feat: add BLS12-381

.gitignore

@@ -2,4 +2,4 @@
 Cargo.lock
 **/*.rs.bk
 .vscode
-**/*.html
+**/*.html

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "halo2curves"
-version = "0.3.1"
+version = "0.3.2"
 authors = [
   "Sean Bowe <ewillbefull@gmail.com>",
   "Jack Grigg <jack@z.cash>",
@@ -16,6 +16,7 @@ description = "Elliptic curve implementations and wrappers for halo2 library"
 criterion = { version = "0.3", features = ["html_reports"] }
 rand_xorshift = "0.3"
 ark-std = { version = "0.3", features = ["print-trace"] }
+pretty_assertions = "1.3.0"
 
 [dependencies]
 subtle = "2.4"

rust-toolchain

@@ -0,0 +1 @@
+nightly

src/arithmetic.rs

@@ -76,6 +76,13 @@ pub(crate) const fn adc(a: u64, b: u64, carry: bool) -> (u64, bool) {
     a.carrying_add(b, carry)
 }
 
+/// Compute a + b + carry, returning the result and the new carry as a u64.
+#[inline(always)]
+pub(crate) const fn adc_u64(a: u64, b: u64, carry: u64) -> (u64, u64) {
+    let ret = (a as u128) + (b as u128) + (carry as u128);
+    (ret as u64, (ret >> 64) as u64)
+}
+
 /// Compute a - b - borrow, returning the result and the new borrow.
 #[inline(always)]
 pub(crate) const fn sbb(a: u64, b: u64, borrow: bool) -> (u64, bool) {