| /* |
| * Copyright (c) 2008-2012 Stefan Krah. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| */ |
| |
| |
| #include "mpdecimal.h" |
| #include <stdio.h> |
| #include "bits.h" |
| #include "constants.h" |
| #include "fnt.h" |
| #include "fourstep.h" |
| #include "numbertheory.h" |
| #include "sixstep.h" |
| #include "umodarith.h" |
| #include "convolute.h" |
| |
| |
| /* Bignum: Fast convolution using the Number Theoretic Transform. Used for |
| the multiplication of very large coefficients. */ |
| |
| |
| /* Convolute the data in c1 and c2. Result is in c1. */ |
| int |
| fnt_convolute(mpd_uint_t *c1, mpd_uint_t *c2, mpd_size_t n, int modnum) |
| { |
| int (*fnt)(mpd_uint_t *, mpd_size_t, int); |
| int (*inv_fnt)(mpd_uint_t *, mpd_size_t, int); |
| #ifdef PPRO |
| double dmod; |
| uint32_t dinvmod[3]; |
| #endif |
| mpd_uint_t n_inv, umod; |
| mpd_size_t i; |
| |
| |
| SETMODULUS(modnum); |
| n_inv = POWMOD(n, (umod-2)); |
| |
| if (ispower2(n)) { |
| if (n > SIX_STEP_THRESHOLD) { |
| fnt = six_step_fnt; |
| inv_fnt = inv_six_step_fnt; |
| } |
| else { |
| fnt = std_fnt; |
| inv_fnt = std_inv_fnt; |
| } |
| } |
| else { |
| fnt = four_step_fnt; |
| inv_fnt = inv_four_step_fnt; |
| } |
| |
| if (!fnt(c1, n, modnum)) { |
| return 0; |
| } |
| if (!fnt(c2, n, modnum)) { |
| return 0; |
| } |
| for (i = 0; i < n-1; i += 2) { |
| mpd_uint_t x0 = c1[i]; |
| mpd_uint_t y0 = c2[i]; |
| mpd_uint_t x1 = c1[i+1]; |
| mpd_uint_t y1 = c2[i+1]; |
| MULMOD2(&x0, y0, &x1, y1); |
| c1[i] = x0; |
| c1[i+1] = x1; |
| } |
| |
| if (!inv_fnt(c1, n, modnum)) { |
| return 0; |
| } |
| for (i = 0; i < n-3; i += 4) { |
| mpd_uint_t x0 = c1[i]; |
| mpd_uint_t x1 = c1[i+1]; |
| mpd_uint_t x2 = c1[i+2]; |
| mpd_uint_t x3 = c1[i+3]; |
| MULMOD2C(&x0, &x1, n_inv); |
| MULMOD2C(&x2, &x3, n_inv); |
| c1[i] = x0; |
| c1[i+1] = x1; |
| c1[i+2] = x2; |
| c1[i+3] = x3; |
| } |
| |
| return 1; |
| } |
| |
| /* Autoconvolute the data in c1. Result is in c1. */ |
| int |
| fnt_autoconvolute(mpd_uint_t *c1, mpd_size_t n, int modnum) |
| { |
| int (*fnt)(mpd_uint_t *, mpd_size_t, int); |
| int (*inv_fnt)(mpd_uint_t *, mpd_size_t, int); |
| #ifdef PPRO |
| double dmod; |
| uint32_t dinvmod[3]; |
| #endif |
| mpd_uint_t n_inv, umod; |
| mpd_size_t i; |
| |
| |
| SETMODULUS(modnum); |
| n_inv = POWMOD(n, (umod-2)); |
| |
| if (ispower2(n)) { |
| if (n > SIX_STEP_THRESHOLD) { |
| fnt = six_step_fnt; |
| inv_fnt = inv_six_step_fnt; |
| } |
| else { |
| fnt = std_fnt; |
| inv_fnt = std_inv_fnt; |
| } |
| } |
| else { |
| fnt = four_step_fnt; |
| inv_fnt = inv_four_step_fnt; |
| } |
| |
| if (!fnt(c1, n, modnum)) { |
| return 0; |
| } |
| for (i = 0; i < n-1; i += 2) { |
| mpd_uint_t x0 = c1[i]; |
| mpd_uint_t x1 = c1[i+1]; |
| MULMOD2(&x0, x0, &x1, x1); |
| c1[i] = x0; |
| c1[i+1] = x1; |
| } |
| |
| if (!inv_fnt(c1, n, modnum)) { |
| return 0; |
| } |
| for (i = 0; i < n-3; i += 4) { |
| mpd_uint_t x0 = c1[i]; |
| mpd_uint_t x1 = c1[i+1]; |
| mpd_uint_t x2 = c1[i+2]; |
| mpd_uint_t x3 = c1[i+3]; |
| MULMOD2C(&x0, &x1, n_inv); |
| MULMOD2C(&x2, &x3, n_inv); |
| c1[i] = x0; |
| c1[i+1] = x1; |
| c1[i+2] = x2; |
| c1[i+3] = x3; |
| } |
| |
| return 1; |
| } |
| |
| |