[protocol 3.6] uint96 safe math

packages/loopring_v3/contracts/core/iface/IExchangeV3.sol

@@ -63,14 +63,14 @@ abstract contract IExchangeV3 is IExchange
         address from,
         address to,
         address token,
-        uint96  amount
+        uint    amount
     );
 
     event WithdrawalFailed(
         address from,
         address to,
         address token,
-        uint96  amount
+        uint    amount
     );
 
     event ProtocolFeesUpdated(

packages/loopring_v3/contracts/core/impl/DefaultDepositContract.sol

@@ -7,6 +7,7 @@ import "../../lib/Claimable.sol";
 import "../../lib/ERC20.sol";
 import "../../lib/ERC20SafeTransfer.sol";
 import "../../lib/MathUint.sol";
+import "../../thirdparty/SafeCast.sol";
 import "../iface/IDepositContract.sol";
 
 
@@ -24,6 +25,7 @@ contract DefaultDepositContract is IDepositContract, Claimable
     using AddressUtil       for address;
     using ERC20SafeTransfer for address;
     using MathUint          for uint;
+    using SafeCast          for uint;
 
     address public exchange;
 
@@ -108,8 +110,7 @@ contract DefaultDepositContract is IDepositContract, Claimable
 
             uint balanceAfter = checkBalance ? ERC20(token).balanceOf(address(this)) : amount;
             uint diff = balanceAfter.sub(balanceBefore);
-            amountReceived = uint96(diff);
-            require(uint(amountReceived) == diff, "OUT_OF_RANGE");
+            amountReceived = diff.toUint96();
 
             ethToReturn = msg.value;
         }

packages/loopring_v3/contracts/core/impl/libexchange/ExchangeDeposits.sol

@@ -4,6 +4,7 @@ pragma solidity ^0.7.0;
 pragma experimental ABIEncoderV2;
 
 import "../../../lib/AddressUtil.sol";
+import "../../../lib/MathUint96.sol";
 import "../../iface/ExchangeData.sol";
 import "./ExchangeMode.sol";
 import "./ExchangeTokens.sol";
@@ -15,9 +16,7 @@ import "./ExchangeTokens.sol";
 library ExchangeDeposits
 {
     using AddressUtil       for address payable;
-    using MathUint          for uint;
-    using MathUint          for uint64;
-    using MathUint          for uint96;
+    using MathUint96        for uint96;
     using ExchangeMode      for ExchangeData.State;
     using ExchangeTokens    for ExchangeData.State;
 
@@ -57,14 +56,14 @@ library ExchangeDeposits
         // Add the amount to the deposit request and reset the time the operator has to process it
         ExchangeData.Deposit memory _deposit = S.pendingDeposits[to][tokenID];
         _deposit.timestamp = uint64(block.timestamp);
-        _deposit.amount = _deposit.amount.add96(amountDeposited);
+        _deposit.amount = _deposit.amount.add(amountDeposited);
         S.pendingDeposits[to][tokenID] = _deposit;
 
         emit DepositRequested(
             to,
             tokenAddress,
             tokenID,
-            uint96(amountDeposited)
+            amountDeposited
         );
     }
 }

packages/loopring_v3/contracts/core/impl/libexchange/ExchangeWithdrawals.sol

@@ -34,14 +34,14 @@ library ExchangeWithdrawals
         address from,
         address to,
         address token,
-        uint96  amount
+        uint    amount
     );
 
     event WithdrawalFailed(
         address from,
         address to,
         address token,
-        uint96  amount
+        uint    amount
     );
 
     function forceWithdraw(
@@ -262,7 +262,7 @@ library ExchangeWithdrawals
                 from,
                 to,
                 token,
-                uint96(amount)
+                amount
             );
             if (from == address(0)) {
                 S.protocolFeeLastWithdrawnTime[token] = block.timestamp;
@@ -272,7 +272,7 @@ library ExchangeWithdrawals
                 from,
                 to,
                 token,
-                uint96(amount)
+                amount
             );
         }
     }

packages/loopring_v3/contracts/core/impl/libtransactions/AccountUpdateTransaction.sol

@@ -32,7 +32,7 @@ library AccountUpdateTransaction
         address owner;
         uint32  accountID;
         uint16  feeTokenID;
-        uint    fee;
+        uint96  fee;
         uint    publicKey;
         uint32  validUntil;
         uint32  nonce;

packages/loopring_v3/contracts/core/impl/libtransactions/DepositTransaction.sol

@@ -4,7 +4,7 @@ pragma solidity ^0.7.0;
 pragma experimental ABIEncoderV2;
 
 import "../../../lib/EIP712.sol";
-import "../../../lib/MathUint.sol";
+import "../../../lib/MathUint96.sol";
 import "../../../lib/SignatureUtil.sol";
 import "../../../thirdparty/BytesUtil.sol";
 import "../../iface/ExchangeData.sol";
@@ -14,15 +14,15 @@ import "../../iface/ExchangeData.sol";
 /// @author Brecht Devos - <brecht@loopring.org>
 library DepositTransaction
 {
-    using BytesUtil for bytes;
-    using MathUint  for uint;
+    using BytesUtil   for bytes;
+    using MathUint96  for uint96;
 
     struct Deposit
     {
         address owner;
         uint32  accountID;
         uint16  tokenID;
-        uint    amount;
+        uint96  amount;
     }
 
     /*event DepositProcessed(
@@ -55,7 +55,7 @@ library DepositTransaction
         // Also note the original deposit.amount can be zero!
         if (deposit.amount > 0) {
             require(pendingDeposit.amount >= deposit.amount, "INVALID_AMOUNT");
-            pendingDeposit.amount = uint96(uint(pendingDeposit.amount).sub(deposit.amount));
+            pendingDeposit.amount = pendingDeposit.amount.sub(deposit.amount);
         }
 
         // If the deposit was fully consumed, reset it so the storage is freed up

packages/loopring_v3/contracts/core/impl/libtransactions/TransferTransaction.sol

@@ -31,9 +31,9 @@ library TransferTransaction
         address from;
         address to;
         uint16  tokenID;
-        uint    amount;
+        uint96  amount;
         uint16  feeTokenID;
-        uint    fee;
+        uint96  fee;
         uint32  validUntil;
         uint32  storageID;
     }

packages/loopring_v3/contracts/core/impl/libtransactions/WithdrawTransaction.sol

@@ -42,9 +42,9 @@ library WithdrawTransaction
         address owner;
         uint32  accountID;
         uint16  tokenID;
-        uint    amount;
+        uint96  amount;
         uint16  feeTokenID;
-        uint    fee;
+        uint96  fee;
         address to;
         bytes   extraData;
         uint    minGas;

packages/loopring_v3/contracts/lib/FloatUtil.sol

@@ -3,13 +3,15 @@
 pragma solidity ^0.7.0;
 
 import "./MathUint.sol";
+import "../thirdparty/SafeCast.sol";
 
 
 /// @title Utility Functions for floats
 /// @author Brecht Devos - <brecht@loopring.org>
 library FloatUtil
 {
     using MathUint for uint;
+    using SafeCast for uint;
 
     // Decodes a decimal float value that is encoded like `exponent | mantissa`.
     // Both exponent and mantissa are in base 10.
@@ -24,14 +26,13 @@ library FloatUtil
         )
         internal
         pure
-        returns (uint value)
+        returns (uint96 value)
     {
         uint numBitsMantissa = numBits.sub(5);
         uint exponent = f >> numBitsMantissa;
         // log2(10**77) = 255.79 < 256
         require(exponent <= 77, "EXPONENT_TOO_LARGE");
         uint mantissa = f & ((1 << numBitsMantissa) - 1);
-        value = mantissa.mul(10 ** exponent);
-        require(value < (2 ** 96), "FLOAT_VALUE_TOO_LARGE");
+        value = mantissa.mul(10 ** exponent).toUint96();
     }
 }

packages/loopring_v3/contracts/lib/MathUint.sol

@@ -56,16 +56,4 @@ library MathUint
         c = a + b;
         require(c >= a, "ADD_OVERFLOW");
     }
-
-    function add96(
-        uint96 a,
-        uint96 b
-        )
-        internal
-        pure
-        returns (uint96 c)
-    {
-        c = a + b;
-        require(c >= a, "ADD_OVERFLOW");
-    }
 }

packages/loopring_v3/contracts/lib/MathUint96.sol

@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright 2017 Loopring Technology Limited.
+pragma solidity ^0.7.0;
+
+
+/// @title Utility Functions for uint
+/// @author Daniel Wang - <daniel@loopring.org>
+library MathUint96
+{
+    function add(
+        uint96 a,
+        uint96 b
+        )
+        internal
+        pure
+        returns (uint96 c)
+    {
+        c = a + b;
+        require(c >= a, "ADD_OVERFLOW");
+    }
+
+    function sub(
+        uint96 a,
+        uint96 b
+        )
+        internal
+        pure
+        returns (uint96 c)
+    {
+        require(b <= a, "SUB_UNDERFLOW");
+        return a - b;
+    }
+}