示例#1
0
void
mpn_toom4_sqr (mp_ptr pp,
               mp_srcptr ap, mp_size_t an,
               mp_ptr scratch)
{
    mp_size_t n, s;
    mp_limb_t cy;

#define a0  ap
#define a1  (ap + n)
#define a2  (ap + 2*n)
#define a3  (ap + 3*n)

    n = (an + 3) >> 2;

    s = an - 3 * n;

    ASSERT (0 < s && s <= n);

    /* NOTE: The multiplications to v2, vm2, vh and vm1 overwrites the
     * following limb, so these must be computed in order, and we need a
     * one limb gap to tp. */
#define v0    pp				/* 2n */
#define v1    (pp + 2 * n)			/* 2n+1 */
#define vinf  (pp + 6 * n)			/* s+t */
#define v2    scratch				/* 2n+1 */
#define vm2   (scratch + 2 * n + 1)		/* 2n+1 */
#define vh    (scratch + 4 * n + 2)		/* 2n+1 */
#define vm1   (scratch + 6 * n + 3)		/* 2n+1 */
#define tp (scratch + 8*n + 5)

    /* No overlap with v1 */
#define apx   pp				/* n+1 */
#define amx   (pp + 4*n + 2)			/* n+1 */

    /* Total scratch need: 8*n + 5 + scratch for recursive calls. This
       gives roughly 32 n/3 + log term. */

    /* Compute apx = a0 + 2 a1 + 4 a2 + 8 a3 and amx = a0 - 2 a1 + 4 a2 - 8 a3.  */
    mpn_toom_eval_dgr3_pm2 (apx, amx, ap, n, s, tp);

    TOOM4_SQR_REC (v2, apx, n + 1, tp);	/* v2,  2n+1 limbs */
    TOOM4_SQR_REC (vm2, amx, n + 1, tp);	/* vm2,  2n+1 limbs */

    /* Compute apx = 8 a0 + 4 a1 + 2 a2 + a3 = (((2*a0 + a1) * 2 + a2) * 2 + a3 */
#if HAVE_NATIVE_mpn_addlsh1_n
    cy = mpn_addlsh1_n (apx, a1, a0, n);
    cy = 2*cy + mpn_addlsh1_n (apx, a2, apx, n);
    if (s < n)
    {
        mp_limb_t cy2;
        cy2 = mpn_addlsh1_n (apx, a3, apx, s);
        apx[n] = 2*cy + mpn_lshift (apx + s, apx + s, n - s, 1);
        MPN_INCR_U (apx + s, n+1-s, cy2);
    }
    else
        apx[n] = 2*cy + mpn_addlsh1_n (apx, a3, apx, n);
#else
    cy = mpn_lshift (apx, a0, n, 1);
    cy += mpn_add_n (apx, apx, a1, n);
    cy = 2*cy + mpn_lshift (apx, apx, n, 1);
    cy += mpn_add_n (apx, apx, a2, n);
    cy = 2*cy + mpn_lshift (apx, apx, n, 1);
    apx[n] = cy + mpn_add (apx, apx, n, a3, s);
#endif

    ASSERT (apx[n] < 15);

    TOOM4_SQR_REC (vh, apx, n + 1, tp);	/* vh,  2n+1 limbs */

    /* Compute apx = a0 + a1 + a2 + a3 and amx = a0 - a1 + a2 - a3.  */
    mpn_toom_eval_dgr3_pm1 (apx, amx, ap, n, s, tp);

    TOOM4_SQR_REC (v1, apx, n + 1, tp);	/* v1,  2n+1 limbs */
    TOOM4_SQR_REC (vm1, amx, n + 1, tp);	/* vm1,  2n+1 limbs */

    TOOM4_SQR_REC (v0, a0, n, tp);
    TOOM4_SQR_REC (vinf, a3, s, tp);	/* vinf, 2s limbs */

    mpn_toom_interpolate_7pts (pp, n, 0, vm2, vm1, v2, vh, 2*s, tp);
}
示例#2
0
void
mpn_toom6h_mul   (mp_ptr pp,
		  mp_srcptr ap, mp_size_t an,
		  mp_srcptr bp, mp_size_t bn, mp_ptr scratch)
{
  mp_size_t n, s, t;
  int p, q, half;
  int sign;

  /***************************** decomposition *******************************/

  ASSERT (an >= bn);
  /* Can not handle too much unbalancement */
  ASSERT (bn >= 42);
  /* Can not handle too much unbalancement */
  ASSERT ((an*3 <  bn * 8) || (bn >= 46 && an * 6 <  bn * 17));

  /* Limit num/den is a rational number between
     (12/11)^(log(4)/log(2*4-1)) and (12/11)^(log(6)/log(2*6-1))             */
#define LIMIT_numerator (18)
#define LIMIT_denominat (17)

  if (LIKELY (an * LIMIT_denominat < LIMIT_numerator * bn)) /* is 6*... < 6*... */
    {
      n = 1 + (an - 1) / (size_t) 6;
      p = q = 5;
      half = 0;

      s = an - 5 * n;
      t = bn - 5 * n;
    }
  else {
    if (an * 5 * LIMIT_numerator < LIMIT_denominat * 7 * bn)
      { p = 7; q = 6; }
    else if (an * 5 * LIMIT_denominat < LIMIT_numerator * 7 * bn)
      { p = 7; q = 5; }
    else if (an * LIMIT_numerator < LIMIT_denominat * 2 * bn)  /* is 4*... < 8*... */
      { p = 8; q = 5; }
    else if (an * LIMIT_denominat < LIMIT_numerator * 2 * bn)  /* is 4*... < 8*... */
      { p = 8; q = 4; }
    else
      { p = 9; q = 4; }

    half = (p ^ q) & 1;
    n = 1 + (q * an >= p * bn ? (an - 1) / (size_t) p : (bn - 1) / (size_t) q);
    p--; q--;

    s = an - p * n;
    t = bn - q * n;

    /* With LIMIT = 16/15, the following recover is needed only if bn<=73*/
    if (half) { /* Recover from badly chosen splitting */
      if (UNLIKELY (s<1)) {p--; s+=n; half=0;}
      else if (UNLIKELY (t<1)) {q--; t+=n; half=0;}
    }
  }
#undef LIMIT_numerator
#undef LIMIT_denominat

  ASSERT (0 < s && s <= n);
  ASSERT (0 < t && t <= n);
  ASSERT (half || s + t > 3);
  ASSERT (n > 2);

#define   r4    (pp + 3 * n)			/* 3n+1 */
#define   r2    (pp + 7 * n)			/* 3n+1 */
#define   r0    (pp +11 * n)			/* s+t <= 2*n */
#define   r5    (scratch)			/* 3n+1 */
#define   r3    (scratch + 3 * n + 1)		/* 3n+1 */
#define   r1    (scratch + 6 * n + 2)		/* 3n+1 */
#define   v0    (pp + 7 * n)			/* n+1 */
#define   v1    (pp + 8 * n+1)			/* n+1 */
#define   v2    (pp + 9 * n+2)			/* n+1 */
#define   v3    (scratch + 9 * n + 3)		/* n+1 */
#define   wsi   (scratch + 9 * n + 3)		/* 3n+1 */
#define   wse   (scratch +10 * n + 4)		/* 2n+1 */

  /* Alloc also 3n+1 limbs for wsi... toom_interpolate_12pts may
     need all of them  */
/*   if (scratch == NULL) */
/*     scratch = TMP_SALLOC_LIMBS(mpn_toom6_sqr_itch(n * 6)); */
  ASSERT (12 * n + 6 <= mpn_toom6h_mul_itch(an,bn));
  ASSERT (12 * n + 6 <= mpn_toom6_sqr_itch(n * 6));

  /********************** evaluation and recursive calls *********************/
  /* $\pm1/2$ */
  sign = mpn_toom_eval_pm2rexp (v2, v0, p, ap, n, s, 1, pp) ^
	 mpn_toom_eval_pm2rexp (v3, v1, q, bp, n, t, 1, pp);
  /* A(-1/2)*B(-1/2)*2^. */ /* A(+1/2)*B(+1/2)*2^. */
  TOOM6H_MUL_N_REC(pp, v0, v1, 2, r5, v2, v3, n + 1, wse);
  mpn_toom_couple_handling (r5, 2 * n + 1, pp, sign, n, 1+half , half);

  /* $\pm1$ */
  sign = mpn_toom_eval_pm1 (v2, v0, p, ap, n, s,    pp);
  if (UNLIKELY (q == 3))
    sign ^= mpn_toom_eval_dgr3_pm1 (v3, v1, bp, n, t,    pp);
  else
    sign ^= mpn_toom_eval_pm1 (v3, v1, q, bp, n, t,    pp);
  /* A(-1)*B(-1) */ /* A(1)*B(1) */
  TOOM6H_MUL_N_REC(pp, v0, v1, 2, r3, v2, v3, n + 1, wse);
  mpn_toom_couple_handling (r3, 2 * n + 1, pp, sign, n, 0, 0);

  /* $\pm4$ */
  sign = mpn_toom_eval_pm2exp (v2, v0, p, ap, n, s, 2, pp) ^
	 mpn_toom_eval_pm2exp (v3, v1, q, bp, n, t, 2, pp);
  /* A(-4)*B(-4) */
  TOOM6H_MUL_N_REC(pp, v0, v1, 2, r1, v2, v3, n + 1, wse); /* A(+4)*B(+4) */
  mpn_toom_couple_handling (r1, 2 * n + 1, pp, sign, n, 2, 4);

  /* $\pm1/4$ */
  sign = mpn_toom_eval_pm2rexp (v2, v0, p, ap, n, s, 2, pp) ^
	 mpn_toom_eval_pm2rexp (v3, v1, q, bp, n, t, 2, pp);
  /* A(-1/4)*B(-1/4)*4^. */ /* A(+1/4)*B(+1/4)*4^. */
  TOOM6H_MUL_N_REC(pp, v0, v1, 2, r4, v2, v3, n + 1, wse);
  mpn_toom_couple_handling (r4, 2 * n + 1, pp, sign, n, 2*(1+half), 2*(half));

  /* $\pm2$ */
  sign = mpn_toom_eval_pm2 (v2, v0, p, ap, n, s, pp) ^
	 mpn_toom_eval_pm2 (v3, v1, q, bp, n, t, pp);
  /* A(-2)*B(-2) */ /* A(+2)*B(+2) */
  TOOM6H_MUL_N_REC(pp, v0, v1, 2, r2, v2, v3, n + 1, wse);
  mpn_toom_couple_handling (r2, 2 * n + 1, pp, sign, n, 1, 2);

#undef v0
#undef v1
#undef v2
#undef v3
#undef wse

  /* A(0)*B(0) */
  TOOM6H_MUL_N_REC(pp, ap, bp, 0, pp, ap, bp, n, wsi);

  /* Infinity */
  if (UNLIKELY (half != 0)) {
    if (s > t) {
      TOOM6H_MUL_REC(r0, ap + p * n, s, bp + q * n, t, wsi);
    } else {
      TOOM6H_MUL_REC(r0, bp + q * n, t, ap + p * n, s, wsi);
    };
  };

  mpn_toom_interpolate_12pts (pp, r1, r3, r5, n, s+t, half, wsi);

#undef r0
#undef r1
#undef r2
#undef r3
#undef r4
#undef r5
#undef wsi
}
示例#3
0
void
mpn_toom44_mul (mp_ptr pp,
		mp_srcptr ap, mp_size_t an,
		mp_srcptr bp, mp_size_t bn,
		mp_ptr scratch)
{
  mp_size_t n, s, t;
  mp_limb_t cy;
  enum toom7_flags flags;

#define a0  ap
#define a1  (ap + n)
#define a2  (ap + 2*n)
#define a3  (ap + 3*n)
#define b0  bp
#define b1  (bp + n)
#define b2  (bp + 2*n)
#define b3  (bp + 3*n)

  ASSERT (an >= bn);

  n = (an + 3) >> 2;

  s = an - 3 * n;
  t = bn - 3 * n;

  ASSERT (0 < s && s <= n);
  ASSERT (0 < t && t <= n);
  ASSERT (s >= t);

  /* NOTE: The multiplications to v2, vm2, vh and vm1 overwrites the
   * following limb, so these must be computed in order, and we need a
   * one limb gap to tp. */
#define v0    pp				/* 2n */
#define v1    (pp + 2 * n)			/* 2n+1 */
#define vinf  (pp + 6 * n)			/* s+t */
#define v2    scratch				/* 2n+1 */
#define vm2   (scratch + 2 * n + 1)		/* 2n+1 */
#define vh    (scratch + 4 * n + 2)		/* 2n+1 */
#define vm1   (scratch + 6 * n + 3)		/* 2n+1 */
#define tp (scratch + 8*n + 5)

  /* apx and bpx must not overlap with v1 */
#define apx   pp				/* n+1 */
#define amx   (pp + n + 1)			/* n+1 */
#define bmx   (pp + 2*n + 2)			/* n+1 */
#define bpx   (pp + 4*n + 2)			/* n+1 */

  /* Total scratch need: 8*n + 5 + scratch for recursive calls. This
     gives roughly 32 n/3 + log term. */

  /* Compute apx = a0 + 2 a1 + 4 a2 + 8 a3 and amx = a0 - 2 a1 + 4 a2 - 8 a3.  */
  flags = (enum toom7_flags) (toom7_w1_neg & mpn_toom_eval_dgr3_pm2 (apx, amx, ap, n, s, tp));

  /* Compute bpx = b0 + 2 b1 + 4 b2 + 8 b3 and bmx = b0 - 2 b1 + 4 b2 - 8 b3.  */
  flags = (enum toom7_flags) (flags ^ toom7_w1_neg & mpn_toom_eval_dgr3_pm2 (bpx, bmx, bp, n, t, tp));

  TOOM44_MUL_N_REC (v2, apx, bpx, n + 1, tp);	/* v2,  2n+1 limbs */
  TOOM44_MUL_N_REC (vm2, amx, bmx, n + 1, tp);	/* vm2,  2n+1 limbs */

  /* Compute apx = 8 a0 + 4 a1 + 2 a2 + a3 = (((2*a0 + a1) * 2 + a2) * 2 + a3 */
#if HAVE_NATIVE_mpn_addlsh1_n
  cy = mpn_addlsh1_n (apx, a1, a0, n);
  cy = 2*cy + mpn_addlsh1_n (apx, a2, apx, n);
  if (s < n)
    {
      mp_limb_t cy2;
      cy2 = mpn_addlsh1_n (apx, a3, apx, s);
      apx[n] = 2*cy + mpn_lshift (apx + s, apx + s, n - s, 1);
      MPN_INCR_U (apx + s, n+1-s, cy2);
    }
  else
    apx[n] = 2*cy + mpn_addlsh1_n (apx, a3, apx, n);
#else
  cy = mpn_lshift (apx, a0, n, 1);
  cy += mpn_add_n (apx, apx, a1, n);
  cy = 2*cy + mpn_lshift (apx, apx, n, 1);
  cy += mpn_add_n (apx, apx, a2, n);
  cy = 2*cy + mpn_lshift (apx, apx, n, 1);
  apx[n] = cy + mpn_add (apx, apx, n, a3, s);
#endif

  /* Compute bpx = 8 b0 + 4 b1 + 2 b2 + b3 = (((2*b0 + b1) * 2 + b2) * 2 + b3 */
#if HAVE_NATIVE_mpn_addlsh1_n
  cy = mpn_addlsh1_n (bpx, b1, b0, n);
  cy = 2*cy + mpn_addlsh1_n (bpx, b2, bpx, n);
  if (t < n)
    {
      mp_limb_t cy2;
      cy2 = mpn_addlsh1_n (bpx, b3, bpx, t);
      bpx[n] = 2*cy + mpn_lshift (bpx + t, bpx + t, n - t, 1);
      MPN_INCR_U (bpx + t, n+1-t, cy2);
    }
  else
    bpx[n] = 2*cy + mpn_addlsh1_n (bpx, b3, bpx, n);
#else
  cy = mpn_lshift (bpx, b0, n, 1);
  cy += mpn_add_n (bpx, bpx, b1, n);
  cy = 2*cy + mpn_lshift (bpx, bpx, n, 1);
  cy += mpn_add_n (bpx, bpx, b2, n);
  cy = 2*cy + mpn_lshift (bpx, bpx, n, 1);
  bpx[n] = cy + mpn_add (bpx, bpx, n, b3, t);
#endif

  ASSERT (apx[n] < 15);
  ASSERT (bpx[n] < 15);

  TOOM44_MUL_N_REC (vh, apx, bpx, n + 1, tp);	/* vh,  2n+1 limbs */

  /* Compute apx = a0 + a1 + a2 + a3 and amx = a0 - a1 + a2 - a3.  */
  flags = (enum toom7_flags) (flags | toom7_w3_neg & mpn_toom_eval_dgr3_pm1 (apx, amx, ap, n, s, tp));

  /* Compute bpx = b0 + b1 + b2 + b3 bnd bmx = b0 - b1 + b2 - b3.  */
  flags = (enum toom7_flags) (flags ^ toom7_w3_neg & mpn_toom_eval_dgr3_pm1 (bpx, bmx, bp, n, t, tp));

  TOOM44_MUL_N_REC (vm1, amx, bmx, n + 1, tp);	/* vm1,  2n+1 limbs */
  /* Clobbers amx, bmx. */
  TOOM44_MUL_N_REC (v1, apx, bpx, n + 1, tp);	/* v1,  2n+1 limbs */

  TOOM44_MUL_N_REC (v0, a0, b0, n, tp);
  if (s > t)
    mpn_mul (vinf, a3, s, b3, t);
  else
    TOOM44_MUL_N_REC (vinf, a3, b3, s, tp);	/* vinf, s+t limbs */

  mpn_toom_interpolate_7pts (pp, n, flags, vm2, vm1, v2, vh, s + t, tp);
}