nimbus-eth1/nimbus/evm/interpreter/op_dispatcher.nim

174 lines
5.6 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.
const
# debugging flag, dump macro info when asked for
noisy {.intdefine.}: int = 0
# isNoisy {.used.} = noisy > 0
isChatty {.used.} = noisy > 1
import
../code_stream,
../computation,
../../common/evmforks,
./gas_costs,
./gas_meter,
./op_codes,
./op_handlers,
./op_handlers/oph_defs,
chronicles,
macros
export
EVMFork, Op,
oph_defs,
gas_meter
# ------------------------------------------------------------------------------
# Helpers
# ------------------------------------------------------------------------------
template handleStopDirective(k: var Vm2Ctx) =
#trace "op: Stop"
if not k.cpt.code.atEnd() and k.cpt.tracingEnabled:
# we only trace `REAL STOP` and ignore `FAKE STOP`
k.cpt.opIndex = k.cpt.traceOpCodeStarted(Stop)
k.cpt.traceOpCodeEnded(Stop, k.cpt.opIndex)
template handleFixedGasCostsDirective(fork: EVMFork; op: Op; k: var Vm2Ctx) =
if k.cpt.tracingEnabled:
k.cpt.opIndex = k.cpt.traceOpCodeStarted(op)
k.cpt.opcodeGastCost(op, k.cpt.gasCosts[op].cost, reason = $op)
vmOpHandlers[fork][op].run(k)
# If continuation is not nil, traceOpCodeEnded will be called in executeOpcodes.
if k.cpt.tracingEnabled and k.cpt.continuation.isNil:
k.cpt.traceOpCodeEnded(op, k.cpt.opIndex)
template handleOtherDirective(fork: EVMFork; op: Op; k: var Vm2Ctx) =
if k.cpt.tracingEnabled:
k.cpt.opIndex = k.cpt.traceOpCodeStarted(op)
vmOpHandlers[fork][op].run(k)
# If continuation is not nil, traceOpCodeEnded will be called in executeOpcodes.
if k.cpt.tracingEnabled and k.cpt.continuation.isNil:
k.cpt.traceOpCodeEnded(op, k.cpt.opIndex)
# ------------------------------------------------------------------------------
# Private, big nasty doubly nested case matrix generator
# ------------------------------------------------------------------------------
# reminiscent of Mamy's opTableToCaseStmt() from original VM
proc toCaseStmt(forkArg, opArg, k: NimNode): NimNode =
# Outer case/switch => Op
let branchOnOp = quote do: `opArg`
result = nnkCaseStmt.newTree(branchOnOp)
for op in Op:
let asOp = quote do: Op(`op`)
# Inner case/switch => Fork
let branchOnFork = quote do: `forkArg`
var forkCaseSubExpr = nnkCaseStmt.newTree(branchOnFork)
for fork in EVMFork:
let asFork = quote do: EVMFork(`fork`)
let gcTable = forkToGck[fork]
let branchStmt = block:
if op == Stop:
quote do:
handleStopDirective(`k`)
elif gcTable[op] == GckFixed:
quote do:
handleFixedGasCostsDirective(`asFork`,`asOp`,`k`)
else:
quote do:
handleOtherDirective(`asFork`,`asOp`,`k`)
forkCaseSubExpr.add nnkOfBranch.newTree(asFork, branchStmt)
# Wrap innner case/switch into outer case/switch
let branchStmt = block:
case op
of Stop, Return, Revert, SelfDestruct:
quote do:
`forkCaseSubExpr`
break
else:
# FIXME-manyOpcodesNowRequireContinuations
# We used to have another clause in this case statement for various
# opcodes that *don't* need to check for a continuation. But now
# there are many opcodes that need to, because they call asyncChainTo
# (and so they set a pendingAsyncOperation and a continuation that
# needs to be noticed by the interpreter_dispatch loop). And that
# will become even more true once we implement speculative execution,
# because that will mean that even reading from the stack might
# require waiting.
#
# Anyway, the point is that now we might as well just do this check
# for *every* opcode (other than Return/Revert/etc, which need to
# break no matter what).
quote do:
`forkCaseSubExpr`
if not `k`.cpt.continuation.isNil:
break
result.add nnkOfBranch.newTree(asOp, branchStmt)
when isChatty:
echo ">>> ", result.repr
# ------------------------------------------------------------------------------
# Public macros/functions
# ------------------------------------------------------------------------------
macro genOptimisedDispatcher*(fork: EVMFork; op: Op; k: Vm2Ctx): untyped =
result = fork.toCaseStmt(op, k)
template genLowMemDispatcher*(fork: EVMFork; op: Op; k: Vm2Ctx) =
if op == Stop:
handleStopDirective(k)
break
if BaseGasCosts[op].kind == GckFixed:
handleFixedGasCostsDirective(fork, op, k)
else:
handleOtherDirective(fork, op, k)
case c.instr
of Return, Revert, SelfDestruct:
break
else:
# FIXME-manyOpcodesNowRequireContinuations
if not k.cpt.continuation.isNil:
break
# ------------------------------------------------------------------------------
# Debugging ...
# ------------------------------------------------------------------------------
when isMainModule and isChatty:
import ../types
proc optimised(c: Computation, fork: EVMFork) {.compileTime.} =
var desc: Vm2Ctx
while true:
genOptimisedDispatcher(fork, desc.cpt.instr, desc)
# ------------------------------------------------------------------------------
# End
# ------------------------------------------------------------------------------