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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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 * 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.core.test;

import java.lang.reflect.Field;

import org.graalvm.compiler.nodes.StructuredGraph;

import org.graalvm.compiler.nodes.StructuredGraph.AllowAssumptions;

import org.graalvm.compiler.nodes.spi.CoreProviders;

import org.graalvm.compiler.options.OptionValues;

import org.graalvm.compiler.phases.common.CanonicalizerPhase;

import org.graalvm.compiler.virtual.phases.ea.PartialEscapePhase;

import org.junit.Test;

import jdk.vm.ci.code.InstalledCode;

import jdk.vm.ci.meta.ResolvedJavaMethod;

public class UnsafeVirtualizationTest extends GraalCompilerTest {

    public static class Base {

        /*

         * This padding ensure that the size of the Base class ends up as a multiple of 8, which

         * makes the first field of the subclass 8-byte aligned.

         */

        double padding;

    }

    public static class A extends Base {

        int f1;

        int f2;

    }

    private static final long AF1Offset;

    private static final long AF2Offset;

    static {

        long o1 = -1;

        long o2 = -1;

        try {

            Field f1 = A.class.getDeclaredField("f1");

            Field f2 = A.class.getDeclaredField("f2");

            o1 = UNSAFE.objectFieldOffset(f1);

            o2 = UNSAFE.objectFieldOffset(f2);

        } catch (NoSuchFieldException | SecurityException e) {

            throw new AssertionError(e);

        }

        AF1Offset = o1;

        AF2Offset = o2;

    }

    public static int unsafeSnippet1(double i1) {

        A a = new A();

        UNSAFE.putDouble(a, AF1Offset, i1);

        return UNSAFE.getInt(a, AF1Offset) + UNSAFE.getInt(a, AF2Offset);

    }

    public static long unsafeSnippet2a(int i1) {

        A a = new A();

        UNSAFE.putDouble(a, AF1Offset, i1);

        a.f1 = i1;

        return UNSAFE.getLong(a, AF1Offset);

    }

    public static long unsafeSnippet2b(int i1) {

        A a = new A();

        UNSAFE.putDouble(a, AF1Offset, i1);

        a.f2 = i1;

        return UNSAFE.getLong(a, AF1Offset);

    }

    public static long unsafeSnippet3a(int i1) {

        A a = new A();

        UNSAFE.putDouble(a, AF1Offset, i1);

        UNSAFE.putInt(a, AF1Offset, i1);

        return UNSAFE.getLong(a, AF1Offset);

    }

    public static long unsafeSnippet3b(int i1) {

        A a = new A();

        UNSAFE.putDouble(a, AF1Offset, i1);

        UNSAFE.putInt(a, AF2Offset, i1);

        return UNSAFE.getLong(a, AF1Offset);

    }

    public static int unsafeSnippet4(double i1) {

        A a = new A();

        UNSAFE.putDouble(a, AF1Offset, i1);

        UNSAFE.putDouble(a, AF1Offset, i1);

        return UNSAFE.getInt(a, AF1Offset) + UNSAFE.getInt(a, AF2Offset);

    }

    @Test

    public void testUnsafePEA01() {

        testPartialEscapeReadElimination("unsafeSnippet1", false, 1.0);

        testPartialEscapeReadElimination("unsafeSnippet1", true, 1.0);

    }

    @Test

    public void testUnsafePEA02() {

        testPartialEscapeReadElimination("unsafeSnippet2a", false, 1);

        testPartialEscapeReadElimination("unsafeSnippet2a", true, 1);

        testPartialEscapeReadElimination("unsafeSnippet2b", false, 1);

        testPartialEscapeReadElimination("unsafeSnippet2b", true, 1);

    }

    @Test

    public void testUnsafePEA03() {

        testPartialEscapeReadElimination("unsafeSnippet3a", false, 1);

        testPartialEscapeReadElimination("unsafeSnippet3a", true, 1);

        testPartialEscapeReadElimination("unsafeSnippet3b", false, 1);

        testPartialEscapeReadElimination("unsafeSnippet3b", true, 1);

    }

    @Test

    public void testUnsafePEA04() {

        testPartialEscapeReadElimination("unsafeSnippet4", false, 1.0);

        testPartialEscapeReadElimination("unsafeSnippet4", true, 1.0);

    }

    public void testPartialEscapeReadElimination(String snippet, boolean canonicalizeBefore, Object... args) {

        assert AF1Offset % 8 == 0 : "First of the two int-fields must be 8-byte aligned";

        ResolvedJavaMethod method = getResolvedJavaMethod(snippet);

        StructuredGraph graph = parseEager(snippet, AllowAssumptions.NO);

        OptionValues options = graph.getOptions();

        CoreProviders context = getDefaultHighTierContext();

        CanonicalizerPhase canonicalizer = new CanonicalizerPhase();

        if (canonicalizeBefore) {

            canonicalizer.apply(graph, context);

        }

        Result r = executeExpected(method, null, args);

        new PartialEscapePhase(true, true, canonicalizer, null, options).apply(graph, context);

        try {

            InstalledCode code = getCode(method, graph);

            Object result = code.executeVarargs(args);

            assertEquals(r, new Result(result, null));

        } catch (Throwable e) {

            assertFalse(true, e.toString());

        }

    }

}