clang-tools  14.0.0git
Public Member Functions | List of all members
clang::clangd::PreambleFileStatusCache Class Reference

Records status information for files open()ed or stat()ed during preamble build (except for the main file), so we can avoid stat()s on the underlying FS when reusing the preamble. More...

#include <FS.h>

Public Member Functions

 PreambleFileStatusCache (llvm::StringRef MainFilePath)
 MainFilePath is the absolute path of the main source file this preamble corresponds to. More...
 
void update (const llvm::vfs::FileSystem &FS, llvm::vfs::Status S)
 
llvm::Optional< llvm::vfs::Status > lookup (llvm::StringRef Path) const
 Path is a path stored in preamble. More...
 
IntrusiveRefCntPtr< llvm::vfs::FileSystem > getProducingFS (IntrusiveRefCntPtr< llvm::vfs::FileSystem > FS)
 Returns a VFS that collects file status. More...
 
IntrusiveRefCntPtr< llvm::vfs::FileSystem > getConsumingFS (IntrusiveRefCntPtr< llvm::vfs::FileSystem > FS) const
 Returns a VFS that uses the cache collected. More...
 

Detailed Description

Records status information for files open()ed or stat()ed during preamble build (except for the main file), so we can avoid stat()s on the underlying FS when reusing the preamble.

For example, code completion can re-stat files when getting FileID for source locations stored in preamble (e.g. checking whether a location is in the main file).

The cache is keyed by absolute path of file name in cached status, as this is what preamble stores.

The cache is not thread-safe when updates happen, so the use pattern should be:

Note that the cache is only valid when reusing preamble.

Definition at line 38 of file FS.h.

Constructor & Destructor Documentation

◆ PreambleFileStatusCache()

clang::clangd::PreambleFileStatusCache::PreambleFileStatusCache ( llvm::StringRef  MainFilePath)

MainFilePath is the absolute path of the main source file this preamble corresponds to.

The stat for the main file will not be cached.

Definition at line 18 of file FS.cpp.

Member Function Documentation

◆ getConsumingFS()

llvm::IntrusiveRefCntPtr< llvm::vfs::FileSystem > clang::clangd::PreambleFileStatusCache::getConsumingFS ( IntrusiveRefCntPtr< llvm::vfs::FileSystem >  FS) const

Returns a VFS that uses the cache collected.

Note that the returned VFS should not outlive the cache.

Definition at line 94 of file FS.cpp.

◆ getProducingFS()

llvm::IntrusiveRefCntPtr< llvm::vfs::FileSystem > clang::clangd::PreambleFileStatusCache::getProducingFS ( IntrusiveRefCntPtr< llvm::vfs::FileSystem >  FS)

Returns a VFS that collects file status.

Only cache stats for files that exist because 1) we only care about existing files when reusing preamble, unlike building preamble. 2) we use the file name in the Status as the cache key.

Note that the returned VFS should not outlive the cache.

Definition at line 54 of file FS.cpp.

◆ lookup()

llvm::Optional< llvm::vfs::Status > clang::clangd::PreambleFileStatusCache::lookup ( llvm::StringRef  Path) const

Path is a path stored in preamble.

Definition at line 40 of file FS.cpp.

◆ update()

void clang::clangd::PreambleFileStatusCache::update ( const llvm::vfs::FileSystem &  FS,
llvm::vfs::Status  S 
)

Definition at line 25 of file FS.cpp.


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