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     // Gettters/Setters/Predicates
  35     // ------------------------------------------------------------------------
  36
  37     public double getValue() {
  38         return value;
  39     }
  40
  41     public void setValue(double val) {
  42         value = val;
  43     }
  44
  45     public FloatDeclaration getDeclaration() {
  46         return declaration;
  47     }
  48
  49     // ------------------------------------------------------------------------
  50     // Operations
  51     // ------------------------------------------------------------------------
  52
  53
  54
  55     @Override
  56     public void read(BitBuffer input) {
  57         int exp = declaration.getExponent();
  58         int mant = declaration.getMantissa();
  59         if( (exp + mant) == 32 ){
  60             value = readRawFloat32(input, mant , exp);
  61         }
  62         else if((exp + mant) == 64)
  63         {
  64             value = readRawFloat64(input, mant,exp);
  65         }
  66         else
  67         {
  68             value = Double.NaN;
  69         }
  70     }
  71
  72
  73
  74     private static double readRawFloat64(BitBuffer input, final int manBits, final int expBits) {
  75        long low = input.getInt(32, false);
  76        low = low & 0x00000000FFFFFFFFL;
  77        long high = input.getInt(32, false);
  78        high = high & 0x00000000FFFFFFFFL;
  79        long temp = (high << 32) | low;
  80        return createFloat(temp, manBits-1, expBits);
  81     }
  82
  83     /**
  84      * @param rawValue
  85      * @param manBits
  86      * @param expBits
  87      */
  88     private static double createFloat(long rawValue, final int manBits, final int expBits) {
  89         long manShift = 1L << (manBits);
  90         long manMask = manShift - 1;
  91         long expMask = (1L << expBits) - 1;
  92
  93         int exp = (int) ((rawValue >> (manBits))&expMask)+1;
  94         long man = (rawValue & manMask);
  95         double expPow = Math.pow(2.0, exp - (1 << (expBits - 1)));
  96         double ret = man * 1.0f;
  97         ret /= manShift;
  98         ret += 1.0;
  99         ret *= expPow;
 100         return ret;
 101     }
 102
 103     private static double readRawFloat32(BitBuffer input, final int manBits,
 104     final int expBits) {
 105         long temp = input.getInt(32, false);
 106         return createFloat(temp, manBits-1, expBits);
 107     }
 108
 109     @Override
 110     public String toString() {
 111         return String.valueOf(value);
 112     }
 113 }