--- old/src/hotspot/share/gc/g1/g1CollectedHeap.hpp	2019-03-13 14:02:58.382956089 +0100
+++ new/src/hotspot/share/gc/g1/g1CollectedHeap.hpp	2019-03-13 14:02:58.169950305 +0100
@@ -143,9 +143,8 @@
   // Closures used in implementation.
   friend class G1ParScanThreadState;
   friend class G1ParScanThreadStateSet;
-  friend class G1ParTask;
+  friend class G1EvacuateRegionsTask;
   friend class G1PLABAllocator;
-  friend class G1PrepareCompactClosure;
 
   // Other related classes.
   friend class HeapRegionClaimer;
@@ -519,6 +518,8 @@
 
   WorkGang* workers() const { return _workers; }
 
+  Tickspan run_task(AbstractGangTask* task, uint num_workers = 0);
+
   G1Allocator* allocator() {
     return _allocator;
   }
@@ -738,10 +739,11 @@
 
   void calculate_collection_set(G1EvacuationInfo& evacuation_info, double target_pause_time_ms);
 
-  // Actually do the work of evacuating the collection set.
-  void evacuate_collection_set(G1ParScanThreadStateSet* per_thread_states);
+  // Actually do the work of evacuating the parts of the collection set.
+  void evacuate_initial_collection_set(G1ParScanThreadStateSet* per_thread_states);
   void evacuate_optional_collection_set(G1ParScanThreadStateSet* per_thread_states);
-  void evacuate_optional_regions(G1ParScanThreadStateSet* per_thread_states, G1OptionalCSet* ocset);
+  // Evacuate the next set of optional regions.
+  void evacuate_next_optional_regions(G1ParScanThreadStateSet* per_thread_states);
 
   void pre_evacuate_collection_set(G1EvacuationInfo& evacuation_info);
   void post_evacuate_collection_set(G1EvacuationInfo& evacuation_info, G1ParScanThreadStateSet* pss);
@@ -1424,7 +1426,7 @@
   size_t _term_attempts;
 
   void start_term_time() { _term_attempts++; _start_term = os::elapsedTime(); }
-  void end_term_time() { _term_time += os::elapsedTime() - _start_term; }
+  void end_term_time() { _term_time += (os::elapsedTime() - _start_term); }
 protected:
   G1CollectedHeap*              _g1h;
   G1ParScanThreadState*         _par_scan_state;