--- old/src/hotspot/cpu/x86/gc/z/z_x86_64.ad	2019-02-19 14:23:31.601707936 +0100
+++ new/src/hotspot/cpu/x86/gc/z/z_x86_64.ad	2019-02-19 14:23:31.048690118 +0100
@@ -26,9 +26,8 @@
 #include "gc/z/zBarrierSetAssembler.hpp"
 
 static void z_load_barrier_slow_reg(MacroAssembler& _masm, Register dst, Address src, bool weak) {
-  assert(dst != r12, "Invalid register");
-  assert(dst != r15, "Invalid register");
   assert(dst != rsp, "Invalid register");
+  assert(dst != r15, "Invalid register");
 
   const address stub = weak ? ZBarrierSet::assembler()->load_barrier_weak_slow_stub(dst)
                             : ZBarrierSet::assembler()->load_barrier_slow_stub(dst);