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

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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.core.test;

import org.graalvm.compiler.nodes.StructuredGraph;

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

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

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

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

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

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

import org.graalvm.compiler.phases.tiers.HighTierContext;

import org.junit.Test;

public class MemoryGraphCanonicalizeTest extends GraalCompilerTest {

    static class TestObject {

        Object object;

        Integer integer;

        int value;

        volatile boolean written;

    }

    public static void simpleElimination(TestObject object) {

        object.object = object;

        object.value = object.integer;

        object.value = object.integer + 2;

        object.value = object.integer + 3;

    }

    @Test

    public void testSimpleElimination() {

        testGraph("simpleElimination", 2);

    }

    public static void complexElimination(TestObject object) {

        object.object = object;

        object.value = object.integer;

        object.value = object.integer + 2;

        if (object.object == null) {

            object.value = object.integer + 3;

        } else {

            object.object = new Object();

        }

        object.written = true;

        object.value = 5;

    }

    @Test

    public void testComplexElimination() {

        testGraph("complexElimination", 6);

    }

    public void testGraph(String name, int expectedWrites) {

        StructuredGraph graph = parseEager(name, StructuredGraph.AllowAssumptions.YES);

        HighTierContext context = getDefaultHighTierContext();

        CanonicalizerPhase canonicalizer = new CanonicalizerPhase();

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

        new IncrementalCanonicalizerPhase<>(canonicalizer, new FloatingReadPhase()).apply(graph, context);

        new CanonicalizerPhase().apply(graph, context);

        int writes = graph.getNodes().filter(WriteNode.class).count();

        assertTrue(writes == expectedWrites, "Expected %d writes, found %d", expectedWrites, writes);

    }

}