Initiate a constant propagation pass in the optimizing compiler.

- Perform constant folding on int and long additions and subtractions in
  the optimizing compiler.
- Apply constant folding to conditions and comparisons.

Change-Id: Ic88783a3c975fda777c74c531e257fa777be42eb

1 files changed, 43 insertions, 0 deletions

diff --git a/compiler/optimizing/constant_propagation.h b/compiler/optimizing/constant_propagation.h
new file mode 100644
index 0000000000..0729881888
--- /dev/null
+++ b/compiler/optimizing/constant_propagation.h
@@ -0,0 +1,43 @@
+/*
+ * 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_COMPILER_OPTIMIZING_CONSTANT_PROPAGATION_H_
+#define ART_COMPILER_OPTIMIZING_CONSTANT_PROPAGATION_H_
+
+#include "nodes.h"
+
+namespace art {
+
+/**
+ * Optimization pass performing a simple constant propagation on the
+ * SSA form.
+ */
+class ConstantPropagation : public ValueObject {
+ public:
+  explicit ConstantPropagation(HGraph* graph)
+    : graph_(graph) {}
+
+  void Run();
+
+ private:
+  HGraph* const graph_;
+
+  DISALLOW_COPY_AND_ASSIGN(ConstantPropagation);
+};
+
+}  // namespace art
+
+#endif  // ART_COMPILER_OPTIMIZING_CONSTANT_PROPAGATION_H_