diff -r b5b3db42efca -r d109bda16490 src/cpu/x86/vm/c1_LIRGenerator_x86.cpp
--- a/src/cpu/x86/vm/c1_LIRGenerator_x86.cpp	Tue Mar 29 23:01:10 2016 +0100
+++ b/src/cpu/x86/vm/c1_LIRGenerator_x86.cpp	Tue Apr 05 08:55:39 2016 -0700
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2005, 2016, 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
@@ -283,7 +283,7 @@
     length.load_item();
 
   }
-  if (needs_store_check) {
+  if (needs_store_check || x->check_boolean()) {
     value.load_item();
   } else {
     value.load_for_store(x->elt_type());
@@ -331,7 +331,8 @@
     // Seems to be a precise
     post_barrier(LIR_OprFact::address(array_addr), value.result());
   } else {
-    __ move(value.result(), array_addr, null_check_info);
+    LIR_Opr result = maybe_mask_boolean(x, array.result(), value.result(), null_check_info);
+    __ move(result, array_addr, null_check_info);
   }
 }