feat: AVM inserts fee write on txs with public calls

barretenberg/cpp/src/barretenberg/vm/avm/trace/execution.cpp

@@ -26,6 +26,7 @@
 #include <cstdint>
 #include <cstdlib>
 #include <filesystem>
+#include <stdexcept>
 #include <string>
 #include <tuple>
 #include <unordered_map>
@@ -377,10 +378,16 @@ std::vector<Row> Execution::gen_trace(AvmPublicInputs const& public_inputs,
 
         if (!is_ok(phase_error) && phase == TxExecutionPhase::SETUP) {
             // Stop processing phases. Halt TX.
-            info("A revert during SETUP phase halts the entire TX");
+            info("A revert was encountered in the SETUP phase, killing the entire TX");
+            throw std::runtime_error("A revert was encountered in the SETUP phase, killing the entire TX");
             break;
         }
     }
+
+    if (apply_e2e_assertions) {
+        trace_builder.pay_fee();
+    }
+
     auto trace = trace_builder.finalize(apply_e2e_assertions);
 
     returndata = trace_builder.get_all_returndata();

barretenberg/cpp/src/barretenberg/vm/avm/trace/public_inputs.hpp

@@ -306,6 +306,7 @@ class AvmPublicInputs {
     TreeSnapshots start_tree_snapshots;
     Gas start_gas_used;
     GasSettings gas_settings;
+    FF fee_payer;
     std::array<PublicCallRequest, MAX_ENQUEUED_CALLS_PER_TX> public_setup_call_requests;
     std::array<PublicCallRequest, MAX_ENQUEUED_CALLS_PER_TX> public_app_logic_call_requests;
     PublicCallRequest public_teardown_call_request;
@@ -330,6 +331,7 @@ class AvmPublicInputs {
         read(it, public_inputs.start_tree_snapshots);
         read(it, public_inputs.start_gas_used);
         read(it, public_inputs.gas_settings);
+        read(it, public_inputs.fee_payer);
         read(it, public_inputs.public_setup_call_requests);
         read(it, public_inputs.public_app_logic_call_requests);
         read(it, public_inputs.public_teardown_call_request);

barretenberg/cpp/src/barretenberg/vm/avm/trace/trace.cpp

@@ -8,6 +8,7 @@
 #include <iostream>
 #include <limits>
 #include <set>
+#include <stdexcept>
 #include <string>
 #include <sys/types.h>
 #include <unordered_map>
@@ -32,6 +33,7 @@
 #include "barretenberg/vm/avm/trace/gadgets/cmp.hpp"
 #include "barretenberg/vm/avm/trace/gadgets/keccak.hpp"
 #include "barretenberg/vm/avm/trace/gadgets/merkle_tree.hpp"
+#include "barretenberg/vm/avm/trace/gadgets/poseidon2.hpp"
 #include "barretenberg/vm/avm/trace/gadgets/slice_trace.hpp"
 #include "barretenberg/vm/avm/trace/helper.hpp"
 #include "barretenberg/vm/avm/trace/opcode.hpp"
@@ -225,6 +227,63 @@ void AvmTraceBuilder::insert_private_state(const std::vector<FF>& siloed_nullifi
     }
 }
 
+void AvmTraceBuilder::pay_fee()
+{
+    auto clk = static_cast<uint32_t>(main_trace.size()) + 1;
+
+    auto tx_fee = (public_inputs.global_variables.gas_fees.fee_per_da_gas * public_inputs.end_gas_used.da_gas) +
+                  (public_inputs.global_variables.gas_fees.fee_per_l2_gas * public_inputs.end_gas_used.l2_gas);
+
+    if (public_inputs.fee_payer == 0) {
+        vinfo("No one is paying the fee of ", tx_fee);
+        return;
+    }
+
+    // ** Compute the storage slot **
+    // using the base slot of the balances map and the fee payer address (map key)
+    // TS equivalent:
+    // computeFeePayerBalanceStorageSlot(fee_payer);
+    std::vector<FF> slot_hash_inputs = { FEE_JUICE_BALANCES_SLOT, public_inputs.fee_payer };
+    const auto balance_slot = poseidon2_trace_builder.poseidon2_hash(slot_hash_inputs, clk, Poseidon2Caller::SILO);
+
+    // ** Read the balance before fee payment **
+    // TS equivalent:
+    // current_balance = readStorage(FEE_JUICE_ADDRESS, balance_slot);
+    PublicDataReadTreeHint read_hint = execution_hints.storage_read_hints.at(storage_read_counter++);
+    FF computed_tree_slot =
+        merkle_tree_trace_builder.compute_public_tree_leaf_slot(clk, FEE_JUICE_ADDRESS, balance_slot);
+    // Sanity check that the computed slot using the value read from slot_offset should match the read hint
+    ASSERT(computed_tree_slot == read_hint.leaf_preimage.slot);
+
+    // ** Write the updated balance after fee payment **
+    // TS equivalent:
+    // Check that the leaf is a member of the public data tree
+    bool is_member = merkle_tree_trace_builder.perform_storage_read(
+        clk, read_hint.leaf_preimage, read_hint.leaf_index, read_hint.sibling_path);
+    ASSERT(is_member);
+    FF current_balance = read_hint.leaf_preimage.value;
+
+    const auto updated_balance = current_balance - tx_fee;
+    if (current_balance < tx_fee) {
+        info("Not enough balance for fee payer to pay for transaction (got ", current_balance, " needs ", tx_fee);
+        throw std::runtime_error("Not enough balance for fee payer to pay for transaction");
+    }
+
+    // writeStorage(FEE_JUICE_ADDRESS, balance_slot, updated_balance);
+    PublicDataWriteTreeHint write_hint = execution_hints.storage_write_hints.at(storage_write_counter++);
+    ASSERT(write_hint.new_leaf_preimage.value == updated_balance);
+    merkle_tree_trace_builder.perform_storage_write(clk,
+                                                    write_hint.low_leaf_membership.leaf_preimage,
+                                                    write_hint.low_leaf_membership.leaf_index,
+                                                    write_hint.low_leaf_membership.sibling_path,
+                                                    write_hint.new_leaf_preimage.slot,
+                                                    write_hint.new_leaf_preimage.value,
+                                                    write_hint.insertion_path);
+
+    debug("pay fee side-effect cnt: ", side_effect_counter);
+    side_effect_counter++;
+}
+
 /**
  * @brief Loads a value from memory into a given intermediate register at a specified clock cycle.
  * Handles both direct and indirect memory access.
@@ -2528,6 +2587,9 @@ AvmError AvmTraceBuilder::op_sstore(uint8_t indirect, uint32_t src_offset, uint3
     auto clk = static_cast<uint32_t>(main_trace.size()) + 1;
 
     if (storage_write_counter >= MAX_PUBLIC_DATA_UPDATE_REQUESTS_PER_TX) {
+        // NOTE: the circuit constraint for this limit should only be applied
+        // for the storage writes performed by this opcode. An exception should before
+        // made for the fee juice storage write made after teardown.
         error = AvmError::SIDE_EFFECT_LIMIT_REACHED;
         auto row = Row{
             .main_clk = clk,

barretenberg/cpp/src/barretenberg/vm/avm/trace/trace.hpp

@@ -235,6 +235,7 @@ class AvmTraceBuilder {
     std::vector<uint8_t> get_bytecode(const FF contract_address, bool check_membership = false);
     std::unordered_set<FF> bytecode_membership_cache;
     void insert_private_state(const std::vector<FF>& siloed_nullifiers, const std::vector<FF>& siloed_note_hashes);
+    void pay_fee();
 
     // These are used for testing only.
     AvmTraceBuilder& set_range_check_required(bool required)

barretenberg/cpp/src/barretenberg/vm/aztec_constants.hpp

@@ -26,6 +26,7 @@
 #define MULTI_CALL_ENTRYPOINT_ADDRESS 4
 #define FEE_JUICE_ADDRESS 5
 #define ROUTER_ADDRESS 6
+#define FEE_JUICE_BALANCES_SLOT 1
 #define AZTEC_ADDRESS_LENGTH 1
 #define GAS_FEES_LENGTH 2
 #define GAS_LENGTH 2
@@ -45,8 +46,8 @@
 #define STATE_REFERENCE_LENGTH 8
 #define TOTAL_FEES_LENGTH 1
 #define PUBLIC_CIRCUIT_PUBLIC_INPUTS_LENGTH 867
-#define AVM_ACCUMULATED_DATA_LENGTH 318
-#define AVM_CIRCUIT_PUBLIC_INPUTS_LENGTH 1006
+#define AVM_ACCUMULATED_DATA_LENGTH 320
+#define AVM_CIRCUIT_PUBLIC_INPUTS_LENGTH 1008
 #define AVM_VERIFICATION_KEY_LENGTH_IN_FIELDS 86
 #define AVM_PROOF_LENGTH_IN_FIELDS 4155
 #define AVM_PUBLIC_COLUMN_MAX_SIZE 1024

l1-contracts/src/core/libraries/ConstantsGen.sol

@@ -138,6 +138,7 @@ library Constants {
   uint256 internal constant MULTI_CALL_ENTRYPOINT_ADDRESS = 4;
   uint256 internal constant FEE_JUICE_ADDRESS = 5;
   uint256 internal constant ROUTER_ADDRESS = 6;
+  uint256 internal constant FEE_JUICE_BALANCES_SLOT = 1;
   uint256 internal constant DEFAULT_NPK_M_X =
     582240093077765400562621227108555700500271598878376310175765873770292988861;
   uint256 internal constant DEFAULT_NPK_M_Y =
@@ -208,7 +209,7 @@ library Constants {
   uint256 internal constant SCOPED_READ_REQUEST_LEN = 3;
   uint256 internal constant PUBLIC_DATA_READ_LENGTH = 3;
   uint256 internal constant PRIVATE_VALIDATION_REQUESTS_LENGTH = 772;
-  uint256 internal constant COMBINED_ACCUMULATED_DATA_LENGTH = 900;
+  uint256 internal constant COMBINED_ACCUMULATED_DATA_LENGTH = 902;
   uint256 internal constant TX_CONSTANT_DATA_LENGTH = 35;
   uint256 internal constant COMBINED_CONSTANT_DATA_LENGTH = 44;
   uint256 internal constant PRIVATE_ACCUMULATED_DATA_LENGTH = 1412;
@@ -217,7 +218,7 @@ library Constants {
   uint256 internal constant PRIVATE_TO_AVM_ACCUMULATED_DATA_LENGTH = 160;
   uint256 internal constant NUM_PRIVATE_TO_AVM_ACCUMULATED_DATA_ARRAYS = 3;
   uint256 internal constant PRIVATE_TO_PUBLIC_KERNEL_CIRCUIT_PUBLIC_INPUTS_LENGTH = 1845;
-  uint256 internal constant KERNEL_CIRCUIT_PUBLIC_INPUTS_LENGTH = 956;
+  uint256 internal constant KERNEL_CIRCUIT_PUBLIC_INPUTS_LENGTH = 958;
   uint256 internal constant CONSTANT_ROLLUP_DATA_LENGTH = 13;
   uint256 internal constant BASE_OR_MERGE_PUBLIC_INPUTS_LENGTH = 31;
   uint256 internal constant BLOCK_ROOT_OR_BLOCK_MERGE_PUBLIC_INPUTS_LENGTH = 90;

noir-projects/noir-protocol-circuits/crates/rollup-lib/src/abis/base_or_merge_rollup_public_inputs.nr

@@ -12,23 +12,23 @@ pub(crate) global MERGE_ROLLUP_TYPE: u32 = 1;
 pub struct BaseOrMergeRollupPublicInputs {
     // rollup_type is either 0 (base) or 1 (merge)
     // TODO(Kev): Why is this a u32 instead of a u8/u16?
-    pub rollup_type: u32,
-    pub num_txs: u32,
-    pub constants: ConstantRollupData,
+    pub(crate) rollup_type: u32,
+    pub(crate) num_txs: u32,
+    pub(crate) constants: ConstantRollupData,
 
-    pub start: PartialStateReference,
-    pub end: PartialStateReference,
+    pub(crate) start: PartialStateReference,
+    pub(crate) end: PartialStateReference,
 
     // We hash public inputs to make them constant-sized (to then be unpacked on-chain)
     // U128 isn't safe if it's an input to the circuit (it won't automatically constrain the witness)
     // So we want to constrain it when casting these fields to U128
 
     // We hash public inputs to make them constant-sized (to then be unpacked on-chain)
-    pub txs_effects_hash: Field,
-    pub out_hash: Field,
+    pub(crate) txs_effects_hash: Field,
+    pub(crate) out_hash: Field,
 
-    pub accumulated_fees: Field,
-    pub accumulated_mana_used: Field,
+    pub(crate) accumulated_fees: Field,
+    pub(crate) accumulated_mana_used: Field,
 }
 
 impl Empty for BaseOrMergeRollupPublicInputs {