diff --git a/clang/include/clang/Frontend/CompilerInstance.h b/clang/include/clang/Frontend/CompilerInstance.h
--- a/clang/include/clang/Frontend/CompilerInstance.h
+++ b/clang/include/clang/Frontend/CompilerInstance.h
@@ -791,6 +791,12 @@
                                                  SourceLocation ModuleNameLoc,
                                                  bool IsInclusionDirective);
 
+  // Get the submodule corresponding to the module path.
+  Module *getSubmoduleCorrespondingToPath(
+    bool &MapPrivateSubModToTopLevel, Module *Module, SourceLocation ImportLoc,
+    ModuleIdPath Path, Module::NameVisibilityKind Visibility,
+    bool IsInclusionDirective);
+
 public:
   ModuleLoadResult loadModule(SourceLocation ImportLoc, ModuleIdPath Path,
                               Module::NameVisibilityKind Visibility,
diff --git a/clang/lib/Frontend/CompilerInstance.cpp b/clang/lib/Frontend/CompilerInstance.cpp
--- a/clang/lib/Frontend/CompilerInstance.cpp
+++ b/clang/lib/Frontend/CompilerInstance.cpp
@@ -1931,65 +1931,12 @@
   return M;
 }
 
-ModuleLoadResult
-CompilerInstance::loadModule(SourceLocation ImportLoc,
-                             ModuleIdPath Path,
-                             Module::NameVisibilityKind Visibility,
-                             bool IsInclusionDirective) {
-  // Determine what file we're searching from.
-  StringRef ModuleName = Path[0].first->getName();
-  SourceLocation ModuleNameLoc = Path[0].second;
-
-  // If we've already handled this import, just return the cached result.
-  // This one-element cache is important to eliminate redundant diagnostics
-  // when both the preprocessor and parser see the same import declaration.
-  if (ImportLoc.isValid() && LastModuleImportLoc == ImportLoc) {
-    // Make the named module visible.
-    if (LastModuleImportResult && ModuleName != getLangOpts().CurrentModule)
-      TheASTReader->makeModuleVisible(LastModuleImportResult, Visibility,
-                                      ImportLoc);
-    return LastModuleImportResult;
-  }
-
-  // If we don't already have information on this module, load the module now.
-  Module *Module = nullptr;
-  ModuleMap &MM = getPreprocessor().getHeaderSearchInfo().getModuleMap();
-  if (auto MaybeModule = MM.getCachedModuleLoad(*Path[0].first)) {
-    // Use the cached result, which may be nullptr.
-    Module = *MaybeModule;
-  } else if (ModuleName == getLangOpts().CurrentModule) {
-    // This is the module we're building.
-    Module = PP->getHeaderSearchInfo().lookupModule(
-        ModuleName, ImportLoc, /*AllowSearch*/ true,
-        /*AllowExtraModuleMapSearch*/ !IsInclusionDirective);
-    /// FIXME: perhaps we should (a) look for a module using the module name
-    //  to file map (PrebuiltModuleFiles) and (b) diagnose if still not found?
-    //if (Module == nullptr) {
-    //  getDiagnostics().Report(ModuleNameLoc, diag::err_module_not_found)
-    //    << ModuleName;
-    //  DisableGeneratingGlobalModuleIndex = true;
-    //  return ModuleLoadResult();
-    //}
-    MM.cacheModuleLoad(*Path[0].first, Module);
-  } else {
-    ModuleLoadResult Result = findOrCompileModuleAndReadAST(
-        ModuleName, ImportLoc, ModuleNameLoc, IsInclusionDirective);
-    if (!Result.isNormal())
-      return Result;
-    if (!Result)
-      DisableGeneratingGlobalModuleIndex = true;
-    Module = Result;
-    MM.cacheModuleLoad(*Path[0].first, Module);
-  }
-
-  // If we never found the module, fail.  Otherwise, verify the module and link
-  // it up.
-  if (!Module)
-    return ModuleLoadResult();
+Module *CompilerInstance::getSubmoduleCorrespondingToPath(
+    bool &MapPrivateSubModToTopLevel, Module *Module, SourceLocation ImportLoc,
+    ModuleIdPath Path, Module::NameVisibilityKind Visibility,
+    bool IsInclusionDirective) {
+  MapPrivateSubModToTopLevel = false;
 
-  // Verify that the rest of the module path actually corresponds to
-  // a submodule.
-  bool MapPrivateSubModToTopLevel = false;
   for (unsigned I = 1, N = Path.size(); I != N; ++I) {
     StringRef Name = Path[I].first->getName();
     clang::Module *Sub = Module->findSubmodule(Name);
@@ -2070,6 +2017,70 @@
     Module = Sub;
   }
 
+  return Module;
+}
+
+ModuleLoadResult
+CompilerInstance::loadModule(SourceLocation ImportLoc,
+                             ModuleIdPath Path,
+                             Module::NameVisibilityKind Visibility,
+                             bool IsInclusionDirective) {
+  // Determine what file we're searching from.
+  StringRef ModuleName = Path[0].first->getName();
+  SourceLocation ModuleNameLoc = Path[0].second;
+
+  // If we've already handled this import, just return the cached result.
+  // This one-element cache is important to eliminate redundant diagnostics
+  // when both the preprocessor and parser see the same import declaration.
+  if (ImportLoc.isValid() && LastModuleImportLoc == ImportLoc) {
+    // Make the named module visible.
+    if (LastModuleImportResult && ModuleName != getLangOpts().CurrentModule)
+      TheASTReader->makeModuleVisible(LastModuleImportResult, Visibility,
+                                      ImportLoc);
+    return LastModuleImportResult;
+  }
+
+  // If we don't already have information on this module, load the module now.
+  Module *Module = nullptr;
+  ModuleMap &MM = getPreprocessor().getHeaderSearchInfo().getModuleMap();
+  if (auto MaybeModule = MM.getCachedModuleLoad(*Path[0].first)) {
+    // Use the cached result, which may be nullptr.
+    Module = *MaybeModule;
+  } else if (ModuleName == getLangOpts().CurrentModule) {
+    // This is the module we're building.
+    Module = PP->getHeaderSearchInfo().lookupModule(
+        ModuleName, ImportLoc, /*AllowSearch*/ true,
+        /*AllowExtraModuleMapSearch*/ !IsInclusionDirective);
+    /// FIXME: perhaps we should (a) look for a module using the module name
+    //  to file map (PrebuiltModuleFiles) and (b) diagnose if still not found?
+    //if (Module == nullptr) {
+    //  getDiagnostics().Report(ModuleNameLoc, diag::err_module_not_found)
+    //    << ModuleName;
+    //  DisableGeneratingGlobalModuleIndex = true;
+    //  return ModuleLoadResult();
+    //}
+    MM.cacheModuleLoad(*Path[0].first, Module);
+  } else {
+    ModuleLoadResult Result = findOrCompileModuleAndReadAST(
+        ModuleName, ImportLoc, ModuleNameLoc, IsInclusionDirective);
+    if (!Result.isNormal())
+      return Result;
+    if (!Result)
+      DisableGeneratingGlobalModuleIndex = true;
+    Module = Result;
+    MM.cacheModuleLoad(*Path[0].first, Module);
+  }
+
+  // If we never found the module, fail.  Otherwise, verify the module and link
+  // it up.
+  if (!Module)
+    return ModuleLoadResult();
+
+  bool MapPrivateSubModToTopLevel = false;
+  Module = getSubmoduleCorrespondingToPath(MapPrivateSubModToTopLevel, Module,
+                                           ImportLoc, Path, Visibility,
+                                           IsInclusionDirective);
+
   // Make the named module visible, if it's not already part of the module
   // we are parsing.
   if (ModuleName != getLangOpts().CurrentModule) {