Improve our uniquing of file entries when files are re-saved or are

overridden via remapping. Thus, when we create a "virtual" file in the
file manager, we still stat() the real file that lives behind it so
that we can provide proper uniquing based on inodes. This helps keep
the file manager much more consistent.

To take advantage of this when reparsing files in libclang, we disable
the use of the stat() cache when reparsing or performing code
completion, since the stat() cache is very likely to be out of date in
this use case.

llvm-svn: 124971

3 files changed, 8 insertions, 2 deletions

diff --git a/clang/lib/Frontend/ASTUnit.cpp b/clang/lib/Frontend/ASTUnit.cpp
index 1db81cb13e8..1138cd7db0d 100644
--- a/clang/lib/Frontend/ASTUnit.cpp
+++ b/clang/lib/Frontend/ASTUnit.cpp
@@ -1580,6 +1580,7 @@ bool ASTUnit::Reparse(RemappedFile *RemappedFiles, unsigned NumRemappedFiles) {
 
   // Remap files.
   PreprocessorOptions &PPOpts = Invocation->getPreprocessorOpts();
+  PPOpts.DisableStatCache = true;
   for (PreprocessorOptions::remapped_file_buffer_iterator 
          R = PPOpts.remapped_file_buffer_begin(),
          REnd = PPOpts.remapped_file_buffer_end();
@@ -1948,6 +1949,7 @@ void ASTUnit::CodeComplete(llvm::StringRef File, unsigned Line, unsigned Column,
 
   // If the main file has been overridden due to the use of a preamble,
   // make that override happen and introduce the preamble.
+  PreprocessorOpts.DisableStatCache = true;
   StoredDiagnostics.insert(StoredDiagnostics.end(),
                            this->StoredDiagnostics.begin(),
              this->StoredDiagnostics.begin() + NumStoredDiagnosticsFromDriver);
diff --git a/clang/lib/Frontend/CompilerInstance.cpp b/clang/lib/Frontend/CompilerInstance.cpp
index 92aed39b5c3..412e7111e48 100644
--- a/clang/lib/Frontend/CompilerInstance.cpp
+++ b/clang/lib/Frontend/CompilerInstance.cpp
@@ -234,11 +234,13 @@ void CompilerInstance::createASTContext() {
 
 void CompilerInstance::createPCHExternalASTSource(llvm::StringRef Path,
                                                   bool DisablePCHValidation,
+                                                  bool DisableStatCache,
                                                  void *DeserializationListener){
   llvm::OwningPtr<ExternalASTSource> Source;
   bool Preamble = getPreprocessorOpts().PrecompiledPreambleBytes.first != 0;
   Source.reset(createPCHExternalASTSource(Path, getHeaderSearchOpts().Sysroot,
-                                          DisablePCHValidation,
+                                          DisablePCHValidation, 
+                                          DisableStatCache,
                                           getPreprocessor(), getASTContext(),
                                           DeserializationListener,
                                           Preamble));
@@ -249,6 +251,7 @@ ExternalASTSource *
 CompilerInstance::createPCHExternalASTSource(llvm::StringRef Path,
                                              const std::string &Sysroot,
                                              bool DisablePCHValidation,
+                                             bool DisableStatCache,
                                              Preprocessor &PP,
                                              ASTContext &Context,
                                              void *DeserializationListener,
@@ -256,7 +259,7 @@ CompilerInstance::createPCHExternalASTSource(llvm::StringRef Path,
   llvm::OwningPtr<ASTReader> Reader;
   Reader.reset(new ASTReader(PP, &Context,
                              Sysroot.empty() ? 0 : Sysroot.c_str(),
-                             DisablePCHValidation));
+                             DisablePCHValidation, DisableStatCache));
 
   Reader->setDeserializationListener(
             static_cast<ASTDeserializationListener *>(DeserializationListener));
diff --git a/clang/lib/Frontend/FrontendAction.cpp b/clang/lib/Frontend/FrontendAction.cpp
index 5f78fb17723..af23923002d 100644
--- a/clang/lib/Frontend/FrontendAction.cpp
+++ b/clang/lib/Frontend/FrontendAction.cpp
@@ -224,6 +224,7 @@ bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
       CI.createPCHExternalASTSource(
                                 CI.getPreprocessorOpts().ImplicitPCHInclude,
                                 CI.getPreprocessorOpts().DisablePCHValidation,
+                                CI.getPreprocessorOpts().DisableStatCache,
                                 DeserialListener);
       if (!CI.getASTContext().getExternalSource())
         goto failure;