SIMD backend for poseidon252 merkle ops - CPU IMPL (#809)

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

@@ -4,6 +4,8 @@ mod circle;
 mod fri;
 mod grind;
 pub mod lookups;
+#[cfg(not(target_arch = "wasm32"))]
+mod poseidon252;
 pub mod quotients;
 
 use std::fmt::Debug;

crates/prover/src/core/backend/cpu/poseidon252.rs

@@ -0,0 +1,24 @@
+use itertools::Itertools;
+use starknet_ff::FieldElement as FieldElement252;
+
+use super::CpuBackend;
+use crate::core::fields::m31::BaseField;
+use crate::core::vcs::ops::{MerkleHasher, MerkleOps};
+use crate::core::vcs::poseidon252_merkle::Poseidon252MerkleHasher;
+
+impl MerkleOps<Poseidon252MerkleHasher> for CpuBackend {
+    fn commit_on_layer(
+        log_size: u32,
+        prev_layer: Option<&Vec<FieldElement252>>,
+        columns: &[&Vec<BaseField>],
+    ) -> Vec<FieldElement252> {
+        (0..(1 << log_size))
+            .map(|i| {
+                Poseidon252MerkleHasher::hash_node(
+                    prev_layer.map(|prev_layer| (prev_layer[2 * i], prev_layer[2 * i + 1])),
+                    &columns.iter().map(|column| column[i]).collect_vec(),
+                )
+            })
+            .collect()
+    }
+}

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

@@ -2,6 +2,8 @@ use serde::{Deserialize, Serialize};
 
 use super::{Backend, BackendForChannel};
 use crate::core::vcs::blake2_merkle::Blake2sMerkleChannel;
+#[cfg(not(target_arch = "wasm32"))]
+use crate::core::vcs::poseidon252_merkle::Poseidon252MerkleChannel;
 
 pub mod accumulation;
 pub mod bit_reverse;
@@ -15,6 +17,8 @@ pub mod fri;
 mod grind;
 pub mod lookups;
 pub mod m31;
+#[cfg(not(target_arch = "wasm32"))]
+pub mod poseidon252;
 pub mod prefix_sum;
 pub mod qm31;
 pub mod quotients;
@@ -26,3 +30,5 @@ pub struct SimdBackend;
 
 impl Backend for SimdBackend {}
 impl BackendForChannel<Blake2sMerkleChannel> for SimdBackend {}
+#[cfg(not(target_arch = "wasm32"))]
+impl BackendForChannel<Poseidon252MerkleChannel> for SimdBackend {}

crates/prover/src/core/backend/simd/poseidon252.rs

@@ -0,0 +1,36 @@
+use itertools::Itertools;
+use starknet_ff::FieldElement as FieldElement252;
+
+use super::SimdBackend;
+use crate::core::backend::{Col, Column, ColumnOps};
+use crate::core::fields::m31::BaseField;
+#[cfg(not(target_arch = "wasm32"))]
+use crate::core::vcs::ops::MerkleHasher;
+use crate::core::vcs::ops::MerkleOps;
+use crate::core::vcs::poseidon252_merkle::Poseidon252MerkleHasher;
+
+impl ColumnOps<FieldElement252> for SimdBackend {
+    type Column = Vec<FieldElement252>;
+
+    fn bit_reverse_column(_column: &mut Self::Column) {
+        unimplemented!()
+    }
+}
+
+impl MerkleOps<Poseidon252MerkleHasher> for SimdBackend {
+    // TODO(ShaharS): replace with SIMD implementation.
+    fn commit_on_layer(
+        log_size: u32,
+        prev_layer: Option<&Vec<FieldElement252>>,
+        columns: &[&Col<Self, BaseField>],
+    ) -> Vec<FieldElement252> {
+        (0..(1 << log_size))
+            .map(|i| {
+                Poseidon252MerkleHasher::hash_node(
+                    prev_layer.map(|prev_layer| (prev_layer[2 * i], prev_layer[2 * i + 1])),
+                    &columns.iter().map(|column| column.at(i)).collect_vec(),
+                )
+            })
+            .collect()
+    }
+}

crates/prover/src/core/vcs/poseidon252_merkle.rs

@@ -1,11 +1,9 @@
-use itertools::Itertools;
 use num_traits::Zero;
 use serde::{Deserialize, Serialize};
 use starknet_crypto::{poseidon_hash, poseidon_hash_many};
 use starknet_ff::FieldElement as FieldElement252;
 
-use super::ops::{MerkleHasher, MerkleOps};
-use crate::core::backend::CpuBackend;
+use super::ops::MerkleHasher;
 use crate::core::channel::{MerkleChannel, Poseidon252Channel};
 use crate::core::fields::m31::BaseField;
 use crate::core::vcs::hash::Hash;
@@ -46,23 +44,6 @@ impl MerkleHasher for Poseidon252MerkleHasher {
     }
 }
 
-impl MerkleOps<Poseidon252MerkleHasher> for CpuBackend {
-    fn commit_on_layer(
-        log_size: u32,
-        prev_layer: Option<&Vec<FieldElement252>>,
-        columns: &[&Vec<BaseField>],
-    ) -> Vec<FieldElement252> {
-        (0..(1 << log_size))
-            .map(|i| {
-                Poseidon252MerkleHasher::hash_node(
-                    prev_layer.map(|prev_layer| (prev_layer[2 * i], prev_layer[2 * i + 1])),
-                    &columns.iter().map(|column| column[i]).collect_vec(),
-                )
-            })
-            .collect()
-    }
-}
-
 impl Hash for FieldElement252 {}
 
 #[derive(Default)]

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

@@ -18,7 +18,7 @@ use crate::core::pcs::{CommitmentSchemeProver, PcsConfig, TreeSubspan};
 use crate::core::poly::circle::{CanonicCoset, CircleEvaluation, PolyOps};
 use crate::core::poly::BitReversedOrder;
 use crate::core::prover::{prove, StarkProof};
-use crate::core::vcs::blake2_merkle::Blake2sMerkleHasher;
+use crate::core::vcs::blake2_merkle::{Blake2sMerkleChannel, Blake2sMerkleHasher};
 use crate::core::{ColumnVec, InteractionElements};
 
 pub type PlonkComponent = FrameworkComponent<PlonkEval>;
@@ -182,7 +182,8 @@ pub fn prove_fibonacci_plonk(
 
     // Setup protocol.
     let channel = &mut Blake2sChannel::default();
-    let commitment_scheme = &mut CommitmentSchemeProver::new(config, &twiddles);
+    let commitment_scheme =
+        &mut CommitmentSchemeProver::<_, Blake2sMerkleChannel>::new(config, &twiddles);
 
     // Trace.
     let span = span!(Level::INFO, "Trace").entered();

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

@@ -23,7 +23,7 @@ use crate::core::pcs::{CommitmentSchemeProver, PcsConfig};
 use crate::core::poly::circle::{CanonicCoset, CircleEvaluation, PolyOps};
 use crate::core::poly::BitReversedOrder;
 use crate::core::prover::{prove, StarkProof};
-use crate::core::vcs::blake2_merkle::Blake2sMerkleHasher;
+use crate::core::vcs::blake2_merkle::{Blake2sMerkleChannel, Blake2sMerkleHasher};
 use crate::core::{ColumnVec, InteractionElements};
 
 const N_LOG_INSTANCES_PER_ROW: usize = 3;
@@ -336,7 +336,8 @@ pub fn prove_poseidon(
 
     // Setup protocol.
     let channel = &mut Blake2sChannel::default();
-    let commitment_scheme = &mut CommitmentSchemeProver::new(config, &twiddles);
+    let commitment_scheme =
+        &mut CommitmentSchemeProver::<_, Blake2sMerkleChannel>::new(config, &twiddles);
 
     // Trace.
     let span = span!(Level::INFO, "Trace").entered();

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

@@ -251,8 +251,6 @@ mod tests {
     #[cfg(not(target_arch = "wasm32"))]
     #[test_log::test]
     fn test_single_instance_wide_fib_prove_with_poseidon() {
-        use crate::core::backend::CpuBackend;
-
         const LOG_N_INSTANCES: u32 = 0;
         let config = PcsConfig::default();
         let component = WideFibComponent {

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

@@ -285,7 +285,8 @@ mod tests {
         span.exit();
         let channel = &mut Blake2sChannel::default();
         let air = SimdWideFibAir { component };
-        let proof = commit_and_prove(&air, channel, trace, config).unwrap();
+        let proof =
+            commit_and_prove::<_, Blake2sMerkleChannel>(&air, channel, trace, config).unwrap();
 
         let channel = &mut Blake2sChannel::default();
         commit_and_verify::<Blake2sMerkleChannel>(proof, &air, channel, config).unwrap();