core: vm: refactor vm config and context

To support multiple VMs, there must be a shared execution environment for each VM,
so this pull request moved some shared component to vm.Context and
implemented the vm.ExecPack to hold the list of VM, list of VM configures,
context and some shared resources.

The adjustment includes:
* Move NoRecursion, Depth, ReadOnly, RandCallIndex, IntPool and CallGasTemp to Context.
* Adjust VM enumeration from byte to uint8, and the VMList from map to
array.
* Register VM constructor in each VM package's init function.
* Initialize all VM instance in NewExecPack.
* Remove EVMImplement, and modify EVM, such that EVM can do the same
functions with EVMImplement.

1 files changed, 5 insertions, 2 deletions

diff --git a/dex/backend.go b/dex/backend.go
index 8344c7973..97838750c 100644
--- a/dex/backend.go
+++ b/dex/backend.go
@@ -28,7 +28,8 @@ import (
 	"github.com/dexon-foundation/dexon/core"
 	"github.com/dexon-foundation/dexon/core/bloombits"
 	"github.com/dexon-foundation/dexon/core/rawdb"
-	vm "github.com/dexon-foundation/dexon/core/vm/evm"
+	"github.com/dexon-foundation/dexon/core/vm"
+	"github.com/dexon-foundation/dexon/core/vm/evm"
 	"github.com/dexon-foundation/dexon/dex/downloader"
 	"github.com/dexon-foundation/dexon/eth/filters"
 	"github.com/dexon-foundation/dexon/eth/gasprice"
@@ -118,7 +119,7 @@ func New(ctx *node.ServiceContext, config *Config) (*Dexon, error) {
 	}
 
 	var (
-		vmConfig = vm.Config{
+		evmConfig = evm.Config{
 			EnablePreimageRecording: config.EnablePreimageRecording,
 			EWASMInterpreter:        config.EWASMInterpreter,
 			EVMInterpreter:          config.EVMInterpreter,
@@ -126,6 +127,8 @@ func New(ctx *node.ServiceContext, config *Config) (*Dexon, error) {
 		}
 		cacheConfig = &core.CacheConfig{Disabled: config.NoPruning, TrieCleanLimit: config.TrieCleanCache, TrieDirtyLimit: config.TrieDirtyCache, TrieTimeLimit: config.TrieTimeout}
 	)
+	vmConfig := [vm.NUMS]interface{}{}
+	vmConfig[vm.EVM] = evmConfig
 	dex.blockchain, err = core.NewBlockChain(chainDb, cacheConfig, dex.chainConfig, dex.engine, vmConfig, nil)
 
 	// Rewind the chain in case of an incompatible config upgrade.