AOTGraalHotSpotVMConfig.java revision 12968:4d8a004e5c6d 
1/*
2 * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
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22 */
23package org.graalvm.compiler.hotspot;
24
25import org.graalvm.compiler.core.common.CompressEncoding;
26
27import jdk.vm.ci.hotspot.HotSpotVMConfigStore;
28
29public class AOTGraalHotSpotVMConfig extends GraalHotSpotVMConfig {
30    private final CompressEncoding aotOopEncoding;
31    private final CompressEncoding aotKlassEncoding;
32
33    public AOTGraalHotSpotVMConfig(HotSpotVMConfigStore store) {
34        super(store);
35        // AOT captures VM settings during compilation. For compressed oops this
36        // presents a problem for the case when the VM selects a zero-shift mode
37        // (i.e., when the heap is less than 4G). Compiling an AOT binary with
38        // zero-shift limits its usability. As such we force the shift to be
39        // always equal to alignment to avoid emitting zero-shift AOT code.
40        CompressEncoding vmOopEncoding = super.getOopEncoding();
41        aotOopEncoding = new CompressEncoding(vmOopEncoding.getBase(), logMinObjAlignment());
42        CompressEncoding vmKlassEncoding = super.getKlassEncoding();
43        aotKlassEncoding = new CompressEncoding(vmKlassEncoding.getBase(), logKlassAlignment);
44        assert check();
45    }
46
47    @Override
48    public CompressEncoding getOopEncoding() {
49        return aotOopEncoding;
50    }
51
52    @Override
53    public CompressEncoding getKlassEncoding() {
54        return aotKlassEncoding;
55    }
56}
57