Revert "Reapply [VFS] Add 'overlay-relative' field to YAML files"

Tests failing on
http://bb.pgr.jp/builders/cmake-clang-x86_64-linux/builds/46102

This reverts commit a1683cd6c9e07359c09f86e98a4db6b4e1bc51fc.

llvm-svn: 263750

1 files changed, 18 insertions, 95 deletions

diff --git a/clang/lib/Basic/VirtualFileSystem.cpp b/clang/lib/Basic/VirtualFileSystem.cpp
index 83400cf..e1c4d71 100644
--- a/clang/lib/Basic/VirtualFileSystem.cpp
+++ b/clang/lib/Basic/VirtualFileSystem.cpp
@@ -780,7 +780,6 @@ public:
 /// All configuration options are optional.
 ///   'case-sensitive': <boolean, default=true>
 ///   'use-external-names': <boolean, default=true>
-///   'overlay-relative': <boolean, default=false>
 ///
 /// Virtual directories are represented as
 /// \verbatim
@@ -820,10 +819,6 @@ class RedirectingFileSystem : public vfs::FileSystem {
   std::vector<std::unique_ptr<Entry>> Roots;
   /// \brief The file system to use for external references.
   IntrusiveRefCntPtr<FileSystem> ExternalFS;
-  /// If IsRelativeOverlay is set, this represents the directory
-  /// path that should be prefixed to each 'external-contents' entry
-  /// when reading from YAML files.
-  std::string ExternalContentsPrefixDir;
 
   /// @name Configuration
   /// @{
@@ -833,10 +828,6 @@ class RedirectingFileSystem : public vfs::FileSystem {
   /// Currently, case-insensitive matching only works correctly with ASCII.
   bool CaseSensitive;
 
-  /// IsRelativeOverlay marks whether a IsExternalContentsPrefixDir path must
-  /// be prefixed in every 'external-contents' when reading from YAML files.
-  bool IsRelativeOverlay = false;
-
   /// \brief Whether to use to use the value of 'external-contents' for the
   /// names of files.  This global value is overridable on a per-file basis.
   bool UseExternalNames;
@@ -874,8 +865,8 @@ public:
   /// returns a virtual file system representing its contents.
   static RedirectingFileSystem *
   create(std::unique_ptr<MemoryBuffer> Buffer,
-         SourceMgr::DiagHandlerTy DiagHandler, StringRef YAMLFilePath,
-         void *DiagContext, IntrusiveRefCntPtr<FileSystem> ExternalFS);
+         SourceMgr::DiagHandlerTy DiagHandler, void *DiagContext,
+         IntrusiveRefCntPtr<FileSystem> ExternalFS);
 
   ErrorOr<Status> status(const Twine &Path) override;
   ErrorOr<std::unique_ptr<File>> openFileForRead(const Twine &Path) override;
@@ -908,15 +899,6 @@ public:
     return directory_iterator(std::make_shared<VFSFromYamlDirIterImpl>(Dir,
         *this, D->contents_begin(), D->contents_end(), EC));
   }
-
-  void setExternalContentsPrefixDir(StringRef PrefixDir) {
-    ExternalContentsPrefixDir = PrefixDir.str();
-  }
-
-  StringRef getExternalContentsPrefixDir() const {
-    return ExternalContentsPrefixDir;
-  }
-
 };
 
 /// \brief A helper class to hold the common YAML parsing state.
@@ -1090,24 +1072,16 @@ class RedirectingFileSystemParser {
         HasContents = true;
         if (!parseScalarString(I->getValue(), Value, Buffer))
           return nullptr;
-
-        SmallString<256> FullPath;
-        if (FS->IsRelativeOverlay) {
-          FullPath = FS->getExternalContentsPrefixDir();
-          assert(!FullPath.empty() &&
-                 "External contents prefix directory must exist");
-          llvm::sys::path::append(FullPath, Value);
-        } else {
-          FullPath = Value;
-        }
-
         if (FS->UseCanonicalizedPaths) {
+          SmallString<256> Path(Value);
           // Guarantee that old YAML files containing paths with ".." and "."
           // are properly canonicalized before read into the VFS.
-          FullPath = sys::path::remove_leading_dotslash(FullPath);
-          sys::path::remove_dots(FullPath, /*remove_dot_dot=*/true);
+          Path = sys::path::remove_leading_dotslash(Path);
+          sys::path::remove_dots(Path, /*remove_dot_dot=*/true);
+          ExternalContentsPath = Path.str();
+        } else {
+          ExternalContentsPath = Value;
         }
-        ExternalContentsPath = FullPath.str();
       } else if (Key == "use-external-name") {
         bool Val;
         if (!parseScalarBool(I->getValue(), Val))
@@ -1193,7 +1167,6 @@ public:
       KeyStatusPair("version", true),
       KeyStatusPair("case-sensitive", false),
       KeyStatusPair("use-external-names", false),
-      KeyStatusPair("overlay-relative", false),
       KeyStatusPair("roots", true),
     };
 
@@ -1245,9 +1218,6 @@ public:
       } else if (Key == "case-sensitive") {
         if (!parseScalarBool(I->getValue(), FS->CaseSensitive))
           return false;
-      } else if (Key == "overlay-relative") {
-        if (!parseScalarBool(I->getValue(), FS->IsRelativeOverlay))
-          return false;
       } else if (Key == "use-external-names") {
         if (!parseScalarBool(I->getValue(), FS->UseExternalNames))
           return false;
@@ -1268,11 +1238,9 @@ public:
 
 Entry::~Entry() = default;
 
-RedirectingFileSystem *
-RedirectingFileSystem::create(std::unique_ptr<MemoryBuffer> Buffer,
-                              SourceMgr::DiagHandlerTy DiagHandler,
-                              StringRef YAMLFilePath, void *DiagContext,
-                              IntrusiveRefCntPtr<FileSystem> ExternalFS) {
+RedirectingFileSystem *RedirectingFileSystem::create(
+    std::unique_ptr<MemoryBuffer> Buffer, SourceMgr::DiagHandlerTy DiagHandler,
+    void *DiagContext, IntrusiveRefCntPtr<FileSystem> ExternalFS) {
 
   SourceMgr SM;
   yaml::Stream Stream(Buffer->getMemBufferRef(), SM);
@@ -1289,23 +1257,6 @@ RedirectingFileSystem::create(std::unique_ptr<MemoryBuffer> Buffer,
 
   std::unique_ptr<RedirectingFileSystem> FS(
       new RedirectingFileSystem(ExternalFS));
-
-  if (!YAMLFilePath.empty()) {
-    // Use the YAML path from -ivfsoverlay to compute the dir to be prefixed
-    // to each 'external-contents' path.
-    //
-    // Example:
-    //    -ivfsoverlay dummy.cache/vfs/vfs.yaml
-    // yields:
-    //  FS->ExternalContentsPrefixDir => /<absolute_path_to>/dummy.cache/vfs
-    //
-    SmallString<256> OverlayAbsDir = sys::path::parent_path(YAMLFilePath);
-    std::error_code EC = llvm::sys::fs::make_absolute(OverlayAbsDir);
-    assert(!EC && "Overlay dir final path must be absolute");
-    (void)EC;
-    FS->setExternalContentsPrefixDir(OverlayAbsDir);
-  }
-
   if (!P.parse(Root, FS.get()))
     return nullptr;
 
@@ -1459,12 +1410,10 @@ RedirectingFileSystem::openFileForRead(const Twine &Path) {
 
 IntrusiveRefCntPtr<FileSystem>
 vfs::getVFSFromYAML(std::unique_ptr<MemoryBuffer> Buffer,
-                    SourceMgr::DiagHandlerTy DiagHandler,
-                    StringRef YAMLFilePath,
-                    void *DiagContext,
+                    SourceMgr::DiagHandlerTy DiagHandler, void *DiagContext,
                     IntrusiveRefCntPtr<FileSystem> ExternalFS) {
   return RedirectingFileSystem::create(std::move(Buffer), DiagHandler,
-                                       YAMLFilePath, DiagContext, ExternalFS);
+                                       DiagContext, ExternalFS);
 }
 
 UniqueID vfs::getNextVirtualUniqueID() {
@@ -1496,8 +1445,7 @@ class JSONWriter {
 
 public:
   JSONWriter(llvm::raw_ostream &OS) : OS(OS) {}
-  void write(ArrayRef<YAMLVFSEntry> Entries, Optional<bool> IsCaseSensitive,
-             Optional<bool> IsOverlayRelative, StringRef OverlayDir);
+  void write(ArrayRef<YAMLVFSEntry> Entries, Optional<bool> IsCaseSensitive);
 };
 }
 
@@ -1550,9 +1498,7 @@ void JSONWriter::writeEntry(StringRef VPath, StringRef RPath) {
 }
 
 void JSONWriter::write(ArrayRef<YAMLVFSEntry> Entries,
-                       Optional<bool> IsCaseSensitive,
-                       Optional<bool> IsOverlayRelative,
-                       StringRef OverlayDir) {
+                       Optional<bool> IsCaseSensitive) {
   using namespace llvm::sys;
 
   OS << "{\n"
@@ -1560,27 +1506,12 @@ void JSONWriter::write(ArrayRef<YAMLVFSEntry> Entries,
   if (IsCaseSensitive.hasValue())
     OS << "  'case-sensitive': '"
        << (IsCaseSensitive.getValue() ? "true" : "false") << "',\n";
-  bool UseOverlayRelative = false;
-  if (IsOverlayRelative.hasValue()) {
-    UseOverlayRelative = IsOverlayRelative.getValue();
-    OS << "  'overlay-relative': '"
-       << (UseOverlayRelative ? "true" : "false") << "',\n";
-  }
   OS << "  'roots': [\n";
 
   if (!Entries.empty()) {
     const YAMLVFSEntry &Entry = Entries.front();
     startDirectory(path::parent_path(Entry.VPath));
-
-    StringRef RPath = Entry.RPath;
-    if (UseOverlayRelative) {
-      unsigned OverlayDirLen = OverlayDir.size();
-      assert(RPath.substr(0, OverlayDirLen) == OverlayDir &&
-             "Overlay dir must be contained in RPath");
-      RPath = RPath.slice(OverlayDirLen, RPath.size());
-    }
-
-    writeEntry(path::filename(Entry.VPath), RPath);
+    writeEntry(path::filename(Entry.VPath), Entry.RPath);
 
     for (const auto &Entry : Entries.slice(1)) {
       StringRef Dir = path::parent_path(Entry.VPath);
@@ -1594,14 +1525,7 @@ void JSONWriter::write(ArrayRef<YAMLVFSEntry> Entries,
         OS << ",\n";
         startDirectory(Dir);
       }
-      StringRef RPath = Entry.RPath;
-      if (UseOverlayRelative) {
-        unsigned OverlayDirLen = OverlayDir.size();
-        assert(RPath.substr(0, OverlayDirLen) == OverlayDir &&
-               "Overlay dir must be contained in RPath");
-        RPath = RPath.slice(OverlayDirLen, RPath.size());
-      }
-      writeEntry(path::filename(Entry.VPath), RPath);
+      writeEntry(path::filename(Entry.VPath), Entry.RPath);
     }
 
     while (!DirStack.empty()) {
@@ -1621,8 +1545,7 @@ void YAMLVFSWriter::write(llvm::raw_ostream &OS) {
     return LHS.VPath < RHS.VPath;
   });
 
-  JSONWriter(OS).write(Mappings, IsCaseSensitive, IsOverlayRelative,
-                       OverlayDir);
+  JSONWriter(OS).write(Mappings, IsCaseSensitive);
 }
 
 VFSFromYamlDirIterImpl::VFSFromYamlDirIterImpl(