FK20 CUDA
fr_iszero.cu
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1 // bls12_381: Arithmetic for BLS12-381
2 // Copyright 2022-2023 Dag Arne Osvik
3 // Copyright 2022-2023 Luan Cardoso dos Santos
4 
5 #include "fr.cuh"
6 
13 __device__ bool fr_iszero(const fr_t &x) {
14  fr_t t;
15  fr_cpy(t, x);
16  fr_reduce4(t);
17 
18  return ((t[3] | t[2] | t[1] | t[0]) == 0);
19 }
20 
21 // vim: ts=4 et sw=4 si
fr_t
uint64_t fr_t[4]
Subgroup element stored as a 256-bit array (a 4-element little-endian array of uint64_t)....
Definition: fr.cuh:24
fr_cpy
__device__ __host__ void fr_cpy(fr_t &z, const fr_t &x)
Copy from x into z.
Definition: fr_cpy.cu:14
fr_reduce4
__device__ void fr_reduce4(fr_t &z)
Reduced the value in fr_t to the field modulus.
Definition: fr_reduce4.cu:16
fr_iszero
__device__ bool fr_iszero(const fr_t &x)
Checks if the residue x modulo f is congruent to zero.
Definition: fr_iszero.cu:13