--- a/hotspot/src/cpu/x86/vm/macroAssembler_x86.cpp	Thu Jun 22 15:26:34 2017 -0700
+++ b/hotspot/src/cpu/x86/vm/macroAssembler_x86.cpp	Thu Jun 22 20:47:22 2017 -0400
@@ -32,6 +32,7 @@
 #include "memory/resourceArea.hpp"
 #include "memory/universe.hpp"
 #include "oops/klass.inline.hpp"
+#include "prims/jvm.h"
 #include "prims/methodHandles.hpp"
 #include "runtime/biasedLocking.hpp"
 #include "runtime/interfaceSupport.hpp"
@@ -3640,6 +3641,12 @@
   call(RuntimeAddress(CAST_FROM_FN_PTR(address, os::breakpoint)));
 }
 
+void MacroAssembler::unimplemented(const char* what) {
+  char* b = new char[1024];
+  jio_snprintf(b, 1024, "unimplemented: %s", what);
+  stop(b);
+}
+
 #ifdef _LP64
 #define XSTATE_BV 0x200
 #endif