Make getModRefInfo(Instruction *) not crash on certain types of instructions

llvm-svn: 236023
diff --git a/llvm/unittests/Analysis/AliasAnalysisTest.cpp b/llvm/unittests/Analysis/AliasAnalysisTest.cpp
index 1ba396c..66ed463 100644
--- a/llvm/unittests/Analysis/AliasAnalysisTest.cpp
+++ b/llvm/unittests/Analysis/AliasAnalysisTest.cpp
@@ -81,6 +81,13 @@
   auto *Store1 = new StoreInst(Value, Addr, BB);
   auto *Load1 = new LoadInst(Addr, "load", BB);
   auto *Add1 = BinaryOperator::CreateAdd(Value, Value, "add", BB);
+  auto *VAArg1 = new VAArgInst(Addr, PtrType, "vaarg", BB);
+  auto *CmpXChg1 = new AtomicCmpXchgInst(Addr, ConstantInt::get(IntType, 0),
+                                         ConstantInt::get(IntType, 1),
+                                         Monotonic, Monotonic, CrossThread, BB);
+  auto *AtomicRMW =
+      new AtomicRMWInst(AtomicRMWInst::Xchg, Addr, ConstantInt::get(IntType, 1),
+                        Monotonic, CrossThread, BB);
 
   ReturnInst::Create(C, nullptr, BB);
 
@@ -88,6 +95,9 @@
   CheckModRef(Store1, AliasAnalysis::ModRefResult::Mod);
   CheckModRef(Load1, AliasAnalysis::ModRefResult::Ref);
   CheckModRef(Add1, AliasAnalysis::ModRefResult::NoModRef);
+  CheckModRef(VAArg1, AliasAnalysis::ModRefResult::ModRef);
+  CheckModRef(CmpXChg1, AliasAnalysis::ModRefResult::ModRef);
+  CheckModRef(AtomicRMW, AliasAnalysis::ModRefResult::ModRef);
 }
 
 } // end anonymous namspace