--- old/src/share/vm/gc/g1/heapRegionManager.cpp	2015-05-27 14:30:59.904169325 -0400
+++ new/src/share/vm/gc/g1/heapRegionManager.cpp	2015-05-27 14:30:59.268133082 -0400
@@ -278,6 +278,31 @@
   return num_regions;
 }
 
+uint HeapRegionManager::find_highest_available(bool* expanded) {
+  // Loop downwards from the highest region index, looking for an
+  // entry which is either free or not yet committed.  If not yet
+  // committed, expand_at that index, and set the 'expanded' output
+  // bool result to true.
+  uint curr = max_length() - 1;
+  while (curr != 0) {
+    HeapRegion *hr = _regions.get_by_index(curr);
+    if (hr == NULL) {
+      uint res = expand_at(curr, 1);
+      if (res == 1) {
+	*expanded = true;
+	return curr;
+      }
+    } else {
+      if (hr->is_free()) {
+	*expanded = false;
+	return curr;
+      }
+    }
+    curr--;
+  }
+  return G1_NO_HRM_INDEX;
+}
+
 void HeapRegionManager::par_iterate(HeapRegionClosure* blk, uint worker_id, HeapRegionClaimer* hrclaimer, bool concurrent) const {
   const uint start_index = hrclaimer->start_region_for_worker(worker_id);
 
@@ -436,7 +461,7 @@
     num_committed++;
     HeapRegion* hr = _regions.get_by_index(i);
     guarantee(hr != NULL, err_msg("invariant: i: %u", i));
-    guarantee(!prev_committed || hr->bottom() == prev_end,
+    guarantee(!prev_committed || hr->bottom() == prev_end || hr->is_archive(),
               err_msg("invariant i: %u "HR_FORMAT" prev_end: "PTR_FORMAT,
                       i, HR_FORMAT_PARAMS(hr), p2i(prev_end)));
     guarantee(hr->hrm_index() == i,