Mercurial > hg > graal-jvmci-8
comparison graal/com.oracle.truffle.api/src/com/oracle/truffle/api/utilities/ValueProfile.java @ 17039:1e542561783e
Truffle: new value profiles prototype.
author | Christian Humer <christian.humer@gmail.com> |
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date | Wed, 03 Sep 2014 14:58:53 +0200 |
parents | |
children | 53afdc71b311 |
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17038:3b3e768a2b92 | 17039:1e542561783e |
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1 /* | |
2 * Copyright (c) 2014, 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. Oracle designates this | |
8 * particular file as subject to the "Classpath" exception as provided | |
9 * by Oracle in the LICENSE file that accompanied this code. | |
10 * | |
11 * This code is distributed in the hope that it will be useful, but WITHOUT | |
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
14 * version 2 for more details (a copy is included in the LICENSE file that | |
15 * accompanied this code). | |
16 * | |
17 * You should have received a copy of the GNU General Public License version | |
18 * 2 along with this work; if not, write to the Free Software Foundation, | |
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | |
20 * | |
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA | |
22 * or visit www.oracle.com if you need additional information or have any | |
23 * questions. | |
24 */ | |
25 package com.oracle.truffle.api.utilities; | |
26 | |
27 /** | |
28 * Utility class to speculate on certain properties of values. | |
29 * | |
30 * Example usage: | |
31 * | |
32 * <pre> | |
33 * private final ValueProfile classProfile = ValueProfile.createClassProfile(); | |
34 * | |
35 * return classProfile.profile(value); | |
36 * </pre> | |
37 * | |
38 * All instances of {@code ValueProfile} (and subclasses) must be held in {@code final} fields for | |
39 * compiler optimizations to take effect. | |
40 * | |
41 * @see #createIdentityProfile() | |
42 * @see #createClassProfile() | |
43 */ | |
44 public abstract class ValueProfile { | |
45 | |
46 public abstract <T> T profile(T value); | |
47 | |
48 /** | |
49 * Returns a {@link ValueProfile} that speculates on the exact class of a value. | |
50 */ | |
51 public static ValueProfile createClassProfile() { | |
52 return new ExactClassValueProfile(); | |
53 } | |
54 | |
55 /** | |
56 * Returns a {@link ValueProfile} that speculates on the object identity of a value. | |
57 */ | |
58 public static ValueProfile createIdentityProfile() { | |
59 return new IdentityValueProfile(); | |
60 } | |
61 | |
62 } |