libs/libtommath/bn_mp_dr_setup.c

   1 #include <tommath.h>
   2 #ifdef BN_MP_DR_SETUP_C
   3 /* LibTomMath, multiple-precision integer library -- Tom St Denis
   4  *
   5  * LibTomMath is a library that provides multiple-precision
   6  * integer arithmetic as well as number theoretic functionality.
   7  *
   8  * The library was designed directly after the MPI library by
   9  * Michael Fromberger but has been written from scratch with
  10  * additional optimizations in place.
  11  *
  12  * The library is free for all purposes without any express
  13  * guarantee it works.
  14  *
  15  * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
  16  */
  17
  18 /* determines the setup value */
  19 void mp_dr_setup(mp_int *a, mp_digit *d)
  20 {
  21    /* the casts are required if DIGIT_BIT is one less than
  22     * the number of bits in a mp_digit [e.g. DIGIT_BIT==31]
  23     */
  24    *d = (mp_digit)((((mp_word)1) << ((mp_word)DIGIT_BIT)) -
  25         ((mp_word)a->dp[0]));
  26 }
  27
  28 #endif
  29
  30 /* $Source: /cvs/libtom/libtommath/bn_mp_dr_setup.c,v $ */
  31 /* $Revision: 1.4 $ */
  32 /* $Date: 2006/12/28 01:25:13 $ */