feat: avm support for public input columns (#5700)

Adds support for public input columns as outlined in the following
hackmd: https://hackmd.io/8kkJo4RkRTG6mpwL8fOf3w?both

barretenberg/cpp/pil/spike/README.md

@@ -0,0 +1,3 @@
+## Spike machine
+
+A spike machine for testing new PIL functionality

barretenberg/cpp/pil/spike/spike.pil

@@ -0,0 +1,8 @@
+
+namespace Spike(16);
+
+pol constant first = [1] + [0]*;
+pol commit x;
+pol public kernel_inputs;
+
+x - first = 0;

barretenberg/cpp/src/barretenberg/relations/generated/spike/declare_views.hpp

@@ -0,0 +1,7 @@
+
+#define Spike_DECLARE_VIEWS(index)                                                                                     \
+    using Accumulator = typename std::tuple_element<index, ContainerOverSubrelations>::type;                           \
+    using View = typename Accumulator::View;                                                                           \
+    [[maybe_unused]] auto Spike_first = View(new_term.Spike_first);                                                    \
+    [[maybe_unused]] auto Spike_kernel_inputs = View(new_term.Spike_kernel_inputs);                                    \
+    [[maybe_unused]] auto Spike_x = View(new_term.Spike_x);

barretenberg/cpp/src/barretenberg/relations/generated/spike/spike.hpp

@@ -0,0 +1,48 @@
+
+#pragma once
+#include "../../relation_parameters.hpp"
+#include "../../relation_types.hpp"
+#include "./declare_views.hpp"
+
+namespace bb::Spike_vm {
+
+template <typename FF> struct SpikeRow {
+    FF Spike_first{};
+    FF Spike_x{};
+};
+
+inline std::string get_relation_label_spike(int index)
+{
+    switch (index) {}
+    return std::to_string(index);
+}
+
+template <typename FF_> class spikeImpl {
+  public:
+    using FF = FF_;
+
+    static constexpr std::array<size_t, 1> SUBRELATION_PARTIAL_LENGTHS{
+        2,
+    };
+
+    template <typename ContainerOverSubrelations, typename AllEntities>
+    void static accumulate(ContainerOverSubrelations& evals,
+                           const AllEntities& new_term,
+                           [[maybe_unused]] const RelationParameters<FF>&,
+                           [[maybe_unused]] const FF& scaling_factor)
+    {
+
+        // Contribution 0
+        {
+            Spike_DECLARE_VIEWS(0);
+
+            auto tmp = (Spike_x - Spike_first);
+            tmp *= scaling_factor;
+            std::get<0>(evals) += tmp;
+        }
+    }
+};
+
+template <typename FF> using spike = Relation<spikeImpl<FF>>;
+
+} // namespace bb::Spike_vm

barretenberg/cpp/src/barretenberg/vm/generated/avm_flavor.hpp

@@ -2026,6 +2026,14 @@ class AvmFlavor {
      */
     template <size_t LENGTH> using ProverUnivariates = AllEntities<bb::Univariate<FF, LENGTH>>;
 
+    /**
+     * @brief A container for univariates used during Protogalaxy folding and sumcheck with some of the computation
+     * optmistically ignored
+     * @details During folding and sumcheck, the prover evaluates the relations on these univariates.
+     */
+    template <size_t LENGTH, size_t SKIP_COUNT>
+    using OptimisedProverUnivariates = AllEntities<bb::Univariate<FF, LENGTH, 0, SKIP_COUNT>>;
+
     /**
      * @brief A container for univariates produced during the hot loop in sumcheck.
      */

barretenberg/cpp/src/barretenberg/vm/generated/avm_verifier.cpp

@@ -3,9 +3,11 @@
 #include "./avm_verifier.hpp"
 #include "barretenberg/commitment_schemes/zeromorph/zeromorph.hpp"
 #include "barretenberg/numeric/bitop/get_msb.hpp"
+#include "barretenberg/polynomials/polynomial.hpp"
 #include "barretenberg/transcript/transcript.hpp"
 
 namespace bb {
+
 AvmVerifier::AvmVerifier(std::shared_ptr<Flavor::VerificationKey> verifier_key)
     : key(verifier_key)
 {}

barretenberg/cpp/src/barretenberg/vm/generated/spike_circuit_builder.hpp

@@ -0,0 +1,110 @@
+
+
+// AUTOGENERATED FILE
+#pragma once
+
+#include "barretenberg/common/constexpr_utils.hpp"
+#include "barretenberg/common/throw_or_abort.hpp"
+#include "barretenberg/ecc/curves/bn254/fr.hpp"
+#include "barretenberg/honk/proof_system/logderivative_library.hpp"
+#include "barretenberg/relations/generic_lookup/generic_lookup_relation.hpp"
+#include "barretenberg/relations/generic_permutation/generic_permutation_relation.hpp"
+#include "barretenberg/stdlib_circuit_builders/circuit_builder_base.hpp"
+
+#include "barretenberg/relations/generated/spike/spike.hpp"
+#include "barretenberg/vm/generated/spike_flavor.hpp"
+
+namespace bb {
+
+template <typename FF> struct SpikeFullRow {
+    FF Spike_first{};
+    FF Spike_kernel_inputs{};
+    FF Spike_x{};
+};
+
+class SpikeCircuitBuilder {
+  public:
+    using Flavor = bb::SpikeFlavor;
+    using FF = Flavor::FF;
+    using Row = SpikeFullRow<FF>;
+
+    // TODO: template
+    using Polynomial = Flavor::Polynomial;
+    using ProverPolynomials = Flavor::ProverPolynomials;
+
+    static constexpr size_t num_fixed_columns = 3;
+    static constexpr size_t num_polys = 3;
+    std::vector<Row> rows;
+
+    void set_trace(std::vector<Row>&& trace) { rows = std::move(trace); }
+
+    ProverPolynomials compute_polynomials()
+    {
+        const auto num_rows = get_circuit_subgroup_size();
+        ProverPolynomials polys;
+
+        // Allocate mem for each column
+        for (auto& poly : polys.get_all()) {
+            poly = Polynomial(num_rows);
+        }
+
+        for (size_t i = 0; i < rows.size(); i++) {
+            polys.Spike_first[i] = rows[i].Spike_first;
+            polys.Spike_kernel_inputs[i] = rows[i].Spike_kernel_inputs;
+            polys.Spike_x[i] = rows[i].Spike_x;
+        }
+
+        return polys;
+    }
+
+    [[maybe_unused]] bool check_circuit()
+    {
+
+        auto polys = compute_polynomials();
+        const size_t num_rows = polys.get_polynomial_size();
+
+        const auto evaluate_relation = [&]<typename Relation>(const std::string& relation_name,
+                                                              std::string (*debug_label)(int)) {
+            typename Relation::SumcheckArrayOfValuesOverSubrelations result;
+            for (auto& r : result) {
+                r = 0;
+            }
+            constexpr size_t NUM_SUBRELATIONS = result.size();
+
+            for (size_t i = 0; i < num_rows; ++i) {
+                Relation::accumulate(result, polys.get_row(i), {}, 1);
+
+                bool x = true;
+                for (size_t j = 0; j < NUM_SUBRELATIONS; ++j) {
+                    if (result[j] != 0) {
+                        std::string row_name = debug_label(static_cast<int>(j));
+                        throw_or_abort(
+                            format("Relation ", relation_name, ", subrelation index ", row_name, " failed at row ", i));
+                        x = false;
+                    }
+                }
+                if (!x) {
+                    return false;
+                }
+            }
+            return true;
+        };
+
+        if (!evaluate_relation.template operator()<Spike_vm::spike<FF>>("spike", Spike_vm::get_relation_label_spike)) {
+            return false;
+        }
+
+        return true;
+    }
+
+    [[nodiscard]] size_t get_num_gates() const { return rows.size(); }
+
+    [[nodiscard]] size_t get_circuit_subgroup_size() const
+    {
+        const size_t num_rows = get_num_gates();
+        const auto num_rows_log2 = static_cast<size_t>(numeric::get_msb64(num_rows));
+        size_t num_rows_pow2 = 1UL << (num_rows_log2 + (1UL << num_rows_log2 == num_rows ? 0 : 1));
+        return num_rows_pow2;
+    }
+};
+} // namespace bb

barretenberg/cpp/src/barretenberg/vm/generated/spike_composer.cpp

@@ -0,0 +1,86 @@
+
+
+#include "./spike_composer.hpp"
+#include "barretenberg/plonk_honk_shared/composer/composer_lib.hpp"
+#include "barretenberg/plonk_honk_shared/composer/permutation_lib.hpp"
+#include "barretenberg/vm/generated/spike_circuit_builder.hpp"
+#include "barretenberg/vm/generated/spike_verifier.hpp"
+
+namespace bb {
+
+using Flavor = SpikeFlavor;
+void SpikeComposer::compute_witness(CircuitConstructor& circuit)
+{
+    if (computed_witness) {
+        return;
+    }
+
+    auto polynomials = circuit.compute_polynomials();
+
+    for (auto [key_poly, prover_poly] : zip_view(proving_key->get_all(), polynomials.get_unshifted())) {
+        ASSERT(flavor_get_label(*proving_key, key_poly) == flavor_get_label(polynomials, prover_poly));
+        key_poly = prover_poly;
+    }
+
+    computed_witness = true;
+}
+
+SpikeProver SpikeComposer::create_prover(CircuitConstructor& circuit_constructor)
+{
+    compute_proving_key(circuit_constructor);
+    compute_witness(circuit_constructor);
+    compute_commitment_key(circuit_constructor.get_circuit_subgroup_size());
+
+    SpikeProver output_state(proving_key, proving_key->commitment_key);
+
+    return output_state;
+}
+
+SpikeVerifier SpikeComposer::create_verifier(CircuitConstructor& circuit_constructor)
+{
+    auto verification_key = compute_verification_key(circuit_constructor);
+
+    SpikeVerifier output_state(verification_key);
+
+    auto pcs_verification_key = std::make_unique<VerifierCommitmentKey>();
+
+    output_state.pcs_verification_key = std::move(pcs_verification_key);
+
+    return output_state;
+}
+
+std::shared_ptr<Flavor::ProvingKey> SpikeComposer::compute_proving_key(CircuitConstructor& circuit_constructor)
+{
+    if (proving_key) {
+        return proving_key;
+    }
+
+    // Initialize proving_key
+    {
+        const size_t subgroup_size = circuit_constructor.get_circuit_subgroup_size();
+        proving_key = std::make_shared<Flavor::ProvingKey>(subgroup_size, 0);
+    }
+
+    proving_key->contains_recursive_proof = false;
+
+    return proving_key;
+}
+
+std::shared_ptr<Flavor::VerificationKey> SpikeComposer::compute_verification_key(
+    CircuitConstructor& circuit_constructor)
+{
+    if (verification_key) {
+        return verification_key;
+    }
+
+    if (!proving_key) {
+        compute_proving_key(circuit_constructor);
+    }
+
+    verification_key =
+        std::make_shared<Flavor::VerificationKey>(proving_key->circuit_size, proving_key->num_public_inputs);
+
+    return verification_key;
+}
+
+} // namespace bb

barretenberg/cpp/src/barretenberg/vm/generated/spike_composer.hpp

@@ -0,0 +1,69 @@
+
+
+#pragma once
+
+#include "barretenberg/plonk_honk_shared/composer/composer_lib.hpp"
+#include "barretenberg/srs/global_crs.hpp"
+#include "barretenberg/vm/generated/spike_circuit_builder.hpp"
+#include "barretenberg/vm/generated/spike_prover.hpp"
+#include "barretenberg/vm/generated/spike_verifier.hpp"
+
+namespace bb {
+class SpikeComposer {
+  public:
+    using Flavor = SpikeFlavor;
+    using CircuitConstructor = SpikeCircuitBuilder;
+    using ProvingKey = Flavor::ProvingKey;
+    using VerificationKey = Flavor::VerificationKey;
+    using PCS = Flavor::PCS;
+    using CommitmentKey = Flavor::CommitmentKey;
+    using VerifierCommitmentKey = Flavor::VerifierCommitmentKey;
+
+    // TODO: which of these will we really need
+    static constexpr std::string_view NAME_STRING = "Spike";
+    static constexpr size_t NUM_RESERVED_GATES = 0;
+    static constexpr size_t NUM_WIRES = Flavor::NUM_WIRES;
+
+    std::shared_ptr<ProvingKey> proving_key;
+    std::shared_ptr<VerificationKey> verification_key;
+
+    // The crs_factory holds the path to the srs and exposes methods to extract the srs elements
+    std::shared_ptr<bb::srs::factories::CrsFactory<Flavor::Curve>> crs_factory_;
+
+    // The commitment key is passed to the prover but also used herein to compute the verfication key commitments
+    std::shared_ptr<CommitmentKey> commitment_key;
+
+    std::vector<uint32_t> recursive_proof_public_input_indices;
+    bool contains_recursive_proof = false;
+    bool computed_witness = false;
+
+    SpikeComposer() { crs_factory_ = bb::srs::get_bn254_crs_factory(); }
+
+    SpikeComposer(std::shared_ptr<ProvingKey> p_key, std::shared_ptr<VerificationKey> v_key)
+        : proving_key(std::move(p_key))
+        , verification_key(std::move(v_key))
+    {}
+
+    SpikeComposer(SpikeComposer&& other) noexcept = default;
+    SpikeComposer(SpikeComposer const& other) noexcept = default;
+    SpikeComposer& operator=(SpikeComposer&& other) noexcept = default;
+    SpikeComposer& operator=(SpikeComposer const& other) noexcept = default;
+    ~SpikeComposer() = default;
+
+    std::shared_ptr<ProvingKey> compute_proving_key(CircuitConstructor& circuit_constructor);
+    std::shared_ptr<VerificationKey> compute_verification_key(CircuitConstructor& circuit_constructor);
+
+    void compute_witness(CircuitConstructor& circuit_constructor);
+
+    SpikeProver create_prover(CircuitConstructor& circuit_constructor);
+    SpikeVerifier create_verifier(CircuitConstructor& circuit_constructor);
+
+    void add_table_column_selector_poly_to_proving_key(bb::polynomial& small, const std::string& tag);
+
+    void compute_commitment_key(size_t circuit_size)
+    {
+        proving_key->commitment_key = std::make_shared<CommitmentKey>(circuit_size);
+    };
+};
+
+} // namespace bb