title: CRC checksum using long (64 bit)
body: <p>I have checked different implementations of CRC64. For example, <a href="http://code.google.com/p/turningpolyhedron/source/browse/trunk/turningpolyhedron/SolverTest2/crc64.cpp?spec=svn202&amp;r=202" rel="noreferrer">this</a>, <a href="http://www.eclemma.org/jacoco/trunk/coverage/org.jacoco.core/org.jacoco.core.internal.data/CRC64.java.html" rel="noreferrer">this</a> and <a href="http://code.activestate.com/recipes/259177-crc64-calculate-the-cyclic-redundancy-check/" rel="noreferrer">this</a>. The problem with all these is that they work with bytes. However, on a 64 bit system, I would like to work with <code>long</code> (8 bytes). In this way, I will need to iterate less. For example, for data of 128 bytes, using a <code>byte</code>, I need to iterate 128 times, while with <code>long</code>, I would need to iterate only 16 times. </p>
  
  <p>Is there any CRC64 implementation that use <code>long</code> or even a word size greater than a byte? Can these schemes be modified to do so?</p>