Add atomic method reference map
Less RAM usage and faster than using a normal map with
MethodReference. Speed is faster by avoiding locking and tree
traversal. RAM usage is lower since the map usually had a value
for most method references.
Plan on using for marking methods for dex2dex, storing compiled
methods. Also use the new map for VerifiedMethods (refactoring).
Added test.
Bug: 32641252
Test: test-art-host-run-test
Change-Id: I46268031b8e0daf9be3597145cf6ecf579a039e2
diff --git a/compiler/utils/atomic_method_ref_map.h b/compiler/utils/atomic_method_ref_map.h
new file mode 100644
index 0000000..f0db231
--- /dev/null
+++ b/compiler/utils/atomic_method_ref_map.h
@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2016 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_COMPILER_UTILS_ATOMIC_METHOD_REF_MAP_H_
+#define ART_COMPILER_UTILS_ATOMIC_METHOD_REF_MAP_H_
+
+#include "base/dchecked_vector.h"
+#include "method_reference.h"
+#include "safe_map.h"
+
+namespace art {
+
+class DexFile;
+
+// Used by CompilerCallbacks to track verification information from the Runtime.
+template <typename T>
+class AtomicMethodRefMap {
+ public:
+ explicit AtomicMethodRefMap() {}
+ ~AtomicMethodRefMap() {}
+
+ // Atomically swap the element in if the existing value matches expected.
+ enum InsertResult {
+ kInsertResultInvalidDexFile,
+ kInsertResultCASFailure,
+ kInsertResultSuccess,
+ };
+ InsertResult Insert(MethodReference ref, const T& expected, const T& desired);
+
+ // Retreive an item, returns false if the dex file is not added.
+ bool Get(MethodReference ref, T* out) const;
+
+ // Dex files must be added before method references belonging to them can be used as keys. Not
+ // thread safe.
+ void AddDexFile(const DexFile* dex_file);
+
+ // Visit all of the dex files and elements.
+ template <typename Visitor>
+ void Visit(const Visitor& visitor);
+
+ private:
+ // Verified methods. The method array is fixed to avoid needing a lock to extend it.
+ using ElementArray = dchecked_vector<Atomic<T>>;
+ using DexFileArrays = SafeMap<const DexFile*, ElementArray>;
+
+ const ElementArray* GetArray(const DexFile* dex_file) const;
+ ElementArray* GetArray(const DexFile* dex_file);
+
+ DexFileArrays arrays_;
+};
+
+} // namespace art
+
+#endif // ART_COMPILER_UTILS_ATOMIC_METHOD_REF_MAP_H_