text: #include <tommath.h>
  #ifdef BN_MP_CNT_LSB_C
  /* LibTomMath, multiple-precision integer library -- Tom St Denis
   *
   * LibTomMath is a library that provides multiple-precision
   * integer arithmetic as well as number theoretic functionality.
   *
   * The library was designed directly after the MPI library by
   * Michael Fromberger but has been written from scratch with
   * additional optimizations in place.
   *
   * The library is free for all purposes without any express
   * guarantee it works.
   *
   * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
   */
  
  static const int lnz[16] = { 
     4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0
  };
  
  /* Counts the number of lsbs which are zero before the first zero bit */
  int mp_cnt_lsb(mp_int *a)
  {
     int x;
     mp_digit q, qq;
  
     /* easy out */
     if (mp_iszero(a) == 1) {
        return 0;
     }
  
     /* scan lower digits until non-zero */
     for (x = 0; x < a->used && a->dp[x] == 0; x++);
     q = a->dp[x];
     x *= DIGIT_BIT;
  
     /* now scan this digit until a 1 is found */
     if ((q & 1) == 0) {
        do {
           qq  = q & 15;
           x  += lnz[qq];
           q >>= 4;
        } while (qq == 0);
     }
     return x;
  }
  
  #endif
  
  /* $Source: /cvs/libtom/libtommath/bn_mp_cnt_lsb.c,v $ */
  /* $Revision: 1.4 $ */
  /* $Date: 2006/12/28 01:25:13 $ */
  