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diff --git a/compiler/optimizing/loop_optimization.h b/compiler/optimizing/loop_optimization.h
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+/*
+ * 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_OPTIMIZING_LOOP_OPTIMIZATION_H_
+#define ART_COMPILER_OPTIMIZING_LOOP_OPTIMIZATION_H_
+
+#include <string>
+
+#include "induction_var_range.h"
+#include "nodes.h"
+#include "optimization.h"
+
+namespace art {
+
+/**
+ * Loop optimizations. Builds a loop hierarchy and applies optimizations to
+ * the detected nested loops, such as removal of dead induction and empty loops.
+ */
+class HLoopOptimization : public HOptimization {
+ public:
+  HLoopOptimization(HGraph* graph, HInductionVarAnalysis* induction_analysis);
+
+  void Run() OVERRIDE;
+
+  static constexpr const char* kLoopOptimizationPassName = "loop_optimization";
+
+ private:
+  /**
+   * A single loop inside the loop hierarchy representation.
+   */
+  struct LoopNode : public ArenaObject<kArenaAllocInductionVarAnalysis> {
+    explicit LoopNode(HLoopInformation* lp_info)
+        : loop_info(lp_info),
+          outer(nullptr),
+          inner(nullptr),
+          previous(nullptr),
+          next(nullptr) {}
+    const HLoopInformation* const loop_info;
+    LoopNode* outer;
+    LoopNode* inner;
+    LoopNode* previous;
+    LoopNode* next;
+  };
+
+  void AddLoop(HLoopInformation* loop_info);
+  void RemoveLoop(LoopNode* node);
+
+  void TraverseLoopsInnerToOuter(LoopNode* node);
+
+  void SimplifyInduction(LoopNode* node);
+  void RemoveIfEmptyLoop(LoopNode* node);
+
+  void ReplaceAllUses(HInstruction* instruction,
+                      HInstruction* replacement,
+                      HInstruction* exclusion);
+
+  // Range analysis based on induction variables.
+  InductionVarRange induction_range_;
+
+  // Phase-local heap memory allocator for the loop optimizer. Storage obtained
+  // through this allocator is released when the loop optimizer is done.
+  ArenaAllocator loop_allocator_;
+
+  // Entries into the loop hierarchy representation.
+  LoopNode* top_loop_;
+  LoopNode* last_loop_;
+
+  friend class LoopOptimizationTest;
+
+  DISALLOW_COPY_AND_ASSIGN(HLoopOptimization);
+};
+
+}  // namespace art
+
+#endif  // ART_COMPILER_OPTIMIZING_LOOP_OPTIMIZATION_H_