This class implements a resolution-based interface to LLVM's LTO functionality. More...

#include "llvm/LTO/LTO.h"

Inheritance diagram for llvm::lto::LTO:

Classes
struct	RegularLTOState
struct	ThinLTOState

Public Types
enum	LTOKind { LTOK_Default , LTOK_UnifiedRegular , LTOK_UnifiedThin }
	Unified LTO modes. More...

Public Member Functions
LLVM_ABI	LTO (Config Conf, ThinBackend Backend={}, unsigned ParallelCodeGenParallelismLevel=1, LTOKind LTOMode=LTOK_Default)
	Create an LTO object.
virtual LLVM_ABI	~LTO ()
LLVM_ABI Error	add (std::unique_ptr< InputFile > Obj, ArrayRef< SymbolResolution > Res)
	Add an input file to the LTO link, using the provided symbol resolutions.
LLVM_ABI void	setBitcodeLibFuncs (ArrayRef< StringRef > BitcodeLibFuncs)
	Set the list of functions implemented in bitcode that were not extracted from an archive.
LLVM_ABI unsigned	getMaxTasks () const
	Returns an upper bound on the number of tasks that the client may expect.
virtual LLVM_ABI Error	run (AddStreamFn AddStream, FileCache Cache={})
	Runs the LTO pipeline.
void	emitRemark (OptimizationRemark &Remark)
	Helper to emit an optimization remark during the LTO link when outside of the standard optimization pass pipeline.
virtual Expected< std::shared_ptr< lto::InputFile > >	addInput (std::unique_ptr< lto::InputFile > InputPtr)

Static Public Member Functions
static LLVM_ABI SmallVector< const char * >	getRuntimeLibcallSymbols (const Triple &TT)
	Static method that returns a list of libcall symbols that can be generated by LTO but might not be visible from bitcode symbol table.
static LLVM_ABI SmallVector< StringRef >	getLibFuncSymbols (const Triple &TT, llvm::StringSaver &Saver)
	Static method that returns a list of library function symbols that can be generated by LTO but might not be visible from bitcode symbol table.

Protected Types
using	ModuleMapType = MapVector<StringRef, BitcodeModule>

Protected Member Functions
virtual void	cleanup ()

Protected Attributes
Config	Conf
struct llvm::lto::LTO::RegularLTOState	RegularLTO
struct llvm::lto::LTO::ThinLTOState	ThinLTO
LTOKind	LTOMode

Detailed Description

This class implements a resolution-based interface to LLVM's LTO functionality.

It supports regular LTO, parallel LTO code generation and ThinLTO. You can use it from a linker in the following way:

Set hooks and code generation options (see lto::Config struct defined in Config.h), and use the lto::Config object to create an lto::LTO object.
Create lto::InputFile objects using lto::InputFile::create(), then use the symbols() function to enumerate its symbols and compute a resolution for each symbol (see SymbolResolution below).
After the linker has visited each input file (and each regular object file) and computed a resolution for each symbol, take each lto::InputFile and pass it and an array of symbol resolutions to the add() function.
Call the getMaxTasks() function to get an upper bound on the number of native object files that LTO may add to the link.
Call the run() function. This function will use the supplied AddStream and Cache functions to add up to getMaxTasks() native object files to the link.

Definition at line 390 of file LTO.h.

Member Typedef Documentation

◆ ModuleMapType

using llvm::lto::LTO::ModuleMapType = MapVector<StringRef, BitcodeModule>

protected

Definition at line 489 of file LTO.h.

Member Enumeration Documentation

◆ LTOKind

enum llvm::lto::LTO::LTOKind

Unified LTO modes.

Enumerator
LTOK_Default	Any LTO mode without Unified LTO. The default mode.
LTOK_UnifiedRegular	Regular LTO, with Unified LTO enabled.
LTOK_UnifiedThin	ThinLTO, with Unified LTO enabled.

Definition at line 395 of file LTO.h.

Constructor & Destructor Documentation

◆ LTO()

LTO::LTO	(	Config	Conf,
		ThinBackend	Backend = {},
		unsigned	ParallelCodeGenParallelismLevel = 1,
		LTOKind	LTOMode = LTOK_Default )

Create an LTO object.

A default constructed LTO object has a reasonable production configuration, but you can customize it by passing arguments to this constructor. FIXME: We do currently require the DiagHandler field to be set in Conf. Until that is fixed, a Config argument is required.

Definition at line 688 of file LTO.cpp.

References Conf, llvm::LTOKeepSymbolCopies, LTOMode, llvm::move(), RegularLTO, and ThinLTO.

◆ ~LTO()

LTO::~LTO ( )

virtualdefault

References LLVM_ABI.

Member Function Documentation

◆ add()

Error LTO::add	(	std::unique_ptr< InputFile >	Obj,
		ArrayRef< SymbolResolution >	Res )

Add an input file to the LTO link, using the provided symbol resolutions.

The symbol resolutions must appear in the enumeration order given by InputFile::symbols().

Definition at line 822 of file LTO.cpp.

References addInput(), assert(), Conf, llvm::lto::Config::ELF, llvm::ArrayRef< T >::empty(), I, llvm::Triple::isOSBinFormatELF(), RegularLTO, llvm::Error::success(), llvm::Expected< T >::takeError(), and writeToResolutionFile().

◆ addInput()

virtual Expected< std::shared_ptr< lto::InputFile > > llvm::lto::LTO::addInput ( std::unique_ptr< lto::InputFile > InputPtr )

inlinevirtual

Definition at line 656 of file LTO.h.

Referenced by add().

◆ cleanup()

void LTO::cleanup ( )

protectedvirtual

Definition at line 705 of file LTO.cpp.

References llvm::consumeError(), and llvm::lto::finalizeOptimizationRemarks().

Referenced by run().

◆ emitRemark()

void LTO::emitRemark ( OptimizationRemark & Remark )

Helper to emit an optimization remark during the LTO link when outside of the standard optimization pass pipeline.

Definition at line 101 of file LTO.cpp.

References llvm::OptimizationRemarkEmitter::emit(), F, and llvm::Remark.

◆ getLibFuncSymbols()

SmallVector< StringRef > LTO::getLibFuncSymbols	(	const Triple &	TT,
		llvm::StringSaver &	Saver )

static

Static method that returns a list of library function symbols that can be generated by LTO but might not be visible from bitcode symbol table.

Unlike the runtime libcalls, the linker can report to the code generator which of these are actually available in the link, and the code generator can then only reference that set of symbols.

Definition at line 1505 of file LTO.cpp.

References llvm::StringRef::data(), F, llvm::TargetLibraryInfo::getName(), llvm::TargetLibraryInfo::has(), I, llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::SmallVectorImpl< T >::reserve(), and llvm::StringSaver::save().

◆ getMaxTasks()

unsigned LTO::getMaxTasks ( ) const

Returns an upper bound on the number of tasks that the client may expect.

This may only be called after all IR object files have been added. For a full description of tasks see LTOBackend.h.

Definition at line 1250 of file LTO.cpp.

References RegularLTO, and ThinLTO.

◆ getRuntimeLibcallSymbols()

SmallVector< const char * > LTO::getRuntimeLibcallSymbols ( const Triple & TT )

static

Static method that returns a list of libcall symbols that can be generated by LTO but might not be visible from bitcode symbol table.

Definition at line 1492 of file LTO.cpp.

References llvm::StringRef::data(), llvm::RTLIB::RuntimeLibcallsInfo::getLibcallImplName(), llvm::RTLIB::RuntimeLibcallsInfo::getNumAvailableLibcallImpls(), llvm::RTLIB::RuntimeLibcallsInfo::isAvailable(), llvm::RTLIB::libcall_impls(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), and llvm::SmallVectorImpl< T >::reserve().

◆ run()

Error LTO::run	(	AddStreamFn	AddStream,
		FileCache	Cache = {} )

virtual

Runs the LTO pipeline.

This function calls the supplied AddStream function to add native object files to the link.

The Cache parameter is optional. If supplied, it will be used to cache native object files and add them to the link.

The client will receive at most one callback (via either AddStream or Cache) for each task identifier.

Reimplemented in llvm::lto::DTLTO.

Definition at line 1301 of file LTO.cpp.

References cleanup(), llvm::computeDeadSymbolsWithConstProp(), Conf, llvm::GlobalValue::dropLLVMManglingEscape(), llvm::ArrayRef< T >::empty(), llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::end(), llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::find(), G, llvm::GlobalValue::getGUIDAssumingExternalLinkage(), llvm::No, llvm::PrintStatisticsJSON(), llvm::lto::setupStatsFile(), llvm::SupportsHotColdNew, ThinLTO, llvm::Unknown, and llvm::Yes.

◆ setBitcodeLibFuncs()

void LTO::setBitcodeLibFuncs ( ArrayRef< StringRef > BitcodeLibFuncs )

Set the list of functions implemented in bitcode that were not extracted from an archive.

Such functions may not be referenced, as they have lost their opportunity to be defined.

Definition at line 853 of file LTO.cpp.

References assert(), and llvm::ArrayRef< T >::empty().

Member Data Documentation

◆ Conf

Config llvm::lto::LTO::Conf

protected

Definition at line 459 of file LTO.h.

Referenced by add(), llvm::lto::DTLTO::DTLTO(), llvm::lto::DTLTO::getConfig(), llvm::lto::DTLTO::getConfig(), LTO(), llvm::lto::LTO::RegularLTOState::RegularLTOState(), llvm::lto::DTLTO::run(), and run().

◆ LTOMode

LTOKind llvm::lto::LTO::LTOMode

protected

Definition at line 620 of file LTO.h.

Referenced by llvm::lto::DTLTO::DTLTO(), and LTO().

◆ RegularLTO

struct llvm::lto::LTO::RegularLTOState llvm::lto::LTO::RegularLTO

protected

Referenced by add(), getMaxTasks(), LTO(), and llvm::lto::DTLTO::run().

◆ ThinLTO

struct llvm::lto::LTO::ThinLTOState llvm::lto::LTO::ThinLTO

protected

Referenced by getMaxTasks(), LTO(), and run().

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

include/llvm/LTO/LTO.h
lib/LTO/LTO.cpp

Classes

Public Types

Public Member Functions

Static Public Member Functions

Protected Types

Protected Member Functions

Protected Attributes

Detailed Description

Member Typedef Documentation

◆ ModuleMapType

Member Enumeration Documentation

◆ LTOKind

Constructor & Destructor Documentation

◆ LTO()

◆ ~LTO()

Member Function Documentation

◆ add()

◆ addInput()

◆ cleanup()

◆ emitRemark()

◆ getLibFuncSymbols()

◆ getMaxTasks()

◆ getRuntimeLibcallSymbols()

◆ run()

◆ setBitcodeLibFuncs()

Member Data Documentation

◆ Conf

◆ LTOMode

◆ RegularLTO

◆ ThinLTO