Circuit constraint refinements to reduce proof size

src/circuit/gadget/ecc/chip/add_incomplete.rs

@@ -60,7 +60,8 @@ impl Config {
             // (y_r + y_q)(x_p − x_q) − (y_p − y_q)(x_q − x_r) = 0
             let poly2 = (y_r + y_q.clone()) * (x_p - x_q.clone()) - (y_p - y_q) * (x_q - x_r);
 
-            array::IntoIter::new([poly1, poly2]).map(move |poly| q_add_incomplete.clone() * poly)
+            array::IntoIter::new([("x_r", poly1), ("y_r", poly2)])
+                .map(move |(name, poly)| (name, q_add_incomplete.clone() * poly))
         });
     }
 

src/circuit/gadget/ecc/chip/mul.rs

@@ -99,12 +99,12 @@ impl Config {
         meta.create_gate("LSB check", |meta| {
             let q_mul_lsb = meta.query_selector(self.q_mul_lsb);
 
-            let z_1 = meta.query_advice(self.complete_config.z_complete, Rotation::prev());
-            let z_0 = meta.query_advice(self.complete_config.z_complete, Rotation::cur());
-            let x_p = meta.query_advice(self.add_config.x_p, Rotation::prev());
-            let y_p = meta.query_advice(self.add_config.y_p, Rotation::prev());
-            let base_x = meta.query_advice(self.add_config.x_p, Rotation::cur());
-            let base_y = meta.query_advice(self.add_config.y_p, Rotation::cur());
+            let z_1 = meta.query_advice(self.complete_config.z_complete, Rotation::cur());
+            let z_0 = meta.query_advice(self.complete_config.z_complete, Rotation::next());
+            let x_p = meta.query_advice(self.add_config.x_p, Rotation::cur());
+            let y_p = meta.query_advice(self.add_config.y_p, Rotation::cur());
+            let base_x = meta.query_advice(self.add_config.x_p, Rotation::next());
+            let base_y = meta.query_advice(self.add_config.y_p, Rotation::next());
 
             //    z_0 = 2 * z_1 + k_0
             // => k_0 = z_0 - 2 * z_1
@@ -118,8 +118,12 @@ impl Config {
             let lsb_x = (lsb.clone() * x_p.clone()) + one_minus_lsb.clone() * (x_p - base_x);
             let lsb_y = (lsb * y_p.clone()) + one_minus_lsb * (y_p + base_y);
 
-            std::array::IntoIter::new([bool_check, lsb_x, lsb_y])
-                .map(move |poly| q_mul_lsb.clone() * poly)
+            std::array::IntoIter::new([
+                ("bool_check", bool_check),
+                ("lsb_x", lsb_x),
+                ("lsb_y", lsb_y),
+            ])
+            .map(move |(name, poly)| (name, q_mul_lsb.clone() * poly))
         });
 
         self.hi_config.create_gate(meta);
@@ -271,8 +275,8 @@ impl Config {
     /// addition subregion.
     ///
     /// ```text
-    /// | x_p  | y_p  | acc_x | acc_y | complete addition  | z_1 |
-    /// |base_x|base_y| res_x | res_y |   |   |    |   |   | z_0 | q_mul_lsb = 1
+    /// | x_p  | y_p  | acc_x | acc_y | complete addition  | z_1 | q_mul_lsb = 1
+    /// |base_x|base_y| res_x | res_y |   |   |    |   |   | z_0 |
     /// ```
     fn process_lsb(
         &self,
@@ -284,7 +288,7 @@ impl Config {
         lsb: Option<bool>,
     ) -> Result<(EccPoint, Z<pallas::Base>), Error> {
         // Enforce switching logic on LSB using a custom gate
-        self.q_mul_lsb.enable(region, offset + 1)?;
+        self.q_mul_lsb.enable(region, offset)?;
 
         // z_1 has been assigned at (z_complete, offset).
         // Assign z_0 = 2⋅z_1 + k_0

src/circuit/gadget/ecc/chip/mul/complete.rs

@@ -42,6 +42,11 @@ impl Config {
     /// addition gate (controlled by `q_mul`) already checks scalar decomposition for
     /// the other bits.
     pub(super) fn create_gate(&self, meta: &mut ConstraintSystem<pallas::Base>) {
+        // | y_p | z_complete |
+        // --------------------
+        // | y_p | z_{i + 1}  |
+        // |     | base_y     |
+        // |     | z_i        |
         meta.create_gate(
             "Decompose scalar for complete bits of variable-base mul",
             |meta| {
@@ -122,6 +127,12 @@ impl Config {
             // Each iteration uses 2 rows (two complete additions)
             let row = 2 * iter;
 
+            // | x_p | y_p | x_qr  | y_qr  | z_complete |
+            // ------------------------------------------
+            // | U_x | U_y | acc_x | acc_y | z_{i + 1}  | row + offset
+            // |acc_x|acc_y|acc+U_x|acc+U_y| base_y     |
+            // |     |     | res_x | res_y | z_i        |
+
             // Update `z`.
             z = {
                 // z_next = z_cur * 2 + k_next

src/circuit/gadget/ecc/chip/mul/overflow.rs

@@ -81,12 +81,12 @@ impl Config {
             let canonicity = (one.clone() - k_254) * (one - z_130 * eta) * s_minus_lo_130;
 
             iter::empty()
-                .chain(Some(s_check))
-                .chain(Some(recovery))
-                .chain(Some(lo_zero))
-                .chain(Some(s_minus_lo_130_check))
-                .chain(Some(canonicity))
-                .map(|poly| q_mul_overflow.clone() * poly)
+                .chain(Some(("s_check", s_check)))
+                .chain(Some(("recovery", recovery)))
+                .chain(Some(("lo_zero", lo_zero)))
+                .chain(Some(("s_minus_lo_130_check", s_minus_lo_130_check)))
+                .chain(Some(("canonicity", canonicity)))
+                .map(|(name, poly)| (name, q_mul_overflow.clone() * poly))
                 .collect::<Vec<_>>()
         });
     }

src/circuit/gadget/ecc/chip/witness_point.rs

@@ -45,8 +45,8 @@ impl Config {
                 - Expression::Constant(pallas::Affine::b());
 
             vec![
-                q_point.clone() * x * curve_eqn.clone(),
-                q_point * y * curve_eqn,
+                ("x == 0 ∨ on_curve", q_point.clone() * x * curve_eqn.clone()),
+                ("y == 0 ∨ on_curve", q_point * y * curve_eqn),
             ]
         });
     }

src/circuit/gadget/poseidon/pow5t3.rs

@@ -110,10 +110,14 @@ impl<F: FieldExt> Pow5T3Chip<F> {
                         - next[next_idx].clone())
             };
 
-            vec![full_round(0), full_round(1), full_round(2)]
+            vec![
+                ("state[0]", full_round(0)),
+                ("state[1]", full_round(1)),
+                ("state[2]", full_round(2)),
+            ]
         });
 
-        meta.create_gate("partial round", |meta| {
+        meta.create_gate("partial rounds", |meta| {
             let cur_0 = meta.query_advice(state[0], Rotation::cur());
             let cur_1 = meta.query_advice(state[1], Rotation::cur());
             let cur_2 = meta.query_advice(state[2], Rotation::cur());
@@ -143,18 +147,24 @@ impl<F: FieldExt> Pow5T3Chip<F> {
             };
 
             vec![
-                s_partial.clone() * (pow_5(cur_0 + rc_a0) - mid_0.clone()),
-                s_partial.clone()
-                    * (pow_5(
-                        mid_0.clone() * m_reg[0][0]
-                            + (cur_1.clone() + rc_a1.clone()) * m_reg[0][1]
-                            + (cur_2.clone() + rc_a2.clone()) * m_reg[0][2]
-                            + rc_b0,
-                    ) - (next_0.clone() * m_inv[0][0]
-                        + next_1.clone() * m_inv[0][1]
-                        + next_2.clone() * m_inv[0][2])),
-                partial_round_linear(1, rc_b1),
-                partial_round_linear(2, rc_b2),
+                (
+                    "state[0] round a",
+                    s_partial.clone() * (pow_5(cur_0 + rc_a0) - mid_0.clone()),
+                ),
+                (
+                    "state[0] round b",
+                    s_partial.clone()
+                        * (pow_5(
+                            mid_0.clone() * m_reg[0][0]
+                                + (cur_1.clone() + rc_a1.clone()) * m_reg[0][1]
+                                + (cur_2.clone() + rc_a2.clone()) * m_reg[0][2]
+                                + rc_b0,
+                        ) - (next_0.clone() * m_inv[0][0]
+                            + next_1.clone() * m_inv[0][1]
+                            + next_2.clone() * m_inv[0][2])),
+                ),
+                ("state[1]", partial_round_linear(1, rc_b1)),
+                ("state[2]", partial_round_linear(2, rc_b2)),
             ]
         });
 
@@ -177,10 +187,19 @@ impl<F: FieldExt> Pow5T3Chip<F> {
             };
 
             vec![
-                pad_and_add(initial_state_0, input_0, output_state_0),
-                pad_and_add(initial_state_1, input_1, output_state_1),
+                (
+                    "state[0]",
+                    pad_and_add(initial_state_0, input_0, output_state_0),
+                ),
+                (
+                    "state[1]",
+                    pad_and_add(initial_state_1, input_1, output_state_1),
+                ),
                 // The capacity element is never altered by the input.
-                s_pad_and_add * (initial_state_2 - output_state_2),
+                (
+                    "state[2]",
+                    s_pad_and_add * (initial_state_2 - output_state_2),
+                ),
             ]
         });
 

src/circuit/gadget/sinsemilla/commit_ivk.rs

@@ -59,8 +59,8 @@ impl CommitIvkConfig {
 
             |  A_0  |  A_1  |  A_2  |  A_3  |  A_4  |  A_5  |  A_6  |    A_7    |       A_8      | q_commit_ivk |
             -----------------------------------------------------------------------------------------------------
-            |   ak  |   a   |   b   |  b_0  |  b_1  |  b_2  | z13_a |  a_prime  |   z13_a_prime  |       0      |
-            |   nk  |   c   |   d   |  d_0  |  d_1  |       | z13_c | b2_c_prime| z14_b2_c_prime |       1      |
+            |   ak  |   a   |   b   |  b_0  |  b_1  |  b_2  | z13_a |  a_prime  |   z13_a_prime  |       1      |
+            |   nk  |   c   |   d   |  d_0  |  d_1  |       | z13_c | b2_c_prime| z14_b2_c_prime |       0      |
 
         */
         meta.create_gate("CommitIvk canonicity check", |meta| {
@@ -73,37 +73,37 @@ impl CommitIvkConfig {
             let two_pow_250 = pallas::Base::from_u128(1 << 125).square();
             let two_pow_254 = two_pow_250 * two_pow_4;
 
-            let ak = meta.query_advice(config.advices[0], Rotation::prev());
-            let nk = meta.query_advice(config.advices[0], Rotation::cur());
+            let ak = meta.query_advice(config.advices[0], Rotation::cur());
+            let nk = meta.query_advice(config.advices[0], Rotation::next());
 
             // `a` is constrained by the Sinsemilla hash to be 250 bits.
-            let a = meta.query_advice(config.advices[1], Rotation::prev());
+            let a = meta.query_advice(config.advices[1], Rotation::cur());
             // `b` is constrained by the Sinsemilla hash to be 10 bits.
-            let b_whole = meta.query_advice(config.advices[2], Rotation::prev());
+            let b_whole = meta.query_advice(config.advices[2], Rotation::cur());
             // `c` is constrained by the Sinsemilla hash to be 240 bits.
-            let c = meta.query_advice(config.advices[1], Rotation::cur());
+            let c = meta.query_advice(config.advices[1], Rotation::next());
             // `d` is constrained by the Sinsemilla hash to be 10 bits.
-            let d_whole = meta.query_advice(config.advices[2], Rotation::cur());
+            let d_whole = meta.query_advice(config.advices[2], Rotation::next());
 
             // b = b_0||b_1||b_2`
             //   = (bits 250..=253 of `ak`) || (bit 254 of  `ak`) || (bits 0..=4 of  `nk`)
             //
             // b_0 has been constrained outside this gate to be a four-bit value.
-            let b_0 = meta.query_advice(config.advices[3], Rotation::prev());
+            let b_0 = meta.query_advice(config.advices[3], Rotation::cur());
             // This gate constrains b_1 to be a one-bit value.
-            let b_1 = meta.query_advice(config.advices[4], Rotation::prev());
+            let b_1 = meta.query_advice(config.advices[4], Rotation::cur());
             // b_2 has been constrained outside this gate to be a five-bit value.
-            let b_2 = meta.query_advice(config.advices[5], Rotation::prev());
+            let b_2 = meta.query_advice(config.advices[5], Rotation::cur());
             // Check that b_whole is consistent with the witnessed subpieces.
             let b_decomposition_check =
                 b_whole - (b_0.clone() + b_1.clone() * two_pow_4 + b_2.clone() * two_pow_5);
 
             // d = d_0||d_1` = (bits 245..=253 of `nk`) || (bit 254 of `nk`)
             //
             // d_0 has been constrained outside this gate to be a nine-bit value.
-            let d_0 = meta.query_advice(config.advices[3], Rotation::cur());
+            let d_0 = meta.query_advice(config.advices[3], Rotation::next());
             // This gate constrains d_1 to be a one-bit value.
-            let d_1 = meta.query_advice(config.advices[4], Rotation::cur());
+            let d_1 = meta.query_advice(config.advices[4], Rotation::next());
             // Check that d_whole is consistent with the witnessed subpieces.
             let d_decomposition_check = d_whole - (d_0.clone() + d_1.clone() * two_pow_9);
 
@@ -137,14 +137,14 @@ impl CommitIvkConfig {
                 // z13_a is the 13th running sum output by the 10-bit Sinsemilla decomposition of `a`.
                 // b_1 = 1 => z13_a = 0
                 let z13_a_check = {
-                    let z13_a = meta.query_advice(config.advices[6], Rotation::prev());
+                    let z13_a = meta.query_advice(config.advices[6], Rotation::cur());
                     b_1.clone() * z13_a
                 };
 
                 // Check that a_prime = a + 2^130 - t_P.
                 // This is checked regardless of the value of b_1.
                 let a_prime_check = {
-                    let a_prime = meta.query_advice(config.advices[7], Rotation::prev());
+                    let a_prime = meta.query_advice(config.advices[7], Rotation::cur());
                     let two_pow_130 =
                         Expression::Constant(pallas::Base::from_u128(1 << 65).square());
                     let t_p = Expression::Constant(pallas::Base::from_u128(T_P));
@@ -154,15 +154,15 @@ impl CommitIvkConfig {
                 // Check that the running sum output by the 130-bit little-endian decomposition of
                 // `a_prime` is zero.
                 let z13_a_prime = {
-                    let z13_a_prime = meta.query_advice(config.advices[8], Rotation::prev());
+                    let z13_a_prime = meta.query_advice(config.advices[8], Rotation::cur());
                     b_1 * z13_a_prime
                 };
 
                 std::iter::empty()
-                    .chain(Some(b0_canon_check))
-                    .chain(Some(z13_a_check))
-                    .chain(Some(a_prime_check))
-                    .chain(Some(z13_a_prime))
+                    .chain(Some(("b0_canon_check", b0_canon_check)))
+                    .chain(Some(("z13_a_check", z13_a_check)))
+                    .chain(Some(("a_prime_check", a_prime_check)))
+                    .chain(Some(("z13_a_prime", z13_a_prime)))
             };
 
             // nk = b_2 (5 bits) || c (240 bits) || d_0 (9 bits) || d_1 (1 bit)
@@ -174,7 +174,7 @@ impl CommitIvkConfig {
                 // d_1 = 1 => z13_c = 0, where z13_c is the 13th running sum
                 // output by the 10-bit Sinsemilla decomposition of `c`.
                 let z13_c_check = {
-                    let z13_c = meta.query_advice(config.advices[6], Rotation::cur());
+                    let z13_c = meta.query_advice(config.advices[6], Rotation::next());
                     d_1.clone() * z13_c
                 };
 
@@ -185,34 +185,34 @@ impl CommitIvkConfig {
                     let two_pow_140 =
                         Expression::Constant(pallas::Base::from_u128(1 << 70).square());
                     let t_p = Expression::Constant(pallas::Base::from_u128(T_P));
-                    let b2_c_prime = meta.query_advice(config.advices[7], Rotation::cur());
+                    let b2_c_prime = meta.query_advice(config.advices[7], Rotation::next());
                     b_2 + c * two_pow_5 + two_pow_140 - t_p - b2_c_prime
                 };
 
                 // Check that the running sum output by the 140-bit little-
                 // endian decomposition of b2_c_prime is zero.
                 let z14_b2_c_prime = {
-                    let z14_b2_c_prime = meta.query_advice(config.advices[8], Rotation::cur());
+                    let z14_b2_c_prime = meta.query_advice(config.advices[8], Rotation::next());
                     d_1 * z14_b2_c_prime
                 };
 
                 std::iter::empty()
-                    .chain(Some(c0_canon_check))
-                    .chain(Some(z13_c_check))
-                    .chain(Some(b2_c_prime_check))
-                    .chain(Some(z14_b2_c_prime))
+                    .chain(Some(("c0_canon_check", c0_canon_check)))
+                    .chain(Some(("z13_c_check", z13_c_check)))
+                    .chain(Some(("b2_c_prime_check", b2_c_prime_check)))
+                    .chain(Some(("z14_b2_c_prime", z14_b2_c_prime)))
             };
 
             std::iter::empty()
-                .chain(Some(b1_bool_check))
-                .chain(Some(d1_bool_check))
-                .chain(Some(b_decomposition_check))
-                .chain(Some(d_decomposition_check))
-                .chain(Some(ak_decomposition_check))
-                .chain(Some(nk_decomposition_check))
+                .chain(Some(("b1_bool_check", b1_bool_check)))
+                .chain(Some(("d1_bool_check", d1_bool_check)))
+                .chain(Some(("b_decomposition_check", b_decomposition_check)))
+                .chain(Some(("d_decomposition_check", d_decomposition_check)))
+                .chain(Some(("ak_decomposition_check", ak_decomposition_check)))
+                .chain(Some(("nk_decomposition_check", nk_decomposition_check)))
                 .chain(ak_canonicity_checks)
                 .chain(nk_canonicity_checks)
-                .map(move |poly| q_commit_ivk.clone() * poly)
+                .map(move |(name, poly)| (name, q_commit_ivk.clone() * poly))
         });
 
         config
@@ -455,8 +455,8 @@ impl CommitIvkConfig {
 
         |  A_0  |  A_1  |  A_2  |  A_3  |  A_4  |  A_5  |  A_6  |    A_7    |       A_8      | q_commit_ivk |
         -----------------------------------------------------------------------------------------------------
-        |   ak  |   a   |   b   |  b_0  |  b_1  |  b_2  | z13_a |  a_prime  |   z13_a_prime  |       0      |
-        |   nk  |   c   |   d   |  d_0  |  d_1  |       | z13_c | b2_c_prime| z14_b2_c_prime |       1      |
+        |   ak  |   a   |   b   |  b_0  |  b_1  |  b_2  | z13_a |  a_prime  |   z13_a_prime  |       1      |
+        |   nk  |   c   |   d   |  d_0  |  d_1  |       | z13_c | b2_c_prime| z14_b2_c_prime |       0      |
 
     */
     fn assign_gate(
@@ -467,8 +467,8 @@ impl CommitIvkConfig {
         layouter.assign_region(
             || "Assign cells used in canonicity gate",
             |mut region| {
-                // Enable selector on offset 1
-                self.q_commit_ivk.enable(&mut region, 1)?;
+                // Enable selector on offset 0
+                self.q_commit_ivk.enable(&mut region, 0)?;
 
                 // Offset 0
                 {