Module ir_cache 

Thread-safe IR cache for compiled function arities.

Each CljxFnArity is assigned a unique ir_arity_id at creation time. When a function is called, the cache is consulted:

• NotAttempted → try lowering via the Clojure compiler
• Cached(ir) → execute via IR interpreter
• Unsupported → fall back to tree-walking (don’t retry)

The hot path (get_cached) uses RwLock so concurrent reads don’t contend. Writes (store) are infrequent (only during lowering).

Enums

IrCacheEntry

State of an IR cache entry for one function arity.

Functions

get_cached

Look up a cached IR function by arity ID. Returns None if not cached or if lowering previously failed. Returns Some(ir) if cached.

should_attempt

Check if lowering should be attempted for this arity. Returns true if the entry is NotAttempted (or absent).

store_cached

Store a successful IR compilation result.

store_unsupported

Mark an arity as unsupported (lowering failed; don’t retry).