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/*
* Copyright (c) 2020, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2020, Arm Limited. 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 8242429
* @summary Better implementation for sign extract.
*
* @run main/othervm -XX:-TieredCompilation -XX:CompileCommand=dontinline,compiler.c2.TestSignExtract::signExtract*
* compiler.c2.TestSignExtract
*/
package compiler.c2;
public class TestSignExtract {
private static final long[] LONG_VALUES = {0L, 0xFFFFFFFFL, 0x12L, -1L, -123L, -0x12L, Long.MAX_VALUE, Long.MIN_VALUE};
private static final int[] INT_VALUES = {0, 0x1234, -1, -0x12345678, Integer.MAX_VALUE, Integer.MIN_VALUE};
private static int signExtractInt1(int x) {
return (x >> 1) >>> 31;
}
private static int signExtractInt2(int x) {
return (x >> 32) >>> 31;
}
private static int signExtractInt3(int x) {
return (x >> 31) >>> 31;
}
private static int signExtractInt4(int x) {
return 0 - (x >> 31);
}
private static long signExtractLong1(long x) {
return (x >> 1) >>> 63;
}
private static long signExtractLong2(long x) {
return (x >> 54) >>> 63;
}
private static long signExtractLong3(long x) {
return (x >> 63) >>> 63;
}
private static long signExtractLong4(long x) {
return 0 - (x >> 63);
}
private static int WARMUP = 5000;
public static void main(String[] args) {
for (int i = 0; i < WARMUP; i++) {
for (int e : INT_VALUES) {
// "(A >> n) >>> 31" => "(A >>> 31)"
assert e >>> 31 == signExtractInt1(e);
assert e >>> 31 == signExtractInt2(e);
assert e >>> 31 == signExtractInt3(e);
// "0 - (A >> 31)" => "(A >>> 31)"
assert e >>> 31 == signExtractInt4(e);
}
for (long e : LONG_VALUES) {
// "(A >> n) >>> 63" => "(A >>> 63)"
assert e >>> 63 == signExtractLong1(e);
assert e >>> 63 == signExtractLong2(e);
assert e >>> 63 == signExtractLong3(e);
// "0 - (A >> 63)" => "(A >>> 63)"
assert e >>> 63 == signExtractLong4(e);
}
}
}
}
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