1 /*
   2  * Copyright (c) 2012, 2018, 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 
  24 
  25 package org.graalvm.compiler.replacements;
  26 
  27 import java.util.ArrayList;
  28 import java.util.Collections;
  29 import java.util.List;
  30 
  31 import org.graalvm.compiler.core.common.GraalOptions;
  32 
  33 /**
  34  * A counter that can (only) be {@linkplain #inc() incremented} from within a snippet for gathering
  35  * snippet specific metrics.
  36  */
  37 public final class SnippetCounter implements Comparable<SnippetCounter> {
  38     /**
  39      * A group of related counters.
  40      */
  41     public static class Group {
  42 
  43         public interface Factory {
  44             /**
  45              * If snippet counters are {@linkplain GraalOptions#SnippetCounters enabled}, creates
  46              * and registers a {@link Group} with the given name. Otherwise, returns null.
  47              *
  48              * @param name name of the counter group
  49              */
  50             Group createSnippetCounterGroup(String name);
  51         }
  52 
  53         public static final Factory NullFactory = new Factory() {
  54 
  55             @Override
  56             public Group createSnippetCounterGroup(String name) {
  57                 return null;
  58             }
  59         };
  60 
  61         final String name;
  62         final List<SnippetCounter> counters;
  63 
  64         public Group(String name) {
  65             this.name = name;
  66             this.counters = new ArrayList<>();
  67         }
  68 
  69         @Override
  70         public synchronized String toString() {
  71             Collections.sort(counters);
  72 
  73             long total = 0;
  74             int maxNameLen = 0;
  75             for (SnippetCounter c : counters) {
  76                 total += c.value;
  77                 maxNameLen = Math.max(c.name.length(), maxNameLen);
  78             }
  79 
  80             StringBuilder buf = new StringBuilder(String.format("Counters: %s%n", name));
  81 
  82             String formatString = "  %" + maxNameLen + "s: %6.2f%%%," + (String.format("%,d", total).length() + 2) + "d  // %s%n";
  83             for (SnippetCounter c : counters) {
  84                 double percent = total == 0D ? 0D : ((double) (c.value * 100)) / total;
  85                 buf.append(String.format(formatString, c.name, percent, c.value, c.description));
  86             }
  87             buf.append(String.format(formatString, "TOTAL", 100.0D, total, ""));
  88 
  89             return buf.toString();
  90         }
  91     }
  92 
  93     /**
  94      * Sorts counters in descending order of their {@linkplain #value() values}.
  95      */
  96     @Override
  97     public int compareTo(SnippetCounter o) {
  98         return Long.signum(o.value - value);
  99     }
 100 
 101     private final Group group;
 102     private final String name;
 103     private final String description;
 104     private long value;
 105 
 106     /**
 107      * Creates a counter.
 108      *
 109      * @param group the group to which the counter belongs. If this is null, the newly created
 110      *            counter is disabled and {@linkplain #inc() incrementing} is a no-op.
 111      * @param name the name of the counter
 112      * @param description a brief comment describing the metric represented by the counter
 113      */
 114     public SnippetCounter(Group group, String name, String description) {
 115         this.group = group;
 116         this.name = name;
 117         this.description = description;
 118         if (group != null) {
 119             List<SnippetCounter> counters = group.counters;
 120             counters.add(this);
 121         }
 122     }
 123 
 124     public Group getGroup() {
 125         return group;
 126     }
 127 
 128     /**
 129      * Increments the value of this counter. This method can only be used in a snippet on a
 130      * compile-time constant {@link SnippetCounter} object.
 131      */
 132     public void inc() {
 133         if (group != null) {
 134             SnippetCounterNode.increment(this);
 135         }
 136     }
 137 
 138     /**
 139      * Increments the value of this counter. This method can only be used in a snippet on a
 140      * compile-time constant {@link SnippetCounter} object.
 141      */
 142     public void add(int increment) {
 143         if (group != null) {
 144             SnippetCounterNode.add(this, increment);
 145         }
 146     }
 147 
 148     /**
 149      * Gets the value of this counter.
 150      */
 151     public long value() {
 152         return value;
 153     }
 154 
 155     @Override
 156     public String toString() {
 157         if (group != null) {
 158             return "SnippetCounter-" + group.name + ":" + name;
 159         }
 160         return super.toString();
 161     }
 162 }