Mercurial > hg > truffle
view test/gc/concurrentMarkSweep/CheckAllocateAndSystemGC.java @ 11825:463f51256c86
AMD64HotSpot: emit jump to IC miss handler directly instead of emitting it inside verfied_entry
for empty methods we emitted something like this if a inline cache is needed:
prefix:
00: < IC check >
...
0b: jne <ic_miss_call>
11: nop
...
verified_entry:
20: ret
ic_miss_call:
21: jmp <entry of runtime function>
when a method is deoptimized, HotSpot patches the verified_entry (0x20) with a
jump to a stub that handles call-sites that has been made non-entrant. since this jump
is 5 bytes long, it will overwrite ic_miss_call and blow up every caller that
calls this method via the unverified entry (prefix).
the fix is to emit the jump to the runtime function inside the unverfied entry:
prefix:
00: < IC check >
...
0b: je <verified_entry>
11: jeq <entry of runtime function>
16: nop
...
verified_entry:
20: ret
author | Bernhard Urban <bernhard.urban@jku.at> |
---|---|
date | Mon, 30 Sep 2013 09:32:18 +0200 |
parents | a9d568b7df60 |
children |
line wrap: on
line source
/* * Copyright (c) 2013, 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 CheckAllocateAndSystemGC * @summary CMS: assert(used() == used_after_gc && used_after_gc <= capacity()) failed: used: 0 used_after_gc: 292080 capacity: 1431699456 * @bug 8013032 * @key gc * @key regression * @library /testlibrary * @run main/othervm CheckAllocateAndSystemGC * @author jon.masamitsu@oracle.com */ import com.oracle.java.testlibrary.*; public class CheckAllocateAndSystemGC { public static void main(String args[]) throws Exception { ProcessBuilder pb = ProcessTools.createJavaProcessBuilder( "-showversion", "-XX:+UseConcMarkSweepGC", "-Xmn4m", "-XX:MaxTenuringThreshold=1", "-XX:-UseCMSCompactAtFullCollection", "CheckAllocateAndSystemGC$AllocateAndSystemGC" ); OutputAnalyzer output = new OutputAnalyzer(pb.start()); output.shouldNotContain("error"); output.shouldHaveExitValue(0); } static class AllocateAndSystemGC { public static void main(String [] args) { Integer x[] = new Integer [1000]; // Allocate enough objects to cause a minor collection. // These allocations suffice for a 4m young geneneration. for (int i = 0; i < 100; i++) { Integer y[] = new Integer[10000]; } System.gc(); } } }