1/*
2 * Copyright (c) 2009, 2015, 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.replacements.nodes;
24
25import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_0;
26import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_0;
27
28import org.graalvm.compiler.api.replacements.Snippet.VarargsParameter;
29import org.graalvm.compiler.core.common.type.Stamp;
30import org.graalvm.compiler.graph.Node;
31import org.graalvm.compiler.graph.NodeClass;
32import org.graalvm.compiler.graph.NodeInputList;
33import org.graalvm.compiler.graph.spi.Canonicalizable;
34import org.graalvm.compiler.graph.spi.CanonicalizerTool;
35import org.graalvm.compiler.nodeinfo.NodeInfo;
36import org.graalvm.compiler.nodes.FixedWithNextNode;
37import org.graalvm.compiler.nodes.ParameterNode;
38import org.graalvm.compiler.nodes.ValueNode;
39
40/**
41 * Implements the semantics of {@link VarargsParameter}.
42 */
43@NodeInfo(cycles = CYCLES_0, size = SIZE_0)
44public final class LoadSnippetVarargParameterNode extends FixedWithNextNode implements Canonicalizable {
45
46    public static final NodeClass<LoadSnippetVarargParameterNode> TYPE = NodeClass.create(LoadSnippetVarargParameterNode.class);
47    @Input ValueNode index;
48
49    @Input NodeInputList<ParameterNode> parameters;
50
51    public LoadSnippetVarargParameterNode(ParameterNode[] locals, ValueNode index, Stamp stamp) {
52        super(TYPE, stamp);
53        this.index = index;
54        this.parameters = new NodeInputList<>(this, locals);
55    }
56
57    @Override
58    public Node canonical(CanonicalizerTool tool) {
59        if (index.isConstant()) {
60            int indexValue = index.asJavaConstant().asInt();
61            if (indexValue < parameters.size()) {
62                return parameters.get(indexValue);
63            }
64        }
65        return this;
66    }
67}
68