src/hotspot/cpu/x86/continuationHelper_x86.inline.hpp

@@ -48,10 +48,13 @@
      sp[-1] = (intptr_t)StubRoutines::cont_preempt_stub();
    } else {
      // The target will check for preemption once it returns to the interpreter
      // or the native wrapper code and will manually jump to the preempt stub.
      JavaThread *thread = JavaThread::current();
+     DEBUG_ONLY(Method* m = f.is_interpreted_frame() ? f.interpreter_frame_method() : f.cb()->as_nmethod()->method();)
+     assert(m->is_object_wait0() || thread->interp_at_preemptable_vmcall_cnt() > 0,
+            "preemptable VM call not using call_VM_preemptable");
      thread->set_preempt_alternate_return(StubRoutines::cont_preempt_stub());
    }
  }
  
  inline int ContinuationHelper::frame_align_words(int size) {