1use backend::hal::{
 2    api::{ScratchOwnedAlloc, ScratchOwnedBorrow, VecZnxStd, VecZnxSubScalarInplace, ZnxZero},
 3    layouts::{Backend, DataRef, Module, ScalarZnx, ScratchOwned},
 4    oep::{ScratchOwnedAllocImpl, ScratchOwnedBorrowImpl, TakeVecZnxBigImpl, TakeVecZnxDftImpl},
 5};
 6
 7use crate::{GGLWECiphertext, GLWECiphertext, GLWEDecryptFamily, GLWEPlaintext, GLWESecretExec, Infos};
 8
 9impl<D: DataRef> GGLWECiphertext<D> {
10    pub fn assert_noise<B: Backend, DataSk, DataWant>(
11        self,
12        module: &Module<B>,
13        sk: &GLWESecretExec<DataSk, B>,
14        pt_want: &ScalarZnx<DataWant>,
15        max_noise: f64,
16    ) where
17        DataSk: DataRef,
18        DataWant: DataRef,
19        Module<B>: GLWEDecryptFamily<B> + VecZnxStd + VecZnxSubScalarInplace,
20        B: TakeVecZnxDftImpl<B> + TakeVecZnxBigImpl<B> + ScratchOwnedAllocImpl<B> + ScratchOwnedBorrowImpl<B>,
21    {
22        let digits: usize = self.digits();
23        let basek: usize = self.basek();
24        let k: usize = self.k();
25
26        let mut scratch: ScratchOwned<B> = ScratchOwned::alloc(GLWECiphertext::decrypt_scratch_space(
27            module,
28            self.n(),
29            basek,
30            k,
31        ));
32        let mut pt: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::alloc(self.n(), basek, k);
33
34        (0..self.rank_in()).for_each(|col_i| {
35            (0..self.rows()).for_each(|row_i| {
36                self.at(row_i, col_i)
37                    .decrypt(&module, &mut pt, &sk, scratch.borrow());
38
39                module.vec_znx_sub_scalar_inplace(
40                    &mut pt.data,
41                    0,
42                    (digits - 1) + row_i * digits,
43                    pt_want,
44                    col_i,
45                );
46
47                let noise_have: f64 = module.vec_znx_std(basek, &pt.data, 0).log2();
48
49                assert!(
50                    noise_have <= max_noise,
51                    "noise_have: {} > max_noise: {}",
52                    noise_have,
53                    max_noise
54                );
55
56                pt.data.zero();
57            });
58        });
59    }
60}