rework the stat cache, pulling it out of FileManager.h into
its own header and giving it some more structure. No
functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@120030 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Basic/CMakeLists.txt b/lib/Basic/CMakeLists.txt
index f7dd8c1..12bc7d4 100644
--- a/lib/Basic/CMakeLists.txt
+++ b/lib/Basic/CMakeLists.txt
@@ -6,6 +6,7 @@
Diagnostic.cpp
DiagnosticIDs.cpp
FileManager.cpp
+ FileSystemStatCache.cpp
IdentifierTable.cpp
SourceLocation.cpp
SourceManager.cpp
diff --git a/lib/Basic/FileManager.cpp b/lib/Basic/FileManager.cpp
index 9066359..9572aaad 100644
--- a/lib/Basic/FileManager.cpp
+++ b/lib/Basic/FileManager.cpp
@@ -1,4 +1,4 @@
-///===--- FileManager.cpp - File System Probing and Caching ----------------===//
+//===--- FileManager.cpp - File System Probing and Caching ----------------===//
//
// The LLVM Compiler Infrastructure
//
@@ -18,7 +18,7 @@
//===----------------------------------------------------------------------===//
#include "clang/Basic/FileManager.h"
-#include "clang/Basic/FileSystemOptions.h"
+#include "clang/Basic/FileSystemStatCache.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Support/MemoryBuffer.h"
@@ -162,7 +162,8 @@
delete *V;
}
-void FileManager::addStatCache(StatSysCallCache *statCache, bool AtBeginning) {
+void FileManager::addStatCache(FileSystemStatCache *statCache,
+ bool AtBeginning) {
assert(statCache && "No stat cache provided?");
if (AtBeginning || StatCache.get() == 0) {
statCache->setNextStatCache(StatCache.take());
@@ -170,14 +171,14 @@
return;
}
- StatSysCallCache *LastCache = StatCache.get();
+ FileSystemStatCache *LastCache = StatCache.get();
while (LastCache->getNextStatCache())
LastCache = LastCache->getNextStatCache();
LastCache->setNextStatCache(statCache);
}
-void FileManager::removeStatCache(StatSysCallCache *statCache) {
+void FileManager::removeStatCache(FileSystemStatCache *statCache) {
if (!statCache)
return;
@@ -188,7 +189,7 @@
}
// Find the stat cache in the list.
- StatSysCallCache *PrevCache = StatCache.get();
+ FileSystemStatCache *PrevCache = StatCache.get();
while (PrevCache && PrevCache->getNextStatCache() != statCache)
PrevCache = PrevCache->getNextStatCache();
if (PrevCache)
@@ -249,8 +250,8 @@
// Check to see if the directory exists.
struct stat StatBuf;
- if (stat_cached(InterndDirName, &StatBuf) || // Error stat'ing.
- !S_ISDIR(StatBuf.st_mode)) // Not a directory?
+ if (getStatValue(InterndDirName, StatBuf) || // Error stat'ing.
+ !S_ISDIR(StatBuf.st_mode)) // Not a directory?
return 0;
// It exists. See if we have already opened a directory with the same inode.
@@ -306,8 +307,8 @@
// Nope, there isn't. Check to see if the file exists.
struct stat StatBuf;
//llvm::errs() << "STATING: " << Filename;
- if (stat_cached(InterndFileName, &StatBuf) || // Error stat'ing.
- S_ISDIR(StatBuf.st_mode)) { // A directory?
+ if (getStatValue(InterndFileName, StatBuf) || // Error stat'ing.
+ S_ISDIR(StatBuf.st_mode)) { // A directory?
// If this file doesn't exist, we leave a null in FileEntries for this path.
//llvm::errs() << ": Not existing\n";
return 0;
@@ -370,7 +371,7 @@
// newly-created file entry.
const char *InterndFileName = NamedFileEnt.getKeyData();
struct stat StatBuf;
- if (!stat_cached(InterndFileName, &StatBuf) &&
+ if (!getStatValue(InterndFileName, StatBuf) &&
!S_ISDIR(StatBuf.st_mode)) {
llvm::sys::Path FilePath(InterndFileName);
FilePath.makeAbsolute();
@@ -410,17 +411,36 @@
return llvm::MemoryBuffer::getFile(FilePath.c_str(), ErrorStr);
}
-int FileManager::stat_cached(const char *path, struct stat *buf) {
- if (FileSystemOpts.WorkingDir.empty())
- return StatCache.get() ? StatCache->stat(path, buf) : stat(path, buf);
-
- llvm::sys::Path FilePath(path);
+/// getStatValue - Get the 'stat' information for the specified path, using the
+/// cache to accellerate it if possible. This returns true if the path does not
+/// exist or false if it exists.
+bool FileManager::getStatValue(const char *Path, struct stat &StatBuf) {
+ FileSystemStatCache::LookupResult Result = FileSystemStatCache::CacheMiss;
+
+ // FIXME: FileSystemOpts shouldn't be passed in here, all paths should be
+ // absolute!
+ if (FileSystemOpts.WorkingDir.empty()) {
+ if (StatCache.get())
+ Result = StatCache->getStat(Path, StatBuf);
+
+ if (Result == FileSystemStatCache::CacheMiss)
+ return ::stat(Path, &StatBuf);
+ return Result == FileSystemStatCache::CacheHitMissing;
+ }
+
+ llvm::sys::Path FilePath(Path);
FixupRelativePath(FilePath, FileSystemOpts);
-
- return StatCache.get() ? StatCache->stat(FilePath.c_str(), buf)
- : stat(FilePath.c_str(), buf);
+
+ if (StatCache.get())
+ Result = StatCache->getStat(FilePath.c_str(), StatBuf);
+
+ if (Result == FileSystemStatCache::CacheMiss)
+ return ::stat(FilePath.c_str(), &StatBuf);
+ return Result == FileSystemStatCache::CacheHitMissing;
}
+
+
void FileManager::PrintStats() const {
llvm::errs() << "\n*** File Manager Stats:\n";
llvm::errs() << UniqueFiles.size() << " files found, "
@@ -433,19 +453,3 @@
//llvm::errs() << PagesMapped << BytesOfPagesMapped << FSLookups;
}
-int MemorizeStatCalls::stat(const char *path, struct stat *buf) {
- int result = StatSysCallCache::stat(path, buf);
-
- // Do not cache failed stats, it is easy to construct common inconsistent
- // situations if we do, and they are not important for PCH performance (which
- // currently only needs the stats to construct the initial FileManager
- // entries).
- if (result != 0)
- return result;
-
- // Cache file 'stat' results and directories with absolutely paths.
- if (!S_ISDIR(buf->st_mode) || llvm::sys::Path(path).isAbsolute())
- StatCalls[path] = StatResult(result, *buf);
-
- return result;
-}
diff --git a/lib/Basic/FileSystemStatCache.cpp b/lib/Basic/FileSystemStatCache.cpp
new file mode 100644
index 0000000..8fd31d5
--- /dev/null
+++ b/lib/Basic/FileSystemStatCache.cpp
@@ -0,0 +1,40 @@
+//===--- FileSystemStatCache.cpp - Caching for 'stat' calls ---------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines the FileSystemStatCache interface.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Basic/FileSystemStatCache.h"
+#include "llvm/System/Path.h"
+using namespace clang;
+
+MemorizeStatCalls::LookupResult
+MemorizeStatCalls::getStat(const char *Path, struct stat &StatBuf) {
+ LookupResult Result = statChained(Path, StatBuf);
+
+ // If the chained cache didn't know anything about the file, do the stat now
+ // so we can record the result.
+ if (Result == CacheMiss)
+ Result = ::stat(Path, &StatBuf) ? CacheHitMissing : CacheHitExists;
+
+
+ // Do not cache failed stats, it is easy to construct common inconsistent
+ // situations if we do, and they are not important for PCH performance (which
+ // currently only needs the stats to construct the initial FileManager
+ // entries).
+ if (Result == CacheHitMissing)
+ return Result;
+
+ // Cache file 'stat' results and directories with absolutely paths.
+ if (!S_ISDIR(StatBuf.st_mode) || llvm::sys::Path(Path).isAbsolute())
+ StatCalls[Path] = StatResult(Result, StatBuf);
+
+ return Result;
+}