diff --git a/clang/lib/CodeGen/CodeGenAction.cpp b/clang/lib/CodeGen/CodeGenAction.cpp
--- a/clang/lib/CodeGen/CodeGenAction.cpp
+++ b/clang/lib/CodeGen/CodeGenAction.cpp
@@ -1113,7 +1113,7 @@
   auto &CodeGenOpts = CI.getCodeGenOpts();
   auto &Diagnostics = CI.getDiagnostics();
   std::unique_ptr<raw_pwrite_stream> OS =
-      GetOutputStream(CI, getCurrentFile(), BA);
+      GetOutputStream(CI, getCurrentFileOrBufferName(), BA);
   if (BA != Backend_EmitNothing && !OS)
     return;
 
diff --git a/clang/unittests/Frontend/CodeGenActionTest.cpp b/clang/unittests/Frontend/CodeGenActionTest.cpp
--- a/clang/unittests/Frontend/CodeGenActionTest.cpp
+++ b/clang/unittests/Frontend/CodeGenActionTest.cpp
@@ -59,4 +59,21 @@
   EXPECT_TRUE(Success);
 }
 
+TEST(CodeGenTest, CodeGenFromIRMemBuffer) {
+  auto Invocation = std::make_shared<CompilerInvocation>();
+  std::unique_ptr<MemoryBuffer> MemBuffer =
+      MemoryBuffer::getMemBuffer("", "test.ll");
+  Invocation->getFrontendOpts().Inputs.push_back(
+      FrontendInputFile(*MemBuffer, Language::LLVM_IR));
+  Invocation->getFrontendOpts().ProgramAction = frontend::EmitLLVMOnly;
+  Invocation->getTargetOpts().Triple = "i386-unknown-linux-gnu";
+  CompilerInstance Compiler;
+  Compiler.setInvocation(std::move(Invocation));
+  Compiler.createDiagnostics();
+  EXPECT_TRUE(Compiler.hasDiagnostics());
+
+  EmitLLVMOnlyAction Action;
+  bool Success = Compiler.ExecuteAction(Action);
+  EXPECT_TRUE(Success);
+}
 }