clang::PrecompiledPreamble Class Reference

A class holding a PCH and all information to check whether it is valid to reuse the PCH for the subsequent runs. More...

#include "clang/Frontend/PrecompiledPreamble.h"

Classes
class	PCHStorage

Public Member Functions
	PrecompiledPreamble (PrecompiledPreamble &&)
PrecompiledPreamble &	operator= (PrecompiledPreamble &&)
	~PrecompiledPreamble ()
PreambleBounds	getBounds () const
	PreambleBounds used to build the preamble.
std::size_t	getSize () const
	Returns the size, in bytes, that preamble takes on disk or in memory.
llvm::StringRef	getContents () const
	Returned string is not null-terminated.
bool	CanReuse (const CompilerInvocation &Invocation, const llvm::MemoryBufferRef &MainFileBuffer, PreambleBounds Bounds, llvm::vfs::FileSystem &VFS) const
	Check whether PrecompiledPreamble can be reused for the new contents(MainFileBuffer) of the main file.
void	AddImplicitPreamble (CompilerInvocation &CI, IntrusiveRefCntPtr< llvm::vfs::FileSystem > &VFS, llvm::MemoryBuffer *MainFileBuffer) const
	Changes options inside CI to use PCH from this preamble.
void	OverridePreamble (CompilerInvocation &CI, IntrusiveRefCntPtr< llvm::vfs::FileSystem > &VFS, llvm::MemoryBuffer *MainFileBuffer) const
	Configure CI to use this preamble.

Static Public Member Functions
static llvm::ErrorOr< PrecompiledPreamble >	Build (const CompilerInvocation &Invocation, const llvm::MemoryBuffer *MainFileBuffer, PreambleBounds Bounds, DiagnosticsEngine &Diagnostics, IntrusiveRefCntPtr< llvm::vfs::FileSystem > VFS, std::shared_ptr< PCHContainerOperations > PCHContainerOps, bool StoreInMemory, StringRef StoragePath, PreambleCallbacks &Callbacks)
	Try to build PrecompiledPreamble for Invocation.

Detailed Description

A class holding a PCH and all information to check whether it is valid to reuse the PCH for the subsequent runs.

Use BuildPreamble to create PCH and CanReusePreamble + AddImplicitPreamble to make use of it.

Definition at line 51 of file PrecompiledPreamble.h.

Constructor & Destructor Documentation

PrecompiledPreamble()

PrecompiledPreamble::PrecompiledPreamble ( PrecompiledPreamble &&  )

default

~PrecompiledPreamble()

PrecompiledPreamble::~PrecompiledPreamble ( )

default

Member Function Documentation

AddImplicitPreamble()

void PrecompiledPreamble::AddImplicitPreamble	(	CompilerInvocation &	CI,
		IntrusiveRefCntPtr< llvm::vfs::FileSystem > &	VFS,
		llvm::MemoryBuffer *	MainFileBuffer
	)		const

Changes options inside CI to use PCH from this preamble.

Also remaps main file to MainFileBuffer and updates VFS to ensure the preamble is accessible. Requires that CanReuse() is true. For in-memory preambles, PrecompiledPreamble instance continues to own the MemoryBuffer with the Preamble after this method returns. The caller is responsible for making sure the PrecompiledPreamble instance outlives the compiler run and the AST that will be using the PCH.

Definition at line 713 of file PrecompiledPreamble.cpp.

Build()

llvm::ErrorOr< PrecompiledPreamble > PrecompiledPreamble::Build ( const CompilerInvocation &  Invocation, const llvm::MemoryBuffer *  MainFileBuffer, PreambleBounds  Bounds, DiagnosticsEngine &  Diagnostics, IntrusiveRefCntPtr< llvm::vfs::FileSystem >  VFS, std::shared_ptr< PCHContainerOperations >  PCHContainerOps, bool  StoreInMemory, StringRef  StoragePath, PreambleCallbacks &  Callbacks  )

static

Try to build PrecompiledPreamble for Invocation.

See BuildPreambleError for possible error codes.

Parameters

Invocation	Original CompilerInvocation with options to compile the file.
MainFileBuffer	Buffer with the contents of the main file.
Bounds	Bounds of the preamble, result of calling ComputePreambleBounds.
Diagnostics	Diagnostics engine to be used while building the preamble.
VFS	An instance of vfs::FileSystem to be used for file accesses.
PCHContainerOps	An instance of PCHContainerOperations.
StoreInMemory	Store PCH in memory. If false, PCH will be stored in a temporary file.
StoragePath	The path to a directory, in which to create a temporary file to store PCH in. If empty, the default system temporary directory is used. This parameter is ignored if StoreInMemory is true.
Callbacks	A set of callbacks to be executed when building the preamble.

Definition at line 413 of file PrecompiledPreamble.cpp.

References clang::PreprocessorOptions::addRemappedFile(), clang::PreambleCallbacks::AfterExecute(), clang::BadInputs, clang::PreambleCallbacks::BeforeExecute(), clang::BeginSourceFileFailed, clang::CouldntCreateTargetInfo, clang::CouldntCreateTempFile, clang::CouldntEmitPCH, clang::PreambleCallbacks::createPPCallbacks(), clang::createVFSFromCompilerInvocation(), clang::File, clang::PrecompiledPreamble::PCHStorage::file(), Filename, clang::frontend::GeneratePCH, clang::PreprocessorOptions::GeneratePreamble, clang::PreambleCallbacks::getCommentHandler(), clang::SourceManager::getFileEntryRefForID(), clang::SourceManager::getFileManager(), clang::SourceManager::getMainFileID(), clang::SourceManager::getMemoryBufferForFileOrFake(), clang::FileManager::getOptionalFileRef(), clang::PrecompiledPreamble::PCHStorage::inMemory(), clang::FrontendOptions::Inputs, clang::LLVM_IR, clang::FrontendOptions::OutputFile, clang::PreambleBounds::PreambleEndsAtStartOfLine, clang::PreprocessorOptions::PrecompiledPreambleBytes, clang::ProcessWarningOptions(), clang::FrontendOptions::ProgramAction, clang::DiagnosticsEngine::Reset(), clang::PreprocessorOptions::RetainRemappedFileBuffers, clang::PreambleBounds::Size, and clang::InputKind::Source.

CanReuse()

bool PrecompiledPreamble::CanReuse	(	const CompilerInvocation &	Invocation,
		const llvm::MemoryBufferRef &	MainFileBuffer,
		PreambleBounds	Bounds,
		llvm::vfs::FileSystem &	VFS
	)		const

Check whether PrecompiledPreamble can be reused for the new contents(MainFileBuffer) of the main file.

Definition at line 602 of file PrecompiledPreamble.cpp.

References moveOnNoError(), clang::PreambleBounds::PreambleEndsAtStartOfLine, clang::PreprocessorOptions::RemappedFileBuffers, clang::PreprocessorOptions::RemappedFiles, and clang::PreambleBounds::Size.

getBounds()

PreambleBounds PrecompiledPreamble::getBounds

(

)

const

PreambleBounds used to build the preamble.

Definition at line 581 of file PrecompiledPreamble.cpp.

getContents()

llvm::StringRef clang::PrecompiledPreamble::getContents ( ) const

inline

Returned string is not null-terminated.

Definition at line 106 of file PrecompiledPreamble.h.

getSize()

std::size_t PrecompiledPreamble::getSize

(

)

const

Returns the size, in bytes, that preamble takes on disk or in memory.

For on-disk preambles returns 0 if filesystem operations fail. Intended to be used for logging and debugging purposes only.

Definition at line 585 of file PrecompiledPreamble.cpp.

References clang::Result.

operator=()

PrecompiledPreamble & PrecompiledPreamble::operator= ( PrecompiledPreamble &&  )

default

OverridePreamble()

void PrecompiledPreamble::OverridePreamble	(	CompilerInvocation &	CI,
		IntrusiveRefCntPtr< llvm::vfs::FileSystem > &	VFS,
		llvm::MemoryBuffer *	MainFileBuffer
	)		const

Configure CI to use this preamble.

Like AddImplicitPreamble, but doesn't assume CanReuse() is true. If this preamble does not match the file, it may parse differently.

Definition at line 720 of file PrecompiledPreamble.cpp.

References clang::ComputePreambleBounds(), and clang::CompilerInvocation::getLangOpts().

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

• include/clang/Frontend/PrecompiledPreamble.h
• lib/Frontend/PrecompiledPreamble.cpp