Reorganize VM/interpreter + cleanup (#52)

* Move and cleanup interpreter files - prepare for redesign of VM

* fix call comment aobut recursive dependencies

* memory: use a template again and avoid (?) a cstring-> string conversion

* Fix stack test regression

* Fix recursive dependency on logging_ops, test_vm_json compiles but regression :/

* Fix signextend regression

* Fix 3 signed test and sha3 test

nimbus/chain.nim

@@ -1,106 +0,0 @@
-# Nimbus
-# Copyright (c) 2018 Status Research & Development GmbH
-# Licensed under either of
-#  * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
-#  * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
-# at your option. This file may not be copied, modified, or distributed except according to those terms.
-
-import
-  tables, stint, eth_common, eth_keys,
-  ./logging, ./constants, ./errors, ./validation, ./utils/hexadecimal, ./vm/base, ./db/db_chain,
-  ./utils/header, ./vm/forks/f20150730_frontier/frontier_vm
-
-type
-  Chain* = ref object
-    ## An Chain is a combination of one or more VM classes.  Each VM is associated
-    ## with a range of blocks.  The Chain class acts as a wrapper around these other
-    ## VM classes, delegating operations to the appropriate VM depending on the
-    ## current block number.
-    header*: BlockHeader
-    logger*: Logger
-    networkId*: string
-    vmsByRange*: seq[tuple[blockNumber: UInt256, vmk: VMkind]] # TODO: VM should actually be a runtime typedesc(VM)
-    importBlock*: bool
-    validateBlock*: bool
-    db*: BaseChainDB
-    fundedAddress*: EthAddress
-    fundedAddressInitialBalance*: int
-    fundedAddressPrivateKey*: PrivateKey
-
-  GenesisParams* = ref object
-    blockNumber*: BlockNumber
-    difficulty*: UInt256
-    gasLimit*: GasInt
-    parentHash*: Hash256
-    coinbase*: EthAddress
-    nonce*: string
-    mixHash*: Hash256
-    extraData*: string
-    timestamp*: EthTime
-    stateRoot*: Hash256
-
-  FundedAddress* = ref object
-    balance*: Int256
-    nonce*: int
-    code*: string
-
-
-proc configureChain*(name: string, blockNumber: UInt256, vmk: VMKind, importBlock: bool = true, validateBlock: bool = true): Chain =
-  new(result)
-  result.vmsByRange = @[(blockNumber: blockNumber, vmk: vmk)]
-  result.importBlock = importBlock
-  result.validateBlock = validateBlock
-
-proc fromGenesis*(
-    chain: Chain,
-    chainDB: BaseChainDB,
-    genesisParams: GenesisParams,
-    genesisState: Table[string, FundedAddress]): Chain =
-  ## Initialize the Chain from a genesis state
-  var stateDB = chaindb.getStateDB(BLANK_ROOT_HASH)
-  # TODO
-  # for account, accountData in genesisState:
-  #   stateDB.setBalance(account, accountData.balance)
-  #   stateDB.setNonce(account, accountData.nonce)
-  #   stateDB.setCode(account, accountData.code)
-
-  new(result)
-  result.db = chainDB
-  result.header = BlockHeader()
-  result.logger = logging.getLogger("evm.chain.chain.Chain")
-  result.importBlock = chain.importBlock
-  result.validateBlock = chain.validateBlock
-  result.vmsByRange = chain.vmsByRange
-  # TODO
-  # chainDB.persistBlockToDB(result.getBlock)
-
-
-proc getVMClassForBlockNumber*(chain: Chain, blockNumber: BlockNumber): VMKind =
-  ## Returns the VM class for the given block number
-  # TODO - Refactoring: superseded by newNimbusVM for the time being #https://github.com/status-im/nimbus/pull/37
-  # TODO - Refactoring: redundant with constants.nim `toFork`
-  # TODO should the return value be a typedesc?
-
-  # TODO: validate_block_number
-  for idx in countdown(chain.vmsByRange.high, chain.vmsByRange.low):
-    let (n, vmk) = chain.vmsByRange[idx]
-    if blockNumber >= n:
-      return vmk
-
-  raise newException(ValueError, "VM not found for block #" & $blockNumber) # TODO: VMNotFound exception
-
-# TODO - Refactoring: superseded by newNimbusVM for the time being #https://github.com/status-im/nimbus/pull/37
-
-proc getVM*(chain: Chain, header: BlockHeader): VM =
-  ## Returns the VM instance for the given block number
-  # TODO - Refactoring: superseded by newNimbusVM for the time being #https://github.com/status-im/nimbus/pull/37
-  # TODO - Refactoring: redundant with constants.nim `toFork`
-  # shadowing input param
-  let vm_class = chain.getVMClassForBlockNumber(header.blockNumber)
-
-  case vm_class:
-  of vmkFrontier: result = newFrontierVM(header, chain.db)
-  else:
-    raise newException(ValueError, "Chain: only FrontierVM is implemented")
-
-proc getVM*(chain: Chain): VM {.inline.} = getVM(chain, chain.header)

nimbus/constants.nim

@@ -2,103 +2,6 @@
 import
   stint, math, strutils, utils/padding, eth_common
 
-proc int256*(i: int): Int256 =
-  i.i256
-
-# template i256*(i: int): Int256 =
-#   i.initBigInt
-
-template i256*(i: Int256): Int256 =
-  i
-
-template u256*(i: int): UInt256 =
-  i.uint.u256
-
-template u256*(i: UInt256): UInt256 =
-  i
-
-template getInt*(i: int): int =
-  i
-
-# TODO
-# We'll have a fast fixed i256, for now this works
-
-proc `==`*(a: Int256, b: int): bool =
-  a == b.i256
-
-proc `!=`*(a: Int256, b: int): bool =
-  a != b.i256
-
-proc `==`*(a: UInt256, b: int): bool =
-  a == b.u256
-
-proc `!=`*(a: UInt256, b: int): bool =
-  a != b.u256
-
-# proc `^`*(base: int; exp: int): UInt256 =
-#   let base = base.u256
-#   var ex = exp
-#   result = 1.u256
-#   while ex > 0:
-#     result = result * base
-#     dec(ex)
-
-proc `^`*(left: Int256, right: int): Int256 =
-  var value = right.i256
-  result = 1.i256
-  var m = right.i256
-  while value > 0.i256:
-    result = result * m
-    value -= 1.i256
-
-proc `^`*(left: UInt256, right: UInt256): UInt256 =
-  var value = right
-  result = 1.u256
-  var m = right.u256
-  while value > 0.u256:
-    result = result * m
-    value -= 1.u256
-
-proc `^`*(left: UInt256, right: int): UInt256 =
-  left ^ right.u256
-
-proc `>`*(a: Int256, b: int): bool =
-  a > b.i256
-
-proc `<`*(a: Int256, b: int): bool =
-  a < b.i256
-
-proc `>`*(a: UInt256, b: int): bool =
-  a > b.u256
-
-proc `<`*(a: UInt256, b: int): bool =
-  a < b.u256
-
-proc `mod`*(a: Int256, b: int): Int256 =
-  a mod b.i256
-
-proc `div`*(a: Int256, b: int): Int256 =
-  a div b.i256
-
-proc `mod`*(a: UInt256, b: int): UInt256 =
-  a mod b.u256
-
-proc `div`*(a: UInt256, b: int): UInt256 =
-  a div b.u256
-
-template mapOp(op: untyped): untyped =
-  proc `op`*(left: Int256, right: int): Int256 =
-    result = left.i256
-    result = `op`(result, right.i256)
-
-  proc `op`*(left: UInt256, right: int): UInt256 =
-    result = left.u256
-    result = `op`(result, right.u256)
-
-mapOp(`and`)
-mapOp(`or`)
-mapOp(`xor`)
-
 proc default(t: typedesc): t = discard
 
 # constants
@@ -108,7 +11,7 @@ let
   INT_256_MAX_AS_UINT256* =       cast[Uint256](high(Int256))
   NULLBYTE* =                     "\x00"
   EMPTYWORD* =                    repeat(NULLBYTE, 32)
-  UINT160CEILING*: UInt256 =      2.u256 ^ 160
+  UINT160CEILING*: UInt256 =      2.u256.pow(160)
   ZERO_ADDRESS* =                 default(EthAddress)
   CREATE_CONTRACT_ADDRESS* =      ZERO_ADDRESS
   ZERO_HASH32* =                  Hash256()
@@ -133,14 +36,6 @@ let
   MAX_UNCLE_DEPTH* =              6.u256
   MAX_UNCLES* =                   2.u256
 
-  SECPK1_P*: UInt256 =            2.u256 ^ 256 - 2.u256 ^ 32 - 977.u256
-  SECPK1_N*: UInt256 =            "115792089237316195423570985008687907852837564279074904382605163141518161494337".u256
-  SECPK1_A* =                     0.u256
-  SECPK1_B* =                     7.u256
-  SECPK1_Gx* =                    0.u256
-  SECPK1_Gy* =                    0.u256
-  SECPK1_G* =                     (SECPK1Gx, SECPK1Gy)
-
   EMPTY_UNCLE_HASH* =             "1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347".toDigest
 
   GENESIS_BLOCK_NUMBER* =         0.u256

nimbus/db/state_db.nim

@@ -6,9 +6,8 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  eth_common, tables,
+  eth_common, tables, nimcrypto, stint, rlp,
-  ../constants, ../errors, ../validation, ../account, ../logging, ../utils_numeric, .. / utils / [padding, bytes, keccak],
+  ../constants, ../errors, ../validation, ../account, ../logging
-  stint, rlp
 
 type
   AccountStateDB* = ref object
@@ -64,11 +63,11 @@ proc setStorage*(db: var AccountStateDB, address: EthAddress, slot: UInt256, val
   # let account = db.getAccount(address)
   # var storage = HashTrie(HexaryTrie(self.db, account.storageRoot))
 
-  let slotAsKey = slot.intToBigEndian.pad32.toString
+  let slotAsKey = "0x" & slot.dumpHex # Convert to a number to hex big-endian representation including prefix and leading zeros
   var storage = db.db
   # TODO fix
   if value > 0:
-    let encodedValue = rlp.encode value.intToBigEndian
+    let encodedValue = rlp.encode value.toByteArrayBE
     storage[slotAsKey] = encodedValue
   else:
     storage.del(slotAsKey)
@@ -87,13 +86,11 @@ proc getStorage*(db: var AccountStateDB, address: EthAddress, slot: UInt256): (U
   # let account = db.GetAccount(address)
   # var storage = HashTrie(HexaryTrie(self.db, account.storageRoot))
 
-  let slotAsKey = slot.intToBigEndian.pad32.toString
+  let slotAsKey = "0x" & slot.dumpHex # Convert to a number to hex big-endian representation including prefix and leading zeros
   var storage = db.db
   if storage.hasKey(slotAsKey):
-    #result = storage[slotAsKey]
+    let byteRange = storage[slotAsKey]
-    # XXX: `bigEndianToInt` can be refactored to work with a BytesRange/openarray
+    result = (readUintBE[256](byteRange.toOpenArray), true)
-    # Then we won't need to call `toSeq` here.
-    result = (storage[slotAsKey].toSeq.bigEndianToInt, true)
   else:
     result = (0.u256, false)
 
@@ -117,7 +114,7 @@ proc setCode*(db: var AccountStateDB, address: EthAddress, code: string) =
 
   var account = db.getAccount(address)
 
-  account.codeHash = keccak(code)
+  account.codeHash = keccak256.digest code
   #db.db[account.codeHash] = code
   db.setAccount(address, account)
 

nimbus/errors.nim

@@ -51,7 +51,7 @@ type
     ## Error signaling that an account has insufficient funds to transfer the
     ## requested value.
 
-  StackDepthLimit* = object of VMError
+  StackDepthError* = object of VMError
     ## Error signaling that the call stack has exceeded it's maximum allowed depth.
 
   ContractCreationCollision* = object of VMError

nimbus/nim.cfg

@@ -1 +0,0 @@
-# --warning[XDeclaredButNotUsed]:off

nimbus/opcode.nim

@@ -1,34 +0,0 @@
-# Nimbus
-# Copyright (c) 2018 Status Research & Development GmbH
-# Licensed under either of
-#  * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
-#  * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
-# at your option. This file may not be copied, modified, or distributed except according to those terms.
-
-import
-  strformat, strutils, sequtils, macros,
-  constants, logging, errors, opcode_values, computation, vm/stack, stint,
-  ./vm_types
-
-
-# Super dirty fix for https://github.com/status-im/nimbus/issues/46
-# Pending https://github.com/status-im/nimbus/issues/36
-# Disentangle opcode logic
-from logic.call import runLogic, BaseCall
-
-
-template run*(opcode: Opcode, computation: var BaseComputation) =
-  # Hook for performing the actual VM execution
-  # opcode.consumeGas(computation)
-
-  if opcode.kind == Op.Call: # Super dirty fix for https://github.com/status-im/nimbus/issues/46
-    # TODO remove this branch
-    runLogic(BaseCall(opcode), computation)
-  elif computation.gasCosts[opcode.kind].kind != GckFixed:
-    opcode.runLogic(computation)
-  else:
-    computation.gasMeter.consumeGas(computation.gasCosts[opcode.kind].cost, reason = $opcode.kind)
-    opcode.runLogic(computation)
-
-method logger*(opcode: Opcode): Logger =
-  logging.getLogger(&"vm.opcode.{opcode.kind}")

nimbus/runner.nim

@@ -1,93 +0,0 @@
-# Nimbus
-# Copyright (c) 2018 Status Research & Development GmbH
-# Licensed under either of
-#  * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
-#  * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
-# at your option. This file may not be copied, modified, or distributed except according to those terms.
-
-import
-  strformat, strutils, tables, macros,
-  constants, stint, errors, logging, vm_state, opcode_table,
-  vm / [gas_meter, stack, code_stream, memory, message, value], db / chain, computation, opcode, opcode_values, utils / [header, address],
-  logic / [arithmetic, comparison, sha3, context, block_ops, stack_ops, duplication, swap, memory_ops, storage, flow, logging_ops, invalid, call, system_ops]
-
-var mem = newMemory(pow(1024.int256, 2))
-
-var to = toCanonicalAddress("0x0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6")
-var sender = toCanonicalAddress("0xcd1722f3947def4cf144679da39c4c32bdc35681")
-
-var code = ""
-var data: seq[byte] = @[]
-
-var msg = newMessage(
-  25.int256,
-  1.int256,
-  to,
-  sender,
-  0.int256,
-  data,
-  code,
-  MessageOptions(depth: 1))
-
-var c = BaseComputation(
-  vmState: BaseVMState(
-    prevHeaders: @[],
-    chaindb: BaseChainDB(),
-    blockHeader: BlockHeader(),
-    name: "zero"),
-  msg: msg,
-  memory: mem,
-  stack: newStack(),
-  gasMeter: newGasMeter(msg.gas),
-  code: newCodeStream(code),
-  children: @[],
-  rawOutput: "",
-  returnData: "",
-  error: nil,
-  logEntries: @[],
-  shouldEraseReturnData: false,
-  accountsToDelete: initTable[string, string](),
-  opcodes: OPCODE_TABLE,
-  precompiles: initTable[string, Opcode]())
-
-# var c2 = c.applyComputation(c.vmState, c.msg)
-
-macro runOpcodes*(computation: untyped, program: untyped): untyped =
-  # runOpcodes(c):
-  #   stack: @[Value..]
-  #
-  #   Op
-  #   Op
-  #
-  # becomes
-  #
-  # c.stack.push(Value) ..
-  #
-  # c.getOpcodeFn(Op).run(c)
-  # echo c.stack ..
-  var stack = nnkStmtList.newTree()
-  for child in program[0][1][0][1]:
-    let push = quote:
-      `computation`.stack.push(`child`)
-    stack.add(push)
-
-  var ops = nnkStmtList.newTree()
-  for z, op in program:
-    if z > 0:
-      let run = quote:
-        `computation`.getOpcodeFn(`op`).run(`computation`)
-        echo `computation`.stack
-      ops.add(run)
-
-  result = nnkStmtList.newTree(stack, ops)
-
-# useful for testing simple cases
-runOpcodes(c):
-  stack: @[2.vint, 2.vint, 2.vint, 2.vint, 2.vint, 2.vint, 4.vint]
-
-  Op.Add
-  Op.Mul
-  Op.Div
-  Op.Sub
-  Op.Mul
-

nimbus/utils/bytes.nim

@@ -24,5 +24,3 @@ proc toString*(value: seq[byte]): string =
 
 proc toBytes*(value: string): seq[byte] =
   result = value.mapIt(it.byte)
-
-

nimbus/utils/header.nim

@@ -92,4 +92,8 @@ proc generateHeaderFromParentHeader*(
     # TODO: data: extraData,
   )
 
+import nimcrypto
+# TODO: required otherwise
+# eth_common/rlp_serialization.nim(18, 12) template/generic instantiation from here
+# nimcrypto/hash.nim(46, 6) Error: attempting to call undeclared routine: 'init'
 proc hash*(b: BlockHeader): Hash256 {.inline.} = rlpHash(b)

nimbus/utils/state.nim

@@ -1,20 +0,0 @@
-# Nimbus
-# Copyright (c) 2018 Status Research & Development GmbH
-# Licensed under either of
-#  * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
-#  * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
-# at your option. This file may not be copied, modified, or distributed except according to those terms.
-
-# import
-#   eth_utils, rlp, trie, evm.db.backends.memory, evm.db.chain
-
-# proc makeTrieRootAndNodes*(transactions: auto; trieClass: auto): auto =
-#   var
-#     chaindb = BaseChainDB(MemoryDB())
-#     db = chaindb.db
-#     transactionDb = trieClass(db)
-#   for index, transaction in transactions:
-#     var indexKey = rlp.encode(index)
-#     transactionDb[indexKey] = rlp.encode(transaction)
-#   return (transactionDb.rootHash, transactionDb.db.wrappedDb.kvStore)
-

nimbus/vm/base.nim

@@ -6,7 +6,9 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  ../logging, ../constants, ../errors, ../transaction, ../vm_types, ../computation, ../block_types, ../vm_state, ../vm_state_transactions, ../db/db_chain, ../utils/header
+  ../logging, ../constants, ../errors, ../transaction, ../vm_types,
+  ../block_types, ../vm_state, ../vm_state_transactions, ../db/db_chain, ../utils/header,
+  ./computation
 
 type
   VMkind* = enum

nimbus/vm/code_stream.nim

@@ -7,7 +7,7 @@
 
 import
   strformat, strutils, sequtils, parseutils, sets, macros,
-  ../logging, ../constants, ../opcode_values
+  ../logging, ../constants, ./interpreter/opcode_values
 
 type
   CodeStream* = ref object

nimbus/vm/computation.nim

@@ -7,13 +7,13 @@
 
 import
   strformat, strutils, sequtils, macros, stint, terminal, math, eth_common, byteutils, tables,
-  ./constants, ./errors, ./utils/hexadecimal, ./utils_numeric, ./validation, ./vm_state, ./logging, ./opcode_values, ./vm_types,
+  ../constants, ../errors, ../validation, ../vm_state, ../logging, ../vm_types,
-  ./vm/[code_stream, gas_meter, memory, message, stack],
+  ./interpreter/[opcode_values,gas_meter, gas_costs],
+  ./code_stream, ./memory, ./message, ./stack,
 
   # TODO further refactoring of gas cost
-  vm/forks/gas_costs,
+  ./forks/f20150730_frontier/frontier_vm_state,
-  vm/forks/f20150730_frontier/frontier_vm_state,
+  ./forks/f20161018_tangerine_whistle/tangerine_vm_state
-  vm/forks/f20161018_tangerine_whistle/tangerine_vm_state
 
 method newBaseComputation*(vmState: BaseVMState, message: Message): BaseComputation {.base.}=
   raise newException(ValueError, "Must be implemented by subclasses")
@@ -239,6 +239,27 @@ method getOpcodeFn*(computation: var BaseComputation, op: Op): Opcode =
     raise newException(InvalidInstruction,
       &"Invalid opcode {op}")
 
+# Super dirty fix for https://github.com/status-im/nimbus/issues/46
+# Pending https://github.com/status-im/nimbus/issues/36
+# Disentangle opcode logic
+from ./interpreter/opcodes_impl/call import runLogic, BaseCall
+
+template run*(opcode: Opcode, computation: var BaseComputation) =
+  # Hook for performing the actual VM execution
+  # opcode.consumeGas(computation)
+
+  if opcode.kind == Op.Call: # Super dirty fix for https://github.com/status-im/nimbus/issues/46
+    # TODO remove this branch
+    runLogic(BaseCall(opcode), computation)
+  elif computation.gasCosts[opcode.kind].kind != GckFixed:
+    opcode.runLogic(computation)
+  else:
+    computation.gasMeter.consumeGas(computation.gasCosts[opcode.kind].cost, reason = $opcode.kind)
+    opcode.runLogic(computation)
+
+method logger*(opcode: Opcode): Logger =
+  logging.getLogger(&"vm.opcode.{opcode.kind}")
+
 macro applyComputation*(t: typed, vmState: untyped, message: untyped): untyped =
   # Perform the computation that would be triggered by the VM message
   # c.applyComputation(vmState, message)

nimbus/vm/forks/README.md

@@ -0,0 +1 @@
+Folder to be deleted

nimbus/vm/interpreter.nim

@@ -5,14 +5,20 @@
 #  * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
-import strutils
+import
+  ./interpreter/[opcode_values, gas_meter, opcode_table],
+  ./interpreter/vm_forks
 
-# proc encodeHex*(value: string): string =
+from utils/utils_numeric import bigEndianToInt
-#   # return "0x" & codecs.decode(codecs.encode(value, "hex"), "utf8")
-#   return value
 
-# proc decodeHex*(value: string): string =
+import # Used in vm_types. Beware of recursive dependencies
-#   # var hexPart = value.rsplit("x", 1)[1]
+  ./code_stream, ./computation, ./stack, ./message
-#   return value
-#   # return codecs.decode(hexPart, "hex")
 
+export
+  opcode_values, gas_meter, opcode_table,
+  vm_forks
+
+export utils_numeric.bigEndianToInt
+
+export
+  code_stream, computation, stack, message

nimbus/vm/interpreter/gas_costs.nim

@@ -6,10 +6,9 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  stint, eth_common, math,
+  stint, math, eth_common, # GasInt
-  ../../utils/macros_gen_opcodes,
+  ../utils/[macros_gen_opcodes, utils_numeric],
-  ../../opcode_values,
+  ./opcode_values
-  ../../utils_numeric
 
 # Gas Fee Schedule
 # Yellow Paper Appendix G - https://ethereum.github.io/yellowpaper/paper.pdf

nimbus/vm/interpreter/gas_meter.nim

@@ -6,8 +6,8 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  strformat,
+  strformat, eth_common, # GasInt
-  ../logging, ../errors, ../vm_types
+  ../../logging, ../../errors, ../../vm_types
 
 proc newGasMeter*(startGas: GasInt): GasMeter =
   new(result)

nimbus/vm/interpreter/opcode_table.nim

@@ -6,11 +6,9 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  tables,
+  tables, stint,
-  stint, logging,
+  ../../vm_types, ./opcode_values,
-  vm / [gas_meter, stack, code_stream, memory, message], db / db_chain, computation, opcode, opcode_values, utils / [header, address],
+  opcodes_impl/[arithmetic, comparison, sha3, context, block_ops, stack_ops, duplication, swap, memory_ops, storage, flow, logging_ops, invalid, call, system_ops]
-  logic / [arithmetic, comparison, sha3, context, block_ops, stack_ops, duplication, swap, memory_ops, storage, flow, logging_ops, invalid, call, system_ops],
-  ./vm_types
 
 const
   OpLogic*: Table[Op, proc(computation: var BaseComputation){.nimcall.}] = {

nimbus/vm/interpreter/opcode_values.nim

@@ -5,7 +5,7 @@
 #  * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
-import ./utils/macros_gen_opcodes
+import ../utils/macros_gen_opcodes
 
 fill_enum_holes:
   type

nimbus/vm/interpreter/opcodes_impl/arithmetic.nim

@@ -6,9 +6,7 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  ../constants, ../utils_numeric, ../computation, ../vm_types,
+  helpers, stint, strutils, ./impl_std_import
-  .. / vm / [gas_meter, stack], ../opcode, ../opcode_values,
-  helpers, stint, strutils
 
 proc add*(computation: var BaseComputation) =
   # Addition
@@ -107,7 +105,7 @@ proc signextend*(computation: var BaseComputation) =
   if bits <= 31.u256:
     let testBit = bits.toInt * 8 + 7
     let bitPos = (1 shl testBit)
-    let mask = bitPos - 1
+    let mask = u256(bitPos - 1)
     if not (value and bitPos).isZero:
       res = value or (not mask)
     else:

nimbus/vm/interpreter/opcodes_impl/block_ops.nim

@@ -6,8 +6,7 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  times,
+  times, ./impl_std_import
-  ../constants, ../errors, ../computation, ../vm_state, ../vm_types, .. / vm / [stack], stint
 
 {.this: computation.}
 {.experimental.}

nimbus/vm/interpreter/opcodes_impl/call.nim

@@ -6,11 +6,15 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  strformat, eth_common,
+  strformat, eth_common, stint,
-  ../constants, ../vm_types, ../errors, ../computation, ../opcode_values, ../logging,
+  # ./impl_std_import # Cannot do that due to recursive dependencies
-  .. / vm / [stack, memory, gas_meter, message],
+  # .../vm/interpreter/opcodes_impl/impl_std_import.nim imports .../vm/computation.nim
-  .. / utils / [address, bytes],
+  # .../vm/computation.nim                              imports .../vm/interpreter/opcodes_impl/call.nim
-  stint
+  # .../vm/interpreter/opcodes_impl/call.nim            imports .../vm/interpreter/opcodes_impl/impl_std_import.nim
+  ../../../constants, ../../../vm_types, ../../../errors, ../../../logging,
+  ../../../utils/bytes,
+  ../../computation, ../../stack, ../../memory, ../../message,
+  ../opcode_values, ../gas_meter, ../gas_costs
 
 type
   # TODO most of these are for gas handling
@@ -68,7 +72,7 @@ method runLogic*(call: BaseCall, computation) =
   let senderBalance = 0.u256
 
   let insufficientFunds = shouldTransferValue and senderBalance < value
-  let stackTooDeep = computation.msg.depth + 1 > constants.STACK_DEPTH_LIMIT
+  let stackTooDeep = computation.msg.depth + 1 > STACK_DEPTH_LIMIT
 
   if insufficientFunds or stackTooDeep:
     computation.returnData = ""

nimbus/vm/interpreter/opcodes_impl/comparison.nim

@@ -6,8 +6,7 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  ../constants, ../utils_numeric, ../computation, ../vm/stack, ../vm_types,
+  helpers, ./impl_std_import
-  helpers, stint
 
 quasiBoolean(lt, `<`) # Lesser Comparison
 
@@ -35,7 +34,7 @@ proc iszero*(computation: var BaseComputation) =
 proc notOp*(computation: var BaseComputation) =
   var value = computation.stack.popInt()
 
-  var res = constants.UINT_256_MAX - value
+  var res = UINT_256_MAX - value
   pushRes()
 
 # TODO: seems like there is an implementation or a comment issue

nimbus/vm/interpreter/opcodes_impl/context.nim

@@ -7,9 +7,7 @@
 
 import
   strformat,
-  ../constants, ../vm_types, ../errors, ../utils_numeric, ../computation, ../vm_state, ../account, ../db/state_db, ../validation,
+  ./impl_std_import
-  .. /vm/[stack, message, gas_meter, memory, code_stream], ../utils/[address, padding, bytes], stint,
-  ../opcode_values
 
 proc balance*(computation: var BaseComputation) =
   let address = computation.stack.popAddress()

nimbus/vm/interpreter/opcodes_impl/duplication.nim

@@ -6,8 +6,7 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  macros, strformat,
+  macros, strformat, ./impl_std_import
-  ../vm_types, ../computation, ../vm/stack
 
 macro dupXX(position: static[int]): untyped =
   let name = ident(&"dup{position}")

nimbus/vm/interpreter/opcodes_impl/flow.nim

@@ -6,9 +6,7 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  strformat, stint,
+  strformat, ./impl_std_import
-  ../constants, ../vm_types, ../opcode_values, ../logging, ../errors, ../computation, .. /vm / [code_stream, stack]
-
 
 {.this: computation.}
 {.experimental.}

nimbus/vm/interpreter/opcodes_impl/helpers.nim

@@ -5,7 +5,7 @@
 #  * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
-import macros
+import macros, stint
 
 template pushRes*: untyped =
   computation.stack.push(res)
@@ -22,8 +22,8 @@ macro quasiBoolean*(name: untyped, op: untyped, signed: untyped = nil, nonzero:
     actualLeftNode = ident("leftSigned")
     actualRightNode = ident("rightSigned")
     signedNode = quote:
-      let `actualLeftNode` = unsignedToSigned(`leftNode`)
+      let `actualLeftNode` = cast[Int256](`leftNode`)
-      let `actualRightNode` = unsignedToSigned(`rightNode`)
+      let `actualRightNode` = cast[Int256](`rightNode`)
   var test = if nonzero.isNil:
       quote:
         `op`(`actualLeftNode`, `actualRightNode`)

nimbus/vm/interpreter/opcodes_impl/impl_std_import.nim

@@ -0,0 +1,22 @@
+# Nimbus
+# Copyright (c) 2018 Status Research & Development GmbH
+# Licensed under either of
+#  * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
+#  * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
+# at your option. This file may not be copied, modified, or distributed except according to those terms.
+
+import
+  stint, stint/lenient_stint,
+  ../../../constants, ../../../vm_state, ../../../vm_types, ../../../vm_types,
+  ../../../errors, ../../../logging, ../../../utils/padding, ../../../utils/bytes,
+  ../../stack, ../../computation, ../../stack, ../../memory, ../../message,
+  ../../code_stream, ../../utils/utils_numeric,
+  ../opcode_values, ../gas_meter, ../gas_costs
+
+export
+  stint, lenient_stint,
+  constants, vm_state, vm_types, vm_types,
+  errors, logging, padding, bytes,
+  stack, computation, stack, memory, message,
+  code_stream, utils_numeric,
+  opcode_values, gas_meter, gas_costs

nimbus/vm/interpreter/opcodes_impl/invalid.nim

@@ -6,7 +6,7 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  ../errors, ../vm_types, ../computation
+  ./impl_std_import
 
 proc invalidOp*(computation: var BaseComputation) =
   raise newException(InvalidInstruction, "Invalid opcode")

nimbus/vm/interpreter/opcodes_impl/logging_ops.nim

@@ -7,9 +7,7 @@
 
 import
   strformat, macros,
-  ../constants, ../errors, ../vm_types, ../computation, ../vm/[stack, memory, gas_meter, message], ../utils/bytes,
+  ./impl_std_import
-  ../opcode_values,
-  stint
 
 {.this: computation.}
 {.experimental.}
@@ -53,7 +51,7 @@ macro logXX(topicCount: static[int]): untyped =
   result.body.add(topicCode)
 
   let OpName = ident(&"Log{topicCount}")
-  let logicCode = quote:
+  let logicCode = quote do:
     `computation`.gasMeter.consumeGas(
       `computation`.gasCosts[`OpName`].m_handler(`computation`.memory.len, `memPos`, `len`),
       reason="Memory expansion, Log topic and data gas cost")
@@ -65,7 +63,6 @@ macro logXX(topicCount: static[int]): untyped =
         data = log_data)
 
   result.body.add(logicCode)
-  # echo result.repr
 
 logXX(0)
 logXX(1)

nimbus/vm/interpreter/opcodes_impl/memory_ops.nim

@@ -6,10 +6,7 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  ../constants, ../computation, ../vm_types, ../vm/[stack, memory, gas_meter], .. /utils/[padding, bytes],
+  ./impl_std_import
-  ../opcode_values,
-  stint
-
 
 {.this: computation.}
 {.experimental.}

nimbus/vm/interpreter/opcodes_impl/sha3.nim

@@ -6,21 +6,19 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  ../constants, ../utils_numeric, ../utils/[keccak, bytes], ../vm/[stack, memory, gas_meter],
+  nimcrypto,
-  ../computation, ../vm_types, ../opcode_values,
+  ./impl_std_import, ./helpers
-  ./helpers,
-  stint
 
 proc sha3op*(computation: var BaseComputation) =
   let (startPosition, size) = computation.stack.popInt(2)
   let (pos, len) = (startPosition.toInt, size.toInt)
 
   computation.gasMeter.consumeGas(
-    computation.gasCosts[Sha3].m_handler(computation.memory.len, pos, len),
+    computation.gasCosts[Op.Sha3].m_handler(computation.memory.len, pos, len),
     reason="SHA3: word gas cost"
     )
 
   computation.memory.extend(pos, len)
 
-  var res = keccak("") # TODO: stub
+  var res = keccak256.digest("") # TODO: stub
   pushRes()

nimbus/vm/interpreter/opcodes_impl/stack_ops.nim

@@ -6,8 +6,7 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  strformat, macros, sequtils,
+  strformat, macros, ./impl_std_import
-  ../vm_types, ../constants, ../errors, ../computation, .. / vm / [stack, code_stream], .. / utils / [padding, bytes], stint
 
 {.this: computation.}
 {.experimental.}

nimbus/vm/interpreter/opcodes_impl/storage.nim

@@ -6,11 +6,10 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  ../constants, ../vm_types, ../errors, ../computation, ../vm_state,
+  ./impl_std_import, strformat,
-  ../utils/header,
+  ../../../utils/header,
-  ../db/[db_chain, state_db], ../vm/[stack, gas_meter, message],
+  ../../../db/[db_chain, state_db]
-  ../opcode_values,
+
-  strformat, stint
 
 {.this: computation.}
 {.experimental.}

nimbus/vm/interpreter/opcodes_impl/swap.nim

@@ -6,8 +6,7 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  macros, strformat,
+  macros, strformat, ./impl_std_import
-  ../vm_types, ../computation, ../vm/stack
 
 macro swapXX(position: static[int]): untyped =
   let name = ident(&"swap{position}")

nimbus/vm/interpreter/opcodes_impl/system_ops.nim

@@ -7,9 +7,7 @@
 
 import
   strformat,
-  ../constants, ../vm_types, ../errors, ../computation, ../opcode, ../opcode_values, ../logging, ../vm_state, call,
+  ./call, ./impl_std_import,
-  .. / vm / [stack, gas_meter, memory, message], .. / utils / [address, hexadecimal, bytes],
-  ../opcode_values,
   stint, byteutils, eth_common
 
 {.this: computation.}
@@ -70,7 +68,7 @@ method runLogic*(create: Create, computation) =
 
   let childMsg = computation.prepareChildMessage(
     gas=0, # TODO refactor gas
-    to=constants.CREATE_CONTRACT_ADDRESS,
+    to=CREATE_CONTRACT_ADDRESS,
     value=value,
     data=cast[seq[byte]](@[]),
     code=callData.toString,

nimbus/vm/interpreter/vm_forks.nim

@@ -9,8 +9,8 @@ import
   ../../db/db_chain, ../../constants,
   ../../utils/header,
   ../base,
-  ./f20150730_frontier/frontier_vm,
+  ../forks/f20150730_frontier/frontier_vm,
-  ./f20161018_tangerine_whistle/tangerine_vm,
+  ../forks/f20161018_tangerine_whistle/tangerine_vm,
   stint
 
 # Note (mamy): refactoring is in progress (2018-05-23), this is redundant with

nimbus/vm/memory.nim

@@ -7,7 +7,8 @@
 
 import
   sequtils, stint,
-  ../constants, ../errors, ../logging, ../validation, ../utils_numeric, ../utils/bytes
+  ../constants, ../errors, ../logging, ../validation, ../utils/bytes,
+  ./utils/utils_numeric
 
 type
   Memory* = ref object
@@ -57,3 +58,7 @@ proc write*(memory: var Memory, startPosition: Natural, value: openarray[byte])
 
 template write*(memory: var Memory, startPosition: Natural, size: Natural, value: cstring) =
   memory.write(startPosition, value.toBytes)
+  # TODO ~ O(n^3):
+  #  - there is a string allocation with $ (?)
+  #  - then a conversion to seq (= new allocation) with toBytes
+  #  - then writing to memory

nimbus/vm/stack.nim

@@ -7,7 +7,7 @@
 
 import
   strformat, strutils, sequtils, macros, rlp, eth_common, nimcrypto,
-  ../errors, ../validation, ../utils_numeric, ../constants, stint, ../logging, .. / utils / bytes
+  ../errors, ../validation, ./utils/utils_numeric, ../constants, stint, ../logging, .. / utils / bytes
 
 type
   Stack* = ref object of RootObj
@@ -99,6 +99,8 @@ proc swap*(stack: var Stack, position: int) =
     raise newException(InsufficientStack,
                       &"Insufficient stack items for SWAP{position}")
 
+template getint(x: int): int = x
+
 proc dup*(stack: var Stack, position: int | UInt256) =
   ## Perform a DUP operation on the stack
   let position = position.getInt

nimbus/vm/utils/utils_numeric.nim

@@ -5,14 +5,12 @@
 #  * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
-import stint, constants, strformat, strutils, sequtils, endians, macros, utils / padding, rlp
+import
+  stint, strformat, strutils, sequtils, endians, macros, rlp,
+  ../../constants, ../../utils/padding
 
 # some methods based on py-evm utils/numeric
 
-proc intToBigEndian*(value: UInt256): Bytes {.deprecated.} =
-  result = newSeq[byte](32)
-  result[0 .. ^1] = value.toByteArrayBE()
-
 proc bigEndianToInt*(value: openarray[byte]): UInt256 =
   if value.len == 32:
     readUintBE[256](value)
@@ -22,14 +20,6 @@ proc bigEndianToInt*(value: openarray[byte]): UInt256 =
 proc log256*(value: UInt256): Natural =
   (255 - value.countLeadingZeroBits) div 8 # Compilers optimize to `shr 3`
 
-proc unsignedToSigned*(value: UInt256): Int256 =
-  0.i256
-  # TODO Remove stub (used in quasiBoolean for signed comparison)
-
-proc signedToUnsigned*(value: Int256): UInt256 =
-  0.u256
-  # TODO Remove stub (used in quasiBoolean for signed comparison)
-
 proc unsignedToPseudoSigned*(value: UInt256): UInt256 =
   result = value
   if value > INT_256_MAX_AS_UINT256:

nimbus/vm_state.nim

@@ -9,7 +9,7 @@ import
   macros, strformat, tables,
   stint, eth_common,
   ./logging, ./constants, ./errors, ./transaction, ./db/[db_chain, state_db],
-  ./utils/[state, header]
+  ./utils/header
 
 type
   BaseVMState* = ref object of RootObj

nimbus/vm_state_transactions.nim

@@ -7,7 +7,8 @@
 
 import
   strformat, tables,
-  logging, constants, errors, computation, transaction, vm_types, vm_state, block_types, db / db_chain, utils / [state, header]
+  ./logging, ./constants, ./errors, ./vm/computation,
+  ./transaction, ./vm_types, ./vm_state, ./block_types, ./db/db_chain, ./utils/header
 
 method executeTransaction(vmState: var BaseVMState, transaction: BaseTransaction): (BaseComputation, BlockHeader) {.base.}=
   # Execute the transaction in the vm

nimbus/vm_types.nim

@@ -6,13 +6,11 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  tables,
+  tables, stint, eth_common,
-  constants, vm_state,
+  ./constants, ./vm_state, ./logging,
-  opcode_values, stint, eth_common,
+  ./vm/[memory, stack, code_stream],
-  vm / [code_stream, memory, stack, forks/gas_costs],
+  ./vm/interpreter/[gas_costs, opcode_values] # TODO - will be hidden at a lower layer
-  ./logging
 
-export GasInt, gas_costs
 
 type
   BaseComputation* = ref object of RootObj
@@ -32,7 +30,7 @@ type
     accountsToDelete*:      Table[EthAddress, EthAddress]
     opcodes*:               Table[Op, proc(computation: var BaseComputation){.nimcall.}]
     precompiles*:           Table[string, Opcode]
-    gasCosts*:              GasCosts # TODO - avoid allocating memory for this const
+    gasCosts*:              GasCosts # TODO - will be hidden at a lower layer
 
   Error* = ref object
     info*:                  string

tests/all_tests.nim

@@ -10,5 +10,4 @@ import  ./test_code_stream,
         ./test_memory,
         ./test_stack,
         ./test_opcode
-        # ./test_vm
         # ./test_vm_json

tests/fixtures.nim

@@ -1,38 +0,0 @@
-# Nimbus
-# Copyright (c) 2018 Status Research & Development GmbH
-# Licensed under either of
-#  * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
-#  * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
-# at your option. This file may not be copied, modified, or distributed except according to those terms.
-
-import
-  unittest, strformat, tables, times,
-  stint, eth_keys, eth_common,
-  ../nimbus/[constants, chain, vm/base, vm/forks/f20150730_frontier/frontier_vm, utils/header, utils/address, db/db_chain, db/backends/memory_backend]
-
-proc chainWithoutBlockValidation*: Chain =
-  result = configureChain("TestChain", GENESIS_BLOCK_NUMBER, vmkFrontier, false, false)
-  let privateKey = initPrivateKey("45a915e4d060149eb4365960e6a7a45f334393093061116b197e3240065ff2d8")
-  let fundedAddr = privateKey.getPublicKey.toCanonicalAddress
-  let initialBalance = 100_000_000
-  let genesisParams = GenesisParams(
-    blockNumber: GENESIS_BLOCK_NUMBER,
-    difficulty: GENESIS_DIFFICULTY,
-    gasLimit: GENESIS_GAS_LIMIT,
-    parentHash: GENESIS_PARENT_HASH,
-    coinbase: GENESIS_COINBASE,
-    nonce: GENESIS_NONCE,
-    mixHash: GENESIS_MIX_HASH,
-    extraData: GENESIS_EXTRA_DATA,
-    timestamp: fromUnix 1501851927,
-    stateRoot: "9d354f9b5ba851a35eced279ef377111387197581429cfcc7f744ef89a30b5d4".toDigest)
-  let genesisState = {"fundedAddr": FundedAddress(balance: initialBalance.int256, nonce: 0, code: "")}.toTable()
-  result = fromGenesis(
-    result,
-    newBaseChainDB(newMemoryDB()),
-    genesisParams,
-    genesisState)
-  result.fundedAddress = fundedAddr
-  result.fundedAddressInitialBalance = initialBalance
-  result.fundedAddressPrivateKey = privateKey
-

tests/test_code_stream.nim

@@ -6,7 +6,7 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import  unittest, strutils, sequtils,
-        ../nimbus/opcode_values, ../nimbus/vm/code_stream
+        ../nimbus/vm/interpreter
 
 suite "parse bytecode":
   test "accepts bytes":

tests/test_gas_meter.nim

@@ -5,9 +5,9 @@
 #  * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
-import  unittest, macros, strformat, strutils, sequtils,
+import  unittest, macros, strformat,
         stint,
-        ../nimbus/[constants, opcode_values, errors, logging, vm_types, vm/gas_meter]
+        ../nimbus/[vm_types, errors, logging, vm/interpreter]
 
 # TODO: quicktest
 # PS: parametrize can be easily immitated, but still quicktests would be even more useful

tests/test_helpers.nim

@@ -8,9 +8,9 @@
 import
   os, macros, json, strformat, strutils, parseutils, ospaths, tables,
   stint, byteutils, eth_common, eth_keys,
-  ../nimbus/utils/[hexadecimal, address, padding],
+  ../nimbus/utils/[address, padding],
-  ../nimbus/[chain, vm_state, constants],
+  ../nimbus/[vm_state, constants],
-  ../nimbus/db/[db_chain, state_db], ../nimbus/vm/forks/f20150730_frontier/frontier_vm,
+  ../nimbus/db/[db_chain, state_db],
   ../nimbus/vm/base, ../nimbus/transaction
 
 type

tests/test_memory.nim

@@ -5,9 +5,9 @@
 #  * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
-import  unittest, macros, strformat, strutils, sequtils,
+import  unittest, sequtils,
         stint,
-        ../nimbus/[constants, opcode_values, errors, vm/memory]
+        ../nimbus/[constants, errors, vm/memory]
 
 proc memory32: Memory =
   result = newMemory()

tests/test_opcode.nim

@@ -7,14 +7,13 @@
 
 import
   unittest, stint, tables, parseutils,
-  ../nimbus/[constants, vm_types, errors, logging],
+  ../nimbus/[constants, vm_types, logging],
-  ../nimbus/[chain, vm_state, computation, opcode, opcode_table],
+  ../nimbus/vm/interpreter,
-  ../nimbus/[utils/header, utils/padding],
+  ../nimbus/utils/header,
-  ../nimbus/vm/[gas_meter, message, code_stream, stack],
-  ../nimbus/vm/forks/vm_forks,
   ../nimbus/db/[db_chain, state_db, backends/memory_backend],
-  test_helpers
+  ./test_helpers
 
+from eth_common import GasInt
 
 proc testCode(code: string, initialGas: GasInt, blockNum: UInt256): BaseComputation =
   let header = BlockHeader(blockNumber: blockNum)

tests/test_stack.nim

@@ -5,9 +5,8 @@
 #  * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
-import  unittest, macros, strformat, strutils, sequtils,
+import  unittest, stint,
-        stint,
+        ../nimbus/[constants, errors, vm/interpreter, utils/bytes]
-        ../nimbus/[constants, opcode_values, errors, utils_numeric, vm/stack, utils/bytes, utils/padding]
 
 
 template testPush(value: untyped, expected: untyped): untyped =
@@ -36,9 +35,6 @@ suite "stack":
     expect(FullStack):
       stack.push(1025)
 
-
-
-
   test "dup does not allow stack to exceed 1024":
     var stack = newStack()
     stack.push(1.u256)

tests/test_vm.nim

@@ -1,43 +0,0 @@
-# Nimbus
-# Copyright (c) 2018 Status Research & Development GmbH
-# Licensed under either of
-#  * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
-#  * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
-# at your option. This file may not be copied, modified, or distributed except according to those terms.
-
-import
-  unittest, stint, eth_common,
-  ./test_helpers, ./fixtures,
-  ../nimbus/[db/backends/memory_backend, db/state_db, chain, constants, utils/hexadecimal, vm_state],
-  ../nimbus/[vm/base, computation]
-
-import typetraits
-
-suite "VM":
-  test "Apply transaction with no validation":
-    var
-      chain = chainWithoutBlockValidation()
-      vm = chain.getVM()
-      # txIdx = len(vm.`block`.transactions) # Can't take len of a runtime field
-    let
-      recipient = parseAddress("0xa94f5374fce5edbc8e2a8697c15331677e6ebf0c")
-      amount = 100.u256
-      ethaddr_from = chain.fundedAddress
-      tx = newTransaction(vm, ethaddr_from, recipient, amount, chain.fundedAddressPrivateKey)
-      # (computation, _) = vm.applyTransaction(tx)
-      # accessLogs = computation.vmState.accessLogs
-
-    # check(not computation.isError)
-
-    let
-      # txGas = tx.gasPrice * constants.GAS_TX
-      state_db = vm.state.readOnlyStateDB
-      b = vm.`block`
-
-    echo state_db.getBalance(ethaddr_from).type.name
-
-    # check:
-    #   state_db.getBalance(ethaddr_from) == chain.fundedAddressInitialBalance - amount - txGas # TODO: this really should be i256
-    #   state_db.getBalance(recipient) == amount
-    #   b.transactions[txIdx] == tx
-    #   b.header.gasUsed == constants.GAS_TX

tests/test_vm_json.nim

@@ -9,14 +9,12 @@ import
   unittest, strformat, strutils, sequtils, tables, stint, json, ospaths, times,
   ./test_helpers,
   ../nimbus/[constants, errors, logging],
-  ../nimbus/[chain, vm_state, computation, opcode, vm_types],
+  ../nimbus/[vm_state, vm_types],
   ../nimbus/utils/[header, padding],
-  ../nimbus/vm/[gas_meter, message, code_stream, stack],
+  ../nimbus/vm/interpreter,
-  ../nimbus/vm/forks/vm_forks, ../nimbus/db/[db_chain, state_db, backends/memory_backend],
+  ../nimbus/db/[db_chain, state_db, backends/memory_backend],
   eth_common
 
-from ../nimbus/opcode_table import OpLogic
-
 proc testFixture(fixtures: JsonNode, testStatusIMPL: var TestStatus)
 
 suite "vm json tests":
@@ -47,7 +45,7 @@ proc testFixture(fixtures: JsonNode, testStatusIMPL: var TestStatus) =
   let message = newMessage(
       to = fexec{"address"}.getStr.parseAddress,
       sender = fexec{"caller"}.getStr.parseAddress,
-      value = fexec{"value"}.getHexadecimalInt.u256,
+      value = cast[uint](fexec{"value"}.getHexadecimalInt).u256, # Cast workaround for negative value
       data = fexec{"data"}.getStr.mapIt(it.byte),
       code = code,
       gas = fexec{"gas"}.getHexadecimalInt,