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//! Construction of a [`U512`] from eight little-endian `u64` limbs.
use super::U512;
impl U512 {
/// Creates a new [`U512`] from an eight-element array of `u64` limbs in
/// little-endian order: `[w0, w1, w2, w3, w4, w5, w6, w7]` where `w0`
/// is the least significant and `w7` is the most significant.
///
/// Since the internal layout is already little-endian, the array is
/// stored directly without reversal. This is the inverse of
/// [`U512::to_le_limbs`].
///
/// # Examples
///
/// ```
/// use cnfy_uint::u512::U512;
///
/// let value = U512::from_le_limbs([42, 0, 0, 0, 0, 0, 0, 0]);
/// assert_eq!(value, U512::from_be_limbs([0, 0, 0, 0, 0, 0, 0, 42]));
/// ```
#[inline]
pub const fn from_le_limbs(value: [u64; 8]) -> Self {
Self(value)
}
}
#[cfg(test)]
mod ai_tests {
use super::*;
/// Constructing from eight zeros yields a zero value.
#[test]
fn zero() {
assert_eq!(U512::from_le_limbs([0; 8]), U512::ZERO);
}
/// LE limb order is the reverse of BE limb order.
#[test]
fn reverse_of_be() {
let le = U512::from_le_limbs([8, 7, 6, 5, 4, 3, 2, 1]);
let be = U512::from_be_limbs([1, 2, 3, 4, 5, 6, 7, 8]);
assert_eq!(le, be);
}
/// Maximum value fills all eight limbs.
#[test]
fn max_value() {
assert_eq!(U512::from_le_limbs([u64::MAX; 8]), U512::MAX);
}
/// Round-trip with to_le_limbs.
#[test]
fn round_trip() {
let limbs = [0xDEAD, 0xBEEF, 0xCAFE, 0xBABE, 0x42, 0xFF, 0x99, 0x11];
assert_eq!(U512::from_le_limbs(limbs).to_le_limbs(), limbs);
}
}