Remove arguments that are unnecessarily passed around

contracts/staking/contracts/src/stake/MixinStake.sol

@@ -187,10 +187,6 @@ contract MixinStake is
         // Sanity check the pool we're delegating to exists.
         _assertStakingPoolExists(poolId);
 
-        // Cache amount delegated to pool by staker.
-        IStructs.StoredBalance memory initDelegatedStake =
-            _loadUnsyncedBalance(_delegatedStakeToPoolByOwner[staker][poolId]);
-
         // Increment how much stake the staker has delegated to the input pool.
         _increaseNextBalance(
             _delegatedStakeToPoolByOwner[staker][poolId],
@@ -200,16 +196,9 @@ contract MixinStake is
         // Increment how much stake has been delegated to pool.
         _increaseNextBalance(_delegatedStakeByPoolId[poolId], amount);
 
-        // Synchronizes reward state in the pool that the owner is delegating
-        // to.
-        IStructs.StoredBalance memory finalDelegatedStake =
-            _loadSyncedBalance(_delegatedStakeToPoolByOwner[staker][poolId]);
-
         _withdrawAndSyncDelegatorRewards(
             poolId,
-            staker,
-            initDelegatedStake,
-            finalDelegatedStake
+            staker
         );
     }
 
@@ -227,10 +216,6 @@ contract MixinStake is
         // sanity check the pool we're undelegating from exists
         _assertStakingPoolExists(poolId);
 
-        // cache amount delegated to pool by staker
-        IStructs.StoredBalance memory initDelegatedStake =
-            _loadUnsyncedBalance(_delegatedStakeToPoolByOwner[staker][poolId]);
-
         // decrement how much stake the staker has delegated to the input pool
         _decreaseNextBalance(
             _delegatedStakeToPoolByOwner[staker][poolId],
@@ -240,16 +225,9 @@ contract MixinStake is
         // decrement how much stake has been delegated to pool
         _decreaseNextBalance(_delegatedStakeByPoolId[poolId], amount);
 
-        // synchronizes reward state in the pool that the owner is undelegating
-        // from
-        IStructs.StoredBalance memory finalDelegatedStake =
-            _loadSyncedBalance(_delegatedStakeToPoolByOwner[staker][poolId]);
-
         _withdrawAndSyncDelegatorRewards(
             poolId,
-            staker,
-            initDelegatedStake,
-            finalDelegatedStake
+            staker
         );
     }
 

contracts/staking/contracts/src/staking_pools/MixinStakingPoolRewards.sol

@@ -44,23 +44,15 @@ contract MixinStakingPoolRewards is
     {
         address member = msg.sender;
 
-        IStructs.StoredBalance memory finalDelegatedStake =
-            _loadSyncedBalance(_delegatedStakeToPoolByOwner[member][poolId]);
-
-        IStructs.StoredBalance memory initDelegatedStake =
-            _loadUnsyncedBalance(_delegatedStakeToPoolByOwner[member][poolId]);
-
         _withdrawAndSyncDelegatorRewards(
             poolId,
-            member,
-            initDelegatedStake,
-            finalDelegatedStake
+            member
         );
 
         // Update stored balance with synchronized version; this prevents
         // redundant withdrawals.
         _delegatedStakeToPoolByOwner[member][poolId] =
-            finalDelegatedStake;
+            _loadSyncedBalance(_delegatedStakeToPoolByOwner[member][poolId]);
     }
 
     /// @dev Computes the reward balance in ETH of the operator of a pool.
@@ -110,7 +102,7 @@ contract MixinStakingPoolRewards is
         );
         return _computeDelegatorReward(
             poolId,
-            _loadUnsyncedBalance(_delegatedStakeToPoolByOwner[member][poolId]),
+            member,
             unfinalizedMembersReward,
             unfinalizedMembersStake
         );
@@ -120,15 +112,9 @@ contract MixinStakingPoolRewards is
     ///      withdrawing rewards and adding/removing dependencies on cumulative rewards.
     /// @param poolId Unique id of pool.
     /// @param member of the pool.
-    /// @param initDelegatedStake The member's delegated
-    ///        balance at the beginning of this transaction.
-    /// @param finalDelegatedStake The member's delegated balance
-    ///        at the end of this transaction.
     function _withdrawAndSyncDelegatorRewards(
         bytes32 poolId,
-        address member,
-        IStructs.StoredBalance memory initDelegatedStake,
-        IStructs.StoredBalance memory finalDelegatedStake
+        address member
     )
         internal
     {
@@ -138,7 +124,7 @@ contract MixinStakingPoolRewards is
         // Compute balance owed to delegator
         uint256 balance = _computeDelegatorReward(
             poolId,
-            initDelegatedStake,
+            member,
             // No unfinalized values because we ensured the pool is already
             // finalized.
             0,
@@ -158,7 +144,7 @@ contract MixinStakingPoolRewards is
         // epoch, if necessary.
         _setCumulativeRewardDependenciesForDelegator(
             poolId,
-            finalDelegatedStake
+            member
         );
     }
 
@@ -261,13 +247,13 @@ contract MixinStakingPoolRewards is
 
     /// @dev Computes the reward balance in ETH of a specific member of a pool.
     /// @param poolId Unique id of pool.
-    /// @param unsyncedStake Unsynced delegated stake to pool by staker
+    /// @param member of the pool.
     /// @param unfinalizedMembersReward Unfinalized total members reward (if any).
     /// @param unfinalizedMembersStake Unfinalized total members stake (if any).
     /// @return reward Balance in WETH.
     function _computeDelegatorReward(
         bytes32 poolId,
-        IStructs.StoredBalance memory unsyncedStake,
+        address member,
         uint256 unfinalizedMembersReward,
         uint256 unfinalizedMembersStake
     )
@@ -282,6 +268,9 @@ contract MixinStakingPoolRewards is
             return 0;
         }
 
+        IStructs.StoredBalance memory unsyncedStake =
+            _loadUnsyncedBalance(_delegatedStakeToPoolByOwner[member][poolId]);
+
         // There can be no rewards if the last epoch when stake was synced is
         // equal to the current epoch, because all prior rewards, including
         // rewards finalized this epoch have been claimed.
@@ -368,17 +357,15 @@ contract MixinStakingPoolRewards is
     ///      A delegator always depends on the cumulative reward for the current
     ///      and next epoch, if they would still have stake in the next epoch.
     /// @param poolId Unique id of pool.
-    /// @param finalDelegatedStake Amount of stake the member has
-    ///        delegated to the pool.
+    /// @param member of the pool.
     function _setCumulativeRewardDependenciesForDelegator(
         bytes32 poolId,
-        IStructs.StoredBalance memory finalDelegatedStake
+        address member
     )
         private
     {
-        // Get the most recent cumulative reward, which will serve as a
-        // reference point when updating dependencies
-        IStructs.Fraction memory mostRecentCumulativeReward = _getMostRecentCumulativeReward(poolId);
+        IStructs.StoredBalance memory finalDelegatedStake =
+            _loadSyncedBalance(_delegatedStakeToPoolByOwner[member][poolId]);
 
         // The delegator depends on the Cumulative Reward for this epoch
         // only if they are currently staked or will be staked next epoch.
@@ -386,6 +373,10 @@ contract MixinStakingPoolRewards is
             return;
         }
 
+        // Get the most recent cumulative reward, which will serve as a
+        // reference point when updating dependencies
+        IStructs.Fraction memory mostRecentCumulativeReward = _getMostRecentCumulativeReward(poolId);
+
         // Delegator depends on the Cumulative Reward for this epoch - ensure it is set.
         if (!_isCumulativeRewardSet(_cumulativeRewardsByPool[poolId][finalDelegatedStake.currentEpoch])) {
             _forceSetCumulativeReward(

contracts/staking/contracts/test/TestDelegatorRewards.sol

@@ -110,7 +110,6 @@ contract TestDelegatorRewards is
         external
     {
         _initGenesisCumulativeRewards(poolId);
-        IStructs.StoredBalance memory initialStake = _delegatedStakeToPoolByOwner[delegator][poolId];
         IStructs.StoredBalance storage _stake = _delegatedStakeToPoolByOwner[delegator][poolId];
         _stake.isInitialized = true;
         _stake.currentEpochBalance += uint96(stake);
@@ -118,9 +117,7 @@ contract TestDelegatorRewards is
         _stake.currentEpoch = uint32(currentEpoch);
         _withdrawAndSyncDelegatorRewards(
             poolId,
-            delegator,
-            initialStake,
-            _stake
+            delegator
         );
     }
 
@@ -135,7 +132,6 @@ contract TestDelegatorRewards is
         external
     {
         _initGenesisCumulativeRewards(poolId);
-        IStructs.StoredBalance memory initialStake = _delegatedStakeToPoolByOwner[delegator][poolId];
         IStructs.StoredBalance storage _stake = _delegatedStakeToPoolByOwner[delegator][poolId];
         if (_stake.currentEpoch < currentEpoch) {
             _stake.currentEpochBalance = _stake.nextEpochBalance;
@@ -145,9 +141,7 @@ contract TestDelegatorRewards is
         _stake.currentEpoch = uint32(currentEpoch);
         _withdrawAndSyncDelegatorRewards(
             poolId,
-            delegator,
-            initialStake,
-            _stake
+            delegator
         );
     }
 
@@ -162,7 +156,6 @@ contract TestDelegatorRewards is
         external
     {
         _initGenesisCumulativeRewards(poolId);
-        IStructs.StoredBalance memory initialStake = _delegatedStakeToPoolByOwner[delegator][poolId];
         IStructs.StoredBalance storage _stake = _delegatedStakeToPoolByOwner[delegator][poolId];
         if (_stake.currentEpoch < currentEpoch) {
             _stake.currentEpochBalance = _stake.nextEpochBalance;
@@ -172,9 +165,7 @@ contract TestDelegatorRewards is
         _stake.currentEpoch = uint32(currentEpoch);
         _withdrawAndSyncDelegatorRewards(
             poolId,
-            delegator,
-            initialStake,
-            _stake
+            delegator
         );
     }