Add -emit-llvm-only option (generate LLVM IR & run passes, but discard
output).
 - For timing IRgen phase.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@65580 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Driver/Backend.cpp b/Driver/Backend.cpp
index 8cffae0..3c7c1bc 100644
--- a/Driver/Backend.cpp
+++ b/Driver/Backend.cpp
@@ -181,6 +181,9 @@
 }
 
 bool BackendConsumer::AddEmitPasses(std::string &Error) {
+  if (Action == Backend_EmitNothing)
+    return true;
+
   if (OutputFile == "-" || (InputFile == "-" && OutputFile.empty())) {
     AsmOutStream = new raw_stdout_ostream();
     sys::Program::ChangeStdoutToBinary();