2 * Copyright 2017-2018 The OpenSSL Project Authors. All Rights Reserved.
3 * Copyright 2014 Cryptography Research, Inc.
5 * Licensed under the OpenSSL license (the "License"). You may not use
6 * this file except in compliance with the License. You can obtain a copy
7 * in the file LICENSE in the source distribution or at
8 * https://www.openssl.org/source/license.html
10 * Originally written by Mike Hamburg
15 #if (defined(__OPTIMIZE__) && !defined(__OPTIMIZE_SIZE__) && !I_HATE_UNROLLED_LOOPS) \
16 || defined(C448_FORCE_UNROLL)
17 # define REPEAT8(_x) _x _x _x _x _x _x _x _x
18 # define FOR_LIMB(_i,_start,_end,_x) do { _i=_start; REPEAT8( if (_i<_end) { _x; } _i++;) } while (0)
20 # define FOR_LIMB(_i,_start,_end,_x) do { for (_i=_start; _i<_end; _i++) _x; } while (0)
23 void gf_mul(gf_s * RESTRICT cs, const gf as, const gf bs)
25 const uint32_t *a = as->limb, *b = bs->limb;
26 uint32_t *c = cs->limb;
27 uint64_t accum0 = 0, accum1 = 0, accum2 = 0;
28 uint32_t mask = (1 << 28) - 1;
29 uint32_t aa[8], bb[8];
32 for (i = 0; i < 8; i++) {
33 aa[i] = a[i] + a[i + 8];
34 bb[i] = b[i] + b[i + 8];
39 FOR_LIMB(i, 0, j + 1, {
40 accum2 += widemul(a[j - i], b[i]);
41 accum1 += widemul(aa[j - i], bb[i]);
42 accum0 += widemul(a[8 + j - i], b[8 + i]);
44 ); accum1 -= accum2; accum0 += accum2;
46 FOR_LIMB(i, j + 1, 8, {
48 widemul(a[8 + j - i], b[i]);
50 widemul(aa[8 + j - i],
52 accum1 += widemul(a[16 + j - i], b[8 + i]);
57 c[j] = ((uint32_t)(accum0)) & mask;
58 c[j + 8] = ((uint32_t)(accum1)) & mask;
59 accum0 >>= 28; accum1 >>= 28;
65 c[8] = ((uint32_t)(accum0)) & mask;
66 c[0] = ((uint32_t)(accum1)) & mask;
70 c[9] += ((uint32_t)(accum0));
71 c[1] += ((uint32_t)(accum1));
74 void gf_mulw_unsigned(gf_s * RESTRICT cs, const gf as, uint32_t b)
76 const uint32_t *a = as->limb;
77 uint32_t *c = cs->limb;
78 uint64_t accum0 = 0, accum8 = 0;
79 uint32_t mask = (1 << 28) - 1;
85 accum0 += widemul(b, a[i]); accum8 += widemul(b, a[i + 8]);
86 c[i] = accum0 & mask; accum0 >>= 28;
87 c[i + 8] = accum8 & mask; accum8 >>= 28;
90 accum0 += accum8 + c[8];
91 c[8] = ((uint32_t)accum0) & mask;
92 c[9] += (uint32_t)(accum0 >> 28);
95 c[0] = ((uint32_t)accum8) & mask;
96 c[1] += (uint32_t)(accum8 >> 28);
99 void gf_sqr(gf_s * RESTRICT cs, const gf as)
101 gf_mul(cs, as, as); /* Performs better with a dedicated square */