Keeps track of data associated with one object during linking. More...

#include "DWARFLinker/Parallel/DWARFLinkerImpl.h"

Inheritance diagram for llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext:

Classes
struct	CIELocation
	Section + local offset of a .debug_frame CIE that has been (or will be) emitted by some LinkContext. More...
struct	FrameScanResult
	Result of scanning one LinkContext's input .debug_frame. More...

Public Types
using	UnitListTy = SmallVector<std::unique_ptr<CompileUnit>>
using	CIERegistry = StringMap<CIELocation>
	Linker-wide registry for .debug_frame CIEs.

Public Member Functions
	LinkContext (LinkingGlobalData &GlobalData, DWARFFile &File, uint64_t ObjFileIdx, StringMap< uint64_t > &ClangModules, std::atomic< size_t > &UniqueUnitID)
std::pair< bool, bool >	isClangModuleRef (const DWARFDie &CUDie, std::string &PCMFile, unsigned Indent, bool Quiet)
	Check whether specified `CUDie` is a Clang module reference.
bool	registerModuleReference (const DWARFDie &CUDie, ObjFileLoaderTy Loader, CompileUnitHandlerTy OnCUDieLoaded, unsigned Indent=0)
	If this compile unit is really a skeleton CU that points to a clang module, register it in ClangModules and return true.
Error	loadClangModule (ObjFileLoaderTy Loader, const DWARFDie &CUDie, const std::string &PCMFile, CompileUnitHandlerTy OnCUDieLoaded, unsigned Indent=0)
	Recursively add the debug info in this clang module .pcm file (and all the modules imported by it in a bottom-up fashion) to ModuleUnits.
uint64_t	getInputDebugInfoSize () const
	Computes the total size of the debug info.
Error	link (TypeUnit *ArtificialTypeUnit)
	Link compile units for this context.
void	linkSingleCompileUnit (CompileUnit &CU, TypeUnit *ArtificialTypeUnit, enum CompileUnit::Stage DoUntilStage=CompileUnit::Stage::Cleaned)
	Link specified compile unit until specified stage.
Error	emitInvariantSections ()
	Emit invariant sections.
Error	unloadInput ()
	Unload the input DWARFContext after scanning the input .debug_frame into FrameScan.
Error	scanFrameData ()
	Parse this context's input .debug_frame into FrameScan.
void	registerCIEs (CIERegistry &CIEs)
	Register this context's CIEs with the linker-wide registry.
Error	emitDebugFrame (const CIERegistry &CIEs)
	Emit this context's .debug_frame section.
void	emitFDE (uint32_t CIEOffset, uint32_t AddrSize, uint64_t Address, StringRef FDEBytes, SectionDescriptor &Section)
	Emit FDE record.
Public Member Functions inherited from llvm::dwarf_linker::parallel::OutputSections
	OutputSections (LinkingGlobalData &GlobalData)
void	setOutputFormat (dwarf::FormParams Format, llvm::endianness Endianness)
	Sets output format for all keeping sections.
const SectionDescriptor &	getSectionDescriptor (DebugSectionKind SectionKind) const
	Returns descriptor for the specified section of `SectionKind`.
SectionDescriptor &	getSectionDescriptor (DebugSectionKind SectionKind)
	Returns descriptor for the specified section of `SectionKind`.
std::optional< const SectionDescriptor * >	tryGetSectionDescriptor (DebugSectionKind SectionKind) const
	Returns descriptor for the specified section of `SectionKind`.
std::optional< SectionDescriptor * >	tryGetSectionDescriptor (DebugSectionKind SectionKind)
	Returns descriptor for the specified section of `SectionKind`.
SectionDescriptor &	getOrCreateSectionDescriptor (DebugSectionKind SectionKind)
	Returns descriptor for the specified section of `SectionKind`.
void	eraseSections ()
	Erases data of all sections.
void	forEach (function_ref< void(SectionDescriptor &)> Handler)
	Enumerate all sections and call `Handler` for each.
void	forEach (function_ref< void(std::shared_ptr< SectionDescriptor > Section)> Handler)
	Enumerate all sections and call `Handler` for each.
void	assignSectionsOffsetAndAccumulateSize (std::array< uint64_t, SectionKindsNum > &SectionSizesAccumulator)
	Enumerate all sections, for each section set current offset (kept by `SectionSizesAccumulator`), update current offset with section length.
void	applyPatches (SectionDescriptor &Section, StringEntryToDwarfStringPoolEntryMap &DebugStrStrings, StringEntryToDwarfStringPoolEntryMap &DebugLineStrStrings, TypeUnit *TypeUnitPtr)
	Enumerate all sections, for each section apply all section patches.
llvm::endianness	getEndianness () const
	Endiannes for the sections.
uint16_t	getVersion () const
	Return DWARF version.
uint16_t	getDebugInfoHeaderSize () const
	Return size of header of debug_info table.
uint16_t	getDebugAddrHeaderSize () const
	Return size of header of debug_ table.
uint16_t	getDebugStrOffsetsHeaderSize () const
	Return size of header of debug_str_offsets table.
const dwarf::FormParams &	getFormParams () const
	Return size of address.

Public Attributes
DWARFFile &	InputDWARFFile
	Object file descriptor.
UnitListTy	CompileUnits
	Set of Compilation Units(may be accessed asynchroniously for reading).
UnitListTy	ModulesCompileUnits
	Set of Compile Units for modules.
uint64_t	ObjectFileIdx = 0
	Index of this object file in the link order (used for deterministic type DIE allocation).
uint64_t	OriginalDebugInfoSize = 0
	Size of Debug info before optimizing.
bool	InterCUProcessingStarted = false
	Flag indicating that all inter-connected units are loaded and the dwarf linking process for these units is started.
StringMap< uint64_t > &	ClangModules
std::atomic< bool >	HasNewInterconnectedCUs = {false}
	Flag indicating that new inter-connected compilation units were discovered.
std::atomic< bool >	HasNewGlobalDependency = {false}
std::atomic< size_t > &	UniqueUnitID
	Counter for compile units ID.
std::unique_ptr< FrameScanResult >	FrameScan
std::function< CompileUnit *(uint64_t)>	getUnitForOffset

Additional Inherited Members
Protected Types inherited from llvm::dwarf_linker::parallel::OutputSections
using	SectionsSetTy
	All keeping sections.
Protected Attributes inherited from llvm::dwarf_linker::parallel::OutputSections
LinkingGlobalData &	GlobalData
dwarf::FormParams	Format = {4, 4, dwarf::DWARF32}
	Format for sections.
llvm::endianness	Endianness = llvm::endianness::native
	Endiannes for sections.
SectionsSetTy	SectionDescriptors

Detailed Description

Keeps track of data associated with one object during linking.

i.e. source file descriptor, compilation units, output data for compilation units common tables.

Definition at line 158 of file DWARFLinkerImpl.h.

Member Typedef Documentation

◆ CIERegistry

using llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext::CIERegistry = StringMap<CIELocation>

Linker-wide registry for .debug_frame CIEs.

The key is the raw CIE bytes. Populated by a serial pass over ObjectContexts (so ownership is deterministic — first LinkContext wins) and then consumed read-only by a parallel emission pass that writes each context's .debug_frame section. SectionDescriptor pointers remain valid until linking completes because they live in std::map-held shared_ptrs.

Definition at line 252 of file DWARFLinkerImpl.h.

◆ UnitListTy

using llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext::UnitListTy = SmallVector<std::unique_ptr<CompileUnit>>

Definition at line 159 of file DWARFLinkerImpl.h.

Constructor & Destructor Documentation

◆ LinkContext()

DWARFLinkerImpl::LinkContext::LinkContext	(	LinkingGlobalData &	GlobalData,
		DWARFFile &	File,
		uint64_t	ObjFileIdx,
		StringMap< uint64_t > &	ClangModules,
		std::atomic< size_t > &	UniqueUnitID )

Definition at line 29 of file DWARFLinkerImpl.cpp.

References ClangModules, llvm::dwarf_linker::parallel::OutputSections::GlobalData, InputDWARFFile, ObjectFileIdx, llvm::dwarf_linker::parallel::OutputSections::OutputSections(), and UniqueUnitID.

Member Function Documentation

◆ emitDebugFrame()

Error DWARFLinkerImpl::LinkContext::emitDebugFrame ( const CIERegistry & CIEs )

Emit this context's .debug_frame section.

Safe to call in parallel across contexts because each call writes only to its own SectionDescriptor.

Definition at line 894 of file DWARFLinkerImpl.cpp.

References llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext::FrameScanResult::FDE::Address, assert(), llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext::FrameScanResult::FDE::CIEBytes, llvm::createFileError(), llvm::createStringError(), llvm::dwarf_linker::DebugFrame, emitFDE(), llvm::StringMap< ValueTy, AllocatorTy >::end(), llvm::StringMap< ValueTy, AllocatorTy >::find(), llvm::dwarf::FormatString(), FP, FrameScan, llvm::dwarf_linker::parallel::SectionDescriptorBase::getFormParams(), llvm::dwarf_linker::parallel::OutputSections::getSectionDescriptor(), InputDWARFFile, llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext::FrameScanResult::FDE::Instructions, llvm::dwarf_linker::parallel::SectionDescriptor::OS, llvm::Error::success(), llvm::raw_ostream::tell(), and llvm::Twine::utohexstr().

◆ emitFDE()

void DWARFLinkerImpl::LinkContext::emitFDE	(	uint32_t	CIEOffset,
		uint32_t	AddrSize,
		uint64_t	Address,
		StringRef	FDEBytes,
		SectionDescriptor &	Section )

Emit FDE record.

Emit a FDE into the debug_frame section.

FDEBytes contains the FDE data without the length, CIE offset and address which will be replaced with the parameter values.

Definition at line 950 of file DWARFLinkerImpl.cpp.

References llvm::Address, llvm::StringRef::data(), and llvm::StringRef::size().

Referenced by emitDebugFrame().

◆ emitInvariantSections()

Error DWARFLinkerImpl::LinkContext::emitInvariantSections ( )

Emit invariant sections.

Definition at line 745 of file DWARFLinkerImpl.cpp.

References llvm::dwarf_linker::DebugAddr, llvm::dwarf_linker::DebugARanges, llvm::dwarf_linker::DebugFrame, llvm::dwarf_linker::DebugLoc, llvm::dwarf_linker::DebugLocLists, llvm::dwarf_linker::DebugRange, llvm::dwarf_linker::DebugRngLists, llvm::dwarf_linker::parallel::OutputSections::getOrCreateSectionDescriptor(), llvm::dwarf_linker::parallel::OutputSections::GlobalData, InputDWARFFile, and llvm::Error::success().

Referenced by link().

◆ getInputDebugInfoSize()

uint64_t llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext::getInputDebugInfoSize ( ) const

inline

Computes the total size of the debug info.

Definition at line 224 of file DWARFLinkerImpl.h.

References InputDWARFFile, Size, and uint64_t.

Referenced by link().

◆ isClangModuleRef()

std::pair< bool, bool > DWARFLinkerImpl::LinkContext::isClangModuleRef	(	const DWARFDie &	CUDie,
		std::string &	PCMFile,
		unsigned	Indent,
		bool	Quiet )

Check whether specified CUDie is a Clang module reference.

if Quiet is false then display error messages.

Returns: first == true if CUDie is a Clang module reference. second == true if module is already loaded.

Definition at line 331 of file DWARFLinkerImpl.cpp.

References ClangModules, llvm::DWARFDie::find(), llvm::getDwoId(), llvm::dwarf_linker::parallel::OutputSections::GlobalData, llvm::raw_ostream::indent(), InputDWARFFile, llvm::outs(), llvm::Quiet, and llvm::dwarf::toString().

Referenced by link(), and registerModuleReference().

◆ link()

Error DWARFLinkerImpl::LinkContext::link ( TypeUnit * ArtificialTypeUnit )

Link compile units for this context.

Definition at line 481 of file DWARFLinkerImpl.cpp.

◆ linkSingleCompileUnit()

void DWARFLinkerImpl::LinkContext::linkSingleCompileUnit	(	CompileUnit &	CU,
		TypeUnit *	ArtificialTypeUnit,
		enum CompileUnit::Stage	DoUntilStage = CompileUnit::Stage::Cleaned )

Link specified compile unit until specified stage.

Definition at line 627 of file DWARFLinkerImpl.cpp.

Referenced by link().

◆ loadClangModule()

Error DWARFLinkerImpl::LinkContext::loadClangModule	(	ObjFileLoaderTy	Loader,
		const DWARFDie &	CUDie,
		const std::string &	PCMFile,
		CompileUnitHandlerTy	OnCUDieLoaded,
		unsigned	Indent = 0 )

Recursively add the debug info in this clang module .pcm file (and all the modules imported by it in a bottom-up fashion) to ModuleUnits.

Using a SmallString<0> because loadClangModule() is recursive.

Definition at line 406 of file DWARFLinkerImpl.cpp.

References llvm::sys::path::append(), ClangModules, llvm::DWARFDie::find(), llvm::getDwoId(), llvm::dwarf_linker::parallel::OutputSections::getEndianness(), getUnitForOffset, llvm::dwarf_linker::parallel::OutputSections::GlobalData, llvm::inconvertibleErrorCode(), InputDWARFFile, llvm::sys::path::is_relative(), llvm::make_error(), ModulesCompileUnits, registerModuleReference(), llvm::resolveRelativeObjectPath(), llvm::Error::success(), llvm::dwarf::toString(), and UniqueUnitID.

Referenced by registerModuleReference().

◆ registerCIEs()

void DWARFLinkerImpl::LinkContext::registerCIEs ( CIERegistry & CIEs )

Register this context's CIEs with the linker-wide registry.

Definition at line 878 of file DWARFLinkerImpl.cpp.

References assert(), llvm::dwarf_linker::DebugFrame, FrameScan, llvm::dwarf_linker::parallel::OutputSections::getOrCreateSectionDescriptor(), llvm::StringRef::size(), and llvm::StringMap< ValueTy, AllocatorTy >::try_emplace().

◆ registerModuleReference()

bool DWARFLinkerImpl::LinkContext::registerModuleReference	(	const DWARFDie &	CUDie,
		ObjFileLoaderTy	Loader,
		CompileUnitHandlerTy	OnCUDieLoaded,
		unsigned	Indent = 0 )

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.

Definition at line 377 of file DWARFLinkerImpl.cpp.

References ClangModules, llvm::consumeError(), llvm::getDwoId(), llvm::getPCMFile(), llvm::dwarf_linker::parallel::OutputSections::GlobalData, isClangModuleRef(), loadClangModule(), and llvm::outs().

Referenced by linkSingleCompileUnit(), and loadClangModule().

◆ scanFrameData()

Error DWARFLinkerImpl::LinkContext::scanFrameData ( )

Parse this context's input .debug_frame into FrameScan.

Deferred CIE/FDE emission happens later against the scan result alone.

Definition at line 767 of file DWARFLinkerImpl.cpp.

References CompileUnits, llvm::createFileError(), llvm::createStringError(), llvm::Data, llvm::DWARFSection::Data, llvm::StringRef::empty(), FrameScan, llvm::DWARFObject::getAddressSize(), llvm::DWARFObject::getFrameSection(), llvm::AddressRangesBase< T >::getRangeThatContains(), llvm::dwarf_linker::parallel::OutputSections::GlobalData, InputDWARFFile, llvm::AddressRangesMap::insert(), llvm::detail::DenseSetImpl< ValueT, MapTy >::insert(), llvm::DWARFObject::isLittleEndian(), llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::lookup(), Range, llvm::StringRef::size(), llvm::StringRef::substr(), and llvm::Error::success().

Referenced by unloadInput().

◆ unloadInput()

Error DWARFLinkerImpl::LinkContext::unloadInput ( )

Unload the input DWARFContext after scanning the input .debug_frame into FrameScan.

Definition at line 938 of file DWARFLinkerImpl.cpp.

References InputDWARFFile, and scanFrameData().

Member Data Documentation

◆ ClangModules

StringMap<uint64_t>& llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext::ClangModules

Definition at line 181 of file DWARFLinkerImpl.h.

Referenced by isClangModuleRef(), LinkContext(), loadClangModule(), and registerModuleReference().

◆ CompileUnits

UnitListTy llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext::CompileUnits

Set of Compilation Units(may be accessed asynchroniously for reading).

Definition at line 165 of file DWARFLinkerImpl.h.

Referenced by link(), and scanFrameData().

◆ FrameScan

std::unique_ptr<FrameScanResult> llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext::FrameScan

Definition at line 287 of file DWARFLinkerImpl.h.

Referenced by emitDebugFrame(), registerCIEs(), and scanFrameData().

◆ getUnitForOffset

std::function<CompileUnit *(uint64_t)> llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext::getUnitForOffset

Initial value:

=
        [&](uint64_t Offset) -> CompileUnit * {
      auto CU = llvm::upper_bound(
          CompileUnits, Offset,
          [](uint64_t LHS, const std::unique_ptr<CompileUnit> &RHS) {
            return LHS < RHS->getOrigUnit().getNextUnitOffset();
          });
 
      return CU != CompileUnits.end() ? CU->get() : nullptr;
    }

Definition at line 320 of file DWARFLinkerImpl.h.

Referenced by link(), and loadClangModule().

◆ HasNewGlobalDependency

std::atomic<bool> llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext::HasNewGlobalDependency = {false}

Definition at line 188 of file DWARFLinkerImpl.h.

Referenced by link(), and linkSingleCompileUnit().

◆ HasNewInterconnectedCUs

std::atomic<bool> llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext::HasNewInterconnectedCUs = {false}

Flag indicating that new inter-connected compilation units were discovered.

It is used for restarting units processing if new inter-connected units were found.

Definition at line 186 of file DWARFLinkerImpl.h.

Referenced by link(), and linkSingleCompileUnit().

◆ InputDWARFFile

DWARFFile& llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext::InputDWARFFile

Object file descriptor.

Definition at line 162 of file DWARFLinkerImpl.h.

Referenced by emitDebugFrame(), emitInvariantSections(), getInputDebugInfoSize(), isClangModuleRef(), link(), LinkContext(), loadClangModule(), scanFrameData(), and unloadInput().

◆ InterCUProcessingStarted

bool llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext::InterCUProcessingStarted = false

Flag indicating that all inter-connected units are loaded and the dwarf linking process for these units is started.

Definition at line 179 of file DWARFLinkerImpl.h.

Referenced by link(), and linkSingleCompileUnit().

◆ ModulesCompileUnits

UnitListTy llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext::ModulesCompileUnits

Set of Compile Units for modules.

Definition at line 168 of file DWARFLinkerImpl.h.

Referenced by link(), and loadClangModule().

◆ ObjectFileIdx

uint64_t llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext::ObjectFileIdx = 0

Index of this object file in the link order (used for deterministic type DIE allocation).

Definition at line 172 of file DWARFLinkerImpl.h.

Referenced by link(), and LinkContext().

◆ OriginalDebugInfoSize

uint64_t llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext::OriginalDebugInfoSize = 0

Size of Debug info before optimizing.

Definition at line 175 of file DWARFLinkerImpl.h.

Referenced by link().

◆ UniqueUnitID

std::atomic<size_t>& llvm::dwarf_linker::parallel::DWARFLinkerImpl::LinkContext::UniqueUnitID

Counter for compile units ID.

Definition at line 191 of file DWARFLinkerImpl.h.

Referenced by link(), LinkContext(), and loadClangModule().

The documentation for this struct was generated from the following files:

lib/DWARFLinker/Parallel/DWARFLinkerImpl.h
lib/DWARFLinker/Parallel/DWARFLinkerImpl.cpp

Classes

Public Types

Public Member Functions

Public Attributes

Additional Inherited Members

Detailed Description

Member Typedef Documentation

◆ CIERegistry

◆ UnitListTy

Constructor & Destructor Documentation

◆ LinkContext()

Member Function Documentation

◆ emitDebugFrame()

◆ emitFDE()

◆ emitInvariantSections()

◆ getInputDebugInfoSize()

◆ isClangModuleRef()

◆ link()

◆ linkSingleCompileUnit()

◆ loadClangModule()

◆ registerCIEs()

◆ registerModuleReference()

◆ scanFrameData()

◆ unloadInput()

Member Data Documentation

◆ ClangModules

◆ CompileUnits

◆ FrameScan

◆ getUnitForOffset

◆ HasNewGlobalDependency

◆ HasNewInterconnectedCUs

◆ InputDWARFFile

◆ InterCUProcessingStarted

◆ ModulesCompileUnits

◆ ObjectFileIdx

◆ OriginalDebugInfoSize

◆ UniqueUnitID