Add FieldVar::inner_product and Sum bounds on FieldVar

Cargo.toml

@@ -21,6 +21,7 @@ ark-relations = { version = "0.5.0", default-features = false }
 
 educe = "0.6.0"
 tracing = { version = "^0.1.0", default-features = false, features = ["attributes"] }
+itertools = { version = "0.14.0", default-features = false, features = [ "use_alloc" ] }
 num-bigint = { version = "0.4", default-features = false }
 num-traits = { version = "0.2", default-features = false }
 num-integer = { version = "0.1.44", default-features = false }
@@ -45,7 +46,7 @@ tracing-subscriber = { version = "0.3", default-features = true }
 
 [features]
 default = ["std"]
-std = ["ark-ff/std", "ark-relations/std", "ark-std/std", "num-bigint/std"]
+std = ["ark-ff/std", "ark-relations/std", "ark-std/std", "num-bigint/std", "itertools/use_std" ]
 parallel = ["std", "ark-ff/parallel", "ark-std/parallel"]
 
 [[bench]]

src/fields/cubic_extension.rs

@@ -9,7 +9,7 @@ use ark_ff::{
     CubicExtConfig, Zero,
 };
 use ark_relations::gr1cs::{ConstraintSystemRef, Namespace, SynthesisError};
-use core::{borrow::Borrow, marker::PhantomData};
+use core::{borrow::Borrow, iter::Sum, marker::PhantomData};
 use educe::Educe;
 
 /// This struct is the `R1CS` equivalent of the cubic extension field type
@@ -576,3 +576,41 @@ where
         Ok(Self::new(c0, c1, c2))
     }
 }
+
+impl<BF, P> Sum<Self> for CubicExtVar<BF, P>
+where
+    BF: FieldVar<P::BaseField, P::BasePrimeField>,
+    for<'a> &'a BF: FieldOpsBounds<'a, P::BaseField, BF>,
+    P: CubicExtVarConfig<BF>,
+{
+    #[inline]
+    #[tracing::instrument(target = "gr1cs", skip(iter))]
+    fn sum<I: Iterator<Item = Self>>(iter: I) -> Self {
+        let (c0s, c1s, c2s): (Vec<_>, Vec<_>, Vec<_>) =
+            itertools::multiunzip(iter.map(|x| (x.c0, x.c1, x.c2)));
+        let c0 = c0s.into_iter().sum();
+        let c1 = c1s.into_iter().sum();
+        let c2 = c2s.into_iter().sum();
+
+        Self::new(c0, c1, c2)
+    }
+}
+
+impl<'a, BF, P> Sum<&'a Self> for CubicExtVar<BF, P>
+where
+    BF: FieldVar<P::BaseField, P::BasePrimeField>,
+    for<'b> &'b BF: FieldOpsBounds<'b, P::BaseField, BF>,
+    P: CubicExtVarConfig<BF>,
+{
+    #[inline]
+    #[tracing::instrument(target = "gr1cs", skip(iter))]
+    fn sum<I: Iterator<Item = &'a Self>>(iter: I) -> Self {
+        let (c0s, c1s, c2s): (Vec<_>, Vec<_>, Vec<_>) =
+            itertools::multiunzip(iter.map(|x| (&x.c0, &x.c1, &x.c2)));
+        let c0 = c0s.into_iter().sum();
+        let c1 = c1s.into_iter().sum();
+        let c2 = c2s.into_iter().sum();
+
+        Self::new(c0, c1, c2)
+    }
+}

src/fields/emulated_fp/field_var.rs

@@ -1,3 +1,5 @@
+use core::iter::Sum;
+
 use super::{params::OptimizationType, AllocatedEmulatedFpVar, MulResultVar};
 use crate::{
     boolean::Boolean,
@@ -471,3 +473,17 @@ impl<TargetF: PrimeField, BaseF: PrimeField> EmulatedFpVar<TargetF, BaseF> {
         }
     }
 }
+
+impl<TargetF: PrimeField, BaseF: PrimeField> Sum<Self> for EmulatedFpVar<TargetF, BaseF> {
+    #[tracing::instrument(target = "gr1cs", skip(iter))]
+    fn sum<I: Iterator<Item = Self>>(iter: I) -> Self {
+        iter.fold(Self::zero(), |acc, x| acc + x)
+    }
+}
+
+impl<'a, TargetF: PrimeField, BaseF: PrimeField> Sum<&'a Self> for EmulatedFpVar<TargetF, BaseF> {
+    #[tracing::instrument(target = "gr1cs", skip(iter))]
+    fn sum<I: Iterator<Item = &'a Self>>(iter: I) -> Self {
+        iter.fold(Self::zero(), |acc, x| acc + x)
+    }
+}