DVM 解释器，核心

包含了代码、状态、变量等信息。

• 解释、运行代码

• 存储临时数据

DVM_Interpreter

type DVM_Interpreter struct {
    SCID        string
    SC          *SmartContract
    EntryPoint  string
    f           Function
    IP          uint64              // current line number
    ReturnValue Variable            // Result of current function call
    Locals      map[string]Variable // all local variables

    Chain_inputs *Blockchain_Input // all blockchain info is available here

    State *Shared_State // all shared state between  DVM is available here

    RND *RND // this is initialized only once  while invoking entrypoint

    store *TX_Storage // mechanism to access a data store, can discard changes
}

区别于合约代码存储于交易上，持久化数据可另外存储，状态、临时变量可直接存放在解释器里。

Blockchain_Input

与链的结合（在智能合约里可用的和区块链有关的变量）

// this structure is all the inputs that are available to SC during execution
type Blockchain_Input struct {
    SCID          crypto.Key      // current smart contract which is executing
    BLID          crypto.Key      // BLID
    TXID          crypto.Key      // current TXID under which TX
    Signer        address.Address // address which signed this
    BL_HEIGHT     uint64          // current chain height under which current tx is valid
    BL_TOPOHEIGHT uint64          // current block topo height which can be used to  uniquely pinpoint the block
}

Shared_State

共享状态

// all DVMs triggered by the first call, will share this structure
// sharing this structure means RND number attacks are not possible
// all storage state is shared, this means something similar to solidity delegatecall
// this is necessary to prevent number of attacks
type Shared_State struct {
    Persistance bool // whether the results will be persistant or it's just a demo/test call

    Chain_inputs *Blockchain_Input // all blockchain info is available here

    DERO_Balance uint64 // DERO balance of this smart contract, this is loaded
    // this includes any DERO that has arrived with this TX
    DERO_Received uint64 // amount of DERO received with this TX

    DERO_Transfer map[string]uint64 // any DERO that this TX wants to send OUT
    // transfers are only processed after the contract has terminated successfully

    RND   *RND        // this is initialized only once  while invoking entrypoint
    Store *TX_Storage // mechanism to access a data store, can discard changes

    Monitor_recursion         int64 // used to control recursion amount 64 calls are more than necessary
    Monitor_lines_interpreted int64 // number of lines interpreted
    Monitor_ops               int64 // number of ops evaluated, for expressions, variables
}