Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Browse files
Browse the repository at this point in the history
8288445: AArch64: C2 compilation fails with guarantee(!true || (true …
…&& (shift != 0))) failed: impossible encoding Reviewed-by: phh Backport-of: b4490386fe348250e88347526172c1c27ef01eba
- Loading branch information
William Kemper
authored and
Paul Hohensee
committed
Oct 20, 2022
1 parent
5465105
commit a2b2a22
Showing
2 changed files
with
97 additions
and
14 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,73 @@ | ||
| /* | ||
| * Copyright (c) 2022, 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 8288445 | ||
| * @summary Test shift by 0 | ||
| * @run main/othervm -Xbatch -XX:-TieredCompilation | ||
| * compiler.codegen.ShiftByZero | ||
| */ | ||
|
|
||
| package compiler.codegen; | ||
|
|
||
| public class ShiftByZero { | ||
|
|
||
| public static final int N = 64; | ||
|
|
||
| public static int[] i32 = new int[N]; | ||
|
|
||
| public static void bMeth() { | ||
| int shift = i32[0]; | ||
| // This loop is to confuse the optimizer, so that "shift" is | ||
| // optimized to 0 only after loop vectorization. | ||
| for (int i8 = 279; i8 > 1; --i8) { | ||
| shift <<= 6; | ||
| } | ||
| // low 6 bits of shift are 0, so shift can be | ||
| // simplified to constant 0 | ||
| { | ||
| for (int i = 0; i < N; ++i) { | ||
| i32[i] += i32[i] >>= shift; | ||
| } | ||
| for (int i = 0; i < N; ++i) { | ||
| i32[i] += i32[i] >>>= shift; | ||
| } | ||
| for (int i = 0; i < N; ++i) { | ||
| i32[i] >>>= shift; | ||
| } | ||
| for (int i = 0; i < N; ++i) { | ||
| i32[i] >>= shift; | ||
| } | ||
| for (int i = 0; i < N; ++i) { | ||
| i32[i] <<= shift; | ||
| } | ||
| } | ||
| } | ||
|
|
||
| public static void main(String[] strArr) { | ||
| for (int i = 0; i < 20_000; i++) { | ||
| bMeth(); | ||
| } | ||
| } | ||
| } |
a2b2a22There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Review
Issues