Bitcoin Core  26.99.0
P2P Digital Currency
int128.h
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1 #ifndef SECP256K1_INT128_H
2 #define SECP256K1_INT128_H
3 
4 #include "util.h"
5 
6 #if defined(SECP256K1_WIDEMUL_INT128)
7 # if defined(SECP256K1_INT128_NATIVE)
8 # include "int128_native.h"
9 # elif defined(SECP256K1_INT128_STRUCT)
10 # include "int128_struct.h"
11 # else
12 # error "Please select int128 implementation"
13 # endif
14 
15 /* Construct an unsigned 128-bit value from a high and a low 64-bit value. */
16 static SECP256K1_INLINE void secp256k1_u128_load(secp256k1_uint128 *r, uint64_t hi, uint64_t lo);
17 
18 /* Multiply two unsigned 64-bit values a and b and write the result to r. */
19 static SECP256K1_INLINE void secp256k1_u128_mul(secp256k1_uint128 *r, uint64_t a, uint64_t b);
20 
21 /* Multiply two unsigned 64-bit values a and b and add the result to r.
22  * The final result is taken modulo 2^128.
23  */
24 static SECP256K1_INLINE void secp256k1_u128_accum_mul(secp256k1_uint128 *r, uint64_t a, uint64_t b);
25 
26 /* Add an unsigned 64-bit value a to r.
27  * The final result is taken modulo 2^128.
28  */
30 
31 /* Unsigned (logical) right shift.
32  * Non-constant time in n.
33  */
34 static SECP256K1_INLINE void secp256k1_u128_rshift(secp256k1_uint128 *r, unsigned int n);
35 
36 /* Return the low 64-bits of a 128-bit value as an unsigned 64-bit value. */
38 
39 /* Return the high 64-bits of a 128-bit value as an unsigned 64-bit value. */
41 
42 /* Write an unsigned 64-bit value to r. */
44 
45 /* Tests if r is strictly less than to 2^n.
46  * n must be strictly less than 128.
47  */
48 static SECP256K1_INLINE int secp256k1_u128_check_bits(const secp256k1_uint128 *r, unsigned int n);
49 
50 /* Construct an signed 128-bit value from a high and a low 64-bit value. */
51 static SECP256K1_INLINE void secp256k1_i128_load(secp256k1_int128 *r, int64_t hi, uint64_t lo);
52 
53 /* Multiply two signed 64-bit values a and b and write the result to r. */
54 static SECP256K1_INLINE void secp256k1_i128_mul(secp256k1_int128 *r, int64_t a, int64_t b);
55 
56 /* Multiply two signed 64-bit values a and b and add the result to r.
57  * Overflow or underflow from the addition is undefined behaviour.
58  */
59 static SECP256K1_INLINE void secp256k1_i128_accum_mul(secp256k1_int128 *r, int64_t a, int64_t b);
60 
61 /* Compute a*d - b*c from signed 64-bit values and write the result to r. */
62 static SECP256K1_INLINE void secp256k1_i128_det(secp256k1_int128 *r, int64_t a, int64_t b, int64_t c, int64_t d);
63 
64 /* Signed (arithmetic) right shift.
65  * Non-constant time in b.
66  */
67 static SECP256K1_INLINE void secp256k1_i128_rshift(secp256k1_int128 *r, unsigned int b);
68 
69 /* Return the input value modulo 2^64. */
71 
72 /* Return the value as a signed 64-bit value.
73  * Requires the input to be between INT64_MIN and INT64_MAX.
74  */
76 
77 /* Write a signed 64-bit value to r. */
79 
80 /* Compare two 128-bit values for equality. */
82 
83 /* Tests if r is equal to sign*2^n (sign must be 1 or -1).
84  * n must be strictly less than 127.
85  */
86 static SECP256K1_INLINE int secp256k1_i128_check_pow2(const secp256k1_int128 *r, unsigned int n, int sign);
87 
88 #endif
89 
90 #endif
int128_t secp256k1_int128
Definition: int128_native.h:17
static SECP256K1_INLINE void secp256k1_i128_load(secp256k1_int128 *r, int64_t hi, uint64_t lo)
static SECP256K1_INLINE void secp256k1_i128_det(secp256k1_int128 *r, int64_t a, int64_t b, int64_t c, int64_t d)
static SECP256K1_INLINE int secp256k1_u128_check_bits(const secp256k1_uint128 *r, unsigned int n)
static SECP256K1_INLINE void secp256k1_i128_rshift(secp256k1_int128 *r, unsigned int n)
static SECP256K1_INLINE uint64_t secp256k1_u128_hi_u64(const secp256k1_uint128 *a)
static SECP256K1_INLINE uint64_t secp256k1_i128_to_u64(const secp256k1_int128 *a)
static SECP256K1_INLINE void secp256k1_i128_from_i64(secp256k1_int128 *r, int64_t a)
static SECP256K1_INLINE void secp256k1_u128_from_u64(secp256k1_uint128 *r, uint64_t a)
static SECP256K1_INLINE int secp256k1_i128_eq_var(const secp256k1_int128 *a, const secp256k1_int128 *b)
static SECP256K1_INLINE int64_t secp256k1_i128_to_i64(const secp256k1_int128 *a)
static SECP256K1_INLINE void secp256k1_i128_mul(secp256k1_int128 *r, int64_t a, int64_t b)
static SECP256K1_INLINE void secp256k1_u128_rshift(secp256k1_uint128 *r, unsigned int n)
static SECP256K1_INLINE int secp256k1_i128_check_pow2(const secp256k1_int128 *r, unsigned int n, int sign)
static SECP256K1_INLINE void secp256k1_u128_accum_u64(secp256k1_uint128 *r, uint64_t a)
static SECP256K1_INLINE void secp256k1_i128_accum_mul(secp256k1_int128 *r, int64_t a, int64_t b)
static SECP256K1_INLINE void secp256k1_u128_accum_mul(secp256k1_uint128 *r, uint64_t a, uint64_t b)
static SECP256K1_INLINE void secp256k1_u128_load(secp256k1_uint128 *r, uint64_t hi, uint64_t lo)
static SECP256K1_INLINE void secp256k1_u128_mul(secp256k1_uint128 *r, uint64_t a, uint64_t b)
static SECP256K1_INLINE uint64_t secp256k1_u128_to_u64(const secp256k1_uint128 *a)
#define SECP256K1_INLINE
Definition: util.h:48