--- old/src/hotspot/cpu/x86/macroAssembler_x86.hpp	2018-03-21 12:02:51.036047143 +0100
+++ new/src/hotspot/cpu/x86/macroAssembler_x86.hpp	2018-03-21 12:02:50.772041228 +0100
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2018, 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
@@ -97,11 +97,17 @@
   void null_check(Register reg, int offset = -1);
   static bool needs_explicit_null_check(intptr_t offset);
 
+  void test_klass_is_value(Register klass, Register temp_reg, Label& is_value);
+
   void test_field_is_flattenable(Register flags, Register temp_reg, Label& is_flattenable);
   void test_field_is_not_flattenable(Register flags, Register temp_reg, Label& notFlattenable);
   void test_field_is_flattened(Register flags, Register temp_reg, Label& is_flattened);
   void test_value_is_not_buffered(Register value, Register temp_reg, Label& not_buffered);
 
+  // Check klass/oops is flat value type array (oop->_klass->_layout_helper & vt_bit)
+  void test_flat_array_klass(Register klass, Register temp_reg, Label& is_flat_array);
+  void test_flat_array_oop(Register oop, Register temp_reg, Label& is_flat_array);
+
   // Required platform-specific helpers for Label::patch_instructions.
   // They _shadow_ the declarations in AbstractAssembler, which are undefined.
   void pd_patch_instruction(address branch, address target) {