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/*
* Copyright (c) 2015, 2016, 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 8078497
* @summary Tests correct alignment of vectors with loop invariant offset.
* @modules java.base/jdk.internal.misc
* @library /test/lib
* @run main compiler.loopopts.superword.TestVectorizationWithInvariant
*/
package compiler.loopopts.superword;
import jdk.internal.misc.Unsafe;
public class TestVectorizationWithInvariant {
private static Unsafe unsafe;
private static final long BYTE_ARRAY_OFFSET;
private static final long CHAR_ARRAY_OFFSET;
static {
unsafe = Unsafe.getUnsafe();
BYTE_ARRAY_OFFSET = unsafe.arrayBaseOffset(byte[].class);
CHAR_ARRAY_OFFSET = unsafe.arrayBaseOffset(char[].class);
}
public static void main(String[] args) throws Exception {
byte[] byte_array1 = new byte[1000];
byte[] byte_array2 = new byte[1000];
char[] char_array = new char[1000];
for (int i = 0; i < 20_000; ++i) {
copyByteToChar(byte_array1, byte_array2, char_array, 1);
copyCharToByte(char_array, byte_array1, 1);
copyCharToByteAligned(char_array, byte_array1);
copyCharToByteUnaligned(char_array, byte_array1);
}
}
/*
* Copy multiple consecutive chars from a byte array to a given offset in a char array
* to trigger C2's superword optimization. The offset in the byte array is independent
* of the loop induction variable and can be set to an arbitrary value. It may then not
* be possible to both align the LoadUS and the StoreC operations. Therefore, vectorization
* should only be done in this case if unaligned memory accesses are allowed.
*/
public static void copyByteToChar(byte[] src1, byte[] src2, char[] dst, int off) {
off = (int) BYTE_ARRAY_OFFSET + (off << 1);
byte[] src = src1;
for (int i = (int) CHAR_ARRAY_OFFSET; i < 100; i = i + 8) {
// Copy 8 chars from src to dst
unsafe.putChar(dst, i + 0, unsafe.getChar(src, off + 0));
unsafe.putChar(dst, i + 2, unsafe.getChar(src, off + 2));
unsafe.putChar(dst, i + 4, unsafe.getChar(src, off + 4));
unsafe.putChar(dst, i + 6, unsafe.getChar(src, off + 6));
unsafe.putChar(dst, i + 8, unsafe.getChar(src, off + 8));
unsafe.putChar(dst, i + 10, unsafe.getChar(src, off + 10));
unsafe.putChar(dst, i + 12, unsafe.getChar(src, off + 12));
unsafe.putChar(dst, i + 14, unsafe.getChar(src, off + 14));
// Prevent loop invariant code motion of char read.
src = (src == src1) ? src2 : src1;
}
}
/*
* Copy multiple consecutive chars from a char array to a given offset in a byte array
* to trigger C2's superword optimization. Checks for similar problems as 'copyByteToChar'.
*/
public static void copyCharToByte(char[] src, byte[] dst, int off) {
off = (int) BYTE_ARRAY_OFFSET + (off << 1);
for (int i = 0; i < 100; i = i + 8) {
// Copy 8 chars from src to dst
unsafe.putChar(dst, off + 0, src[i + 0]);
unsafe.putChar(dst, off + 2, src[i + 1]);
unsafe.putChar(dst, off + 4, src[i + 2]);
unsafe.putChar(dst, off + 6, src[i + 3]);
unsafe.putChar(dst, off + 8, src[i + 4]);
unsafe.putChar(dst, off + 10, src[i + 5]);
unsafe.putChar(dst, off + 12, src[i + 6]);
unsafe.putChar(dst, off + 14, src[i + 7]);
}
}
/*
* Variant of copyCharToByte with a constant destination array offset.
* The loop should always be vectorized because both the LoadUS and StoreC
* operations can be aligned.
*/
public static void copyCharToByteAligned(char[] src, byte[] dst) {
final int off = (int) BYTE_ARRAY_OFFSET;
for (int i = 8; i < 100; i = i + 8) {
// Copy 8 chars from src to dst
unsafe.putChar(dst, off + 0, src[i + 0]);
unsafe.putChar(dst, off + 2, src[i + 1]);
unsafe.putChar(dst, off + 4, src[i + 2]);
unsafe.putChar(dst, off + 6, src[i + 3]);
unsafe.putChar(dst, off + 8, src[i + 4]);
unsafe.putChar(dst, off + 10, src[i + 5]);
unsafe.putChar(dst, off + 12, src[i + 6]);
unsafe.putChar(dst, off + 14, src[i + 7]);
}
}
/*
* Variant of copyCharToByte with a constant destination array offset. The
* loop should only be vectorized if unaligned memory operations are allowed
* because not both the LoadUS and the StoreC can be aligned.
*/
public static void copyCharToByteUnaligned(char[] src, byte[] dst) {
final int off = (int) BYTE_ARRAY_OFFSET + 2;
for (int i = 0; i < 100; i = i + 8) {
// Copy 8 chars from src to dst
unsafe.putChar(dst, off + 0, src[i + 0]);
unsafe.putChar(dst, off + 2, src[i + 1]);
unsafe.putChar(dst, off + 4, src[i + 2]);
unsafe.putChar(dst, off + 6, src[i + 3]);
unsafe.putChar(dst, off + 8, src[i + 4]);
unsafe.putChar(dst, off + 10, src[i + 5]);
unsafe.putChar(dst, off + 12, src[i + 6]);
unsafe.putChar(dst, off + 14, src[i + 7]);
}
}
}
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