1/*
2 * Copyright (c) 2015, 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.nodes.cfg;
24
25import java.util.ArrayList;
26import java.util.Arrays;
27import java.util.List;
28
29import org.graalvm.word.LocationIdentity;
30
31public class LocationSet {
32    private LocationIdentity firstLocation;
33    private List<LocationIdentity> list;
34
35    public LocationSet() {
36        list = null;
37    }
38
39    public LocationSet(LocationSet other) {
40        this.firstLocation = other.firstLocation;
41        if (other.list != null && other.list.size() > 0) {
42            list = new ArrayList<>(other.list);
43        }
44    }
45
46    private void initList() {
47        if (list == null) {
48            list = new ArrayList<>(4);
49        }
50    }
51
52    public boolean isEmpty() {
53        return firstLocation == null;
54    }
55
56    public boolean isAny() {
57        return firstLocation != null && firstLocation.isAny();
58    }
59
60    public void add(LocationIdentity location) {
61        if (this.isAny()) {
62            return;
63        } else if (location.isAny()) {
64            firstLocation = location;
65            list = null;
66        } else if (location.isImmutable()) {
67            return;
68        } else {
69            assert location.isMutable() && location.isSingle();
70            if (firstLocation == null) {
71                firstLocation = location;
72            } else if (location.equals(firstLocation)) {
73                return;
74            } else {
75                initList();
76                for (int i = 0; i < list.size(); ++i) {
77                    LocationIdentity value = list.get(i);
78                    if (location.equals(value)) {
79                        return;
80                    }
81                }
82                list.add(location);
83            }
84        }
85    }
86
87    public void addAll(LocationSet other) {
88        if (other.firstLocation != null) {
89            add(other.firstLocation);
90        }
91        List<LocationIdentity> otherList = other.list;
92        if (otherList != null) {
93            for (LocationIdentity l : otherList) {
94                add(l);
95            }
96        }
97    }
98
99    public boolean contains(LocationIdentity locationIdentity) {
100        assert locationIdentity.isSingle();
101        assert locationIdentity.isMutable();
102        if (LocationIdentity.any().equals(firstLocation)) {
103            return true;
104        }
105        if (locationIdentity.equals(firstLocation)) {
106            return true;
107        }
108        if (list != null) {
109            for (int i = 0; i < list.size(); ++i) {
110                LocationIdentity value = list.get(i);
111                if (locationIdentity.equals(value)) {
112                    return true;
113                }
114            }
115        }
116        return false;
117    }
118
119    public List<LocationIdentity> getCopyAsList() {
120        ArrayList<LocationIdentity> result = new ArrayList<>();
121        if (firstLocation != null) {
122            result.add(firstLocation);
123        }
124        if (list != null) {
125            result.addAll(list);
126        }
127        return result;
128    }
129
130    @Override
131    public String toString() {
132        if (this.isAny()) {
133            return "ANY";
134        } else if (this.isEmpty()) {
135            return "EMPTY";
136        } else {
137            List<LocationIdentity> copyAsList = getCopyAsList();
138            return Arrays.toString(copyAsList.toArray(new LocationIdentity[0]));
139        }
140    }
141}
142