openvm_circuit/system/poseidon2/
trace.rs

1use std::borrow::BorrowMut;
2
3use openvm_circuit_primitives::{utils::next_power_of_two_or_zero, Chip};
4use openvm_cpu_backend::CpuBackend;
5use openvm_stark_backend::{
6    p3_air::BaseAir, p3_field::PrimeCharacteristicRing, p3_matrix::dense::RowMajorMatrix,
7    p3_maybe_rayon::prelude::*, prover::AirProvingContext, StarkProtocolConfig, Val,
8};
9
10use super::{columns::*, Poseidon2PeripheryBaseChip, PERIPHERY_POSEIDON2_WIDTH};
11use crate::arch::VmField;
12
13impl<RA, SC: StarkProtocolConfig, const SBOX_REGISTERS: usize> Chip<RA, CpuBackend<SC>>
14    for Poseidon2PeripheryBaseChip<Val<SC>, SBOX_REGISTERS>
15where
16    Val<SC>: VmField,
17{
18    /// Generates trace and clears internal records state.
19    fn generate_proving_ctx(&self, _: RA) -> AirProvingContext<CpuBackend<SC>> {
20        let width = Poseidon2PeripheryCols::<Val<SC>, SBOX_REGISTERS>::width();
21        if !self.nonempty.load(std::sync::atomic::Ordering::Relaxed) {
22            let trace = RowMajorMatrix::new(vec![], width);
23            return AirProvingContext::simple_no_pis(trace);
24        }
25        let height = next_power_of_two_or_zero(self.records.len());
26
27        let mut inputs = Vec::with_capacity(height);
28        let mut multiplicities = Vec::with_capacity(height);
29        #[cfg(feature = "parallel")]
30        let records_iter = self.records.par_iter();
31        #[cfg(not(feature = "parallel"))]
32        let records_iter = self.records.iter();
33        let (actual_inputs, actual_multiplicities): (Vec<_>, Vec<_>) = records_iter
34            .map(|r| {
35                let (input, mult) = r.pair();
36                (*input, mult.load(std::sync::atomic::Ordering::Relaxed))
37            })
38            .unzip();
39        inputs.extend(actual_inputs);
40        multiplicities.extend(actual_multiplicities);
41        inputs.resize(height, [Val::<SC>::ZERO; PERIPHERY_POSEIDON2_WIDTH]);
42        multiplicities.resize(height, 0);
43
44        // TODO: this would be more optimal if plonky3 made the generate_trace_row function public
45        let inner_trace = self.subchip.generate_trace(inputs);
46        let inner_width = self.subchip.air.width();
47
48        let mut values = Val::<SC>::zero_vec(height * width);
49        values
50            .par_chunks_mut(width)
51            .zip(inner_trace.values.par_chunks(inner_width))
52            .zip(multiplicities)
53            .for_each(|((row, inner_row), mult)| {
54                // WARNING: Poseidon2SubCols must be the first field in Poseidon2PeripheryCols
55                row[..inner_width].copy_from_slice(inner_row);
56                let cols: &mut Poseidon2PeripheryCols<Val<SC>, SBOX_REGISTERS> = row.borrow_mut();
57                cols.mult = Val::<SC>::from_u32(mult);
58            });
59        self.records.clear();
60        self.nonempty
61            .store(false, std::sync::atomic::Ordering::Relaxed);
62
63        let trace = RowMajorMatrix::new(values, width);
64        AirProvingContext::simple_no_pis(trace)
65    }
66}
openvm_circuit/system/poseidon2/trace.rs

openvm_circuit/system/poseidon2/
trace.rs
