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comparison truffle/com.oracle.truffle.api/src/com/oracle/truffle/api/utilities/CountingConditionProfile.java @ 21951:9c8c0937da41

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Moving all sources into truffle subdirectory
author Jaroslav Tulach <jaroslav.tulach@oracle.com>
date Wed, 17 Jun 2015 10:58:08 +0200
parents graal/com.oracle.truffle.api/src/com/oracle/truffle/api/utilities/CountingConditionProfile.java@b1530a6cce8c
children dc83cc1f94f2
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21950:2a5011c7e641 21951:9c8c0937da41
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 import com.oracle.truffle.api.*;
28 import com.oracle.truffle.api.CompilerDirectives.CompilationFinal;
29
30 /**
31 * Utility class to speculate on conditions to be never true or to be never false. Additionally to
32 * {@link BinaryConditionProfile} this implementation of {@link ConditionProfile} also counts the
33 * number of times the condition was true and false. This information is reported to the underlying
34 * optimization system using {@link CompilerDirectives#injectBranchProbability(double, boolean)}.
35 * Condition profiles are intended to be used as part of if conditions.
36 *
37 * @see ConditionProfile#createCountingProfile()
38 */
39 public final class CountingConditionProfile extends ConditionProfile {
40
41 @CompilationFinal private int trueCount;
42 @CompilationFinal private int falseCount;
43
44 CountingConditionProfile() {
45 /* package protected constructor */
46 }
47
48 @Override
49 public boolean profile(boolean value) {
50 if (value) {
51 if (trueCount == 0) {
52 CompilerDirectives.transferToInterpreterAndInvalidate();
53 }
54 if (CompilerDirectives.inInterpreter()) {
55 trueCount++;
56 }
57 } else {
58 if (falseCount == 0) {
59 CompilerDirectives.transferToInterpreterAndInvalidate();
60 }
61 if (CompilerDirectives.inInterpreter()) {
62 falseCount++;
63 }
64 }
65 return CompilerDirectives.injectBranchProbability((double) trueCount / (double) (trueCount + falseCount), value);
66 }
67
68 public int getTrueCount() {
69 return trueCount;
70 }
71
72 public int getFalseCount() {
73 return falseCount;
74 }
75
76 @Override
77 public String toString() {
78 return String.format("%s(trueCount=%s, falseCount=%s)@%x", getClass().getSimpleName(), trueCount, falseCount, hashCode());
79 }
80 }