1 /*
   2  * Copyright (c) 2015, 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.debug;
  26 
  27 /**
  28  * A helper class for {@link AbstractKey}s that can nest and need to split out accumulated and flat
  29  * values for some kind of counter-like measurement.
  30  */
  31 public abstract class CloseableCounter implements DebugCloseable {
  32 
  33     protected final DebugContext debug;
  34     protected final CloseableCounter parent;
  35     protected final AccumulatedKey counter;
  36     protected final long start;
  37     protected long nestedAmountToSubtract;
  38 
  39     CloseableCounter(DebugContext debug, CloseableCounter parent, AccumulatedKey counter) {
  40         this.debug = debug;
  41         this.parent = parent;
  42         this.start = getCounterValue();
  43         this.counter = counter;
  44     }
  45 
  46     @Override
  47     public DebugContext getDebug() {
  48         return debug;
  49     }
  50 
  51     /**
  52      * A hook for subclasses. Lets them perform custom operations with the value since the last
  53      * invocation of {@link CloseableCounter#close()} of this accumulated
  54      * {@link CloseableCounter#counter}.
  55      *
  56      * @param difference since the last invocation of this counter flat
  57      */
  58     protected void interceptDifferenceAccm(long difference) {
  59         // hook for subclasses
  60     }
  61 
  62     /**
  63      * A hook for subclasses. Lets them perform custom operations with the value since the last
  64      * invocation of {@link CloseableCounter#close()} of this flat {@link CloseableCounter#counter}.
  65      *
  66      * @param difference since the last invocation of this counter flat
  67      */
  68     protected void interceptDifferenceFlat(long difference) {
  69         // hook for subclasses
  70     }
  71 
  72     @Override
  73     public void close() {
  74         long end = getCounterValue();
  75         long difference = end - start;
  76         if (parent != null) {
  77             if (!counter.getName().equals(parent.counter.getName())) {
  78                 parent.nestedAmountToSubtract += difference;
  79                 // Look for our counter in an outer scope and fix up
  80                 // the adjustment to the flat count
  81                 CloseableCounter ancestor = parent.parent;
  82                 while (ancestor != null) {
  83                     if (ancestor.counter.getName().equals(counter.getName())) {
  84                         ancestor.nestedAmountToSubtract -= difference;
  85                         break;
  86                     }
  87                     ancestor = ancestor.parent;
  88                 }
  89             }
  90         }
  91         long flatAmount = difference - nestedAmountToSubtract;
  92         counter.addToCurrentValue(debug, difference);
  93         counter.flat.addToCurrentValue(debug, flatAmount);
  94         interceptDifferenceAccm(difference);
  95         interceptDifferenceFlat(flatAmount);
  96     }
  97 
  98     abstract long getCounterValue();
  99 }