src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.core.test/src/org/graalvm/compiler/core/test/ConditionalEliminationTest15.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package org.graalvm.compiler.core.test;

import org.graalvm.compiler.debug.DebugContext;
import org.graalvm.compiler.graph.Node;
import org.graalvm.compiler.nodes.StructuredGraph;
import org.graalvm.compiler.nodes.StructuredGraph.AllowAssumptions;
import org.graalvm.compiler.nodes.calc.IntegerLessThanNode;
import org.graalvm.compiler.nodes.spi.LoweringTool;
import org.graalvm.compiler.phases.common.CanonicalizerPhase;
import org.graalvm.compiler.phases.common.IterativeConditionalEliminationPhase;
import org.graalvm.compiler.phases.common.LoweringPhase;
import org.graalvm.compiler.phases.tiers.PhaseContext;
import org.graalvm.compiler.virtual.phases.ea.EarlyReadEliminationPhase;
import org.junit.Assert;
import org.junit.Test;

/**
 * Collection of tests for {@link org.graalvm.compiler.phases.common.ConditionalEliminationPhase}
 * including those that triggered bugs in this phase.
 */
public class ConditionalEliminationTest15 extends ConditionalEliminationTestBase {

    private void checkNodeCount(String methodName, Class<? extends Node> nodeClass, int count) {
        StructuredGraph graph = parseEager(methodName, AllowAssumptions.YES);

        CanonicalizerPhase canonicalizer = new CanonicalizerPhase();
        PhaseContext context = new PhaseContext(getProviders());

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

        // Merge arr.length reads.
        new EarlyReadEliminationPhase(canonicalizer).apply(graph, context);
        new IterativeConditionalEliminationPhase(canonicalizer, true).apply(graph, context);

        getDebugContext().dump(DebugContext.BASIC_LEVEL, graph, "After ConditionalEliminationPhase");

        Assert.assertEquals(count, graph.getNodes().filter(nodeClass).count());
    }

    public static int testRedundantIntegerLessThanNode(int index, int[] arr) {
        while (arr[index] != 42) {
            if (index >= 0) { // redundant
                return 1;
            }
        }
        return 2;
    }

    public static int testRedundantIntegerLessThanNode2(int index, int[] arr) {
        while (arr[index] != 42) {
            if (index < arr.length) { // redundant
                return 1;
            }
        }
        return 2;
    }

    @Test
    public void testRedundantSignedLessThanNode() {
        checkNodeCount("testRedundantIntegerLessThanNode", IntegerLessThanNode.class, 0);
        checkNodeCount("testRedundantIntegerLessThanNode2", IntegerLessThanNode.class, 0);
    }
}