XCX 2.2: Performance & Efficiency

CORE PERFORMANCE

JIT Compilation — Cranelift-based JIT; 1B-iteration triple nested loop benchmark: ~478ms vs ~140s in 2.1 (~293x speedup).

Trace Recording — Automatic trace capture and native code generation for loops.

NaN-Boxed Values — Optimized 64-bit value representation (8 bytes).

Lock-Free Atomics — Improved concurrency with AtomicBool shutdown handling.

VM IMPROVEMENTS

Optimized Opcodes — New IncLocalLoopNext, IncVarLoopNext, GuardInt/Float for faster execution.

Better Fiber Support — Enhanced FiberState with yield value caching.

MIGRATION NOTES

Feature 2.1 2.2

Execution Interpreted JIT + Interpreted

Value Size 24+ bytes 8 bytes

Loop Perf (1B) ~140s ~478ms

IMPORTANT: Bytecode is not compatible with 2.1. Requires cranelift, parking_lot, and argon2.