1 /* Copyright (c) 2014-2016 Cryptography Research, Inc.
2 * Released under the MIT License. See LICENSE.txt for license information.
6 #define LIMB(x) (x##ull)&((1ull<<28)-1), (x##ull)>>28
7 #define FIELD_LITERAL(a,b,c,d,e,f,g,h) \
8 {{LIMB(a),LIMB(b),LIMB(c),LIMB(d),LIMB(e),LIMB(f),LIMB(g),LIMB(h)}}
10 #define LIMB_PLACE_VALUE(i) 28
12 void gf_add_RAW (gf out, const gf a, const gf b) {
13 for (unsigned int i=0; i<sizeof(*out)/sizeof(out->limb[0]); i++) {
14 out->limb[i] = a->limb[i] + b->limb[i];
18 void gf_sub_RAW (gf out, const gf a, const gf b) {
19 for (unsigned int i=0; i<sizeof(*out)/sizeof(out->limb[0]); i++) {
20 out->limb[i] = a->limb[i] - b->limb[i];
24 void gf_bias (gf a, int amt) {
25 uint32_t co1 = ((1ull<<28)-1)*amt, co2 = co1-amt;
26 for (unsigned int i=0; i<sizeof(*a)/sizeof(a->limb[0]); i++) {
27 a->limb[i] += (i==sizeof(*a)/sizeof(a->limb[0])/2) ? co2 : co1;
31 void gf_weak_reduce (gf a) {
32 uint32_t mask = (1ull<<28) - 1;
33 uint32_t tmp = a->limb[15] >> 28;
35 for (unsigned int i=15; i>0; i--) {
36 a->limb[i] = (a->limb[i] & mask) + (a->limb[i-1]>>28);
38 a->limb[0] = (a->limb[0] & mask) + tmp;