Add dex file intermediate representation

Add an intermediate representation, constructed from the DexFile
utilities, that can be used to optimize the layout and re-emit dex
files.

BUG: 29921113
TEST: TODO: Add dex files to compare output with dexdump

(cherry-picked from commit af14d9f551e6169c201dc7981d9cfbcb53c7d2c7)

Change-Id: I3dacb78fad5228e43d77f20b110bd40e0e116cdb
diff --git a/dexlayout/dexlayout.h b/dexlayout/dexlayout.h
new file mode 100644
index 0000000..bae587d
--- /dev/null
+++ b/dexlayout/dexlayout.h
@@ -0,0 +1,60 @@
+/*
+ * 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.
+ *
+ * Header file of the dexlayout utility.
+ *
+ * This is a tool to read dex files into an internal representation,
+ * reorganize the representation, and emit dex files with a better
+ * file layout.
+ */
+
+#ifndef ART_DEXLAYOUT_DEXLAYOUT_H_
+#define ART_DEXLAYOUT_DEXLAYOUT_H_
+
+#include <stdint.h>
+#include <stdio.h>
+
+namespace art {
+
+/* Supported output formats. */
+enum OutputFormat {
+  kOutputPlain = 0,  // default
+  kOutputXml,        // XML-style
+};
+
+/* Command-line options. */
+struct Options {
+  bool build_dex_ir_;
+  bool checksum_only_;
+  bool disassemble_;
+  bool exports_only_;
+  bool ignore_bad_checksum_;
+  bool show_annotations_;
+  bool show_cfg_;
+  bool show_file_headers_;
+  bool show_section_headers_;
+  bool verbose_;
+  OutputFormat output_format_;
+  const char* output_file_name_;
+};
+
+/* Prototypes. */
+extern struct Options options_;
+extern FILE* out_file_;
+int ProcessFile(const char* file_name);
+
+}  // namespace art
+
+#endif  // ART_DEXLAYOUT_DEXLAYOUT_H_