Struct wasm_instrument::gas_metering::ConstantCostRules

pub struct ConstantCostRules { /* private fields */ }

A type that implements Rules so that every instruction costs the same.

This is a simplification that is mostly useful for development and testing.

Note

In a production environment it usually makes no sense to assign every instruction the same cost. A proper implemention of Rules should be provided that is probably created by benchmarking.

Implementations

impl ConstantCostRules

pub fn new(
    instruction_cost: u32,
    memory_grow_cost: u32,
    call_per_local_cost: u32
) -> Self

Create a new ConstantCostRules.

Uses instruction_cost for every instruction and memory_grow_cost to dynamically meter the memory growth instruction.

Trait Implementations

impl Default for ConstantCostRules

fn default() -> Self

Uses instruction cost of 1 and disables memory growth instrumentation.

impl Rules for ConstantCostRules

fn instruction_cost(&self, _: &Instruction) -> Option<u32>

Returns the cost for the passed instruction.

fn memory_grow_cost(&self) -> MemoryGrowCost

Returns the costs for growing the memory using the memory.grow instruction.

fn call_per_local_cost(&self) -> u32

A surcharge cost to calling a function that is added per local of that function.