8329570: G1: Excessive is_obj_dead_cond calls in verification

Reviewed-by: phh
Backport-of: 29992e1fca4faef0fe0ac453c7e78db4628d5e70

src/hotspot/share/gc/g1/heapRegion.cpp

@@ -493,6 +493,7 @@ class G1VerificationClosure : public BasicOopIterateClosure {
   }
 
   void set_containing_obj(oop obj) {
+    assert(!_g1h->is_obj_dead_cond(obj, _vo), "Precondition");
     _containing_obj = obj;
   }
 
@@ -519,8 +520,6 @@ class VerifyLiveClosure : public G1VerificationClosure {
   template <class T>
   void do_oop_work(T* p) {
     assert(_containing_obj != NULL, "Precondition");
-    assert(!_g1h->is_obj_dead_cond(_containing_obj, _vo),
-      "Precondition");
     verify_liveness(p);
   }
 
@@ -577,8 +576,6 @@ class VerifyRemSetClosure : public G1VerificationClosure {
   template <class T>
   void do_oop_work(T* p) {
     assert(_containing_obj != NULL, "Precondition");
-    assert(!_g1h->is_obj_dead_cond(_containing_obj, _vo),
-      "Precondition");
     verify_remembered_set(p);
   }