ignore 'invoke @llvm.donothing', but still keep the edge to the continuation BB

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160411 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 42b9099..54d8cb7 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -1833,7 +1833,7 @@
     visitInlineAsm(&I);
   else if (Fn && Fn->isIntrinsic()) {
     assert(Fn->getIntrinsicID() == Intrinsic::donothing);
-    return; // ignore invokes to @llvm.donothing
+    // Ignore invokes to @llvm.donothing: jump directly to the next BB.
   } else
     LowerCallTo(&I, getValue(Callee), false, LandingPad);