From ff04b3d4d72fdad7b3fd9f02e2be155ee5e2f058 Mon Sep 17 00:00:00 2001
From: Jonas Devlieghere <jonas@devlieghere.com>
Date: Thu, 14 Feb 2019 18:05:43 +0000
Subject: [PATCH] [ExpressionParser] Reuse the FileManager from the compiler
 instance.

I was looking at the ClangExpressionParser and noticed that we have a
FileManager owned by the expression parser and later ask the compiler
instance to create a new FileManager, owned by the clang CI. Looking at
the code I don't see a good reason for having two instances. This patch
removes the one owned by LLDB.

Differential revision: https://reviews.llvm.org/D58222

llvm-svn: 354041
---
 .../Clang/ClangExpressionParser.cpp              | 16 +++++-----------
 .../Clang/ClangExpressionParser.h                |  2 --
 2 files changed, 5 insertions(+), 13 deletions(-)

diff --git a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp
index acb08a698e12..937d6c70d3ae 100644
--- a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp
+++ b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp
@@ -11,7 +11,6 @@
 #include "clang/AST/ExternalASTSource.h"
 #include "clang/AST/PrettyPrinter.h"
 #include "clang/Basic/DiagnosticIDs.h"
-#include "clang/Basic/FileManager.h"
 #include "clang/Basic/SourceLocation.h"
 #include "clang/Basic/TargetInfo.h"
 #include "clang/Basic/Version.h"
@@ -490,14 +489,9 @@ ClangExpressionParser::ClangExpressionParser(ExecutionContextScope *exe_scope,
   m_compiler->getDiagnostics().setClient(new ClangDiagnosticManagerAdapter);
 
   // 7. Set up the source management objects inside the compiler
-
-  clang::FileSystemOptions file_system_options;
-  m_file_manager.reset(new clang::FileManager(file_system_options));
-
-  if (!m_compiler->hasSourceManager())
-    m_compiler->createSourceManager(*m_file_manager);
-
   m_compiler->createFileManager();
+  if (!m_compiler->hasSourceManager())
+    m_compiler->createSourceManager(m_compiler->getFileManager());
   m_compiler->createPreprocessor(TU_Complete);
 
   if (ClangModulesDeclVendor *decl_vendor =
@@ -855,9 +849,9 @@ ClangExpressionParser::ParseInternal(DiagnosticManager &diagnostic_manager,
       if (file.Write(expr_text, bytes_written).Success()) {
         if (bytes_written == expr_text_len) {
           file.Close();
-          source_mgr.setMainFileID(
-              source_mgr.createFileID(m_file_manager->getFile(result_path),
-                                      SourceLocation(), SrcMgr::C_User));
+          source_mgr.setMainFileID(source_mgr.createFileID(
+              m_compiler->getFileManager().getFile(result_path),
+              SourceLocation(), SrcMgr::C_User));
           created_main_file = true;
         }
       }
diff --git a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.h b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.h
index 8dfff842646f..e950a6943063 100644
--- a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.h
+++ b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.h
@@ -178,8 +178,6 @@ private:
 
   std::unique_ptr<llvm::LLVMContext>
       m_llvm_context; ///< The LLVM context to generate IR into
-  std::unique_ptr<clang::FileManager>
-      m_file_manager; ///< The Clang file manager object used by the compiler
   std::unique_ptr<clang::CompilerInstance>
       m_compiler; ///< The Clang compiler used to parse expressions into IR
   std::unique_ptr<clang::CodeGenerator>