diff options
Diffstat (limited to 'vendor/gmp-6.3.0/mpn/generic/toom54_mul.c')
-rw-r--r-- | vendor/gmp-6.3.0/mpn/generic/toom54_mul.c | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/vendor/gmp-6.3.0/mpn/generic/toom54_mul.c b/vendor/gmp-6.3.0/mpn/generic/toom54_mul.c new file mode 100644 index 0000000..343b02e --- /dev/null +++ b/vendor/gmp-6.3.0/mpn/generic/toom54_mul.c @@ -0,0 +1,142 @@ +/* Implementation of the algorithm for Toom-Cook 4.5-way. + + Contributed to the GNU project by Marco Bodrato. + + THE FUNCTION IN THIS FILE IS INTERNAL WITH A MUTABLE INTERFACE. IT IS ONLY + SAFE TO REACH IT THROUGH DOCUMENTED INTERFACES. IN FACT, IT IS ALMOST + GUARANTEED THAT IT WILL CHANGE OR DISAPPEAR IN A FUTURE GNU MP RELEASE. + +Copyright 2009, 2012 Free Software Foundation, Inc. + +This file is part of the GNU MP Library. + +The GNU MP Library is free software; you can redistribute it and/or modify +it under the terms of either: + + * the GNU Lesser General Public License as published by the Free + Software Foundation; either version 3 of the License, or (at your + option) any later version. + +or + + * the GNU General Public License as published by the Free Software + Foundation; either version 2 of the License, or (at your option) any + later version. + +or both in parallel, as here. + +The GNU MP Library is distributed in the hope that it will be useful, but +WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY +or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License +for more details. + +You should have received copies of the GNU General Public License and the +GNU Lesser General Public License along with the GNU MP Library. If not, +see https://www.gnu.org/licenses/. */ + +#include "gmp-impl.h" + + +/* Toom-4.5, the splitting 5x4 unbalanced version. + Evaluate in: infinity, +4, -4, +2, -2, +1, -1, 0. + + <--s-><--n--><--n--><--n--><--n--> + ____ ______ ______ ______ ______ + |_a4_|__a3__|__a2__|__a1__|__a0__| + |b3_|__b2__|__b1__|__b0__| + <-t-><--n--><--n--><--n--> + +*/ +#define TOOM_54_MUL_N_REC(p, a, b, n, ws) \ + do { mpn_mul_n (p, a, b, n); \ + } while (0) + +#define TOOM_54_MUL_REC(p, a, na, b, nb, ws) \ + do { mpn_mul (p, a, na, b, nb); \ + } while (0) + +void +mpn_toom54_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 sign; + + /***************************** decomposition *******************************/ +#define a4 (ap + 4 * n) +#define b3 (bp + 3 * n) + + ASSERT (an >= bn); + n = 1 + (4 * an >= 5 * bn ? (an - 1) / (size_t) 5 : (bn - 1) / (size_t) 4); + + s = an - 4 * n; + t = bn - 3 * n; + + ASSERT (0 < s && s <= n); + ASSERT (0 < t && t <= n); + /* Required by mpn_toom_interpolate_8pts. */ + ASSERT ( s + t >= n ); + ASSERT ( s + t > 4); + ASSERT ( n > 2); + +#define r8 pp /* 2n */ +#define r7 scratch /* 3n+1 */ +#define r5 (pp + 3*n) /* 3n+1 */ +#define v0 (pp + 3*n) /* n+1 */ +#define v1 (pp + 4*n+1) /* n+1 */ +#define v2 (pp + 5*n+2) /* n+1 */ +#define v3 (pp + 6*n+3) /* n+1 */ +#define r3 (scratch + 3 * n + 1) /* 3n+1 */ +#define r1 (pp + 7*n) /* s+t <= 2*n */ +#define ws (scratch + 6 * n + 2) /* ??? */ + + /* Alloc also 3n+1 limbs for ws... mpn_toom_interpolate_8pts may + need all of them, when DO_mpn_sublsh_n usea a scratch */ + /********************** evaluation and recursive calls *********************/ + /* $\pm4$ */ + sign = mpn_toom_eval_pm2exp (v2, v0, 4, ap, n, s, 2, pp) + ^ mpn_toom_eval_pm2exp (v3, v1, 3, bp, n, t, 2, pp); + TOOM_54_MUL_N_REC(pp, v0, v1, n + 1, ws); /* A(-4)*B(-4) */ + TOOM_54_MUL_N_REC(r3, v2, v3, n + 1, ws); /* A(+4)*B(+4) */ + mpn_toom_couple_handling (r3, 2*n+1, pp, sign, n, 2, 4); + + /* $\pm1$ */ + sign = mpn_toom_eval_pm1 (v2, v0, 4, ap, n, s, pp) + ^ mpn_toom_eval_dgr3_pm1 (v3, v1, bp, n, t, pp); + TOOM_54_MUL_N_REC(pp, v0, v1, n + 1, ws); /* A(-1)*B(-1) */ + TOOM_54_MUL_N_REC(r7, v2, v3, n + 1, ws); /* A(1)*B(1) */ + mpn_toom_couple_handling (r7, 2*n+1, pp, sign, n, 0, 0); + + /* $\pm2$ */ + sign = mpn_toom_eval_pm2 (v2, v0, 4, ap, n, s, pp) + ^ mpn_toom_eval_dgr3_pm2 (v3, v1, bp, n, t, pp); + TOOM_54_MUL_N_REC(pp, v0, v1, n + 1, ws); /* A(-2)*B(-2) */ + TOOM_54_MUL_N_REC(r5, v2, v3, n + 1, ws); /* A(+2)*B(+2) */ + mpn_toom_couple_handling (r5, 2*n+1, pp, sign, n, 1, 2); + + /* A(0)*B(0) */ + TOOM_54_MUL_N_REC(pp, ap, bp, n, ws); + + /* Infinity */ + if (s > t) { + TOOM_54_MUL_REC(r1, a4, s, b3, t, ws); + } else { + TOOM_54_MUL_REC(r1, b3, t, a4, s, ws); + }; + + mpn_toom_interpolate_8pts (pp, n, r3, r7, s + t, ws); + +#undef a4 +#undef b3 +#undef r1 +#undef r3 +#undef r5 +#undef v0 +#undef v1 +#undef v2 +#undef v3 +#undef r7 +#undef r8 +#undef ws +} |