Index: include/llvm/IR/Intrinsics.td
===================================================================
--- include/llvm/IR/Intrinsics.td
+++ include/llvm/IR/Intrinsics.td
@@ -43,6 +43,10 @@
 // reads from and (possibly volatile) writes to memory, it has no side effects.
 def IntrArgMemOnly : IntrinsicProperty;
 
+// IntrInaccessibleMemOnly -- This intrinsic only accesses memory that is not
+// accessible by the module being compiled. This is a weaker form of IntrNoMem.
+def IntrInaccessibleMemOnly : IntrinsicProperty;
+
 // Commutative - This intrinsic is commutative: X op Y == Y op X.
 def Commutative : IntrinsicProperty;
 
Index: utils/TableGen/CodeGenIntrinsics.h
===================================================================
--- utils/TableGen/CodeGenIntrinsics.h
+++ utils/TableGen/CodeGenIntrinsics.h
@@ -62,15 +62,23 @@
   /// accesses that may be performed by the intrinsics. Analogous to
   /// \c FunctionModRefBehaviour.
   enum ModRefBits {
+    /// The intrinsic may access memory that is otherwise inaccessible via
+    /// LLVM IR.
+    MR_InaccessibleMem = 1,
+
+    /// The intrinsic may access memory through pointer arguments.
+    /// LLVM IR.
+    MR_ArgMem = 2,
+
     /// The intrinsic may access memory anywhere, i.e. it is not restricted
     /// to access through pointer arguments.
-    MR_Anywhere = 1,
+    MR_Anywhere = 4 | MR_ArgMem | MR_InaccessibleMem,
 
     /// The intrinsic may read memory.
-    MR_Ref = 2,
+    MR_Ref = 8,
 
     /// The intrinsic may write memory.
-    MR_Mod = 4,
+    MR_Mod = 16,
 
     /// The intrinsic may both read and write memory.
     MR_ModRef = MR_Ref | MR_Mod,
@@ -80,11 +88,14 @@
   /// properties (IntrReadMem, IntrArgMemOnly, etc.).
   enum ModRefBehavior {
     NoMem = 0,
-    ReadArgMem = MR_Ref,
+    ReadArgMem = MR_Ref | MR_ArgMem,
+    ReadInaccessibleMem = MR_Ref | MR_InaccessibleMem,
     ReadMem = MR_Ref | MR_Anywhere,
-    WriteArgMem = MR_Mod,
+    WriteArgMem = MR_Mod | MR_ArgMem,
+    WriteInaccessibleMem = MR_Mod | MR_InaccessibleMem,
     WriteMem = MR_Mod | MR_Anywhere,
-    ReadWriteArgMem = MR_ModRef,
+    ReadWriteArgMem = MR_ModRef | MR_ArgMem,
+    ReadWriteInaccessibleMem = MR_ModRef | MR_InaccessibleMem,
     ReadWriteMem = MR_ModRef | MR_Anywhere,
   };
   ModRefBehavior ModRef;
Index: utils/TableGen/CodeGenTarget.cpp
===================================================================
--- utils/TableGen/CodeGenTarget.cpp
+++ utils/TableGen/CodeGenTarget.cpp
@@ -583,7 +583,9 @@
     else if (Property->getName() == "IntrWriteMem")
       ModRef = ModRefBehavior(ModRef & ~MR_Ref);
     else if (Property->getName() == "IntrArgMemOnly")
-      ModRef = ModRefBehavior(ModRef & ~MR_Anywhere);
+      ModRef = ModRefBehavior((ModRef & ~MR_Anywhere) | MR_ArgMem);
+    else if (Property->getName() == "IntrInaccessibleMemOnly")
+      ModRef = ModRefBehavior((ModRef & ~MR_Anywhere) | MR_InaccessibleMem);
     else if (Property->getName() == "Commutative")
       isCommutative = true;
     else if (Property->getName() == "Throws")
Index: utils/TableGen/IntrinsicEmitter.cpp
===================================================================
--- utils/TableGen/IntrinsicEmitter.cpp
+++ utils/TableGen/IntrinsicEmitter.cpp
@@ -646,6 +646,12 @@
           OS << ",";
         OS << "Attribute::ReadOnly";
         break;
+      case CodeGenIntrinsic::ReadInaccessibleMem:
+        if (addComma)
+          OS << ",";
+        OS << "Attribute::ReadOnly,";
+        OS << "Attribute::InaccessibleMemOnly";
+        break;
       case CodeGenIntrinsic::WriteArgMem:
         if (addComma)
           OS << ",";
@@ -657,11 +663,22 @@
           OS << ",";
         OS << "Attribute::WriteOnly";
         break;
+      case CodeGenIntrinsic::WriteInaccessibleMem:
+        if (addComma)
+          OS << ",";
+        OS << "Attribute::WriteOnly,";
+        OS << "Attribute::InaccessibleMemOnly";
+        break;
       case CodeGenIntrinsic::ReadWriteArgMem:
         if (addComma)
           OS << ",";
         OS << "Attribute::ArgMemOnly";
         break;
+      case CodeGenIntrinsic::ReadWriteInaccessibleMem:
+        if (addComma)
+          OS << ",";
+        OS << "Attribute::InaccessibleMemOnly";
+        break;
       case CodeGenIntrinsic::ReadWriteMem:
         break;
       }