1 /* 2 * Copyright (c) 2012, 2016, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_VM_CLASSFILE_ALTHASHING_HPP 26 #define SHARE_VM_CLASSFILE_ALTHASHING_HPP 27 28 #include "prims/jni.h" 29 #include "classfile/symbolTable.hpp" 30 31 /** 32 * Hashing utilities. 33 * 34 * Implementation of Murmur3 hashing. 35 * This code was translated from src/share/classes/sun/misc/Hashing.java 36 * code in the JDK. 37 */ 38 39 class AltHashing : AllStatic { 40 friend class AltHashingTest; 41 42 // utility function copied from java/lang/Integer 43 static juint Integer_rotateLeft(juint i, int distance) { 44 return (i << distance) | (i >> (32 - distance)); 45 } 46 static juint murmur3_32(const int* data, int len); 47 static juint murmur3_32(juint seed, const int* data, int len); 48 49 public: 50 static juint compute_seed(); 51 static juint murmur3_32(juint seed, const jbyte* data, int len); 52 static juint murmur3_32(juint seed, const jchar* data, int len); 53 }; 54 #endif // SHARE_VM_CLASSFILE_ALTHASHING_HPP