diff --git a/clang/include/clang/Lex/HeaderSearch.h b/clang/include/clang/Lex/HeaderSearch.h
index e88e600ba2b974..b523ad5ef9ff23 100644
--- a/clang/include/clang/Lex/HeaderSearch.h
+++ b/clang/include/clang/Lex/HeaderSearch.h
@@ -20,6 +20,7 @@
 #include "clang/Lex/ModuleMap.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/ADT/StringSet.h"
@@ -314,6 +315,9 @@ class HeaderSearch {
   /// whether they were valid or not.
   llvm::DenseMap<const FileEntry *, bool> LoadedModuleMaps;
 
+  // A map of discovered headers with their associated include file name.
+  llvm::DenseMap<const FileEntry *, llvm::SmallString<64>> IncludeNames;
+
   /// Uniqued set of framework names, which is used to track which
   /// headers were included as framework headers.
   llvm::StringSet<llvm::BumpPtrAllocator> FrameworkNames;
@@ -823,6 +827,13 @@ class HeaderSearch {
   /// Retrieve a uniqued framework name.
   StringRef getUniqueFrameworkName(StringRef Framework);
 
+  /// Retrieve the include name for the header.
+  ///
+  /// \param File The entry for a given header.
+  /// \returns The name of how the file was included when the header's location
+  /// was resolved.
+  StringRef getIncludeNameForHeader(const FileEntry *File) const;
+
   /// Suggest a path by which the specified file could be found, for use in
   /// diagnostics to suggest a #include. Returned path will only contain forward
   /// slashes as separators. MainFile is the absolute path of the file that we
diff --git a/clang/lib/Lex/HeaderSearch.cpp b/clang/lib/Lex/HeaderSearch.cpp
index 14b9a1d7f68be1..5fd853541b6a21 100644
--- a/clang/lib/Lex/HeaderSearch.cpp
+++ b/clang/lib/Lex/HeaderSearch.cpp
@@ -1030,8 +1030,11 @@ Optional<FileEntryRef> HeaderSearch::LookupFile(
 
     CurDir = It;
 
+    const auto FE = &File->getFileEntry();
+    IncludeNames[FE] = Filename;
+
     // This file is a system header or C++ unfriendly if the dir is.
-    HeaderFileInfo &HFI = getFileInfo(&File->getFileEntry());
+    HeaderFileInfo &HFI = getFileInfo(FE);
     HFI.DirInfo = CurDir->getDirCharacteristic();
 
     // If the directory characteristic is User but this framework was
@@ -1460,6 +1463,13 @@ StringRef HeaderSearch::getUniqueFrameworkName(StringRef Framework) {
   return FrameworkNames.insert(Framework).first->first();
 }
 
+StringRef HeaderSearch::getIncludeNameForHeader(const FileEntry *File) const {
+  auto It = IncludeNames.find(File);
+  if (It == IncludeNames.end())
+    return {};
+  return It->second;
+}
+
 bool HeaderSearch::hasModuleMap(StringRef FileName,
                                 const DirectoryEntry *Root,
                                 bool IsSystem) {
diff --git a/clang/unittests/Lex/HeaderSearchTest.cpp b/clang/unittests/Lex/HeaderSearchTest.cpp
index fbb5cb30754a79..87d1c01650987b 100644
--- a/clang/unittests/Lex/HeaderSearchTest.cpp
+++ b/clang/unittests/Lex/HeaderSearchTest.cpp
@@ -207,6 +207,7 @@ TEST_F(HeaderSearchTest, HeaderFrameworkLookup) {
   EXPECT_TRUE(FI);
   EXPECT_TRUE(FI->IsValid);
   EXPECT_EQ(FI->Framework.str(), "Foo");
+  EXPECT_EQ(Search.getIncludeNameForHeader(FE), "Foo/Foo.h");
 }
 
 // Helper struct with null terminator character to make MemoryBuffer happy.
@@ -275,6 +276,7 @@ TEST_F(HeaderSearchTest, HeaderMapFrameworkLookup) {
   EXPECT_TRUE(FI);
   EXPECT_TRUE(FI->IsValid);
   EXPECT_EQ(FI->Framework.str(), "Foo");
+  EXPECT_EQ(Search.getIncludeNameForHeader(FE), "Foo/Foo.h");
 }
 
 } // namespace