org.eclipse.linuxtools.ctf.core/src/org/eclipse/linuxtools/ctf/core/event/types/FloatDefinition.java

   1 /*******************************************************************************
   2  * Copyright (c) 2011-2012 Ericsson, Ecole Polytechnique de Montreal and others
   3  *
   4  * All rights reserved. This program and the accompanying materials are made
   5  * available under the terms of the Eclipse Public License v1.0 which
   6  * accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors: Matthew Khouzam - Initial API and implementation
  10  *******************************************************************************/
  11
  12 package org.eclipse.linuxtools.ctf.core.event.types;
  13
  14 import org.eclipse.linuxtools.internal.ctf.core.event.io.BitBuffer;
  15
  16 public class FloatDefinition extends Definition {
  17     // ------------------------------------------------------------------------
  18     // Attributes
  19     // ------------------------------------------------------------------------
  20
  21     private final FloatDeclaration declaration;
  22     private double value;
  23
  24     // ------------------------------------------------------------------------
  25     // Contructors
  26     // ------------------------------------------------------------------------
  27
  28     public FloatDefinition(FloatDeclaration declaration,
  29             IDefinitionScope definitionScope, String fieldName) {
  30         super(definitionScope, fieldName);
  31         this.declaration = declaration;
  32     }
  33
  34     // ------------------------------------------------------------------------
  35     // Gettters/Setters/Predicates
  36     // ------------------------------------------------------------------------
  37
  38     public double getValue() {
  39         return value;
  40     }
  41
  42     public void setValue(double val) {
  43         value = val;
  44     }
  45
  46     public FloatDeclaration getDeclaration() {
  47         return declaration;
  48     }
  49
  50     // ------------------------------------------------------------------------
  51     // Operations
  52     // ------------------------------------------------------------------------
  53
  54     @Override
  55     public void read(BitBuffer input) {
  56         int exp = declaration.getExponent();
  57         int mant = declaration.getMantissa();
  58         if ((exp + mant) == 32) {
  59             value = readRawFloat32(input, mant, exp);
  60         } else if ((exp + mant) == 64) {
  61             value = readRawFloat64(input, mant, exp);
  62         } else {
  63             value = Double.NaN;
  64         }
  65     }
  66
  67     private static double readRawFloat64(BitBuffer input, final int manBits,
  68             final int expBits) {
  69         long low = input.getInt(32, false);
  70         low = low & 0x00000000FFFFFFFFL;
  71         long high = input.getInt(32, false);
  72         high = high & 0x00000000FFFFFFFFL;
  73         long temp = (high << 32) | low;
  74         return createFloat(temp, manBits - 1, expBits);
  75     }
  76
  77     /**
  78      * @param rawValue
  79      * @param manBits
  80      * @param expBits
  81      */
  82     private static double createFloat(long rawValue, final int manBits,
  83             final int expBits) {
  84         long manShift = 1L << (manBits);
  85         long manMask = manShift - 1;
  86         long expMask = (1L << expBits) - 1;
  87
  88         int exp = (int) ((rawValue >> (manBits)) & expMask) + 1;
  89         long man = (rawValue & manMask);
  90         double expPow = Math.pow(2.0, exp - (1 << (expBits - 1)));
  91         double ret = man * 1.0f;
  92         ret /= manShift;
  93         ret += 1.0;
  94         ret *= expPow;
  95         return ret;
  96     }
  97
  98     private static double readRawFloat32(BitBuffer input, final int manBits,
  99             final int expBits) {
 100         long temp = input.getInt(32, false);
 101         return createFloat(temp, manBits - 1, expBits);
 102     }
 103
 104     @Override
 105     public String toString() {
 106         return String.valueOf(value);
 107     }
 108 }