r352593 - Simplify and modernize this code a little.
Richard Smith via cfe-commits
cfe-commits at lists.llvm.org
Tue Jan 29 18:23:34 PST 2019
Author: rsmith
Date: Tue Jan 29 18:23:34 2019
New Revision: 352593
URL: http://llvm.org/viewvc/llvm-project?rev=352593&view=rev
Log:
Simplify and modernize this code a little.
No functionality change intended.
Modified:
cfe/trunk/lib/Basic/FileManager.cpp
Modified: cfe/trunk/lib/Basic/FileManager.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Basic/FileManager.cpp?rev=352593&r1=352592&r2=352593&view=diff
==============================================================================
--- cfe/trunk/lib/Basic/FileManager.cpp (original)
+++ cfe/trunk/lib/Basic/FileManager.cpp Tue Jan 29 18:23:34 2019
@@ -35,14 +35,6 @@
using namespace clang;
-/// NON_EXISTENT_DIR - A special value distinct from null that is used to
-/// represent a dir name that doesn't exist on the disk.
-#define NON_EXISTENT_DIR reinterpret_cast<DirectoryEntry*>((intptr_t)-1)
-
-/// NON_EXISTENT_FILE - A special value distinct from null that is used to
-/// represent a filename that doesn't exist on the disk.
-#define NON_EXISTENT_FILE reinterpret_cast<FileEntry*>((intptr_t)-1)
-
//===----------------------------------------------------------------------===//
// Common logic.
//===----------------------------------------------------------------------===//
@@ -95,14 +87,13 @@ void FileManager::addAncestorsAsVirtualD
if (DirName.empty())
DirName = ".";
- auto &NamedDirEnt =
- *SeenDirEntries.insert(std::make_pair(DirName, nullptr)).first;
+ auto &NamedDirEnt = *SeenDirEntries.insert({DirName, nullptr}).first;
// When caching a virtual directory, we always cache its ancestors
// at the same time. Therefore, if DirName is already in the cache,
// we don't need to recurse as its ancestors must also already be in
- // the cache.
- if (NamedDirEnt.second && NamedDirEnt.second != NON_EXISTENT_DIR)
+ // the cache (or it's a known non-virtual directory).
+ if (NamedDirEnt.second)
return;
// Add the virtual directory to the cache.
@@ -136,19 +127,17 @@ const DirectoryEntry *FileManager::getDi
#endif
++NumDirLookups;
- auto &NamedDirEnt =
- *SeenDirEntries.insert(std::make_pair(DirName, nullptr)).first;
// See if there was already an entry in the map. Note that the map
// contains both virtual and real directories.
- if (NamedDirEnt.second)
- return NamedDirEnt.second == NON_EXISTENT_DIR ? nullptr
- : NamedDirEnt.second;
+ auto SeenDirInsertResult = SeenDirEntries.insert({DirName, nullptr});
+ if (!SeenDirInsertResult.second)
+ return SeenDirInsertResult.first->second;
+ // We've not seen this before. Fill it in.
++NumDirCacheMisses;
-
- // By default, initialize it to invalid.
- NamedDirEnt.second = NON_EXISTENT_DIR;
+ auto &NamedDirEnt = *SeenDirInsertResult.first;
+ assert(!NamedDirEnt.second && "should be newly-created");
// Get the null-terminated directory name as stored as the key of the
// SeenDirEntries map.
@@ -184,18 +173,14 @@ const FileEntry *FileManager::getFile(St
++NumFileLookups;
// See if there is already an entry in the map.
- auto &NamedFileEnt =
- *SeenFileEntries.insert(std::make_pair(Filename, nullptr)).first;
-
- // See if there is already an entry in the map.
- if (NamedFileEnt.second)
- return NamedFileEnt.second == NON_EXISTENT_FILE ? nullptr
- : NamedFileEnt.second;
+ auto SeenFileInsertResult = SeenFileEntries.insert({Filename, nullptr});
+ if (!SeenFileInsertResult.second)
+ return SeenFileInsertResult.first->second;
+ // We've not seen this before. Fill it in.
++NumFileCacheMisses;
-
- // By default, initialize it to invalid.
- NamedFileEnt.second = NON_EXISTENT_FILE;
+ auto &NamedFileEnt = *SeenFileInsertResult.first;
+ assert(!NamedFileEnt.second && "should be newly-created");
// Get the null-terminated file name as stored as the key of the
// SeenFileEntries map.
@@ -218,7 +203,7 @@ const FileEntry *FileManager::getFile(St
// FIXME: Use the directory info to prune this, before doing the stat syscall.
// FIXME: This will reduce the # syscalls.
- // Nope, there isn't. Check to see if the file exists.
+ // Check to see if the file exists.
std::unique_ptr<llvm::vfs::File> F;
FileData Data;
if (getStatValue(InterndFileName, Data, true, openFile ? &F : nullptr)) {
@@ -240,13 +225,9 @@ const FileEntry *FileManager::getFile(St
// If the name returned by getStatValue is different than Filename, re-intern
// the name.
if (Data.Name != Filename) {
- auto &NamedFileEnt =
- *SeenFileEntries.insert(std::make_pair(Data.Name, nullptr)).first;
- if (!NamedFileEnt.second)
- NamedFileEnt.second = &UFE;
- else
- assert(NamedFileEnt.second == &UFE &&
- "filename from getStatValue() refers to wrong file");
+ auto &NamedFileEnt = *SeenFileEntries.insert({Data.Name, &UFE}).first;
+ assert(NamedFileEnt.second == &UFE &&
+ "filename from getStatValue() refers to wrong file");
InterndFileName = NamedFileEnt.first().data();
}
@@ -295,19 +276,13 @@ FileManager::getVirtualFile(StringRef Fi
time_t ModificationTime) {
++NumFileLookups;
- // See if there is already an entry in the map.
- auto &NamedFileEnt =
- *SeenFileEntries.insert(std::make_pair(Filename, nullptr)).first;
-
- // See if there is already an entry in the map.
- if (NamedFileEnt.second && NamedFileEnt.second != NON_EXISTENT_FILE)
+ // See if there is already an entry in the map for an existing file.
+ auto &NamedFileEnt = *SeenFileEntries.insert({Filename, nullptr}).first;
+ if (NamedFileEnt.second)
return NamedFileEnt.second;
+ // We've not seen this before, or the file is cached as non-existent.
++NumFileCacheMisses;
-
- // By default, initialize it to invalid.
- NamedFileEnt.second = NON_EXISTENT_FILE;
-
addAncestorsAsVirtualDirs(Filename);
FileEntry *UFE = nullptr;
@@ -343,9 +318,7 @@ FileManager::getVirtualFile(StringRef Fi
UFE->IsNamedPipe = Data.IsNamedPipe;
UFE->InPCH = Data.InPCH;
fillRealPathName(UFE, Data.Name);
- }
-
- if (!UFE) {
+ } else {
VirtualFileEntries.push_back(llvm::make_unique<FileEntry>());
UFE = VirtualFileEntries.back().get();
NamedFileEnt.second = UFE;
@@ -479,6 +452,9 @@ void FileManager::invalidateCache(const
// FileEntry invalidation should not block future optimizations in the file
// caches. Possible alternatives are cache truncation (invalidate last N) or
// invalidation of the whole cache.
+ //
+ // FIXME: This is broken. We sometimes have the same FileEntry* shared
+ // betweeen multiple SeenFileEntries, so this can leave dangling pointers.
UniqueRealFiles.erase(Entry->getUniqueID());
}
@@ -491,13 +467,12 @@ void FileManager::GetUniqueIDMapping(
for (llvm::StringMap<FileEntry*, llvm::BumpPtrAllocator>::const_iterator
FE = SeenFileEntries.begin(), FEEnd = SeenFileEntries.end();
FE != FEEnd; ++FE)
- if (FE->getValue() && FE->getValue() != NON_EXISTENT_FILE)
+ if (FE->getValue())
UIDToFiles[FE->getValue()->getUID()] = FE->getValue();
// Map virtual file entries
for (const auto &VFE : VirtualFileEntries)
- if (VFE && VFE.get() != NON_EXISTENT_FILE)
- UIDToFiles[VFE->getUID()] = VFE.get();
+ UIDToFiles[VFE->getUID()] = VFE.get();
}
void FileManager::modifyFileEntry(FileEntry *File,
@@ -519,7 +494,7 @@ StringRef FileManager::getCanonicalName(
if (!FS->getRealPath(Dir->getName(), CanonicalNameBuf))
CanonicalName = StringRef(CanonicalNameBuf).copy(CanonicalNameStorage);
- CanonicalDirNames.insert(std::make_pair(Dir, CanonicalName));
+ CanonicalDirNames.insert({Dir, CanonicalName});
return CanonicalName;
}
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