/*

 * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.

 * 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.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package org.graalvm.compiler.core.test;

import org.junit.Test;

import org.graalvm.compiler.nodes.GuardNode;

import org.graalvm.compiler.nodes.StructuredGraph;

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

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

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

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

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

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

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

/**

 * Collection of tests for

 * {@link org.graalvm.compiler.phases.common.DominatorConditionalEliminationPhase} including those

 * that triggered bugs in this phase.

 */

public class ConditionalEliminationTest2 extends ConditionalEliminationTestBase {

    public static Object field;

    static class Entry {

        final String name;

        Entry(String name) {

            this.name = name;

        }

    }

    static class EntryWithNext extends Entry {

        EntryWithNext(String name, Entry next) {

            super(name);

            this.next = next;

        }

        final Entry next;

    }

    public static Entry search(Entry start, String name, Entry alternative) {

        Entry current = start;

        do {

            while (current instanceof EntryWithNext) {

                if (name != null && current.name == name) {

                    current = null;

                } else {

                    Entry next = ((EntryWithNext) current).next;

                    current = next;

                }

            }

            if (current != null) {

                if (current.name.equals(name)) {

                    return current;

                }

            }

            if (current == alternative) {

                return null;

            }

            current = alternative;

        } while (true);

    }

    public static int testRedundantComparesSnippet(int[] array) {

        if (array == null) {

            return 0;

        }

        return array[0] + array[1] + array[2] + array[3];

    }

    @Test

    public void testRedundantCompares() {

        StructuredGraph graph = parseEager("testRedundantComparesSnippet", AllowAssumptions.YES);

        CanonicalizerPhase canonicalizer = new CanonicalizerPhase();

        PhaseContext context = new PhaseContext(getProviders());

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

        canonicalizer.apply(graph, context);

        new FloatingReadPhase().apply(graph);

        new DominatorConditionalEliminationPhase(true).apply(graph, context);

        canonicalizer.apply(graph, context);

        assertDeepEquals(1, graph.getNodes().filter(GuardNode.class).count());

    }

    public static String testInstanceOfCheckCastSnippet(Object e) {

        if (e instanceof Entry) {

            return ((Entry) e).name;

        }

        return null;

    }

    @Test

    public void testInstanceOfCheckCastLowered() {

        StructuredGraph graph = parseEager("testInstanceOfCheckCastSnippet", AllowAssumptions.YES);

        CanonicalizerPhase canonicalizer = new CanonicalizerPhase();

        PhaseContext context = new PhaseContext(getProviders());

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

        canonicalizer.apply(graph, context);

        new DominatorConditionalEliminationPhase(true).apply(graph, context);

        canonicalizer.apply(graph, context);

        assertDeepEquals(0, graph.getNodes().filter(GuardNode.class).count());

    }

}