Lift VFS from clang to llvm (NFC)

This patch moves the virtual file system form clang to llvm so it can be
used by more projects.

Concretely the patch:
 - Moves VirtualFileSystem.{h|cpp} from clang/Basic to llvm/Support.
 - Moves the corresponding unit test from clang to llvm.
 - Moves the vfs namespace from clang::vfs to llvm::vfs.
 - Formats the lines affected by this change, mostly this is the result of
   the added llvm namespace.

RFC on the mailing list:
http://lists.llvm.org/pipermail/llvm-dev/2018-October/126657.html

Differential revision: https://reviews.llvm.org/D52783

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@344140 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 6 deletions

diff --git a/lib/Frontend/CompilerInstance.cpp b/lib/Frontend/CompilerInstance.cpp
index 05ba3c0265..bba1ef1f4f 100644
--- a/lib/Frontend/CompilerInstance.cpp
+++ b/lib/Frontend/CompilerInstance.cpp
@@ -177,9 +177,9 @@ static void collectIncludePCH(CompilerInstance &CI,
   std::error_code EC;
   SmallString<128> DirNative;
   llvm::sys::path::native(PCHDir->getName(), DirNative);
-  vfs::FileSystem &FS = *FileMgr.getVirtualFileSystem();
+  llvm::vfs::FileSystem &FS = *FileMgr.getVirtualFileSystem();
   SimpleASTReaderListener Validator(CI.getPreprocessor());
-  for (vfs::directory_iterator Dir = FS.dir_begin(DirNative, EC), DirEnd;
+  for (llvm::vfs::directory_iterator Dir = FS.dir_begin(DirNative, EC), DirEnd;
        Dir != DirEnd && !EC; Dir.increment(EC)) {
     // Check whether this is an AST file. ASTReader::isAcceptableASTFile is not
     // used here since we're not interested in validating the PCH at this time,
@@ -198,14 +198,14 @@ static void collectVFSEntries(CompilerInstance &CI,
     return;
 
   // Collect all VFS found.
-  SmallVector<vfs::YAMLVFSEntry, 16> VFSEntries;
+  SmallVector<llvm::vfs::YAMLVFSEntry, 16> VFSEntries;
   for (const std::string &VFSFile : CI.getHeaderSearchOpts().VFSOverlayFiles) {
     llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> Buffer =
         llvm::MemoryBuffer::getFile(VFSFile);
     if (!Buffer)
       return;
-    vfs::collectVFSFromYAML(std::move(Buffer.get()), /*DiagHandler*/ nullptr,
-                            VFSFile, VFSEntries);
+    llvm::vfs::collectVFSFromYAML(std::move(Buffer.get()),
+                                  /*DiagHandler*/ nullptr, VFSFile, VFSEntries);
   }
 
   for (auto &E : VFSEntries)
@@ -303,7 +303,7 @@ CompilerInstance::createDiagnostics(DiagnosticOptions *Opts,
 
 FileManager *CompilerInstance::createFileManager() {
   if (!hasVirtualFileSystem()) {
-    IntrusiveRefCntPtr<vfs::FileSystem> VFS =
+    IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS =
         createVFSFromCompilerInvocation(getInvocation(), getDiagnostics());
     setVirtualFileSystem(VFS);
   }