1/*
2 * Copyright (c) 2016, 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
21 * questions.
22 */
23package org.graalvm.compiler.core.common.spi;
24
25import org.graalvm.compiler.options.OptionValues;
26
27import jdk.vm.ci.meta.JavaConstant;
28import jdk.vm.ci.meta.ResolvedJavaField;
29
30/**
31 * Implements the logic that decides whether a field read should be constant folded.
32 */
33public interface ConstantFieldProvider {
34
35    public interface ConstantFieldTool<T> {
36
37        OptionValues getOptions();
38
39        JavaConstant readValue();
40
41        JavaConstant getReceiver();
42
43        T foldConstant(JavaConstant ret);
44
45        T foldStableArray(JavaConstant ret, int stableDimensions, boolean isDefaultStable);
46    }
47
48    /**
49     * Decide whether a read from the {@code field} should be constant folded. This should return
50     * {@link ConstantFieldTool#foldConstant} or {@link ConstantFieldTool#foldStableArray} if the
51     * read should be constant folded, or {@code null} otherwise.
52     */
53    <T> T readConstantField(ResolvedJavaField field, ConstantFieldTool<T> tool);
54}
55