fix!: Tx overhead and private emission L2 gas based on simulation time (#20648)

This PR:
- Splits AVM_MAX_PROCESSABLE_GAS (6M) from MAX_PROCESSABLE_GAS
(6M+PUBLIC_TX_OVERHEAD)
 - Splits Public tx overhead and private tx overhead
 - Plugs in numbers from simulation metrics to tx overheads
 - Plugs in numbers from simulation metrics to side effects
- TODO: Figure out contract class logs: we are having trouble measuring
them.

Author: AztecBot

barretenberg/cpp/src/barretenberg/avm_fuzzer/fuzz_lib/constants.hpp

@@ -32,7 +32,7 @@ const std::vector<ScopedL2ToL1Message> REVERTIBLE_ACCUMULATED_DATA_L2_TO_L1_MESS
 const std::vector<PublicCallRequestWithCalldata> SETUP_ENQUEUED_CALLS = {};
 const FF MSG_SENDER = 100;
 const std::optional<PublicCallRequestWithCalldata> TEARDOWN_ENQUEUED_CALLS = std::nullopt;
-const Gas GAS_USED_BY_PRIVATE = Gas{ .l2_gas = 0, .da_gas = 0 };
+const Gas GAS_USED_BY_PRIVATE = Gas{ .l2_gas = PUBLIC_TX_L2_GAS_OVERHEAD, .da_gas = TX_DA_GAS_OVERHEAD };
 const AztecAddress FEE_PAYER = AztecAddress{ 0 };
 const FF CONTRACT_ADDRESS = 42;
 const FF TRANSACTION_FEE = 0;

barretenberg/cpp/src/barretenberg/avm_fuzzer/mutations/tx_data.cpp

@@ -112,7 +112,7 @@ void mutate_tx(Tx& tx, std::vector<AztecAddress>& contract_addresses, std::mt199
     case TxMutationOptions::GasUsedByPrivate:
         // Mutate gas_used_by_private
         fuzz_info("Mutating gas used by private");
-        mutate_gas(tx.gas_used_by_private, rng, tx.gas_settings.gas_limits);
+        mutate_gas(tx.gas_used_by_private, rng, GAS_USED_BY_PRIVATE, tx.gas_settings.gas_limits);
         break;
     case TxMutationOptions::FeePayer:
         // Mutate fee_payer

barretenberg/cpp/src/barretenberg/avm_fuzzer/mutations/tx_types/gas.cpp

@@ -28,26 +28,26 @@ uint128_t generate_u128(std::mt19937_64& rng, uint128_t min = 0, uint128_t max =
 
 namespace bb::avm2::fuzzer {
 
-Gas generate_gas(std::mt19937_64& rng)
+Gas generate_gas(std::mt19937_64& rng, const Gas& min, const Gas& max)
 {
-    uint32_t l2_gas = std::uniform_int_distribution<uint32_t>(MIN_GAS, AVM_MAX_PROCESSABLE_L2_GAS)(rng);
-    uint32_t da_gas = std::uniform_int_distribution<uint32_t>(MIN_GAS, AVM_MAX_PROCESSABLE_DA_GAS)(rng);
+    uint32_t l2_gas = std::uniform_int_distribution<uint32_t>(min.l2_gas, max.l2_gas)(rng);
+    uint32_t da_gas = std::uniform_int_distribution<uint32_t>(min.da_gas, max.da_gas)(rng);
 
     return Gas{ l2_gas, da_gas };
 }
 
-void mutate_gas(Gas& gas, std::mt19937_64& rng, const Gas& max)
+void mutate_gas(Gas& gas, std::mt19937_64& rng, const Gas& min, const Gas& max)
 {
     auto choice = std::uniform_int_distribution<uint8_t>(0, 1)(rng);
 
     switch (choice) {
     case 0:
         // Mutate l2_gas
-        gas.l2_gas = std::uniform_int_distribution<uint32_t>(MIN_GAS, max.l2_gas)(rng);
+        gas.l2_gas = std::uniform_int_distribution<uint32_t>(min.l2_gas, max.l2_gas)(rng);
         break;
     case 1:
         // Mutate da_gas
-        gas.da_gas = std::uniform_int_distribution<uint32_t>(MIN_GAS, max.da_gas)(rng);
+        gas.da_gas = std::uniform_int_distribution<uint32_t>(min.da_gas, max.da_gas)(rng);
         break;
     }
 }

barretenberg/cpp/src/barretenberg/avm_fuzzer/mutations/tx_types/gas.hpp

@@ -15,12 +15,13 @@ constexpr uint128_t MIN_FEE = 1;
 constexpr uint128_t MAX_FEE = 1000;
 //
 // Gas bounds for mutation
-constexpr uint32_t MIN_GAS = 0;
-constexpr uint32_t AVM_MAX_PROCESSABLE_DA_GAS = (MAX_NOTE_HASHES_PER_TX * AVM_EMITNOTEHASH_BASE_DA_GAS) +
-                                                (MAX_NULLIFIERS_PER_TX * AVM_EMITNULLIFIER_BASE_DA_GAS) +
-                                                (MAX_L2_TO_L1_MSGS_PER_TX * AVM_SENDL2TOL1MSG_BASE_DA_GAS) +
-                                                (MAX_TOTAL_PUBLIC_DATA_UPDATE_REQUESTS_PER_TX * AVM_SSTORE_DYN_DA_GAS) +
-                                                (PUBLIC_LOGS_LENGTH * AVM_EMITPUBLICLOG_BASE_DA_GAS);
+constexpr uint32_t MAX_PROCESSABLE_DA_GAS = TX_DA_GAS_OVERHEAD +
+                                            (MAX_NOTE_HASHES_PER_TX * AVM_EMITNOTEHASH_BASE_DA_GAS) +
+                                            (MAX_NULLIFIERS_PER_TX * AVM_EMITNULLIFIER_BASE_DA_GAS) +
+                                            (MAX_L2_TO_L1_MSGS_PER_TX * AVM_SENDL2TOL1MSG_BASE_DA_GAS) +
+                                            (MAX_TOTAL_PUBLIC_DATA_UPDATE_REQUESTS_PER_TX * AVM_SSTORE_DYN_DA_GAS) +
+                                            (PUBLIC_LOGS_LENGTH * AVM_EMITPUBLICLOG_BASE_DA_GAS);
+constexpr Gas MAX_GAS_LIMIT = Gas{ .l2_gas = MAX_PROCESSABLE_L2_GAS, .da_gas = MAX_PROCESSABLE_DA_GAS };
 
 enum class GasSettingsMutationOptions : uint8_t {
     GasLimits,
@@ -38,10 +39,8 @@ constexpr GasSettingsMutationConfig GAS_SETTINGS_MUTATION_CONFIGURATION = GasSet
     { GasSettingsMutationOptions::MaxPriorityFeesPerGas, 5 },
 });
 
-Gas generate_gas(std::mt19937_64& rng);
-void mutate_gas(Gas& gas,
-                std::mt19937_64& rng,
-                const Gas& max = Gas{ AVM_MAX_PROCESSABLE_L2_GAS, AVM_MAX_PROCESSABLE_DA_GAS });
+Gas generate_gas(std::mt19937_64& rng, const Gas& min = {}, const Gas& max = MAX_GAS_LIMIT);
+void mutate_gas(Gas& gas, std::mt19937_64& rng, const Gas& min = {}, const Gas& max = MAX_GAS_LIMIT);
 
 GasSettings generate_gas_settings(std::mt19937_64& rng);
 void mutate_gas_settings(GasSettings& data, std::mt19937_64& rng);

barretenberg/cpp/src/barretenberg/vm2/common/aztec_constants.hpp

@@ -179,7 +179,10 @@
 #define AVM_PUBLIC_INPUTS_COLUMNS_COMBINED_LENGTH 18740
 #define AVM_V2_PROOF_LENGTH_IN_FIELDS_PADDED 16400
 #define AVM_V2_VERIFICATION_KEY_LENGTH_IN_FIELDS_PADDED 1000
+#define TX_DA_GAS_OVERHEAD 96
+#define PUBLIC_TX_L2_GAS_OVERHEAD 540000
 #define AVM_MAX_PROCESSABLE_L2_GAS 6000000
+#define MAX_PROCESSABLE_L2_GAS 6540000
 #define AVM_PC_SIZE_IN_BITS 32
 #define AVM_MAX_OPERANDS 7
 #define AVM_MAX_REGISTERS 6
@@ -221,7 +224,7 @@
 #define AVM_L1TOL2MSGEXISTS_BASE_L2_GAS 540
 #define AVM_GETCONTRACTINSTANCE_BASE_L2_GAS 6108
 #define AVM_EMITPUBLICLOG_BASE_L2_GAS 15
-#define AVM_SENDL2TOL1MSG_BASE_L2_GAS 478
+#define AVM_SENDL2TOL1MSG_BASE_L2_GAS 5239
 #define AVM_CALL_BASE_L2_GAS 9936
 #define AVM_STATICCALL_BASE_L2_GAS 9936
 #define AVM_RETURN_BASE_L2_GAS 9

barretenberg/cpp/src/barretenberg/vm2/constraining/avm_fixed_vk.hpp

@@ -17,7 +17,7 @@ class AvmHardCodedVKAndHash {
     using FF = bb::curve::BN254::ScalarField;
 
     // Precomputed VK hash (hash of all commitments below).
-    static FF vk_hash() { return FF(uint256_t("0x02296b934ced1a5cdacae120d2032d88a119bdb0738d4c4f3ada4f5a831a5153")); }
+    static FF vk_hash() { return FF(uint256_t("0x18952f5711d5f7a6e29c980f1077eecd2ec45e80ba0ae78d5a4ae08e50428cab")); }
 
     static constexpr std::array<Commitment, NUM_PRECOMPUTED_ENTITIES> get_all()
     {
@@ -71,9 +71,9 @@ class AvmHardCodedVKAndHash {
                 uint256_t(
                     "0x090dda25e7d64ab5cabe09fd80fbb731af2a98de7a608157dc10394b4fc022a4")), // precomputed_exec_opcode_dynamic_l2_gas
             Commitment(
-                uint256_t("0x2216a1693dcb1cc83f57ea8058f681d71bdf0e6cfc839502cf16fb0a88a5f673"),
+                uint256_t("0x26086b5fb31a24f236f0441d5b922b94ca141e861b9cc640184681c518cd68d3"),
                 uint256_t(
-                    "0x255e6760ed9adda61aca7d0b7d4bb28bb62e3cca6e860009461a9a1708184be2")), // precomputed_exec_opcode_opcode_gas
+                    "0x0bab134bb4e25ff33584c1094847e762ce6573054bae27715d0e4eb2b7278d80")), // precomputed_exec_opcode_opcode_gas
             Commitment(
                 uint256_t("0x296def9415d1c96b4d8ab91df5f59ad8522a726f98461b1ab5c4d4c5b22471a4"),
                 uint256_t(

barretenberg/cpp/src/barretenberg/vm2/testing/avm_inputs.testdata.bin

@@ -89,5 +89,11 @@ pub fn meter_gas_used(public_inputs: PrivateKernelCircuitPublicInputs, is_for_pu
 
     let metered_da_gas = metered_da_fields * DA_GAS_PER_FIELD;
 
-    Gas::tx_overhead() + Gas::new(metered_da_gas, metered_l2_gas) + teardown_gas
+    let overhead = if is_for_public {
+        Gas::public_tx_overhead()
+    } else {
+        Gas::private_tx_overhead()
+    };
+
+    overhead + Gas::new(metered_da_gas, metered_l2_gas) + teardown_gas
 }

barretenberg/cpp/src/barretenberg/vm2/testing/minimal_tx.testdata.bin

@@ -12,7 +12,7 @@ use types::{
 /// A minimum (private) tx initialized in the TestBuilder contains a protocol nullifier, which must exist in every tx.
 fn get_minimum_private_tx_gas_used() -> Gas {
     let nullifier_gas_used = Gas { da_gas: DA_GAS_PER_FIELD, l2_gas: L2_GAS_PER_NULLIFIER };
-    Gas::tx_overhead() + nullifier_gas_used
+    Gas::private_tx_overhead() + nullifier_gas_used
 }
 
 #[test]
@@ -100,7 +100,7 @@ fn full_side_effects() {
     let mut builder = TestBuilder::new();
 
     // Fill the tx with side effects and compute the expected gas used.
-    let mut expected_gas_used = Gas::tx_overhead();
+    let mut expected_gas_used = Gas::private_tx_overhead();
     // Note hashes.
     builder.previous_kernel.append_siloed_note_hashes(MAX_NOTE_HASHES_PER_TX);
     expected_gas_used += Gas {