Merge pull request #19 from OffchainLabs/add-precompiles-for-multi-constraint-pricer

Add precompile interfaces for Multi-Constraint Pricer

Author: eljobe

ArbAggregator.sol

@@ -41,7 +41,10 @@ interface ArbAggregator {
     /// This reverts unless called by the batch poster, its fee collector, or a chain owner
     /// @param batchPoster The batch poster to set the fee collector for
     /// @param newFeeCollector The new fee collector to set
-    function setFeeCollector(address batchPoster, address newFeeCollector) external;
+    function setFeeCollector(
+        address batchPoster,
+        address newFeeCollector
+    ) external;
 
     /// @notice Deprecated, always returns zero
     /// @notice Get the tx base fee (in approximate L1 gas) for aggregator
@@ -56,5 +59,8 @@ interface ArbAggregator {
     /// Revert if feeInL1Gas is outside the chain's allowed bounds
     /// @param aggregator The aggregator to set the fee for
     /// @param feeInL1Gas The base fee in L1 gas
-    function setTxBaseFee(address aggregator, uint256 feeInL1Gas) external;
+    function setTxBaseFee(
+        address aggregator,
+        uint256 feeInL1Gas
+    ) external;
 }

ArbDebug.sol

@@ -13,7 +13,10 @@ interface ArbDebug {
     function becomeChainOwner() external;
 
     /// @notice Emit events with values based on the args provided
-    function events(bool flag, bytes32 value) external payable returns (address, uint256);
+    function events(
+        bool flag,
+        bytes32 value
+    ) external payable returns (address, uint256);
 
     /// @notice Tries (and fails) to emit logs in a view context
     function eventsView() external view;

ArbFunctionTable.sol

@@ -22,5 +22,8 @@ interface ArbFunctionTable {
     ) external view returns (uint256);
 
     /// @notice No-op
-    function get(address addr, uint256 index) external view returns (uint256, bool, uint256);
+    function get(
+        address addr,
+        uint256 index
+    ) external view returns (uint256, bool, uint256);
 }

ArbGasInfo.sol

@@ -49,7 +49,10 @@ interface ArbGasInfo {
     function getPricesInArbGas() external view returns (uint256, uint256, uint256);
 
     /// @notice Get the gas accounting parameters. `gasPoolMax` is always zero, as the exponential pricing model has no such notion.
+    /// @notice Starting from ArbOS version 50, returns `speedLimitPerSecond` as the target from the longest-period constraint.
+    /// @notice For new integrations, prefer `getMaxBlockGasLimit` and `getGasPricingConstraints`.
     /// @return (speedLimitPerSecond, gasPoolMax, maxBlockGasLimit)
+    /// @dev Deprecated starting from ArbOS version 50.
     function getGasAccountingParams() external view returns (uint256, uint256, uint256);
 
     /// @notice Get the maxTxGasLimit
@@ -80,12 +83,21 @@ interface ArbGasInfo {
     function getCurrentTxL1GasFees() external view returns (uint256);
 
     /// @notice Get the backlogged amount of gas burnt in excess of the speed limit
+    /// @notice Starting from ArbOS version 50, returns the backlog of the longest-period constraint among all configured constraints.
+    /// @notice For new integrations, prefer `getGasPricingConstraints`.
+    /// @dev Deprecated starting from ArbOS version 50.
     function getGasBacklog() external view returns (uint64);
 
     /// @notice Get how slowly ArbOS updates the L2 basefee in response to backlogged gas
+    /// @notice Starting from ArbOS version 50, returns the inertia value derived from the longest-period constraint
+    /// @notice For new integrations, prefer `getGasPricingConstraints`.
+    /// @dev Deprecated starting from ArbOS version 50.
     function getPricingInertia() external view returns (uint64);
 
     /// @notice Get the forgivable amount of backlogged gas ArbOS will ignore when raising the basefee
+    /// @notice Starting from ArbOS version 50, this function always returns zero.
+    /// @notice There is no tolerance for backlogged gas in the new pricing model.
+    /// @dev Deprecated starting from ArbOS version 50.
     function getGasBacklogTolerance() external view returns (uint64);
 
     /// @notice Returns the surplus of funds for L1 batch posting payments (may be negative).
@@ -120,4 +132,17 @@ interface ArbGasInfo {
     /// @notice Returns the L1 pricing surplus as of the last update (may be negative).
     /// @notice Available in ArbOS version 20 and above
     function getLastL1PricingSurplus() external view returns (int256);
+
+    /// @notice Get the maximum block gas limit
+    /// @notice Available in ArbOS version 50 and above
+    function getMaxBlockGasLimit() external view returns (uint64);
+
+    /// @notice Get the current gas pricing constraints used by the Multi-Constraint Pricer.
+    /// @notice Each constraint contains the following values:
+    ///         - `uint64 gas_target_per_second`: target gas usage per second
+    ///         - `uint64 time_constant_seconds`: time constant in seconds
+    ///         - `uint64 backlog`: current backlog in gas units
+    /// @return constraints Array of triples (gas_target_per_second, time_constant_seconds, backlog)
+    /// @notice Available in ArbOS version 50 and above.
+    function getGasPricingConstraints() external view returns (uint64[3][] memory constraints);
 }

ArbOwner.sol

@@ -77,6 +77,9 @@ interface ArbOwner {
     ) external;
 
     /// @notice Set the computational speed limit for the chain
+    /// @notice Starting from ArbOS version 50, this function always returns an error.
+    /// @notice Use `setGasPricingConstraints` instead, which supports configuring multiple constraints.
+    /// @dev Deprecated starting from ArbOS version 50.
     function setSpeedLimit(
         uint64 limit
     ) external;
@@ -93,11 +96,17 @@ interface ArbOwner {
     ) external;
 
     /// @notice Set the L2 gas pricing inertia
+    /// @notice Starting from ArbOS version 50, this function always returns an error.
+    /// @notice Use `setGasPricingConstraints` instead, which supports configuring multiple constraints.
+    /// @dev Deprecated starting from ArbOS version 50.
     function setL2GasPricingInertia(
         uint64 sec
     ) external;
 
     /// @notice Set the L2 gas backlog tolerance
+    /// @notice Starting from ArbOS version 50, this function always returns an error.
+    /// @notice Use `setGasPricingConstraints` instead, which supports configuring multiple constraints.
+    /// @dev Deprecated starting from ArbOS version 50.
     function setL2GasBacklogTolerance(
         uint64 sec
     ) external;
@@ -121,7 +130,10 @@ interface ArbOwner {
     ) external;
 
     /// @notice Upgrades ArbOS to the requested version at the requested timestamp
-    function scheduleArbOSUpgrade(uint64 newVersion, uint64 timestamp) external;
+    function scheduleArbOSUpgrade(
+        uint64 newVersion,
+        uint64 timestamp
+    ) external;
 
     /// @notice Sets equilibration units parameter for L1 price adjustment algorithm
     function setL1PricingEquilibrationUnits(
@@ -217,7 +229,10 @@ interface ArbOwner {
     /// @notice Available in ArbOS version 30 and above
     /// @param gas amount of gas paid in increments of 256 when not the program is not cached
     /// @param cached amount of gas paid in increments of 64 when the program is cached
-    function setWasmMinInitGas(uint8 gas, uint16 cached) external;
+    function setWasmMinInitGas(
+        uint8 gas,
+        uint16 cached
+    ) external;
 
     /// @notice Sets the linear adjustment made to program init costs.
     /// @notice Available in ArbOS version 30 and above
@@ -268,6 +283,18 @@ interface ArbOwner {
         bool enable
     ) external;
 
+    /// @notice Sets the list of gas pricing constraints for the Multi-Constraint Pricer.
+    /// @notice Replaces the existing constraints configuration and sets each constraint's starting backlog value.
+    /// @notice All existing backlogs are replaced by the provided values.
+    /// @notice Any changes to gas targets, periods, or starting backlogs may cause immediate price fluctuations.
+    /// @notice Operators are fully responsible for the resulting behavior and should adjust parameters carefully.
+    /// @notice Use ArbGasInfo.getGasPricingConstraints() to retrieve the current configuration.
+    /// @notice Available in ArbOS version 50 and above.
+    /// @param constraints Array of triples (gas_target_per_second, period_seconds, starting_backlog_value)
+    function setGasPricingConstraints(
+        uint64[3][] calldata constraints
+    ) external;
+
     /// Emitted when a successful call is made to this precompile
     event OwnerActs(bytes4 indexed method, address indexed owner, bytes data);
 }

ArbStatistics.sol

@@ -15,8 +15,5 @@ interface ArbStatistics {
     ///      Number of transaction receipt issued,
     ///      Number of contracts created,
     ///    )
-    function getStats()
-        external
-        view
-        returns (uint256, uint256, uint256, uint256, uint256, uint256);
+    function getStats() external view returns (uint256, uint256, uint256, uint256, uint256, uint256);
 }