Add parallel miller loop (#279)

* parallelize miller loops * completed bls12 miller_loop parallelization * restores logic for when parallel feature is off * cargo cleanups * cleanups * cargo fmt * adds changelog entry * fixed changelog * moved to cfg_iter, cleanups * formatting * minor fixes * minor fixes * Bump the version of super-linter (#283) * Fix the panicking `subgroup_fft_in_place` benchmark for MNT6-753's Fr (#284) * fix the bench test failure * update the CHANGELOG * lint * lint * Implement `Into<BigUint>` and `From<BigUint>` for `BigInteger` and `PrimeField` (#280) * add into and from BigUint for BigInteger * update changelog, cargo fmt * linter * update changelog, cargo fmt * change the algorithm; implement for PrimeField as well * less confusing variable name * for BigInteger, do TryFrom instead of From; for PrimeField, do a mod * handle the error of TryFrom; add a test for Fr into/from BigUint * fmt, clippy * Add sparse scalar mul and sub (#259) * Add/Sub impl for Sparse and Dense polys, Mul<F> for SparsePolynomial * Add test and update changelog * Fmt * Update CHANGELOG.md * add add_assign and sub_assign * fmt Co-authored-by: Weikeng Chen <[email protected]> * parallelize miller loops * completed bls12 miller_loop parallelization * restores logic for when parallel feature is off * cargo cleanups * cleanups * cargo fmt * adds changelog entry * fixed changelog * moved to cfg_iter, cleanups * formatting * minor fixes * minor fixes Co-authored-by: Weikeng Chen <[email protected]> Co-authored-by: Ryan Lehmkuhl <[email protected]>
arkworks-rs · May 28, 2021 · ff550af · ff550af
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commit ff550af
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diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -14,10 +14,13 @@
 - [\#263](https://github.com/arkworks-rs/algebra/pull/263) (ark-ff) Add `From<iXXX>` implementations to fields.
 - [\#265](https://github.com/arkworks-rs/algebra/pull/265) (ark-serialize) Add hashing as an extension trait of `CanonicalSerialize`.
 - [\#280](https://github.com/arkworks-rs/algebra/pull/280) (ark-ff) Add `Into<BigUint>` and `From<BigUint>` implementations to `BigInteger` and `PrimeField`.
+- [\#279](https://github.com/arkworks-rs/algebra/pull/279) (ark-ec) Parallelize miller loop operations for BLS12.
 
 ### Improvements
+- [\#279](https://github.com/arkworks-rs/algebra/pull/279) (ark-ec) Parallelize miller loop operations for BLS12.
 
 ### Bug fixes
+- [\#252](https://github.com/arkworks-rs/algebra/pull/252) (ark-ff) Fix prime field sampling when `REPR_SHIFT_BITS` is 64.
 
 - [\#252](https://github.com/arkworks-rs/algebra/pull/252) (ark-ff) Fix prime field sampling when `REPR_SHIFT_BITS` is 64.
 - [\#284](https://github.com/arkworks-rs/algebra/pull/284) (ark-poly-benches) Fix the panic `subgroup_fft_in_place` benchmark for MNT6-753's Fr.

diff --git a/ec/src/models/bls12/mod.rs b/ec/src/models/bls12/mod.rs
@@ -8,11 +8,20 @@ use ark_ff::fields::{
     fp6_3over2::Fp6Parameters,
     BitIteratorBE, Field, Fp2, PrimeField, SquareRootField,
 };
+use core::marker::PhantomData;
 use num_traits::{One, Zero};
 
-use core::marker::PhantomData;
+#[cfg(feature = "parallel")]
+use ark_ff::{Fp12ParamsWrapper, Fp2ParamsWrapper, QuadExtField};
+#[cfg(feature = "parallel")]
+use ark_std::cfg_iter;
+#[cfg(feature = "parallel")]
+use core::slice::Iter;
+#[cfg(feature = "parallel")]
+use rayon::iter::{IndexedParallelIterator, IntoParallelRefIterator, ParallelIterator};
 
-/// A particular BLS12 group can have G2 being either a multiplicative or a divisive twist.
+/// A particular BLS12 group can have G2 being either a multiplicative or a
+/// divisive twist.
 pub enum TwistType {
     M,
     D,
@@ -91,6 +100,7 @@ impl<P: Bls12Parameters> PairingEngine for Bls12<P> {
     type Fqe = Fp2<P::Fp2Params>;
     type Fqk = Fp12<P::Fp12Params>;
 
+    #[cfg(not(feature = "parallel"))]
     fn miller_loop<'a, I>(i: I) -> Self::Fqk
     where
         I: IntoIterator<Item = &'a (Self::G1Prepared, Self::G2Prepared)>,
@@ -101,27 +111,79 @@ impl<P: Bls12Parameters> PairingEngine for Bls12<P> {
                 pairs.push((p, q.ell_coeffs.iter()));
             }
         }
-
         let mut f = Self::Fqk::one();
-
         for i in BitIteratorBE::new(P::X).skip(1) {
             f.square_in_place();
-
             for (p, ref mut coeffs) in &mut pairs {
                 Self::ell(&mut f, coeffs.next().unwrap(), &p.0);
             }
-
             if i {
                 for &mut (p, ref mut coeffs) in &mut pairs {
                     Self::ell(&mut f, coeffs.next().unwrap(), &p.0);
                 }
             }
         }
-
         if P::X_IS_NEGATIVE {
             f.conjugate();
         }
+        f
+    }
 
+    #[cfg(feature = "parallel")]
+    fn miller_loop<'a, I>(i: I) -> Self::Fqk
+    where
+        I: IntoIterator<Item = &'a (Self::G1Prepared, Self::G2Prepared)>,
+    {
+        let mut pairs = vec![];
+        for (p, q) in i {
+            if !p.is_zero() && !q.is_zero() {
+                pairs.push((p, q.ell_coeffs.iter()));
+            }
+        }
+
+        let mut f_vec = vec![];
+        for _ in 0..pairs.len() {
+            f_vec.push(Self::Fqk::one());
+        }
+
+        let a = |p: &&G1Prepared<P>,
+                 coeffs: &Iter<
+            '_,
+            (
+                QuadExtField<Fp2ParamsWrapper<<P as Bls12Parameters>::Fp2Params>>,
+                QuadExtField<Fp2ParamsWrapper<<P as Bls12Parameters>::Fp2Params>>,
+                QuadExtField<Fp2ParamsWrapper<<P as Bls12Parameters>::Fp2Params>>,
+            ),
+        >,
+                 mut f: QuadExtField<Fp12ParamsWrapper<<P as Bls12Parameters>::Fp12Params>>|
+         -> QuadExtField<Fp12ParamsWrapper<<P as Bls12Parameters>::Fp12Params>> {
+            let coeffs = coeffs.as_slice();
+            let mut j = 0;
+            for i in BitIteratorBE::new(P::X).skip(1) {
+                f.square_in_place();
+                Self::ell(&mut f, &coeffs[j], &p.0);
+                j += 1;
+                if i {
+                    Self::ell(&mut f, &coeffs[j], &p.0);
+                    j += 1;
+                }
+            }
+            f
+        };
+
+        let mut products = vec![];
+        cfg_iter!(pairs)
+            .zip(f_vec)
+            .map(|(p, f)| a(&p.0, &p.1, f))
+            .collect_into_vec(&mut products);
+
+        let mut f = Self::Fqk::one();
+        for ff in products {
+            f *= ff;
+        }
+        if P::X_IS_NEGATIVE {
+            f.conjugate();
+        }
         f
     }