1 /*
2 * Copyright (c) 2013, 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 */
23 package jdk.vm.ci.meta;
24
25 /**
26 * This object holds probability information for a set of items that were profiled at a specific
27 * BCI. The precision of the supplied values may vary, but a runtime that provides this information
28 * should be aware that it will be used to guide performance-critical decisions like speculative
29 * inlining, etc.
30 *
31 * @param <T> a subclass of AbstractProfiledItem
32 * @param <U> the class of the items that are profiled at the specific BCI and for which
33 * probabilities are stored. E.g., a ResolvedJavaType or a ResolvedJavaMethod.
34 */
35 public abstract class AbstractJavaProfile<T extends AbstractProfiledItem<U>, U> {
36
37 private final double notRecordedProbability;
38 private final T[] pitems;
39
40 public AbstractJavaProfile(double notRecordedProbability, T[] pitems) {
41 this.pitems = pitems;
42 assert !Double.isNaN(notRecordedProbability);
43 this.notRecordedProbability = notRecordedProbability;
44 assert isSorted();
45 assert totalProbablility() >= 0 && totalProbablility() <= 1.0001 : totalProbablility() + " " + this;
46 }
47
48 private double totalProbablility() {
49 double total = notRecordedProbability;
50 for (T item : pitems) {
51 total += item.probability;
52 }
53 return total;
54 }
55
56 /**
57 * Determines if an array of profiled items are sorted in descending order of their
58 * probabilities.
59 */
60 private boolean isSorted() {
61 for (int i = 1; i < pitems.length; i++) {
62 if (pitems[i - 1].getProbability() < pitems[i].getProbability()) {
63 return false;
64 }
65 }
66 return true;
67 }
68
69 /**
70 * Returns the estimated probability of all types that could not be recorded due to profiling
71 * limitations.
72 *
73 * @return double value ≥ 0.0 and ≤ 1.0
74 */
75 public double getNotRecordedProbability() {
76 return notRecordedProbability;
77 }
78
79 protected T[] getItems() {
80 return pitems;
81 }
82
83 /**
84 * Searches for an entry of a given resolved Java type.
85 *
86 * @param type the type for which an entry should be searched
87 * @return the entry or null if no entry for this type can be found
88 */
89 public T findEntry(ResolvedJavaType type) {
90 if (pitems != null) {
91 for (T pt : pitems) {
92 if (pt.getItem().equals(type)) {
93 return pt;
94 }
95 }
96 }
97 return null;
98 }
99
100 @Override
101 public String toString() {
102 StringBuilder builder = new StringBuilder();
103 builder.append(this.getClass().getName());
104 builder.append("[");
105 if (pitems != null) {
106 for (T pt : pitems) {
107 builder.append(pt.toString());
108 builder.append(", ");
109 }
110 }
111 builder.append(this.notRecordedProbability);
112 builder.append("]");
113 return builder.toString();
114 }
115
116 public boolean isIncluded(U item) {
117 if (this.getNotRecordedProbability() > 0.0) {
118 return true;
119 } else {
120 for (int i = 0; i < getItems().length; i++) {
121 T pitem = getItems()[i];
122 U curType = pitem.getItem();
123 if (curType == item) {
124 return true;
125 }
126 }
127 }
128 return false;
129 }
130
131 @Override
132 public boolean equals(Object obj) {
133 if (obj == this) {
134 return true;
135 }
136 if (!(obj instanceof AbstractJavaProfile)) {
137 return false;
138 }
139 AbstractJavaProfile<?, ?> that = (AbstractJavaProfile<?, ?>) obj;
140 if (that.notRecordedProbability != notRecordedProbability) {
141 return false;
142 }
143 if (that.pitems.length != pitems.length) {
144 return false;
145 }
146 for (int i = 0; i < pitems.length; ++i) {
147 if (!pitems[i].equals(that.pitems[i])) {
148 return false;
149 }
150 }
151 return true;
152 }
153
154 @Override
155 public int hashCode() {
156 return (int) Double.doubleToLongBits(notRecordedProbability) + pitems.length * 13;
157 }
158 }