mirror of
https://github.com/oxen-io/lokinet.git
synced 2024-11-11 07:10:36 +00:00
59 lines
1.4 KiB
C
59 lines
1.4 KiB
C
|
/*
|
||
|
|
This file is adapted from amd64-51/fe25519_invert.c:
|
||
|
|
Loops of squares are replaced by nsquares for better performance.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include "fe51.h"
|
||
|
|
|
||
|
|
#ifdef HAVE_AVX_ASM
|
||
|
|
|
||
|
|
#define fe51_square(x, y) fe51_nsquare(x, y, 1)
|
||
|
|
|
||
|
|
void
|
||
|
|
fe51_invert(fe51 *r, const fe51 *x)
|
||
|
|
{
|
||
|
|
fe51 z2;
|
||
|
|
fe51 z9;
|
||
|
|
fe51 z11;
|
||
|
|
fe51 z2_5_0;
|
||
|
|
fe51 z2_10_0;
|
||
|
|
fe51 z2_20_0;
|
||
|
|
fe51 z2_50_0;
|
||
|
|
fe51 z2_100_0;
|
||
|
|
fe51 t;
|
||
|
|
|
||
|
|
/* 2 */ fe51_square(&z2,x);
|
||
|
|
/* 4 */ fe51_square(&t,&z2);
|
||
|
|
/* 8 */ fe51_square(&t,&t);
|
||
|
|
/* 9 */ fe51_mul(&z9,&t,x);
|
||
|
|
/* 11 */ fe51_mul(&z11,&z9,&z2);
|
||
|
|
/* 22 */ fe51_square(&t,&z11);
|
||
|
|
/* 2^5 - 2^0 = 31 */ fe51_mul(&z2_5_0,&t,&z9);
|
||
|
|
|
||
|
|
/* 2^10 - 2^5 */ fe51_nsquare(&t,&z2_5_0, 5);
|
||
|
|
/* 2^10 - 2^0 */ fe51_mul(&z2_10_0,&t,&z2_5_0);
|
||
|
|
|
||
|
|
/* 2^20 - 2^10 */ fe51_nsquare(&t,&z2_10_0, 10);
|
||
|
|
/* 2^20 - 2^0 */ fe51_mul(&z2_20_0,&t,&z2_10_0);
|
||
|
|
|
||
|
|
/* 2^40 - 2^20 */ fe51_nsquare(&t,&z2_20_0, 20);
|
||
|
|
/* 2^40 - 2^0 */ fe51_mul(&t,&t,&z2_20_0);
|
||
|
|
|
||
|
|
/* 2^50 - 2^10 */ fe51_nsquare(&t,&t,10);
|
||
|
|
/* 2^50 - 2^0 */ fe51_mul(&z2_50_0,&t,&z2_10_0);
|
||
|
|
|
||
|
|
/* 2^100 - 2^50 */ fe51_nsquare(&t,&z2_50_0, 50);
|
||
|
|
/* 2^100 - 2^0 */ fe51_mul(&z2_100_0,&t,&z2_50_0);
|
||
|
|
|
||
|
|
/* 2^200 - 2^100 */ fe51_nsquare(&t,&z2_100_0, 100);
|
||
|
|
/* 2^200 - 2^0 */ fe51_mul(&t,&t,&z2_100_0);
|
||
|
|
|
||
|
|
/* 2^250 - 2^50 */ fe51_nsquare(&t,&t, 50);
|
||
|
|
/* 2^250 - 2^0 */ fe51_mul(&t,&t,&z2_50_0);
|
||
|
|
|
||
|
|
/* 2^255 - 2^5 */ fe51_nsquare(&t,&t,5);
|
||
|
|
/* 2^255 - 21 */ fe51_mul(r,&t,&z11);
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif
|