1 files changed, 11 insertions, 3 deletions
diff --git a/llvm/utils/TableGen/CodeGenTarget.cpp b/llvm/utils/TableGen/CodeGenTarget.cpp
index 61b9fa8..0e93635 100644
--- a/llvm/utils/TableGen/CodeGenTarget.cpp
+++ b/llvm/utils/TableGen/CodeGenTarget.cpp
@@ -821,11 +821,19 @@ void CodeGenIntrinsic::setDefaultProperties(
 void CodeGenIntrinsic::setProperty(Record *R) {
   if (R->getName() == "IntrNoMem")
     ModRef = NoMem;
-  else if (R->getName() == "IntrReadMem")
+  else if (R->getName() == "IntrReadMem") {
+    if (!(ModRef & MR_Ref))
+      PrintFatalError(TheDef->getLoc(),
+                      Twine("IntrReadMem cannot be used after IntrNoMem or "
+                            "IntrWriteMem. Default is ReadWrite"));
     ModRef = ModRefBehavior(ModRef & ~MR_Mod);
-  else if (R->getName() == "IntrWriteMem")
+  } else if (R->getName() == "IntrWriteMem") {
+    if (!(ModRef & MR_Mod))
+      PrintFatalError(TheDef->getLoc(),
+                      Twine("IntrWriteMem cannot be used after IntrNoMem or "
+                            "IntrReadMem. Default is ReadWrite"));
     ModRef = ModRefBehavior(ModRef & ~MR_Ref);
-  else if (R->getName() == "IntrArgMemOnly")
+  } else if (R->getName() == "IntrArgMemOnly")
     ModRef = ModRefBehavior((ModRef & ~MR_Anywhere) | MR_ArgMem);
   else if (R->getName() == "IntrInaccessibleMemOnly")
     ModRef = ModRefBehavior((ModRef & ~MR_Anywhere) | MR_InaccessibleMem);