auto LowPc = dwarf::toAddress(DIE.find(dwarf::DW_AT_low_pc));
- assert(LowPc.hasValue() && "low_pc attribute is not an address.");
- if (!LowPc ||
- !RelocMgr.hasValidRelocationAt(LowPcOffset, LowPcEndOffset, MyInfo))
- return Flags;
-
- if (Options.Verbose) {
- outs() << "Keeping subprogram DIE:";
- DIDumpOptions DumpOpts;
- DumpOpts.ChildRecurseDepth = 0;
- DumpOpts.Verbose = Options.Verbose;
- DIE.dump(outs(), 8 /* Indent */, DumpOpts);
- }
-
- if (DIE.getTag() == dwarf::DW_TAG_label) {
- if (Unit.hasLabelAt(*LowPc))
- return Flags;
- // FIXME: dsymutil-classic compat. dsymutil-classic doesn't consider labels
- // that don't fall into the CU's aranges. This is wrong IMO. Debug info
- // generation bugs aside, this is really wrong in the case of labels, where
- // a label marking the end of a function will have a PC == CU's high_pc.
- if (dwarf::toAddress(OrigUnit.getUnitDIE().find(dwarf::DW_AT_high_pc))
- .getValueOr(UINT64_MAX) <= LowPc)
- return Flags;
- Unit.addLabelLowPc(*LowPc, MyInfo.AddrAdjust);
- return Flags | TF_Keep;
- }
-
- Flags |= TF_Keep;
-
- Optional<uint64_t> HighPc = DIE.getHighPC(*LowPc);
- if (!HighPc) {
- reportWarning("Function without high_pc. Range will be discarded.\n", DMO,
- &DIE);
- return Flags;
- }
+/// Apply the valid relocations found by findValidRelocs() to
+/// the buffer \p Data, taking into account that Data is at \p BaseOffset
+/// in the debug_info section.
+///
+/// Like for findValidRelocs(), this function must be called with
+/// monotonic \p BaseOffset values.
+///
+/// \returns whether any reloc has been applied.
+bool DwarfLinkerForBinary::AddressManager::applyValidRelocs(
+ MutableArrayRef<char> Data, uint64_t BaseOffset, bool IsLittleEndian) {
+ assert(areRelocationsResolved());
+ assert((NextValidReloc == 0 ||
+ BaseOffset > ValidRelocs[NextValidReloc - 1].Offset) &&
+ "BaseOffset should only be increasing.");
+ if (NextValidReloc >= ValidRelocs.size())
+ return false;
- // Replace the debug map range with a more accurate one.
- Ranges[*LowPc] = ObjFileAddressRange(*HighPc, MyInfo.AddrAdjust);
- Unit.addFunctionRange(*LowPc, *HighPc, MyInfo.AddrAdjust);
- return Flags;
-}
+ // Skip relocs that haven't been applied.
+ while (NextValidReloc < ValidRelocs.size() &&
+ ValidRelocs[NextValidReloc].Offset < BaseOffset)
+ ++NextValidReloc;
-/// Check if a DIE should be kept.
-/// \returns updated TraversalFlags.
-unsigned DwarfLinkerForBinary::shouldKeepDIE(
- RelocationManager &RelocMgr, RangesTy &Ranges, const DWARFDie &DIE,
- const DebugMapObject &DMO, CompileUnit &Unit, CompileUnit::DIEInfo &MyInfo,
- unsigned Flags) {
- switch (DIE.getTag()) {
- case dwarf::DW_TAG_constant:
- case dwarf::DW_TAG_variable:
- return shouldKeepVariableDIE(RelocMgr, DIE, Unit, MyInfo, Flags);
- case dwarf::DW_TAG_subprogram:
- case dwarf::DW_TAG_label:
- return shouldKeepSubprogramDIE(RelocMgr, Ranges, DIE, DMO, Unit, MyInfo,
- Flags);
- case dwarf::DW_TAG_base_type:
- // DWARF Expressions may reference basic types, but scanning them
- // is expensive. Basic types are tiny, so just keep all of them.
- case dwarf::DW_TAG_imported_module:
- case dwarf::DW_TAG_imported_declaration:
- case dwarf::DW_TAG_imported_unit:
- // We always want to keep these.
- return Flags | TF_Keep;
- default:
- break;
+ bool Applied = false;
+ uint64_t EndOffset = BaseOffset + Data.size();
+ while (NextValidReloc < ValidRelocs.size() &&
+ ValidRelocs[NextValidReloc].Offset >= BaseOffset &&
+ ValidRelocs[NextValidReloc].Offset < EndOffset) {
+ const auto &ValidReloc = ValidRelocs[NextValidReloc++];
+ assert(ValidReloc.Offset - BaseOffset < Data.size());
+ assert(ValidReloc.Offset - BaseOffset + ValidReloc.Size <= Data.size());
+ char Buf[8];
+ uint64_t Value = ValidReloc.Mapping->getValue().BinaryAddress;
+ Value += ValidReloc.Addend;
+ for (unsigned I = 0; I != ValidReloc.Size; ++I) {
+ unsigned Index = IsLittleEndian ? I : (ValidReloc.Size - I - 1);
+ Buf[I] = uint8_t(Value >> (Index * 8));
+ }
+ assert(ValidReloc.Size <= sizeof(Buf));
+ memcpy(&Data[ValidReloc.Offset - BaseOffset], Buf, ValidReloc.Size);
+ Applied = true;
}
- return Flags;
+ return Applied;
}
-namespace {
-/// The distinct types of work performed by the work loop.
-enum class WorklistItemType {
- /// Given a DIE, look for DIEs to be kept.
- LookForDIEsToKeep,
- /// Given a DIE, look for children of this DIE to be kept.
- LookForChildDIEsToKeep,
- /// Given a DIE, look for DIEs referencing this DIE to be kept.
- LookForRefDIEsToKeep,
- /// Given a DIE, look for parent DIEs to be kept.
- LookForParentDIEsToKeep,
- /// Given a DIE, update its incompleteness based on whether its children are
- /// incomplete.
- UpdateChildIncompleteness,
- /// Given a DIE, update its incompleteness based on whether the DIEs it
- /// references are incomplete.
- UpdateRefIncompleteness,
-};
-
-/// This class represents an item in the work list. The type defines what kind
-/// of work needs to be performed when processing the current item. The flags
-/// and info fields are optional based on the type.
-struct WorklistItem {
- WorklistItemType Type;
- DWARFDie Die;
- CompileUnit &CU;
- unsigned Flags;
- unsigned AncestorIdx = 0;
- CompileUnit::DIEInfo *OtherInfo = nullptr;
-
- WorklistItem(DWARFDie Die, CompileUnit &CU, unsigned Flags,
- WorklistItemType T = WorklistItemType::LookForDIEsToKeep)
- : Type(T), Die(Die), CU(CU), Flags(Flags){};
-
- WorklistItem(DWARFDie Die, CompileUnit &CU, WorklistItemType T,
- CompileUnit::DIEInfo *OtherInfo = nullptr)
- : Type(T), Die(Die), CU(CU), OtherInfo(OtherInfo){};
-
- WorklistItem(unsigned AncestorIdx, CompileUnit &CU, unsigned Flags)
- : Type(WorklistItemType::LookForParentDIEsToKeep), CU(CU), Flags(Flags),
- AncestorIdx(AncestorIdx){};
-};
-} // namespace
-
-/// Helper that updates the completeness of the current DIE based on the
-/// completeness of one of its children. It depends on the incompleteness of
-/// the children already being computed.
-static void updateChildIncompleteness(const DWARFDie &Die, CompileUnit &CU,
- CompileUnit::DIEInfo &ChildInfo) {
- switch (Die.getTag()) {
- case dwarf::DW_TAG_structure_type:
- case dwarf::DW_TAG_class_type:
- break;
- default:
- return;
- }
-
- unsigned Idx = CU.getOrigUnit().getDIEIndex(Die);
- CompileUnit::DIEInfo &MyInfo = CU.getInfo(Idx);
-
- if (ChildInfo.Incomplete || ChildInfo.Prune)
- MyInfo.Incomplete = true;
-}
-
-/// Helper that updates the completeness of the current DIE based on the
-/// completeness of the DIEs it references. It depends on the incompleteness of
-/// the referenced DIE already being computed.
-static void updateRefIncompleteness(const DWARFDie &Die, CompileUnit &CU,
- CompileUnit::DIEInfo &RefInfo) {
- switch (Die.getTag()) {
- case dwarf::DW_TAG_typedef:
- case dwarf::DW_TAG_member:
- case dwarf::DW_TAG_reference_type:
- case dwarf::DW_TAG_ptr_to_member_type:
- case dwarf::DW_TAG_pointer_type:
- break;
- default:
- return;
- }
-
- unsigned Idx = CU.getOrigUnit().getDIEIndex(Die);
- CompileUnit::DIEInfo &MyInfo = CU.getInfo(Idx);
-
- if (MyInfo.Incomplete)
- return;
-
- if (RefInfo.Incomplete)
- MyInfo.Incomplete = true;
-}
-
-/// Look at the children of the given DIE and decide whether they should be
-/// kept.
-static void lookForChildDIEsToKeep(const DWARFDie &Die, CompileUnit &CU,
- unsigned Flags,
- SmallVectorImpl<WorklistItem> &Worklist) {
- // The TF_ParentWalk flag tells us that we are currently walking up the
- // parent chain of a required DIE, and we don't want to mark all the children
- // of the parents as kept (consider for example a DW_TAG_namespace node in
- // the parent chain). There are however a set of DIE types for which we want
- // to ignore that directive and still walk their children.
- if (dieNeedsChildrenToBeMeaningful(Die.getTag()))
- Flags &= ~DwarfLinkerForBinary::TF_ParentWalk;
-
- // We're finished if this DIE has no children or we're walking the parent
- // chain.
- if (!Die.hasChildren() || (Flags & DwarfLinkerForBinary::TF_ParentWalk))
- return;
-
- // Add children in reverse order to the worklist to effectively process them
- // in order.
- for (auto Child : reverse(Die.children())) {
- // Add a worklist item before every child to calculate incompleteness right
- // after the current child is processed.
- unsigned Idx = CU.getOrigUnit().getDIEIndex(Child);
- CompileUnit::DIEInfo &ChildInfo = CU.getInfo(Idx);
- Worklist.emplace_back(Die, CU, WorklistItemType::UpdateChildIncompleteness,
- &ChildInfo);
- Worklist.emplace_back(Child, CU, Flags);
- }
-}
-
-/// Look at DIEs referenced by the given DIE and decide whether they should be
-/// kept. All DIEs referenced though attributes should be kept.
-static void lookForRefDIEsToKeep(const DWARFDie &Die, CompileUnit &CU,
- unsigned Flags, DwarfLinkerForBinary &Linker,
- const UnitListTy &Units,
- const DebugMapObject &DMO,
- SmallVectorImpl<WorklistItem> &Worklist) {
- bool UseOdr = (Flags & DwarfLinkerForBinary::TF_DependencyWalk)
- ? (Flags & DwarfLinkerForBinary::TF_ODR)
- : CU.hasODR();
- DWARFUnit &Unit = CU.getOrigUnit();
- DWARFDataExtractor Data = Unit.getDebugInfoExtractor();
- const auto *Abbrev = Die.getAbbreviationDeclarationPtr();
- uint64_t Offset = Die.getOffset() + getULEB128Size(Abbrev->getCode());
-
- SmallVector<std::pair<DWARFDie, CompileUnit &>, 4> ReferencedDIEs;
- for (const auto &AttrSpec : Abbrev->attributes()) {
- DWARFFormValue Val(AttrSpec.Form);
- if (!Val.isFormClass(DWARFFormValue::FC_Reference) ||
- AttrSpec.Attr == dwarf::DW_AT_sibling) {
- DWARFFormValue::skipValue(AttrSpec.Form, Data, &Offset,
- Unit.getFormParams());
- continue;
- }
-
- Val.extractValue(Data, &Offset, Unit.getFormParams(), &Unit);
- CompileUnit *ReferencedCU;
- if (auto RefDie =
- resolveDIEReference(Linker, DMO, Units, Val, Die, ReferencedCU)) {
- uint32_t RefIdx = ReferencedCU->getOrigUnit().getDIEIndex(RefDie);
- CompileUnit::DIEInfo &Info = ReferencedCU->getInfo(RefIdx);
- bool IsModuleRef = Info.Ctxt && Info.Ctxt->getCanonicalDIEOffset() &&
- Info.Ctxt->isDefinedInClangModule();
- // If the referenced DIE has a DeclContext that has already been
- // emitted, then do not keep the one in this CU. We'll link to
- // the canonical DIE in cloneDieReferenceAttribute.
- //
- // FIXME: compatibility with dsymutil-classic. UseODR shouldn't
- // be necessary and could be advantageously replaced by
- // ReferencedCU->hasODR() && CU.hasODR().
- //
- // FIXME: compatibility with dsymutil-classic. There is no
- // reason not to unique ref_addr references.
- if (AttrSpec.Form != dwarf::DW_FORM_ref_addr && (UseOdr || IsModuleRef) &&
- Info.Ctxt &&
- Info.Ctxt != ReferencedCU->getInfo(Info.ParentIdx).Ctxt &&
- Info.Ctxt->getCanonicalDIEOffset() && isODRAttribute(AttrSpec.Attr))
- continue;
-
- // Keep a module forward declaration if there is no definition.
- if (!(isODRAttribute(AttrSpec.Attr) && Info.Ctxt &&
- Info.Ctxt->getCanonicalDIEOffset()))
- Info.Prune = false;
- ReferencedDIEs.emplace_back(RefDie, *ReferencedCU);
- }
- }
-
- unsigned ODRFlag = UseOdr ? DwarfLinkerForBinary::TF_ODR : 0;
-
- // Add referenced DIEs in reverse order to the worklist to effectively
- // process them in order.
- for (auto &P : reverse(ReferencedDIEs)) {
- // Add a worklist item before every child to calculate incompleteness right
- // after the current child is processed.
- uint32_t RefIdx = P.second.getOrigUnit().getDIEIndex(P.first);
- CompileUnit::DIEInfo &Info = P.second.getInfo(RefIdx);
- Worklist.emplace_back(Die, CU, WorklistItemType::UpdateRefIncompleteness,
- &Info);
- Worklist.emplace_back(P.first, P.second,
- DwarfLinkerForBinary::TF_Keep |
- DwarfLinkerForBinary::TF_DependencyWalk |
- ODRFlag);
- }
-}
-
-/// Look at the parent of the given DIE and decide whether they should be kept.
-static void lookForParentDIEsToKeep(unsigned AncestorIdx, CompileUnit &CU,
- unsigned Flags,
- SmallVectorImpl<WorklistItem> &Worklist) {
- // Stop if we encounter an ancestor that's already marked as kept.
- if (CU.getInfo(AncestorIdx).Keep)
- return;
-
- DWARFUnit &Unit = CU.getOrigUnit();
- DWARFDie ParentDIE = Unit.getDIEAtIndex(AncestorIdx);
- Worklist.emplace_back(CU.getInfo(AncestorIdx).ParentIdx, CU, Flags);
- Worklist.emplace_back(ParentDIE, CU, Flags);
-}
-
-/// Recursively walk the \p DIE tree and look for DIEs to keep. Store that
-/// information in \p CU's DIEInfo.
-///
-/// This function is the entry point of the DIE selection algorithm. It is
-/// expected to walk the DIE tree in file order and (though the mediation of
-/// its helper) call hasValidRelocation() on each DIE that might be a 'root
-/// DIE' (See DwarfLinker class comment).
-///
-/// While walking the dependencies of root DIEs, this function is also called,
-/// but during these dependency walks the file order is not respected. The
-/// TF_DependencyWalk flag tells us which kind of traversal we are currently
-/// doing.
-///
-/// The recursive algorithm is implemented iteratively as a work list because
-/// very deep recursion could exhaust the stack for large projects. The work
-/// list acts as a scheduler for
diff erent types of work that need to be
-/// performed.
-///
-/// The recursive nature of the algorithm is simulated by running the "main"
-/// algorithm (LookForDIEsToKeep) followed by either looking at more DIEs
-/// (LookForChildDIEsToKeep, LookForRefDIEsToKeep, LookForParentDIEsToKeep) or
-/// fixing up a computed property (UpdateChildIncompleteness,
-/// UpdateRefIncompleteness).
-///
-/// The return value indicates whether the DIE is incomplete.
-void DwarfLinkerForBinary::lookForDIEsToKeep(RelocationManager &RelocMgr,
- RangesTy &Ranges,
- const UnitListTy &Units,
- const DWARFDie &Die,
- const DebugMapObject &DMO,
- CompileUnit &Cu, unsigned Flags) {
- // LIFO work list.
- SmallVector<WorklistItem, 4> Worklist;
- Worklist.emplace_back(Die, Cu, Flags);
-
- while (!Worklist.empty()) {
- WorklistItem Current = Worklist.back();
- Worklist.pop_back();
-
- // Look at the worklist type to decide what kind of work to perform.
- switch (Current.Type) {
- case WorklistItemType::UpdateChildIncompleteness:
- updateChildIncompleteness(Current.Die, Current.CU, *Current.OtherInfo);
- continue;
- case WorklistItemType::UpdateRefIncompleteness:
- updateRefIncompleteness(Current.Die, Current.CU, *Current.OtherInfo);
- continue;
- case WorklistItemType::LookForChildDIEsToKeep:
- lookForChildDIEsToKeep(Current.Die, Current.CU, Current.Flags, Worklist);
- continue;
- case WorklistItemType::LookForRefDIEsToKeep:
- lookForRefDIEsToKeep(Current.Die, Current.CU, Current.Flags, *this, Units,
- DMO, Worklist);
- continue;
- case WorklistItemType::LookForParentDIEsToKeep:
- lookForParentDIEsToKeep(Current.AncestorIdx, Current.CU, Current.Flags,
- Worklist);
- continue;
- case WorklistItemType::LookForDIEsToKeep:
- break;
- }
-
- unsigned Idx = Current.CU.getOrigUnit().getDIEIndex(Current.Die);
- CompileUnit::DIEInfo &MyInfo = Current.CU.getInfo(Idx);
-
- if (MyInfo.Prune)
- continue;
-
- // If the Keep flag is set, we are marking a required DIE's dependencies.
- // If our target is already marked as kept, we're all set.
- bool AlreadyKept = MyInfo.Keep;
- if ((Current.Flags & TF_DependencyWalk) && AlreadyKept)
- continue;
-
- // We must not call shouldKeepDIE while called from keepDIEAndDependencies,
- // because it would screw up the relocation finding logic.
- if (!(Current.Flags & TF_DependencyWalk))
- Current.Flags = shouldKeepDIE(RelocMgr, Ranges, Current.Die, DMO,
- Current.CU, MyInfo, Current.Flags);
-
- // Finish by looking for child DIEs. Because of the LIFO worklist we need
- // to schedule that work before any subsequent items are added to the
- // worklist.
- Worklist.emplace_back(Current.Die, Current.CU, Current.Flags,
- WorklistItemType::LookForChildDIEsToKeep);
-
- if (AlreadyKept || !(Current.Flags & TF_Keep))
- continue;
-
- // If it is a newly kept DIE mark it as well as all its dependencies as
- // kept.
- MyInfo.Keep = true;
-
- // We're looking for incomplete types.
- MyInfo.Incomplete =
- Current.Die.getTag() != dwarf::DW_TAG_subprogram &&
- Current.Die.getTag() != dwarf::DW_TAG_member &&
- dwarf::toUnsigned(Current.Die.find(dwarf::DW_AT_declaration), 0);
-
- // After looking at the parent chain, look for referenced DIEs. Because of
- // the LIFO worklist we need to schedule that work before any subsequent
- // items are added to the worklist.
- Worklist.emplace_back(Current.Die, Current.CU, Current.Flags,
- WorklistItemType::LookForRefDIEsToKeep);
-
- bool UseOdr = (Current.Flags & TF_DependencyWalk) ? (Current.Flags & TF_ODR)
- : Current.CU.hasODR();
- unsigned ODRFlag = UseOdr ? TF_ODR : 0;
- unsigned ParFlags = TF_ParentWalk | TF_Keep | TF_DependencyWalk | ODRFlag;
-
- // Now schedule the parent walk.
- Worklist.emplace_back(MyInfo.ParentIdx, Current.CU, ParFlags);
- }
-}
-
-/// Assign an abbreviation number to \p Abbrev.
-///
-/// Our DIEs get freed after every DebugMapObject has been processed,
-/// thus the FoldingSet we use to unique DIEAbbrevs cannot refer to
-/// the instances hold by the DIEs. When we encounter an abbreviation
-/// that we don't know, we create a permanent copy of it.
-void DwarfLinkerForBinary::assignAbbrev(DIEAbbrev &Abbrev) {
- // Check the set for priors.
- FoldingSetNodeID ID;
- Abbrev.Profile(ID);
- void *InsertToken;
- DIEAbbrev *InSet = AbbreviationsSet.FindNodeOrInsertPos(ID, InsertToken);
-
- // If it's newly added.
- if (InSet) {
- // Assign existing abbreviation number.
- Abbrev.setNumber(InSet->getNumber());
- } else {
- // Add to abbreviation list.
- Abbreviations.push_back(
- std::make_unique<DIEAbbrev>(Abbrev.getTag(), Abbrev.hasChildren()));
- for (const auto &Attr : Abbrev.getData())
- Abbreviations.back()->AddAttribute(Attr.getAttribute(), Attr.getForm());
- AbbreviationsSet.InsertNode(Abbreviations.back().get(), InsertToken);
- // Assign the unique abbreviation number.
- Abbrev.setNumber(Abbreviations.size());
- Abbreviations.back()->setNumber(Abbreviations.size());
- }
-}
-
-unsigned DwarfLinkerForBinary::DIECloner::cloneStringAttribute(
- DIE &Die, AttributeSpec AttrSpec, const DWARFFormValue &Val,
- const DWARFUnit &U, OffsetsStringPool &StringPool, AttributesInfo &Info) {
- // Switch everything to out of line strings.
- const char *String = *Val.getAsCString();
- auto StringEntry = StringPool.getEntry(String);
-
- // Update attributes info.
- if (AttrSpec.Attr == dwarf::DW_AT_name)
- Info.Name = StringEntry;
- else if (AttrSpec.Attr == dwarf::DW_AT_MIPS_linkage_name ||
- AttrSpec.Attr == dwarf::DW_AT_linkage_name)
- Info.MangledName = StringEntry;
-
- Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr), dwarf::DW_FORM_strp,
- DIEInteger(StringEntry.getOffset()));
-
- return 4;
-}
-
-unsigned DwarfLinkerForBinary::DIECloner::cloneDieReferenceAttribute(
- DIE &Die, const DWARFDie &InputDIE, AttributeSpec AttrSpec,
- unsigned AttrSize, const DWARFFormValue &Val, const DebugMapObject &DMO,
- CompileUnit &Unit) {
- const DWARFUnit &U = Unit.getOrigUnit();
- uint64_t Ref = *Val.getAsReference();
- DIE *NewRefDie = nullptr;
- CompileUnit *RefUnit = nullptr;
- DeclContext *Ctxt = nullptr;
-
- DWARFDie RefDie =
- resolveDIEReference(Linker, DMO, CompileUnits, Val, InputDIE, RefUnit);
-
- // If the referenced DIE is not found, drop the attribute.
- if (!RefDie || AttrSpec.Attr == dwarf::DW_AT_sibling)
- return 0;
-
- unsigned Idx = RefUnit->getOrigUnit().getDIEIndex(RefDie);
- CompileUnit::DIEInfo &RefInfo = RefUnit->getInfo(Idx);
-
- // If we already have emitted an equivalent DeclContext, just point
- // at it.
- if (isODRAttribute(AttrSpec.Attr)) {
- Ctxt = RefInfo.Ctxt;
- if (Ctxt && Ctxt->getCanonicalDIEOffset()) {
- DIEInteger Attr(Ctxt->getCanonicalDIEOffset());
- Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
- dwarf::DW_FORM_ref_addr, Attr);
- return U.getRefAddrByteSize();
- }
- }
-
- if (!RefInfo.Clone) {
- assert(Ref > InputDIE.getOffset());
- // We haven't cloned this DIE yet. Just create an empty one and
- // store it. It'll get really cloned when we process it.
- RefInfo.Clone = DIE::get(DIEAlloc, dwarf::Tag(RefDie.getTag()));
- }
- NewRefDie = RefInfo.Clone;
-
- if (AttrSpec.Form == dwarf::DW_FORM_ref_addr ||
- (Unit.hasODR() && isODRAttribute(AttrSpec.Attr))) {
- // We cannot currently rely on a DIEEntry to emit ref_addr
- // references, because the implementation calls back to DwarfDebug
- // to find the unit offset. (We don't have a DwarfDebug)
- // FIXME: we should be able to design DIEEntry reliance on
- // DwarfDebug away.
- uint64_t Attr;
- if (Ref < InputDIE.getOffset()) {
- // We must have already cloned that DIE.
- uint32_t NewRefOffset =
- RefUnit->getStartOffset() + NewRefDie->getOffset();
- Attr = NewRefOffset;
- Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
- dwarf::DW_FORM_ref_addr, DIEInteger(Attr));
- } else {
- // A forward reference. Note and fixup later.
- Attr = 0xBADDEF;
- Unit.noteForwardReference(
- NewRefDie, RefUnit, Ctxt,
- Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
- dwarf::DW_FORM_ref_addr, DIEInteger(Attr)));
- }
- return U.getRefAddrByteSize();
- }
-
- Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
- dwarf::Form(AttrSpec.Form), DIEEntry(*NewRefDie));
- return AttrSize;
-}
-
-void DwarfLinkerForBinary::DIECloner::cloneExpression(
- DataExtractor &Data, DWARFExpression Expression, const DebugMapObject &DMO,
- CompileUnit &Unit, SmallVectorImpl<uint8_t> &OutputBuffer) {
- using Encoding = DWARFExpression::Operation::Encoding;
-
- uint64_t OpOffset = 0;
- for (auto &Op : Expression) {
- auto Description = Op.getDescription();
- // DW_OP_const_type is variable-length and has 3
- // operands. DWARFExpression thus far only supports 2.
- auto Op0 = Description.Op[0];
- auto Op1 = Description.Op[1];
- if ((Op0 == Encoding::BaseTypeRef && Op1 != Encoding::SizeNA) ||
- (Op1 == Encoding::BaseTypeRef && Op0 != Encoding::Size1))
- Linker.reportWarning("Unsupported DW_OP encoding.", DMO);
-
- if ((Op0 == Encoding::BaseTypeRef && Op1 == Encoding::SizeNA) ||
- (Op1 == Encoding::BaseTypeRef && Op0 == Encoding::Size1)) {
- // This code assumes that the other non-typeref operand fits into 1 byte.
- assert(OpOffset < Op.getEndOffset());
- uint32_t ULEBsize = Op.getEndOffset() - OpOffset - 1;
- assert(ULEBsize <= 16);
-
- // Copy over the operation.
- OutputBuffer.push_back(Op.getCode());
- uint64_t RefOffset;
- if (Op1 == Encoding::SizeNA) {
- RefOffset = Op.getRawOperand(0);
- } else {
- OutputBuffer.push_back(Op.getRawOperand(0));
- RefOffset = Op.getRawOperand(1);
- }
- auto RefDie = Unit.getOrigUnit().getDIEForOffset(RefOffset);
- uint32_t RefIdx = Unit.getOrigUnit().getDIEIndex(RefDie);
- CompileUnit::DIEInfo &Info = Unit.getInfo(RefIdx);
- uint32_t Offset = 0;
- if (DIE *Clone = Info.Clone)
- Offset = Clone->getOffset();
- else
- Linker.reportWarning("base type ref doesn't point to DW_TAG_base_type.",
- DMO);
- uint8_t ULEB[16];
- unsigned RealSize = encodeULEB128(Offset, ULEB, ULEBsize);
- if (RealSize > ULEBsize) {
- // Emit the generic type as a fallback.
- RealSize = encodeULEB128(0, ULEB, ULEBsize);
- Linker.reportWarning("base type ref doesn't fit.", DMO);
- }
- assert(RealSize == ULEBsize && "padding failed");
- ArrayRef<uint8_t> ULEBbytes(ULEB, ULEBsize);
- OutputBuffer.append(ULEBbytes.begin(), ULEBbytes.end());
- } else {
- // Copy over everything else unmodified.
- StringRef Bytes = Data.getData().slice(OpOffset, Op.getEndOffset());
- OutputBuffer.append(Bytes.begin(), Bytes.end());
- }
- OpOffset = Op.getEndOffset();
- }
-}
-
-unsigned DwarfLinkerForBinary::DIECloner::cloneBlockAttribute(
- DIE &Die, const DebugMapObject &DMO, CompileUnit &Unit,
- AttributeSpec AttrSpec, const DWARFFormValue &Val, unsigned AttrSize,
- bool IsLittleEndian) {
- DIEValueList *Attr;
- DIEValue Value;
- DIELoc *Loc = nullptr;
- DIEBlock *Block = nullptr;
- if (AttrSpec.Form == dwarf::DW_FORM_exprloc) {
- Loc = new (DIEAlloc) DIELoc;
- Linker.DIELocs.push_back(Loc);
- } else {
- Block = new (DIEAlloc) DIEBlock;
- Linker.DIEBlocks.push_back(Block);
- }
- Attr = Loc ? static_cast<DIEValueList *>(Loc)
- : static_cast<DIEValueList *>(Block);
-
- if (Loc)
- Value = DIEValue(dwarf::Attribute(AttrSpec.Attr),
- dwarf::Form(AttrSpec.Form), Loc);
- else
- Value = DIEValue(dwarf::Attribute(AttrSpec.Attr),
- dwarf::Form(AttrSpec.Form), Block);
-
- // If the block is a DWARF Expression, clone it into the temporary
- // buffer using cloneExpression(), otherwise copy the data directly.
- SmallVector<uint8_t, 32> Buffer;
- ArrayRef<uint8_t> Bytes = *Val.getAsBlock();
- if (DWARFAttribute::mayHaveLocationDescription(AttrSpec.Attr) &&
- (Val.isFormClass(DWARFFormValue::FC_Block) ||
- Val.isFormClass(DWARFFormValue::FC_Exprloc))) {
- DWARFUnit &OrigUnit = Unit.getOrigUnit();
- DataExtractor Data(StringRef((const char *)Bytes.data(), Bytes.size()),
- IsLittleEndian, OrigUnit.getAddressByteSize());
- DWARFExpression Expr(Data, OrigUnit.getVersion(),
- OrigUnit.getAddressByteSize());
- cloneExpression(Data, Expr, DMO, Unit, Buffer);
- Bytes = Buffer;
- }
- for (auto Byte : Bytes)
- Attr->addValue(DIEAlloc, static_cast<dwarf::Attribute>(0),
- dwarf::DW_FORM_data1, DIEInteger(Byte));
-
- // FIXME: If DIEBlock and DIELoc just reuses the Size field of
- // the DIE class, this if could be replaced by
- // Attr->setSize(Bytes.size()).
- if (Linker.Streamer) {
- auto *AsmPrinter = &Linker.Streamer->getAsmPrinter();
- if (Loc)
- Loc->ComputeSize(AsmPrinter);
- else
- Block->ComputeSize(AsmPrinter);
- }
- Die.addValue(DIEAlloc, Value);
- return AttrSize;
-}
-
-unsigned DwarfLinkerForBinary::DIECloner::cloneAddressAttribute(
- DIE &Die, AttributeSpec AttrSpec, const DWARFFormValue &Val,
- const CompileUnit &Unit, AttributesInfo &Info) {
- uint64_t Addr = *Val.getAsAddress();
-
- if (LLVM_UNLIKELY(Linker.Options.Update)) {
- if (AttrSpec.Attr == dwarf::DW_AT_low_pc)
- Info.HasLowPc = true;
- Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
- dwarf::Form(AttrSpec.Form), DIEInteger(Addr));
- return Unit.getOrigUnit().getAddressByteSize();
- }
-
- if (AttrSpec.Attr == dwarf::DW_AT_low_pc) {
- if (Die.getTag() == dwarf::DW_TAG_inlined_subroutine ||
- Die.getTag() == dwarf::DW_TAG_lexical_block)
- // The low_pc of a block or inline subroutine might get
- // relocated because it happens to match the low_pc of the
- // enclosing subprogram. To prevent issues with that, always use
- // the low_pc from the input DIE if relocations have been applied.
- Addr = (Info.OrigLowPc != std::numeric_limits<uint64_t>::max()
- ? Info.OrigLowPc
- : Addr) +
- Info.PCOffset;
- else if (Die.getTag() == dwarf::DW_TAG_compile_unit) {
- Addr = Unit.getLowPc();
- if (Addr == std::numeric_limits<uint64_t>::max())
- return 0;
- }
- Info.HasLowPc = true;
- } else if (AttrSpec.Attr == dwarf::DW_AT_high_pc) {
- if (Die.getTag() == dwarf::DW_TAG_compile_unit) {
- if (uint64_t HighPc = Unit.getHighPc())
- Addr = HighPc;
- else
- return 0;
- } else
- // If we have a high_pc recorded for the input DIE, use
- // it. Otherwise (when no relocations where applied) just use the
- // one we just decoded.
- Addr = (Info.OrigHighPc ? Info.OrigHighPc : Addr) + Info.PCOffset;
- } else if (AttrSpec.Attr == dwarf::DW_AT_call_return_pc) {
- // Relocate a return PC address within a call site entry.
- if (Die.getTag() == dwarf::DW_TAG_call_site)
- Addr += Info.PCOffset;
- }
-
- Die.addValue(DIEAlloc, static_cast<dwarf::Attribute>(AttrSpec.Attr),
- static_cast<dwarf::Form>(AttrSpec.Form), DIEInteger(Addr));
- return Unit.getOrigUnit().getAddressByteSize();
-}
-
-unsigned DwarfLinkerForBinary::DIECloner::cloneScalarAttribute(
- DIE &Die, const DWARFDie &InputDIE, const DebugMapObject &DMO,
- CompileUnit &Unit, AttributeSpec AttrSpec, const DWARFFormValue &Val,
- unsigned AttrSize, AttributesInfo &Info) {
- uint64_t Value;
-
- if (LLVM_UNLIKELY(Linker.Options.Update)) {
- if (auto OptionalValue = Val.getAsUnsignedConstant())
- Value = *OptionalValue;
- else if (auto OptionalValue = Val.getAsSignedConstant())
- Value = *OptionalValue;
- else if (auto OptionalValue = Val.getAsSectionOffset())
- Value = *OptionalValue;
- else {
- Linker.reportWarning(
- "Unsupported scalar attribute form. Dropping attribute.", DMO,
- &InputDIE);
- return 0;
- }
- if (AttrSpec.Attr == dwarf::DW_AT_declaration && Value)
- Info.IsDeclaration = true;
- Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
- dwarf::Form(AttrSpec.Form), DIEInteger(Value));
- return AttrSize;
- }
-
- if (AttrSpec.Attr == dwarf::DW_AT_high_pc &&
- Die.getTag() == dwarf::DW_TAG_compile_unit) {
- if (Unit.getLowPc() == -1ULL)
- return 0;
- // Dwarf >= 4 high_pc is an size, not an address.
- Value = Unit.getHighPc() - Unit.getLowPc();
- } else if (AttrSpec.Form == dwarf::DW_FORM_sec_offset)
- Value = *Val.getAsSectionOffset();
- else if (AttrSpec.Form == dwarf::DW_FORM_sdata)
- Value = *Val.getAsSignedConstant();
- else if (auto OptionalValue = Val.getAsUnsignedConstant())
- Value = *OptionalValue;
- else {
- Linker.reportWarning(
- "Unsupported scalar attribute form. Dropping attribute.", DMO,
- &InputDIE);
- return 0;
- }
- PatchLocation Patch =
- Die.addValue(DIEAlloc, dwarf::Attribute(AttrSpec.Attr),
- dwarf::Form(AttrSpec.Form), DIEInteger(Value));
- if (AttrSpec.Attr == dwarf::DW_AT_ranges) {
- Unit.noteRangeAttribute(Die, Patch);
- Info.HasRanges = true;
- }
-
- // A more generic way to check for location attributes would be
- // nice, but it's very unlikely that any other attribute needs a
- // location list.
- // FIXME: use DWARFAttribute::mayHaveLocationDescription().
- else if (AttrSpec.Attr == dwarf::DW_AT_location ||
- AttrSpec.Attr == dwarf::DW_AT_frame_base)
- Unit.noteLocationAttribute(Patch, Info.PCOffset);
- else if (AttrSpec.Attr == dwarf::DW_AT_declaration && Value)
- Info.IsDeclaration = true;
-
- return AttrSize;
-}
-
-/// Clone \p InputDIE's attribute described by \p AttrSpec with
-/// value \p Val, and add it to \p Die.
-/// \returns the size of the cloned attribute.
-unsigned DwarfLinkerForBinary::DIECloner::cloneAttribute(
- DIE &Die, const DWARFDie &InputDIE, const DebugMapObject &DMO,
- CompileUnit &Unit, OffsetsStringPool &StringPool, const DWARFFormValue &Val,
- const AttributeSpec AttrSpec, unsigned AttrSize, AttributesInfo &Info,
- bool IsLittleEndian) {
- const DWARFUnit &U = Unit.getOrigUnit();
-
- switch (AttrSpec.Form) {
- case dwarf::DW_FORM_strp:
- case dwarf::DW_FORM_string:
- return cloneStringAttribute(Die, AttrSpec, Val, U, StringPool, Info);
- case dwarf::DW_FORM_ref_addr:
- case dwarf::DW_FORM_ref1:
- case dwarf::DW_FORM_ref2:
- case dwarf::DW_FORM_ref4:
- case dwarf::DW_FORM_ref8:
- return cloneDieReferenceAttribute(Die, InputDIE, AttrSpec, AttrSize, Val,
- DMO, Unit);
- case dwarf::DW_FORM_block:
- case dwarf::DW_FORM_block1:
- case dwarf::DW_FORM_block2:
- case dwarf::DW_FORM_block4:
- case dwarf::DW_FORM_exprloc:
- return cloneBlockAttribute(Die, DMO, Unit, AttrSpec, Val, AttrSize,
- IsLittleEndian);
- case dwarf::DW_FORM_addr:
- return cloneAddressAttribute(Die, AttrSpec, Val, Unit, Info);
- case dwarf::DW_FORM_data1:
- case dwarf::DW_FORM_data2:
- case dwarf::DW_FORM_data4:
- case dwarf::DW_FORM_data8:
- case dwarf::DW_FORM_udata:
- case dwarf::DW_FORM_sdata:
- case dwarf::DW_FORM_sec_offset:
- case dwarf::DW_FORM_flag:
- case dwarf::DW_FORM_flag_present:
- return cloneScalarAttribute(Die, InputDIE, DMO, Unit, AttrSpec, Val,
- AttrSize, Info);
- default:
- Linker.reportWarning(
- "Unsupported attribute form in cloneAttribute. Dropping.", DMO,
- &InputDIE);
- }
-
- return 0;
-}
-
-/// Apply the valid relocations found by findValidRelocs() to
-/// the buffer \p Data, taking into account that Data is at \p BaseOffset
-/// in the debug_info section.
-///
-/// Like for findValidRelocs(), this function must be called with
-/// monotonic \p BaseOffset values.
-///
-/// \returns whether any reloc has been applied.
-bool DwarfLinkerForBinary::RelocationManager::applyValidRelocs(
- MutableArrayRef<char> Data, uint64_t BaseOffset, bool IsLittleEndian) {
- assert((NextValidReloc == 0 ||
- BaseOffset > ValidRelocs[NextValidReloc - 1].Offset) &&
- "BaseOffset should only be increasing.");
- if (NextValidReloc >= ValidRelocs.size())
- return false;
-
- // Skip relocs that haven't been applied.
- while (NextValidReloc < ValidRelocs.size() &&
- ValidRelocs[NextValidReloc].Offset < BaseOffset)
- ++NextValidReloc;
-
- bool Applied = false;
- uint64_t EndOffset = BaseOffset + Data.size();
- while (NextValidReloc < ValidRelocs.size() &&
- ValidRelocs[NextValidReloc].Offset >= BaseOffset &&
- ValidRelocs[NextValidReloc].Offset < EndOffset) {
- const auto &ValidReloc = ValidRelocs[NextValidReloc++];
- assert(ValidReloc.Offset - BaseOffset < Data.size());
- assert(ValidReloc.Offset - BaseOffset + ValidReloc.Size <= Data.size());
- char Buf[8];
- uint64_t Value = ValidReloc.Mapping->getValue().BinaryAddress;
- Value += ValidReloc.Addend;
- for (unsigned i = 0; i != ValidReloc.Size; ++i) {
- unsigned Index = IsLittleEndian ? i : (ValidReloc.Size - i - 1);
- Buf[i] = uint8_t(Value >> (Index * 8));
- }
- assert(ValidReloc.Size <= sizeof(Buf));
- memcpy(&Data[ValidReloc.Offset - BaseOffset], Buf, ValidReloc.Size);
- Applied = true;
- }
-
- return Applied;
-}
-
-static bool isObjCSelector(StringRef Name) {
- return Name.size() > 2 && (Name[0] == '-' || Name[0] == '+') &&
- (Name[1] == '[');
-}
-
-void DwarfLinkerForBinary::DIECloner::addObjCAccelerator(
- CompileUnit &Unit, const DIE *Die, DwarfStringPoolEntryRef Name,
- OffsetsStringPool &StringPool, bool SkipPubSection) {
- assert(isObjCSelector(Name.getString()) && "not an objc selector");
- // Objective C method or class function.
- // "- [Class(Category) selector :withArg ...]"
- StringRef ClassNameStart(Name.getString().drop_front(2));
- size_t FirstSpace = ClassNameStart.find(' ');
- if (FirstSpace == StringRef::npos)
- return;
-
- StringRef SelectorStart(ClassNameStart.data() + FirstSpace + 1);
- if (!SelectorStart.size())
- return;
-
- StringRef Selector(SelectorStart.data(), SelectorStart.size() - 1);
- Unit.addNameAccelerator(Die, StringPool.getEntry(Selector), SkipPubSection);
-
- // Add an entry for the class name that points to this
- // method/class function.
- StringRef ClassName(ClassNameStart.data(), FirstSpace);
- Unit.addObjCAccelerator(Die, StringPool.getEntry(ClassName), SkipPubSection);
-
- if (ClassName[ClassName.size() - 1] == ')') {
- size_t OpenParens = ClassName.find('(');
- if (OpenParens != StringRef::npos) {
- StringRef ClassNameNoCategory(ClassName.data(), OpenParens);
- Unit.addObjCAccelerator(Die, StringPool.getEntry(ClassNameNoCategory),
- SkipPubSection);
-
- std::string MethodNameNoCategory(Name.getString().data(), OpenParens + 2);
- // FIXME: The missing space here may be a bug, but
- // dsymutil-classic also does it this way.
- MethodNameNoCategory.append(SelectorStart);
- Unit.addNameAccelerator(Die, StringPool.getEntry(MethodNameNoCategory),
- SkipPubSection);
- }
- }
-}
-
-static bool
-shouldSkipAttribute(DWARFAbbreviationDeclaration::AttributeSpec AttrSpec,
- uint16_t Tag, bool InDebugMap, bool SkipPC,
- bool InFunctionScope) {
- switch (AttrSpec.Attr) {
- default:
- return false;
- case dwarf::DW_AT_low_pc:
- case dwarf::DW_AT_high_pc:
- case dwarf::DW_AT_ranges:
- return SkipPC;
- case dwarf::DW_AT_location:
- case dwarf::DW_AT_frame_base:
- // FIXME: for some reason dsymutil-classic keeps the location attributes
- // when they are of block type (i.e. not location lists). This is totally
- // wrong for globals where we will keep a wrong address. It is mostly
- // harmless for locals, but there is no point in keeping these anyway when
- // the function wasn't linked.
- return (SkipPC || (!InFunctionScope && Tag == dwarf::DW_TAG_variable &&
- !InDebugMap)) &&
- !DWARFFormValue(AttrSpec.Form).isFormClass(DWARFFormValue::FC_Block);
- }
-}
-
-DIE *DwarfLinkerForBinary::DIECloner::cloneDIE(
- const DWARFDie &InputDIE, const DebugMapObject &DMO, CompileUnit &Unit,
- OffsetsStringPool &StringPool, int64_t PCOffset, uint32_t OutOffset,
- unsigned Flags, bool IsLittleEndian, DIE *Die) {
- DWARFUnit &U = Unit.getOrigUnit();
- unsigned Idx = U.getDIEIndex(InputDIE);
- CompileUnit::DIEInfo &Info = Unit.getInfo(Idx);
-
- // Should the DIE appear in the output?
- if (!Unit.getInfo(Idx).Keep)
- return nullptr;
-
- uint64_t Offset = InputDIE.getOffset();
- assert(!(Die && Info.Clone) && "Can't supply a DIE and a cloned DIE");
- if (!Die) {
- // The DIE might have been already created by a forward reference
- // (see cloneDieReferenceAttribute()).
- if (!Info.Clone)
- Info.Clone = DIE::get(DIEAlloc, dwarf::Tag(InputDIE.getTag()));
- Die = Info.Clone;
- }
-
- assert(Die->getTag() == InputDIE.getTag());
- Die->setOffset(OutOffset);
- if ((Unit.hasODR() || Unit.isClangModule()) && !Info.Incomplete &&
- Die->getTag() != dwarf::DW_TAG_namespace && Info.Ctxt &&
- Info.Ctxt != Unit.getInfo(Info.ParentIdx).Ctxt &&
- !Info.Ctxt->getCanonicalDIEOffset()) {
- // We are about to emit a DIE that is the root of its own valid
- // DeclContext tree. Make the current offset the canonical offset
- // for this context.
- Info.Ctxt->setCanonicalDIEOffset(OutOffset + Unit.getStartOffset());
- }
-
- // Extract and clone every attribute.
- DWARFDataExtractor Data = U.getDebugInfoExtractor();
- // Point to the next DIE (generally there is always at least a NULL
- // entry after the current one). If this is a lone
- // DW_TAG_compile_unit without any children, point to the next unit.
- uint64_t NextOffset = (Idx + 1 < U.getNumDIEs())
- ? U.getDIEAtIndex(Idx + 1).getOffset()
- : U.getNextUnitOffset();
- AttributesInfo AttrInfo;
-
- // We could copy the data only if we need to apply a relocation to it. After
- // testing, it seems there is no performance downside to doing the copy
- // unconditionally, and it makes the code simpler.
- SmallString<40> DIECopy(Data.getData().substr(Offset, NextOffset - Offset));
- Data =
- DWARFDataExtractor(DIECopy, Data.isLittleEndian(), Data.getAddressSize());
- // Modify the copy with relocated addresses.
- if (RelocMgr.areRelocationsResolved() &&
- RelocMgr.applyValidRelocs(DIECopy, Offset, Data.isLittleEndian())) {
- // If we applied relocations, we store the value of high_pc that was
- // potentially stored in the input DIE. If high_pc is an address
- // (Dwarf version == 2), then it might have been relocated to a
- // totally unrelated value (because the end address in the object
- // file might be start address of another function which got moved
- // independently by the linker). The computation of the actual
- // high_pc value is done in cloneAddressAttribute().
- AttrInfo.OrigHighPc =
- dwarf::toAddress(InputDIE.find(dwarf::DW_AT_high_pc), 0);
- // Also store the low_pc. It might get relocated in an
- // inline_subprogram that happens at the beginning of its
- // inlining function.
- AttrInfo.OrigLowPc = dwarf::toAddress(InputDIE.find(dwarf::DW_AT_low_pc),
- std::numeric_limits<uint64_t>::max());
- }
-
- // Reset the Offset to 0 as we will be working on the local copy of
- // the data.
- Offset = 0;
-
- const auto *Abbrev = InputDIE.getAbbreviationDeclarationPtr();
- Offset += getULEB128Size(Abbrev->getCode());
-
- // We are entering a subprogram. Get and propagate the PCOffset.
- if (Die->getTag() == dwarf::DW_TAG_subprogram)
- PCOffset = Info.AddrAdjust;
- AttrInfo.PCOffset = PCOffset;
-
- if (Abbrev->getTag() == dwarf::DW_TAG_subprogram) {
- Flags |= TF_InFunctionScope;
- if (!Info.InDebugMap && LLVM_LIKELY(!Options.Update))
- Flags |= TF_SkipPC;
- }
-
- bool Copied = false;
- for (const auto &AttrSpec : Abbrev->attributes()) {
- if (LLVM_LIKELY(!Options.Update) &&
- shouldSkipAttribute(AttrSpec, Die->getTag(), Info.InDebugMap,
- Flags & TF_SkipPC, Flags & TF_InFunctionScope)) {
- DWARFFormValue::skipValue(AttrSpec.Form, Data, &Offset,
- U.getFormParams());
- // FIXME: dsymutil-classic keeps the old abbreviation around
- // even if it's not used. We can remove this (and the copyAbbrev
- // helper) as soon as bit-for-bit compatibility is not a goal anymore.
- if (!Copied) {
- copyAbbrev(*InputDIE.getAbbreviationDeclarationPtr(), Unit.hasODR());
- Copied = true;
- }
- continue;
- }
-
- DWARFFormValue Val(AttrSpec.Form);
- uint64_t AttrSize = Offset;
- Val.extractValue(Data, &Offset, U.getFormParams(), &U);
- AttrSize = Offset - AttrSize;
-
- OutOffset += cloneAttribute(*Die, InputDIE, DMO, Unit, StringPool, Val,
- AttrSpec, AttrSize, AttrInfo, IsLittleEndian);
- }
-
- // Look for accelerator entries.
- uint16_t Tag = InputDIE.getTag();
- // FIXME: This is slightly wrong. An inline_subroutine without a
- // low_pc, but with AT_ranges might be interesting to get into the
- // accelerator tables too. For now stick with dsymutil's behavior.
- if ((Info.InDebugMap || AttrInfo.HasLowPc || AttrInfo.HasRanges) &&
- Tag != dwarf::DW_TAG_compile_unit &&
- getDIENames(InputDIE, AttrInfo, StringPool,
- Tag != dwarf::DW_TAG_inlined_subroutine)) {
- if (AttrInfo.MangledName && AttrInfo.MangledName != AttrInfo.Name)
- Unit.addNameAccelerator(Die, AttrInfo.MangledName,
- Tag == dwarf::DW_TAG_inlined_subroutine);
- if (AttrInfo.Name) {
- if (AttrInfo.NameWithoutTemplate)
- Unit.addNameAccelerator(Die, AttrInfo.NameWithoutTemplate,
- /* SkipPubSection */ true);
- Unit.addNameAccelerator(Die, AttrInfo.Name,
- Tag == dwarf::DW_TAG_inlined_subroutine);
- }
- if (AttrInfo.Name && isObjCSelector(AttrInfo.Name.getString()))
- addObjCAccelerator(Unit, Die, AttrInfo.Name, StringPool,
- /* SkipPubSection =*/true);
-
- } else if (Tag == dwarf::DW_TAG_namespace) {
- if (!AttrInfo.Name)
- AttrInfo.Name = StringPool.getEntry("(anonymous namespace)");
- Unit.addNamespaceAccelerator(Die, AttrInfo.Name);
- } else if (isTypeTag(Tag) && !AttrInfo.IsDeclaration &&
- getDIENames(InputDIE, AttrInfo, StringPool) && AttrInfo.Name &&
- AttrInfo.Name.getString()[0]) {
- uint32_t Hash = hashFullyQualifiedName(InputDIE, Unit, DMO);
- uint64_t RuntimeLang =
- dwarf::toUnsigned(InputDIE.find(dwarf::DW_AT_APPLE_runtime_class))
- .getValueOr(0);
- bool ObjCClassIsImplementation =
- (RuntimeLang == dwarf::DW_LANG_ObjC ||
- RuntimeLang == dwarf::DW_LANG_ObjC_plus_plus) &&
- dwarf::toUnsigned(InputDIE.find(dwarf::DW_AT_APPLE_objc_complete_type))
- .getValueOr(0);
- Unit.addTypeAccelerator(Die, AttrInfo.Name, ObjCClassIsImplementation,
- Hash);
- }
-
- // Determine whether there are any children that we want to keep.
- bool HasChildren = false;
- for (auto Child : InputDIE.children()) {
- unsigned Idx = U.getDIEIndex(Child);
- if (Unit.getInfo(Idx).Keep) {
- HasChildren = true;
- break;
- }
- }
-
- DIEAbbrev NewAbbrev = Die->generateAbbrev();
- if (HasChildren)
- NewAbbrev.setChildrenFlag(dwarf::DW_CHILDREN_yes);
- // Assign a permanent abbrev number
- Linker.assignAbbrev(NewAbbrev);
- Die->setAbbrevNumber(NewAbbrev.getNumber());
-
- // Add the size of the abbreviation number to the output offset.
- OutOffset += getULEB128Size(Die->getAbbrevNumber());
-
- if (!HasChildren) {
- // Update our size.
- Die->setSize(OutOffset - Die->getOffset());
- return Die;
- }
-
- // Recursively clone children.
- for (auto Child : InputDIE.children()) {
- if (DIE *Clone = cloneDIE(Child, DMO, Unit, StringPool, PCOffset, OutOffset,
- Flags, IsLittleEndian)) {
- Die->addChild(Clone);
- OutOffset = Clone->getOffset() + Clone->getSize();
- }
- }
-
- // Account for the end of children marker.
- OutOffset += sizeof(int8_t);
- // Update our size.
- Die->setSize(OutOffset - Die->getOffset());
- return Die;
-}
-
-/// Patch the input object file relevant debug_ranges entries
-/// and emit them in the output file. Update the relevant attributes
-/// to point at the new entries.
-void DwarfLinkerForBinary::patchRangesForUnit(const CompileUnit &Unit,
- DWARFContext &OrigDwarf,
- const DebugMapObject &DMO) const {
- DWARFDebugRangeList RangeList;
- const auto &FunctionRanges = Unit.getFunctionRanges();
- unsigned AddressSize = Unit.getOrigUnit().getAddressByteSize();
- DWARFDataExtractor RangeExtractor(OrigDwarf.getDWARFObj(),
- OrigDwarf.getDWARFObj().getRangesSection(),
- OrigDwarf.isLittleEndian(), AddressSize);
- auto InvalidRange = FunctionRanges.end(), CurrRange = InvalidRange;
- DWARFUnit &OrigUnit = Unit.getOrigUnit();
- auto OrigUnitDie = OrigUnit.getUnitDIE(false);
- uint64_t OrigLowPc =
- dwarf::toAddress(OrigUnitDie.find(dwarf::DW_AT_low_pc), -1ULL);
- // Ranges addresses are based on the unit's low_pc. Compute the
- // offset we need to apply to adapt to the new unit's low_pc.
- int64_t UnitPcOffset = 0;
- if (OrigLowPc != -1ULL)
- UnitPcOffset = int64_t(OrigLowPc) - Unit.getLowPc();
-
- for (const auto &RangeAttribute : Unit.getRangesAttributes()) {
- uint64_t Offset = RangeAttribute.get();
- RangeAttribute.set(Streamer->getRangesSectionSize());
- if (Error E = RangeList.extract(RangeExtractor, &Offset)) {
- llvm::consumeError(std::move(E));
- reportWarning("invalid range list ignored.", DMO);
- RangeList.clear();
- }
- const auto &Entries = RangeList.getEntries();
- if (!Entries.empty()) {
- const DWARFDebugRangeList::RangeListEntry &First = Entries.front();
-
- if (CurrRange == InvalidRange ||
- First.StartAddress + OrigLowPc < CurrRange.start() ||
- First.StartAddress + OrigLowPc >= CurrRange.stop()) {
- CurrRange = FunctionRanges.find(First.StartAddress + OrigLowPc);
- if (CurrRange == InvalidRange ||
- CurrRange.start() > First.StartAddress + OrigLowPc) {
- reportWarning("no mapping for range.", DMO);
- continue;
- }
- }
- }
-
- Streamer->emitRangesEntries(UnitPcOffset, OrigLowPc, CurrRange, Entries,
- AddressSize);
- }
-}
-
-/// Generate the debug_aranges entries for \p Unit and if the
-/// unit has a DW_AT_ranges attribute, also emit the debug_ranges
-/// contribution for this attribute.
-/// FIXME: this could actually be done right in patchRangesForUnit,
-/// but for the sake of initial bit-for-bit compatibility with legacy
-/// dsymutil, we have to do it in a delayed pass.
-void DwarfLinkerForBinary::generateUnitRanges(CompileUnit &Unit) const {
- auto Attr = Unit.getUnitRangesAttribute();
- if (Attr)
- Attr->set(Streamer->getRangesSectionSize());
- Streamer->emitUnitRangesEntries(Unit, static_cast<bool>(Attr));
-}
-
-/// Insert the new line info sequence \p Seq into the current
-/// set of already linked line info \p Rows.
-static void insertLineSequence(std::vector<DWARFDebugLine::Row> &Seq,
- std::vector<DWARFDebugLine::Row> &Rows) {
- if (Seq.empty())
- return;
-
- if (!Rows.empty() && Rows.back().Address < Seq.front().Address) {
- Rows.insert(Rows.end(), Seq.begin(), Seq.end());
- Seq.clear();
- return;
- }
-
- object::SectionedAddress Front = Seq.front().Address;
- auto InsertPoint = partition_point(
- Rows, [=](const DWARFDebugLine::Row &O) { return O.Address < Front; });
-
- // FIXME: this only removes the unneeded end_sequence if the
- // sequences have been inserted in order. Using a global sort like
- // described in patchLineTableForUnit() and delaying the end_sequene
- // elimination to emitLineTableForUnit() we can get rid of all of them.
- if (InsertPoint != Rows.end() && InsertPoint->Address == Front &&
- InsertPoint->EndSequence) {
- *InsertPoint = Seq.front();
- Rows.insert(InsertPoint + 1, Seq.begin() + 1, Seq.end());
- } else {
- Rows.insert(InsertPoint, Seq.begin(), Seq.end());
- }
-
- Seq.clear();
-}
-
-static void patchStmtList(DIE &Die, DIEInteger Offset) {
- for (auto &V : Die.values())
- if (V.getAttribute() == dwarf::DW_AT_stmt_list) {
- V = DIEValue(V.getAttribute(), V.getForm(), Offset);
- return;
- }
-
- llvm_unreachable("Didn't find DW_AT_stmt_list in cloned DIE!");
-}
-
-/// Extract the line table for \p Unit from \p OrigDwarf, and
-/// recreate a relocated version of these for the address ranges that
-/// are present in the binary.
-void DwarfLinkerForBinary::patchLineTableForUnit(CompileUnit &Unit,
- DWARFContext &OrigDwarf,
- RangesTy &Ranges,
- const DebugMapObject &DMO) {
- DWARFDie CUDie = Unit.getOrigUnit().getUnitDIE();
- auto StmtList = dwarf::toSectionOffset(CUDie.find(dwarf::DW_AT_stmt_list));
- if (!StmtList)
- return;
-
- // Update the cloned DW_AT_stmt_list with the correct debug_line offset.
- if (auto *OutputDIE = Unit.getOutputUnitDIE())
- patchStmtList(*OutputDIE, DIEInteger(Streamer->getLineSectionSize()));
-
- // Parse the original line info for the unit.
- DWARFDebugLine::LineTable LineTable;
- uint64_t StmtOffset = *StmtList;
- DWARFDataExtractor LineExtractor(
- OrigDwarf.getDWARFObj(), OrigDwarf.getDWARFObj().getLineSection(),
- OrigDwarf.isLittleEndian(), Unit.getOrigUnit().getAddressByteSize());
- if (Options.Translator)
- return Streamer->translateLineTable(LineExtractor, StmtOffset);
-
- Error Err = LineTable.parse(LineExtractor, &StmtOffset, OrigDwarf,
- &Unit.getOrigUnit(), DWARFContext::dumpWarning);
- DWARFContext::dumpWarning(std::move(Err));
-
- // This vector is the output line table.
- std::vector<DWARFDebugLine::Row> NewRows;
- NewRows.reserve(LineTable.Rows.size());
-
- // Current sequence of rows being extracted, before being inserted
- // in NewRows.
- std::vector<DWARFDebugLine::Row> Seq;
- const auto &FunctionRanges = Unit.getFunctionRanges();
- auto InvalidRange = FunctionRanges.end(), CurrRange = InvalidRange;
-
- // FIXME: This logic is meant to generate exactly the same output as
- // Darwin's classic dsymutil. There is a nicer way to implement this
- // by simply putting all the relocated line info in NewRows and simply
- // sorting NewRows before passing it to emitLineTableForUnit. This
- // should be correct as sequences for a function should stay
- // together in the sorted output. There are a few corner cases that
- // look suspicious though, and that required to implement the logic
- // this way. Revisit that once initial validation is finished.
-
- // Iterate over the object file line info and extract the sequences
- // that correspond to linked functions.
- for (auto &Row : LineTable.Rows) {
- // Check whether we stepped out of the range. The range is
- // half-open, but consider accept the end address of the range if
- // it is marked as end_sequence in the input (because in that
- // case, the relocation offset is accurate and that entry won't
- // serve as the start of another function).
- if (CurrRange == InvalidRange || Row.Address.Address < CurrRange.start() ||
- Row.Address.Address > CurrRange.stop() ||
- (Row.Address.Address == CurrRange.stop() && !Row.EndSequence)) {
- // We just stepped out of a known range. Insert a end_sequence
- // corresponding to the end of the range.
- uint64_t StopAddress = CurrRange != InvalidRange
- ? CurrRange.stop() + CurrRange.value()
- : -1ULL;
- CurrRange = FunctionRanges.find(Row.Address.Address);
- bool CurrRangeValid =
- CurrRange != InvalidRange && CurrRange.start() <= Row.Address.Address;
- if (!CurrRangeValid) {
- CurrRange = InvalidRange;
- if (StopAddress != -1ULL) {
- // Try harder by looking in the DebugMapObject function
- // ranges map. There are corner cases where this finds a
- // valid entry. It's unclear if this is right or wrong, but
- // for now do as dsymutil.
- // FIXME: Understand exactly what cases this addresses and
- // potentially remove it along with the Ranges map.
- auto Range = Ranges.lower_bound(Row.Address.Address);
- if (Range != Ranges.begin() && Range != Ranges.end())
- --Range;
-
- if (Range != Ranges.end() && Range->first <= Row.Address.Address &&
- Range->second.HighPC >= Row.Address.Address) {
- StopAddress = Row.Address.Address + Range->second.Offset;
- }
- }
- }
- if (StopAddress != -1ULL && !Seq.empty()) {
- // Insert end sequence row with the computed end address, but
- // the same line as the previous one.
- auto NextLine = Seq.back();
- NextLine.Address.Address = StopAddress;
- NextLine.EndSequence = 1;
- NextLine.PrologueEnd = 0;
- NextLine.BasicBlock = 0;
- NextLine.EpilogueBegin = 0;
- Seq.push_back(NextLine);
- insertLineSequence(Seq, NewRows);
- }
-
- if (!CurrRangeValid)
- continue;
- }
-
- // Ignore empty sequences.
- if (Row.EndSequence && Seq.empty())
- continue;
-
- // Relocate row address and add it to the current sequence.
- Row.Address.Address += CurrRange.value();
- Seq.emplace_back(Row);
-
- if (Row.EndSequence)
- insertLineSequence(Seq, NewRows);
- }
-
- // Finished extracting, now emit the line tables.
- // FIXME: LLVM hard-codes its prologue values. We just copy the
- // prologue over and that works because we act as both producer and
- // consumer. It would be nicer to have a real configurable line
- // table emitter.
- if (LineTable.Prologue.getVersion() < 2 ||
- LineTable.Prologue.getVersion() > 5 ||
- LineTable.Prologue.DefaultIsStmt != DWARF2_LINE_DEFAULT_IS_STMT ||
- LineTable.Prologue.OpcodeBase > 13)
- reportWarning("line table parameters mismatch. Cannot emit.", DMO);
- else {
- uint32_t PrologueEnd = *StmtList + 10 + LineTable.Prologue.PrologueLength;
- // DWARF v5 has an extra 2 bytes of information before the header_length
- // field.
- if (LineTable.Prologue.getVersion() == 5)
- PrologueEnd += 2;
- StringRef LineData = OrigDwarf.getDWARFObj().getLineSection().Data;
- MCDwarfLineTableParams Params;
- Params.DWARF2LineOpcodeBase = LineTable.Prologue.OpcodeBase;
- Params.DWARF2LineBase = LineTable.Prologue.LineBase;
- Params.DWARF2LineRange = LineTable.Prologue.LineRange;
- Streamer->emitLineTableForUnit(Params,
- LineData.slice(*StmtList + 4, PrologueEnd),
- LineTable.Prologue.MinInstLength, NewRows,
- Unit.getOrigUnit().getAddressByteSize());
- }
-}
-
-void DwarfLinkerForBinary::emitAcceleratorEntriesForUnit(CompileUnit &Unit) {
- switch (Options.TheAccelTableKind) {
- case AccelTableKind::Apple:
- emitAppleAcceleratorEntriesForUnit(Unit);
- break;
- case AccelTableKind::Dwarf:
- emitDwarfAcceleratorEntriesForUnit(Unit);
- break;
- case AccelTableKind::Default:
- llvm_unreachable("The default must be updated to a concrete value.");
- break;
- }
-}
-
-void DwarfLinkerForBinary::emitAppleAcceleratorEntriesForUnit(
- CompileUnit &Unit) {
- // Add namespaces.
- for (const auto &Namespace : Unit.getNamespaces())
- AppleNamespaces.addName(Namespace.Name,
- Namespace.Die->getOffset() + Unit.getStartOffset());
-
- /// Add names.
- if (!Options.Minimize)
- Streamer->emitPubNamesForUnit(Unit);
- for (const auto &Pubname : Unit.getPubnames())
- AppleNames.addName(Pubname.Name,
- Pubname.Die->getOffset() + Unit.getStartOffset());
-
- /// Add types.
- if (!Options.Minimize)
- Streamer->emitPubTypesForUnit(Unit);
- for (const auto &Pubtype : Unit.getPubtypes())
- AppleTypes.addName(
- Pubtype.Name, Pubtype.Die->getOffset() + Unit.getStartOffset(),
- Pubtype.Die->getTag(),
- Pubtype.ObjcClassImplementation ? dwarf::DW_FLAG_type_implementation
- : 0,
- Pubtype.QualifiedNameHash);
-
- /// Add ObjC names.
- for (const auto &ObjC : Unit.getObjC())
- AppleObjc.addName(ObjC.Name, ObjC.Die->getOffset() + Unit.getStartOffset());
-}
-
-void DwarfLinkerForBinary::emitDwarfAcceleratorEntriesForUnit(
- CompileUnit &Unit) {
- for (const auto &Namespace : Unit.getNamespaces())
- DebugNames.addName(Namespace.Name, Namespace.Die->getOffset(),
- Namespace.Die->getTag(), Unit.getUniqueID());
- for (const auto &Pubname : Unit.getPubnames())
- DebugNames.addName(Pubname.Name, Pubname.Die->getOffset(),
- Pubname.Die->getTag(), Unit.getUniqueID());
- for (const auto &Pubtype : Unit.getPubtypes())
- DebugNames.addName(Pubtype.Name, Pubtype.Die->getOffset(),
- Pubtype.Die->getTag(), Unit.getUniqueID());
-}
-
-/// Read the frame info stored in the object, and emit the
-/// patched frame descriptions for the linked binary.
-///
-/// This is actually pretty easy as the data of the CIEs and FDEs can
-/// be considered as black boxes and moved as is. The only thing to do
-/// is to patch the addresses in the headers.
-void DwarfLinkerForBinary::patchFrameInfoForObject(const DebugMapObject &DMO,
- RangesTy &Ranges,
- DWARFContext &OrigDwarf,
- unsigned AddrSize) {
- StringRef FrameData = OrigDwarf.getDWARFObj().getFrameSection().Data;
- if (FrameData.empty())
- return;
-
- DataExtractor Data(FrameData, OrigDwarf.isLittleEndian(), 0);
- uint64_t InputOffset = 0;
-
- // Store the data of the CIEs defined in this object, keyed by their
- // offsets.
- DenseMap<uint64_t, StringRef> LocalCIES;
-
- while (Data.isValidOffset(InputOffset)) {
- uint64_t EntryOffset = InputOffset;
- uint32_t InitialLength = Data.getU32(&InputOffset);
- if (InitialLength == 0xFFFFFFFF)
- return reportWarning("Dwarf64 bits no supported", DMO);
-
- uint32_t CIEId = Data.getU32(&InputOffset);
- if (CIEId == 0xFFFFFFFF) {
- // This is a CIE, store it.
- StringRef CIEData = FrameData.substr(EntryOffset, InitialLength + 4);
- LocalCIES[EntryOffset] = CIEData;
- // The -4 is to account for the CIEId we just read.
- InputOffset += InitialLength - 4;
- continue;
- }
-
- uint32_t Loc = Data.getUnsigned(&InputOffset, AddrSize);
-
- // Some compilers seem to emit frame info that doesn't start at
- // the function entry point, thus we can't just lookup the address
- // in the debug map. Use the linker's range map to see if the FDE
- // describes something that we can relocate.
- auto Range = Ranges.upper_bound(Loc);
- if (Range != Ranges.begin())
- --Range;
- if (Range == Ranges.end() || Range->first > Loc ||
- Range->second.HighPC <= Loc) {
- // The +4 is to account for the size of the InitialLength field itself.
- InputOffset = EntryOffset + InitialLength + 4;
- continue;
- }
-
- // This is an FDE, and we have a mapping.
- // Have we already emitted a corresponding CIE?
- StringRef CIEData = LocalCIES[CIEId];
- if (CIEData.empty())
- return reportWarning("Inconsistent debug_frame content. Dropping.", DMO);
-
- // Look if we already emitted a CIE that corresponds to the
- // referenced one (the CIE data is the key of that lookup).
- auto IteratorInserted = EmittedCIEs.insert(
- std::make_pair(CIEData, Streamer->getFrameSectionSize()));
- // If there is no CIE yet for this ID, emit it.
- if (IteratorInserted.second ||
- // FIXME: dsymutil-classic only caches the last used CIE for
- // reuse. Mimic that behavior for now. Just removing that
- // second half of the condition and the LastCIEOffset variable
- // makes the code DTRT.
- LastCIEOffset != IteratorInserted.first->getValue()) {
- LastCIEOffset = Streamer->getFrameSectionSize();
- IteratorInserted.first->getValue() = LastCIEOffset;
- Streamer->emitCIE(CIEData);
- }
-
- // Emit the FDE with updated address and CIE pointer.
- // (4 + AddrSize) is the size of the CIEId + initial_location
- // fields that will get reconstructed by emitFDE().
- unsigned FDERemainingBytes = InitialLength - (4 + AddrSize);
- Streamer->emitFDE(IteratorInserted.first->getValue(), AddrSize,
- Loc + Range->second.Offset,
- FrameData.substr(InputOffset, FDERemainingBytes));
- InputOffset += FDERemainingBytes;
- }
-}
-
-void DwarfLinkerForBinary::DIECloner::copyAbbrev(
- const DWARFAbbreviationDeclaration &Abbrev, bool HasODR) {
- DIEAbbrev Copy(dwarf::Tag(Abbrev.getTag()),
- dwarf::Form(Abbrev.hasChildren()));
-
- for (const auto &Attr : Abbrev.attributes()) {
- uint16_t Form = Attr.Form;
- if (HasODR && isODRAttribute(Attr.Attr))
- Form = dwarf::DW_FORM_ref_addr;
- Copy.AddAttribute(dwarf::Attribute(Attr.Attr), dwarf::Form(Form));
- }
-
- Linker.assignAbbrev(Copy);
-}
-
-uint32_t DwarfLinkerForBinary::DIECloner::hashFullyQualifiedName(
- DWARFDie DIE, CompileUnit &U, const DebugMapObject &DMO,
- int ChildRecurseDepth) {
- const char *Name = nullptr;
- DWARFUnit *OrigUnit = &U.getOrigUnit();
- CompileUnit *CU = &U;
- Optional<DWARFFormValue> Ref;
-
- while (1) {
- if (const char *CurrentName = DIE.getName(DINameKind::ShortName))
- Name = CurrentName;
-
- if (!(Ref = DIE.find(dwarf::DW_AT_specification)) &&
- !(Ref = DIE.find(dwarf::DW_AT_abstract_origin)))
- break;
-
- if (!Ref->isFormClass(DWARFFormValue::FC_Reference))
- break;
-
- CompileUnit *RefCU;
- if (auto RefDIE =
- resolveDIEReference(Linker, DMO, CompileUnits, *Ref, DIE, RefCU)) {
- CU = RefCU;
- OrigUnit = &RefCU->getOrigUnit();
- DIE = RefDIE;
- }
- }
-
- unsigned Idx = OrigUnit->getDIEIndex(DIE);
- if (!Name && DIE.getTag() == dwarf::DW_TAG_namespace)
- Name = "(anonymous namespace)";
-
- if (CU->getInfo(Idx).ParentIdx == 0 ||
- // FIXME: dsymutil-classic compatibility. Ignore modules.
- CU->getOrigUnit().getDIEAtIndex(CU->getInfo(Idx).ParentIdx).getTag() ==
- dwarf::DW_TAG_module)
- return djbHash(Name ? Name : "", djbHash(ChildRecurseDepth ? "" : "::"));
-
- DWARFDie Die = OrigUnit->getDIEAtIndex(CU->getInfo(Idx).ParentIdx);
- return djbHash(
- (Name ? Name : ""),
- djbHash((Name ? "::" : ""),
- hashFullyQualifiedName(Die, *CU, DMO, ++ChildRecurseDepth)));
-}
-
-static uint64_t getDwoId(const DWARFDie &CUDie, const DWARFUnit &Unit) {
- auto DwoId = dwarf::toUnsigned(
- CUDie.find({dwarf::DW_AT_dwo_id, dwarf::DW_AT_GNU_dwo_id}));
- if (DwoId)
- return *DwoId;
- return 0;
-}
-
-bool DwarfLinkerForBinary::registerModuleReference(
- DWARFDie CUDie, const DWARFUnit &Unit, DebugMap &ModuleMap,
- const DebugMapObject &DMO, RangesTy &Ranges, OffsetsStringPool &StringPool,
- UniquingStringPool &UniquingStringPool, DeclContextTree &ODRContexts,
- uint64_t ModulesEndOffset, unsigned &UnitID, bool IsLittleEndian,
- unsigned Indent, bool Quiet) {
- std::string PCMfile = dwarf::toString(
- CUDie.find({dwarf::DW_AT_dwo_name, dwarf::DW_AT_GNU_dwo_name}), "");
- if (PCMfile.empty())
- return false;
-
- // Clang module DWARF skeleton CUs abuse this for the path to the module.
- uint64_t DwoId = getDwoId(CUDie, Unit);
-
- std::string Name = dwarf::toString(CUDie.find(dwarf::DW_AT_name), "");
- if (Name.empty()) {
- if (!Quiet)
- reportWarning("Anonymous module skeleton CU for " + PCMfile, DMO);
- return true;
- }
-
- if (!Quiet && Options.Verbose) {
- outs().indent(Indent);
- outs() << "Found clang module reference " << PCMfile;
- }
-
- auto Cached = ClangModules.find(PCMfile);
- if (Cached != ClangModules.end()) {
- // FIXME: Until PR27449 (https://llvm.org/bugs/show_bug.cgi?id=27449) is
- // fixed in clang, only warn about DWO_id mismatches in verbose mode.
- // ASTFileSignatures will change randomly when a module is rebuilt.
- if (!Quiet && Options.Verbose && (Cached->second != DwoId))
- reportWarning(Twine("hash mismatch: this object file was built against a "
- "
diff erent version of the module ") +
- PCMfile,
- DMO);
- if (!Quiet && Options.Verbose)
- outs() << " [cached].\n";
- return true;
- }
- if (!Quiet && Options.Verbose)
- outs() << " ...\n";
-
- // Cyclic dependencies are disallowed by Clang, but we still
- // shouldn't run into an infinite loop, so mark it as processed now.
- ClangModules.insert({PCMfile, DwoId});
-
- if (Error E = loadClangModule(CUDie, PCMfile, Name, DwoId, ModuleMap, DMO,
- Ranges, StringPool, UniquingStringPool,
- ODRContexts, ModulesEndOffset, UnitID,
- IsLittleEndian, Indent + 2, Quiet)) {
- consumeError(std::move(E));
- return false;
- }
- return true;
-}
-
-ErrorOr<const object::ObjectFile &>
-DwarfLinkerForBinary::loadObject(const DebugMapObject &Obj,
- const DebugMap &Map) {
- auto ObjectEntry =
- BinHolder.getObjectEntry(Obj.getObjectFilename(), Obj.getTimestamp());
- if (!ObjectEntry) {
- auto Err = ObjectEntry.takeError();
- reportWarning(
- Twine(Obj.getObjectFilename()) + ": " + toString(std::move(Err)), Obj);
- return errorToErrorCode(std::move(Err));
- }
-
- auto Object = ObjectEntry->getObject(Map.getTriple());
- if (!Object) {
- auto Err = Object.takeError();
- reportWarning(
- Twine(Obj.getObjectFilename()) + ": " + toString(std::move(Err)), Obj);
- return errorToErrorCode(std::move(Err));
- }
-
- return *Object;
-}
-
-Error DwarfLinkerForBinary::loadClangModule(
- DWARFDie CUDie, StringRef Filename, StringRef ModuleName, uint64_t DwoId,
- DebugMap &ModuleMap, const DebugMapObject &DMO, RangesTy &Ranges,
- OffsetsStringPool &StringPool, UniquingStringPool &UniquingStringPool,
- DeclContextTree &ODRContexts, uint64_t ModulesEndOffset, unsigned &UnitID,
- bool IsLittleEndian, unsigned Indent, bool Quiet) {
- /// Using a SmallString<0> because loadClangModule() is recursive.
- SmallString<0> Path(Options.PrependPath);
- if (sys::path::is_relative(Filename))
- resolveRelativeObjectPath(Path, CUDie);
- sys::path::append(Path, Filename);
- // Don't use the cached binary holder because we have no thread-safety
- // guarantee and the lifetime is limited.
- auto &Obj = ModuleMap.addDebugMapObject(
- Path, sys::TimePoint<std::chrono::seconds>(), MachO::N_OSO);
- auto ErrOrObj = loadObject(Obj, ModuleMap);
- if (!ErrOrObj) {
- // Try and emit more helpful warnings by applying some heuristics.
- StringRef ObjFile = DMO.getObjectFilename();
- bool isClangModule = sys::path::extension(Filename).equals(".pcm");
- bool isArchive = ObjFile.endswith(")");
- if (isClangModule) {
- StringRef ModuleCacheDir = sys::path::parent_path(Path);
- if (sys::fs::exists(ModuleCacheDir)) {
- // If the module's parent directory exists, we assume that the module
- // cache has expired and was pruned by clang. A more adventurous
- // dsymutil would invoke clang to rebuild the module now.
- if (!ModuleCacheHintDisplayed) {
- WithColor::note() << "The clang module cache may have expired since "
- "this object file was built. Rebuilding the "
- "object file will rebuild the module cache.\n";
- ModuleCacheHintDisplayed = true;
- }
- } else if (isArchive) {
- // If the module cache directory doesn't exist at all and the object
- // file is inside a static library, we assume that the static library
- // was built on a
diff erent machine. We don't want to discourage module
- // debugging for convenience libraries within a project though.
- if (!ArchiveHintDisplayed) {
- WithColor::note()
- << "Linking a static library that was built with "
- "-gmodules, but the module cache was not found. "
- "Redistributable static libraries should never be "
- "built with module debugging enabled. The debug "
- "experience will be degraded due to incomplete "
- "debug information.\n";
- ArchiveHintDisplayed = true;
- }
- }
- }
- return Error::success();
- }
-
- std::unique_ptr<CompileUnit> Unit;
-
- // Setup access to the debug info.
- auto DwarfContext = DWARFContext::create(*ErrOrObj);
- RelocationManager RelocMgr(*this, *ErrOrObj, DMO);
-
- for (const auto &CU : DwarfContext->compile_units()) {
- updateDwarfVersion(CU->getVersion());
- // Recursively get all modules imported by this one.
- auto CUDie = CU->getUnitDIE(false);
- if (!CUDie)
- continue;
- if (!registerModuleReference(CUDie, *CU, ModuleMap, DMO, Ranges, StringPool,
- UniquingStringPool, ODRContexts,
- ModulesEndOffset, UnitID, IsLittleEndian,
- Indent, Quiet)) {
- if (Unit) {
- std::string Err =
- (Filename +
- ": Clang modules are expected to have exactly 1 compile unit.\n")
- .str();
- error(Err);
- return make_error<StringError>(Err, inconvertibleErrorCode());
- }
- // FIXME: Until PR27449 (https://llvm.org/bugs/show_bug.cgi?id=27449) is
- // fixed in clang, only warn about DWO_id mismatches in verbose mode.
- // ASTFileSignatures will change randomly when a module is rebuilt.
- uint64_t PCMDwoId = getDwoId(CUDie, *CU);
- if (PCMDwoId != DwoId) {
- if (!Quiet && Options.Verbose)
- reportWarning(
- Twine("hash mismatch: this object file was built against a "
- "
diff erent version of the module ") +
- Filename,
- DMO);
- // Update the cache entry with the DwoId of the module loaded from disk.
- ClangModules[Filename] = PCMDwoId;
- }
-
- // Add this module.
- Unit = std::make_unique<CompileUnit>(*CU, UnitID++, !Options.NoODR,
- ModuleName);
- Unit->setHasInterestingContent();
- analyzeContextInfo(CUDie, 0, *Unit, &ODRContexts.getRoot(),
- UniquingStringPool, ODRContexts, ModulesEndOffset,
- ParseableSwiftInterfaces,
- [&](const Twine &Warning, const DWARFDie &DIE) {
- reportWarning(Warning, DMO, &DIE);
- });
- // Keep everything.
- Unit->markEverythingAsKept();
- }
- }
- if (!Unit->getOrigUnit().getUnitDIE().hasChildren())
- return Error::success();
- if (!Quiet && Options.Verbose) {
- outs().indent(Indent);
- outs() << "cloning .debug_info from " << Filename << "\n";
- }
-
- UnitListTy CompileUnits;
- CompileUnits.push_back(std::move(Unit));
- DIECloner(*this, RelocMgr, DIEAlloc, CompileUnits, Options)
- .cloneAllCompileUnits(*DwarfContext, DMO, Ranges, StringPool,
- IsLittleEndian);
- return Error::success();
-}
-
-void DwarfLinkerForBinary::DIECloner::cloneAllCompileUnits(
- DWARFContext &DwarfContext, const DebugMapObject &DMO, RangesTy &Ranges,
- OffsetsStringPool &StringPool, bool IsLittleEndian) {
- if (!Linker.Streamer)
- return;
-
- uint64_t OutputDebugInfoSize = Linker.Streamer->getDebugInfoSectionSize();
- for (auto &CurrentUnit : CompileUnits) {
- auto InputDIE = CurrentUnit->getOrigUnit().getUnitDIE();
- CurrentUnit->setStartOffset(OutputDebugInfoSize);
- if (!InputDIE) {
- OutputDebugInfoSize = CurrentUnit->computeNextUnitOffset();
- continue;
- }
- if (CurrentUnit->getInfo(0).Keep) {
- // Clone the InputDIE into your Unit DIE in our compile unit since it
- // already has a DIE inside of it.
- CurrentUnit->createOutputDIE();
- cloneDIE(InputDIE, DMO, *CurrentUnit, StringPool, 0 /* PC offset */,
- 11 /* Unit Header size */, 0, IsLittleEndian,
- CurrentUnit->getOutputUnitDIE());
- }
-
- OutputDebugInfoSize = CurrentUnit->computeNextUnitOffset();
-
- if (Linker.Options.NoOutput)
- continue;
-
- // FIXME: for compatibility with the classic dsymutil, we emit
- // an empty line table for the unit, even if the unit doesn't
- // actually exist in the DIE tree.
- if (LLVM_LIKELY(!Linker.Options.Update) || Linker.Options.Translator)
- Linker.patchLineTableForUnit(*CurrentUnit, DwarfContext, Ranges, DMO);
-
- Linker.emitAcceleratorEntriesForUnit(*CurrentUnit);
-
- if (LLVM_UNLIKELY(Linker.Options.Update))
- continue;
-
- Linker.patchRangesForUnit(*CurrentUnit, DwarfContext, DMO);
- auto ProcessExpr = [&](StringRef Bytes, SmallVectorImpl<uint8_t> &Buffer) {
- DWARFUnit &OrigUnit = CurrentUnit->getOrigUnit();
- DataExtractor Data(Bytes, IsLittleEndian, OrigUnit.getAddressByteSize());
- cloneExpression(Data,
- DWARFExpression(Data, OrigUnit.getVersion(),
- OrigUnit.getAddressByteSize()),
- DMO, *CurrentUnit, Buffer);
- };
- Linker.Streamer->emitLocationsForUnit(*CurrentUnit, DwarfContext,
- ProcessExpr);
- }
-
- if (Linker.Options.NoOutput)
- return;
-
- // Emit all the compile unit's debug information.
- for (auto &CurrentUnit : CompileUnits) {
- if (LLVM_LIKELY(!Linker.Options.Update))
- Linker.generateUnitRanges(*CurrentUnit);
-
- CurrentUnit->fixupForwardReferences();
-
- if (!CurrentUnit->getOutputUnitDIE())
- continue;
-
- assert(Linker.Streamer->getDebugInfoSectionSize() ==
- CurrentUnit->getStartOffset());
- Linker.Streamer->emitCompileUnitHeader(*CurrentUnit);
- Linker.Streamer->emitDIE(*CurrentUnit->getOutputUnitDIE());
- assert(Linker.Streamer->getDebugInfoSectionSize() ==
- CurrentUnit->computeNextUnitOffset());
- }
-}
-
-void DwarfLinkerForBinary::updateAccelKind(DWARFContext &Dwarf) {
- if (Options.TheAccelTableKind != AccelTableKind::Default)
- return;
-
- auto &DwarfObj = Dwarf.getDWARFObj();
-
- if (!AtLeastOneDwarfAccelTable &&
- (!DwarfObj.getAppleNamesSection().Data.empty() ||
- !DwarfObj.getAppleTypesSection().Data.empty() ||
- !DwarfObj.getAppleNamespacesSection().Data.empty() ||
- !DwarfObj.getAppleObjCSection().Data.empty())) {
- AtLeastOneAppleAccelTable = true;
- }
-
- if (!AtLeastOneDwarfAccelTable && !DwarfObj.getNamesSection().Data.empty()) {
- AtLeastOneDwarfAccelTable = true;
- }
-}
-
-bool DwarfLinkerForBinary::emitPaperTrailWarnings(
- const DebugMapObject &DMO, const DebugMap &Map,
- OffsetsStringPool &StringPool) {
- if (DMO.getWarnings().empty() || !DMO.empty())
- return false;
-
- Streamer->switchToDebugInfoSection(/* Version */ 2);
- DIE *CUDie = DIE::get(DIEAlloc, dwarf::DW_TAG_compile_unit);
- CUDie->setOffset(11);
- StringRef Producer = StringPool.internString("dsymutil");
- StringRef File = StringPool.internString(DMO.getObjectFilename());
- CUDie->addValue(DIEAlloc, dwarf::DW_AT_producer, dwarf::DW_FORM_strp,
- DIEInteger(StringPool.getStringOffset(Producer)));
- DIEBlock *String = new (DIEAlloc) DIEBlock();
- DIEBlocks.push_back(String);
- for (auto &C : File)
- String->addValue(DIEAlloc, dwarf::Attribute(0), dwarf::DW_FORM_data1,
- DIEInteger(C));
- String->addValue(DIEAlloc, dwarf::Attribute(0), dwarf::DW_FORM_data1,
- DIEInteger(0));
-
- CUDie->addValue(DIEAlloc, dwarf::DW_AT_name, dwarf::DW_FORM_string, String);
- for (const auto &Warning : DMO.getWarnings()) {
- DIE &ConstDie = CUDie->addChild(DIE::get(DIEAlloc, dwarf::DW_TAG_constant));
- ConstDie.addValue(
- DIEAlloc, dwarf::DW_AT_name, dwarf::DW_FORM_strp,
- DIEInteger(StringPool.getStringOffset("dsymutil_warning")));
- ConstDie.addValue(DIEAlloc, dwarf::DW_AT_artificial, dwarf::DW_FORM_flag,
- DIEInteger(1));
- ConstDie.addValue(DIEAlloc, dwarf::DW_AT_const_value, dwarf::DW_FORM_strp,
- DIEInteger(StringPool.getStringOffset(Warning)));
- }
- unsigned Size = 4 /* FORM_strp */ + File.size() + 1 +
- DMO.getWarnings().size() * (4 + 1 + 4) +
- 1 /* End of children */;
- DIEAbbrev Abbrev = CUDie->generateAbbrev();
- assignAbbrev(Abbrev);
- CUDie->setAbbrevNumber(Abbrev.getNumber());
- Size += getULEB128Size(Abbrev.getNumber());
- // Abbreviation ordering needed for classic compatibility.
- for (auto &Child : CUDie->children()) {
- Abbrev = Child.generateAbbrev();
- assignAbbrev(Abbrev);
- Child.setAbbrevNumber(Abbrev.getNumber());
- Size += getULEB128Size(Abbrev.getNumber());
- }
- CUDie->setSize(Size);
- Streamer->emitPaperTrailWarningsDie(Map.getTriple(), *CUDie);
-
- return true;
-}
-
-static Error copySwiftInterfaces(
- const std::map<std::string, std::string> &ParseableSwiftInterfaces,
- StringRef Architecture, const LinkOptions &Options) {
- std::error_code EC;
- SmallString<128> InputPath;
- SmallString<128> Path;
- sys::path::append(Path, *Options.ResourceDir, "Swift", Architecture);
- if ((EC = sys::fs::create_directories(Path.str(), true,
- sys::fs::perms::all_all)))
- return make_error<StringError>(
- "cannot create directory: " + toString(errorCodeToError(EC)), EC);
- unsigned BaseLength = Path.size();
-
- for (auto &I : ParseableSwiftInterfaces) {
- StringRef ModuleName = I.first;
- StringRef InterfaceFile = I.second;
- if (!Options.PrependPath.empty()) {
- InputPath.clear();
- sys::path::append(InputPath, Options.PrependPath, InterfaceFile);
- InterfaceFile = InputPath;
- }
- sys::path::append(Path, ModuleName);
- Path.append(".swiftinterface");
- if (Options.Verbose)
- outs() << "copy parseable Swift interface " << InterfaceFile << " -> "
- << Path.str() << '\n';
-
- // copy_file attempts an APFS clone first, so this should be cheap.
- if ((EC = sys::fs::copy_file(InterfaceFile, Path.str())))
- warn(Twine("cannot copy parseable Swift interface ") + InterfaceFile +
- ": " + toString(errorCodeToError(EC)));
- Path.resize(BaseLength);
- }
- return Error::success();
-}
-
-static Error emitRemarks(const LinkOptions &Options, StringRef BinaryPath,
- StringRef ArchName, const remarks::RemarkLinker &RL) {
- // Make sure we don't create the directories and the file if there is nothing
- // to serialize.
- if (RL.empty())
- return Error::success();
-
- SmallString<128> InputPath;
- SmallString<128> Path;
- // Create the "Remarks" directory in the "Resources" directory.
- sys::path::append(Path, *Options.ResourceDir, "Remarks");
- if (std::error_code EC = sys::fs::create_directories(Path.str(), true,
- sys::fs::perms::all_all))
- return errorCodeToError(EC);
-
- // Append the file name.
- // For fat binaries, also append a dash and the architecture name.
- sys::path::append(Path, sys::path::filename(BinaryPath));
- if (Options.NumDebugMaps > 1) {
- // More than one debug map means we have a fat binary.
- Path += '-';
- Path += ArchName;
- }
-
- std::error_code EC;
- raw_fd_ostream OS(Options.NoOutput ? "-" : Path.str(), EC, sys::fs::OF_None);
- if (EC)
- return errorCodeToError(EC);
-
- if (Error E = RL.serialize(OS, Options.RemarksFormat))
- return E;
-
- return Error::success();
-}
-
-bool DwarfLinkerForBinary::link(const DebugMap &Map) {
- if (!createStreamer(Map.getTriple(), OutFile))
- return false;
-
- // Size of the DIEs (and headers) generated for the linked output.
- // A unique ID that identifies each compile unit.
- unsigned UnitID = 0;
- DebugMap ModuleMap(Map.getTriple(), Map.getBinaryPath());
-
- // First populate the data structure we need for each iteration of the
- // parallel loop.
- unsigned NumObjects = Map.getNumberOfObjects();
- std::vector<LinkContext> ObjectContexts;
- ObjectContexts.reserve(NumObjects);
- for (const auto &Obj : Map.objects()) {
- ObjectContexts.emplace_back(Map, *this, *Obj.get());
- LinkContext &LC = ObjectContexts.back();
- if (LC.ObjectFile)
- updateAccelKind(*LC.DwarfContext);
- }
-
- // This Dwarf string pool which is only used for uniquing. This one should
- // never be used for offsets as its not thread-safe or predictable.
- UniquingStringPool UniquingStringPool(nullptr, true);
-
- // This Dwarf string pool which is used for emission. It must be used
- // serially as the order of calling getStringOffset matters for
- // reproducibility.
- OffsetsStringPool OffsetsStringPool(Options.Translator, true);
-
- // ODR Contexts for the link.
- DeclContextTree ODRContexts;
-
- // If we haven't decided on an accelerator table kind yet, we base ourselves
- // on the DWARF we have seen so far. At this point we haven't pulled in debug
- // information from modules yet, so it is technically possible that they
- // would affect the decision. However, as they're built with the same
- // compiler and flags, it is safe to assume that they will follow the
- // decision made here.
- if (Options.TheAccelTableKind == AccelTableKind::Default) {
- if (AtLeastOneDwarfAccelTable && !AtLeastOneAppleAccelTable)
- Options.TheAccelTableKind = AccelTableKind::Dwarf;
- else
- Options.TheAccelTableKind = AccelTableKind::Apple;
- }
-
- for (LinkContext &LinkContext : ObjectContexts) {
- if (Options.Verbose)
- outs() << "DEBUG MAP OBJECT: " << LinkContext.DMO.getObjectFilename()
- << "\n";
-
- // N_AST objects (swiftmodule files) should get dumped directly into the
- // appropriate DWARF section.
- if (LinkContext.DMO.getType() == MachO::N_AST) {
- StringRef File = LinkContext.DMO.getObjectFilename();
- auto ErrorOrMem = MemoryBuffer::getFile(File);
- if (!ErrorOrMem) {
- warn("Could not open '" + File + "'\n");
- continue;
- }
- sys::fs::file_status Stat;
- if (auto Err = sys::fs::status(File, Stat)) {
- warn(Err.message());
- continue;
- }
- if (!Options.NoTimestamp) {
- // The modification can have sub-second precision so we need to cast
- // away the extra precision that's not present in the debug map.
- auto ModificationTime =
- std::chrono::time_point_cast<std::chrono::seconds>(
- Stat.getLastModificationTime());
- if (ModificationTime != LinkContext.DMO.getTimestamp()) {
- // Not using the helper here as we can easily stream TimePoint<>.
- WithColor::warning()
- << "Timestamp mismatch for " << File << ": "
- << Stat.getLastModificationTime() << " and "
- << sys::TimePoint<>(LinkContext.DMO.getTimestamp()) << "\n";
- continue;
- }
- }
-
- // Copy the module into the .swift_ast section.
- if (!Options.NoOutput)
- Streamer->emitSwiftAST((*ErrorOrMem)->getBuffer());
- continue;
- }
-
- if (emitPaperTrailWarnings(LinkContext.DMO, Map, OffsetsStringPool))
- continue;
-
- if (!LinkContext.ObjectFile)
- continue;
-
- // Look for relocations that correspond to debug map entries.
-
- if (LLVM_LIKELY(!Options.Update) &&
- !LinkContext.RelocMgr->hasValidRelocs()) {
- if (Options.Verbose)
- outs() << "No valid relocations found. Skipping.\n";
-
- // Clear this ObjFile entry as a signal to other loops that we should not
- // process this iteration.
- LinkContext.ObjectFile = nullptr;
- continue;
- }
-
- // Setup access to the debug info.
- if (!LinkContext.DwarfContext)
- continue;
-
- startDebugObject(LinkContext);
-
- // In a first phase, just read in the debug info and load all clang modules.
- LinkContext.CompileUnits.reserve(
- LinkContext.DwarfContext->getNumCompileUnits());
-
- for (const auto &CU : LinkContext.DwarfContext->compile_units()) {
- updateDwarfVersion(CU->getVersion());
- auto CUDie = CU->getUnitDIE(false);
- if (Options.Verbose) {
- outs() << "Input compilation unit:";
- DIDumpOptions DumpOpts;
- DumpOpts.ChildRecurseDepth = 0;
- DumpOpts.Verbose = Options.Verbose;
- CUDie.dump(outs(), 0, DumpOpts);
- }
- if (CUDie && !LLVM_UNLIKELY(Options.Update))
- registerModuleReference(CUDie, *CU, ModuleMap, LinkContext.DMO,
- LinkContext.Ranges, OffsetsStringPool,
- UniquingStringPool, ODRContexts, 0, UnitID,
- LinkContext.DwarfContext->isLittleEndian());
- }
- }
-
- // If we haven't seen any CUs, pick an arbitrary valid Dwarf version anyway.
- if (MaxDwarfVersion == 0)
- MaxDwarfVersion = 3;
-
- // At this point we know how much data we have emitted. We use this value to
- // compare canonical DIE offsets in analyzeContextInfo to see if a definition
- // is already emitted, without being affected by canonical die offsets set
- // later. This prevents undeterminism when analyze and clone execute
- // concurrently, as clone set the canonical DIE offset and analyze reads it.
- const uint64_t ModulesEndOffset =
- Options.NoOutput ? 0 : Streamer->getDebugInfoSectionSize();
-
- // These variables manage the list of processed object files.
- // The mutex and condition variable are to ensure that this is thread safe.
- std::mutex ProcessedFilesMutex;
- std::condition_variable ProcessedFilesConditionVariable;
- BitVector ProcessedFiles(NumObjects, false);
-
- // Analyzing the context info is particularly expensive so it is executed in
- // parallel with emitting the previous compile unit.
- auto AnalyzeLambda = [&](size_t i) {
- auto &LinkContext = ObjectContexts[i];
-
- if (!LinkContext.ObjectFile || !LinkContext.DwarfContext)
- return;
-
- for (const auto &CU : LinkContext.DwarfContext->compile_units()) {
- updateDwarfVersion(CU->getVersion());
- // The !registerModuleReference() condition effectively skips
- // over fully resolved skeleton units. This second pass of
- // registerModuleReferences doesn't do any new work, but it
- // will collect top-level errors, which are suppressed. Module
- // warnings were already displayed in the first iteration.
- bool Quiet = true;
- auto CUDie = CU->getUnitDIE(false);
- if (!CUDie || LLVM_UNLIKELY(Options.Update) ||
- !registerModuleReference(CUDie, *CU, ModuleMap, LinkContext.DMO,
- LinkContext.Ranges, OffsetsStringPool,
- UniquingStringPool, ODRContexts,
- ModulesEndOffset, UnitID, Quiet)) {
- LinkContext.CompileUnits.push_back(std::make_unique<CompileUnit>(
- *CU, UnitID++, !Options.NoODR && !Options.Update, ""));
- }
- }
-
- // Now build the DIE parent links that we will use during the next phase.
- for (auto &CurrentUnit : LinkContext.CompileUnits) {
- auto CUDie = CurrentUnit->getOrigUnit().getUnitDIE();
- if (!CUDie)
- continue;
- analyzeContextInfo(CurrentUnit->getOrigUnit().getUnitDIE(), 0,
- *CurrentUnit, &ODRContexts.getRoot(),
- UniquingStringPool, ODRContexts, ModulesEndOffset,
- ParseableSwiftInterfaces,
- [&](const Twine &Warning, const DWARFDie &DIE) {
- reportWarning(Warning, LinkContext.DMO, &DIE);
- });
- }
- };
-
- // And then the remaining work in serial again.
- // Note, although this loop runs in serial, it can run in parallel with
- // the analyzeContextInfo loop so long as we process files with indices >=
- // than those processed by analyzeContextInfo.
- auto CloneLambda = [&](size_t i) {
- auto &LinkContext = ObjectContexts[i];
- if (!LinkContext.ObjectFile)
- return;
-
- // Then mark all the DIEs that need to be present in the linked output
- // and collect some information about them.
- // Note that this loop can not be merged with the previous one because
- // cross-cu references require the ParentIdx to be setup for every CU in
- // the object file before calling this.
- if (LLVM_UNLIKELY(Options.Update)) {
- for (auto &CurrentUnit : LinkContext.CompileUnits)
- CurrentUnit->markEverythingAsKept();
- Streamer->copyInvariantDebugSection(*LinkContext.ObjectFile);
- } else {
- for (auto &CurrentUnit : LinkContext.CompileUnits)
- lookForDIEsToKeep(*LinkContext.RelocMgr, LinkContext.Ranges,
- LinkContext.CompileUnits,
- CurrentUnit->getOrigUnit().getUnitDIE(),
- LinkContext.DMO, *CurrentUnit, 0);
- }
-
- // The calls to applyValidRelocs inside cloneDIE will walk the reloc
- // array again (in the same way findValidRelocsInDebugInfo() did). We
- // need to reset the NextValidReloc index to the beginning.
- if (LinkContext.RelocMgr->hasValidRelocs() || LLVM_UNLIKELY(Options.Update))
- DIECloner(*this, *LinkContext.RelocMgr, DIEAlloc,
- LinkContext.CompileUnits, Options)
- .cloneAllCompileUnits(*LinkContext.DwarfContext, LinkContext.DMO,
- LinkContext.Ranges, OffsetsStringPool,
- LinkContext.DwarfContext->isLittleEndian());
- if (!Options.NoOutput && !LinkContext.CompileUnits.empty() &&
- LLVM_LIKELY(!Options.Update))
- patchFrameInfoForObject(
- LinkContext.DMO, LinkContext.Ranges, *LinkContext.DwarfContext,
- LinkContext.CompileUnits[0]->getOrigUnit().getAddressByteSize());
-
- // Clean-up before starting working on the next object.
- endDebugObject(LinkContext);
- };
-
- auto EmitLambda = [&]() {
- // Emit everything that's global.
- if (!Options.NoOutput) {
- Streamer->emitAbbrevs(Abbreviations, MaxDwarfVersion);
- Streamer->emitStrings(OffsetsStringPool);
- switch (Options.TheAccelTableKind) {
- case AccelTableKind::Apple:
- Streamer->emitAppleNames(AppleNames);
- Streamer->emitAppleNamespaces(AppleNamespaces);
- Streamer->emitAppleTypes(AppleTypes);
- Streamer->emitAppleObjc(AppleObjc);
- break;
- case AccelTableKind::Dwarf:
- Streamer->emitDebugNames(DebugNames);
- break;
- case AccelTableKind::Default:
- llvm_unreachable("Default should have already been resolved.");
- break;
- }
- }
- };
-
- remarks::RemarkLinker RL;
- if (!Options.RemarksPrependPath.empty())
- RL.setExternalFilePrependPath(Options.RemarksPrependPath);
- auto RemarkLinkLambda = [&](size_t i) {
- // Link remarks from one object file.
- auto &LinkContext = ObjectContexts[i];
- if (const object::ObjectFile *Obj = LinkContext.ObjectFile) {
- Error E = RL.link(*Obj);
- if (Error NewE = handleErrors(
- std::move(E), [&](std::unique_ptr<FileError> EC) -> Error {
- return remarksErrorHandler(LinkContext.DMO, *this,
- std::move(EC));
- }))
- return NewE;
- }
- return Error(Error::success());
- };
-
- auto AnalyzeAll = [&]() {
- for (unsigned i = 0, e = NumObjects; i != e; ++i) {
- AnalyzeLambda(i);
-
- std::unique_lock<std::mutex> LockGuard(ProcessedFilesMutex);
- ProcessedFiles.set(i);
- ProcessedFilesConditionVariable.notify_one();
- }
- };
-
- auto CloneAll = [&]() {
- for (unsigned i = 0, e = NumObjects; i != e; ++i) {
- {
- std::unique_lock<std::mutex> LockGuard(ProcessedFilesMutex);
- if (!ProcessedFiles[i]) {
- ProcessedFilesConditionVariable.wait(
- LockGuard, [&]() { return ProcessedFiles[i]; });
- }
- }
-
- CloneLambda(i);
- }
- EmitLambda();
- };
-
- auto EmitRemarksLambda = [&]() {
- StringRef ArchName = Map.getTriple().getArchName();
- return emitRemarks(Options, Map.getBinaryPath(), ArchName, RL);
- };
-
- // Instead of making error handling a lot more complicated using futures,
- // write to one llvm::Error instance if something went wrong.
- // We're assuming RemarkLinkAllError is alive longer than the thread
- // executing RemarkLinkAll.
- auto RemarkLinkAll = [&](Error &RemarkLinkAllError) {
- // Allow assigning to the error only within the lambda.
- ErrorAsOutParameter EAO(&RemarkLinkAllError);
- for (unsigned i = 0, e = NumObjects; i != e; ++i)
- if ((RemarkLinkAllError = RemarkLinkLambda(i)))
- return;
-
- if ((RemarkLinkAllError = EmitRemarksLambda()))
- return;
- };
-
- // To limit memory usage in the single threaded case, analyze and clone are
- // run sequentially so the LinkContext is freed after processing each object
- // in endDebugObject.
- if (Options.Threads == 1) {
- for (unsigned i = 0, e = NumObjects; i != e; ++i) {
- AnalyzeLambda(i);
- CloneLambda(i);
-
- if (Error E = RemarkLinkLambda(i))
- return error(toString(std::move(E)));
- }
- EmitLambda();
-
- if (Error E = EmitRemarksLambda())
- return error(toString(std::move(E)));
-
- } else {
- // This should not be constructed on the single-threaded path to avoid fatal
- // errors from unchecked llvm::Error objects.
- Error RemarkLinkAllError = Error::success();
-
- ThreadPool pool(3);
- pool.async(AnalyzeAll);
- pool.async(CloneAll);
- pool.async(RemarkLinkAll, std::ref(RemarkLinkAllError));
- pool.wait();
-
- // Report errors from RemarkLinkAll, if any.
- if (Error E = std::move(RemarkLinkAllError))
- return error(toString(std::move(E)));
- }
-
- if (Options.NoOutput)
- return true;
-
- if (Options.ResourceDir && !ParseableSwiftInterfaces.empty()) {
- StringRef ArchName = Triple::getArchTypeName(Map.getTriple().getArch());
- if (auto E =
- copySwiftInterfaces(ParseableSwiftInterfaces, ArchName, Options))
- return error(toString(std::move(E)));
- }
-
- return Streamer->finish(Map, Options.Translator);
-} // namespace dsymutil
-
bool linkDwarf(raw_fd_ostream &OutFile, BinaryHolder &BinHolder,
const DebugMap &DM, LinkOptions Options) {
DwarfLinkerForBinary Linker(OutFile, BinHolder, std::move(Options));
diff --git a/llvm/tools/dsymutil/DwarfLinkerForBinary.h b/llvm/tools/dsymutil/DwarfLinkerForBinary.h
index 018729a7c423..f9f7c2abcb00 100644
--- a/llvm/tools/dsymutil/DwarfLinkerForBinary.h
+++ b/llvm/tools/dsymutil/DwarfLinkerForBinary.h
@@ -17,26 +17,20 @@
#include "llvm/DWARFLinker/DWARFLinkerCompileUnit.h"
#include "llvm/DWARFLinker/DWARFLinkerDeclContext.h"
#include "llvm/DebugInfo/DWARF/DWARFContext.h"
+#include "llvm/Remarks/RemarkFormat.h"
+#include "llvm/Remarks/RemarkLinker.h"
namespace llvm {
namespace dsymutil {
-using UnitListTy = std::vector<std::unique_ptr<CompileUnit>>;
-
-/// The core of the Dwarf linking logic.
+/// The core of the Dsymutil Dwarf linking logic.
///
/// The link of the dwarf information from the object files will be
-/// driven by the selection of 'root DIEs', which are DIEs that
-/// describe variables or functions that are present in the linked
-/// binary (and thus have entries in the debug map). All the debug
-/// information that will be linked (the DIEs, but also the line
-/// tables, ranges, ...) is derived from that set of root DIEs.
-///
-/// The root DIEs are identified because they contain relocations that
-/// correspond to a debug map entry at specific places (the low_pc for
-/// a function, the location for a variable). These relocations are
-/// called ValidRelocs in the DwarfLinker and are gathered as a very
-/// first step when we start processing a DebugMapObject.
+/// driven by DWARFLinker. DwarfLinkerForBinary reads DebugMap objects
+/// and pass information to the DWARFLinker. DWARFLinker
+/// optimizes DWARF taking into account valid relocations.
+/// Finally, optimized DWARF is passed to DwarfLinkerForBinary through
+/// DWARFEmitter interface.
class DwarfLinkerForBinary {
public:
DwarfLinkerForBinary(raw_fd_ostream &OutFile, BinaryHolder &BinHolder,
@@ -46,7 +40,7 @@ class DwarfLinkerForBinary {
/// Link the contents of the DebugMap.
bool link(const DebugMap &);
- void reportWarning(const Twine &Warning, const DebugMapObject &DMO,
+ void reportWarning(const Twine &Warning, StringRef Context,
const DWARFDie *DIE = nullptr) const;
/// Flags passed to DwarfLinker::lookForDIEsToKeep
@@ -60,21 +54,9 @@ class DwarfLinkerForBinary {
};
private:
- /// Remembers the oldest and newest DWARF version we've seen in a unit.
- void updateDwarfVersion(unsigned Version) {
- MaxDwarfVersion = std::max(MaxDwarfVersion, Version);
- MinDwarfVersion = std::min(MinDwarfVersion, Version);
- }
-
- /// Remembers the kinds of accelerator tables we've seen in a unit.
- void updateAccelKind(DWARFContext &Dwarf);
-
- /// Emit warnings as Dwarf compile units to leave a trail after linking.
- bool emitPaperTrailWarnings(const DebugMapObject &DMO, const DebugMap &Map,
- OffsetsStringPool &StringPool);
/// Keeps track of relocations.
- class RelocationManager : public AddressesMap {
+ class AddressManager : public AddressesMap {
struct ValidReloc {
uint64_t Offset;
uint32_t Size;
@@ -105,8 +87,8 @@ class DwarfLinkerForBinary {
RangesTy AddressRanges;
public:
- RelocationManager(DwarfLinkerForBinary &Linker,
- const object::ObjectFile &Obj, const DebugMapObject &DMO)
+ AddressManager(DwarfLinkerForBinary &Linker, const object::ObjectFile &Obj,
+ const DebugMapObject &DMO)
: Linker(Linker) {
findValidRelocsInDebugInfo(Obj, DMO);
@@ -135,7 +117,7 @@ class DwarfLinkerForBinary {
int64_t(Mapping.BinaryAddress) - *Mapping.ObjectAddress);
}
}
- virtual ~RelocationManager() override { clear(); }
+ virtual ~AddressManager() override { clear(); }
virtual bool areRelocationsResolved() const override { return true; }
@@ -176,315 +158,7 @@ class DwarfLinkerForBinary {
}
};
- /// Keeps track of data associated with one object during linking.
- struct LinkContext {
- DwarfLinkerForBinary &Linker;
- DebugMapObject &DMO;
- const object::ObjectFile *ObjectFile = nullptr;
- std::unique_ptr<RelocationManager> RelocMgr;
- std::unique_ptr<DWARFContext> DwarfContext;
- RangesTy Ranges;
- UnitListTy CompileUnits;
-
- LinkContext(const DebugMap &Map, DwarfLinkerForBinary &Linker,
- DebugMapObject &DMO)
- : Linker(Linker), DMO(DMO) {
- // Swift ASTs are not object files.
- if (DMO.getType() == MachO::N_AST) {
- ObjectFile = nullptr;
- return;
- }
- if (auto ErrOrObj = Linker.loadObject(DMO, Map)) {
- ObjectFile = &*ErrOrObj;
- DwarfContext = DWARFContext::create(*ObjectFile);
- RelocMgr.reset(new RelocationManager(Linker, *ObjectFile, DMO));
- }
- }
-
- /// Clear part of the context that's no longer needed when we're done with
- /// the debug object.
- void Clear() {
- DwarfContext.reset(nullptr);
- CompileUnits.clear();
- Ranges.clear();
- RelocMgr->clear();
- }
- };
-
- /// Called at the start of a debug object link.
- void startDebugObject(LinkContext &Context);
-
- /// Called at the end of a debug object link.
- void endDebugObject(LinkContext &Context);
-
- /// \defgroup FindRootDIEs Find DIEs corresponding to debug map entries.
- ///
- /// @{
- /// Recursively walk the \p DIE tree and look for DIEs to
- /// keep. Store that information in \p CU's DIEInfo.
- ///
- /// The return value indicates whether the DIE is incomplete.
- void lookForDIEsToKeep(RelocationManager &RelocMgr, RangesTy &Ranges,
- const UnitListTy &Units, const DWARFDie &DIE,
- const DebugMapObject &DMO, CompileUnit &CU,
- unsigned Flags);
-
- /// If this compile unit is really a skeleton CU that points to a
- /// clang module, register it in ClangModules and return true.
- ///
- /// A skeleton CU is a CU without children, a DW_AT_gnu_dwo_name
- /// pointing to the module, and a DW_AT_gnu_dwo_id with the module
- /// hash.
- bool registerModuleReference(DWARFDie CUDie, const DWARFUnit &Unit,
- DebugMap &ModuleMap, const DebugMapObject &DMO,
- RangesTy &Ranges,
- OffsetsStringPool &OffsetsStringPool,
- UniquingStringPool &UniquingStringPoolStringPool,
- DeclContextTree &ODRContexts,
- uint64_t ModulesEndOffset, unsigned &UnitID,
- bool IsLittleEndian, unsigned Indent = 0,
- bool Quiet = false);
-
- /// Recursively add the debug info in this clang module .pcm
- /// file (and all the modules imported by it in a bottom-up fashion)
- /// to Units.
- Error loadClangModule(DWARFDie CUDie, StringRef FilePath,
- StringRef ModuleName, uint64_t DwoId,
- DebugMap &ModuleMap, const DebugMapObject &DMO,
- RangesTy &Ranges, OffsetsStringPool &OffsetsStringPool,
- UniquingStringPool &UniquingStringPool,
- DeclContextTree &ODRContexts, uint64_t ModulesEndOffset,
- unsigned &UnitID, bool IsLittleEndian,
- unsigned Indent = 0, bool Quiet = false);
-
- /// Mark the passed DIE as well as all the ones it depends on as kept.
- void keepDIEAndDependencies(RelocationManager &RelocMgr, RangesTy &Ranges,
- const UnitListTy &Units, const DWARFDie &DIE,
- CompileUnit::DIEInfo &MyInfo,
- const DebugMapObject &DMO, CompileUnit &CU,
- bool UseODR);
-
- unsigned shouldKeepDIE(RelocationManager &RelocMgr, RangesTy &Ranges,
- const DWARFDie &DIE, const DebugMapObject &DMO,
- CompileUnit &Unit, CompileUnit::DIEInfo &MyInfo,
- unsigned Flags);
-
- /// Check if a variable describing DIE should be kept.
- /// \returns updated TraversalFlags.
- unsigned shouldKeepVariableDIE(RelocationManager &RelocMgr,
- const DWARFDie &DIE, CompileUnit &Unit,
- CompileUnit::DIEInfo &MyInfo, unsigned Flags);
-
- unsigned shouldKeepSubprogramDIE(RelocationManager &RelocMgr,
- RangesTy &Ranges, const DWARFDie &DIE,
- const DebugMapObject &DMO, CompileUnit &Unit,
- CompileUnit::DIEInfo &MyInfo,
- unsigned Flags);
-
- bool hasValidRelocation(uint32_t StartOffset, uint32_t EndOffset,
- CompileUnit::DIEInfo &Info);
- /// @}
-
- /// \defgroup Linking Methods used to link the debug information
- ///
- /// @{
-
- class DIECloner {
- DwarfLinkerForBinary &Linker;
- RelocationManager &RelocMgr;
-
- /// Allocator used for all the DIEValue objects.
- BumpPtrAllocator &DIEAlloc;
-
- std::vector<std::unique_ptr<CompileUnit>> &CompileUnits;
- LinkOptions Options;
-
- public:
- DIECloner(DwarfLinkerForBinary &Linker, RelocationManager &RelocMgr,
- BumpPtrAllocator &DIEAlloc,
- std::vector<std::unique_ptr<CompileUnit>> &CompileUnits,
- LinkOptions &Options)
- : Linker(Linker), RelocMgr(RelocMgr), DIEAlloc(DIEAlloc),
- CompileUnits(CompileUnits), Options(Options) {}
-
- /// Recursively clone \p InputDIE into an tree of DIE objects
- /// where useless (as decided by lookForDIEsToKeep()) bits have been
- /// stripped out and addresses have been rewritten according to the
- /// debug map.
- ///
- /// \param OutOffset is the offset the cloned DIE in the output
- /// compile unit.
- /// \param PCOffset (while cloning a function scope) is the offset
- /// applied to the entry point of the function to get the linked address.
- /// \param Die the output DIE to use, pass NULL to create one.
- /// \returns the root of the cloned tree or null if nothing was selected.
- DIE *cloneDIE(const DWARFDie &InputDIE, const DebugMapObject &DMO,
- CompileUnit &U, OffsetsStringPool &StringPool,
- int64_t PCOffset, uint32_t OutOffset, unsigned Flags,
- bool IsLittleEndian, DIE *Die = nullptr);
-
- /// Construct the output DIE tree by cloning the DIEs we
- /// chose to keep above. If there are no valid relocs, then there's
- /// nothing to clone/emit.
- void cloneAllCompileUnits(DWARFContext &DwarfContext,
- const DebugMapObject &DMO, RangesTy &Ranges,
- OffsetsStringPool &StringPool,
- bool IsLittleEndian);
-
- private:
- using AttributeSpec = DWARFAbbreviationDeclaration::AttributeSpec;
-
- /// Information gathered and exchanged between the various
- /// clone*Attributes helpers about the attributes of a particular DIE.
- struct AttributesInfo {
- /// Names.
- DwarfStringPoolEntryRef Name, MangledName, NameWithoutTemplate;
-
- /// Offsets in the string pool.
- uint32_t NameOffset = 0;
- uint32_t MangledNameOffset = 0;
-
- /// Value of AT_low_pc in the input DIE
- uint64_t OrigLowPc = std::numeric_limits<uint64_t>::max();
-
- /// Value of AT_high_pc in the input DIE
- uint64_t OrigHighPc = 0;
-
- /// Offset to apply to PC addresses inside a function.
- int64_t PCOffset = 0;
-
- /// Does the DIE have a low_pc attribute?
- bool HasLowPc = false;
-
- /// Does the DIE have a ranges attribute?
- bool HasRanges = false;
-
- /// Is this DIE only a declaration?
- bool IsDeclaration = false;
-
- AttributesInfo() = default;
- };
-
- /// Helper for cloneDIE.
- unsigned cloneAttribute(DIE &Die, const DWARFDie &InputDIE,
- const DebugMapObject &DMO, CompileUnit &U,
- OffsetsStringPool &StringPool,
- const DWARFFormValue &Val,
- const AttributeSpec AttrSpec, unsigned AttrSize,
- AttributesInfo &AttrInfo, bool IsLittleEndian);
-
- /// Clone a string attribute described by \p AttrSpec and add
- /// it to \p Die.
- /// \returns the size of the new attribute.
- unsigned cloneStringAttribute(DIE &Die, AttributeSpec AttrSpec,
- const DWARFFormValue &Val, const DWARFUnit &U,
- OffsetsStringPool &StringPool,
- AttributesInfo &Info);
-
- /// Clone an attribute referencing another DIE and add
- /// it to \p Die.
- /// \returns the size of the new attribute.
- unsigned cloneDieReferenceAttribute(DIE &Die, const DWARFDie &InputDIE,
- AttributeSpec AttrSpec,
- unsigned AttrSize,
- const DWARFFormValue &Val,
- const DebugMapObject &DMO,
- CompileUnit &Unit);
-
- /// Clone a DWARF expression that may be referencing another DIE.
- void cloneExpression(DataExtractor &Data, DWARFExpression Expression,
- const DebugMapObject &DMO, CompileUnit &Unit,
- SmallVectorImpl<uint8_t> &OutputBuffer);
-
- /// Clone an attribute referencing another DIE and add
- /// it to \p Die.
- /// \returns the size of the new attribute.
- unsigned cloneBlockAttribute(DIE &Die, const DebugMapObject &DMO,
- CompileUnit &Unit, AttributeSpec AttrSpec,
- const DWARFFormValue &Val, unsigned AttrSize,
- bool IsLittleEndian);
-
- /// Clone an attribute referencing another DIE and add
- /// it to \p Die.
- /// \returns the size of the new attribute.
- unsigned cloneAddressAttribute(DIE &Die, AttributeSpec AttrSpec,
- const DWARFFormValue &Val,
- const CompileUnit &Unit,
- AttributesInfo &Info);
-
- /// Clone a scalar attribute and add it to \p Die.
- /// \returns the size of the new attribute.
- unsigned cloneScalarAttribute(DIE &Die, const DWARFDie &InputDIE,
- const DebugMapObject &DMO, CompileUnit &U,
- AttributeSpec AttrSpec,
- const DWARFFormValue &Val, unsigned AttrSize,
- AttributesInfo &Info);
-
- /// Get the potential name and mangled name for the entity
- /// described by \p Die and store them in \Info if they are not
- /// already there.
- /// \returns is a name was found.
- bool getDIENames(const DWARFDie &Die, AttributesInfo &Info,
- OffsetsStringPool &StringPool, bool StripTemplate = false);
-
- /// Create a copy of abbreviation Abbrev.
- void copyAbbrev(const DWARFAbbreviationDeclaration &Abbrev, bool hasODR);
-
- uint32_t hashFullyQualifiedName(DWARFDie DIE, CompileUnit &U,
- const DebugMapObject &DMO,
- int RecurseDepth = 0);
-
- /// Helper for cloneDIE.
- void addObjCAccelerator(CompileUnit &Unit, const DIE *Die,
- DwarfStringPoolEntryRef Name,
- OffsetsStringPool &StringPool, bool SkipPubSection);
- };
-
- /// Assign an abbreviation number to \p Abbrev
- void assignAbbrev(DIEAbbrev &Abbrev);
-
- /// Compute and emit debug_ranges section for \p Unit, and
- /// patch the attributes referencing it.
- void patchRangesForUnit(const CompileUnit &Unit, DWARFContext &Dwarf,
- const DebugMapObject &DMO) const;
-
- /// Generate and emit the DW_AT_ranges attribute for a compile_unit if it had
- /// one.
- void generateUnitRanges(CompileUnit &Unit) const;
-
- /// Extract the line tables from the original dwarf, extract the relevant
- /// parts according to the linked function ranges and emit the result in the
- /// debug_line section.
- void patchLineTableForUnit(CompileUnit &Unit, DWARFContext &OrigDwarf,
- RangesTy &Ranges, const DebugMapObject &DMO);
-
- /// Emit the accelerator entries for \p Unit.
- void emitAcceleratorEntriesForUnit(CompileUnit &Unit);
- void emitDwarfAcceleratorEntriesForUnit(CompileUnit &Unit);
- void emitAppleAcceleratorEntriesForUnit(CompileUnit &Unit);
-
- /// Patch the frame info for an object file and emit it.
- void patchFrameInfoForObject(const DebugMapObject &, RangesTy &Ranges,
- DWARFContext &, unsigned AddressSize);
-
- /// FoldingSet that uniques the abbreviations.
- FoldingSet<DIEAbbrev> AbbreviationsSet;
-
- /// Storage for the unique Abbreviations.
- /// This is passed to AsmPrinter::emitDwarfAbbrevs(), thus it cannot be
- /// changed to a vector of unique_ptrs.
- std::vector<std::unique_ptr<DIEAbbrev>> Abbreviations;
-
- /// DIELoc objects that need to be destructed (but not freed!).
- std::vector<DIELoc *> DIELocs;
-
- /// DIEBlock objects that need to be destructed (but not freed!).
- std::vector<DIEBlock *> DIEBlocks;
-
- /// Allocator used for all the DIEValue objects.
- BumpPtrAllocator DIEAlloc;
- /// @}
-
+private:
/// \defgroup Helpers Various helper methods.
///
/// @{
@@ -492,38 +166,16 @@ class DwarfLinkerForBinary {
/// Attempt to load a debug object from disk.
ErrorOr<const object::ObjectFile &> loadObject(const DebugMapObject &Obj,
- const DebugMap &Map);
- /// @}
+ const Triple &triple);
+ ErrorOr<DwarfLinkerObjFile &> loadObject(const DebugMapObject &Obj,
+ const DebugMap &DebugMap,
+ remarks::RemarkLinker &RL);
raw_fd_ostream &OutFile;
BinaryHolder &BinHolder;
LinkOptions Options;
std::unique_ptr<DwarfStreamer> Streamer;
-
- unsigned MaxDwarfVersion = 0;
- unsigned MinDwarfVersion = std::numeric_limits<unsigned>::max();
-
- bool AtLeastOneAppleAccelTable = false;
- bool AtLeastOneDwarfAccelTable = false;
-
- /// The CIEs that have been emitted in the output section. The actual CIE
- /// data serves a the key to this StringMap, this takes care of comparing the
- /// semantics of CIEs defined in
diff erent object files.
- StringMap<uint32_t> EmittedCIEs;
-
- /// Offset of the last CIE that has been emitted in the output
- /// debug_frame section.
- uint32_t LastCIEOffset = 0;
-
- /// Apple accelerator tables.
- AccelTable<DWARF5AccelTableStaticData> DebugNames;
- AccelTable<AppleAccelTableStaticOffsetData> AppleNames;
- AccelTable<AppleAccelTableStaticOffsetData> AppleNamespaces;
- AccelTable<AppleAccelTableStaticOffsetData> AppleObjc;
- AccelTable<AppleAccelTableStaticTypeData> AppleTypes;
-
- /// Mapping the PCM filename to the DwoId.
- StringMap<uint64_t> ClangModules;
+ std::vector<std::unique_ptr<DwarfLinkerObjFile>> ObjectsForLinking;
/// A list of all .swiftinterface files referenced by the debug
/// info, mapping Module name to path on disk. The entries need to
diff --git a/llvm/tools/dsymutil/DwarfStreamer.cpp b/llvm/tools/dsymutil/DwarfStreamer.cpp
index 3e132c29eada..de20d9a34788 100644
--- a/llvm/tools/dsymutil/DwarfStreamer.cpp
+++ b/llvm/tools/dsymutil/DwarfStreamer.cpp
@@ -784,12 +784,16 @@ void DwarfStreamer::emitPubSectionForUnit(
/// Emit .debug_pubnames for \p Unit.
void DwarfStreamer::emitPubNamesForUnit(const CompileUnit &Unit) {
+ if (Options.Minimize)
+ return;
emitPubSectionForUnit(MC->getObjectFileInfo()->getDwarfPubNamesSection(),
"names", Unit, Unit.getPubnames());
}
/// Emit .debug_pubtypes for \p Unit.
void DwarfStreamer::emitPubTypesForUnit(const CompileUnit &Unit) {
+ if (Options.Minimize)
+ return;
emitPubSectionForUnit(MC->getObjectFileInfo()->getDwarfPubTypesSection(),
"types", Unit, Unit.getPubtypes());
}
diff --git a/llvm/tools/dsymutil/LinkUtils.h b/llvm/tools/dsymutil/LinkUtils.h
index 0f31334cd317..92de81da8fa0 100644
--- a/llvm/tools/dsymutil/LinkUtils.h
+++ b/llvm/tools/dsymutil/LinkUtils.h
@@ -15,6 +15,7 @@
#include "llvm/Remarks/RemarkFormat.h"
#include "llvm/Support/WithColor.h"
+#include "llvm/DWARFLinker/DWARFLinker.h"
#include <string>
namespace llvm {
@@ -25,13 +26,6 @@ enum class OutputFileType {
Assembly,
};
-/// The kind of accelerator tables we should emit.
-enum class AccelTableKind {
- Apple, ///< .apple_names, .apple_namespaces, .apple_types, .apple_objc.
- Dwarf, ///< DWARF v5 .debug_names.
- Default, ///< Dwarf for DWARF5 or later, Apple otherwise.
-};
-
struct LinkOptions {
/// Verbosity
bool Verbose = false;
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