Interface Coverage

hail-fuzz/src/coverage.rs:12–36

Keeps track of the global coverage seen across the input corpus.

/// Keeps track of the global coverage seen across the input corpus.
pub trait Coverage {
    /// Get a estimate of the global coverage.
    fn count(&self) -> u64;

    /// Return a reference to the bits in the coverage map.
    fn get_bits<'a>(&self, vm: &'a mut Vm) -> &'a [u64];

    /// Return the the index of any newly hit bits in the current coverage map.
    fn new_bits(&mut self, vm: &mut Vm) -> Vec<u32>;

    /// Merge the local coverage state with the global state, returning true if coverage increased.
    fn merge(&mut self, vm: &mut Vm) -> bool;

    fn serialize(&self, _vm: &mut Vm, _out: &mut String) {}

    /// Called at the very start of execution. Note: typically `restore_local` is used for
    /// resetting testcases between testcase executions.
    fn reset(&mut self, vm: &mut Vm);

    /// Create a snapshot of the (local) coverage state that can be later restored.
    fn snapshot_local(&mut self, vm: &mut Vm) -> Box<dyn Any>;

    /// Restore the (local) coverage state to a previously saved snapshot.
    fn restore_local(&mut self, vm: &mut Vm, snapshot: &Box<dyn Any>);
}

pub trait CoverageAny: Coverage {
    fn as_any(&self) -> &dyn std::any::Any;