JIT benchmarks

Measured on macOS ARM64 (M3), in v0.7.1.

Compile time

Benchmark	Cold (binary)	Warm (cached)	Daemon
`add(40,2)`	~35 ms	~0.1 ms	~0.3 ms
`fib(30)`	~35 ms	~0.1 ms	~0.3 ms
Polyglot sample (38 files)	~1.9 s	~0.5 s	~0.5 s

Cold times are dominated by the in binary's process startup (~30 ms). The actual parse + lower + emit for small workloads is under 2 ms. in daemon start removes that startup cost for repeated eval/build calls.

Execution time

Benchmark	JIT (native)
`fib(30)`	~1 ms
`fib(35)`	~55 ms

The JIT path emits AArch64 machine code and is the default execution path.

Status

Op	JIT
IntLit, FloatLit, BoolLit, StringLit	✅
Ident, Binary, Unary	✅
Call, Return, If/Else, While, Let, Assign	✅
Match	✅
Struct, Array	✅ (native subset)
Closure	❌

Architecture

Source → parser → Core IR → native_emit/lower → AArch64/x86_64 machine code
                                                    ↓
                                              mmap(MAP_JIT) / boot image

No LLVM, no external linker on the JIT path
No bytecode VM; JIT is the only execution path
x86_64 lowering is used for freestanding boot images
I-cache flushed via sys_icache_invalidate on Apple Silicon

Optimization opportunities

Native lowering — cache lowered function bodies when the source hash and target triple haven't changed.
Incremental parse — reuse the Core IR cache for unchanged imports.
Function-level parallel lowering — lower independent functions in parallel.