Create phase number constants.

crates/prover/src/core/air/air_ext.rs

@@ -8,6 +8,7 @@ use crate::core::fields::qm31::SecureField;
 use crate::core::fields::secure_column::SECURE_EXTENSION_DEGREE;
 use crate::core::pcs::{CommitmentTreeProver, TreeVec};
 use crate::core::poly::circle::SecureCirclePoly;
+use crate::core::prover::{BASE_TRACE, INTERACTION_TRACE};
 use crate::core::vcs::blake2_merkle::Blake2sMerkleHasher;
 use crate::core::vcs::ops::MerkleOps;
 use crate::core::{ColumnVec, ComponentVec, InteractionElements, LookupValues};
@@ -37,8 +38,8 @@ pub trait AirExt: Air {
         let mut interaction_component_points = vec![];
         for component in self.components() {
             let points = component.mask_points(point);
-            trace_component_points.extend(points[0].clone());
-            interaction_component_points.extend(points[1].clone());
+            trace_component_points.extend(points[BASE_TRACE].clone());
+            interaction_component_points.extend(points[INTERACTION_TRACE].clone());
         }
         let mut points = TreeVec::new(vec![trace_component_points]);
         if !interaction_component_points
@@ -78,8 +79,8 @@ pub trait AirExt: Air {
         let mut interaction_tree = vec![];
         self.components().iter().for_each(|component| {
             let bounds = component.trace_log_degree_bounds();
-            trace_tree.extend(bounds[0].clone());
-            interaction_tree.extend(bounds[1].clone());
+            trace_tree.extend(bounds[BASE_TRACE].clone());
+            interaction_tree.extend(bounds[INTERACTION_TRACE].clone());
         });
         let mut sizes = TreeVec::new(vec![trace_tree]);
         if !interaction_tree.is_empty() {
@@ -92,11 +93,11 @@ pub trait AirExt: Air {
         &'a self,
         trees: &'a [CommitmentTreeProver<B>],
     ) -> Vec<ComponentTrace<'_, B>> {
-        let poly_iter = &mut trees[0].polynomials.iter();
-        let eval_iter = &mut trees[0].evaluations.iter();
+        let poly_iter = &mut trees[BASE_TRACE].polynomials.iter();
+        let eval_iter = &mut trees[BASE_TRACE].evaluations.iter();
         let mut component_traces = vec![];
         self.components().iter().for_each(|component| {
-            let n_columns = component.trace_log_degree_bounds()[0].len();
+            let n_columns = component.trace_log_degree_bounds()[BASE_TRACE].len();
             let polys = poly_iter.take(n_columns).collect_vec();
             let evals = eval_iter.take(n_columns).collect_vec();
 
@@ -107,13 +108,13 @@ pub trait AirExt: Air {
         });
 
         if trees.len() > 1 {
-            let poly_iter = &mut trees[1].polynomials.iter();
-            let eval_iter = &mut trees[1].evaluations.iter();
+            let poly_iter = &mut trees[INTERACTION_TRACE].polynomials.iter();
+            let eval_iter = &mut trees[INTERACTION_TRACE].evaluations.iter();
             self.components()
                 .iter()
                 .zip_eq(&mut component_traces)
                 .for_each(|(component, component_trace)| {
-                    let n_columns = component.trace_log_degree_bounds()[1].len();
+                    let n_columns = component.trace_log_degree_bounds()[INTERACTION_TRACE].len();
                     let polys = poly_iter.take(n_columns).collect_vec();
                     let evals = eval_iter.take(n_columns).collect_vec();
                     component_trace.polys.push(polys);

crates/prover/src/core/prover/mod.rs

@@ -36,6 +36,9 @@ pub const LOG_LAST_LAYER_DEGREE_BOUND: u32 = 0;
 pub const PROOF_OF_WORK_BITS: u32 = 12;
 pub const N_QUERIES: usize = 3;
 
+pub const BASE_TRACE: usize = 0;
+pub const INTERACTION_TRACE: usize = 1;
+
 #[derive(Debug)]
 pub struct StarkProof {
     pub commitments: TreeVec<<ChannelHasher as Hasher>::Hash>,
@@ -205,11 +208,19 @@ pub fn verify(
     // Read trace commitment.
     let mut commitment_scheme = CommitmentSchemeVerifier::new();
     let column_log_sizes = air.column_log_sizes();
-    commitment_scheme.commit(proof.commitments[0], &column_log_sizes[0], channel);
+    commitment_scheme.commit(
+        proof.commitments[BASE_TRACE],
+        &column_log_sizes[BASE_TRACE],
+        channel,
+    );
     let interaction_elements = air.interaction_elements(channel);
 
     if air.n_interaction_phases() == 2 {
-        commitment_scheme.commit(proof.commitments[1], &column_log_sizes[1], channel);
+        commitment_scheme.commit(
+            proof.commitments[INTERACTION_TRACE],
+            &column_log_sizes[INTERACTION_TRACE],
+            channel,
+        );
     }
 
     channel.mix_felts(
@@ -272,7 +283,7 @@ fn sampled_values_to_mask(
         .iter();
     let mut trace_oods_values = vec![];
     air.components().iter().for_each(|component| {
-        let n_trace_points = component.mask_points(CirclePoint::zero())[0].len();
+        let n_trace_points = component.mask_points(CirclePoint::zero())[BASE_TRACE].len();
         trace_oods_values.push(
             flat_trace_values
                 .take(n_trace_points)
@@ -291,7 +302,8 @@ fn sampled_values_to_mask(
             .iter()
             .zip_eq(&mut trace_oods_values)
             .for_each(|(component, values)| {
-                let n_interaction_points = component.mask_points(CirclePoint::zero())[1].len();
+                let n_interaction_points =
+                    component.mask_points(CirclePoint::zero())[INTERACTION_TRACE].len();
                 values.extend(
                     interaction_values
                         .take(n_interaction_points)

crates/prover/src/examples/fibonacci/component.rs

@@ -14,6 +14,7 @@ use crate::core::fields::{ExtensionOf, FieldExpOps};
 use crate::core::pcs::TreeVec;
 use crate::core::poly::circle::{CanonicCoset, CircleEvaluation};
 use crate::core::poly::BitReversedOrder;
+use crate::core::prover::BASE_TRACE;
 use crate::core::utils::bit_reverse_index;
 use crate::core::{ColumnVec, InteractionElements, LookupValues};
 
@@ -145,7 +146,7 @@ impl ComponentProver<CpuBackend> for FibonacciComponent {
         _interaction_elements: &InteractionElements,
         _lookup_values: &LookupValues,
     ) {
-        let poly = &trace.polys[0][0];
+        let poly = &trace.polys[BASE_TRACE][0];
         let trace_domain = CanonicCoset::new(self.log_size);
         let trace_eval_domain = CanonicCoset::new(self.log_size + 1).circle_domain();
         let trace_eval = poly.evaluate(trace_eval_domain).bit_reverse();

crates/prover/src/examples/fibonacci/mod.rs

@@ -125,7 +125,7 @@ mod tests {
     use crate::core::fields::qm31::SecureField;
     use crate::core::pcs::TreeVec;
     use crate::core::poly::circle::CanonicCoset;
-    use crate::core::prover::VerificationError;
+    use crate::core::prover::{VerificationError, BASE_TRACE};
     use crate::core::queries::Queries;
     use crate::core::utils::bit_reverse;
     use crate::core::{InteractionElements, LookupValues};
@@ -167,7 +167,7 @@ mod tests {
         let point = CirclePoint::<SecureField>::get_point(98989892);
 
         let points = fib.air.mask_points(point);
-        let mask_values = zip(&component_traces[0].polys[0], &points[0])
+        let mask_values = zip(&component_traces[0].polys[BASE_TRACE], &points[0])
             .map(|(poly, points)| {
                 points
                     .iter()
@@ -238,7 +238,8 @@ mod tests {
         let fib = Fibonacci::new(FIB_LOG_SIZE, m31!(443693538));
 
         let mut invalid_proof = fib.prove().unwrap();
-        invalid_proof.commitment_scheme_proof.queried_values.0[0][0][3] += BaseField::one();
+        invalid_proof.commitment_scheme_proof.queried_values.0[BASE_TRACE][0][3] +=
+            BaseField::one();
 
         let error = fib.verify(invalid_proof).unwrap_err();
         assert_matches!(error, VerificationError::Merkle(_));
@@ -268,7 +269,7 @@ mod tests {
         let fib = Fibonacci::new(FIB_LOG_SIZE, m31!(443693538));
 
         let mut invalid_proof = fib.prove().unwrap();
-        invalid_proof.commitment_scheme_proof.queried_values.0[0][0].pop();
+        invalid_proof.commitment_scheme_proof.queried_values.0[BASE_TRACE][0].pop();
 
         let error = fib.verify(invalid_proof).unwrap_err();
         assert_matches!(error, VerificationError::Merkle(_));

crates/prover/src/examples/wide_fibonacci/constraint_eval.rs

@@ -23,6 +23,7 @@ use crate::core::fields::FieldExpOps;
 use crate::core::pcs::TreeVec;
 use crate::core::poly::circle::{CanonicCoset, CircleDomain, CircleEvaluation, SecureCirclePoly};
 use crate::core::poly::BitReversedOrder;
+use crate::core::prover::{BASE_TRACE, INTERACTION_TRACE};
 use crate::core::utils::{
     bit_reverse, previous_bit_reversed_circle_domain_index, shifted_secure_combination,
 };
@@ -95,13 +96,13 @@ impl WideFibComponent {
         #[allow(clippy::needless_range_loop)]
         for i in 0..trace_eval_domain.size() {
             first_point_numerators[i] = accum.random_coeff_powers[self.n_columns() + 4]
-                * (trace_evals[0][0][i] - lookup_value_0)
+                * (trace_evals[BASE_TRACE][0][i] - lookup_value_0)
                 + accum.random_coeff_powers[self.n_columns() + 3]
-                    * (trace_evals[0][1][i] - lookup_value_1);
+                    * (trace_evals[BASE_TRACE][1][i] - lookup_value_1);
             last_point_numerators[i] = accum.random_coeff_powers[self.n_columns() + 2]
-                * (trace_evals[0][self.n_columns() - 2][i] - lookup_value_n_minus_2)
+                * (trace_evals[BASE_TRACE][self.n_columns() - 2][i] - lookup_value_n_minus_2)
                 + accum.random_coeff_powers[self.n_columns() + 1]
-                    * (trace_evals[0][self.n_columns() - 1][i] - lookup_value_n_minus_1);
+                    * (trace_evals[BASE_TRACE][self.n_columns() - 1][i] - lookup_value_n_minus_1);
         }
         for (i, (num, denom_inverse)) in first_point_numerators
             .iter()
@@ -140,8 +141,9 @@ impl WideFibComponent {
         for i in 0..trace_eval_domain.size() {
             for j in 0..self.n_columns() - 2 {
                 numerators[i] += accum.random_coeff_powers[self.n_columns() - 3 - j]
-                    * (trace_evals[0][j][i].square() + trace_evals[0][j + 1][i].square()
-                        - trace_evals[0][j + 2][i]);
+                    * (trace_evals[BASE_TRACE][j][i].square()
+                        + trace_evals[BASE_TRACE][j + 1][i].square()
+                        - trace_evals[BASE_TRACE][j + 2][i]);
             }
         }
         for (i, (num, denom_inverse)) in numerators.iter().zip(denom_inverses.iter()).enumerate() {
@@ -185,20 +187,20 @@ impl WideFibComponent {
         for i in 0..trace_eval_domain.size() {
             let value =
                 SecureCirclePoly::<CpuBackend>::eval_from_partial_evals(std::array::from_fn(|j| {
-                    trace_evals[1][j][i].into()
+                    trace_evals[INTERACTION_TRACE][j][i].into()
                 }));
             first_point_numerators[i] = accum.random_coeff_powers[self.n_columns() - 1]
                 * ((value
                     * shifted_secure_combination(
                         &[
-                            trace_evals[0][self.n_columns() - 2][i],
-                            trace_evals[0][self.n_columns() - 1][i],
+                            trace_evals[BASE_TRACE][self.n_columns() - 2][i],
+                            trace_evals[BASE_TRACE][self.n_columns() - 1][i],
                         ],
                         alpha,
                         z,
                     ))
                     - shifted_secure_combination(
-                        &[trace_evals[0][0][i], trace_evals[0][1][i]],
+                        &[trace_evals[BASE_TRACE][0][i], trace_evals[BASE_TRACE][1][i]],
                         alpha,
                         z,
                     ));
@@ -253,7 +255,7 @@ impl WideFibComponent {
         for i in 0..trace_eval_domain.size() {
             let value =
                 SecureCirclePoly::<CpuBackend>::eval_from_partial_evals(std::array::from_fn(|j| {
-                    trace_evals[1][j][i].into()
+                    trace_evals[INTERACTION_TRACE][j][i].into()
                 }));
             let prev_index = previous_bit_reversed_circle_domain_index(
                 i,
@@ -262,21 +264,21 @@ impl WideFibComponent {
             );
             let prev_value =
                 SecureCirclePoly::<CpuBackend>::eval_from_partial_evals(std::array::from_fn(|j| {
-                    trace_evals[1][j][prev_index].into()
+                    trace_evals[INTERACTION_TRACE][j][prev_index].into()
                 }));
             numerators[i] = accum.random_coeff_powers[self.n_columns()]
                 * ((value
                     * shifted_secure_combination(
                         &[
-                            trace_evals[0][self.n_columns() - 2][i],
-                            trace_evals[0][self.n_columns() - 1][i],
+                            trace_evals[BASE_TRACE][self.n_columns() - 2][i],
+                            trace_evals[BASE_TRACE][self.n_columns() - 1][i],
                         ],
                         alpha,
                         z,
                     ))
                     - (prev_value
                         * shifted_secure_combination(
-                            &[trace_evals[0][0][i], trace_evals[0][1][i]],
+                            &[trace_evals[BASE_TRACE][0][i], trace_evals[BASE_TRACE][1][i]],
                             alpha,
                             z,
                         )));
@@ -336,7 +338,7 @@ impl ComponentProver<CpuBackend> for WideFibComponent {
 
     fn lookup_values(&self, trace: &ComponentTrace<'_, CpuBackend>) -> LookupValues {
         let domain = CanonicCoset::new(self.log_column_size());
-        let trace_poly = &trace.polys[0];
+        let trace_poly = &trace.polys[BASE_TRACE];
         let values = BTreeMap::from_iter([
             (
                 LOOKUP_VALUE_0_ID.to_string(),

crates/prover/src/examples/wide_fibonacci/simd.rs

@@ -23,6 +23,7 @@ use crate::core::fields::{FieldExpOps, FieldOps};
 use crate::core::pcs::TreeVec;
 use crate::core::poly::circle::{CanonicCoset, CircleEvaluation};
 use crate::core::poly::BitReversedOrder;
+use crate::core::prover::BASE_TRACE;
 use crate::core::{ColumnVec, InteractionElements, LookupValues};
 use crate::examples::wide_fibonacci::component::{ALPHA_ID, N_COLUMNS, Z_ID};
 
@@ -179,7 +180,7 @@ impl ComponentProver<SimdBackend> for SimdWideFibComponent {
         _interaction_elements: &InteractionElements,
         _lookup_values: &LookupValues,
     ) {
-        assert_eq!(trace.polys[0].len(), self.n_columns());
+        assert_eq!(trace.polys[BASE_TRACE].len(), self.n_columns());
         // TODO(spapini): Steal evaluation from commitment.
         let eval_domain = CanonicCoset::new(self.log_column_size() + 1).circle_domain();
         let trace_eval = &trace.evals;
@@ -204,14 +205,14 @@ impl ComponentProver<SimdBackend> for SimdWideFibComponent {
 
         for vec_row in 0..(1 << (eval_domain.log_size() - LOG_N_LANES)) {
             // Numerator.
-            let a = trace_eval[0][0].data[vec_row];
+            let a = trace_eval[BASE_TRACE][0].data[vec_row];
             let mut row_res = PackedSecureField::zero();
             let mut a_sq = a.square();
-            let mut b_sq = trace_eval[0][1].data[vec_row].square();
+            let mut b_sq = trace_eval[BASE_TRACE][1].data[vec_row].square();
             #[allow(clippy::needless_range_loop)]
             for i in 0..(self.n_columns() - 2) {
                 unsafe {
-                    let c = *trace_eval[0]
+                    let c = *trace_eval[BASE_TRACE]
                         .get_unchecked(i + 2)
                         .data
                         .get_unchecked(vec_row);