1 /* Copyright (c) 2014-2016 Cryptography Research, Inc.
2 * Released under the MIT License. See LICENSE.txt for license information.
5 #define GF_HEADROOM 9999 /* Everything is reduced anyway */
6 #define FIELD_LITERAL(a,b,c,d,e,f,g,h) {{a,b,c,d,e,f,g,h}}
8 #define LIMB_PLACE_VALUE(i) 56
10 void gf_add_RAW (gf out, const gf a, const gf b) {
11 for (unsigned int i=0; i<8; i++) {
12 out->limb[i] = a->limb[i] + b->limb[i];
17 void gf_sub_RAW (gf out, const gf a, const gf b) {
18 uint64_t co1 = ((1ull<<56)-1)*2, co2 = co1-2;
19 for (unsigned int i=0; i<8; i++) {
20 out->limb[i] = a->limb[i] - b->limb[i] + ((i==4) ? co2 : co1);
25 void gf_bias (gf a, int amt) {
30 void gf_weak_reduce (gf a) {
31 uint64_t mask = (1ull<<56) - 1;
32 uint64_t tmp = a->limb[7] >> 56;
34 for (unsigned int i=7; i>0; i--) {
35 a->limb[i] = (a->limb[i] & mask) + (a->limb[i-1]>>56);
37 a->limb[0] = (a->limb[0] & mask) + tmp;