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/*
* Copyright (c) 2020, 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 8251535
* @summary Tests partial peeling at unsigned tests.
* @library /test/lib /
* @run main/othervm -Xcomp -XX:-TieredCompilation
* -XX:CompileCommand=compileonly,compiler.loopopts.TestPartialPeelAtUnsignedTests::test*
* compiler.loopopts.TestPartialPeelAtUnsignedTests
*/
package compiler.loopopts;
import jdk.test.lib.Asserts;
public class TestPartialPeelAtUnsignedTests {
/*
loop:
i += 1000;
if (i <u 10_000) {
goto exit;
}
goto loop;
exit:
return i;
C2 splits the unsigned loop exit check to have a
signed exit test as cut point for partial peeling:
loop:
i += 1000;
if (i < 10_000) { <-- This exit condition is wrong!
goto exit;
}
if (i <u 10_000) {
goto exit;
}
goto loop;
exit:
return i;
*/
static int test1(int i) {
boolean cond = false;
while (!cond) {
i += 1000;
// Converted to (i <u 10_000)
cond = (0 <= i) && (i < 10_000);
}
return i;
}
/*
Same as test1 but with a negative stride.
loop:
i -= 1000;
if (i <u 10_000) {
goto exit;
}
goto loop;
exit:
return i;
Converted to:
loop:
i -= 1000;
if (i >= 0) { <-- This exit condition is wrong!
goto exit;
}
if (i <u 10_000) {
goto exit;
}
goto loop;
exit:
return i;
*/
static int test2(int i) {
boolean cond = false;
while (!cond) {
i -= 1000;
cond = (0 <= i) && (i < 10_000);
}
return i;
}
/*
Same as test1 but with inverted exit condition.
loop:
i += 1000;
if (i <u 10_000) {
goto loop;
}
goto exit;
exit:
return i;
Converted to:
loop:
i += 1000;
if (!(i < 10_000)) { <-- Correct exit condition.
goto exit;
}
if (i <u 10_000) {
goto loop;
}
goto exit;
exit:
return i;
*/
static int test3(int i) {
boolean cond = true;
while (cond) {
i += 1000;
cond = (0 <= i) && (i < 10_000);
}
return i;
}
/*
Same as test2 but with inverted exit condition.
loop:
i -= 1000;
if (i <u 10_000) {
goto loop;
}
goto exit;
exit:
return i;
Converted to:
loop:
i -= 1000;
if (!(i >= 0)) { <-- Correct exit condition.
goto exit;
}
if (i <u 10_000) {
goto loop;
}
goto exit;
exit:
return i;
*/
static int test4(int i) {
boolean cond = true;
while (cond) {
i -= 1000;
cond = (0 <= i) && (i < 10_000);
}
return i;
}
public static void main(String[] args) {
Asserts.assertEQ(test1(10_000), 704);
Asserts.assertEQ(test2(-10_000), 9296);
Asserts.assertEQ(test3(0), 10000);
Asserts.assertEQ(test4(9999), -1);
}
}
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