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 * version 2 for more details (a copy is included in the LICENSE file that

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 *

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package org.graalvm.compiler.core.test;

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

import org.graalvm.compiler.nodes.StructuredGraph;

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

import org.graalvm.compiler.nodes.extended.UnsafeAccessNode;

import org.graalvm.compiler.nodes.memory.ReadNode;

import org.graalvm.compiler.nodes.memory.WriteNode;

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

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

import org.graalvm.compiler.options.OptionValues;

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

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

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

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

import org.junit.Assert;

import org.junit.Test;

import sun.misc.Unsafe;

public class UnsafeReadEliminationTest extends GraalCompilerTest {

    public static long[] Memory = new long[]{1, 2};

    public static double SideEffectD;

    public static double SideEffectL;

    private static final long booleanArrayBaseOffset;

    private static final long byteArrayBaseOffset;

    private static final long intArrayBaseOffset;

    private static final long longArrayBaseOffset;

    static {

        booleanArrayBaseOffset = UNSAFE.arrayBaseOffset(boolean[].class);

        byteArrayBaseOffset = UNSAFE.arrayBaseOffset(byte[].class);

        intArrayBaseOffset = UNSAFE.arrayBaseOffset(int[].class);

        longArrayBaseOffset = UNSAFE.arrayBaseOffset(long[].class);

    }

    private static final long ARRAY_LONG_BASE_OFFSET = Unsafe.ARRAY_LONG_BASE_OFFSET;

    public static long test1Snippet(double a) {

        final Object m = Memory;

        if (a > 0) {

            UNSAFE.putDouble(m, ARRAY_LONG_BASE_OFFSET, a);

        } else {

            SideEffectL = UNSAFE.getLong(m, ARRAY_LONG_BASE_OFFSET);

        }

        return UNSAFE.getLong(m, ARRAY_LONG_BASE_OFFSET);

    }

    public static class A {

        long[][] o;

        long[][] p;

    }

    public static Object test2Snippet(A a, int c) {

        Object phi = null;

        if (c != 0) {

            long[][] r = a.o;

            phi = r;

            UNSAFE.putDouble(r, ARRAY_LONG_BASE_OFFSET, 12d);

        } else {

            long[][] r = a.p;

            phi = r;

            UNSAFE.putLong(r, ARRAY_LONG_BASE_OFFSET, 123);

        }

        GraalDirectives.controlFlowAnchor();

        SideEffectD = UNSAFE.getDouble(phi, ARRAY_LONG_BASE_OFFSET);

        return phi;

    }

    @Test

    public void test01() {

        StructuredGraph graph = parseEager("test1Snippet", AllowAssumptions.NO);

        testEarlyReadElimination(graph, 3, 2);

    }

    @Test

    public void test02() {

        StructuredGraph graph = parseEager("test1Snippet", AllowAssumptions.NO);

        testPartialEscapeReadElimination(graph, 3, 2);

    }

    @Test

    public void test03() {

        StructuredGraph graph = parseEager("test2Snippet", AllowAssumptions.NO);

        testEarlyReadElimination(graph, 3, 3);

    }

    @Test

    public void test04() {

        StructuredGraph graph = parseEager("test2Snippet", AllowAssumptions.NO);

        testEarlyReadElimination(graph, 3, 3);

    }

    public void testEarlyReadElimination(StructuredGraph graph, int reads, int writes) {

        CoreProviders context = getDefaultHighTierContext();

        CanonicalizerPhase canonicalizer = new CanonicalizerPhase();

        canonicalizer.apply(graph, context);

        new EarlyReadEliminationPhase(canonicalizer).apply(graph, context);

        Assert.assertEquals(3, graph.getNodes().filter(UnsafeAccessNode.class).count());

        // after lowering the same applies for reads and writes

        new LoweringPhase(canonicalizer, LoweringTool.StandardLoweringStage.HIGH_TIER).apply(graph, context);

        canonicalizer.apply(graph, context);

        new EarlyReadEliminationPhase(canonicalizer).apply(graph, context);

        Assert.assertEquals(reads, graph.getNodes().filter(ReadNode.class).count());

        Assert.assertEquals(writes, graph.getNodes().filter(WriteNode.class).count());

    }

    public void testPartialEscapeReadElimination(StructuredGraph graph, int reads, int writes) {

        OptionValues options = graph.getOptions();

        CoreProviders context = getDefaultHighTierContext();

        CanonicalizerPhase canonicalizer = new CanonicalizerPhase();

        canonicalizer.apply(graph, context);

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

        Assert.assertEquals(3, graph.getNodes().filter(UnsafeAccessNode.class).count());

        // after lowering the same applies for reads and writes

        new LoweringPhase(canonicalizer, LoweringTool.StandardLoweringStage.HIGH_TIER).apply(graph, context);

        canonicalizer.apply(graph, context);

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

        Assert.assertEquals(reads, graph.getNodes().filter(ReadNode.class).count());

        Assert.assertEquals(writes, graph.getNodes().filter(WriteNode.class).count());

    }

    public static int testWriteIntToByteArraySnippet() {

        byte[] array = new byte[4];

        UNSAFE.putInt(array, byteArrayBaseOffset, 0x01020304);

        return array[0];

    }

    @Test

    public void testWriteIntToByteArray() {

        test("testWriteIntToByteArraySnippet");

    }

    public static byte testWriteSignedExtendedByteToByteArraySnippet(byte b) {

        byte[] array = new byte[4];

        array[0] = 0x01;

        array[1] = 0x02;

        array[2] = 0x03;

        array[3] = 0x04;

        UNSAFE.putInt(array, byteArrayBaseOffset, b);

        return array[3];

    }

    @Test

    public void testWriteSignedExtendedByteToByteArray() {

        test("testWriteSignedExtendedByteToByteArraySnippet", (byte) 0);

    }

    public static int testWriteLongToIntArraySnippet() {

        int[] array = new int[2];

        UNSAFE.putLong(array, intArrayBaseOffset, 0x0102030405060708L);

        return array[0];

    }

    @Test

    public void testWriteLongToIntArray() {

        test("testWriteLongToIntArraySnippet");

    }

    public static int testWriteByteToIntArraySnippet() {

        int[] array = new int[1];

        array[0] = 0x01020304;

        UNSAFE.putByte(array, intArrayBaseOffset, (byte) 0x05);

        return array[0];

    }

    @Test

    public void testWriteByteToIntArray() {

        test("testWriteByteToIntArraySnippet");

    }

    public static long testWriteIntToLongArraySnippet() {

        long[] array = new long[1];

        array[0] = 0x0102030405060708L;

        UNSAFE.putInt(array, longArrayBaseOffset, 0x04030201);

        return array[0];

    }

    @Test

    public void testWriteIntToLongArray() {

        test("testWriteIntToLongArraySnippet");

    }

    public static float testWriteFloatToIntArraySnippet() {

        float[] array = new float[1];

        UNSAFE.putInt(array, intArrayBaseOffset, Float.floatToRawIntBits(0.5f));

        return array[0];

    }

    @Test

    public void testWriteFloatToIntArray() {

        test("testWriteFloatToIntArraySnippet");

    }

    public static final byte[] FINAL_BYTE_ARRAY = new byte[16];

    public static boolean alignedKill() {

        int beforeKill = UNSAFE.getInt(FINAL_BYTE_ARRAY, byteArrayBaseOffset);

        FINAL_BYTE_ARRAY[0] = 1;

        int afterKill = UNSAFE.getInt(FINAL_BYTE_ARRAY, byteArrayBaseOffset);

        FINAL_BYTE_ARRAY[0] = 0; // reset

        return beforeKill == afterKill;

    }

    @Test

    public void testAlignedKill() {

        test("alignedKill");

    }

    public static boolean unalignedKill() {

        int beforeKill = UNSAFE.getInt(FINAL_BYTE_ARRAY, byteArrayBaseOffset);

        FINAL_BYTE_ARRAY[1] = 1;

        int afterKill = UNSAFE.getInt(FINAL_BYTE_ARRAY, byteArrayBaseOffset);

        FINAL_BYTE_ARRAY[1] = 0; // reset

        return beforeKill == afterKill;

    }

    @Test

    public void testUnalignedKill() {

        test("unalignedKill");

    }

    public static final boolean[] FINAL_BOOLEAN_ARRAY = new boolean[16];

    public static boolean killBooleanAccessToBooleanArrayViaBASTORE() {

        boolean beforeKill = UNSAFE.getBoolean(FINAL_BOOLEAN_ARRAY, booleanArrayBaseOffset);

        FINAL_BOOLEAN_ARRAY[0] = true;

        boolean afterKill = UNSAFE.getBoolean(FINAL_BOOLEAN_ARRAY, booleanArrayBaseOffset);

        FINAL_BOOLEAN_ARRAY[0] = false; // reset

        return beforeKill == afterKill;

    }

    @Test

    public void testKillBooleanAccessToBooleanArrayViaBASTORE() {

        test("killBooleanAccessToBooleanArrayViaBASTORE");

    }

    public static boolean killByteAccessToBooleanArrayViaBASTORE() {

        byte beforeKill = UNSAFE.getByte(FINAL_BOOLEAN_ARRAY, booleanArrayBaseOffset);

        FINAL_BOOLEAN_ARRAY[0] = true;

        byte afterKill = UNSAFE.getByte(FINAL_BOOLEAN_ARRAY, booleanArrayBaseOffset);

        FINAL_BOOLEAN_ARRAY[0] = false; // reset

        return beforeKill == afterKill;

    }

    @Test

    public void testKillByteAccessToBooleanArrayViaBASTORE() {

        test("killByteAccessToBooleanArrayViaBASTORE");

    }

    public static boolean unsafeWriteToBooleanArray() {

        UNSAFE.putByte(FINAL_BOOLEAN_ARRAY, booleanArrayBaseOffset, (byte) 2);

        boolean result = UNSAFE.getBoolean(FINAL_BOOLEAN_ARRAY, booleanArrayBaseOffset);

        FINAL_BOOLEAN_ARRAY[0] = false; // reset

        return result;

    }

    @Test

    public void testUnsafeWriteToBooleanArray() {

        test("unsafeWriteToBooleanArray");

    }

}