woot! we are committing trie nodes

contracts/MIPSMemory.sol

@@ -82,12 +82,12 @@ contract MIPSMemory {
     proofs[stateHash][addr] = proof;
   }*/
 
-  function WriteMemory(bytes32 stateHash, uint32 addr, uint32 value) public view returns (bytes32) {
+  function WriteMemory(bytes32 stateHash, uint32 addr, uint32 value) public returns (bytes32) {
     require(addr & 3 == 0, "write memory must be 32-bit aligned");
     return Lib_MerkleTrie.update(tb(addr>>2), tb(value), trie, stateHash);
   }
 
-  function WriteBytes32(bytes32 stateHash, uint32 addr, bytes32 val) public view returns (bytes32) {
+  function WriteBytes32(bytes32 stateHash, uint32 addr, bytes32 val) public returns (bytes32) {
     for (uint32 i = 0; i < 32; i += 4) {
       uint256 tv = uint256(val>>(224-(i*8)));
       stateHash = WriteMemory(stateHash, addr+i, uint32(tv));

contracts/lib/Lib_MerkleTrie.sol

@@ -74,7 +74,6 @@ library Lib_MerkleTrie {
         bytes32 _root
     )
         internal
-        view
         returns (
             bytes32 _updatedRoot
         )
@@ -87,7 +86,7 @@ library Lib_MerkleTrie {
         (TrieNode[] memory proof, uint256 pathLength, bytes memory keyRemainder, ) = _walkNodePath(trie, _key, _root);
         TrieNode[] memory newPath = _getNewPath(proof, pathLength, keyRemainder, _value);
 
-        return _getUpdatedTrieRoot(newPath, _key);
+        return _getUpdatedTrieRoot(newPath, _key, trie);
     }
 
     function getRawNode(bytes memory encoded) private view returns (TrieNode memory) {
@@ -437,10 +436,10 @@ library Lib_MerkleTrie {
      */
     function _getUpdatedTrieRoot(
         TrieNode[] memory _nodes,
-        bytes memory _key
+        bytes memory _key,
+        mapping(bytes32 => bytes) storage trie
     )
         private
-        pure
         returns (
             bytes32 _updatedRoot
         )
@@ -487,6 +486,9 @@ library Lib_MerkleTrie {
 
             // Compute the node hash for the next iteration.
             previousNodeHash = _getNodeHash(currentNode.encoded);
+            if (currentNode.encoded.length >= 32) {
+                trie[keccak256(currentNode.encoded)] = currentNode.encoded;
+            }
         }
 
         // Current node should be the root at this point.