private Code processCodeFromAccount(
      final WorldUpdater worldUpdater, final Set<Address> warmAddressList, final Account contract) {
    if (contract == null) {
      return CodeV0.EMPTY_CODE;
    }

    final Hash codeHash = contract.getCodeHash();
    if (codeHash == null || codeHash.equals(Hash.EMPTY)) {
      return CodeV0.EMPTY_CODE;
    }

    if (hasCodeDelegation(contract.getCode())) {
      return delegationTargetCode(worldUpdater, warmAddressList, contract);
    }

    return messageCallProcessor.getCodeFromEVM(contract.getCodeHash(), contract.getCode());
  }
Applies a transaction to the current system state.

@param worldState The current world state
@param blockHeader The current block header
@param transaction The transaction to process
@param miningBeneficiary The address which is to receive the transaction fee
@param operationTracer The tracer to record results of each EVM operation
@param blockHashLookup The {@link BlockHashLookup} to use for BLOCKHASH operations
@return the transaction result
ethereum/core/src/main/java/org/hyperledger/besu/ethereum/mainnet/MainnetTransactionProcessor.java