--- a/src/hotspot/share/c1/c1_LIRGenerator.cpp	Tue Mar 12 16:18:31 2019 +0100
+++ b/src/hotspot/share/c1/c1_LIRGenerator.cpp	Tue Mar 12 11:13:39 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2005, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2005, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -1653,7 +1653,7 @@
   decorators |= ACCESS_READ;
   decorators |= ACCESS_WRITE;
   // Atomic operations are SEQ_CST by default
-  decorators |= ((decorators & MO_DECORATOR_MASK) != 0) ? MO_SEQ_CST : 0;
+  decorators |= ((decorators & MO_DECORATOR_MASK) == 0) ? MO_SEQ_CST : 0;
   LIRAccess access(this, decorators, base, offset, type);
   if (access.is_raw()) {
     return _barrier_set->BarrierSetC1::atomic_cmpxchg_at(access, cmp_value, new_value);
@@ -1667,7 +1667,7 @@
   decorators |= ACCESS_READ;
   decorators |= ACCESS_WRITE;
   // Atomic operations are SEQ_CST by default
-  decorators |= ((decorators & MO_DECORATOR_MASK) != 0) ? MO_SEQ_CST : 0;
+  decorators |= ((decorators & MO_DECORATOR_MASK) == 0) ? MO_SEQ_CST : 0;
   LIRAccess access(this, decorators, base, offset, type);
   if (access.is_raw()) {
     return _barrier_set->BarrierSetC1::atomic_xchg_at(access, value);
@@ -1681,7 +1681,7 @@
   decorators |= ACCESS_READ;
   decorators |= ACCESS_WRITE;
   // Atomic operations are SEQ_CST by default
-  decorators |= ((decorators & MO_DECORATOR_MASK) != 0) ? MO_SEQ_CST : 0;
+  decorators |= ((decorators & MO_DECORATOR_MASK) == 0) ? MO_SEQ_CST : 0;
   LIRAccess access(this, decorators, base, offset, type);
   if (access.is_raw()) {
     return _barrier_set->BarrierSetC1::atomic_add_at(access, value);