--- a/hotspot/src/share/vm/gc_implementation/g1/heapRegion.inline.hpp	Tue Jan 10 20:02:41 2012 +0100
+++ b/hotspot/src/share/vm/gc_implementation/g1/heapRegion.inline.hpp	Tue Jan 10 18:58:13 2012 -0500
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2012, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -55,4 +55,71 @@
   return _offsets.block_start_const(p);
 }
 
+inline void HeapRegion::note_start_of_marking() {
+  init_top_at_conc_mark_count();
+  _next_marked_bytes = 0;
+  _next_top_at_mark_start = top();
+}
+
+inline void HeapRegion::note_end_of_marking() {
+  _prev_top_at_mark_start = _next_top_at_mark_start;
+  _prev_marked_bytes = _next_marked_bytes;
+  _next_marked_bytes = 0;
+
+  assert(_prev_marked_bytes <=
+         (size_t) pointer_delta(prev_top_at_mark_start(), bottom()) *
+         HeapWordSize, "invariant");
+}
+
+inline void HeapRegion::note_start_of_copying(bool during_initial_mark) {
+  if (during_initial_mark) {
+    if (is_survivor()) {
+      assert(false, "should not allocate survivors during IM");
+    } else {
+      // During initial-mark we'll explicitly mark any objects on old
+      // regions that are pointed to by roots. Given that explicit
+      // marks only make sense under NTAMS it'd be nice if we could
+      // check that condition if we wanted to. Given that we don't
+      // know where the top of this region will end up, we simply set
+      // NTAMS to the end of the region so all marks will be below
+      // NTAMS. We'll set it to the actual top when we retire this region.
+      _next_top_at_mark_start = end();
+    }
+  } else {
+    if (is_survivor()) {
+      // This is how we always allocate survivors.
+      assert(_next_top_at_mark_start == bottom(), "invariant");
+    } else {
+      // We could have re-used this old region as to-space over a
+      // couple of GCs since the start of the concurrent marking
+      // cycle. This means that [bottom,NTAMS) will contain objects
+      // copied up to and including initial-mark and [NTAMS, top)
+      // will contain objects copied during the concurrent marking cycle.
+      assert(top() >= _next_top_at_mark_start, "invariant");
+    }
+  }
+}
+
+inline void HeapRegion::note_end_of_copying(bool during_initial_mark) {
+  if (during_initial_mark) {
+    if (is_survivor()) {
+      assert(false, "should not allocate survivors during IM");
+    } else {
+      // See the comment for note_start_of_copying() for the details
+      // on this.
+      assert(_next_top_at_mark_start == end(), "pre-condition");
+      _next_top_at_mark_start = top();
+    }
+  } else {
+    if (is_survivor()) {
+      // This is how we always allocate survivors.
+      assert(_next_top_at_mark_start == bottom(), "invariant");
+    } else {
+      // See the comment for note_start_of_copying() for the details
+      // on this.
+      assert(top() >= _next_top_at_mark_start, "invariant");
+    }
+  }
+}
+
 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGION_INLINE_HPP