github.com/ethereum/go-ethereum@v1.16.1/crypto/secp256k1/libsecp256k1/src/int128_native_impl.h (about)

     1  #ifndef SECP256K1_INT128_NATIVE_IMPL_H
     2  #define SECP256K1_INT128_NATIVE_IMPL_H
     3  
     4  #include "int128.h"
     5  #include "util.h"
     6  
     7  static SECP256K1_INLINE void secp256k1_u128_load(secp256k1_uint128 *r, uint64_t hi, uint64_t lo) {
     8      *r = (((uint128_t)hi) << 64) + lo;
     9  }
    10  
    11  static SECP256K1_INLINE void secp256k1_u128_mul(secp256k1_uint128 *r, uint64_t a, uint64_t b) {
    12     *r = (uint128_t)a * b;
    13  }
    14  
    15  static SECP256K1_INLINE void secp256k1_u128_accum_mul(secp256k1_uint128 *r, uint64_t a, uint64_t b) {
    16     *r += (uint128_t)a * b;
    17  }
    18  
    19  static SECP256K1_INLINE void secp256k1_u128_accum_u64(secp256k1_uint128 *r, uint64_t a) {
    20     *r += a;
    21  }
    22  
    23  static SECP256K1_INLINE void secp256k1_u128_rshift(secp256k1_uint128 *r, unsigned int n) {
    24     VERIFY_CHECK(n < 128);
    25     *r >>= n;
    26  }
    27  
    28  static SECP256K1_INLINE uint64_t secp256k1_u128_to_u64(const secp256k1_uint128 *a) {
    29     return (uint64_t)(*a);
    30  }
    31  
    32  static SECP256K1_INLINE uint64_t secp256k1_u128_hi_u64(const secp256k1_uint128 *a) {
    33     return (uint64_t)(*a >> 64);
    34  }
    35  
    36  static SECP256K1_INLINE void secp256k1_u128_from_u64(secp256k1_uint128 *r, uint64_t a) {
    37     *r = a;
    38  }
    39  
    40  static SECP256K1_INLINE int secp256k1_u128_check_bits(const secp256k1_uint128 *r, unsigned int n) {
    41     VERIFY_CHECK(n < 128);
    42     return (*r >> n == 0);
    43  }
    44  
    45  static SECP256K1_INLINE void secp256k1_i128_load(secp256k1_int128 *r, int64_t hi, uint64_t lo) {
    46      *r = (((uint128_t)(uint64_t)hi) << 64) + lo;
    47  }
    48  
    49  static SECP256K1_INLINE void secp256k1_i128_mul(secp256k1_int128 *r, int64_t a, int64_t b) {
    50     *r = (int128_t)a * b;
    51  }
    52  
    53  static SECP256K1_INLINE void secp256k1_i128_accum_mul(secp256k1_int128 *r, int64_t a, int64_t b) {
    54     int128_t ab = (int128_t)a * b;
    55     VERIFY_CHECK(0 <= ab ? *r <= INT128_MAX - ab : INT128_MIN - ab <= *r);
    56     *r += ab;
    57  }
    58  
    59  static SECP256K1_INLINE void secp256k1_i128_det(secp256k1_int128 *r, int64_t a, int64_t b, int64_t c, int64_t d) {
    60     int128_t ad = (int128_t)a * d;
    61     int128_t bc = (int128_t)b * c;
    62     VERIFY_CHECK(0 <= bc ? INT128_MIN + bc <= ad : ad <= INT128_MAX + bc);
    63     *r = ad - bc;
    64  }
    65  
    66  static SECP256K1_INLINE void secp256k1_i128_rshift(secp256k1_int128 *r, unsigned int n) {
    67     VERIFY_CHECK(n < 128);
    68     *r >>= n;
    69  }
    70  
    71  static SECP256K1_INLINE uint64_t secp256k1_i128_to_u64(const secp256k1_int128 *a) {
    72     return (uint64_t)*a;
    73  }
    74  
    75  static SECP256K1_INLINE int64_t secp256k1_i128_to_i64(const secp256k1_int128 *a) {
    76     VERIFY_CHECK(INT64_MIN <= *a && *a <= INT64_MAX);
    77     return *a;
    78  }
    79  
    80  static SECP256K1_INLINE void secp256k1_i128_from_i64(secp256k1_int128 *r, int64_t a) {
    81     *r = a;
    82  }
    83  
    84  static SECP256K1_INLINE int secp256k1_i128_eq_var(const secp256k1_int128 *a, const secp256k1_int128 *b) {
    85     return *a == *b;
    86  }
    87  
    88  static SECP256K1_INLINE int secp256k1_i128_check_pow2(const secp256k1_int128 *r, unsigned int n, int sign) {
    89     VERIFY_CHECK(n < 127);
    90     VERIFY_CHECK(sign == 1 || sign == -1);
    91     return (*r == (int128_t)((uint128_t)sign << n));
    92  }
    93  
    94  #endif