This commit is contained in:
Jean-Philippe Bossuat
2025-01-06 18:05:32 +01:00
parent c69bd6985a
commit 7e4ca491c7
7 changed files with 617 additions and 133 deletions

View File

@@ -314,4 +314,88 @@ pub mod macros {
}
};
}
#[macro_export]
macro_rules! apply_vssv {
($self:expr, $f:expr, $a:expr, $b:expr, $c:expr, $d:expr, $CHUNK:expr) => {
let n: usize = $a.len();
debug_assert!(
$d.len() == n,
"invalid argument d: d.len() = {} != a.len() = {}",
$d.len(),
n
);
debug_assert!(
CHUNK & (CHUNK - 1) == 0,
"invalid CHUNK const: not a power of two"
);
match CHUNK {
8 => {
izip!(
$a.chunks_exact(8),
$d.chunks_exact_mut(8)
)
.for_each(|(a, d)| {
$f(&$self, &a[0], $b, $c, &mut d[0]);
$f(&$self, &a[1], $b, $c, &mut d[1]);
$f(&$self, &a[2], $b, $c, &mut d[2]);
$f(&$self, &a[3], $b, $c, &mut d[3]);
$f(&$self, &a[4], $b, $c, &mut d[4]);
$f(&$self, &a[5], $b, $c, &mut d[5]);
$f(&$self, &a[6], $b, $c, &mut d[6]);
$f(&$self, &a[7], $b, $c, &mut d[7]);
});
let m = n - (n & 7);
izip!($a[m..].iter(), $d[m..].iter_mut()).for_each(
|(a, d)| {
$f(&$self, a, $b, $c, d);
},
);
}
_ => {
izip!($a.iter(), $d.iter_mut()).for_each(|(a, d)| {
$f(&$self, a, $b, $c, d);
});
}
}
};
}
#[macro_export]
macro_rules! apply_ssv {
($self:expr, $f:expr, $a:expr, $b:expr, $c:expr, $CHUNK:expr) => {
let n: usize = $c.len();
debug_assert!(
CHUNK & (CHUNK - 1) == 0,
"invalid CHUNK const: not a power of two"
);
match CHUNK {
8 => {
izip!($c.chunks_exact_mut(8)).for_each(|c| {
$f(&$self, $a, $b, &mut c[0]);
$f(&$self, $a, $b, &mut c[1]);
$f(&$self, $a, $b, &mut c[2]);
$f(&$self, $a, $b, &mut c[3]);
$f(&$self, $a, $b, &mut c[4]);
$f(&$self, $a, $b, &mut c[5]);
$f(&$self, $a, $b, &mut c[6]);
$f(&$self, $a, $b, &mut c[7]);
});
let m = n - (n & 7);
izip!($c[m..].iter_mut()).for_each(|c| {
$f(&$self, $a, $b, c);
});
}
_ => {
izip!($c.iter_mut()).for_each(|c| {
$f(&$self, $a, $b, c);
});
}
}
};
}
}

View File

@@ -74,16 +74,16 @@ pub trait ScalarOperations<O> {
fn sa_add_sb_into_sb<const REDUCE: REDUCEMOD>(&self, a: &O, b: &mut O);
// Assigns a - b to c.
fn sa_sub_sb_into_sc<const REDUCE: REDUCEMOD>(&self, a: &O, b: &O, c: &mut O);
fn sa_sub_sb_into_sc<const SBRANGE: u8, const REDUCE: REDUCEMOD>(&self, a: &O, b: &O, c: &mut O);
// Assigns b - a to b.
fn sa_sub_sb_into_sb<const REDUCE: REDUCEMOD>(&self, a: &O, b: &mut O);
// Assigns a - b to b.
fn sa_sub_sb_into_sb<const SARANGE: u8, const REDUCE: REDUCEMOD>(&self, a: &O, b: &mut O);
// Assigns -a to a.
fn sa_neg_into_sa<const REDUCE: REDUCEMOD>(&self, a: &mut O);
fn sa_neg_into_sa<const SBRANGE: u8, const REDUCE: REDUCEMOD>(&self, a: &mut O);
// Assigns -a to b.
fn sa_neg_into_sb<const REDUCE: REDUCEMOD>(&self, a: &O, b: &mut O);
fn sa_neg_into_sb<const SARANGE: u8, const REDUCE: REDUCEMOD>(&self, a: &O, b: &mut O);
// Assigns a * 2^64 to b.
fn sa_prep_mont_into_sb<const REDUCE: REDUCEMOD>(
@@ -122,8 +122,8 @@ pub trait ScalarOperations<O> {
b: &mut O,
);
// Assigns (a + 2q - b) * c to d.
fn sa_sub_sb_mul_sc_into_sd<const REDUCE: REDUCEMOD>(
// Assigns (a + q - b) * c to d.
fn sa_sub_sb_mul_sc_into_sd<const VBRANGE: u8, const REDUCE: REDUCEMOD>(
&self,
a: &O,
b: &O,
@@ -131,13 +131,30 @@ pub trait ScalarOperations<O> {
d: &mut O,
);
// Assigns (a + 2q - b) * c to b.
fn sa_sub_sb_mul_sc_into_sb<const REDUCE: REDUCEMOD>(
// Assigns (a + q - b) * c to b.
fn sa_sub_sb_mul_sc_into_sb<const SBRANGE: u8, const REDUCE: REDUCEMOD>(
&self,
a: &u64,
c: &barrett::Barrett<u64>,
b: &mut u64,
);
// Assigns (a + b) * c to a.
fn sa_add_sb_mul_sc_into_sa<const REDUCE: REDUCEMOD>(
&self,
b: &u64,
c: &barrett::Barrett<u64>,
a: &mut u64
);
// Assigns (a + b) * c to d.
fn sa_add_sb_mul_sc_into_sd<const REDUCE: REDUCEMOD>(
&self,
a: &u64,
b: &u64,
c: &barrett::Barrett<u64>,
d: &mut u64
);
}
pub trait VectorOperations<O> {
@@ -145,18 +162,18 @@ pub trait VectorOperations<O> {
fn va_reduce_into_va<const CHUNK: usize, const REDUCE: REDUCEMOD>(&self, x: &mut [O]);
// ADD
// Assigns a[i] + b[i] to c[i]
// vec(c) <- vec(a) + vec(b).
fn va_add_vb_into_vc<const CHUNK: usize, const REDUCE: REDUCEMOD>(
&self,
a: &[O],
b: &[O],
c: &mut [O],
va: &[O],
vb: &[O],
vc: &mut [O],
);
// Assigns a[i] + b[i] to b[i]
// vec(b) <- vec(a) + vec(b).
fn va_add_vb_into_vb<const CHUNK: usize, const REDUCE: REDUCEMOD>(&self, a: &[O], b: &mut [O]);
// Assigns a[i] + b to c[i]
// vec(c) <- vec(a) + scalar(b).
fn va_add_sb_into_vc<const CHUNK: usize, const REDUCE: REDUCEMOD>(
&self,
a: &[O],
@@ -164,37 +181,34 @@ pub trait VectorOperations<O> {
c: &mut [O],
);
// Assigns b[i] + a to b[i]
fn sa_add_vb_into_vb<const CHUNK: usize, const REDUCE: REDUCEMOD>(&self, a: &O, b: &mut [O]);
// vec(b) <- vec(b) + scalar(a).
fn va_add_sb_into_va<const CHUNK: usize, const REDUCE: REDUCEMOD>(&self, a: &O, b: &mut [O]);
// SUB
// Assigns a[i] - b[i] to b[i]
fn va_sub_vb_into_vb<const CHUNK: usize, const REDUCE: REDUCEMOD>(&self, a: &[O], b: &mut [O]);
// vec(b) <- vec(a) - vec(b).
fn va_sub_vb_into_vb<const CHUNK: usize, const VBRANGE: u8, const REDUCE: REDUCEMOD>(&self, a: &[O], b: &mut [O]);
// Assigns a[i] - b[i] to c[i]
fn va_sub_vb_into_vc<const CHUNK: usize, const REDUCE: REDUCEMOD>(
// vec(c) <- vec(a) - vec(b).
fn va_sub_vb_into_vc<const CHUNK: usize, const VBRANGE: u8, const REDUCE: REDUCEMOD>(
&self,
a: &[O],
b: &[O],
c: &mut [O],
);
// NEG
// Assigns -a[i] to a[i].
fn va_neg_into_va<const CHUNK: usize, const REDUCE: REDUCEMOD>(&self, a: &mut [O]);
// vec(a) <- -vec(a).
fn va_neg_into_va<const CHUNK: usize, const VARANGE: u8, const REDUCE: REDUCEMOD>(&self, a: &mut [O]);
// Assigns -a[i] to a[i].
fn va_neg_into_vb<const CHUNK: usize, const REDUCE: REDUCEMOD>(&self, a: &[O], b: &mut [O]);
// vec(b) <- -vec(a).
fn va_neg_into_vb<const CHUNK: usize, const VARANGE: u8, const REDUCE: REDUCEMOD>(&self, a: &[O], b: &mut [O]);
// MUL MONTGOMERY
// Assigns a * 2^64 to b.
// vec(b) <- vec(a)
fn va_prep_mont_into_vb<const CHUNK: usize, const REDUCE: REDUCEMOD>(
&self,
a: &[O],
b: &mut [montgomery::Montgomery<O>],
);
// Assigns a[i] * b[i] to c[i].
// vec(c) <- vec(a) * vec(b).
fn va_mont_mul_vb_into_vc<const CHUNK: usize, const REDUCE: REDUCEMOD>(
&self,
a: &[montgomery::Montgomery<O>],
@@ -202,22 +216,21 @@ pub trait VectorOperations<O> {
c: &mut [O],
);
// Assigns a[i] * b[i] to b[i].
// vec(b) <- vec(a) * vec(b).
fn va_mont_mul_vb_into_vb<const CHUNK: usize, const REDUCE: REDUCEMOD>(
&self,
a: &[montgomery::Montgomery<O>],
b: &mut [O],
);
// MUL BARRETT
// Assigns a * b[i] to b[i].
// vec(b) <- vec(b) * scalar(a).
fn sa_barrett_mul_vb_into_vb<const CHUNK: usize, const REDUCE: REDUCEMOD>(
&self,
a: &barrett::Barrett<u64>,
b: &mut [u64],
);
// Assigns a * b[i] to c[i].
// vec(c) <- vec(b) * scalar(a).
fn sa_barrett_mul_vb_into_vc<const CHUNK: usize, const REDUCE: REDUCEMOD>(
&self,
a: &barrett::Barrett<u64>,
@@ -225,9 +238,8 @@ pub trait VectorOperations<O> {
c: &mut [u64],
);
// OTHERS
// Assigns (a[i] + 2q - b[i]) * c to d[i].
fn va_sub_vb_mul_sc_into_vd<const CHUNK: usize, const REDUCE: REDUCEMOD>(
// vec(d) <- (vec(a) + VBRANGE * q - vec(b)) * scalar(c).
fn va_sub_vb_mul_sc_into_vd<const CHUNK: usize, const VBRANGE: u8, const REDUCE: REDUCEMOD>(
&self,
a: &[u64],
b: &[u64],
@@ -235,11 +247,28 @@ pub trait VectorOperations<O> {
d: &mut [u64],
);
// Assigns (a[i] + 2q - b[i]) * c to b[i].
fn va_sub_vb_mul_sc_into_vb<const CHUNK: usize, const REDUCE: REDUCEMOD>(
// vec(b) <- (vec(a) + VBRANGE * q - vec(b)) * scalar(c).
fn va_sub_vb_mul_sc_into_vb<const CHUNK: usize, const VBRANGE: u8, const REDUCE: REDUCEMOD>(
&self,
a: &[u64],
c: &barrett::Barrett<u64>,
b: &mut [u64],
);
// vec(c) <- (vec(a) + scalar(b)) * scalar(c).
fn va_add_sb_mul_sc_into_vd<const CHUNK: usize, const REDUCE: REDUCEMOD>(
&self,
va: &[u64],
sb: &u64,
sc: &barrett::Barrett<u64>,
vd: &mut [u64],
);
// vec(a) <- (vec(a) + scalar(b)) * scalar(c).
fn va_add_sb_mul_sc_into_va<const CHUNK: usize, const REDUCE: REDUCEMOD>(
&self,
sb: &u64,
sc: &barrett::Barrett<u64>,
va: &mut [u64],
);
}

View File

@@ -1,10 +1,9 @@
use crate::modulus::barrett::Barrett;
use crate::modulus::montgomery::Montgomery;
use crate::modulus::prime::Prime;
use crate::modulus::ReduceOnce;
use crate::modulus::REDUCEMOD;
use crate::modulus::{REDUCEMOD, NONE};
use crate::modulus::{ScalarOperations, VectorOperations};
use crate::{apply_sv, apply_svv, apply_v, apply_vsv, apply_vv, apply_vvsv, apply_vvv};
use crate::{apply_sv, apply_svv, apply_v, apply_vsv, apply_vv, apply_vvsv, apply_vvv, apply_ssv, apply_vssv};
use itertools::izip;
impl ScalarOperations<u64> for Prime<u64> {
@@ -33,24 +32,46 @@ impl ScalarOperations<u64> for Prime<u64> {
}
#[inline(always)]
fn sa_sub_sb_into_sc<const REDUCE: REDUCEMOD>(&self, a: &u64, b: &u64, c: &mut u64) {
*c = a.wrapping_add(self.q.wrapping_sub(*b)).reduce_once(self.q);
fn sa_sub_sb_into_sc<const SBRANGE: u8, const REDUCE: REDUCEMOD>(&self, a: &u64, b: &u64, c: &mut u64) {
match SBRANGE{
1 =>{*c = *a + self.q - *b}
2 =>{*c = *a + self.two_q - *b}
4 =>{*c = *a + self.four_q - *b}
_ => unreachable!("invalid SBRANGE argument"),
}
self.sa_reduce_into_sa::<REDUCE>(c)
}
#[inline(always)]
fn sa_sub_sb_into_sb<const REDUCE: REDUCEMOD>(&self, a: &u64, b: &mut u64) {
*b = a.wrapping_add(self.q.wrapping_sub(*b)).reduce_once(self.q);
fn sa_sub_sb_into_sb<const SBRANGE: u8, const REDUCE: REDUCEMOD>(&self, a: &u64, b: &mut u64) {
match SBRANGE{
1 =>{*b = *a + self.q - *b}
2 =>{*b = *a + self.two_q - *b}
4 =>{*b = *a + self.four_q - *b}
_ => unreachable!("invalid SBRANGE argument"),
}
self.sa_reduce_into_sa::<REDUCE>(b)
}
#[inline(always)]
fn sa_neg_into_sa<const REDUCE: REDUCEMOD>(&self, a: &mut u64) {
*a = self.q.wrapping_sub(*a);
fn sa_neg_into_sa<const SBRANGE: u8, const REDUCE: REDUCEMOD>(&self, a: &mut u64) {
match SBRANGE{
1 =>{*a = self.q - *a}
2 =>{*a = self.two_q - *a}
4 =>{*a = self.four_q - *a}
_ => unreachable!("invalid SBRANGE argument"),
}
self.sa_reduce_into_sa::<REDUCE>(a)
}
#[inline(always)]
fn sa_neg_into_sb<const REDUCE: REDUCEMOD>(&self, a: &u64, b: &mut u64) {
*b = self.q.wrapping_sub(*a);
fn sa_neg_into_sb<const SBRANGE: u8, const REDUCE: REDUCEMOD>(&self, a: &u64, b: &mut u64) {
match SBRANGE{
1 =>{*b = self.q - *a}
2 =>{*b = self.two_q - *a}
4 =>{*b = self.four_q - *a}
_ => unreachable!("invalid SBRANGE argument"),
}
self.sa_reduce_into_sa::<REDUCE>(b)
}
@@ -90,27 +111,54 @@ impl ScalarOperations<u64> for Prime<u64> {
}
#[inline(always)]
fn sa_sub_sb_mul_sc_into_sd<const REDUCE: REDUCEMOD>(
fn sa_sub_sb_mul_sc_into_sd<const VBRANGE: u8, const REDUCE: REDUCEMOD>(
&self,
a: &u64,
b: &u64,
c: &Barrett<u64>,
d: &mut u64,
) {
*d = self.two_q.wrapping_sub(*b).wrapping_add(*a);
match VBRANGE{
1 =>{*d = a + self.q - b}
2 =>{*d = a + self.two_q - b}
4 =>{*d = a + self.four_q - b}
_ => unreachable!("invalid SBRANGE argument"),
}
self.barrett.mul_external_assign::<REDUCE>(*c, d);
}
#[inline(always)]
fn sa_sub_sb_mul_sc_into_sb<const REDUCE: REDUCEMOD>(
fn sa_sub_sb_mul_sc_into_sb<const SBRANGE: u8, const REDUCE: REDUCEMOD>(
&self,
a: &u64,
c: &Barrett<u64>,
b: &mut u64,
) {
*b = self.two_q.wrapping_sub(*b).wrapping_add(*a);
self.sa_sub_sb_into_sb::<SBRANGE, NONE>(a, b);
self.barrett.mul_external_assign::<REDUCE>(*c, b);
}
#[inline(always)]
fn sa_add_sb_mul_sc_into_sd<const REDUCE: REDUCEMOD>(
&self,
a: &u64,
b: &u64,
c: &Barrett<u64>,
d: &mut u64
) {
*d = self.barrett.mul_external::<REDUCE>(*c, *a + *b);
}
#[inline(always)]
fn sa_add_sb_mul_sc_into_sa<const REDUCE: REDUCEMOD>(
&self,
b: &u64,
c: &Barrett<u64>,
a: &mut u64
) {
*a = self.barrett.mul_external::<REDUCE>(*c, *a + *b);
}
}
impl VectorOperations<u64> for Prime<u64> {
@@ -145,6 +193,15 @@ impl VectorOperations<u64> for Prime<u64> {
apply_vv!(self, Self::sa_add_sb_into_sb::<REDUCE>, a, b, CHUNK);
}
#[inline(always)]
fn va_add_sb_into_va<const CHUNK: usize, const REDUCE: REDUCEMOD>(
&self,
b: &u64,
a: &mut [u64],
) {
apply_sv!(self, Self::sa_add_sb_into_sb::<REDUCE>, b, a, CHUNK);
}
#[inline(always)]
fn va_add_sb_into_vc<const CHUNK: usize, const REDUCE: REDUCEMOD>(
&self,
@@ -156,45 +213,36 @@ impl VectorOperations<u64> for Prime<u64> {
}
#[inline(always)]
fn sa_add_vb_into_vb<const CHUNK: usize, const REDUCE: REDUCEMOD>(
&self,
a: &u64,
b: &mut [u64],
) {
apply_sv!(self, Self::sa_add_sb_into_sb::<REDUCE>, a, b, CHUNK);
}
#[inline(always)]
fn va_sub_vb_into_vc<const CHUNK: usize, const REDUCE: REDUCEMOD>(
fn va_sub_vb_into_vc<const CHUNK: usize, const VBRANGE: u8, const REDUCE: REDUCEMOD>(
&self,
a: &[u64],
b: &[u64],
c: &mut [u64],
) {
apply_vvv!(self, Self::sa_sub_sb_into_sc::<REDUCE>, a, b, c, CHUNK);
apply_vvv!(self, Self::sa_sub_sb_into_sc::<VBRANGE, REDUCE>, a, b, c, CHUNK);
}
#[inline(always)]
fn va_sub_vb_into_vb<const CHUNK: usize, const REDUCE: REDUCEMOD>(
fn va_sub_vb_into_vb<const CHUNK: usize, const VBRANGE: u8, const REDUCE: REDUCEMOD>(
&self,
a: &[u64],
b: &mut [u64],
) {
apply_vv!(self, Self::sa_sub_sb_into_sb::<REDUCE>, a, b, CHUNK);
apply_vv!(self, Self::sa_sub_sb_into_sb::<VBRANGE, REDUCE>, a, b, CHUNK);
}
#[inline(always)]
fn va_neg_into_va<const CHUNK: usize, const REDUCE: REDUCEMOD>(&self, a: &mut [u64]) {
apply_v!(self, Self::sa_neg_into_sa::<REDUCE>, a, CHUNK);
fn va_neg_into_va<const CHUNK: usize, const VARANGE: u8, const REDUCE: REDUCEMOD>(&self, a: &mut [u64]) {
apply_v!(self, Self::sa_neg_into_sa::<VARANGE, REDUCE>, a, CHUNK);
}
#[inline(always)]
fn va_neg_into_vb<const CHUNK: usize, const REDUCE: REDUCEMOD>(
fn va_neg_into_vb<const CHUNK: usize, const VARANGE: u8, const REDUCE: REDUCEMOD>(
&self,
a: &[u64],
b: &mut [u64],
) {
apply_vv!(self, Self::sa_neg_into_sb::<REDUCE>, a, b, CHUNK);
apply_vv!(self, Self::sa_neg_into_sb::<VARANGE, REDUCE>, a, b, CHUNK);
}
#[inline(always)]
@@ -251,7 +299,7 @@ impl VectorOperations<u64> for Prime<u64> {
apply_sv!(self, Self::sa_barrett_mul_sb_into_sb::<REDUCE>, a, b, CHUNK);
}
fn va_sub_vb_mul_sc_into_vd<const CHUNK: usize, const REDUCE: REDUCEMOD>(
fn va_sub_vb_mul_sc_into_vd<const CHUNK: usize, const VBRANGE: u8, const REDUCE: REDUCEMOD>(
&self,
a: &[u64],
b: &[u64],
@@ -260,7 +308,7 @@ impl VectorOperations<u64> for Prime<u64> {
) {
apply_vvsv!(
self,
Self::sa_sub_sb_mul_sc_into_sd::<REDUCE>,
Self::sa_sub_sb_mul_sc_into_sd::<VBRANGE, REDUCE>,
a,
b,
c,
@@ -269,7 +317,7 @@ impl VectorOperations<u64> for Prime<u64> {
);
}
fn va_sub_vb_mul_sc_into_vb<const CHUNK: usize, const REDUCE: REDUCEMOD>(
fn va_sub_vb_mul_sc_into_vb<const CHUNK: usize, const VBRANGE: u8, const REDUCE: REDUCEMOD>(
&self,
a: &[u64],
b: &Barrett<u64>,
@@ -277,11 +325,47 @@ impl VectorOperations<u64> for Prime<u64> {
) {
apply_vsv!(
self,
Self::sa_sub_sb_mul_sc_into_sb::<REDUCE>,
Self::sa_sub_sb_mul_sc_into_sb::<VBRANGE, REDUCE>,
a,
b,
c,
CHUNK
);
}
// vec(a) <- (vec(a) + scalar(b)) * scalar(c);
fn va_add_sb_mul_sc_into_va<const CHUNK: usize, const REDUCE: REDUCEMOD>(
&self,
b: &u64,
c: &Barrett<u64>,
a: &mut [u64],
) {
apply_ssv!(
self,
Self::sa_add_sb_mul_sc_into_sa::<REDUCE>,
b,
c,
a,
CHUNK
);
}
// vec(a) <- (vec(a) + scalar(b)) * scalar(c);
fn va_add_sb_mul_sc_into_vd<const CHUNK: usize, const REDUCE: REDUCEMOD>(
&self,
a: &[u64],
b: &u64,
c: &Barrett<u64>,
d: &mut [u64],
) {
apply_vssv!(
self,
Self::sa_add_sb_mul_sc_into_sd::<REDUCE>,
a,
b,
c,
d,
CHUNK
);
}
}

View File

@@ -1,5 +1,5 @@
use crate::modulus::barrett::Barrett;
use crate::modulus::ONCE;
use crate::modulus::{NONE, ONCE, BARRETT};
use crate::poly::PolyRNS;
use crate::ring::Ring;
use crate::ring::RingRNS;
@@ -34,8 +34,8 @@ impl RingRNS<u64> {
let (buf_ntt_q_scaling, buf_ntt_qi_scaling) = buf.0.split_at_mut(1);
self.0[level].intt::<false>(a.at(level), &mut buf_ntt_q_scaling[0]);
for (i, r) in self.0[0..level].iter().enumerate() {
r.ntt::<false>(&buf_ntt_q_scaling[0], &mut buf_ntt_qi_scaling[0]);
r.sum_aqqmb_prod_c_scalar_barrett::<ONCE>(
r.ntt::<true>(&buf_ntt_q_scaling[0], &mut buf_ntt_qi_scaling[0]);
r.a_sub_b_mul_c_scalar_barrett::<2, ONCE>(
&buf_ntt_qi_scaling[0],
a.at(i),
&rescaling_constants.0[i],
@@ -44,7 +44,7 @@ impl RingRNS<u64> {
}
} else {
for (i, r) in self.0[0..level].iter().enumerate() {
r.sum_aqqmb_prod_c_scalar_barrett::<ONCE>(
r.a_sub_b_mul_c_scalar_barrett::<2, ONCE>(
a.at(level),
a.at(i),
&rescaling_constants.0[i],
@@ -73,19 +73,19 @@ impl RingRNS<u64> {
if NTT {
let (buf_ntt_q_scaling, buf_ntt_qi_scaling) = buf.0.split_at_mut(1);
self.0[level].intt::<true>(a.at(level), &mut buf_ntt_q_scaling[0]);
self.0[level].intt::<false>(a.at(level), &mut buf_ntt_q_scaling[0]);
for (i, r) in self.0[0..level].iter().enumerate() {
r.ntt::<true>(&buf_ntt_q_scaling[0], &mut buf_ntt_qi_scaling[0]);
r.sum_aqqmb_prod_c_scalar_barrett_inplace::<ONCE>(
r.a_sub_b_mul_c_scalar_barrett_inplace::<2, ONCE>(
&buf_ntt_qi_scaling[0],
&rescaling_constants.0[i],
a.at_mut(i),
);
}
} else {
let (a_i, a_level) = buf.0.split_at_mut(level);
let (a_i, a_level) = a.0.split_at_mut(level);
for (i, r) in self.0[0..level].iter().enumerate() {
r.sum_aqqmb_prod_c_scalar_barrett_inplace::<ONCE>(
r.a_sub_b_mul_c_scalar_barrett_inplace::<2, ONCE>(
&a_level[0],
&rescaling_constants.0[i],
&mut a_i[i],
@@ -102,6 +102,9 @@ impl RingRNS<u64> {
buf: &mut PolyRNS<u64>,
c: &mut PolyRNS<u64>,
) {
println!("{:?}", buf);
debug_assert!(
self.level() <= a.level(),
"invalid input a: self.level()={} > a.level()={}",
@@ -205,26 +208,40 @@ impl RingRNS<u64> {
let r_last: &Ring<u64> = &self.0[level];
let q_level_half: u64 = r_last.modulus.q >> 1;
let rescaling_constants: ScalarRNS<Barrett<u64>> = self.rescaling_constant();
let (buf_ntt_q_scaling, buf_ntt_qi_scaling) = buf.0.split_at_mut(1);
let (buf_q_scaling, buf_qi_scaling) = buf.0.split_at_mut(1);
if NTT {
r_last.intt::<false>(a.at(level), &mut buf_ntt_q_scaling[0]);
r_last.add_scalar_inplace::<ONCE>(&q_level_half, &mut buf_ntt_q_scaling[0]);
r_last.intt::<false>(a.at(level), &mut buf_q_scaling[0]);
r_last.add_scalar_inplace::<ONCE>(&q_level_half, &mut buf_q_scaling[0]);
for (i, r) in self.0[0..level].iter().enumerate() {
r_last.add_scalar::<ONCE>(
&buf_ntt_q_scaling[0],
&q_level_half,
&mut buf_ntt_qi_scaling[0],
r_last.add_scalar::<NONE>(
&buf_q_scaling[0],
&(r.modulus.q - r_last.modulus.barrett.reduce::<BARRETT>(&q_level_half)),
&mut buf_qi_scaling[0],
);
r.ntt_inplace::<false>(&mut buf_ntt_qi_scaling[0]);
r.sum_aqqmb_prod_c_scalar_barrett::<ONCE>(
&buf_ntt_qi_scaling[0],
r.ntt_inplace::<true>(&mut buf_qi_scaling[0]);
r.a_sub_b_mul_c_scalar_barrett::<2, ONCE>(
&buf_qi_scaling[0],
a.at(i),
&rescaling_constants.0[i],
b.at_mut(i),
);
}
} else {
r_last.add_scalar_inplace::<ONCE>(&q_level_half, &mut buf_q_scaling[0]);
for (i, r) in self.0[0..level].iter().enumerate() {
r_last.add_scalar::<NONE>(
&buf_q_scaling[0],
&(r.modulus.q - r_last.modulus.barrett.reduce::<BARRETT>(&q_level_half)),
&mut buf_qi_scaling[0],
);
r.a_sub_b_mul_c_scalar_barrett::<2, ONCE>(
&buf_qi_scaling[0],
a.at(i),
&rescaling_constants.0[i],
b.at_mut(i),
);
}
}
}
@@ -246,24 +263,124 @@ impl RingRNS<u64> {
let r_last: &Ring<u64> = &self.0[level];
let q_level_half: u64 = r_last.modulus.q >> 1;
let rescaling_constants: ScalarRNS<Barrett<u64>> = self.rescaling_constant();
let (buf_ntt_q_scaling, buf_ntt_qi_scaling) = buf.0.split_at_mut(1);
let (buf_q_scaling, buf_qi_scaling) = buf.0.split_at_mut(1);
if NTT {
r_last.intt::<true>(a.at(level), &mut buf_ntt_q_scaling[0]);
r_last.add_scalar_inplace::<ONCE>(&q_level_half, &mut buf_ntt_q_scaling[0]);
r_last.intt::<false>(a.at(level), &mut buf_q_scaling[0]);
r_last.add_scalar_inplace::<ONCE>(&q_level_half, &mut buf_q_scaling[0]);
for (i, r) in self.0[0..level].iter().enumerate() {
r_last.add_scalar::<ONCE>(
&buf_ntt_q_scaling[0],
&q_level_half,
&mut buf_ntt_qi_scaling[0],
r_last.add_scalar::<NONE>(
&buf_q_scaling[0],
&(r.modulus.q - r_last.modulus.barrett.reduce::<BARRETT>(&q_level_half)),
&mut buf_qi_scaling[0],
);
r.ntt::<true>(&buf_ntt_q_scaling[0], &mut buf_ntt_qi_scaling[0]);
r.sum_aqqmb_prod_c_scalar_barrett_inplace::<ONCE>(
&buf_ntt_qi_scaling[0],
r.ntt_inplace::<false>(&mut buf_qi_scaling[0]);
r.a_sub_b_mul_c_scalar_barrett_inplace::<2, ONCE>(
&buf_qi_scaling[0],
&rescaling_constants.0[i],
a.at_mut(i),
);
}
} else {
r_last.add_scalar_inplace::<ONCE>(&q_level_half, &mut buf_q_scaling[0]);
for (i, r) in self.0[0..level].iter().enumerate() {
r_last.add_scalar::<NONE>(
&buf_q_scaling[0],
&(r.modulus.q - r_last.modulus.barrett.reduce::<BARRETT>(&q_level_half)),
&mut buf_qi_scaling[0],
);
r.a_sub_b_mul_c_scalar_barrett_inplace::<2, ONCE>(
&buf_qi_scaling[0],
&rescaling_constants.0[i],
a.at_mut(i),
);
}
}
}
/// Updates b to round(a / prod_{level - nb_moduli}^{level} q[i])
pub fn div_round_by_last_moduli<const NTT: bool>(
&self,
nb_moduli: usize,
a: &PolyRNS<u64>,
buf: &mut PolyRNS<u64>,
c: &mut PolyRNS<u64>,
) {
debug_assert!(
self.level() <= a.level(),
"invalid input a: self.level()={} > a.level()={}",
self.level(),
a.level()
);
debug_assert!(
c.level() >= a.level() - 1,
"invalid input b: b.level()={} < a.level()-1={}",
c.level(),
a.level() - 1
);
debug_assert!(
nb_moduli <= a.level(),
"invalid input nb_moduli: nb_moduli={} > a.level()={}",
nb_moduli,
a.level()
);
if nb_moduli == 0 {
if a != c {
c.copy(a);
}
} else {
if NTT {
self.intt::<false>(a, buf);
(0..nb_moduli).for_each(|i| {
self.at_level(self.level() - i)
.div_round_by_last_modulus_inplace::<false>(
&mut PolyRNS::<u64>::default(),
buf,
)
});
self.at_level(self.level() - nb_moduli).ntt::<false>(buf, c);
} else {
self.div_round_by_last_modulus::<false>(a, buf, c);
(1..nb_moduli).for_each(|i| {
self.at_level(self.level() - i)
.div_round_by_last_modulus_inplace::<false>(buf, c)
});
}
}
}
/// Updates a to round(a / prod_{level - nb_moduli}^{level} q[i])
pub fn div_round_by_last_moduli_inplace<const NTT: bool>(
&self,
nb_moduli: usize,
buf: &mut PolyRNS<u64>,
a: &mut PolyRNS<u64>,
) {
debug_assert!(
self.level() <= a.level(),
"invalid input a: self.level()={} > a.level()={}",
self.level(),
a.level()
);
debug_assert!(
nb_moduli <= a.level(),
"invalid input nb_moduli: nb_moduli={} > a.level()={}",
nb_moduli,
a.level()
);
if NTT {
self.intt::<false>(a, buf);
(0..nb_moduli).for_each(|i| {
self.at_level(self.level() - i)
.div_round_by_last_modulus_inplace::<false>(&mut PolyRNS::<u64>::default(), buf)
});
self.at_level(self.level() - nb_moduli).ntt::<false>(buf, a);
} else {
(0..nb_moduli).for_each(|i| {
self.at_level(self.level() - i)
.div_round_by_last_modulus_inplace::<false>(buf, a)
});
}
}
}

View File

@@ -92,9 +92,9 @@ impl Ring<u64> {
}
#[inline(always)]
pub fn add_scalar_inplace<const REDUCE: REDUCEMOD>(&self, a: &u64, b: &mut Poly<u64>) {
debug_assert!(b.n() == self.n(), "b.n()={} != n={}", b.n(), self.n());
self.modulus.sa_add_vb_into_vb::<CHUNK, REDUCE>(a, &mut b.0);
pub fn add_scalar_inplace<const REDUCE: REDUCEMOD>(&self, b: &u64, a: &mut Poly<u64>) {
debug_assert!(a.n() == self.n(), "a.n()={} != n={}", a.n(), self.n());
self.modulus.va_add_sb_into_va::<CHUNK, REDUCE>(b, &mut a.0);
}
#[inline(always)]
@@ -106,33 +106,47 @@ impl Ring<u64> {
}
#[inline(always)]
pub fn sub_inplace<const REDUCE: REDUCEMOD>(&self, a: &Poly<u64>, b: &mut Poly<u64>) {
debug_assert!(a.n() == self.n(), "a.n()={} != n={}", a.n(), self.n());
debug_assert!(b.n() == self.n(), "b.n()={} != n={}", b.n(), self.n());
self.modulus
.va_sub_vb_into_vb::<CHUNK, REDUCE>(&a.0, &mut b.0);
pub fn add_scalar_then_mul_scalar_barrett_inplace<const REDUCE: REDUCEMOD>(&self, b: &u64, c: &Barrett<u64>, a: &mut Poly<u64>) {
debug_assert!(a.n() == self.n(), "b.n()={} != n={}", a.n(), self.n());
self.modulus.va_add_sb_mul_sc_into_va::<CHUNK, REDUCE>(b, c, &mut a.0);
}
#[inline(always)]
pub fn sub<const REDUCE: REDUCEMOD>(&self, a: &Poly<u64>, b: &Poly<u64>, c: &mut Poly<u64>) {
pub fn add_scalar_then_mul_scalar_barrett<const REDUCE: REDUCEMOD>(&self, a: &Poly<u64>, b: &u64, c: &Barrett<u64>, d: &mut Poly<u64>) {
debug_assert!(a.n() == self.n(), "a.n()={} != n={}", a.n(), self.n());
debug_assert!(d.n() == self.n(), "c.n()={} != n={}", d.n(), self.n());
self.modulus
.va_add_sb_mul_sc_into_vd::<CHUNK, REDUCE>(&a.0, b, c, &mut d.0);
}
#[inline(always)]
pub fn sub_inplace<const BRANGE:u8, const REDUCE: REDUCEMOD>(&self, a: &Poly<u64>, b: &mut Poly<u64>) {
debug_assert!(a.n() == self.n(), "a.n()={} != n={}", a.n(), self.n());
debug_assert!(b.n() == self.n(), "b.n()={} != n={}", b.n(), self.n());
self.modulus
.va_sub_vb_into_vb::<CHUNK, BRANGE, REDUCE>(&a.0, &mut b.0);
}
#[inline(always)]
pub fn sub<const BRANGE:u8, const REDUCE: REDUCEMOD>(&self, a: &Poly<u64>, b: &Poly<u64>, c: &mut Poly<u64>) {
debug_assert!(a.n() == self.n(), "a.n()={} != n={}", a.n(), self.n());
debug_assert!(b.n() == self.n(), "b.n()={} != n={}", b.n(), self.n());
debug_assert!(c.n() == self.n(), "c.n()={} != n={}", c.n(), self.n());
self.modulus
.va_sub_vb_into_vc::<CHUNK, REDUCE>(&a.0, &b.0, &mut c.0);
.va_sub_vb_into_vc::<CHUNK, BRANGE, REDUCE>(&a.0, &b.0, &mut c.0);
}
#[inline(always)]
pub fn neg<const REDUCE: REDUCEMOD>(&self, a: &Poly<u64>, b: &mut Poly<u64>) {
pub fn neg<const ARANGE:u8, const REDUCE: REDUCEMOD>(&self, a: &Poly<u64>, b: &mut Poly<u64>) {
debug_assert!(a.n() == self.n(), "a.n()={} != n={}", a.n(), self.n());
debug_assert!(b.n() == self.n(), "b.n()={} != n={}", b.n(), self.n());
self.modulus.va_neg_into_vb::<CHUNK, REDUCE>(&a.0, &mut b.0);
self.modulus.va_neg_into_vb::<CHUNK, ARANGE, REDUCE>(&a.0, &mut b.0);
}
#[inline(always)]
pub fn neg_inplace<const REDUCE: REDUCEMOD>(&self, a: &mut Poly<u64>) {
pub fn neg_inplace<const ARANGE:u8,const REDUCE: REDUCEMOD>(&self, a: &mut Poly<u64>) {
debug_assert!(a.n() == self.n(), "a.n()={} != n={}", a.n(), self.n());
self.modulus.va_neg_into_va::<CHUNK, REDUCE>(&mut a.0);
self.modulus.va_neg_into_va::<CHUNK, ARANGE, REDUCE>(&mut a.0);
}
#[inline(always)]
@@ -208,7 +222,7 @@ impl Ring<u64> {
}
#[inline(always)]
pub fn sum_aqqmb_prod_c_scalar_barrett<const REDUCE: REDUCEMOD>(
pub fn a_sub_b_mul_c_scalar_barrett<const VBRANGE: u8, const REDUCE: REDUCEMOD>(
&self,
a: &Poly<u64>,
b: &Poly<u64>,
@@ -219,11 +233,11 @@ impl Ring<u64> {
debug_assert!(b.n() == self.n(), "b.n()={} != n={}", b.n(), self.n());
debug_assert!(d.n() == self.n(), "d.n()={} != n={}", d.n(), self.n());
self.modulus
.va_sub_vb_mul_sc_into_vd::<CHUNK, REDUCE>(&a.0, &b.0, c, &mut d.0);
.va_sub_vb_mul_sc_into_vd::<CHUNK, VBRANGE, REDUCE>(&a.0, &b.0, c, &mut d.0);
}
#[inline(always)]
pub fn sum_aqqmb_prod_c_scalar_barrett_inplace<const REDUCE: REDUCEMOD>(
pub fn a_sub_b_mul_c_scalar_barrett_inplace<const BRANGE: u8, const REDUCE: REDUCEMOD>(
&self,
a: &Poly<u64>,
c: &Barrett<u64>,
@@ -232,6 +246,6 @@ impl Ring<u64> {
debug_assert!(a.n() == self.n(), "a.n()={} != n={}", a.n(), self.n());
debug_assert!(b.n() == self.n(), "b.n()={} != n={}", b.n(), self.n());
self.modulus
.va_sub_vb_mul_sc_into_vb::<CHUNK, REDUCE>(&a.0, c, &mut b.0);
.va_sub_vb_mul_sc_into_vb::<CHUNK, BRANGE, REDUCE>(&a.0, c, &mut b.0);
}
}

View File

@@ -172,7 +172,7 @@ impl RingRNS<u64> {
}
#[inline(always)]
pub fn sub<const REDUCE: REDUCEMOD>(
pub fn sub<const BRANGE: u8, const REDUCE: REDUCEMOD>(
&self,
a: &PolyRNS<u64>,
b: &PolyRNS<u64>,
@@ -199,11 +199,11 @@ impl RingRNS<u64> {
self.0
.iter()
.enumerate()
.for_each(|(i, ring)| ring.sub::<REDUCE>(&a.0[i], &b.0[i], &mut c.0[i]));
.for_each(|(i, ring)| ring.sub::<BRANGE, REDUCE>(&a.0[i], &b.0[i], &mut c.0[i]));
}
#[inline(always)]
pub fn sub_inplace<const REDUCE: REDUCEMOD>(&self, a: &PolyRNS<u64>, b: &mut PolyRNS<u64>) {
pub fn sub_inplace<const BRANGE: u8, const REDUCE: REDUCEMOD>(&self, a: &PolyRNS<u64>, b: &mut PolyRNS<u64>) {
debug_assert!(
a.level() >= self.level(),
"a.level()={} < self.level()={}",
@@ -219,11 +219,11 @@ impl RingRNS<u64> {
self.0
.iter()
.enumerate()
.for_each(|(i, ring)| ring.sub_inplace::<REDUCE>(&a.0[i], &mut b.0[i]));
.for_each(|(i, ring)| ring.sub_inplace::<BRANGE, REDUCE>(&a.0[i], &mut b.0[i]));
}
#[inline(always)]
pub fn neg<const REDUCE: REDUCEMOD>(&self, a: &PolyRNS<u64>, b: &mut PolyRNS<u64>) {
pub fn neg<const ARANGE: u8, const REDUCE: REDUCEMOD>(&self, a: &PolyRNS<u64>, b: &mut PolyRNS<u64>) {
debug_assert!(
a.level() >= self.level(),
"a.level()={} < self.level()={}",
@@ -239,11 +239,11 @@ impl RingRNS<u64> {
self.0
.iter()
.enumerate()
.for_each(|(i, ring)| ring.neg::<REDUCE>(&a.0[i], &mut b.0[i]));
.for_each(|(i, ring)| ring.neg::<ARANGE, REDUCE>(&a.0[i], &mut b.0[i]));
}
#[inline(always)]
pub fn neg_inplace<const REDUCE: REDUCEMOD>(&self, a: &mut PolyRNS<u64>) {
pub fn neg_inplace<const ARANGE: u8, const REDUCE: REDUCEMOD>(&self, a: &mut PolyRNS<u64>) {
debug_assert!(
a.level() >= self.level(),
"a.level()={} < self.level()={}",
@@ -253,7 +253,7 @@ impl RingRNS<u64> {
self.0
.iter()
.enumerate()
.for_each(|(i, ring)| ring.neg_inplace::<REDUCE>(&mut a.0[i]));
.for_each(|(i, ring)| ring.neg_inplace::<ARANGE, REDUCE>(&mut a.0[i]));
}
#[inline(always)]

View File

@@ -7,11 +7,17 @@ use sampling::source::Source;
#[test]
fn rescaling_rns_u64() {
let n = 1 << 10;
let moduli: Vec<u64> = vec![0x1fffffffffc80001u64, 0x1fffffffffe00001u64];
let moduli: Vec<u64> = vec![0x1fffffffffc80001u64, 0x1fffffffffe00001u64, 0x1fffffffffb40001, 0x1fffffffff500001];
let ring_rns: RingRNS<u64> = RingRNS::new(n, moduli);
test_div_floor_by_last_modulus::<false>(&ring_rns);
test_div_floor_by_last_modulus::<true>(&ring_rns);
//test_div_floor_by_last_modulus::<false>(&ring_rns);
//test_div_floor_by_last_modulus::<true>(&ring_rns);
test_div_floor_by_last_modulus_inplace::<false>(&ring_rns);
//test_div_floor_by_last_modulus_inplace::<true>(&ring_rns);
//test_div_floor_by_last_moduli::<false>(&ring_rns);
//test_div_floor_by_last_moduli::<true>(&ring_rns);
//test_div_floor_by_last_moduli_inplace::<false>(&ring_rns);
//test_div_floor_by_last_moduli_inplace::<true>(&ring_rns);
}
fn test_div_floor_by_last_modulus<const NTT: bool>(ring_rns: &RingRNS<u64>) {
@@ -58,5 +64,155 @@ fn test_div_floor_by_last_modulus<const NTT: bool>(ring_rns: &RingRNS<u64>) {
}
});
assert!(coeffs_a == coeffs_c);
assert!(coeffs_a == coeffs_c, "test_div_floor_by_last_modulus");
}
fn test_div_floor_by_last_modulus_inplace<const NTT: bool>(ring_rns: &RingRNS<u64>) {
let seed: [u8; 32] = [0; 32];
let mut source: Source = Source::new(seed);
let mut a: PolyRNS<u64> = ring_rns.new_polyrns();
let mut b: PolyRNS<u64> = ring_rns.new_polyrns();
// Allocates a random PolyRNS
ring_rns.fill_uniform(&mut source, &mut a);
// Maps PolyRNS to [BigInt]
let mut coeffs_a: Vec<BigInt> = (0..a.n()).map(|i| BigInt::from(i)).collect();
ring_rns
.at_level(a.level())
.to_bigint_inplace(&a, 1, &mut coeffs_a);
println!("{:?}", &coeffs_a[..8]);
// Performs c = intt(ntt(a) / q_level)
if NTT {
ring_rns.ntt_inplace::<false>(&mut a);
}
ring_rns.div_floor_by_last_modulus_inplace::<NTT>(&mut b, &mut a);
if NTT {
ring_rns.at_level(a.level()-1).intt_inplace::<false>(&mut a);
}
// Exports c to coeffs_c
let mut coeffs_c = vec![BigInt::from(0); a.n()];
ring_rns
.at_level(a.level()-1)
.to_bigint_inplace(&a, 1, &mut coeffs_c);
// Performs floor division on a
let scalar_big = BigInt::from(ring_rns.0[ring_rns.level()].modulus.q);
coeffs_a.iter_mut().for_each(|a| {
// Emulates floor division in [0, q-1] and maps to [-(q-1)/2, (q-1)/2-1]
*a /= &scalar_big;
if a.sign() == Sign::Minus {
*a -= 1;
}
});
println!("{:?}", &coeffs_a[..8]);
println!("{:?}", &coeffs_c[..8]);
assert!(coeffs_a == coeffs_c, "test_div_floor_by_last_modulus_inplace");
}
fn test_div_floor_by_last_moduli<const NTT: bool>(ring_rns: &RingRNS<u64>) {
let seed: [u8; 32] = [0; 32];
let mut source: Source = Source::new(seed);
let nb_moduli: usize = ring_rns.level()-1;
let mut a: PolyRNS<u64> = ring_rns.new_polyrns();
let mut b: PolyRNS<u64> = ring_rns.new_polyrns();
let mut c: PolyRNS<u64> = ring_rns.at_level(ring_rns.level() - 1).new_polyrns();
// Allocates a random PolyRNS
ring_rns.fill_uniform(&mut source, &mut a);
// Maps PolyRNS to [BigInt]
let mut coeffs_a: Vec<BigInt> = (0..a.n()).map(|i| BigInt::from(i)).collect();
ring_rns
.at_level(a.level())
.to_bigint_inplace(&a, 1, &mut coeffs_a);
// Performs c = intt(ntt(a) / q_level)
if NTT {
ring_rns.ntt_inplace::<false>(&mut a);
}
ring_rns.div_floor_by_last_moduli::<NTT>(nb_moduli, &a, &mut b, &mut c);
if NTT {
ring_rns.at_level(c.level()).intt_inplace::<false>(&mut c);
}
// Exports c to coeffs_c
let mut coeffs_c = vec![BigInt::from(0); c.n()];
ring_rns
.at_level(c.level())
.to_bigint_inplace(&c, 1, &mut coeffs_c);
// Performs floor division on a
let mut scalar_big = BigInt::from(1);
(0..nb_moduli).for_each(|i|{scalar_big *= BigInt::from(ring_rns.0[ring_rns.level()].modulus.q)});
coeffs_a.iter_mut().for_each(|a| {
// Emulates floor division in [0, q-1] and maps to [-(q-1)/2, (q-1)/2-1]
*a /= &scalar_big;
if a.sign() == Sign::Minus {
*a -= 1;
}
});
assert!(coeffs_a == coeffs_c, "test_div_floor_by_last_moduli");
}
fn test_div_floor_by_last_moduli_inplace<const NTT: bool>(ring_rns: &RingRNS<u64>) {
let seed: [u8; 32] = [0; 32];
let mut source: Source = Source::new(seed);
let nb_moduli: usize = ring_rns.level()-1;
let mut a: PolyRNS<u64> = ring_rns.new_polyrns();
let mut b: PolyRNS<u64> = ring_rns.new_polyrns();
// Allocates a random PolyRNS
ring_rns.fill_uniform(&mut source, &mut a);
// Maps PolyRNS to [BigInt]
let mut coeffs_a: Vec<BigInt> = (0..a.n()).map(|i| BigInt::from(i)).collect();
ring_rns
.at_level(a.level())
.to_bigint_inplace(&a, 1, &mut coeffs_a);
// Performs c = intt(ntt(a) / q_level)
if NTT {
ring_rns.ntt_inplace::<false>(&mut a);
}
ring_rns.div_floor_by_last_moduli_inplace::<NTT>(nb_moduli, &mut b, &mut a);
if NTT {
ring_rns.at_level(a.level()-nb_moduli).intt_inplace::<false>(&mut a);
}
// Exports c to coeffs_c
let mut coeffs_c = vec![BigInt::from(0); a.n()];
ring_rns
.at_level(a.level()-nb_moduli)
.to_bigint_inplace(&a, 1, &mut coeffs_c);
// Performs floor division on a
let mut scalar_big = BigInt::from(1);
(0..nb_moduli).for_each(|i|{scalar_big *= BigInt::from(ring_rns.0[ring_rns.level()].modulus.q)});
coeffs_a.iter_mut().for_each(|a| {
// Emulates floor division in [0, q-1] and maps to [-(q-1)/2, (q-1)/2-1]
*a /= &scalar_big;
if a.sign() == Sign::Minus {
*a -= 1;
}
});
assert!(coeffs_a == coeffs_c, "test_div_floor_by_last_moduli_inplace");
}