Bitcoin Core  0.19.99
P2P Digital Currency
field_10x26.h
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1 /**********************************************************************
2  * Copyright (c) 2013, 2014 Pieter Wuille *
3  * Distributed under the MIT software license, see the accompanying *
4  * file COPYING or http://www.opensource.org/licenses/mit-license.php.*
5  **********************************************************************/
6 
7 #ifndef SECP256K1_FIELD_REPR_H
8 #define SECP256K1_FIELD_REPR_H
9 
10 #include <stdint.h>
11 
12 typedef struct {
13  /* X = sum(i=0..9, n[i]*2^(i*26)) mod p
14  * where p = 2^256 - 0x1000003D1
15  */
16  uint32_t n[10];
17 #ifdef VERIFY
18  int magnitude;
19  int normalized;
20 #endif
21 } secp256k1_fe;
22 
23 /* Unpacks a constant into a overlapping multi-limbed FE element. */
24 #define SECP256K1_FE_CONST_INNER(d7, d6, d5, d4, d3, d2, d1, d0) { \
25  (d0) & 0x3FFFFFFUL, \
26  (((uint32_t)d0) >> 26) | (((uint32_t)(d1) & 0xFFFFFUL) << 6), \
27  (((uint32_t)d1) >> 20) | (((uint32_t)(d2) & 0x3FFFUL) << 12), \
28  (((uint32_t)d2) >> 14) | (((uint32_t)(d3) & 0xFFUL) << 18), \
29  (((uint32_t)d3) >> 8) | (((uint32_t)(d4) & 0x3UL) << 24), \
30  (((uint32_t)d4) >> 2) & 0x3FFFFFFUL, \
31  (((uint32_t)d4) >> 28) | (((uint32_t)(d5) & 0x3FFFFFUL) << 4), \
32  (((uint32_t)d5) >> 22) | (((uint32_t)(d6) & 0xFFFFUL) << 10), \
33  (((uint32_t)d6) >> 16) | (((uint32_t)(d7) & 0x3FFUL) << 16), \
34  (((uint32_t)d7) >> 10) \
35 }
36 
37 #ifdef VERIFY
38 #define SECP256K1_FE_CONST(d7, d6, d5, d4, d3, d2, d1, d0) {SECP256K1_FE_CONST_INNER((d7), (d6), (d5), (d4), (d3), (d2), (d1), (d0)), 1, 1}
39 #else
40 #define SECP256K1_FE_CONST(d7, d6, d5, d4, d3, d2, d1, d0) {SECP256K1_FE_CONST_INNER((d7), (d6), (d5), (d4), (d3), (d2), (d1), (d0))}
41 #endif
42 
43 typedef struct {
44  uint32_t n[8];
46 
47 #define SECP256K1_FE_STORAGE_CONST(d7, d6, d5, d4, d3, d2, d1, d0) {{ (d0), (d1), (d2), (d3), (d4), (d5), (d6), (d7) }}
48 #define SECP256K1_FE_STORAGE_CONST_GET(d) d.n[7], d.n[6], d.n[5], d.n[4],d.n[3], d.n[2], d.n[1], d.n[0]
49 
50 #endif /* SECP256K1_FIELD_REPR_H */