logos-storage/plonky2
1
0
Fork 0
mirror of https://github.com/logos-storage/plonky2.git synced 2026-01-03 14:23:07 +00:00
Code Issues Packages Projects Releases Wiki Activity

Keccak generation tweak

Browse Source
This commit is contained in:
Daniel Lubarov 2022-08-25 23:13:13 -07:00
parent 50c9638b55
commit 66a3999679
1 changed files with 6 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
evm/src/keccak/keccak_stark.rs
View File

@ -134,9 +134,10 @@ impl<F: RichField + Extendable<D>, const D: usize> KeccakStark<F, D> {
}
}
// Populate A'.
// A'[x, y] = xor(A[x, y], D[x])
// = xor(A[x, y], C[x - 1], ROT(C[x + 1], 1))
// Populate A'. To avoid shifting indices, we rewrite
// A'[x, y, z] = xor(A[x, y, z], C[x - 1, z], C[x + 1, z - 1])
// as
// A'[x, y, z] = xor(A[x, y, z], C[x, z], C'[x, z]).
for x in 0..5 {
for y in 0..5 {
for z in 0..64 {
@ -145,11 +146,8 @@ impl<F: RichField + Extendable<D>, const D: usize> KeccakStark<F, D> {
let reg_a_limb = reg_a(x, y) + is_high_limb;
let a_limb = row[reg_a_limb].to_canonical_u64() as u32;
let a_bit = F::from_bool(((a_limb >> bit_in_limb) & 1) != 0);
row[reg_a_prime(x, y, z)] = xor([
a_bit,
row[reg_c((x + 4) % 5, z)],
row[reg_c((x + 1) % 5, (z + 64 - 1) % 64)],
]);
row[reg_a_prime(x, y, z)] =
xor([a_bit, row[reg_c(x, z)], row[reg_c_prime(x, z)]]);
}
}
}