1 files changed, 70 insertions, 0 deletions
diff --git a/vendor/crypto-bigint/src/uint/concat.rs b/vendor/crypto-bigint/src/uint/concat.rs
new file mode 100644
index 0000000..dde5242
--- /dev/null
+++ b/vendor/crypto-bigint/src/uint/concat.rs
@@ -0,0 +1,70 @@
+use crate::{Concat, ConcatMixed, Limb, Uint};
+
+impl<T> Concat for T
+where
+    T: ConcatMixed<T>,
+{
+    type Output = Self::MixedOutput;
+}
+
+/// Concatenate the two values, with `lo` as least significant and `hi`
+/// as the most significant.
+#[inline]
+pub(crate) const fn concat_mixed<const L: usize, const H: usize, const O: usize>(
+    lo: &Uint<L>,
+    hi: &Uint<H>,
+) -> Uint<O> {
+    let top = L + H;
+    let top = if top < O { top } else { O };
+    let mut limbs = [Limb::ZERO; O];
+    let mut i = 0;
+
+    while i < top {
+        if i < L {
+            limbs[i] = lo.limbs[i];
+        } else {
+            limbs[i] = hi.limbs[i - L];
+        }
+        i += 1;
+    }
+
+    Uint { limbs }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::{ConcatMixed, U128, U192, U64};
+
+    #[test]
+    fn concat() {
+        let hi = U64::from_u64(0x0011223344556677);
+        let lo = U64::from_u64(0x8899aabbccddeeff);
+        assert_eq!(
+            hi.concat(&lo),
+            U128::from_be_hex("00112233445566778899aabbccddeeff")
+        );
+    }
+
+    #[test]
+    fn concat_mixed() {
+        let a = U64::from_u64(0x0011223344556677);
+        let b = U128::from_u128(0x8899aabbccddeeff_8899aabbccddeeff);
+        assert_eq!(
+            a.concat_mixed(&b),
+            U192::from_be_hex("00112233445566778899aabbccddeeff8899aabbccddeeff")
+        );
+        assert_eq!(
+            b.concat_mixed(&a),
+            U192::from_be_hex("8899aabbccddeeff8899aabbccddeeff0011223344556677")
+        );
+    }
+
+    #[test]
+    fn convert() {
+        let res: U128 = U64::ONE.mul_wide(&U64::ONE).into();
+        assert_eq!(res, U128::ONE);
+
+        let res: U128 = U64::ONE.square_wide().into();
+        assert_eq!(res, U128::ONE);
+    }
+}