Refactor immune region logic into its own file.
Added immune_region.cc/.h in the collector directory. Changed the
functionality to no longer assume spaces are added to immune region
in ascending order.
Change-Id: Id1d643b3849ad2695e8a151dbbb74a5035644472
diff --git a/runtime/gc/collector/immune_region.h b/runtime/gc/collector/immune_region.h
new file mode 100644
index 0000000..21d0b43
--- /dev/null
+++ b/runtime/gc/collector/immune_region.h
@@ -0,0 +1,65 @@
+/*
+ * 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_COLLECTOR_IMMUNE_REGION_H_
+#define ART_RUNTIME_GC_COLLECTOR_IMMUNE_REGION_H_
+
+#include "base/macros.h"
+#include "base/mutex.h"
+#include "gc/space/space-inl.h"
+
+namespace art {
+namespace mirror {
+class Object;
+} // namespace mirror
+namespace gc {
+namespace space {
+class ContinuousSpace;
+} // namespace space
+
+namespace collector {
+
+// An immune region is a continuous region of memory for which all objects contained are assumed to
+// be marked. This is used as an optimization in the GC to avoid needing to test the mark bitmap of
+// the zygote, image spaces, and sometimes non moving spaces. Doing the ContainsObject check is
+// faster than doing a bitmap read. There is no support for discontinuous spaces and you need to be
+// careful that your immune region doesn't contain any large objects.
+class ImmuneRegion {
+ public:
+ ImmuneRegion();
+ void Reset();
+ bool AddContinuousSpace(space::ContinuousSpace* space)
+ EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
+ bool ContainsSpace(const space::ContinuousSpace* space) const;
+ // Returns true if an object is inside of the immune region (assumed to be marked).
+ bool ContainsObject(const mirror::Object* obj) const ALWAYS_INLINE {
+ return obj >= begin_ && obj < end_;
+ }
+
+ private:
+ bool IsEmpty() const {
+ return begin_ == end_;
+ }
+
+ mirror::Object* begin_;
+ mirror::Object* end_;
+};
+
+} // namespace collector
+} // namespace gc
+} // namespace art
+
+#endif // ART_RUNTIME_GC_COLLECTOR_IMMUNE_REGION_H_