Skip to content

Commit

Permalink
8257182: JCK test failures in integer / long rotation tests
Browse files Browse the repository at this point in the history
Reviewed-by: mdoerr, vlivanov, thartmann, kvn
  • Loading branch information
chhagedorn committed Dec 4, 2020
1 parent f33808f commit 4a85514
Show file tree
Hide file tree
Showing 2 changed files with 94 additions and 8 deletions.
20 changes: 12 additions & 8 deletions src/hotspot/share/opto/mulnode.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -1506,8 +1506,9 @@ const Type* RotateLeftNode::Value(PhaseGVN* phase) const {
return r1;
}
if (r1->is_con() && r2->is_con()) {
int shift = r2->get_con() & (BitsPerJavaInteger - 1); // semantics of Java shifts
return TypeInt::make((r1->get_con() << shift) | (r1->get_con() >> (32 - shift)));
juint r1_con = (juint)r1->get_con();
juint shift = (juint)(r2->get_con()) & (juint)(BitsPerJavaInteger - 1); // semantics of Java shifts
return TypeInt::make((r1_con << shift) | (r1_con >> (32 - shift)));
}
return TypeInt::INT;
} else {
Expand All @@ -1524,8 +1525,9 @@ const Type* RotateLeftNode::Value(PhaseGVN* phase) const {
return r1;
}
if (r1->is_con() && r2->is_con()) {
int shift = r2->get_con() & (BitsPerJavaLong - 1); // semantics of Java shifts
return TypeLong::make((r1->get_con() << shift) | (r1->get_con() >> (64 - shift)));
julong r1_con = (julong)r1->get_con();
julong shift = (julong)(r2->get_con()) & (julong)(BitsPerJavaLong - 1); // semantics of Java shifts
return TypeLong::make((r1_con << shift) | (r1_con >> (64 - shift)));
}
return TypeLong::LONG;
}
Expand Down Expand Up @@ -1583,8 +1585,9 @@ const Type* RotateRightNode::Value(PhaseGVN* phase) const {
return r1;
}
if (r1->is_con() && r2->is_con()) {
int shift = r2->get_con() & (BitsPerJavaInteger - 1); // semantics of Java shifts
return TypeInt::make((r1->get_con() >> shift) | (r1->get_con() << (32 - shift)));
juint r1_con = (juint)r1->get_con();
juint shift = (juint)(r2->get_con()) & (juint)(BitsPerJavaInteger - 1); // semantics of Java shifts
return TypeInt::make((r1_con >> shift) | (r1_con << (32 - shift)));
}
return TypeInt::INT;
} else {
Expand All @@ -1600,8 +1603,9 @@ const Type* RotateRightNode::Value(PhaseGVN* phase) const {
return r1;
}
if (r1->is_con() && r2->is_con()) {
int shift = r2->get_con() & (BitsPerJavaLong - 1); // semantics of Java shifts
return TypeLong::make((r1->get_con() >> shift) | (r1->get_con() << (64 - shift)));
julong r1_con = (julong)r1->get_con();
julong shift = (julong)(r2->get_con()) & (julong)(BitsPerJavaLong - 1); // semantics of Java shifts
return TypeLong::make((r1_con >> shift) | (r1_con << (64 - shift)));
}
return TypeLong::LONG;
}
Expand Down
82 changes: 82 additions & 0 deletions test/hotspot/jtreg/compiler/c2/TestRotateNegativeEvenValues.java
Original file line number Diff line number Diff line change
@@ -0,0 +1,82 @@
/*
* 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 8257182
* @requires vm.compiler2.enabled
* @summary Test RotateLeftNode and RotateRightNode with negative even numbers which produces a wrong result due to
* applying an arithemtic instead of a logical shift.
* @run main/othervm -XX:CompileCommand=compileonly,compiler.c2.TestRotateNegativeEvenValues::run
* -XX:CompileCommand=inline,compiler.c2.TestRotateNegativeEvenValues::test
* -Xcomp -XX:-TieredCompilation compiler.c2.TestRotateNegativeEvenValues
*/
package compiler.c2;

public class TestRotateNegativeEvenValues {

public static void run() {
test(1 << 31); // INT_MIN
test(1L << 63); // LONG_MIN
test(-1 << 10); // -1024
test(-1L << 10); // -1024
test(-1 << 20); // -1048576
test(-1L << 20); // -1048576
test(-2); // 111...10
test(-2L); // 111...10
test(-3546); // Random minus even number
test(-3546L); // Random minus even number
}

// Inlined such that negativeEvenNumber is a constant
public static void test(int negativeEvenNumber) {
for (int i = 1; i <= 1; i++) {
int leftShift = negativeEvenNumber << -i;
int rightShift = negativeEvenNumber >>> i;
if ((leftShift | rightShift) != (rightShift | leftShift)) {
int or1 = leftShift | rightShift;
int or2 = rightShift | leftShift;
throw new RuntimeException("Or operations are not equal:" + " " + or1 + " vs. "+ or2
+ " - leftShift: " + leftShift + ", rightShift: " + rightShift);
}
}
}

// Inlined such that negativeEvenNumber is a constant
public static void test(long negativeEvenNumber) {
for (int i = 1; i <= 1; i++) {
long leftShift = negativeEvenNumber << -i;
long rightShift = negativeEvenNumber >>> i;
if ((leftShift | rightShift) != (rightShift | leftShift)) {
long or1 = leftShift | rightShift;
long or2 = rightShift | leftShift;
throw new RuntimeException("Or operations are not equal:" + " " + or1 + " vs. "+ or2
+ " - leftShift: " + leftShift + ", rightShift: " + rightShift);
}
}
}

public static void main(String argv[]) {
run();
}
}

1 comment on commit 4a85514

@openjdk-notifier
Copy link

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Please sign in to comment.