nimbus-eth1/nimbus/vm/interpreter/utils/macros_procs_opcodes.nim

149 lines
4.9 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.
# ##################################################################
# Macros to facilitate opcode procs creation
import
macros, strformat, stint, eth/common,
vm/[computation, stack, code_stream, memory],
vm/types, errors, vm/interpreter/[gas_meter, opcode_values],
vm/interpreter/utils/utils_numeric
when defined(evmc_enabled):
import vm/evmc_api, evmc/evmc
proc pop(tree: var NimNode): NimNode =
## Returns the last value of a NimNode and remove it
result = tree[tree.len-1]
tree.del(tree.len-1)
macro op*(procname: untyped, inline: static[bool], stackParams_body: varargs[untyped]): untyped =
## Usage:
## .. code-block:: nim
## op add, inline = true, lhs, rhs:
## push:
## lhs + rhs
# TODO: Unfortunately due to varargs[untyped] consuming all following parameters,
# we can't have a nicer macro signature `stackParams: varargs[untyped], body: untyped`
# see https://github.com/nim-lang/Nim/issues/5855 and are forced to "pop"
let computation = newIdentNode("c")
var stackParams = stackParams_body
# 1. Separate stackParams and body with pop
let body = newStmtList().add stackParams.pop
# 3. let (x, y, z) = computation.stack.popInt(3)
let len = stackParams.len
var popStackStmt = nnkVarTuple.newTree()
if len != 0:
for params in stackParams:
popStackStmt.add newIdentNode(params.strVal)
popStackStmt.add newEmptyNode()
popStackStmt.add quote do:
`computation`.stack.popInt(`len`)
popStackStmt = nnkStmtList.newTree(
nnkLetSection.newTree(popStackStmt)
)
else:
popStackStmt = nnkDiscardStmt.newTree(newEmptyNode())
# 4. Generate the proc
# TODO: replace by func to ensure no side effects
if inline:
result = quote do:
proc `procname`*(`computation`: Computation) {.inline.} =
`popStackStmt`
`body`
else:
result = quote do:
proc `procname`*(`computation`: Computation) {.gcsafe.} =
`popStackStmt`
`body`
macro genPush*(): untyped =
# TODO: avoid allocating a seq[byte], transforming to a string, stripping char
func genName(size: int): NimNode = ident(&"push{size}")
result = newStmtList()
for size in 1 .. 32:
let name = genName(size)
result.add quote do:
func `name`*(computation: Computation) {.inline.}=
## Push `size`-byte(s) on the stack
computation.stack.push computation.code.readVmWord(`size`)
macro genDup*(): untyped =
func genName(position: int): NimNode = ident(&"dup{position}")
result = newStmtList()
for pos in 1 .. 16:
let name = genName(pos)
result.add quote do:
func `name`*(computation: Computation) {.inline.}=
computation.stack.dup(`pos`)
macro genSwap*(): untyped =
func genName(position: int): NimNode = ident(&"swap{position}")
result = newStmtList()
for pos in 1 .. 16:
let name = genName(pos)
result.add quote do:
func `name`*(computation: Computation) {.inline.}=
computation.stack.swap(`pos`)
template checkInStaticContext*(comp: Computation) =
# TODO: if possible, this check only appear
# when fork >= FkByzantium
if emvcStatic == comp.msg.flags:
raise newException(StaticContextError, "Cannot modify state while inside of a STATICCALL context")
proc logImpl(c: Computation, opcode: Op, topicCount: int) =
doAssert(topicCount in 0 .. 4)
checkInStaticContext(c)
let (memStartPosition, size) = c.stack.popInt(2)
let (memPos, len) = (memStartPosition.cleanMemRef, size.cleanMemRef)
if memPos < 0 or len < 0:
raise newException(OutOfBoundsRead, "Out of bounds memory access")
c.gasMeter.consumeGas(
c.gasCosts[opcode].m_handler(c.memory.len, memPos, len),
reason="Memory expansion, Log topic and data gas cost")
c.memory.extend(memPos, len)
when evmc_enabled:
var topics: array[4, evmc_bytes32]
for i in 0 ..< topicCount:
topics[i].bytes = c.stack.popTopic()
c.host.emitLog(c.msg.contractAddress,
c.memory.read(memPos, len),
topics[0].addr, topicCount)
else:
var log: Log
log.topics = newSeqOfCap[Topic](topicCount)
for i in 0 ..< topicCount:
log.topics.add(c.stack.popTopic())
log.data = c.memory.read(memPos, len)
log.address = c.msg.contractAddress
c.addLogEntry(log)
template genLog*() =
proc log0*(c: Computation) {.inline.} = logImpl(c, Log0, 0)
proc log1*(c: Computation) {.inline.} = logImpl(c, Log1, 1)
proc log2*(c: Computation) {.inline.} = logImpl(c, Log2, 2)
proc log3*(c: Computation) {.inline.} = logImpl(c, Log3, 3)
proc log4*(c: Computation) {.inline.} = logImpl(c, Log4, 4)