From e993d44f766bd55ab1970d1c18b9fc16cffd2750 Mon Sep 17 00:00:00 2001
From: Ignacio Mazzara <nachomazzara@gmail.com>
Date: Sun, 14 Feb 2021 20:02:06 -0300
Subject: [PATCH] feat: reduce gas cost by prevent reading again from storage

---
 contracts/root/RootChainManager/RootChainManager.sol | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/contracts/root/RootChainManager/RootChainManager.sol b/contracts/root/RootChainManager/RootChainManager.sol
index 009092f3..b232b27a 100644
--- a/contracts/root/RootChainManager/RootChainManager.sol
+++ b/contracts/root/RootChainManager/RootChainManager.sol
@@ -287,12 +287,13 @@ contract RootChainManager is
         address rootToken,
         bytes memory depositData
     ) private {
+        bytes32 tokenType = tokenToType[rootToken];
         require(
             rootToChildToken[rootToken] != address(0x0) &&
-               tokenToType[rootToken] != 0,
+               tokenType != 0,
             "RootChainManager: TOKEN_NOT_MAPPED"
         );
-        address predicateAddress = typeToPredicate[tokenToType[rootToken]];
+        address predicateAddress = typeToPredicate[tokenType];
         require(
             predicateAddress != address(0),
             "RootChainManager: INVALID_TOKEN_TYPE"
@@ -407,7 +408,7 @@ contract RootChainManager is
 
         ITokenPredicate(predicateAddress).exitTokens(
             _msgSender(),
-            childToRootToken[childToken],
+            rootToken,
             logRLP.toRlpBytes()
         );
     }