The Comp Speeds Branch on Mainnet (#161)

* Add Arr00's changes for split COMP distributions
- Adds compBorrowSpeeds and compSupplySpeeds to ComptrollerV6Storage
- Change _setCompSpeed to _setCompSpeeds - one function call to update distribution speeds for multiple markets
- Change signature of setCompSpeedInternal - compSpeed split up into two parts: compSupplySpeed and compBorrowSpeed

* Update setCompSpeedInternal to update COMP speeds and accruals using compSupplySpeeds and compBorrowSpeeds

* Fix compilation errors in Comptroller

* Update tests to use new split COMP distribution changes

* Update tests and frameworks to support the new COMP distributions

* Add tests for setting varying supply and borrow rates

* Fix bugs in Comptroller#updateCompSupplyIndex and Comptroller#updateCompBorrowIndex
- compSupplySpeeds and compBorrowSpeeds were flipped

* Add tests for one-sided COMP distribution rates
- These tests have been manually verified to fail when they are expected to fail => they work well

* Add upgrade hooks for split COMP reward distributions

* Add TODO

* Update gas costs

* Add market initialization and update market state info
- Supply state and borrow state now initialized when a market is added, ensuring market state indices are always set

* Modify upgrade hook to ensure all market state indices are set

* Simplify setCompSpeedInternal logic
- Now that market state indices are non lazily set, we can simply update market states when updating COMP speeds

* Adjust comments in Comptroller

* Add COMP accrual optimizations
- Adds changes from PR #173
- Second mint with comp accrued: reduced by 695
- Claim comp: reduced by 1268

* Add comments to accrual functions in Comptroller

* Update FlywheelTest to account for initialization of borrow/supply state indices

* Update Flywheel scenario test to use the latest Comptroller
- Old scen test used ComptrollerG3
- Removed test for removed function which never actually worked

* Update mainnet network config and abi to current (taken from compound-config)

* Fix split COMP rewards upgrade hook
- We need to call the upgrade function using the delegator address to use the storage at that contract address

* Add Comptroller upgrade simulation
- Asserts that the upgrade proposal passes
- Asserts that old comp speeds are deleted
- Asserts that new comp speeds are the same as they were previously
- Asserts that market state indices are the same post upgrade, with 0 values initialized to 1e36
- Asserts that the 2 comp speed bugs were fixed
- Asserts that the new _setCompSpeeds function works
- Asserts that comp rewards accrual works

* Refactor updateCompSupplyIndex and updateCompBorrowIndex slightly
- Stores blockNumber as uint32 for safety

* Update gas costs

* Make style adjustment and fix typo

* Update uninitialized rewards market block numbers in _upgradeSplitCompRewards

* new branch

* add new scen

* add cases to new flywheel scen

* Fix bug in distributeBorrowerComp identified by Coburn
- Note: This change significantly increases gas usage (claim gas usage increased by 12K iirc)

* Improve distributeBorrowerComp efficiency
- Don't distribute borrower COMP (or update the user's borrow state) if the user is not in the borrower market.
- Decreases gas usage of claim by 35K

* Simplify distributeBorrowerComp
- Removed the (borrowerIndex > 0) check
- Since market state indices are always set now, this condition will always evaluate to true

* Improve logic in borrowAllowed
- It's possible that a borrower can be added to a market even if borrowAllowed returns an error. This can lead to inefficiences and possibly other problems.
- This commit prevents this from happening

* Add number fetcher to scenario runner

* Move test from CompSpeed to Flywheel

* Add new CompSpeed scenario tests

* Remove old Flywheel scenario tests

* Rename new Flywheel scen test to the old name

* Add tests to Flywheel scenario tests
- Ensures supply and borrow states properly initialized
- Ensures COMP is accrued correctly when COMP rewards are added (after market activation), removed, then added again
  - This test covers the COMP speed bug identified on August 09, 2021

* Revert market membership changes
- The logic didn't flow properly

* Fix subtraction underflow problem
- Underflow occurs when calling distributeBorrowerComp on markets whose borrowState.index didn't start at 1e36.
- The COMP rewards on those markets work fine, so we just need to make a fix for people borrowing cMKR, cAAVE, and the other new markets whose indices haven't been set yet, which this commit does.

* Increase gas limit in claimComp test
- The change to distributeBorrowerComp to account for borrowers with uninitialized state indices increased the gas costs unfortunately

* Add Coburn's scenario test for the flywheel
- Ensures new COMP speeds apply to both prior borrowers+suppliers and later borrowers+suppliers correctly

* Add another test to Flywheel scen tests
- Ensures new COMP speeds apply to both prior borrowers+suppliers and later borrowers+suppliers correctly w/ uninitialized prior borrower/supplier state indices

* Upgrade Grants simulation tests

* Make distributeSupplierComp logic match distributeBorrowerComp logic

* Update gas costs
- Oof, the necessary change to distributeSupplierComp increased the gas cost of claim
- Lastly, gm

Co-authored-by: TRiLeZ <[email protected]>
Co-authored-by: Aryeh Greenberg <[email protected]>

contracts/ComptrollerStorage.sol

@@ -143,3 +143,11 @@ contract ComptrollerV5Storage is ComptrollerV4Storage {
     /// @notice Last block at which a contributor's COMP rewards have been allocated
     mapping(address => uint) public lastContributorBlock;
 }
+
+contract ComptrollerV6Storage is ComptrollerV5Storage {
+    /// @notice The rate at which comp is distributed to the corresponding borrow market (per block)
+    mapping(address => uint) public compBorrowSpeeds;
+
+    /// @notice The rate at which comp is distributed to the corresponding supply market (per block)
+    mapping(address => uint) public compSupplySpeeds;
+}

gasCosts.json

@@ -207,11 +207,11 @@
   "opcodes": {}
  },
  "unitroller second mint with comp accrued": {
-  "fee": 119362,
+  "fee": 118632,
   "opcodes": {}
  },
  "unitroller claim comp": {
-  "fee": 144374,
+  "fee": 157456,
   "opcodes": {}
  }
 }