jdk/test/hotspot/jtreg/compiler/c2/TestReplaceNarrowPhiWithBottomPhi.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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/**
 * @test
 * @bug 8370200 8374195
 * @requires (os.arch != "ppc64") & (os.arch != "ppc64le")
 * @library /test/lib /
 * @run driver ${test.main.class}
 */

package compiler.c2;

import compiler.lib.ir_framework.*;
import compiler.lib.ir_framework.Test;

public class TestReplaceNarrowPhiWithBottomPhi {
    private int field1;
    private volatile int field2;

    static public void main(String[] args) {
        TestFramework.run();
    }

    @Test
    @IR(counts = { IRNode.PHI, "2" })
    public void test1() {
        int j;
        for (j = 0; j < 10; j++) {

        }
        inlined1(j);

        // Initially, there are 2 memory Phis: one for bottom, one for field1. After loop opts, both
        // Phis have the same inputs and the narrower Phi should be replaced by the bottom Phi.
        for (int i = 1; i < 100; i *= 2) {
            field2 = 42;
        }
    }

    private void inlined1(int j) {
        if (j == 42) {
            field1 = 42;
        }
    }

    @Run(test = "test1")
    private void test1Runner() {
        test1();
        inlined1(42);
    }
}