FK20 CUDA
fp_isone.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 "fp.cuh"
6 
13 __device__ bool fp_isone(const fp_t &x) {
14  fp_t t;
15  fp_cpy(t, x);
16  fp_reduce6(t);
17 
18  return ((t[5] | t[4] | t[3] | t[2] | t[1] | (1 ^ t[0])) == 0);
19 }
20 
21 // vim: ts=4 et sw=4 si
fp_reduce6
__device__ void fp_reduce6(fp_t &z)
Narrow reduction of a residue modulo p, reducing to the canonical representation.
Definition: fp_reduce6.cu:14
fp_t
uint64_t fp_t[6]
Residue modulo p. Any 384-bit representative of each residue is allowed, and stored as a 6-element li...
Definition: fp.cuh:14
fp_cpy
__device__ __host__ void fp_cpy(fp_t &z, const fp_t &x)
Copy from x into z.
Definition: fp_cpy.cu:14
fp_isone
__device__ bool fp_isone(const fp_t &x)
Checks if the residue x modulo p is congruent to one.
Definition: fp_isone.cu:13