73     ShenandoahConnectionMatrix* matrix = _heap->connection_matrix();
  74     SCMObjToScanQueueSet* queues = _heap->partial_gc()->task_queues();
  75     SCMObjToScanQueue* q = queues->queue(worker_id);
  76 
  77     // Step 1: Process ordinary GC roots.
  78     {
  79       PartialEvacuateUpdateRootsClosure roots_cl(q);
  80       CLDToOopClosure cld_cl(&roots_cl);
  81       MarkingCodeBlobClosure code_cl(&roots_cl, CodeBlobToOopClosure::FixRelocations);
  82       _rp->process_all_roots(&roots_cl, &roots_cl, &cld_cl, &code_cl, worker_id);
  83     }
  84     if (check_and_handle_cancelled_gc()) return;
  85 
  86     PartialEvacuateUpdateHeapClosure cl(q);
  87 
  88     // Step 2: Process all root regions.
  89     {
  90       ShenandoahHeapRegion* r = _root_regions->claim_next();
  91       while (r != NULL) {
  92         assert(r->is_root(), "must be root region");
  93         if (! r->is_humongous_continuation()) {
  94           _heap->marked_object_oop_iterate(r, &cl);
  95         }
  96         r->set_root(false);
  97         if (check_and_handle_cancelled_gc()) return;
  98         r = _root_regions->claim_next();
  99       }
 100     }
 101     if (check_and_handle_cancelled_gc()) return;
 102 
 103     // Step 3: Drain all outstanding work in queues.
 104     {
 105       int seed = 17;
 106       SCMTask task;
 107 
 108       uint stride = ShenandoahMarkLoopStride;
 109 
 110       while (true) {
 111         if (check_and_handle_cancelled_gc()) return;
 112 
 113         for (uint i = 0; i < stride; i++) {
 114           if ((q->pop_buffer(task) ||
 115                q->pop_local(task) ||

  73     ShenandoahConnectionMatrix* matrix = _heap->connection_matrix();
  74     SCMObjToScanQueueSet* queues = _heap->partial_gc()->task_queues();
  75     SCMObjToScanQueue* q = queues->queue(worker_id);
  76 
  77     // Step 1: Process ordinary GC roots.
  78     {
  79       PartialEvacuateUpdateRootsClosure roots_cl(q);
  80       CLDToOopClosure cld_cl(&roots_cl);
  81       MarkingCodeBlobClosure code_cl(&roots_cl, CodeBlobToOopClosure::FixRelocations);
  82       _rp->process_all_roots(&roots_cl, &roots_cl, &cld_cl, &code_cl, worker_id);
  83     }
  84     if (check_and_handle_cancelled_gc()) return;
  85 
  86     PartialEvacuateUpdateHeapClosure cl(q);
  87 
  88     // Step 2: Process all root regions.
  89     {
  90       ShenandoahHeapRegion* r = _root_regions->claim_next();
  91       while (r != NULL) {
  92         assert(r->is_root(), "must be root region");

  93         _heap->marked_object_oop_iterate(r, &cl);

  94         r->set_root(false);
  95         if (check_and_handle_cancelled_gc()) return;
  96         r = _root_regions->claim_next();
  97       }
  98     }
  99     if (check_and_handle_cancelled_gc()) return;
 100 
 101     // Step 3: Drain all outstanding work in queues.
 102     {
 103       int seed = 17;
 104       SCMTask task;
 105 
 106       uint stride = ShenandoahMarkLoopStride;
 107 
 108       while (true) {
 109         if (check_and_handle_cancelled_gc()) return;
 110 
 111         for (uint i = 0; i < stride; i++) {
 112           if ((q->pop_buffer(task) ||
 113                q->pop_local(task) ||