--- old/src/hotspot/share/c1/c1_Runtime1.cpp	2019-01-15 22:00:25.177162785 -0800
+++ new/src/hotspot/share/c1/c1_Runtime1.cpp	2019-01-15 22:00:24.989155875 -0800
@@ -127,6 +127,7 @@
 int Runtime1::_throw_null_pointer_exception_count = 0;
 int Runtime1::_throw_class_cast_exception_count = 0;
 int Runtime1::_throw_incompatible_class_change_error_count = 0;
+int Runtime1::_throw_illegal_monitor_state_exception_count = 0;
 int Runtime1::_throw_array_store_exception_count = 0;
 int Runtime1::_throw_count = 0;
 
@@ -696,6 +697,13 @@
 JRT_END
 
 
+JRT_ENTRY(void, Runtime1::throw_illegal_monitor_state_exception(JavaThread* thread))
+  NOT_PRODUCT(_throw_illegal_monitor_state_exception_count++;)
+  ResourceMark rm(thread);
+  SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_IllegalMonitorStateException());
+JRT_END
+
+
 JRT_ENTRY_NO_ASYNC(void, Runtime1::monitorenter(JavaThread* thread, oopDesc* obj, BasicObjectLock* lock))
   NOT_PRODUCT(_monitorenter_slowcase_cnt++;)
   if (PrintBiasedLockingStatistics) {
@@ -1502,6 +1510,7 @@
   tty->print_cr(" _throw_null_pointer_exception_count:           %d:", _throw_null_pointer_exception_count);
   tty->print_cr(" _throw_class_cast_exception_count:             %d:", _throw_class_cast_exception_count);
   tty->print_cr(" _throw_incompatible_class_change_error_count:  %d:", _throw_incompatible_class_change_error_count);
+  tty->print_cr(" _throw_illegal_monitor_state_exception_count:  %d:", _throw_illegal_monitor_state_exception_count);
   tty->print_cr(" _throw_array_store_exception_count:            %d:", _throw_array_store_exception_count);
   tty->print_cr(" _throw_count:                                  %d:", _throw_count);