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macro_rules! bigint_impl {
($name:ident, $num_limbs:expr) => {
#[derive(Copy, Clone, PartialEq, Eq, Debug, Default, Hash)]
pub struct $name(pub [u64; $num_limbs]);
impl $name {
pub fn new(value: [u64; $num_limbs]) -> Self {
$name(value)
}
}
impl BigInteger for $name {
#[inline]
fn add_nocarry(&mut self, other: &Self) -> bool {
let mut carry = 0;
for (a, b) in self.0.iter_mut().zip(other.0.iter()) {
*a = arithmetic::adc(*a, *b, &mut carry);
}
carry != 0
}
#[inline]
fn sub_noborrow(&mut self, other: &Self) -> bool {
let mut borrow = 0;
for (a, b) in self.0.iter_mut().zip(other.0.iter()) {
*a = arithmetic::sbb(*a, *b, &mut borrow);
}
borrow != 0
}
#[inline]
fn mul2(&mut self) {
let mut last = 0;
for i in &mut self.0 {
let tmp = *i >> 63;
*i <<= 1;
*i |= last;
last = tmp;
}
}
#[inline]
fn muln(&mut self, mut n: u32) {
if n >= 64 * $num_limbs {
*self = Self::from(0);
return;
}
while n >= 64 {
let mut t = 0;
for i in &mut self.0 {
::std::mem::swap(&mut t, i);
}
n -= 64;
}
if n > 0 {
let mut t = 0;
for i in &mut self.0 {
let t2 = *i >> (64 - n);
*i <<= n;
*i |= t;
t = t2;
}
}
}
#[inline]
fn div2(&mut self) {
let mut t = 0;
for i in self.0.iter_mut().rev() {
let t2 = *i << 63;
*i >>= 1;
*i |= t;
t = t2;
}
}
#[inline]
fn divn(&mut self, mut n: u32) {
if n >= 64 * $num_limbs {
*self = Self::from(0);
return;
}
while n >= 64 {
let mut t = 0;
for i in self.0.iter_mut().rev() {
::std::mem::swap(&mut t, i);
}
n -= 64;
}
if n > 0 {
let mut t = 0;
for i in self.0.iter_mut().rev() {
let t2 = *i << (64 - n);
*i >>= n;
*i |= t;
t = t2;
}
}
}
#[inline]
fn is_odd(&self) -> bool {
self.0[0] & 1 == 1
}
#[inline]
fn is_even(&self) -> bool {
!self.is_odd()
}
#[inline]
fn is_zero(&self) -> bool {
self.0.iter().all(|&e| e == 0)
}
#[inline]
fn num_bits(&self) -> u32 {
let mut ret = $num_limbs * 64;
for i in self.0.iter().rev() {
let leading = i.leading_zeros();
ret -= leading;
if leading != 64 {
break;
}
}
ret
}
#[inline]
fn get_bit(&self, i: usize) -> bool {
if i >= 64 * $num_limbs {
false
} else {
let limb = i / 64;
let bit = i - (64 * limb);
(self.0[limb] & (1 << bit)) != 0
}
}
#[inline]
fn from_bits(bits: &[bool]) -> Self {
let mut res = Self::default();
let mut acc: u64 = 0;
let mut bits = bits.to_vec();
bits.reverse();
for (i, bits64) in bits.chunks(64).enumerate() {
for bit in bits64.iter().rev() {
acc <<= 1;
acc += *bit as u64;
}
res.0[i] = acc;
acc = 0;
}
res
}
#[inline]
fn to_bits(&self) -> Vec<bool> {
let mut res = Vec::with_capacity(256);
for b in BitIterator::new(self.0) {
res.push(b);
}
res
}
#[inline]
fn find_wnaf(&self) -> Vec<i64> {
let mut res = vec![];
let mut e = self.clone();
while !e.is_zero() {
let z: i64;
if e.is_odd() {
z = 2 - (e.0[0] % 4) as i64;
if z >= 0 {
e.sub_noborrow(&Self::from(z as u64));
} else {
e.add_nocarry(&Self::from((-z) as u64));
}
} else {
z = 0;
}
res.push(z);
e.div2();
}
res
}
}
impl ToBytes for $name {
#[inline]
fn write<W: Write>(&self, writer: W) -> IoResult<()> {
self.0.write(writer)
}
}
impl FromBytes for $name {
#[inline]
fn read<R: Read>(reader: R) -> IoResult<Self> {
<[u64; $num_limbs]>::read(reader).map(Self::new)
}
}
impl Display for $name {
fn fmt(&self, f: &mut ::std::fmt::Formatter<'_>) -> ::std::fmt::Result {
for i in self.0.iter().rev() {
write!(f, "{:016X}", *i)?;
}
Ok(())
}
}
impl Ord for $name {
#[inline]
fn cmp(&self, other: &Self) -> ::std::cmp::Ordering {
for (a, b) in self.0.iter().rev().zip(other.0.iter().rev()) {
if a < b {
return ::std::cmp::Ordering::Less;
} else if a > b {
return ::std::cmp::Ordering::Greater;
}
}
::std::cmp::Ordering::Equal
}
}
impl PartialOrd for $name {
#[inline]
fn partial_cmp(&self, other: &Self) -> Option<::std::cmp::Ordering> {
Some(self.cmp(other))
}
}
impl Distribution<$name> for Standard {
fn sample<R: Rng + ?Sized>(&self, rng: &mut R) -> $name {
$name(rng.gen())
}
}
impl AsMut<[u64]> for $name {
#[inline]
fn as_mut(&mut self) -> &mut [u64] {
&mut self.0
}
}
impl AsRef<[u64]> for $name {
#[inline]
fn as_ref(&self) -> &[u64] {
&self.0
}
}
impl From<u64> for $name {
#[inline]
fn from(val: u64) -> $name {
let mut repr = Self::default();
repr.0[0] = val;
repr
}
}
};
}