Exemple #1
0
/* Check schoolboy division routine. */
void
check_sb_div_q (void)
{
   mp_limb_t np[2*MAX_LIMBS];
   mp_limb_t np2[2*MAX_LIMBS];
   mp_limb_t rp[2*MAX_LIMBS+1];
   mp_limb_t dp[MAX_LIMBS];
   mp_limb_t qp[2*MAX_LIMBS];
   mp_limb_t dip, cy;

   mp_size_t nn, rn, dn, qn;

   gmp_randstate_t rands;

   int i, j, s;
   gmp_randinit_default(rands);
  
   for (i = 0; i < ITERS; i++)
   {
      dn = (random() % (MAX_LIMBS - 2)) + 3;
      nn = (random() % MAX_LIMBS) + dn;
      
      mpn_rrandom (np, rands, nn);
      mpn_rrandom (dp, rands, dn);
      dp[dn-1] |= GMP_LIMB_HIGHBIT;

      MPN_COPY(np2, np, nn);
      
      mpir_invert_pi2(dip, dp[dn - 1], dp[dn - 2]);
      
      qn = nn - dn + 1;
         
      qp[qn - 1] = mpn_sb_div_q(qp, np, nn, dp, dn, dip);

      MPN_NORMALIZE(qp, qn);

      if (qn)
      {
         if (qn >= dn) mpn_mul(rp, qp, qn, dp, dn);
         else mpn_mul(rp, dp, dn, qp, qn);
      
         rn = dn + qn;
         MPN_NORMALIZE(rp, rn);
         
         if (rn > nn)
         {
            printf("failed: q*d has too many limbs\n");
            abort();
         }
         
         if (mpn_cmp(rp, np2, nn) > 0)
         {
            printf("failed: remainder negative\n");
            abort();
         }
         
         mpn_sub(rp, np2, nn, rp, rn);
         rn = nn;
         MPN_NORMALIZE(rp, rn);
      } else
      {
         rn = nn;
         MPN_COPY(rp, np, nn);
      }
      
      s = (rn < dn) ? -1 : (rn > dn) ? 1 : mpn_cmp(rp, dp, dn);
      if (s >= 0)
      {
         printf ("failed:\n");
         printf ("nn = %lu, dn = %lu, qn = %lu, rn = %lu\n\n", nn, dn, qn, rn);
         gmp_printf (" np: %Nx\n\n", np2, nn);
         gmp_printf (" dp: %Nx\n\n", dp, dn);
         gmp_printf (" qp: %Nx\n\n", qp, qn);
         gmp_printf (" rp: %Nx\n\n", rp, rn);
         abort ();
      }
   }

   gmp_randclear(rands);
}
Exemple #2
0
/* Check divide and conquer division routine. */
void
check_dc_divappr_q_n (void)
{
   mp_limb_t tp[DC_DIVAPPR_Q_N_ITCH(MAX_LIMBS)];
   mp_limb_t np[2*MAX_LIMBS];
   mp_limb_t np2[2*MAX_LIMBS];
   mp_limb_t rp[2*MAX_LIMBS];
   mp_limb_t dp[MAX_LIMBS];
   mp_limb_t qp[MAX_LIMBS];
   mp_limb_t dip, d1ip;

   mp_size_t nn, rn, dn, qn;

   gmp_randstate_t rands;

   int i, j, s;
   gmp_randinit_default(rands);
  
   for (i = 0; i < ITERS; i++)
   {
      dn = (random() % (MAX_LIMBS - 6)) + 6;
      nn = 2*dn;
         
      mpn_rrandom (np, rands, nn);
      mpn_rrandom (dp, rands, dn);
      dp[dn-1] |= GMP_LIMB_HIGHBIT;

      MPN_COPY(np2, np, nn);
      
      mpir_invert_pi2(dip, d1ip, dp[dn - 1], dp[dn - 2]);
      
      qn = nn - dn + 1;
         
      qp[qn - 1] = mpn_dc_divappr_q_n(qp, np, dp, dn, dip, d1ip, tp);
      
      MPN_NORMALIZE(qp, qn);

      if (qn)
      {
         if (qn >= dn) mpn_mul(rp, qp, qn, dp, dn);
         else mpn_mul(rp, dp, dn, qp, qn);

         rn = dn + qn;
         MPN_NORMALIZE(rp, rn);

         s = (rn < nn) ? -1 : (rn > nn) ? 1 : mpn_cmp(rp, np2, nn);
         if (s <= 0) 
         {
            mpn_sub(rp, np2, nn, rp, rn);
            rn = nn;
            MPN_NORMALIZE(rp, rn);
         } else 
         {
            mpn_sub(rp, rp, rn, np2, nn);
            MPN_NORMALIZE(rp, rn);
         }
      } else
      {
         rn = nn;
         MPN_COPY(rp, np, nn);
      }
      
      s = (rn < dn) ? -1 : (rn > dn) ? 1 : mpn_cmp(rp, dp, dn);
      if (s >= 0)
      {
         printf ("failed:\n");
         printf ("nn = %lu, dn = %lu, qn = %lu, rn = %lu\n\n", nn, dn, qn, rn);
         gmp_printf (" np: %Nx\n\n", np2, nn);
         gmp_printf (" dp: %Nx\n\n", dp, dn);
         gmp_printf (" qp: %Nx\n\n", qp, qn);
         gmp_printf (" rp: %Nx\n\n", rp, rn);
         abort ();
      }
   }

   gmp_randclear(rands);
}