Index: lib/CodeGen/BackendUtil.cpp
===================================================================
--- lib/CodeGen/BackendUtil.cpp
+++ lib/CodeGen/BackendUtil.cpp
@@ -902,7 +902,7 @@
 
 static void runThinLTOBackend(ModuleSummaryIndex *CombinedIndex, Module *M,
                               std::unique_ptr<raw_pwrite_stream> OS,
-                              std::string SampleProfile) {
+                              std::string SampleProfile, BackendAction Action) {
   StringMap<std::map<GlobalValue::GUID, GlobalValueSummary *>>
       ModuleToDefinedGVSummaries;
   CombinedIndex->collectDefinedGVSummariesPerModule(ModuleToDefinedGVSummaries);
@@ -954,6 +954,20 @@
   };
   lto::Config Conf;
   Conf.SampleProfile = std::move(SampleProfile);
+  switch (Action) {
+  case Backend_EmitNothing:
+    Conf.IROutputType = lto::Config::EIRT_Nothing;
+    break;
+  case Backend_EmitLL:
+    Conf.IROutputType = lto::Config::EIRT_LL;
+    break;
+  case Backend_EmitBC:
+    Conf.IROutputType = lto::Config::EIRT_BC;
+    break;
+  default:
+    Conf.IROutputType = lto::Config::EIRT_CodeGen;
+    break;
+  }
   if (Error E = thinBackend(
           Conf, 0, AddStream, *M, *CombinedIndex, ImportList,
           ModuleToDefinedGVSummaries[M->getModuleIdentifier()], ModuleMap)) {
@@ -990,7 +1004,7 @@
     bool DoThinLTOBackend = CombinedIndex != nullptr;
     if (DoThinLTOBackend) {
       runThinLTOBackend(CombinedIndex.get(), M, std::move(OS),
-                        CGOpts.SampleProfileFile);
+                        CGOpts.SampleProfileFile, Action);
       return;
     }
   }
Index: test/CodeGen/thinlto-emit-llvm.c
===================================================================
--- /dev/null
+++ test/CodeGen/thinlto-emit-llvm.c
@@ -0,0 +1,10 @@
+// Test to ensure -emit-llvm and -emit-llvm-bc work when invoking the
+// ThinLTO backend path.
+// RUN: %clang -O2 %s -flto=thin -c -o %t.o
+// RUN: llvm-lto -thinlto -o %t %t.o
+// RUN: %clang_cc1 -O2 -x ir %t.o -fthinlto-index=%t.thinlto.bc -emit-llvm -o - | FileCheck %s
+// RUN: %clang_cc1 -O2 -x ir %t.o -fthinlto-index=%t.thinlto.bc -emit-llvm-bc -o - | llvm-dis -o - | FileCheck %s
+
+// CHECK: define void @foo()
+void foo() {
+}