Adam Spitz e040e2671a
Added basic async capabilities for vm2. (#1260)
* Added basic async capabilities for vm2.

This is a whole new Git branch, not the same one as last time
(https://github.com/status-im/nimbus-eth1/pull/1250) - there wasn't
much worth salvaging. Main differences:

I didn't do the "each opcode has to specify an async handler" junk
that I put in last time. Instead, in oph_memory.nim you can see
sloadOp calling asyncChainTo and passing in an async operation.
That async operation is then run by the execCallOrCreate (or
asyncExecCallOrCreate) code in interpreter_dispatch.nim.

In the test code, the (previously existing) macro called "assembler"
now allows you to add a section called "initialStorage", specifying
fake data to be used by the EVM computation run by that test. (In
the long run we'll obviously want to write tests that for-real use
the JSON-RPC API to asynchronously fetch data; for now, this was
just an expedient way to write a basic unit test that exercises the
async-EVM code pathway.)

There's also a new macro called "concurrentAssemblers" that allows
you to write a test that runs multiple assemblers concurrently (and
then waits for them all to finish). There's one example test using
this, in test_op_memory_lazy.nim, though you can't actually see it
doing so unless you uncomment some echo statements in
async_operations.nim (in which case you can see the two concurrently
running EVM computations each printing out what they're doing, and
you'll see that they interleave).

A question: is it possible to make EVMC work asynchronously? (For
now, this code compiles and "make test" passes even if ENABLE_EVMC
is turned on, but it doesn't actually work asynchronously, it just
falls back on doing the usual synchronous EVMC thing. See
FIXME-asyncAndEvmc.)

* Moved the AsyncOperationFactory to the BaseVMState object.

* Made the AsyncOperationFactory into a table of fn pointers.

Also ditched the plain-data Vm2AsyncOperation type; it wasn't
really serving much purpose. Instead, the pendingAsyncOperation
field directly contains the Future.

* Removed the hasStorage idea.

It's not the right solution to the "how do we know whether we
still need to fetch the storage value or not?" problem. I
haven't implemented the right solution yet, but at least
we're better off not putting in a wrong one.

* Added/modified/removed some comments.

(Based on feedback on the PR.)

* Removed the waitFor from execCallOrCreate.

There was some back-and-forth in the PR regarding whether nested
waitFor calls are acceptable:

https://github.com/status-im/nimbus-eth1/pull/1260#discussion_r998587449

The eventual decision was to just change the waitFor to a doAssert
(since we probably won't want this extra functionality when running
synchronously anyway) to make sure that the Future is already
finished.
2022-11-01 11:35:46 -04:00

517 lines
16 KiB
Nim

# 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.
## EVM Opcode Handlers: Stack, Memory, Storage And Flow Operations
## ===============================================================
##
import
../../../errors,
../../async_operations,
../../code_stream,
../../computation,
../../memory,
../../stack,
../../types,
../gas_costs,
../gas_meter,
../op_codes,
../utils/utils_numeric,
./oph_defs,
./oph_helpers,
eth/common,
stint,
strformat
when not defined(evmc_enabled):
import
../../state,
../../../db/accounts_cache
# ------------------------------------------------------------------------------
# Private helpers
# ------------------------------------------------------------------------------
when evmc_enabled:
proc sstoreEvmc(c: Computation, slot, newValue: UInt256) =
let
currentValue = c.getStorage(slot)
status = c.host.setStorage(c.msg.contractAddress, slot, newValue)
gasParam = GasParams(kind: Op.Sstore, s_status: status)
gasCost = c.gasCosts[Sstore].c_handler(newValue, gasParam)[0]
c.gasMeter.consumeGas(
gasCost, &"SSTORE: {c.msg.contractAddress}[{slot}] " &
&"-> {newValue} ({currentValue})")
else:
proc sstoreImpl(c: Computation, slot, newValue: UInt256) =
let
currentValue = c.getStorage(slot)
gasParam = GasParams(
kind: Op.Sstore,
s_currentValue: currentValue)
(gasCost, gasRefund) =
c.gasCosts[Sstore].c_handler(newValue, gasParam)
c.gasMeter.consumeGas(
gasCost, &"SSTORE: {c.msg.contractAddress}[{slot}] " &
&"-> {newValue} ({currentValue})")
if gasRefund > 0:
c.gasMeter.refundGas(gasRefund)
c.vmState.mutateStateDB:
db.setStorage(c.msg.contractAddress, slot, newValue)
proc sstoreNetGasMeteringImpl(c: Computation; slot, newValue: UInt256) =
let
stateDB = c.vmState.readOnlyStateDB
currentValue = c.getStorage(slot)
gasParam = GasParams(
kind: Op.Sstore,
s_currentValue: currentValue,
s_originalValue: stateDB.getCommittedStorage(c.msg.contractAddress, slot))
(gasCost, gasRefund) = c.gasCosts[Sstore].c_handler(newValue, gasParam)
c.gasMeter.consumeGas(
gasCost, &"SSTORE EIP2200: {c.msg.contractAddress}[{slot}]" &
&" -> {newValue} ({currentValue})")
if gasRefund != 0:
c.gasMeter.refundGas(gasRefund)
c.vmState.mutateStateDB:
db.setStorage(c.msg.contractAddress, slot, newValue)
proc jumpImpl(c: Computation; jumpTarget: UInt256) =
if jumpTarget >= c.code.len.u256:
raise newException(
InvalidJumpDestination, "Invalid Jump Destination")
let jt = jumpTarget.truncate(int)
c.code.pc = jt
let nextOpcode = c.code.peek
if nextOpcode != JumpDest:
raise newException(InvalidJumpDestination, "Invalid Jump Destination")
# TODO: next check seems redundant
if not c.code.isValidOpcode(jt):
raise newException(
InvalidInstruction, "Jump resulted in invalid instruction")
# ------------------------------------------------------------------------------
# Private, op handlers implementation
# ------------------------------------------------------------------------------
const
popOp: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x50, Remove item from stack.
discard k.cpt.stack.popInt
mloadOp: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x51, Load word from memory
let (memStartPos) = k.cpt.stack.popInt(1)
let memPos = memStartPos.cleanMemRef
k.cpt.gasMeter.consumeGas(
k.cpt.gasCosts[Mload].m_handler(k.cpt.memory.len, memPos, 32),
reason = "MLOAD: GasVeryLow + memory expansion")
k.cpt.memory.extend(memPos, 32)
k.cpt.stack.push:
k.cpt.memory.read(memPos, 32)
mstoreOp: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x52, Save word to memory
let (memStartPos, value) = k.cpt.stack.popInt(2)
let memPos = memStartPos.cleanMemRef
k.cpt.gasMeter.consumeGas(
k.cpt.gasCosts[Mstore].m_handler(k.cpt.memory.len, memPos, 32),
reason = "MSTORE: GasVeryLow + memory expansion")
k.cpt.memory.extend(memPos, 32)
k.cpt.memory.write(memPos, value.toByteArrayBE)
mstore8Op: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x53, Save byte to memory
let (memStartPos, value) = k.cpt.stack.popInt(2)
let memPos = memStartPos.cleanMemRef
k.cpt.gasMeter.consumeGas(
k.cpt.gasCosts[Mstore].m_handler(k.cpt.memory.len, memPos, 1),
reason = "MSTORE8: GasVeryLow + memory expansion")
k.cpt.memory.extend(memPos, 1)
k.cpt.memory.write(memPos, [value.toByteArrayBE[31]])
# -------
sloadOp: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x54, Load word from storage.
let cpt = k.cpt # so it can safely be captured by the asyncChainTo closure below
let (slot) = cpt.stack.popInt(1)
cpt.asyncChainTo(asyncFactory(cpt).lazyDataSource.ifNecessaryGetStorage(cpt, slot)):
cpt.stack.push:
cpt.getStorage(slot)
sloadEIP2929Op: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x54, EIP2929: Load word from storage for Berlin and later
let (slot) = k.cpt.stack.popInt(1)
when evmc_enabled:
let gasCost = if k.cpt.host.accessStorage(k.cpt.msg.contractAddress, slot) == EVMC_ACCESS_COLD:
ColdSloadCost
else:
WarmStorageReadCost
k.cpt.gasMeter.consumeGas(gasCost, reason = "sloadEIP2929")
else:
k.cpt.vmState.mutateStateDB:
let gasCost = if not db.inAccessList(k.cpt.msg.contractAddress, slot):
db.accessList(k.cpt.msg.contractAddress, slot)
ColdSloadCost
else:
WarmStorageReadCost
k.cpt.gasMeter.consumeGas(gasCost, reason = "sloadEIP2929")
k.cpt.stack.push:
k.cpt.getStorage(slot)
# -------
sstoreOp: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x55, Save word to storage.
let (slot, newValue) = k.cpt.stack.popInt(2)
checkInStaticContext(k.cpt)
when evmc_enabled:
sstoreEvmc(k.cpt, slot, newValue)
else:
sstoreImpl(k.cpt, slot, newValue)
sstoreEIP1283Op: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x55, EIP1283: sstore for Constantinople and later
let (slot, newValue) = k.cpt.stack.popInt(2)
checkInStaticContext(k.cpt)
when evmc_enabled:
sstoreEvmc(k.cpt, slot, newValue)
else:
sstoreNetGasMeteringImpl(k.cpt, slot, newValue)
sstoreEIP2200Op: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x55, EIP2200: sstore for Istanbul and later
let (slot, newValue) = k.cpt.stack.popInt(2)
checkInStaticContext(k.cpt)
const SentryGasEIP2200 = 2300
if k.cpt.gasMeter.gasRemaining <= SentryGasEIP2200:
raise newException(
OutOfGas,
"Gas not enough to perform EIP2200 SSTORE")
when evmc_enabled:
sstoreEvmc(k.cpt, slot, newValue)
else:
sstoreNetGasMeteringImpl(k.cpt, slot, newValue)
sstoreEIP2929Op: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x55, EIP2929: sstore for Berlin and later
let (slot, newValue) = k.cpt.stack.popInt(2)
checkInStaticContext(k.cpt)
# Minimum gas required to be present for an SSTORE call, not consumed
const SentryGasEIP2200 = 2300
if k.cpt.gasMeter.gasRemaining <= SentryGasEIP2200:
raise newException(OutOfGas, "Gas not enough to perform EIP2200 SSTORE")
when evmc_enabled:
if k.cpt.host.accessStorage(k.cpt.msg.contractAddress, slot) == EVMC_ACCESS_COLD:
k.cpt.gasMeter.consumeGas(ColdSloadCost, reason = "sstoreEIP2929")
else:
k.cpt.vmState.mutateStateDB:
if not db.inAccessList(k.cpt.msg.contractAddress, slot):
db.accessList(k.cpt.msg.contractAddress, slot)
k.cpt.gasMeter.consumeGas(ColdSloadCost, reason = "sstoreEIP2929")
when evmc_enabled:
sstoreEvmc(k.cpt, slot, newValue)
else:
sstoreNetGasMeteringImpl(k.cpt, slot, newValue)
# -------
jumpOp: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x56, Alter the program counter
let (jumpTarget) = k.cpt.stack.popInt(1)
jumpImpl(k.cpt, jumpTarget)
jumpIOp: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x57, Conditionally alter the program counter.
let (jumpTarget, testedValue) = k.cpt.stack.popInt(2)
if testedValue != 0:
jumpImpl(k.cpt, jumpTarget)
pcOp: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x58, Get the value of the program counter prior to the increment
## corresponding to this instruction.
k.cpt.stack.push:
max(k.cpt.code.pc - 1, 0)
msizeOp: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x59, Get the size of active memory in bytes.
k.cpt.stack.push:
k.cpt.memory.len
gasOp: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x5a, Get the amount of available gas, including the corresponding
## reduction for the cost of this instruction.
k.cpt.stack.push:
k.cpt.gasMeter.gasRemaining
jumpDestOp: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x5b, Mark a valid destination for jumps. This operation has no effect
## on machine state during execution.
discard
#[
EIP-2315: temporary disabled
Reason : not included in berlin hard fork
beginSubOp: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x5c, Marks the entry point to a subroutine
raise newException(
OutOfGas,
"Abort: Attempt to execute BeginSub opcode")
returnSubOp: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x5d, Returns control to the caller of a subroutine.
if k.cpt.returnStack.len == 0:
raise newException(
OutOfGas,
"Abort: invalid returnStack during ReturnSub")
k.cpt.code.pc = k.cpt.returnStack.pop()
jumpSubOp: Vm2OpFn = proc (k: var Vm2Ctx) =
## 0x5e, Transfers control to a subroutine.
let (jumpTarget) = k.cpt.stack.popInt(1)
if jumpTarget >= k.cpt.code.len.u256:
raise newException(
InvalidJumpDestination, "JumpSub destination exceeds code len")
let returnPC = k.cpt.code.pc
let jt = jumpTarget.truncate(int)
k.cpt.code.pc = jt
let nextOpcode = k.cpt.code.peek
if nextOpcode != BeginSub:
raise newException(
InvalidJumpDestination, "Invalid JumpSub destination")
if k.cpt.returnStack.len == 1023:
raise newException(
FullStack, "Out of returnStack")
k.cpt.returnStack.add returnPC
inc k.cpt.code.pc
]#
# ------------------------------------------------------------------------------
# Public, op exec table entries
# ------------------------------------------------------------------------------
const
vm2OpExecMemory*: seq[Vm2OpExec] = @[
(opCode: Pop, ## x50, Remove item from stack
forks: Vm2OpAllForks,
name: "pop",
info: "Remove item from stack",
exec: (prep: vm2OpIgnore,
run: popOp,
post: vm2OpIgnore)),
(opCode: Mload, ## 0x51, Load word from memory
forks: Vm2OpAllForks,
name: "mload",
info: "Load word from memory",
exec: (prep: vm2OpIgnore,
run: mloadOp,
post: vm2OpIgnore)),
(opCode: Mstore, ## 0x52, Save word to memory
forks: Vm2OpAllForks,
name: "mstore",
info: "Save word to memory",
exec: (prep: vm2OpIgnore,
run: mstoreOp,
post: vm2OpIgnore)),
(opCode: Mstore8, ## 0x53, Save byte to memory
forks: Vm2OpAllForks,
name: "mstore8",
info: "Save byte to memory",
exec: (prep: vm2OpIgnore,
run: mstore8Op,
post: vm2OpIgnore)),
(opCode: Sload, ## 0x54, Load word from storage
forks: Vm2OpAllForks - Vm2OpBerlinAndLater,
name: "sload",
info: "Load word from storage",
exec: (prep: vm2OpIgnore,
run: sloadOp,
post: vm2OpIgnore)),
(opCode: Sload, ## 0x54, sload for Berlin and later
forks: Vm2OpBerlinAndLater,
name: "sloadEIP2929",
info: "EIP2929: sload for Berlin and later",
exec: (prep: vm2OpIgnore,
run: sloadEIP2929Op,
post: vm2OpIgnore)),
(opCode: Sstore, ## 0x55, Save word
forks: Vm2OpAllForks - Vm2OpConstantinopleAndLater,
name: "sstore",
info: "Save word to storage",
exec: (prep: vm2OpIgnore,
run: sstoreOp,
post: vm2OpIgnore)),
(opCode: Sstore, ## 0x55, sstore for Constantinople and later
forks: Vm2OpConstantinopleAndLater - Vm2OpPetersburgAndLater,
name: "sstoreEIP1283",
info: "EIP1283: sstore for Constantinople and later",
exec: (prep: vm2OpIgnore,
run: sstoreEIP1283Op,
post: vm2OpIgnore)),
(opCode: Sstore, ## 0x55, sstore for Petersburg and later
forks: Vm2OpPetersburgAndLater - Vm2OpIstanbulAndLater,
name: "sstore",
info: "sstore for Constantinople and later",
exec: (prep: vm2OpIgnore,
run: sstoreOp,
post: vm2OpIgnore)),
(opCode: Sstore, ## 0x55, sstore for Istanbul and later
forks: Vm2OpIstanbulAndLater - Vm2OpBerlinAndLater,
name: "sstoreEIP2200",
info: "EIP2200: sstore for Istanbul and later",
exec: (prep: vm2OpIgnore,
run: sstoreEIP2200Op,
post: vm2OpIgnore)),
(opCode: Sstore, ## 0x55, sstore for Berlin and later
forks: Vm2OpBerlinAndLater,
name: "sstoreEIP2929",
info: "EIP2929: sstore for Istanbul and later",
exec: (prep: vm2OpIgnore,
run: sstoreEIP2929Op,
post: vm2OpIgnore)),
(opCode: Jump, ## 0x56, Jump
forks: Vm2OpAllForks,
name: "jump",
info: "Alter the program counter",
exec: (prep: vm2OpIgnore,
run: jumpOp,
post: vm2OpIgnore)),
(opCode: JumpI, ## 0x57, Conditional jump
forks: Vm2OpAllForks,
name: "jumpI",
info: "Conditionally alter the program counter",
exec: (prep: vm2OpIgnore,
run: jumpIOp,
post: vm2OpIgnore)),
(opCode: Pc, ## 0x58, Program counter prior to instruction
forks: Vm2OpAllForks,
name: "pc",
info: "Get the value of the program counter prior to the increment "&
"corresponding to this instruction",
exec: (prep: vm2OpIgnore,
run: pcOp,
post: vm2OpIgnore)),
(opCode: Msize, ## 0x59, Memory size
forks: Vm2OpAllForks,
name: "msize",
info: "Get the size of active memory in bytes",
exec: (prep: vm2OpIgnore,
run: msizeOp,
post: vm2OpIgnore)),
(opCode: Gas, ## 0x5a, Get available gas
forks: Vm2OpAllForks,
name: "gas",
info: "Get the amount of available gas, including the corresponding "&
"reduction for the cost of this instruction",
exec: (prep: vm2OpIgnore,
run: gasOp,
post: vm2OpIgnore)),
(opCode: JumpDest, ## 0x5b, Mark jump target. This operation has no effect
## on machine state during execution
forks: Vm2OpAllForks,
name: "jumpDest",
info: "Mark a valid destination for jumps",
exec: (prep: vm2OpIgnore,
run: jumpDestOp,
post: vm2OpIgnore))]
#[
EIP-2315: temporary disabled
Reason : not included in berlin hard fork
(opCode: BeginSub, ## 0x5c, Begin subroutine
forks: Vm2OpBerlinAndLater,
name: "beginSub",
info: " Marks the entry point to a subroutine",
exec: (prep: vm2OpIgnore,
run: beginSubOp,
post: vm2OpIgnore)),
(opCode: ReturnSub, ## 0x5d, Return
forks: Vm2OpBerlinAndLater,
name: "returnSub",
info: "Returns control to the caller of a subroutine",
exec: (prep: vm2OpIgnore,
run: returnSubOp,
post: vm2OpIgnore)),
(opCode: JumpSub, ## 0x5e, Call subroutine
forks: Vm2OpBerlinAndLater,
name: "jumpSub",
info: "Transfers control to a subroutine",
exec: (prep: vm2OpIgnore,
run: jumpSubOp,
post: vm2OpIgnore))]
]#
# ------------------------------------------------------------------------------
# End
# ------------------------------------------------------------------------------