--- a/src/hotspot/cpu/x86/gc/shared/barrierSetAssembler_x86.cpp	Tue May 14 12:00:49 2019 +0200
+++ b/src/hotspot/cpu/x86/gc/shared/barrierSetAssembler_x86.cpp	Tue May 14 12:07:24 2019 +0200
@@ -30,6 +30,7 @@
 #include "interpreter/interp_masm.hpp"
 #include "memory/universe.hpp"
 #include "runtime/jniHandles.hpp"
+#include "runtime/sharedRuntime.hpp"
 #include "runtime/thread.hpp"
 
 #define __ masm->
@@ -344,3 +345,33 @@
   __ bind(continuation);
 #endif
 }
+
+void BarrierSetAssembler::c2i_entry_barrier(MacroAssembler* masm) {
+  BarrierSetNMethod* bs = BarrierSet::barrier_set()->barrier_set_nmethod();
+  if (bs == NULL) {
+    return;
+  }
+
+  Label bad_call;
+  __ cmpptr(rbx, 0); // rbx contains the incoming method for c2i adapters.
+  __ jcc(Assembler::equal, bad_call);
+
+  // Pointer chase to the method holder to find out if the method is concurrently unloading.
+  Label method_live;
+  __ load_method_holder_cld(rscratch1, rbx);
+
+  // Is it a strong CLD?
+  __ movl(rscratch2, Address(rscratch1, ClassLoaderData::keep_alive_offset()));
+  __ cmpptr(rscratch2, 0);
+  __ jcc(Assembler::greater, method_live);
+
+  // Is it a weak but alive CLD?
+  __ movptr(rscratch1, Address(rscratch1, ClassLoaderData::holder_offset()));
+  __ resolve_weak_handle(rscratch1, rscratch2);
+  __ cmpptr(rscratch1, 0);
+  __ jcc(Assembler::notEqual, method_live);
+
+  __ bind(bad_call);
+  __ jump(RuntimeAddress(SharedRuntime::get_handle_wrong_method_stub()));
+  __ bind(method_live);
+}