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 * 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.

 *

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package org.graalvm.compiler.replacements.test;

import java.util.Objects;

import org.graalvm.compiler.api.directives.GraalDirectives;

import org.graalvm.compiler.nodes.StructuredGraph;

import org.graalvm.compiler.nodes.ValueNode;

import org.graalvm.compiler.nodes.graphbuilderconf.GraphBuilderContext;

import org.graalvm.compiler.nodes.graphbuilderconf.InvocationPlugin;

import org.graalvm.compiler.nodes.graphbuilderconf.InvocationPlugins.Registration;

import org.graalvm.compiler.replacements.Snippets;

import org.graalvm.compiler.replacements.classfile.ClassfileBytecodeProvider;

import org.graalvm.compiler.word.Word;

import jdk.vm.ci.meta.ResolvedJavaMethod;

/**

 * Tests for derived oops in reference maps.

 */

public class DerivedOopTest extends ReplacementsTest implements Snippets {

    private static class Pointers {

        public long basePointer;

        public long internalPointer;

        public long delta() {

            return internalPointer - basePointer;

        }

        @Override

        public boolean equals(Object obj) {

            if (!(obj instanceof Pointers)) {

                return false;

            }

            Pointers other = (Pointers) obj;

            return this.delta() == other.delta();

        }

        @Override

        public int hashCode() {

            return (int) delta();

        }

    }

    private static class Result {

        public Pointers beforeGC;

        public Pointers afterGC;

        Result() {

            beforeGC = new Pointers();

            afterGC = new Pointers();

        }

        @Override

        public int hashCode() {

            final int prime = 31;

            int result = 1;

            result = prime * result + ((afterGC == null) ? 0 : afterGC.hashCode());

            result = prime * result + ((beforeGC == null) ? 0 : beforeGC.hashCode());

            return result;

        }

        @Override

        public boolean equals(Object obj) {

            if (!(obj instanceof Result)) {

                return false;

            }

            Result other = (Result) obj;

            return Objects.equals(this.beforeGC, other.beforeGC) && Objects.equals(this.afterGC, other.afterGC);

        }

    }

    @Test

    public void testFieldOffset() {

        // Run a couple times to encourage objects to move

        for (int i = 0; i < 4; i++) {

            Result r = new Result();

            test("fieldOffsetSnippet", r, 16L);

            Assert.assertEquals(r.beforeGC.delta(), r.afterGC.delta());

        }

    }

    static long getRawPointer(Object obj) {

        // fake implementation for interpreter

        return obj.hashCode();

    }

    static long getRawPointerIntrinsic(Object obj) {

        return Word.objectToTrackedPointer(obj).rawValue();

    }

    public static Result fieldOffsetSnippet(Result obj, long offset) {

        long internalPointer = getRawPointer(obj) + offset;

        // make sure the internal pointer is computed before the safepoint

        GraalDirectives.blackhole(internalPointer);

        obj.beforeGC.basePointer = getRawPointer(obj);

        obj.beforeGC.internalPointer = internalPointer;

        System.gc();

        obj.afterGC.basePointer = getRawPointer(obj);

        obj.afterGC.internalPointer = internalPointer;

        return obj;

    }

    @Override

        ClassfileBytecodeProvider bytecodeProvider = getSystemClassLoaderBytecodeProvider();

        ResolvedJavaMethod intrinsic = getResolvedJavaMethod("getRawPointerIntrinsic");

        r.register1("getRawPointer", Object.class, new InvocationPlugin() {

            @Override

            public boolean apply(GraphBuilderContext b, ResolvedJavaMethod targetMethod, Receiver receiver, ValueNode arg) {

                return b.intrinsify(bytecodeProvider, targetMethod, intrinsic, receiver, new ValueNode[]{arg});

            }

        });

    }

    @Override

    protected boolean checkHighTierGraph(StructuredGraph graph) {

        assert graph.getNodes().filter(WordCastNode.class).count() > 0 : "DerivedOopTest.toLong should be intrinsified";

        return super.checkHighTierGraph(graph);

    }

}