use crate::{
evm_circuit::{
execution::ExecutionGadget,
step::ExecutionState,
util::{
common_gadget::SameContextGadget,
constraint_builder::{EVMConstraintBuilder, StepStateTransition, Transition::Delta},
CachedRegion,
},
witness::{Block, Call, Chunk, ExecStep, Transaction},
},
util::Expr,
};
use bus_mapping::evm::OpcodeId;
use eth_types::Field;
use halo2_proofs::plonk::Error;
#[derive(Clone, Debug)]
pub(crate) struct JumpdestGadget<F> {
same_context: SameContextGadget<F>,
}
impl<F: Field> ExecutionGadget<F> for JumpdestGadget<F> {
const NAME: &'static str = "JUMPDEST";
const EXECUTION_STATE: ExecutionState = ExecutionState::JUMPDEST;
fn configure(cb: &mut EVMConstraintBuilder<F>) -> Self {
let step_state_transition = StepStateTransition {
program_counter: Delta(1.expr()),
gas_left: Delta(-OpcodeId::JUMPDEST.constant_gas_cost().expr()),
..Default::default()
};
let opcode = cb.query_cell();
let same_context = SameContextGadget::construct(cb, opcode, step_state_transition);
Self { same_context }
}
fn assign_exec_step(
&self,
region: &mut CachedRegion<'_, '_, F>,
offset: usize,
_: &Block<F>,
_: &Chunk<F>,
_: &Transaction,
_: &Call,
step: &ExecStep,
) -> Result<(), Error> {
self.same_context.assign_exec_step(region, offset, step)
}
}
#[cfg(test)]
mod test {
use crate::test_util::CircuitTestBuilder;
use eth_types::bytecode;
use mock::TestContext;
#[test]
fn jumpdest_gadget_simple() {
let bytecode = bytecode! {
JUMPDEST
STOP
};
CircuitTestBuilder::new_from_test_ctx(
TestContext::<2, 1>::simple_ctx_with_bytecode(bytecode).unwrap(),
)
.run();
}
}