kc3-lang/libtommath/mp_signed_rsh.c

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• Hash : 1cc289d2
  Author :
  Date : 2019-11-09T20:23:03
  

  better use of mp_isneg() and mp_iszero()

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• mp_signed_rsh.c

• #include "tommath_private.h"
  #ifdef MP_SIGNED_RSH_C
  /* LibTomMath, multiple-precision integer library -- Tom St Denis */
  /* SPDX-License-Identifier: Unlicense */
  
  /* shift right by a certain bit count with sign extension */
  mp_err mp_signed_rsh(const mp_int *a, int b, mp_int *c)
  {
     mp_err err;
     if (!mp_isneg(a)) {
        return mp_div_2d(a, b, c, NULL);
     }
  
     if ((err = mp_add_d(a, 1uL, c)) != MP_OKAY) {
        return err;
     }
  
     err = mp_div_2d(c, b, c, NULL);
     return (err == MP_OKAY) ? mp_sub_d(c, 1uL, c) : err;
  }
  #endif
  

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