8235696: ZGC: assert(ZNMethod::is_armed(nm) == _should_disarm_nmethods) failed: Invalid state

Reviewed-by: eosterlund, stefank

src/hotspot/share/gc/shared/barrierSetNMethod.hpp

@@ -32,11 +32,12 @@
 class nmethod;
 
 class BarrierSetNMethod: public CHeapObj<mtGC> {
-  bool supports_entry_barrier(nmethod* nm);
   void deoptimize(nmethod* nm, address* return_addr_ptr);
   int disarmed_value() const;
 
 public:
+  bool supports_entry_barrier(nmethod* nm);
+
   virtual bool nmethod_entry_barrier(nmethod* nm) = 0;
   virtual ByteSize thread_disarmed_offset() const = 0;
   virtual int* disarmed_value_address() const = 0;

src/hotspot/share/gc/z/zNMethod.cpp

@@ -187,6 +187,15 @@ void ZNMethod::flush_nmethod(nmethod* nm) {
   delete gc_data(nm);
 }
 
+bool ZNMethod::supports_entry_barrier(nmethod* nm) {
+  BarrierSetNMethod* const bs = BarrierSet::barrier_set()->barrier_set_nmethod();
+  if (bs != NULL) {
+    return bs->supports_entry_barrier(nm);
+  }
+
+  return false;
+}
+
 bool ZNMethod::is_armed(nmethod* nm) {
   BarrierSetNMethod* const bs = BarrierSet::barrier_set()->barrier_set_nmethod();
   if (bs != NULL) {

src/hotspot/share/gc/z/zNMethod.hpp

@@ -43,6 +43,8 @@ public:
   static void unregister_nmethod(nmethod* nm);
   static void flush_nmethod(nmethod* nm);
 
+  static bool supports_entry_barrier(nmethod* nm);
+
   static bool is_armed(nmethod* nm);
   static void disarm(nmethod* nm);
 

src/hotspot/share/gc/z/zRootsIterator.cpp

@@ -146,14 +146,15 @@ private:
 
 public:
   ZRootsIteratorCodeBlobClosure(ZRootsIteratorClosure* cl) :
-    _cl(cl),
-    _should_disarm_nmethods(cl->should_disarm_nmethods()) {}
+      _cl(cl),
+      _should_disarm_nmethods(cl->should_disarm_nmethods()) {}
 
   virtual void do_code_blob(CodeBlob* cb) {
     nmethod* const nm = cb->as_nmethod_or_null();
     if (nm != NULL && nm->oops_do_try_claim()) {
       ZNMethod::nmethod_oops_do(nm, _cl);
-      assert(ZNMethod::is_armed(nm) == _should_disarm_nmethods, "Invalid state");
+      assert(!ZNMethod::supports_entry_barrier(nm) ||
+             ZNMethod::is_armed(nm) == _should_disarm_nmethods, "Invalid state");
       if (_should_disarm_nmethods) {
         ZNMethod::disarm(nm);
       }