Refactor FRI implementation

starkware-libs · Oct 14, 2024 · 1eaef30 · 1eaef30
1 parent b51e6fd
commit 1eaef30
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Showing 10 changed files with 324 additions and 395 deletions.
diff --git a/stwo_cairo_verifier/src/channel.cairo b/stwo_cairo_verifier/src/channel.cairo
@@ -129,13 +129,12 @@ pub impl ChannelImpl of ChannelTrait {
     fn draw_random_bytes(ref self: Channel) -> Array<u8> {
         let mut cur: u256 = self.draw_felt252().into();
         let mut bytes = array![];
-        let mut i: usize = 0;
-        while i < 31 {
-            let (q, r) = DivRem::div_rem(cur, 256);
-            bytes.append(r.try_into().unwrap());
-            cur = q;
-            i += 1;
-        };
+        for _ in 0_usize
+            ..31 {
+                let (q, r) = DivRem::div_rem(cur, 256);
+                bytes.append(r.try_into().unwrap());
+                cur = q;
+            };
         bytes
     }
 }
@@ -224,9 +223,7 @@ mod tests {
         let initial_digest = 0;
         let mut channel = ChannelTrait::new(initial_digest);
 
-        let mut n: usize = 10;
-        while n > 0 {
-            n -= 1;
+        for _ in 0_usize..10 {
             channel.draw_felt();
         };
 

diff --git a/stwo_cairo_verifier/src/circle.cairo b/stwo_cairo_verifier/src/circle.cairo
@@ -156,7 +156,7 @@ pub impl CosetImpl of CosetTrait {
     }
 
     /// Creates a coset of the form `G_4n + <G_n>`.
-    /// 
+    ///
     /// For example, for `n=8`, we get the point indices `[1,5,9,13,17,21,25,29]`.
     /// Its conjugate will be `[3,7,11,15,19,23,27,31]`.
     fn half_odds(log_size: u32) -> Coset {
@@ -240,20 +240,22 @@ mod tests {
     use stwo_cairo_verifier::fields::m31::m31;
     use stwo_cairo_verifier::fields::qm31::{QM31One, qm31};
     use stwo_cairo_verifier::utils::pow;
-    use super::{M31_CIRCLE_GEN, CirclePointQM31Impl, QM31_CIRCLE_GEN, M31_CIRCLE_ORDER, CirclePoint, CirclePointM31Impl, CirclePointIndexImpl, Coset, CosetImpl, QM31_CIRCLE_ORDER};
+    use super::{
+        M31_CIRCLE_GEN, CirclePointQM31Impl, QM31_CIRCLE_GEN, M31_CIRCLE_ORDER, CirclePoint,
+        CirclePointM31Impl, CirclePointIndexImpl, Coset, CosetImpl, QM31_CIRCLE_ORDER
+    };
 
     #[test]
     fn test_add_1() {
-        let i = CirclePoint { x: m31(0), y: m31(1) };
-        let result = i + i;
-
-        assert_eq!(result, CirclePoint { x: -m31(1), y: m31(0) });
+        let g4 = CirclePoint { x: m31(0), y: m31(1) };
+        assert_eq!(g4 + g4, CirclePoint { x: -m31(1), y: m31(0) });
     }
 
     #[test]
     fn test_add_2() {
         let point_1 = CirclePoint { x: m31(750649172), y: m31(1991648574) };
         let point_2 = CirclePoint { x: m31(1737427771), y: m31(309481134) };
+
         let result = point_1 + point_2;
 
         assert_eq!(result, CirclePoint { x: m31(1476625263), y: m31(1040927458) });
@@ -270,6 +272,7 @@ mod tests {
     fn test_zero_2() {
         let point_1 = CirclePoint { x: m31(750649172), y: m31(1991648574) };
         let point_2 = CirclePointM31Impl::zero();
+
         let result = point_1 + point_2;
 
         assert_eq!(result, point_1.clone());
@@ -278,6 +281,7 @@ mod tests {
     #[test]
     fn test_mul_1() {
         let point_1 = CirclePoint { x: m31(750649172), y: m31(1991648574) };
+
         let result = point_1.mul(5);
 
         assert_eq!(result, point_1 + point_1 + point_1 + point_1 + point_1);
@@ -286,6 +290,7 @@ mod tests {
     #[test]
     fn test_mul_2() {
         let point_1 = CirclePoint { x: m31(750649172), y: m31(1991648574) };
+
         let result = point_1.mul(8);
 
         assert_eq!(
@@ -296,6 +301,7 @@ mod tests {
     #[test]
     fn test_mul_3() {
         let point_1 = CirclePoint { x: m31(750649172), y: m31(1991648574) };
+
         let result = point_1.mul(418776494);
 
         assert_eq!(result, CirclePoint { x: m31(1987283985), y: m31(1500510905) });
@@ -304,6 +310,7 @@ mod tests {
     #[test]
     fn test_generator_order() {
         let half_order = M31_CIRCLE_ORDER / 2;
+
         let mut result = M31_CIRCLE_GEN.mul(half_order.into());
 
         // Assert `M31_CIRCLE_GEN^{2^30}` equals `-1`.
@@ -319,7 +326,12 @@ mod tests {
 
     #[test]
     fn test_coset_index_at() {
-        let coset = Coset { initial_index: CirclePointIndexImpl::new(16777216), log_size: 5, step_size: CirclePointIndexImpl::new(67108864) };
+        let coset = Coset {
+            initial_index: CirclePointIndexImpl::new(16777216),
+            log_size: 5,
+            step_size: CirclePointIndexImpl::new(67108864)
+        };
+
         let result = coset.index_at(8);
 
         assert_eq!(result, CirclePointIndexImpl::new(553648128));
@@ -329,36 +341,68 @@ mod tests {
     fn test_coset_constructor() {
         let result = CosetImpl::new(CirclePointIndexImpl::new(16777216), 5);
 
-        assert_eq!(result, Coset { initial_index: CirclePointIndexImpl::new(16777216), log_size: 5, step_size: CirclePointIndexImpl::new(67108864) });
+        assert_eq!(
+            result,
+            Coset {
+                initial_index: CirclePointIndexImpl::new(16777216),
+                log_size: 5,
+                step_size: CirclePointIndexImpl::new(67108864)
+            }
+        );
     }
 
     #[test]
     fn test_coset_double() {
-        let coset = Coset { initial_index: CirclePointIndexImpl::new(16777216), step_size: CirclePointIndexImpl::new(67108864), log_size: 5 };
+        let coset = Coset {
+            initial_index: CirclePointIndexImpl::new(16777216),
+            step_size: CirclePointIndexImpl::new(67108864),
+            log_size: 5
+        };
+
         let result = coset.double();
 
-        assert_eq!(result, Coset { initial_index: CirclePointIndexImpl::new(33554432), step_size: CirclePointIndexImpl::new(134217728), log_size: 4 });
+        assert_eq!(
+            result,
+            Coset {
+                initial_index: CirclePointIndexImpl::new(33554432),
+                step_size: CirclePointIndexImpl::new(134217728),
+                log_size: 4
+            }
+        );
     }
 
     #[test]
     fn test_coset_at() {
-        let coset = Coset { initial_index: CirclePointIndexImpl::new(16777216), step_size: CirclePointIndexImpl::new(67108864), log_size: 5 };
+        let coset = Coset {
+            initial_index: CirclePointIndexImpl::new(16777216),
+            step_size: CirclePointIndexImpl::new(67108864),
+            log_size: 5
+        };
+
         let result = coset.at(17);
 
         assert_eq!(result, CirclePoint { x: m31(7144319), y: m31(1742797653) });
     }
 
     #[test]
     fn test_coset_size() {
-        let coset = Coset { initial_index: CirclePointIndexImpl::new(16777216), step_size: CirclePointIndexImpl::new(67108864), log_size: 5 };
+        let coset = Coset {
+            initial_index: CirclePointIndexImpl::new(16777216),
+            step_size: CirclePointIndexImpl::new(67108864),
+            log_size: 5
+        };
+
         let result = coset.size();
 
         assert_eq!(result, 32);
     }
 
     #[test]
     fn test_qm31_circle_gen() {
-        assert_eq!(QM31_CIRCLE_GEN.mul(QM31_CIRCLE_ORDER / 2), CirclePoint { x: -qm31(1, 0, 0, 0), y: qm31(0, 0, 0, 0) });
+        assert_eq!(
+            QM31_CIRCLE_GEN.mul(QM31_CIRCLE_ORDER / 2),
+            CirclePoint { x: -qm31(1, 0, 0, 0), y: qm31(0, 0, 0, 0) }
+        );
     }
 }
 
diff --git a/stwo_cairo_verifier/src/fields/qm31.cairo b/stwo_cairo_verifier/src/fields/qm31.cairo
@@ -22,19 +22,11 @@ pub impl QM31Impl of QM31Trait {
         QM31 { a: CM31 { a: a, b: b }, b: CM31 { a: c, b: d } }
     }
 
-    fn from_u32(arr: [u32; 4]) -> QM31 {
-        let [a, b, c, d] = arr;
-        let a_mod_p = M31Impl::reduce_u32(a);
-        let b_mod_p = M31Impl::reduce_u32(b);
-        let c_mod_p = M31Impl::reduce_u32(c);
-        let d_mod_p = M31Impl::reduce_u32(d);
-
-        QM31 { a: CM31 { a: a_mod_p, b: b_mod_p }, b: CM31 { a: c_mod_p, b: d_mod_p } }
-    }
     #[inline]
     fn to_array(self: QM31) -> [M31; 4] {
         [self.a.a, self.a.b, self.b.a, self.b.b]
     }
+
     fn inverse(self: QM31) -> QM31 {
         assert_ne!(self, Zero::zero());
         let b2 = self.b * self.b;
@@ -43,6 +35,7 @@ pub impl QM31Impl of QM31Trait {
         let denom_inverse = denom.inverse();
         QM31 { a: self.a * denom_inverse, b: -self.b * denom_inverse }
     }
+
     fn mul_m31(self: QM31, multiplier: M31) -> QM31 {
         QM31 {
             a: CM31 { a: self.a.a * multiplier, b: self.a.b * multiplier },
@@ -139,15 +132,4 @@ mod tests {
         assert_eq!(qm1 * m.inverse().into(), qm1 * qm.inverse());
         assert_eq!(qm1.mul_m31(m), qm1 * m.into());
     }
-
-    #[test]
-    fn test_qm31_from_u32() {
-        let arr = [2147483648, 2, 3, 4];
-        let felt = QM31Impl::from_u32(arr);
-        let expected_felt = QM31 {
-            a: CM31 { a: m31(1), b: m31(2) }, b: CM31 { a: m31(3), b: m31(4) }
-        };
-
-        assert_eq!(felt, expected_felt)
-    }
 }