diff --git a/llvm/include/llvm/IR/IntrinsicsX86.td b/llvm/include/llvm/IR/IntrinsicsX86.td
--- a/llvm/include/llvm/IR/IntrinsicsX86.td
+++ b/llvm/include/llvm/IR/IntrinsicsX86.td
@@ -277,9 +277,9 @@
 // Control register.
 let TargetPrefix = "x86" in {  // All intrinsics start with "llvm.x86.".
   def int_x86_sse_stmxcsr :
-              Intrinsic<[], [llvm_ptr_ty], []>;
+              Intrinsic<[], [llvm_ptr_ty], [IntrWriteMem]>;
   def int_x86_sse_ldmxcsr :
-              Intrinsic<[], [llvm_ptr_ty], []>;
+              Intrinsic<[], [llvm_ptr_ty], [IntrReadMem, IntrHasSideEffects]>;
 }
 
 // Misc.