feat: WIP first pass hint collecting dbs c++ sim

Author: MirandaWood

barretenberg/cpp/src/barretenberg/vm2/simulation/gadgets/concrete_dbs.cpp

@@ -7,7 +7,7 @@
 namespace bb::avm2::simulation {
 
 // Contracts DB starts.
-std::optional<ContractInstance> ContractDB::get_contract_instance(const AztecAddress& address) const
+std::optional<ContractInstance> ContractDB::get_contract_instance(const AztecAddress& address)
 {
     std::optional<ContractInstance> instance = raw_contract_db.get_contract_instance(address);
     // If we didn't get a contract instance, we don't prove anything.
@@ -26,7 +26,7 @@ std::optional<ContractInstance> ContractDB::get_contract_instance(const AztecAdd
     return instance;
 }
 
-std::optional<ContractClass> ContractDB::get_contract_class(const ContractClassId& class_id) const
+std::optional<ContractClass> ContractDB::get_contract_class(const ContractClassId& class_id)
 {
     std::optional<ContractClass> klass = raw_contract_db.get_contract_class(class_id);
     // If we didn't get a contract class, we don't prove anything.

barretenberg/cpp/src/barretenberg/vm2/simulation/gadgets/concrete_dbs.hpp

@@ -30,11 +30,11 @@ class ContractDB final : public ContractDBInterface {
     // Gets an instance from the DB and proves address derivation from the result.
     // This does NOT prove that the address is in the nullifier tree.
     // Silo the address and use the MerkleDB to prove that.
-    std::optional<ContractInstance> get_contract_instance(const AztecAddress& address) const override;
+    std::optional<ContractInstance> get_contract_instance(const AztecAddress& address) override;
     // Gets a class from the DB and proves class id derivation from the result.
     // This does NOT prove that the class id is in the nullifier tree.
     // Silo the class id and use the MerkleDB to prove that.
-    std::optional<ContractClass> get_contract_class(const ContractClassId& class_id) const override;
+    std::optional<ContractClass> get_contract_class(const ContractClassId& class_id) override;
 
   private:
     ContractDBInterface& raw_contract_db;

barretenberg/cpp/src/barretenberg/vm2/simulation/gadgets/update_check.cpp

@@ -11,7 +11,7 @@ namespace {
 
 using UnconstrainedPoseidon2 = crypto::Poseidon2<crypto::Poseidon2Bn254ScalarFieldParams>;
 
-FF unconstrained_read(const LowLevelMerkleDBInterface& merkle_db, const FF& leaf_slot)
+FF unconstrained_read(LowLevelMerkleDBInterface& merkle_db, const FF& leaf_slot)
 {
     auto [present, index] = merkle_db.get_low_indexed_leaf(world_state::MerkleTreeId::PUBLIC_DATA_TREE, leaf_slot);
     auto preimage = merkle_db.get_leaf_preimage_public_data_tree(index);

barretenberg/cpp/src/barretenberg/vm2/simulation/interfaces/db.hpp

@@ -18,8 +18,8 @@ class ContractDBInterface {
   public:
     virtual ~ContractDBInterface() = default;
 
-    virtual std::optional<ContractInstance> get_contract_instance(const AztecAddress& address) const = 0;
-    virtual std::optional<ContractClass> get_contract_class(const ContractClassId& class_id) const = 0;
+    virtual std::optional<ContractInstance> get_contract_instance(const AztecAddress& address) = 0;
+    virtual std::optional<ContractClass> get_contract_class(const ContractClassId& class_id) = 0;
 };
 
 // Aliases.
@@ -45,13 +45,13 @@ class LowLevelMerkleDBInterface {
 
     virtual TreeSnapshots get_tree_roots() const = 0;
 
-    virtual SiblingPath get_sibling_path(MerkleTreeId tree_id, index_t leaf_index) const = 0;
-    virtual GetLowIndexedLeafResponse get_low_indexed_leaf(MerkleTreeId tree_id, const FF& value) const = 0;
+    virtual SiblingPath get_sibling_path(MerkleTreeId tree_id, index_t leaf_index) = 0;
+    virtual GetLowIndexedLeafResponse get_low_indexed_leaf(MerkleTreeId tree_id, const FF& value) = 0;
     // Returns the value if it exists, 0 otherwise.
-    virtual FF get_leaf_value(MerkleTreeId tree_id, index_t leaf_index) const = 0;
+    virtual FF get_leaf_value(MerkleTreeId tree_id, index_t leaf_index) = 0;
     // We don't template the preimage methods because templated methods cannot be virtual.
-    virtual IndexedLeaf<PublicDataLeafValue> get_leaf_preimage_public_data_tree(index_t leaf_index) const = 0;
-    virtual IndexedLeaf<NullifierLeafValue> get_leaf_preimage_nullifier_tree(index_t leaf_index) const = 0;
+    virtual IndexedLeaf<PublicDataLeafValue> get_leaf_preimage_public_data_tree(index_t leaf_index) = 0;
+    virtual IndexedLeaf<NullifierLeafValue> get_leaf_preimage_nullifier_tree(index_t leaf_index) = 0;
 
     virtual SequentialInsertionResult<PublicDataLeafValue> insert_indexed_leaves_public_data_tree(
         const PublicDataLeafValue& leaf_value) = 0;

barretenberg/cpp/src/barretenberg/vm2/simulation/lib/db_types.hpp

@@ -19,3 +19,18 @@ struct TreeCounters {
 };
 
 } // namespace bb::avm2::simulation
+
+// Specialization of std::hash for std::vector<FF> to be used as a key in unordered_flat_map.
+// Used in raw_data_dbs and hinting_dbs
+namespace std {
+template <> struct hash<std::vector<bb::avm2::FF>> {
+    size_t operator()(const std::vector<bb::avm2::FF>& vec) const
+    {
+        size_t seed = vec.size();
+        for (const auto& item : vec) {
+            seed ^= std::hash<bb::avm2::FF>{}(item) + 0x9e3779b9 + (seed << 6) + (seed >> 2);
+        }
+        return seed;
+    }
+};
+} // namespace std