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

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 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

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/*

 * @test

 * @summary tests on constant folding of unsafe get operations

 * @library /testlibrary /test/lib

 *

 * @run main/bootclasspath -XX:+UnlockDiagnosticVMOptions

 *                   -Xbatch -XX:-TieredCompilation

 *                   -XX:+FoldStableValues

 *                   UnsafeGetStableArrayElement

 *

 * @run main/bootclasspath -XX:+UnlockDiagnosticVMOptions

 *                   -Xbatch -XX:+TieredCompilation -XX:TieredStopAtLevel=1

 *                   -XX:+FoldStableValues

 *                   UnsafeGetStableArrayElement

 */

import jdk.internal.misc.Unsafe;

import jdk.internal.vm.annotation.Stable;

import java.util.concurrent.Callable;

import static jdk.internal.misc.Unsafe.*;

import static jdk.test.lib.Asserts.*;

public class UnsafeGetStableArrayElement {

    @Stable static final byte[] STABLE_BYTE_ARRAY = new byte[] { 0, 1, -128, 127};

    static final Unsafe U = Unsafe.getUnsafe();

    static int testChar() {

        return U.getChar(STABLE_BYTE_ARRAY, ARRAY_BYTE_BASE_OFFSET + 0 * ARRAY_CHAR_INDEX_SCALE) +

               U.getChar(STABLE_BYTE_ARRAY, ARRAY_BYTE_BASE_OFFSET + 1 * ARRAY_CHAR_INDEX_SCALE);

    }

    static void run(Callable c) throws Exception {

        Object first = c.call();

        for (int i = 0; i < 20_000; i++) {

            assertEQ(first, c.call());

        }

    }

    public static void main(String[] args) throws Exception {

        run(UnsafeGetStableArrayElement::testChar);

    }

}