mem squish

stwo_cairo_prover/crates/prover/src/cairo_air/debug.rs

@@ -477,7 +477,7 @@ pub fn track_cairo_relations(
         RelationTrackerComponent::new(
             tree_span_provider,
             memory_address_to_id::Eval {
-                log_n_rows: claim.memory_address_to_id.log_size,
+                log_size: claim.memory_address_to_id.log_size,
                 lookup_elements: relations::MemoryAddressToId::dummy(),
             },
             1 << claim.memory_address_to_id.log_size,

stwo_cairo_prover/crates/prover/src/components/memory/memory_address_to_id/component.rs

@@ -3,52 +3,69 @@ use stwo_prover::constraint_framework::{
     EvalAtRow, FrameworkComponent, FrameworkEval, RelationEntry,
 };
 use stwo_prover::core::channel::Channel;
+use stwo_prover::core::fields::m31::M31;
 use stwo_prover::core::fields::qm31::SecureField;
 use stwo_prover::core::fields::secure_column::SECURE_EXTENSION_DEGREE;
 use stwo_prover::core::pcs::TreeVec;
 
 use crate::relations;
 
-pub const N_ADDR_TO_ID_COLUMNS: usize = 3;
+// TODO(Ohad): Address should be a preprocessed `seq`.
+pub const N_ADDR_COLUMNS: usize = 1;
+
+// Split the (ID , Multiplicity) columns to shorter chunks. This is done to improve the performance
+// during The merkle commitment and FRI, as this component is usually the tallest in the Cairo AIR.
+// TODO(Ohad): Change split to 8 after seq is implemented. NOTE: it is possible to split further
+// with an expansion trick similar to the one used in XOR. Investigate if it is worth it.
+pub(super) const LOG_SPLIT_SIZE: u32 = 2;
+pub(super) const SPLIT_SIZE: usize = 1 << LOG_SPLIT_SIZE;
+pub(super) const N_ID_AND_MULT_COLUMNS_PER_CHUNK: usize = 2;
+pub(super) const N_TRACE_COLUMNS: usize =
+    N_ADDR_COLUMNS + SPLIT_SIZE * N_ID_AND_MULT_COLUMNS_PER_CHUNK;
+
 pub type Component = FrameworkComponent<Eval>;
 
-// TODO(ShaharS): Break to repititions in order to batch the logup.
 #[derive(Clone)]
 pub struct Eval {
-    pub log_n_rows: u32,
+    // The log size of the component after split.
+    pub log_size: u32,
     pub lookup_elements: relations::MemoryAddressToId,
 }
 impl Eval {
     // TODO(ShaharS): use Seq column for address, and also use repititions.
     pub const fn n_columns(&self) -> usize {
-        N_ADDR_TO_ID_COLUMNS
+        N_TRACE_COLUMNS
     }
 
     pub fn new(claim: Claim, lookup_elements: relations::MemoryAddressToId) -> Self {
         Self {
-            log_n_rows: claim.log_size,
+            log_size: claim.log_size,
             lookup_elements,
         }
     }
 }
 
 impl FrameworkEval for Eval {
     fn log_size(&self) -> u32 {
-        self.log_n_rows
+        self.log_size
     }
 
     fn max_constraint_log_degree_bound(&self) -> u32 {
         self.log_size() + 1
     }
 
     fn evaluate<E: EvalAtRow>(&self, mut eval: E) -> E {
-        let address_and_id: [E::F; 2] = std::array::from_fn(|_| eval.next_trace_mask());
-        let multiplicity = eval.next_trace_mask();
-        eval.add_to_relation(&[RelationEntry::new(
-            &self.lookup_elements,
-            E::EF::from(-multiplicity),
-            &address_and_id,
-        )]);
+        let address = eval.next_trace_mask();
+        for i in 0..SPLIT_SIZE {
+            let id = eval.next_trace_mask();
+            let multiplicity = eval.next_trace_mask();
+            let address = address.clone() + E::F::from(M31((i * (1 << self.log_size())) as u32));
+            eval.add_to_relation(&[RelationEntry::new(
+                &self.lookup_elements,
+                E::EF::from(-multiplicity),
+                &[address, id],
+            )]);
+        }
 
         eval.finalize_logup();
         eval
@@ -62,8 +79,8 @@ pub struct Claim {
 impl Claim {
     pub fn log_sizes(&self) -> TreeVec<Vec<u32>> {
         let preprocessed_log_sizes = vec![self.log_size];
-        let trace_log_sizes = vec![self.log_size; N_ADDR_TO_ID_COLUMNS];
-        let interaction_log_sizes = vec![self.log_size; SECURE_EXTENSION_DEGREE];
+        let trace_log_sizes = vec![self.log_size; N_TRACE_COLUMNS];
+        let interaction_log_sizes = vec![self.log_size; SECURE_EXTENSION_DEGREE * SPLIT_SIZE];
         TreeVec::new(vec![
             preprocessed_log_sizes,
             trace_log_sizes,

stwo_cairo_prover/crates/prover/src/components/memory/memory_address_to_id/prover.rs

@@ -1,9 +1,10 @@
-use itertools::Itertools;
+use std::iter::zip;
+use std::simd::Simd;
+
+use itertools::{izip, Itertools};
 use stwo_prover::constraint_framework::logup::LogupTraceGenerator;
 use stwo_prover::constraint_framework::Relation;
-use stwo_prover::core::backend::simd::column::BaseColumn;
 use stwo_prover::core::backend::simd::m31::{PackedBaseField, PackedM31, LOG_N_LANES, N_LANES};
-use stwo_prover::core::backend::simd::qm31::PackedSecureField;
 use stwo_prover::core::backend::simd::SimdBackend;
 use stwo_prover::core::backend::{Col, Column};
 use stwo_prover::core::fields::m31::{BaseField, M31};
@@ -12,8 +13,10 @@ use stwo_prover::core::poly::circle::{CanonicCoset, CircleEvaluation};
 use stwo_prover::core::poly::BitReversedOrder;
 use stwo_prover::core::vcs::blake2_merkle::Blake2sMerkleChannel;
 
-use super::component::{Claim, InteractionClaim, N_ADDR_TO_ID_COLUMNS};
-use crate::components::memory::MEMORY_ADDRESS_BOUND;
+use super::component::{Claim, InteractionClaim, SPLIT_SIZE};
+use crate::components::memory_address_to_id::component::{
+    N_ID_AND_MULT_COLUMNS_PER_CHUNK, N_TRACE_COLUMNS,
+};
 use crate::input::mem::Memory;
 use crate::relations;
 
@@ -26,14 +29,11 @@ pub struct ClaimGenerator {
 }
 impl ClaimGenerator {
     pub fn new(mem: &Memory) -> Self {
-        let mut ids = (0..mem.address_to_id.len())
+        let ids = (0..mem.address_to_id.len())
             .map(|addr| mem.get_raw_id(addr as u32))
             .collect_vec();
-        let size = ids.len().next_power_of_two();
-        assert!(size <= MEMORY_ADDRESS_BOUND);
-        ids.resize(size, 0);
 
-        let multiplicities = vec![0; size];
+        let multiplicities = vec![0; ids.len()];
         Self {
             ids,
             multiplicities,
@@ -69,60 +69,62 @@ impl ClaimGenerator {
     }
 
     pub fn write_trace(
-        self,
+        mut self,
         tree_builder: &mut TreeBuilder<'_, '_, SimdBackend, Blake2sMerkleChannel>,
     ) -> (Claim, InteractionClaimGenerator) {
-        let size = self.ids.len();
-        let mut trace = (0..N_ADDR_TO_ID_COLUMNS)
-            .map(|_| Col::<SimdBackend, BaseField>::zeros(size))
-            .collect_vec();
+        let size = (self.ids.len() / SPLIT_SIZE).next_power_of_two();
+        let packed_size = size.div_ceil(N_LANES);
+        let mut trace: [_; N_TRACE_COLUMNS] =
+            std::array::from_fn(|_| Col::<SimdBackend, M31>::zeros(size));
 
-        let inc = PackedBaseField::from_array(std::array::from_fn(|i| {
-            BaseField::from_u32_unchecked((i) as u32)
-        }));
+        // Pad to a multiple of `N_LANES`.
+        let next_multiple_of_16 = ((self.ids.len() + 15) >> 4) << 4;
+        self.ids.resize(next_multiple_of_16, 0);
+        self.multiplicities.resize(next_multiple_of_16, 0);
 
         // TODO(Ohad): avoid copy.
-        let packed_ids = self
+        let id_it = self
             .ids
             .array_chunks::<N_LANES>()
-            .map(|chunk| {
-                PackedM31::from_array(std::array::from_fn(|i| M31::from_u32_unchecked(chunk[i])))
-            })
-            .collect_vec();
+            .map(|&chunk| unsafe { PackedM31::from_simd_unchecked(Simd::from_array(chunk)) });
+        let multiplicities_it = self
+            .multiplicities
+            .array_chunks::<N_LANES>()
+            .map(|&chunk| unsafe { PackedM31::from_simd_unchecked(Simd::from_array(chunk)) });
 
-        // Replace with seq.
-        for (i, id) in packed_ids.iter().enumerate() {
+        let inc =
+            PackedM31::from_array(std::array::from_fn(|i| M31::from_u32_unchecked((i) as u32)));
+        for i in 0..packed_size {
             trace[0].data[i] =
-                PackedM31::broadcast(BaseField::from_u32_unchecked((i * N_LANES) as u32)) + inc;
-            trace[1].data[i] = *id;
+                inc + PackedM31::broadcast(M31::from_u32_unchecked((i * N_LANES) as u32));
         }
 
-        // TODO(Ohad): avoid copy
-        trace[2] = BaseColumn::from_iter(
-            self.multiplicities
-                .clone()
-                .into_iter()
-                .map(BaseField::from_u32_unchecked),
-        );
+        // TODO(Ohad): Replace with seq.
+        for (i, (id, multiplicity)) in zip(id_it, multiplicities_it).enumerate() {
+            let chunk_idx = i / packed_size;
+            let i = i % packed_size;
+            trace[1 + chunk_idx * N_ID_AND_MULT_COLUMNS_PER_CHUNK].data[i] = id;
+            trace[2 + chunk_idx * N_ID_AND_MULT_COLUMNS_PER_CHUNK].data[i] = multiplicity;
+        }
 
         // Lookup data.
         let addresses = trace[0].data.clone();
-        let ids = trace[1].data.clone();
-        let multiplicities = trace[2].data.clone();
+        let ids: [_; SPLIT_SIZE] =
+            std::array::from_fn(|i| trace[1 + i * N_ID_AND_MULT_COLUMNS_PER_CHUNK].data.clone());
+        let multiplicities: [_; SPLIT_SIZE] =
+            std::array::from_fn(|i| trace[2 + i * N_ID_AND_MULT_COLUMNS_PER_CHUNK].data.clone());
 
         // Commit on trace.
-        let log_address_bound = size.checked_ilog2().unwrap();
-        let domain = CanonicCoset::new(log_address_bound).circle_domain();
+        let log_size = size.checked_ilog2().unwrap();
+        let domain = CanonicCoset::new(log_size).circle_domain();
         let trace = trace
             .into_iter()
             .map(|eval| CircleEvaluation::<SimdBackend, _, BitReversedOrder>::new(domain, eval))
             .collect_vec();
         tree_builder.extend_evals(trace);
 
         (
-            Claim {
-                log_size: log_address_bound,
-            },
+            Claim { log_size },
             InteractionClaimGenerator {
                 addresses,
                 ids,
@@ -134,34 +136,30 @@ impl ClaimGenerator {
 
 pub struct InteractionClaimGenerator {
     pub addresses: Vec<PackedM31>,
-    pub ids: Vec<PackedM31>,
-    pub multiplicities: Vec<PackedM31>,
+    pub ids: [Vec<PackedM31>; SPLIT_SIZE],
+    pub multiplicities: [Vec<PackedM31>; SPLIT_SIZE],
 }
 impl InteractionClaimGenerator {
-    pub fn with_capacity(capacity: usize) -> Self {
-        Self {
-            addresses: Vec::with_capacity(capacity),
-            ids: Vec::with_capacity(capacity),
-            multiplicities: Vec::with_capacity(capacity),
-        }
-    }
-
     pub fn write_interaction_trace(
         self,
         tree_builder: &mut TreeBuilder<'_, '_, SimdBackend, Blake2sMerkleChannel>,
         lookup_elements: &relations::MemoryAddressToId,
     ) -> InteractionClaim {
-        let log_size = self.addresses.len().ilog2() + LOG_N_LANES;
+        let packed_size = self.addresses.len();
+        let log_size = packed_size.ilog2() + LOG_N_LANES;
         let mut logup_gen = LogupTraceGenerator::new(log_size);
 
-        let mut col_gen = logup_gen.new_col();
-        for vec_row in 0..1 << (log_size - LOG_N_LANES) {
-            let addr = self.addresses[vec_row];
-            let id = self.ids[vec_row];
-            let denom: PackedSecureField = lookup_elements.combine(&[addr, id]);
-            col_gen.write_frac(vec_row, (-self.multiplicities[vec_row]).into(), denom);
+        for (i, (ids, multiplicities)) in izip!(&self.ids, &self.multiplicities).enumerate() {
+            let mut col_gen = logup_gen.new_col();
+            for (vec_row, (&addr, &id, &mult)) in
+                izip!(&self.addresses, ids, multiplicities).enumerate()
+            {
+                let addr = addr + PackedM31::broadcast(M31((i * (1 << log_size)) as u32));
+                let denom = lookup_elements.combine(&[addr, id]);
+                col_gen.write_frac(vec_row, (-mult).into(), denom);
+            }
+            col_gen.finalize_col();
         }
-        col_gen.finalize_col();
 
         let (trace, claimed_sum) = logup_gen.finalize_last();
         tree_builder.extend_evals(trace);