diff --git a/llvm/lib/CodeGen/ImplicitNullChecks.cpp b/llvm/lib/CodeGen/ImplicitNullChecks.cpp
index 681103141517..75f4eef5dc1c 100644
--- a/llvm/lib/CodeGen/ImplicitNullChecks.cpp
+++ b/llvm/lib/CodeGen/ImplicitNullChecks.cpp
@@ -235,8 +235,11 @@ bool ImplicitNullChecks::canHandle(const MachineInstr *MI) {
   assert(!llvm::any_of(MI->operands(), IsRegMask) &&
          "Calls were filtered out above!");
 
-  auto IsUnordered = [](MachineMemOperand *MMO) { return MMO->isUnordered(); };
-  return llvm::all_of(MI->memoperands(), IsUnordered);
+  // TODO: This should be isUnordered (see D57601) once test cases are written
+  // demonstrating that.
+  auto IsSimple = [](MachineMemOperand *MMO) {
+    return !MMO->isVolatile() && !MMO->isAtomic(); };
+  return llvm::all_of(MI->memoperands(), IsSimple);
 }
 
 ImplicitNullChecks::DependenceResult
diff --git a/llvm/lib/CodeGen/MachineInstr.cpp b/llvm/lib/CodeGen/MachineInstr.cpp
index 4c80b7bfb0b3..0b8e9caa09b7 100644
--- a/llvm/lib/CodeGen/MachineInstr.cpp
+++ b/llvm/lib/CodeGen/MachineInstr.cpp
@@ -1291,8 +1291,10 @@ bool MachineInstr::hasOrderedMemoryRef() const {
     return true;
 
   // Check if any of our memory operands are ordered.
+  // TODO: This should probably be be isUnordered (see D57601), but the callers
+  // need audited and test cases written to be sure.
   return llvm::any_of(memoperands(), [](const MachineMemOperand *MMO) {
-    return !MMO->isUnordered();
+    return MMO->isVolatile() || MMO->isAtomic();
   });
 }