/*

 * Copyright (c) 2012, 2014, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#ifndef SHARE_VM_CLASSFILE_ALTHASHING_HPP

#define SHARE_VM_CLASSFILE_ALTHASHING_HPP

#include "prims/jni.h"

#include "classfile/symbolTable.hpp"

/**

 * Hashing utilities.

 *

 * Implementation of Murmur3 hashing.

 * This code was translated from src/share/classes/sun/misc/Hashing.java

 * code in the JDK.

 */

class AltHashing : AllStatic {

  // utility function copied from java/lang/Integer

  static juint Integer_rotateLeft(juint i, int distance) {

    return (i << distance) | (i >> (32-distance));

  }

  static juint murmur3_32(const int* data, int len);

  static juint murmur3_32(juint seed, const int* data, int len);

#ifndef PRODUCT

  // Hashing functions used for internal testing

  static juint murmur3_32(const jbyte* data, int len);

  static juint murmur3_32(const jchar* data, int len);

  static void testMurmur3_32_ByteArray();

  static void testEquivalentHashes();

#endif // PRODUCT

 public:

  static juint compute_seed();

  static juint murmur3_32(juint seed, const jbyte* data, int len);

  static juint murmur3_32(juint seed, const jchar* data, int len);

  NOT_PRODUCT(static void test_alt_hash();)

};

#endif // SHARE_VM_CLASSFILE_ALTHASHING_HPP