From bc632902dceaab23f9f567fa26caed3c41714b34 Mon Sep 17 00:00:00 2001
From: Benjamin Kramer <benny.kra@googlemail.com>
Date: Tue, 6 Oct 2015 14:45:20 +0000
Subject: [PATCH] [Tooling] Reuse FileManager in ASTUnit.

ASTUnit was creating multiple FileManagers and throwing them away. Reuse
the one from Tooling. No functionality change now but necessary for
VFSifying tooling.

llvm-svn: 249410
---
 clang/include/clang/Frontend/ASTUnit.h |  6 +++---
 clang/lib/Frontend/ASTUnit.cpp         | 22 +++++++++-------------
 clang/lib/Tooling/Tooling.cpp          |  4 ++--
 3 files changed, 14 insertions(+), 18 deletions(-)

diff --git a/clang/include/clang/Frontend/ASTUnit.h b/clang/include/clang/Frontend/ASTUnit.h
index f977bfdd7852..7d9d12103831 100644
--- a/clang/include/clang/Frontend/ASTUnit.h
+++ b/clang/include/clang/Frontend/ASTUnit.h
@@ -805,9 +805,9 @@ public:
   static std::unique_ptr<ASTUnit> LoadFromCompilerInvocation(
       CompilerInvocation *CI,
       std::shared_ptr<PCHContainerOperations> PCHContainerOps,
-      IntrusiveRefCntPtr<DiagnosticsEngine> Diags, bool OnlyLocalDecls = false,
-      bool CaptureDiagnostics = false, bool PrecompilePreamble = false,
-      TranslationUnitKind TUKind = TU_Complete,
+      IntrusiveRefCntPtr<DiagnosticsEngine> Diags, FileManager *FileMgr,
+      bool OnlyLocalDecls = false, bool CaptureDiagnostics = false,
+      bool PrecompilePreamble = false, TranslationUnitKind TUKind = TU_Complete,
       bool CacheCodeCompletionResults = false,
       bool IncludeBriefCommentsInCodeCompletion = false,
       bool UserFilesAreVolatile = false);
diff --git a/clang/lib/Frontend/ASTUnit.cpp b/clang/lib/Frontend/ASTUnit.cpp
index 90161af26caf..bac9c386a6a5 100644
--- a/clang/lib/Frontend/ASTUnit.cpp
+++ b/clang/lib/Frontend/ASTUnit.cpp
@@ -1076,11 +1076,10 @@ bool ASTUnit::Parse(std::shared_ptr<PCHContainerOperations> PCHContainerOps,
   // Configure the various subsystems.
   LangOpts = Clang->getInvocation().LangOpts;
   FileSystemOpts = Clang->getFileSystemOpts();
-  IntrusiveRefCntPtr<vfs::FileSystem> VFS =
-      createVFSFromCompilerInvocation(Clang->getInvocation(), getDiagnostics());
-  if (!VFS)
-    return true;
-  FileMgr = new FileManager(FileSystemOpts, VFS);
+  if (!FileMgr) {
+    Clang->createFileManager();
+    FileMgr = &Clang->getFileManager();
+  }
   SourceMgr = new SourceManager(getDiagnostics(), *FileMgr,
                                 UserFilesAreVolatile);
   TheSema.reset();
@@ -1892,8 +1891,8 @@ bool ASTUnit::LoadFromCompilerInvocation(
 std::unique_ptr<ASTUnit> ASTUnit::LoadFromCompilerInvocation(
     CompilerInvocation *CI,
     std::shared_ptr<PCHContainerOperations> PCHContainerOps,
-    IntrusiveRefCntPtr<DiagnosticsEngine> Diags, bool OnlyLocalDecls,
-    bool CaptureDiagnostics, bool PrecompilePreamble,
+    IntrusiveRefCntPtr<DiagnosticsEngine> Diags, FileManager *FileMgr,
+    bool OnlyLocalDecls, bool CaptureDiagnostics, bool PrecompilePreamble,
     TranslationUnitKind TUKind, bool CacheCodeCompletionResults,
     bool IncludeBriefCommentsInCodeCompletion, bool UserFilesAreVolatile) {
   // Create the AST unit.
@@ -1907,12 +1906,8 @@ std::unique_ptr<ASTUnit> ASTUnit::LoadFromCompilerInvocation(
   AST->IncludeBriefCommentsInCodeCompletion
     = IncludeBriefCommentsInCodeCompletion;
   AST->Invocation = CI;
-  AST->FileSystemOpts = CI->getFileSystemOpts();
-  IntrusiveRefCntPtr<vfs::FileSystem> VFS =
-      createVFSFromCompilerInvocation(*CI, *Diags);
-  if (!VFS)
-    return nullptr;
-  AST->FileMgr = new FileManager(AST->FileSystemOpts, VFS);
+  AST->FileSystemOpts = FileMgr->getFileSystemOpts();
+  AST->FileMgr = FileMgr;
   AST->UserFilesAreVolatile = UserFilesAreVolatile;
   
   // Recover resources if we crash before exiting this method.
@@ -2043,6 +2038,7 @@ bool ASTUnit::Reparse(std::shared_ptr<PCHContainerOperations> PCHContainerOps,
         getMainBufferWithPrecompiledPreamble(PCHContainerOps, *Invocation);
 
   // Clear out the diagnostics state.
+  FileMgr.reset();
   getDiagnostics().Reset();
   ProcessWarningOptions(getDiagnostics(), Invocation->getDiagnosticOpts());
   if (OverrideMainBuffer)
diff --git a/clang/lib/Tooling/Tooling.cpp b/clang/lib/Tooling/Tooling.cpp
index f361d1f4115c..8c7ed78d4149 100644
--- a/clang/lib/Tooling/Tooling.cpp
+++ b/clang/lib/Tooling/Tooling.cpp
@@ -418,12 +418,12 @@ public:
   bool runInvocation(CompilerInvocation *Invocation, FileManager *Files,
                      std::shared_ptr<PCHContainerOperations> PCHContainerOps,
                      DiagnosticConsumer *DiagConsumer) override {
-    // FIXME: This should use the provided FileManager.
     std::unique_ptr<ASTUnit> AST = ASTUnit::LoadFromCompilerInvocation(
         Invocation, PCHContainerOps,
         CompilerInstance::createDiagnostics(&Invocation->getDiagnosticOpts(),
                                             DiagConsumer,
-                                            /*ShouldOwnClient=*/false));
+                                            /*ShouldOwnClient=*/false),
+        Files);
     if (!AST)
       return false;