Refactor Fp code to use const generics, and more (#379)

Co-authored-by: Weikeng Chen <w.k@berkeley.edu>
Co-authored-by: Marcin <marcin.gorny.94@protonmail.com>

ec/Cargo.toml

@@ -11,7 +11,7 @@ categories = ["cryptography"]
 include = ["Cargo.toml", "src", "README.md", "LICENSE-APACHE", "LICENSE-MIT"]
 license = "MIT/Apache-2.0"
 edition = "2021"
-rust-version = "1.56"
+rust-version = "1.57"
 
 [dependencies]
 ark-std = { version = "^0.3.0", default-features = false }

ec/src/models/bls12/mod.rs

@@ -4,8 +4,8 @@ use crate::{
 };
 use ark_ff::fields::{
     fp12_2over3over2::{Fp12, Fp12Parameters},
-    fp2::Fp2Parameters,
-    fp6_3over2::Fp6Parameters,
+    fp2::Fp2Config,
+    fp6_3over2::Fp6Config,
     BitIteratorBE, Field, Fp2, PrimeField, SquareRootField,
 };
 use core::marker::PhantomData;
@@ -34,8 +34,8 @@ pub trait Bls12Parameters: 'static {
     const TWIST_TYPE: TwistType;
 
     type Fp: PrimeField + SquareRootField + Into<<Self::Fp as PrimeField>::BigInt>;
-    type Fp2Params: Fp2Parameters<Fp = Self::Fp>;
-    type Fp6Params: Fp6Parameters<Fp2Params = Self::Fp2Params>;
+    type Fp2Params: Fp2Config<Fp = Self::Fp>;
+    type Fp6Params: Fp6Config<Fp2Params = Self::Fp2Params>;
     type Fp12Params: Fp12Parameters<Fp6Params = Self::Fp6Params>;
     type G1Parameters: SWModelParameters<BaseField = Self::Fp>;
     type G2Parameters: SWModelParameters<
@@ -68,12 +68,12 @@ impl<P: Bls12Parameters> Bls12<P> {
                 c2.mul_assign_by_fp(&p.y);
                 c1.mul_assign_by_fp(&p.x);
                 f.mul_by_014(&c0, &c1, &c2);
-            }
+            },
             TwistType::D => {
                 c0.mul_assign_by_fp(&p.y);
                 c1.mul_assign_by_fp(&p.x);
                 f.mul_by_034(&c0, &c1, &c2);
-            }
+            },
         }
     }
 

ec/src/models/bn/g2.rs

@@ -92,10 +92,10 @@ impl<P: BnParameters> From<G2Affine<P>> for G2Prepared<P> {
             match bit {
                 1 => {
                     ell_coeffs.push(addition_step::<P>(&mut r, &q));
-                }
+                },
                 -1 => {
                     ell_coeffs.push(addition_step::<P>(&mut r, &negq));
-                }
+                },
                 _ => continue,
             }
         }

ec/src/models/bn/mod.rs

@@ -4,8 +4,8 @@ use crate::{
 };
 use ark_ff::fields::{
     fp12_2over3over2::{Fp12, Fp12Parameters},
-    fp2::Fp2Parameters,
-    fp6_3over2::Fp6Parameters,
+    fp2::Fp2Config,
+    fp6_3over2::Fp6Config,
     Field, Fp2, PrimeField, SquareRootField,
 };
 use num_traits::One;
@@ -32,8 +32,8 @@ pub trait BnParameters: 'static {
     const TWIST_MUL_BY_Q_X: Fp2<Self::Fp2Params>;
     const TWIST_MUL_BY_Q_Y: Fp2<Self::Fp2Params>;
     type Fp: PrimeField + SquareRootField + Into<<Self::Fp as PrimeField>::BigInt>;
-    type Fp2Params: Fp2Parameters<Fp = Self::Fp>;
-    type Fp6Params: Fp6Parameters<Fp2Params = Self::Fp2Params>;
+    type Fp2Params: Fp2Config<Fp = Self::Fp>;
+    type Fp6Params: Fp6Config<Fp2Params = Self::Fp2Params>;
     type Fp12Params: Fp12Parameters<Fp6Params = Self::Fp6Params>;
     type G1Parameters: SWModelParameters<BaseField = Self::Fp>;
     type G2Parameters: SWModelParameters<
@@ -66,12 +66,12 @@ impl<P: BnParameters> Bn<P> {
                 c2.mul_assign_by_fp(&p.y);
                 c1.mul_assign_by_fp(&p.x);
                 f.mul_by_014(&c0, &c1, &c2);
-            }
+            },
             TwistType::D => {
                 c0.mul_assign_by_fp(&p.y);
                 c1.mul_assign_by_fp(&p.x);
                 f.mul_by_034(&c0, &c1, &c2);
-            }
+            },
         }
     }
 
@@ -124,12 +124,12 @@ impl<P: BnParameters> PairingEngine for Bn<P> {
                     for &mut (p, ref mut coeffs) in &mut pairs {
                         Self::ell(&mut f, coeffs.next().unwrap(), &p.0);
                     }
-                }
+                },
                 -1 => {
                     for &mut (p, ref mut coeffs) in &mut pairs {
                         Self::ell(&mut f, coeffs.next().unwrap(), &p.0);
                     }
-                }
+                },
                 _ => continue,
             }
         }

ec/src/models/bw6/g2.rs

@@ -112,10 +112,10 @@ impl<P: BW6Parameters> From<G2Affine<P>> for G2Prepared<P> {
             match bit {
                 1 => {
                     ell_coeffs_2.push(addition_step::<P>(&mut r, &q));
-                }
+                },
                 -1 => {
                     ell_coeffs_2.push(addition_step::<P>(&mut r, &negq));
-                }
+                },
                 _ => continue,
             }
         }

ec/src/models/bw6/mod.rs

@@ -3,8 +3,8 @@ use crate::{
     PairingEngine,
 };
 use ark_ff::fields::{
-    fp3::Fp3Parameters,
-    fp6_2over3::{Fp6, Fp6Parameters},
+    fp3::Fp3Config,
+    fp6_2over3::{Fp6, Fp6Config},
     BitIteratorBE, Field, PrimeField, SquareRootField,
 };
 use num_traits::One;
@@ -25,8 +25,8 @@ pub trait BW6Parameters: 'static + Eq + PartialEq {
     const ATE_LOOP_COUNT_2_IS_NEGATIVE: bool;
     const TWIST_TYPE: TwistType;
     type Fp: PrimeField + SquareRootField + Into<<Self::Fp as PrimeField>::BigInt>;
-    type Fp3Params: Fp3Parameters<Fp = Self::Fp>;
-    type Fp6Params: Fp6Parameters<Fp3Params = Self::Fp3Params>;
+    type Fp3Params: Fp3Config<Fp = Self::Fp>;
+    type Fp6Params: Fp6Config<Fp3Params = Self::Fp3Params>;
     type G1Parameters: SWModelParameters<BaseField = Self::Fp>;
     type G2Parameters: SWModelParameters<
         BaseField = Self::Fp,
@@ -58,12 +58,12 @@ impl<P: BW6Parameters> BW6<P> {
                 c2 *= &p.y;
                 c1 *= &p.x;
                 f.mul_by_014(&c0, &c1, &c2);
-            }
+            },
             TwistType::D => {
                 c0 *= &p.y;
                 c1 *= &p.x;
                 f.mul_by_034(&c0, &c1, &c2);
-            }
+            },
         }
     }
 
@@ -274,12 +274,12 @@ impl<P: BW6Parameters> PairingEngine for BW6<P> {
                     for &mut (p, ref mut coeffs) in &mut pairs_2 {
                         Self::ell(&mut f_2, coeffs.next().unwrap(), &p.0);
                     }
-                }
+                },
                 -1 => {
                     for &mut (p, ref mut coeffs) in &mut pairs_2 {
                         Self::ell(&mut f_2, coeffs.next().unwrap(), &p.0);
                     }
-                }
+                },
                 _ => continue,
             }
         }

ec/src/models/mnt4/mod.rs

@@ -3,8 +3,8 @@ use crate::{
     PairingEngine,
 };
 use ark_ff::{
-    fp2::{Fp2, Fp2Parameters},
-    fp4::{Fp4, Fp4Parameters},
+    fp2::{Fp2, Fp2Config},
+    fp4::{Fp4, Fp4Config},
     BitIteratorBE, Field, PrimeField, SquareRootField,
 };
 use num_traits::{One, Zero};
@@ -32,8 +32,8 @@ pub trait MNT4Parameters: 'static {
     const FINAL_EXPONENT_LAST_CHUNK_ABS_OF_W0: <Self::Fp as PrimeField>::BigInt;
     type Fp: PrimeField + SquareRootField + Into<<Self::Fp as PrimeField>::BigInt>;
     type Fr: PrimeField + SquareRootField + Into<<Self::Fr as PrimeField>::BigInt>;
-    type Fp2Params: Fp2Parameters<Fp = Self::Fp>;
-    type Fp4Params: Fp4Parameters<Fp2Params = Self::Fp2Params>;
+    type Fp2Params: Fp2Config<Fp = Self::Fp>;
+    type Fp4Params: Fp4Config<Fp2Params = Self::Fp2Params>;
     type G1Parameters: SWModelParameters<BaseField = Self::Fp, ScalarField = Self::Fr>;
     type G2Parameters: SWModelParameters<
         BaseField = Fp2<Self::Fp2Params>,

ec/src/models/mnt6/mod.rs

@@ -3,8 +3,8 @@ use crate::{
     PairingEngine,
 };
 use ark_ff::{
-    fp3::{Fp3, Fp3Parameters},
-    fp6_2over3::{Fp6, Fp6Parameters},
+    fp3::{Fp3, Fp3Config},
+    fp6_2over3::{Fp6, Fp6Config},
     BitIteratorBE, Field, PrimeField, SquareRootField,
 };
 use num_traits::{One, Zero};
@@ -32,8 +32,8 @@ pub trait MNT6Parameters: 'static {
     const FINAL_EXPONENT_LAST_CHUNK_ABS_OF_W0: <Self::Fp as PrimeField>::BigInt;
     type Fp: PrimeField + SquareRootField + Into<<Self::Fp as PrimeField>::BigInt>;
     type Fr: PrimeField + SquareRootField + Into<<Self::Fr as PrimeField>::BigInt>;
-    type Fp3Params: Fp3Parameters<Fp = Self::Fp>;
-    type Fp6Params: Fp6Parameters<Fp3Params = Self::Fp3Params>;
+    type Fp3Params: Fp3Config<Fp = Self::Fp>;
+    type Fp6Params: Fp6Config<Fp3Params = Self::Fp3Params>;
     type G1Parameters: SWModelParameters<BaseField = Self::Fp, ScalarField = Self::Fr>;
     type G2Parameters: SWModelParameters<
         BaseField = Fp3<Self::Fp3Params>,

ec/src/models/short_weierstrass_jacobian.rs

@@ -688,7 +688,7 @@ impl<'a, P: Parameters> SubAssign<&'a Self> for GroupProjective<P> {
 
 impl<P: Parameters> MulAssign<P::ScalarField> for GroupProjective<P> {
     fn mul_assign(&mut self, other: P::ScalarField) {
-        *self = self.mul(other.into_repr())
+        *self = self.mul(other.into_bigint())
     }
 }
 

ec/src/models/twisted_edwards_extended.rs

@@ -200,7 +200,7 @@ impl<'a, P: Parameters> SubAssign<&'a Self> for GroupAffine<P> {
 
 impl<P: Parameters> MulAssign<P::ScalarField> for GroupAffine<P> {
     fn mul_assign(&mut self, other: P::ScalarField) {
-        *self = self.mul(other.into_repr()).into()
+        *self = self.mul(other.into_bigint()).into()
     }
 }
 
@@ -583,7 +583,7 @@ impl<'a, P: Parameters> SubAssign<&'a Self> for GroupProjective<P> {
 
 impl<P: Parameters> MulAssign<P::ScalarField> for GroupProjective<P> {
     fn mul_assign(&mut self, other: P::ScalarField) {
-        *self = self.mul(other.into_repr())
+        *self = self.mul(other.into_bigint())
     }
 }
 

ec/src/msm/fixed_base.rs

@@ -1,5 +1,5 @@
 use crate::{AffineCurve, ProjectiveCurve};
-use ark_ff::{BigInteger, FpParameters, PrimeField};
+use ark_ff::{BigInteger, PrimeField};
 use ark_std::{cfg_iter, cfg_iter_mut, vec::Vec};
 
 #[cfg(feature = "parallel")]
@@ -63,8 +63,8 @@ impl FixedBase {
         multiples_of_g: &[Vec<T::Affine>],
         scalar: &T::ScalarField,
     ) -> T {
-        let modulus_size = <T::ScalarField as PrimeField>::Params::MODULUS_BITS as usize;
-        let scalar_val = scalar.into_repr().to_bits_le();
+        let modulus_size = T::ScalarField::MODULUS_BIT_SIZE as usize;
+        let scalar_val = scalar.into_bigint().to_bits_le();
 
         let mut res = multiples_of_g[0][0].into_projective();
         for outer in 0..outerc {

ec/src/msm/variable_base/mod.rs

@@ -47,8 +47,8 @@ impl VariableBase {
             super::ln_without_floats(size) + 2
         };
 
-        let num_bits = <G::ScalarField as PrimeField>::Params::MODULUS_BITS as usize;
-        let fr_one = G::ScalarField::one().into_repr();
+        let num_bits = G::ScalarField::MODULUS_BIT_SIZE as usize;
+        let fr_one = G::ScalarField::one().into_bigint();
 
         let zero = G::Projective::zero();
         let window_starts: Vec<_> = (0..num_bits).step_by(c).collect();

ec/src/wnaf.rs

@@ -52,7 +52,7 @@ impl WnafContext {
         if 1 << (self.window_size - 1) > base_table.len() {
             return None;
         }
-        let scalar_wnaf = scalar.into_repr().find_wnaf(self.window_size).unwrap();
+        let scalar_wnaf = scalar.into_bigint().find_wnaf(self.window_size).unwrap();
 
         let mut result = G::zero();
 

ff-asm/Cargo.toml

@@ -11,7 +11,7 @@ categories = ["cryptography"]
 include = ["Cargo.toml", "src", "README.md", "LICENSE-APACHE", "LICENSE-MIT"]
 license = "MIT/Apache-2.0"
 edition = "2021"
-rust-version = "1.56"
+rust-version = "1.57"
 
 [dependencies]
 quote = "1.0.0"

ff-asm/src/lib.rs

@@ -298,9 +298,9 @@ fn generate_impl(num_limbs: usize, is_mul: bool) -> String {
     if is_mul {
         ctx.add_declaration("b", "r", "b");
     }
-    ctx.add_declaration("modulus", "r", "&P::MODULUS.0");
+    ctx.add_declaration("modulus", "r", "&Self::MODULUS.0");
     ctx.add_declaration("0", "i", "0u64");
-    ctx.add_declaration("mod_prime", "i", "P::INV");
+    ctx.add_declaration("mod_prime", "i", "Self::INV");
 
     if num_limbs > MAX_REGS {
         ctx.add_buffer(2 * num_limbs);

ff/Cargo.toml

@@ -12,7 +12,7 @@ include = ["Cargo.toml", "build.rs", "src", "README.md", "LICENSE-APACHE", "LICE
 license = "MIT/Apache-2.0"
 edition = "2021"
 build = "build.rs"
-rust-version = "1.56"
+rust-version = "1.57"
 
 [dependencies]
 ark-ff-asm = { version = "^0.3.0", path = "../ff-asm" }

ff/README.md

@@ -7,33 +7,33 @@
 </p>
 
 This crate defines Finite Field traits and useful abstraction models that follow these traits.
-Implementations of finite fields with concrete parameters can be found in [`arkworks-rs/curves`](https://github.com/arkworks-rs/curves/README.md) under `arkworks-rs/curves/<your favourite curve>/src/fields/`, which are used for some of the popular curves, such as a specific [`Fq`](https://github.com/arkworks-rs/curves/blob/master/bls12_381/src/fields/fq.rs) used in BLS-381.
+Implementations of concrete finite fields for some popular elliptic curves can be found in [`arkworks-rs/curves`](https://github.com/arkworks-rs/curves/README.md) under `arkworks-rs/curves/<your favourite curve>/src/fields/`.
 
 This crate contains two types of traits:
 
 - `Field` traits: These define interfaces for manipulating field elements, such as addition, multiplication, inverses, square roots, and more.
-- Field Parameters: holds the parameters defining the field in question. For extension fields, it also provides additional functionality required for the field, such as operations involving a (cubic or quadratic) non-residue used for constructing the field (`NONRESIDUE`).
+- Field `Config`s: specifies the parameters defining the field in question. For extension fields, it also provides additional functionality required for the field, such as operations involving a (cubic or quadratic) non-residue used for constructing the field (`NONRESIDUE`).
 
 The available field traits are:
 
-- [`Field`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/mod.rs#L66) - Interface for the most generic finte field
-- [`FftField`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/mod.rs#L275) - Exposes methods that allow for performing efficient FFTs on this field's elements
-- [`PrimeField`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/mod.rs#L347) - Field with `p` (`p` prime) elements, later referred to as `Fp`.
+- [`Field`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/mod.rs#L66) - Interface for a generic finite field.
+- [`FftField`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/mod.rs#L275) - Exposes methods that allow for performing efficient FFTs on field elements.
+- [`PrimeField`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/mod.rs#L347) - Field with a prime `p` number of elements, also referred to as `Fp`.
 - [`SquareRootField`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/mod.rs#L431) - Interface for fields that support square-root operations
 
 The models implemented are:
 
 - [`Quadratic Extension`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/models/quadratic_extension.rs)
-- [`QuadExtField`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/models/quadratic_extension.rs#L140) - Struct representing a quadratic extension field, in this case holding two elements
-- [`QuadExtParameters`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/models/quadratic_extension.rs#L27) - Trait defining the necessary parameters needed to instantiate a Quadratic Extension Field
+    - [`QuadExtField`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/models/quadratic_extension.rs#L140) - Struct representing a quadratic extension field, in this case holding two base field elements
+    - [`QuadExtConfig`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/models/quadratic_extension.rs#L27) - Trait defining the necessary parameters needed to instantiate a Quadratic Extension Field
 - [`Cubic Extension`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/models/cubic_extension.rs)
-- [`CubicExtField`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/models/cubic_extension.rs#L72) - Struct representing a cubic extension field, holds three elements
-- [`CubicExtParameters`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/models/cubic_extension.rs#L27) - Trait defining the necessary parameters needed to instantiate a Cubic Extension Field
+    - [`CubicExtField`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/models/cubic_extension.rs#L72) - Struct representing a cubic extension field, holds three base field elements
+    - [`CubicExtConfig`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/models/cubic_extension.rs#L27) - Trait defining the necessary parameters needed to instantiate a Cubic Extension Field
 
 The above two models serve as abstractions for constructing the extension fields `Fp^m` directly (i.e. `m` equal 2 or 3) or for creating extension towers to arrive at higher `m`. The latter is done by applying the extensions iteratively, e.g. cubic extension over a quadratic extension field.
 
 - [`Fp2`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/models/fp2.rs#L103) - Quadratic extension directly on the prime field, i.e. `BaseField == BasePrimeField`
 - [`Fp3`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/models/fp3.rs#L54) - Cubic extension directly on the prime field, i.e. `BaseField == BasePrimeField`
 - [`Fp6_2over3`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/models/fp6_2over3.rs#L48) - Extension tower: quadratic extension on a cubic extension field, i.e. `BaseField = Fp3`, but `BasePrimeField = Fp`.
 - [`Fp6_3over2`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/models/fp6_3over2.rs#L49) - Extension tower, similar to the above except that the towering order is reversed: it's a cubic extension on a quadratic extension field, i.e. `BaseField = Fp2`, but `BasePrimeField = Fp`. Only this latter one is exported by default as `Fp6`.
-- [`Fp12_2over3over2`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/models/fp12_2over3over2.rs#L83) - Extension tower: quadratic extension of the `Fp6_3over2`, i.e. `BaseField = Fp6`.
+- [`Fp12_2over3over2`](https://github.com/arkworks-rs/algebra/blob/master/ff/src/fields/models/fp12_2over3over2.rs#L83) - Extension tower: quadratic extension of `Fp6_3over2`, i.e. `BaseField = Fp6`.