Add GcRoot to clean up and enforce read barriers.

Introduce a value-type wrapper around Object* for GC roots so that 1)
we won't have to directly add the read barrier code in many places and
2) we can avoid accidentally bypassing/missing read barriers on GC
roots (the GcRoot interface ensures that the read barrier is executed
on a read).

The jdwp test passed.

Bug: 12687968
Change-Id: Ib167c7c325b3c7e3900133578815f04d219972a1

1 files changed, 33 insertions, 0 deletions

diff --git a/runtime/gc_root-inl.h b/runtime/gc_root-inl.h
new file mode 100644
index 0000000000..482f7bca0e
--- /dev/null
+++ b/runtime/gc_root-inl.h
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ART_RUNTIME_GC_ROOT_INL_H_
+#define ART_RUNTIME_GC_ROOT_INL_H_
+
+#include "gc_root.h"
+
+#include "read_barrier-inl.h"
+
+namespace art {
+
+template<class MirrorType>
+template<ReadBarrierOption kReadBarrierOption>
+inline MirrorType* GcRoot<MirrorType>::Read() {
+  return ReadBarrier::BarrierForRoot<MirrorType, kReadBarrierOption>(&root_);
+}
+
+}  // namespace art
+#endif  // ART_RUNTIME_GC_ROOT_INL_H_