BEMTools.cc

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/*
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/*
 * @file BEMTools.cc
 *
 * Implementation of BEMTools class.
 *
 * Created on: 21.1.2016
 * @author Henry Linjamäki 2016 (henry.linjamaki-no.spam-tut.fi)
 * @note rating: red
 */
 
#include "BEMTools.hh"
 
#include <cassert>
 
#include "MathTools.hh"
 
/**
 * Returns bit width required by the encoding and extrabits combination.
 *
 * @note encoding value of zero translates to width of zero.
 */
unsigned
BEMTools::encodingWidth(unsigned encoding, unsigned extrabits) {
    return MathTools::bitLength(encoding) + extrabits;
}
 
/**
 * Calculates the extra bits (zeroes) of the given encoding.
 *
 * For example:
 * @verbatim
 *  (encoding, width) = (3, 5) ->  |00011| -> return 3.
 * @endverbatim
 *
 * @param encoding The encoding value.
 * @param width The number of bits the encoding occupies.
 *              Must be at least or more than required bits needed for the
 *              value. Must greater than 0.
 */
unsigned
BEMTools::extrabits(unsigned encoding, unsigned width) {
    assert(width >= MathTools::bitLength(encoding));
    assert(width > 0);
    return width - MathTools::bitLength(encoding);
}