Mercurial > hg > graal-compiler

view src/share/vm/classfile/altHashing.hpp @ 9126:bc26f978b0ce

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
HotSpotResolvedObjectType: implement hasFinalizeSubclass() correctly don't use the (wrong) cached value, but ask the runtime on each request. Fixes regression on xml.* benchmarks @ specjvm2008. The problem was: After the constructor of Object was deoptimized due to an assumption violation, it was recompiled again after some time. However, on recompilation, the value of hasFinalizeSubclass for the class was not updated and it was compiled again with a, now wrong, assumption, which then triggers deoptimization again. This was repeated until it hit the recompilation limit (defined by PerMethodRecompilationCutoff), and therefore only executed by the interpreter from now on, causing the performance regression.
author Bernhard Urban <bernhard.urban@jku.at>
date Mon, 15 Apr 2013 19:54:58 +0200
parents e9140bf80b4a
children cd6b3f1a94ff
line wrap: on
line source

/*
 * Copyright (c) 2012, 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 jint Integer_rotateLeft(jint i, int distance) {
    return (i << distance) | (((juint)i) >> (32-distance));
  }
  static jint murmur3_32(const int* data, int len);
  static jint murmur3_32(jint seed, const int* data, int len);

#ifndef PRODUCT
  // Hashing functions used for internal testing
  static jint murmur3_32(const jbyte* data, int len);
  static jint murmur3_32(const jchar* data, int len);
  static void testMurmur3_32_ByteArray();
  static void testEquivalentHashes();
#endif // PRODUCT

 public:
  static jint compute_seed();
  static jint murmur3_32(jint seed, const jbyte* data, int len);
  static jint murmur3_32(jint seed, const jchar* data, int len);
  NOT_PRODUCT(static void test_alt_hash();)
};
#endif // SHARE_VM_CLASSFILE_ALTHASHING_HPP