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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

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 *

 * 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,

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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.debug.DebugContext;

import org.graalvm.compiler.debug.DebugContext.Scope;

import org.graalvm.compiler.debug.GraalError;

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;

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 org.graalvm.compiler.word.WordCastNode;

import org.junit.Assert;

import org.junit.Rule;

import org.junit.Test;

import org.junit.rules.ExpectedException;

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;

    }

    @Rule public final ExpectedException thrown = ExpectedException.none();

    private static final String UNKNOWN_REFERENCE_AT_SAFEPOINT_MSG = "should not reach here: unknown reference alive across safepoint";

    @Test

    @SuppressWarnings("try")

    public void testFieldOffsetMergeNonLiveBasePointer() {

        thrown.expect(GraalError.class);

        thrown.expectMessage(UNKNOWN_REFERENCE_AT_SAFEPOINT_MSG);

        DebugContext debug = getDebugContext();

        try (Scope s = debug.disable()) {

            // Run a couple times to encourage objects to move

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

                Result r = new Result();

                test("fieldOffsetMergeSnippet01", r, 8L, 16L);

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

            }

        }

    }

    @Test

    public void testFieldOffsetMergeNonLiveBasePointerNotAccrossSafepoint() {

        // Run a couple times to encourage objects to move

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

            Result r = new Result();

            test("fieldOffsetMergeSnippet02", r, 8L, 16L);

        }

    }

    @Test

    @SuppressWarnings("try")

    public void testFieldOffsetMergeLiveBasePointer() {

        thrown.expect(GraalError.class);

        thrown.expectMessage(UNKNOWN_REFERENCE_AT_SAFEPOINT_MSG);

        DebugContext debug = getDebugContext();

        try (Scope s = debug.disable()) {

            // Run a couple times to encourage objects to move

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

                Result r = new Result();

                test("fieldOffsetMergeSnippet03", r, new Result(), new Result(), 8L, 16L);

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

            }

        }

    }

    public static boolean SideEffectB;

    public static long SideEffect1 = 16;

    public static long SideEffect2 = 16;

    public static Object o1 = new Result();

    public static Object o2 = o1;

    public static Result fieldOffsetMergeSnippet01(Result objResult, long offsetA, long offsetB) {

        long internalPointer;

        if (SideEffectB) {

            internalPointer = getRawPointer(o1) + offsetA;

            SideEffect1 = internalPointer;

        } else {

            internalPointer = getRawPointer(o2) + offsetB;

            SideEffect2 = internalPointer;

        }

        GraalDirectives.controlFlowAnchor();

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

        GraalDirectives.blackhole(internalPointer);

        objResult.beforeGC.basePointer = getRawPointer(objResult);

        objResult.beforeGC.internalPointer = internalPointer;

        System.gc();

        objResult.afterGC.basePointer = getRawPointer(objResult);

        objResult.afterGC.internalPointer = internalPointer;

        return objResult;

    }

    public static Result fieldOffsetMergeSnippet02(Result objResult, long offsetA, long offsetB) {

        long internalPointer;

        if (SideEffectB) {

            internalPointer = getRawPointer(o1) + offsetA;

            SideEffect1 = internalPointer;

        } else {

            internalPointer = getRawPointer(o2) + offsetB;

            SideEffect2 = internalPointer;

        }

        GraalDirectives.controlFlowAnchor();

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

        GraalDirectives.blackhole(internalPointer);

        objResult.beforeGC.basePointer = getRawPointer(objResult);

        objResult.beforeGC.internalPointer = internalPointer;

        objResult.afterGC.basePointer = getRawPointer(objResult);

        objResult.afterGC.internalPointer = internalPointer;

        return objResult;

    }

    public static Result fieldOffsetMergeSnippet03(Result objResult, Result a, Result b, long offsetA, long offsetB) {

        long internalPointer;

        if (SideEffectB) {

            internalPointer = getRawPointer(a) + offsetA;

            SideEffect1 = internalPointer;

        } else {

            internalPointer = getRawPointer(b) + offsetB;

            SideEffect2 = internalPointer;

        }

        GraalDirectives.controlFlowAnchor();

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

        GraalDirectives.blackhole(internalPointer);

        objResult.beforeGC.basePointer = getRawPointer(objResult);

        objResult.beforeGC.internalPointer = internalPointer;

        System.gc();

        objResult.afterGC.basePointer = getRawPointer(objResult);

        objResult.afterGC.internalPointer = internalPointer;

        return objResult;

    }

    @Override

    protected void registerInvocationPlugins(InvocationPlugins invocationPlugins) {

        Registration r = new Registration(invocationPlugins, DerivedOopTest.class);

        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});

            }

        });

        super.registerInvocationPlugins(invocationPlugins);

    }

    @Override

    protected void checkHighTierGraph(StructuredGraph graph) {

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

        super.checkHighTierGraph(graph);

    }

}