/**
    @notice Update global accrual state
    @param  globalState    GlobalState  Global state of the producer token
    @param  producerToken  ERC20        Producer token contract
*/
function _globalAccrue(GlobalState storage globalState, ERC20 producerToken)
	internal
{
    uint256 totalSupply = producerToken.totalSupply();
    uint256 lastUpdate = globalState.lastUpdate;
    uint256 lastSupply = globalState.lastSupply;

    // Calculate rewards, the product of seconds elapsed and last supply
    // Only calculate and update states when needed
    if (block.timestamp != lastUpdate || totalSupply != lastSupply) {
        uint256 rewards = globalState.rewards +
            (block.timestamp - lastUpdate) *
            lastSupply;
            
            globalState.lastUpdate = block.timestamp.safeCastTo32();
            globalState.lastSupply = totalSupply.safeCastTo224();
            globalState.rewards = rewards;
   	..SNIP..
}
/**
    @notice Update user rewards accrual state
    @param  producerToken  ERC20    Rewards-producing token
    @param  user           address  User address
*/
function userAccrue(ERC20 producerToken, address user) public {
    if (address(producerToken) == address(0)) revert ZeroAddress();
    if (user == address(0)) revert ZeroAddress();

    UserState storage u = producerTokens[producerToken].userStates[user];
    uint256 balance = producerToken.balanceOf(user);

    // Calculate the amount of rewards accrued by the user up to this call
    uint256 rewards = u.rewards +
    u.lastBalance *
    (block.timestamp - u.lastUpdate);
    
    u.lastUpdate = block.timestamp.safeCastTo32();
    u.lastBalance = balance.safeCastTo224();
    u.rewards = rewards;
    ..SNIP..
}
File: PirexRewards.sol
373:     function claim(ERC20 producerToken, address user) external {
..SNIP..
395:             // Transfer the proportionate reward token amounts to the recipient
396:             for (uint256 i; i < rLen; ++i) {
397:                 ERC20 rewardToken = rewardTokens[i];
398:                 address rewardRecipient = p.rewardRecipients[user][rewardToken];
399:                 address recipient = rewardRecipient != address(0)
400:                     ? rewardRecipient
401:                     : user;
402:                 uint256 rewardState = p.rewardStates[rewardToken];
403:                 uint256 amount = (rewardState * userRewards) / globalRewards;
..SNIP..
417:     }
(rewardState * userRewards) / globalRewards
(13 * 5) / 13 = 5
[1 staked GMX * (T82 - T80) * 2esGMX/sec] + [1 staked GMX * (T84 - T83) * 1esGMX/sec]
[1 staked GMX * 3 secs * 2esGMX/sec] + [1 staked GMX * 2secs * 1esGMX/sec]
6 + 2 = 8
[4 staked GMX * 2secs * 1esGMX/sec] = 8
(rewardState * userRewards) / globalRewards
(16 * 5) / 13 = 6.15 = 6
(rewardState * userRewards) / globalRewards
(16 * 8) / 13 = 9.85 = 9
