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8329726: Use non-short forward jumps in lightweight locking

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Reviewed-by: shade, kvn, aboldtch
This commit is contained in:
Roman Kennke 2024-04-09 14:50:41 +00:00
parent e75e1cb02c
commit 2e925f263d
2 changed files with 45 additions and 4 deletions
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11
src/hotspot/cpu/x86/c2_MacroAssembler_x86.cpp
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@ -1022,15 +1022,18 @@ void C2_MacroAssembler::fast_lock_lightweight(Register obj, Register box, Regist
#ifdef ASSERT
// Check that locked label is reached with ZF set.
Label zf_correct;
jccb(Assembler::zero, zf_correct);
stop("Fast Lock ZF != 1");
Label zf_bad_zero;
jcc(Assembler::zero, zf_correct);
jmp(zf_bad_zero);
#endif
bind(slow_path);
#ifdef ASSERT
// Check that slow_path label is reached with ZF not set.
jccb(Assembler::notZero, zf_correct);
jcc(Assembler::notZero, zf_correct);
stop("Fast Lock ZF != 0");
bind(zf_bad_zero);
stop("Fast Lock ZF != 1");
bind(zf_correct);
#endif
// C2 uses the value of ZF to determine the continuation.
@ -1161,7 +1164,7 @@ void C2_MacroAssembler::fast_unlock_lightweight(Register obj, Register reg_rax,
#ifdef ASSERT
// Check that unlocked label is reached with ZF set.
Label zf_correct;
jccb(Assembler::zero, zf_correct);
jcc(Assembler::zero, zf_correct);
stop("Fast Unlock ZF != 1");
#endif

38
test/hotspot/jtreg/compiler/c2/TestLWLockingCodeGen.java Normal file
View File

@ -0,0 +1,38 @@
/*
* Copyright Amazon.com Inc. 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
* @summary Tests correct code generation of lightweight locking when using -XX:+ShowMessageBoxOnError; times-out on failure
* @bug 8329726
* @run main/othervm -XX:+ShowMessageBoxOnError -Xcomp -XX:-TieredCompilation -XX:CompileOnly=TestLWLockingCodeGen::sync TestLWLockingCodeGen
*/
public class TestLWLockingCodeGen {
private static int val = 0;
public static void main(String[] args) {
sync();
}
private static synchronized void sync() {
val = val + (int)(Math.random() * 42);
}
}