Bitcoin Core  0.20.99
P2P Digital Currency
field_5x52.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..4, n[i]*2^(i*52)) mod p
14  * where p = 2^256 - 0x1000003D1
15  */
16  uint64_t n[5];
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) | (((uint64_t)(d1) & 0xFFFFFUL) << 32), \
26  ((uint64_t)(d1) >> 20) | (((uint64_t)(d2)) << 12) | (((uint64_t)(d3) & 0xFFUL) << 44), \
27  ((uint64_t)(d3) >> 8) | (((uint64_t)(d4) & 0xFFFFFFFUL) << 24), \
28  ((uint64_t)(d4) >> 28) | (((uint64_t)(d5)) << 4) | (((uint64_t)(d6) & 0xFFFFUL) << 36), \
29  ((uint64_t)(d6) >> 16) | (((uint64_t)(d7)) << 16) \
30 }
31 
32 #ifdef VERIFY
33 #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}
34 #else
35 #define SECP256K1_FE_CONST(d7, d6, d5, d4, d3, d2, d1, d0) {SECP256K1_FE_CONST_INNER((d7), (d6), (d5), (d4), (d3), (d2), (d1), (d0))}
36 #endif
37 
38 typedef struct {
39  uint64_t n[4];
41 
42 #define SECP256K1_FE_STORAGE_CONST(d7, d6, d5, d4, d3, d2, d1, d0) {{ \
43  (d0) | (((uint64_t)(d1)) << 32), \
44  (d2) | (((uint64_t)(d3)) << 32), \
45  (d4) | (((uint64_t)(d5)) << 32), \
46  (d6) | (((uint64_t)(d7)) << 32) \
47 }}
48 
49 #endif /* SECP256K1_FIELD_REPR_H */