From 11da511c784eca003deb90c23570f0873954e0de Mon Sep 17 00:00:00 2001 From: Duncan Wilkie Date: Sat, 18 Nov 2023 06:11:09 -0600 Subject: Initial commit. --- gmp-6.3.0/mpn/generic/toom63_mul.c | 231 +++++++++++++++++++++++++++++++++++++ 1 file changed, 231 insertions(+) create mode 100644 gmp-6.3.0/mpn/generic/toom63_mul.c (limited to 'gmp-6.3.0/mpn/generic/toom63_mul.c') diff --git a/gmp-6.3.0/mpn/generic/toom63_mul.c b/gmp-6.3.0/mpn/generic/toom63_mul.c new file mode 100644 index 0000000..181996d --- /dev/null +++ b/gmp-6.3.0/mpn/generic/toom63_mul.c @@ -0,0 +1,231 @@ +/* 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" + +/* Stores |{ap,n}-{bp,n}| in {rp,n}, returns the sign. */ +static int +abs_sub_n (mp_ptr rp, mp_srcptr ap, mp_srcptr bp, mp_size_t n) +{ + mp_limb_t x, y; + while (--n >= 0) + { + x = ap[n]; + y = bp[n]; + if (x != y) + { + n++; + if (x > y) + { + mpn_sub_n (rp, ap, bp, n); + return 0; + } + else + { + mpn_sub_n (rp, bp, ap, n); + return ~0; + } + } + rp[n] = 0; + } + return 0; +} + +static int +abs_sub_add_n (mp_ptr rm, mp_ptr rp, mp_srcptr rs, mp_size_t n) { + int result; + result = abs_sub_n (rm, rp, rs, n); + ASSERT_NOCARRY(mpn_add_n (rp, rp, rs, n)); + return result; +} + + +/* Toom-4.5, the splitting 6x3 unbalanced version. + Evaluate in: infinity, +4, -4, +2, -2, +1, -1, 0. + + <--s-><--n--><--n--><--n--><--n--><--n--> + ____ ______ ______ ______ ______ ______ + |_a5_|__a4__|__a3__|__a2__|__a1__|__a0__| + |b2_|__b1__|__b0__| + <-t-><--n--><--n--> + +*/ +#define TOOM_63_MUL_N_REC(p, a, b, n, ws) \ + do { mpn_mul_n (p, a, b, n); \ + } while (0) + +#define TOOM_63_MUL_REC(p, a, na, b, nb, ws) \ + do { mpn_mul (p, a, na, b, nb); \ + } while (0) + +void +mpn_toom63_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; + int sign; + + /***************************** decomposition *******************************/ +#define a5 (ap + 5 * n) +#define b0 (bp + 0 * n) +#define b1 (bp + 1 * n) +#define b2 (bp + 2 * n) + + ASSERT (an >= bn); + n = 1 + (an >= 2 * bn ? (an - 1) / (size_t) 6 : (bn - 1) / (size_t) 3); + + s = an - 5 * n; + t = bn - 2 * n; + + ASSERT (0 < s && s <= n); + ASSERT (0 < t && t <= n); + /* WARNING! it assumes s+t>=n */ + ASSERT ( s + t >= n ); + ASSERT ( s + t > 4); + /* WARNING! it assumes n>1 */ + 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 */ +/* if (scratch == NULL) scratch = TMP_SALLOC_LIMBS (9 * n + 3); */ + + /********************** evaluation and recursive calls *********************/ + /* $\pm4$ */ + sign = mpn_toom_eval_pm2exp (v2, v0, 5, ap, n, s, 2, pp); + pp[n] = mpn_lshift (pp, b1, n, 2); /* 4b1 */ + /* FIXME: use addlsh */ + v3[t] = mpn_lshift (v3, b2, t, 4);/* 16b2 */ + if ( n == t ) + v3[n]+= mpn_add_n (v3, v3, b0, n); /* 16b2+b0 */ + else + v3[n] = mpn_add (v3, b0, n, v3, t+1); /* 16b2+b0 */ + sign ^= abs_sub_add_n (v1, v3, pp, n + 1); + TOOM_63_MUL_N_REC(pp, v0, v1, n + 1, ws); /* A(-4)*B(-4) */ + TOOM_63_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, 5, ap, n, s, pp); + /* Compute bs1 and bsm1. Code taken from toom33 */ + cy = mpn_add (ws, b0, n, b2, t); +#if HAVE_NATIVE_mpn_add_n_sub_n + if (cy == 0 && mpn_cmp (ws, b1, n) < 0) + { + cy = mpn_add_n_sub_n (v3, v1, b1, ws, n); + v3[n] = cy >> 1; + v1[n] = 0; + sign = ~sign; + } + else + { + mp_limb_t cy2; + cy2 = mpn_add_n_sub_n (v3, v1, ws, b1, n); + v3[n] = cy + (cy2 >> 1); + v1[n] = cy - (cy2 & 1); + } +#else + v3[n] = cy + mpn_add_n (v3, ws, b1, n); + if (cy == 0 && mpn_cmp (ws, b1, n) < 0) + { + mpn_sub_n (v1, b1, ws, n); + v1[n] = 0; + sign = ~sign; + } + else + { + cy -= mpn_sub_n (v1, ws, b1, n); + v1[n] = cy; + } +#endif + TOOM_63_MUL_N_REC(pp, v0, v1, n + 1, ws); /* A(-1)*B(-1) */ + TOOM_63_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, 5, ap, n, s, pp); + pp[n] = mpn_lshift (pp, b1, n, 1); /* 2b1 */ + /* FIXME: use addlsh or addlsh2 */ + v3[t] = mpn_lshift (v3, b2, t, 2);/* 4b2 */ + if ( n == t ) + v3[n]+= mpn_add_n (v3, v3, b0, n); /* 4b2+b0 */ + else + v3[n] = mpn_add (v3, b0, n, v3, t+1); /* 4b2+b0 */ + sign ^= abs_sub_add_n (v1, v3, pp, n + 1); + TOOM_63_MUL_N_REC(pp, v0, v1, n + 1, ws); /* A(-2)*B(-2) */ + TOOM_63_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_63_MUL_N_REC(pp, ap, bp, n, ws); + + /* Infinity */ + if (s > t) { + TOOM_63_MUL_REC(r1, a5, s, b2, t, ws); + } else { + TOOM_63_MUL_REC(r1, b2, t, a5, s, ws); + }; + + mpn_toom_interpolate_8pts (pp, n, r3, r7, s + t, ws); + +#undef a5 +#undef b0 +#undef b1 +#undef b2 +#undef r1 +#undef r3 +#undef r5 +#undef v0 +#undef v1 +#undef v2 +#undef v3 +#undef r7 +#undef r8 +#undef ws +} -- cgit v1.2.3