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diff --git a/compiler/optimizing/boolean_simplifier.h b/compiler/optimizing/boolean_simplifier.h
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+/*
+ * Copyright (C) 2015 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.
+ */
+
+// This optimization recognizes a common pattern where a boolean value is
+// either casted to an integer or negated by selecting from zero/one integer
+// constants with an If statement. Because boolean values are internally
+// represented as zero/one, we can safely replace the pattern with a suitable
+// condition instruction.
+
+// Example: Negating a boolean value
+//     B1:
+//       z1   ParameterValue
+//       i2   IntConstant 0
+//       i3   IntConstant 1
+//       v4   Goto B2
+//     B2:
+//       z5   NotEquals [ z1 i2 ]
+//       v6   If [ z5 ] then B3 else B4
+//     B3:
+//       v7   Goto B5
+//     B4:
+//       v8   Goto B5
+//     B5:
+//       i9   Phi [ i3 i2 ]
+//       v10  Return [ i9 ]
+// turns into
+//     B1:
+//       z1   ParameterValue
+//       i2   IntConstant 0
+//       v4   Goto B2
+//     B2:
+//       z11  Equals [ z1 i2 ]
+//       v10  Return [ z11 ]
+//     B3, B4, B5: removed
+
+// Note: in order to recognize empty blocks, this optimization must be run
+// after the instruction simplifier has removed redundant suspend checks.
+
+#ifndef ART_COMPILER_OPTIMIZING_BOOLEAN_SIMPLIFIER_H_
+#define ART_COMPILER_OPTIMIZING_BOOLEAN_SIMPLIFIER_H_
+
+#include "optimization.h"
+
+namespace art {
+
+class HBooleanSimplifier : public HOptimization {
+ public:
+  explicit HBooleanSimplifier(HGraph* graph)
+    : HOptimization(graph, true, kBooleanSimplifierPassName) {}
+
+  void Run() OVERRIDE;
+
+  static constexpr const char* kBooleanSimplifierPassName = "boolean_simplifier";
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(HBooleanSimplifier);
+};
+
+}  // namespace art
+
+#endif  // ART_COMPILER_OPTIMIZING_BOOLEAN_SIMPLIFIER_H_