diff --git a/include/clang/Frontend/ASTUnit.h b/include/clang/Frontend/ASTUnit.h
index b1cdb46..03961f1 100644
--- a/include/clang/Frontend/ASTUnit.h
+++ b/include/clang/Frontend/ASTUnit.h
@@ -519,6 +519,8 @@
 
   const FileSystemOptions &getFileSystemOpts() const { return FileSystemOpts; }
 
+  IntrusiveRefCntPtr<ASTReader> getASTReader() const;
+
   StringRef getOriginalSourceFileName() {
     return OriginalSourceFile;
   }
diff --git a/include/clang/Index/IndexingAction.h b/include/clang/Index/IndexingAction.h
index e2e63dc..8eed33c 100644
--- a/include/clang/Index/IndexingAction.h
+++ b/include/clang/Index/IndexingAction.h
@@ -14,9 +14,14 @@
 #include <memory>
 
 namespace clang {
+  class ASTReader;
   class ASTUnit;
   class FrontendAction;
 
+namespace serialization {
+  class ModuleFile;
+}
+
 namespace index {
   class IndexDataConsumer;
 
@@ -42,6 +47,11 @@
                   std::shared_ptr<IndexDataConsumer> DataConsumer,
                   IndexingOptions Opts);
 
+void indexModuleFile(serialization::ModuleFile &Mod,
+                     ASTReader &Reader,
+                     std::shared_ptr<IndexDataConsumer> DataConsumer,
+                     IndexingOptions Opts);
+
 } // namespace index
 } // namespace clang
 
diff --git a/include/clang/Serialization/ASTReader.h b/include/clang/Serialization/ASTReader.h
index 93994e2..3282eb0 100644
--- a/include/clang/Serialization/ASTReader.h
+++ b/include/clang/Serialization/ASTReader.h
@@ -1268,6 +1268,7 @@
   llvm::iterator_range<PreprocessingRecord::iterator>
   getModulePreprocessedEntities(ModuleFile &Mod) const;
 
+public:
   class ModuleDeclIterator
       : public llvm::iterator_adaptor_base<
             ModuleDeclIterator, const serialization::LocalDeclID *,
@@ -1298,6 +1299,7 @@
   llvm::iterator_range<ModuleDeclIterator>
   getModuleFileLevelDecls(ModuleFile &Mod);
 
+private:
   void PassInterestingDeclsToConsumer();
   void PassInterestingDeclToConsumer(Decl *D);
 
@@ -2189,6 +2191,12 @@
   /// \brief Loads comments ranges.
   void ReadComments() override;
 
+  /// Visit all the input files of the given module file.
+  void visitInputFiles(serialization::ModuleFile &MF,
+                       bool IncludeSystem, bool Complain,
+          llvm::function_ref<void(const serialization::InputFile &IF,
+                                  bool isSystem)> Visitor);
+
   bool isProcessingUpdateRecords() { return ProcessingUpdateRecords; }
 };
 
diff --git a/include/clang/Serialization/Module.h b/include/clang/Serialization/Module.h
index 58b3149..f0629ed 100644
--- a/include/clang/Serialization/Module.h
+++ b/include/clang/Serialization/Module.h
@@ -210,6 +210,10 @@
   /// \brief The input files that have been loaded from this AST file.
   std::vector<InputFile> InputFilesLoaded;
 
+  // All user input files reside at the index range [0, NumUserInputFiles), and
+  // system input files reside at [NumUserInputFiles, InputFilesLoaded.size()).
+  unsigned NumUserInputFiles = 0;
+
   /// \brief If non-zero, specifies the time when we last validated input
   /// files.  Zero means we never validated them.
   ///
diff --git a/lib/Frontend/ASTUnit.cpp b/lib/Frontend/ASTUnit.cpp
index d892996..c29b908 100644
--- a/lib/Frontend/ASTUnit.cpp
+++ b/lib/Frontend/ASTUnit.cpp
@@ -619,6 +619,10 @@
     StoredDiags.emplace_back(Level, Info);
 }
 
+IntrusiveRefCntPtr<ASTReader> ASTUnit::getASTReader() const {
+  return Reader;
+}
+
 ASTMutationListener *ASTUnit::getASTMutationListener() {
   if (WriterData)
     return &WriterData->Writer;
diff --git a/lib/Index/CMakeLists.txt b/lib/Index/CMakeLists.txt
index 8f51ccb..c9fbfaf 100644
--- a/lib/Index/CMakeLists.txt
+++ b/lib/Index/CMakeLists.txt
@@ -24,5 +24,6 @@
   clangFormat
   clangFrontend
   clangRewrite
+  clangSerialization
   clangToolingCore
   )
diff --git a/lib/Index/IndexingAction.cpp b/lib/Index/IndexingAction.cpp
index d744293..cac24d4 100644
--- a/lib/Index/IndexingAction.cpp
+++ b/lib/Index/IndexingAction.cpp
@@ -13,6 +13,7 @@
 #include "clang/Frontend/FrontendAction.h"
 #include "clang/Frontend/MultiplexConsumer.h"
 #include "clang/Lex/Preprocessor.h"
+#include "clang/Serialization/ASTReader.h"
 
 using namespace clang;
 using namespace clang::index;
@@ -173,4 +174,20 @@
   IndexCtx.setASTContext(Unit.getASTContext());
   DataConsumer->initialize(Unit.getASTContext());
   indexTranslationUnit(Unit, IndexCtx);
+  DataConsumer->finish();
+}
+
+void index::indexModuleFile(serialization::ModuleFile &Mod,
+                            ASTReader &Reader,
+                            std::shared_ptr<IndexDataConsumer> DataConsumer,
+                            IndexingOptions Opts) {
+  ASTContext &Ctx = Reader.getContext();
+  IndexingContext IndexCtx(Opts, *DataConsumer);
+  IndexCtx.setASTContext(Ctx);
+  DataConsumer->initialize(Ctx);
+
+  for (const Decl *D :Reader.getModuleFileLevelDecls(Mod)) {
+    IndexCtx.indexTopLevelDecl(D);
+  }
+  DataConsumer->finish();
 }
diff --git a/lib/Serialization/ASTReader.cpp b/lib/Serialization/ASTReader.cpp
index da822c3..00db74a 100644
--- a/lib/Serialization/ASTReader.cpp
+++ b/lib/Serialization/ASTReader.cpp
@@ -2513,6 +2513,7 @@
       F.InputFileOffsets =
           (const llvm::support::unaligned_uint64_t *)Blob.data();
       F.InputFilesLoaded.resize(NumInputs);
+      F.NumUserInputFiles = NumUserInputs;
       break;
     }
   }
@@ -8534,6 +8535,21 @@
   }
 }
 
+void ASTReader::visitInputFiles(serialization::ModuleFile &MF,
+                                bool IncludeSystem, bool Complain,
+                    llvm::function_ref<void(const serialization::InputFile &IF,
+                                            bool isSystem)> Visitor) {
+  unsigned NumUserInputs = MF.NumUserInputFiles;
+  unsigned NumInputs = MF.InputFilesLoaded.size();
+  assert(NumUserInputs <= NumInputs);
+  unsigned N = IncludeSystem ? NumInputs : NumUserInputs;
+  for (unsigned I = 0; I < N; ++I) {
+    bool IsSystem = I >= NumUserInputs;
+    InputFile IF = getInputFile(MF, I+1, Complain);
+    Visitor(IF, IsSystem);
+  }
+}
+
 std::string ASTReader::getOwningModuleNameForDiagnostic(const Decl *D) {
   // If we know the owning module, use it.
   if (Module *M = D->getImportedOwningModule())
diff --git a/test/Index/Core/index-pch.c b/test/Index/Core/index-pch.c
new file mode 100644
index 0000000..773cfc5
--- /dev/null
+++ b/test/Index/Core/index-pch.c
@@ -0,0 +1,13 @@
+// RUN: c-index-test core -print-source-symbols -- %s | FileCheck %s
+// RUN: %clang_cc1 -emit-pch %s -o %t.pch
+// RUN: c-index-test core -print-source-symbols -module-file %t.pch | FileCheck %s
+
+// CHECK: [[@LINE+1]]:6 | function/C | test1 | [[TEST1_USR:.*]] | [[TEST1_CG:.*]] | Decl | rel: 0
+void test1();
+
+// CHECK: [[@LINE+1]]:20 | function/C | test2 | [[TEST2_USR:.*]] | {{.*}} | Def | rel: 0
+static inline void test2() {
+  // CHECK: [[@LINE+2]]:3 | function/C | test1 | [[TEST1_USR]] | [[TEST1_CG]] | Ref,Call,RelCall,RelCont | rel: 1
+  // CHECK-NEXT: RelCall,RelCont | test2 | [[TEST2_USR]]
+  test1();
+}
diff --git a/test/Index/Core/index-with-module.m b/test/Index/Core/index-with-module.m
index e50b247..c83de63 100644
--- a/test/Index/Core/index-with-module.m
+++ b/test/Index/Core/index-with-module.m
@@ -1,5 +1,5 @@
 // RUN: rm -rf %t.mcp
-// RUN: c-index-test core -print-source-symbols -- %s -I %S/Inputs/module -fmodules -fmodules-cache-path=%t.mcp | FileCheck %s
+// RUN: c-index-test core -print-source-symbols -dump-imported-module-files -- %s -I %S/Inputs/module -fmodules -fmodules-cache-path=%t.mcp | FileCheck %s
 
 // CHECK: [[@LINE+1]]:9 | module/C | ModA | Decl |
 @import ModA;
@@ -10,3 +10,9 @@
   // CHECK: [[@LINE+1]]:3 | function/C | ModA_func | c:@F@ModA_func | {{.*}} | Ref,Call,RelCall,RelCont | rel: 1
   ModA_func();
 }
+
+// CHECK: ==== Module ModA ====
+// CHECK: 2:6 | function/C | ModA_func | c:@F@ModA_func | {{.*}} | Decl | rel: 0
+// CHECK: ---- Module Inputs ----
+// CHECK: user | {{.*}}ModA.h
+// CHECK: user | {{.*}}module.modulemap
diff --git a/tools/c-index-test/CMakeLists.txt b/tools/c-index-test/CMakeLists.txt
index e0df503..7244e2c 100644
--- a/tools/c-index-test/CMakeLists.txt
+++ b/tools/c-index-test/CMakeLists.txt
@@ -24,8 +24,10 @@
     libclang
     clangAST
     clangBasic
+    clangCodeGen
     clangFrontend
     clangIndex
+    clangSerialization
   )
 endif()
 
diff --git a/tools/c-index-test/core_main.cpp b/tools/c-index-test/core_main.cpp
index 0ab24fb..f371870 100644
--- a/tools/c-index-test/core_main.cpp
+++ b/tools/c-index-test/core_main.cpp
@@ -7,6 +7,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "clang/CodeGen/ObjectFilePCHContainerOperations.h"
 #include "clang/Frontend/ASTUnit.h"
 #include "clang/Frontend/CompilerInstance.h"
 #include "clang/Frontend/CompilerInvocation.h"
@@ -15,6 +16,7 @@
 #include "clang/Index/IndexDataConsumer.h"
 #include "clang/Index/USRGeneration.h"
 #include "clang/Index/CodegenNameGenerator.h"
+#include "clang/Serialization/ASTReader.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Signals.h"
 #include "llvm/Support/raw_ostream.h"
@@ -49,6 +51,17 @@
   "invocation\n"
 );
 
+static cl::opt<bool>
+DumpModuleImports("dump-imported-module-files",
+               cl::desc("Print symbols and input files from imported modules"));
+
+static cl::opt<std::string>
+ModuleFilePath("module-file",
+               cl::desc("Path to module file to print symbols from"));
+static cl::opt<std::string>
+  ModuleFormat("fmodule-format", cl::init("raw"),
+        cl::desc("Container format for clang modules and PCH, 'raw' or 'obj'"));
+
 }
 } // anonymous namespace
 
@@ -134,7 +147,19 @@
 // Print Source Symbols
 //===----------------------------------------------------------------------===//
 
-static bool printSourceSymbols(ArrayRef<const char *> Args) {
+static void dumpModuleFileInputs(serialization::ModuleFile &Mod,
+                                 ASTReader &Reader,
+                                 raw_ostream &OS) {
+  OS << "---- Module Inputs ----\n";
+  Reader.visitInputFiles(Mod, /*IncludeSystem=*/true, /*Complain=*/false,
+                        [&](const serialization::InputFile &IF, bool isSystem) {
+    OS << (isSystem ? "system" : "user") << " | ";
+    OS << IF.getFile()->getName() << '\n';
+  });
+}
+
+static bool printSourceSymbols(ArrayRef<const char *> Args,
+                               bool dumpModuleImports) {
   SmallVector<const char *, 4> ArgsWithProgName;
   ArgsWithProgName.push_back("clang");
   ArgsWithProgName.append(Args.begin(), Args.end());
@@ -144,7 +169,8 @@
   if (!CInvok)
     return true;
 
-  auto DataConsumer = std::make_shared<PrintIndexDataConsumer>(outs());
+  raw_ostream &OS = outs();
+  auto DataConsumer = std::make_shared<PrintIndexDataConsumer>(OS);
   IndexingOptions IndexOpts;
   std::unique_ptr<FrontendAction> IndexAction;
   IndexAction = createIndexingAction(DataConsumer, IndexOpts,
@@ -157,6 +183,50 @@
   if (!Unit)
     return true;
 
+  if (dumpModuleImports) {
+    if (auto Reader = Unit->getASTReader()) {
+      Reader->getModuleManager().visit([&](serialization::ModuleFile &Mod) -> bool {
+        OS << "==== Module " << Mod.ModuleName << " ====\n";
+        indexModuleFile(Mod, *Reader, DataConsumer, IndexOpts);
+        dumpModuleFileInputs(Mod, *Reader, OS);
+        return true; // skip module dependencies.
+      });
+    }
+  }
+
+  return false;
+}
+
+static bool printSourceSymbolsFromModule(StringRef modulePath,
+                                         StringRef format) {
+  FileSystemOptions FileSystemOpts;
+  auto pchContOps = std::make_shared<PCHContainerOperations>();
+  // Register the support for object-file-wrapped Clang modules.
+  pchContOps->registerReader(llvm::make_unique<ObjectFilePCHContainerReader>());
+  auto pchRdr = pchContOps->getReaderOrNull(format);
+  if (!pchRdr) {
+    errs() << "unknown module format: " << format << '\n';
+    return true;
+  }
+
+  IntrusiveRefCntPtr<DiagnosticsEngine> Diags =
+      CompilerInstance::createDiagnostics(new DiagnosticOptions());
+  std::unique_ptr<ASTUnit> AU = ASTUnit::LoadFromASTFile(
+      modulePath, *pchRdr, Diags,
+      FileSystemOpts, /*UseDebugInfo=*/false,
+      /*OnlyLocalDecls=*/true, None,
+      /*CaptureDiagnostics=*/false,
+      /*AllowPCHWithCompilerErrors=*/true,
+      /*UserFilesAreVolatile=*/false);
+  if (!AU) {
+    errs() << "failed to create TU for: " << modulePath << '\n';
+    return true;
+  }
+
+  auto DataConsumer = std::make_shared<PrintIndexDataConsumer>(outs());
+  IndexingOptions IndexOpts;
+  indexASTUnit(*AU, DataConsumer, IndexOpts);
+
   return false;
 }
 
@@ -219,11 +289,15 @@
   }
 
   if (options::Action == ActionType::PrintSourceSymbols) {
+    if (!options::ModuleFilePath.empty()) {
+      return printSourceSymbolsFromModule(options::ModuleFilePath,
+                                          options::ModuleFormat);
+    }
     if (CompArgs.empty()) {
       errs() << "error: missing compiler args; pass '-- <compiler arguments>'\n";
       return 1;
     }
-    return printSourceSymbols(CompArgs);
+    return printSourceSymbols(CompArgs, options::DumpModuleImports);
   }
 
   return 0;