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/*
* Copyright (c) 2024, 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.
*/
/*
* @test
* @bug 8316756
* @summary Test UNSAFE.copyMemory in combination with Escape Analysis
* @library /test/lib
*
* @modules java.base/jdk.internal.misc
*
* @run main/othervm -XX:-TieredCompilation -Xbatch -XX:CompileCommand=quiet -XX:CompileCommand=compileonly,compiler.unsafe.UnsafeArrayCopy::test*
* compiler.unsafe.UnsafeArrayCopy
*/
package compiler.unsafe;
import java.lang.reflect.*;
import java.util.*;
import jdk.internal.misc.Unsafe;
public class UnsafeArrayCopy {
private static Unsafe UNSAFE = Unsafe.getUnsafe();
static long SRC_BASE = UNSAFE.allocateMemory(4);
static long DST_BASE = UNSAFE.allocateMemory(4);
static class MyClass {
int x;
}
static int test() {
MyClass obj = new MyClass(); // Non-escaping to trigger Escape Analysis
UNSAFE.copyMemory(null, SRC_BASE, null, DST_BASE, 4);
obj.x = 42;
return obj.x;
}
static int[] test2() {
int[] src = new int[4];
int[] dst = new int[4];
MyClass obj = new MyClass();
UNSAFE.copyMemory(src, 0, dst, 0, 4);
obj.x = 42;
dst[1] = obj.x;
return dst;
}
public static void main(String[] args) {
for (int i = 0; i < 50_000; ++i) {
test();
test2();
}
}
}
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