Struct Stats 

pub struct Stats {

    pub opcodes: u64,
    pub steps: u64,
    pub threads_created: u64,
    pub threads_completed: u64,
    pub frames_pushed: u64,
    pub frames_popped: u64,
    pub choices_presented: u64,
    pub choices_selected: u64,
    pub snapshot_cache_hits: u64,
    pub snapshot_cache_misses: u64,
    pub materializations: u64,
    pub opcode_hist: Vec<u64>,
    pub bigram_hist: Vec<u64>,
    pub last_disc: Option<u8>,
}

Lightweight counters tracking VM activity over a story’s lifetime.

Always-on — incrementing a u64 is effectively free compared to opcode dispatch. Use [Story::stats] to read after a run.

Fields

opcodes: u64

Total opcodes dispatched.

steps: u64

Total vm::step calls from the outer loop.

threads_created: u64

Threads forked (via ThreadCall and choice creation).

threads_completed: u64

Threads that completed and were popped.

frames_pushed: u64

Call frames pushed onto thread stacks.

frames_popped: u64

Call frames popped from thread stacks.

choices_presented: u64

Choice sets presented to the player.

choices_selected: u64

Individual choices selected.

snapshot_cache_hits: u64

CallStack::snapshot cache hits (reused existing Arc).

snapshot_cache_misses: u64

CallStack::snapshot cache misses (new allocation).

materializations: u64

CallStack::materialize calls (flattened inherited prefix).

opcode_hist: Vec<u64>

Executed-instruction histogram by discriminant byte (256 entries, sized on first use). Bench instrumentation only: the optimizer’s peephole work needs to know which instructions — and which pairs — actually run, not which exist in the artifact.

bigram_hist: Vec<u64>

Executed instruction-pair histogram, indexed prev << 8 | next (65 536 entries, sized on first use).

last_disc: Option<u8>

The previously executed discriminant, for bigram_hist.

Trait Implementations

impl Clone for Stats

fn clone(&self) -> Stats

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Stats

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Stats

fn default() -> Stats

Returns the “default value” for a type.