--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/shared/barrierSet.inline.hpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,94 @@
+/*
+ * Copyright (c) 2001, 2015, 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.
+ *
+ */
+
+#ifndef SHARE_VM_GC_SHARED_BARRIERSET_INLINE_HPP
+#define SHARE_VM_GC_SHARED_BARRIERSET_INLINE_HPP
+
+#include "gc/shared/barrierSet.hpp"
+#include "gc/shared/cardTableModRefBS.inline.hpp"
+#include "utilities/align.hpp"
+
+// Inline functions of BarrierSet, which de-virtualize certain
+// performance-critical calls when the barrier is the most common
+// card-table kind.
+
+inline bool BarrierSet::devirtualize_reference_writes() const {
+  switch (kind()) {
+  case CardTableForRS:
+  case CardTableExtension:
+    return true;
+  default:
+    return false;
+  }
+}
+
+template <class T> void BarrierSet::write_ref_field_pre(T* field, oop new_val) {
+  if (devirtualize_reference_writes()) {
+    barrier_set_cast<CardTableModRefBS>(this)->inline_write_ref_field_pre(field, new_val);
+  } else {
+    write_ref_field_pre_work(field, new_val);
+  }
+}
+
+void BarrierSet::write_ref_field(void* field, oop new_val, bool release) {
+  if (devirtualize_reference_writes()) {
+    barrier_set_cast<CardTableModRefBS>(this)->inline_write_ref_field(field, new_val, release);
+  } else {
+    write_ref_field_work(field, new_val, release);
+  }
+}
+
+// count is number of array elements being written
+void BarrierSet::write_ref_array(HeapWord* start, size_t count) {
+  assert(count <= (size_t)max_intx, "count too large");
+  HeapWord* end = (HeapWord*)((char*)start + (count*heapOopSize));
+  // In the case of compressed oops, start and end may potentially be misaligned;
+  // so we need to conservatively align the first downward (this is not
+  // strictly necessary for current uses, but a case of good hygiene and,
+  // if you will, aesthetics) and the second upward (this is essential for
+  // current uses) to a HeapWord boundary, so we mark all cards overlapping
+  // this write. If this evolves in the future to calling a
+  // logging barrier of narrow oop granularity, like the pre-barrier for G1
+  // (mentioned here merely by way of example), we will need to change this
+  // interface, so it is "exactly precise" (if i may be allowed the adverbial
+  // redundancy for emphasis) and does not include narrow oop slots not
+  // included in the original write interval.
+  HeapWord* aligned_start = align_down(start, HeapWordSize);
+  HeapWord* aligned_end   = align_up  (end,   HeapWordSize);
+  // If compressed oops were not being used, these should already be aligned
+  assert(UseCompressedOops || (aligned_start == start && aligned_end == end),
+         "Expected heap word alignment of start and end");
+  write_ref_array_work(MemRegion(aligned_start, aligned_end));
+}
+
+
+inline void BarrierSet::write_region(MemRegion mr) {
+  if (devirtualize_reference_writes()) {
+    barrier_set_cast<CardTableModRefBS>(this)->inline_write_region(mr);
+  } else {
+    write_region_work(mr);
+  }
+}
+
+#endif // SHARE_VM_GC_SHARED_BARRIERSET_INLINE_HPP