001/*
002 * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004 *
005 * This code is free software; you can redistribute it and/or modify it
006 * under the terms of the GNU General Public License version 2 only, as
007 * published by the Free Software Foundation.
008 *
009 * This code is distributed in the hope that it will be useful, but WITHOUT
010 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
011 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
012 * version 2 for more details (a copy is included in the LICENSE file that
013 * accompanied this code).
014 *
015 * You should have received a copy of the GNU General Public License version
016 * 2 along with this work; if not, write to the Free Software Foundation,
017 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
018 *
019 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
020 * or visit www.oracle.com if you need additional information or have any
021 * questions.
022 */
023package com.oracle.graal.hotspot.replacements;
024
025import static com.oracle.graal.hotspot.replacements.HotSpotReplacementsUtil.*;
026import static com.oracle.graal.nodes.extended.BranchProbabilityNode.*;
027import com.oracle.graal.api.replacements.*;
028import com.oracle.graal.compiler.common.spi.*;
029
030/**
031 * Substitutions for {@link java.lang.System} methods.
032 */
033@ClassSubstitution(java.lang.System.class)
034public class SystemSubstitutions {
035
036    public static final ForeignCallDescriptor JAVA_TIME_MILLIS = new ForeignCallDescriptor("javaTimeMillis", long.class);
037    public static final ForeignCallDescriptor JAVA_TIME_NANOS = new ForeignCallDescriptor("javaTimeNanos", long.class);
038
039    @MethodSubstitution
040    public static int identityHashCode(Object x) {
041        if (probability(NOT_FREQUENT_PROBABILITY, x == null)) {
042            return 0;
043        }
044
045        return computeHashCode(x);
046    }
047}