--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/g1/g1FullGCCompactionPoint.cpp	Tue Nov 14 11:33:23 2017 +0100
@@ -0,0 +1,145 @@
+/*
+ * Copyright (c) 2017, 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
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "gc/g1/g1FullGCCompactionPoint.hpp"
+#include "gc/g1/heapRegion.hpp"
+#include "oops/oop.inline.hpp"
+#include "utilities/debug.hpp"
+
+G1FullGCCompactionPoint::G1FullGCCompactionPoint() :
+    _current_region(NULL),
+    _threshold(NULL),
+    _compaction_top(NULL) {
+  _compaction_regions = new (ResourceObj::C_HEAP, mtGC) GrowableArray<HeapRegion*>(32, true, mtGC);
+  _compaction_region_iterator = _compaction_regions->begin();
+}
+
+G1FullGCCompactionPoint::~G1FullGCCompactionPoint() {
+  delete _compaction_regions;
+}
+
+void G1FullGCCompactionPoint::update() {
+  if (is_initialized()) {
+    _current_region->set_compaction_top(_compaction_top);
+  }
+}
+
+void G1FullGCCompactionPoint::initialize_values(bool init_threshold) {
+  _compaction_top = _current_region->compaction_top();
+  if (init_threshold) {
+    _threshold = _current_region->initialize_threshold();
+  }
+}
+
+bool G1FullGCCompactionPoint::has_regions() {
+  return !_compaction_regions->is_empty();
+}
+
+bool G1FullGCCompactionPoint::is_initialized() {
+  return _current_region != NULL;
+}
+
+void G1FullGCCompactionPoint::initialize(HeapRegion* hr, bool init_threshold) {
+  _current_region = hr;
+  initialize_values(init_threshold);
+}
+
+HeapRegion* G1FullGCCompactionPoint::current_region() {
+  return *_compaction_region_iterator;
+}
+
+HeapRegion* G1FullGCCompactionPoint::next_region() {
+  HeapRegion* next = *(++_compaction_region_iterator);
+  assert(next != NULL, "Must return valid region");
+  return next;
+}
+
+GrowableArray<HeapRegion*>* G1FullGCCompactionPoint::regions() {
+  return _compaction_regions;
+}
+
+bool G1FullGCCompactionPoint::object_will_fit(size_t size) {
+  size_t space_left = pointer_delta(_current_region->end(), _compaction_top);
+  return size <= space_left;
+}
+
+void G1FullGCCompactionPoint::switch_region() {
+  // Save compaction top in the region.
+  _current_region->set_compaction_top(_compaction_top);
+  // Get the next region and re-initialize the values.
+  _current_region = next_region();
+  initialize_values(true);
+}
+
+void G1FullGCCompactionPoint::forward(oop object, size_t size) {
+  assert(_current_region != NULL, "Must have been initialized");
+
+  // Ensure the object fit in the current region.
+  while (!object_will_fit(size)) {
+    switch_region();
+  }
+
+  // Store a forwarding pointer if the object should be moved.
+  if ((HeapWord*)object != _compaction_top) {
+    object->forward_to(oop(_compaction_top));
+  } else {
+    if (object->forwardee() != NULL) {
+      // Object should not move but mark-word is used so it looks like the
+      // object is forwarded. Need to clear the mark and it's no problem
+      // since it will be restored by preserved marks. There is an exception
+      // with BiasedLocking, in this case forwardee() will return NULL
+      // even if the mark-word is used. This is no problem since
+      // forwardee() will return NULL in the compaction phase as well.
+      object->init_mark();
+    } else {
+      // Make sure object has the correct mark-word set or that it will be
+      // fixed when restoring the preserved marks.
+      assert(object->mark() == markOopDesc::prototype_for_object(object) || // Correct mark
+             object->mark()->must_be_preserved(object) || // Will be restored by PreservedMarksSet
+             (UseBiasedLocking && object->has_bias_pattern()), // Will be restored by BiasedLocking
+             "should have correct prototype obj: " PTR_FORMAT " mark: " PTR_FORMAT " prototype: " PTR_FORMAT,
+             p2i(object), p2i(object->mark()), p2i(markOopDesc::prototype_for_object(object)));
+    }
+    assert(object->forwardee() == NULL, "should be forwarded to NULL");
+  }
+
+  // Update compaction values.
+  _compaction_top += size;
+  if (_compaction_top > _threshold) {
+    _threshold = _current_region->cross_threshold(_compaction_top - size, _compaction_top);
+  }
+}
+
+void G1FullGCCompactionPoint::add(HeapRegion* hr) {
+  _compaction_regions->append(hr);
+}
+
+void G1FullGCCompactionPoint::merge(G1FullGCCompactionPoint* other) {
+   _compaction_regions->appendAll(other->regions());
+}
+
+HeapRegion* G1FullGCCompactionPoint::remove_last() {
+  return _compaction_regions->pop();
+}