diff --git a/clang/include/clang/Basic/SourceManager.h b/clang/include/clang/Basic/SourceManager.h
--- a/clang/include/clang/Basic/SourceManager.h
+++ b/clang/include/clang/Basic/SourceManager.h
@@ -997,8 +997,11 @@
     return nullptr;
   }
 
-  /// Returns the FileEntryRef for the provided FileID.
-  Optional<FileEntryRef> getFileEntryRefForID(FileID FID) const;
+  /// Returns the filename for the provided FileID, unless it's a built-in
+  /// buffer that's not represented by a filename.
+  ///
+  /// Returns None for non-files and built-in files.
+  Optional<StringRef> getNonBuiltinFilenameForID(FileID FID) const;
 
   /// Returns the FileEntry record for the provided SLocEntry.
   const FileEntry *getFileEntryForSLocEntry(const SrcMgr::SLocEntry &sloc) const
diff --git a/clang/lib/Basic/SourceManager.cpp b/clang/lib/Basic/SourceManager.cpp
--- a/clang/lib/Basic/SourceManager.cpp
+++ b/clang/lib/Basic/SourceManager.cpp
@@ -725,11 +725,12 @@
   const_cast<SrcMgr::ContentCache *>(CC)->IsTransient = true;
 }
 
-Optional<FileEntryRef> SourceManager::getFileEntryRefForID(FileID FID) const {
+Optional<StringRef>
+SourceManager::getNonBuiltinFilenameForID(FileID FID) const {
   if (const SrcMgr::SLocEntry *Entry = getSLocEntryForFile(FID))
     if (auto *Content = Entry->getFile().getContentCache())
       if (Content && Content->OrigEntry)
-        return FileEntryRef(Entry->getFile().getName(), *Content->OrigEntry);
+        return Entry->getFile().getName();
   return None;
 }
 
diff --git a/clang/lib/Frontend/DependencyFile.cpp b/clang/lib/Frontend/DependencyFile.cpp
--- a/clang/lib/Frontend/DependencyFile.cpp
+++ b/clang/lib/Frontend/DependencyFile.cpp
@@ -46,17 +46,12 @@
     // Dependency generation really does want to go all the way to the
     // file entry for a source location to find out what is depended on.
     // We do not want #line markers to affect dependency generation!
-    Optional<FileEntryRef> File =
-        SM.getFileEntryRefForID(SM.getFileID(SM.getExpansionLoc(Loc)));
-    if (!File)
-      return;
-
-    StringRef Filename =
-        llvm::sys::path::remove_leading_dotslash(File->getName());
-
-    DepCollector.maybeAddDependency(Filename, /*FromModule*/false,
-                                    isSystem(FileType),
-                                    /*IsModuleFile*/false, /*IsMissing*/false);
+    if (Optional<StringRef> Filename = SM.getNonBuiltinFilenameForID(
+            SM.getFileID(SM.getExpansionLoc(Loc))))
+      DepCollector.maybeAddDependency(
+          llvm::sys::path::remove_leading_dotslash(*Filename),
+          /*FromModule*/ false, isSystem(FileType), /*IsModuleFile*/ false,
+          /*IsMissing*/ false);
   }
 
   void FileSkipped(const FileEntryRef &SkippedFile, const Token &FilenameTok,
diff --git a/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp b/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp
--- a/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp
+++ b/clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp
@@ -77,15 +77,10 @@
   // Dependency generation really does want to go all the way to the
   // file entry for a source location to find out what is depended on.
   // We do not want #line markers to affect dependency generation!
-  Optional<FileEntryRef> File =
-      SM.getFileEntryRefForID(SM.getFileID(SM.getExpansionLoc(Loc)));
-  if (!File)
-    return;
-
-  StringRef FileName =
-      llvm::sys::path::remove_leading_dotslash(File->getName());
-
-  MDC.MainDeps.push_back(std::string(FileName));
+  if (Optional<StringRef> Filename =
+          SM.getNonBuiltinFilenameForID(SM.getFileID(SM.getExpansionLoc(Loc))))
+    MDC.MainDeps.push_back(
+        std::string(llvm::sys::path::remove_leading_dotslash(*Filename)));
 }
 
 void ModuleDepCollectorPP::InclusionDirective(